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1

GREEN LIVING Replace incandencent and halogen light bulbs with LED and CLFs  

E-Print Network (OSTI)

GREEN LIVING GUIDE ENERGY TRAVEL FOOD sustain yosef WATER Replace incandencent and halogen light POWER STRIPS! for you electronics, and turn them off when not in use Adjust your thermostat UP IN SUMMER Bicycle Initiative http://boonebikeinitiative.org LEAVE YOUR CAR AT HOME - save $ on a parking pass

Thaxton, Christopher S.

2

The European Commission's light bulb decree: Another costly regulation?  

Science Journals Connector (OSTI)

Since September 2009, Regulation 244/2009 of the European Commission enforces the gradual phase-out of incandescent light bulbs. As of September 2012, only energy-efficient lighting sources will be allowed for sale. Among these are halogen light bulbs, light-emitting diodes (LED), or compact fluorescent light bulbs—often referred to as energy-saving light bulbs. The Commission's justification for the phase-out of conventional light bulbs maintains that a reduction in the electricity consumed will not only lead to lower energy cost for private households and industrial consumers, but at the same time lead to a decrease in greenhouse gas emissions. This article discusses possible reasons for the slow market diffusion of energy-saving light bulbs and shows that the investment in energy-efficient light bulbs does not necessarily lead to significant cost reductions. Drawing on some illustrative examples, we demonstrate that the use of cheaper incandescent bulbs instead of energy-saving light bulbs can be economically rational in cases of rather low usage times, in which the higher initial purchasing price might only pay off after very long time spans. Furthermore, due to the coexistence with the European Emissions Trading Scheme (ETS), this regulation attains no additional emission reductions beyond those achieved by the ETS alone. We thus conclude that the general ban of incandescent light bulbs is inappropriate and should be abolished by the Commission.

Manuel Frondel; Steffen Lohmann

2011-01-01T23:59:59.000Z

3

Type II halogen???halogen contacts are halogen bonds  

Science Journals Connector (OSTI)

Cl/Br/I alternative substitutions in a series of dihalophenols indicate that type I and type II halogen???halogen contacts have different chemical nature. Only the latter ones qualify as true halogen bonds, according to the recent IUPAC definition.

Metrangolo, P.

2013-12-31T23:59:59.000Z

4

Comparing Light Bulbs  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Comparing Light Bulbs Grades: K-4, 5-8 Topic: Energy Efficiency and Conservation Owner: U.S. Environmental Protection Agency This educational material is brought to you by the U.S....

5

Information Resources: L Prize(tm): The Race for Super Efficient Light Bulbs  

NLE Websites -- All DOE Office Websites (Extended Search)

L Prize(tm): The Race for Super Efficient Light Bulbs L Prize(tm): The Race for Super Efficient Light Bulbs This September 23, 2008 webcast provided an overview of the Bright Tomorrow Lighting Prize (L Prize) technology competition. The L Prize calls for super-efficient SSL products to replace two of the most common light bulbs used today: the 60-watt incandescent and the PAR-38 halogen reflector. Kelly Gordon, Pacific Northwest National Laboratory, kicked off the webcast with an overview of the competition requirements, evaluation process, and opportunities for promotion of the winning products. Mary Matteson Bryan, Pacific Gas & Electric, and Liesel Whitney-Schulte, Wisconsin Focus on Energy, followed with a look at the role of L Prize partners and plans for their organizations to support the winning products through demonstrations, education, promotions, and other collaborative efforts.

6

Halogenation of cobalt dicarbollide  

DOE Patents (OSTI)

A method for selectively adding chlorine, bromine, or iodine to cobalt dicarbollide anions by means of electrophilic substitution reactions. Halogens are added only to the B10 and B10{prime} positions of the anion. The process involves use of hypohalous acid or N-halosuccinimide or gaseous chlorine in the presence of iron. 1 fig.

Hurlburt, P.K.; Abney, K.D.; Kinkead, S.A.

1997-05-20T23:59:59.000Z

7

How Energy-Efficient Light Bulbs Compare with Traditional Incandescent...  

NLE Websites -- All DOE Office Websites (Extended Search)

How Energy-Efficient Light Bulbs Compare with Traditional Incandescents How Energy-Efficient Light Bulbs Compare with Traditional Incandescents July 28, 2014 - 11:39pm Addthis...

8

Fusion Reaction of Halo Nuclei: Proton Halo versus Neutron Halo  

Science Journals Connector (OSTI)

......February 2004 research-article Articles Fusion Reaction of Halo Nuclei: Proton Halo...Tsukuba, Tsukuba 305-8571, Japan. The fusion reaction of halo nuclei on heavy target...Schrodinger equation. We find that the fusion probability is enhanced by the presence......

Takashi Nakatsukasa; Kazuhiro Yabana; Makoto Ito; Minoru Kobayashi; Manabu Ueda

2004-02-01T23:59:59.000Z

9

The History of the Light Bulb | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

The History of the Light Bulb The History of the Light Bulb The History of the Light Bulb November 22, 2013 - 1:00pm Addthis History of the Light Bulb Rebecca Matulka Rebecca Matulka Digital Communications Specialist, Office of Public Affairs Daniel Wood Daniel Wood Data Integration Specialist What are the key facts? Like all great inventions, the light bulb can't be credited to one inventor. It was a series of small improvements on the ideas of previous inventors that have led to the light bulbs we use in our homes today. Learn more about the history of the incandescent light bulb. Explore the history of fluorescent lights, from the Geissler tube to CFLs. Read about the advancements in LED lights. More than 150 years ago, inventors began working on a bright idea that would have a dramatic impact on how we use energy in our homes and offices.

10

How Energy-Efficient Light Bulbs Compare with Traditional Incandescents |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Energy-Efficient Light Bulbs Compare with Traditional Energy-Efficient Light Bulbs Compare with Traditional Incandescents How Energy-Efficient Light Bulbs Compare with Traditional Incandescents July 29, 2012 - 6:25pm Addthis Energy-efficient light bulbs are available today and could save you about $50 per year in energy costs when you replace 15 traditional incandescent bulbs in your home. Energy-efficient light bulbs are available today and could save you about $50 per year in energy costs when you replace 15 traditional incandescent bulbs in your home. Compared to traditional incandescents, energy-efficient lightbulbs such as energy-saving incandescents, compact fluorescent lamps (CFLs), and light emitting diodes (LEDs) have the following advantages: Typically use about 25%-80% less energy, saving you money

11

The History of the Light Bulb | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

The History of the Light Bulb The History of the Light Bulb The History of the Light Bulb November 22, 2013 - 1:00pm Addthis History of the Light Bulb Rebecca Matulka Rebecca Matulka Digital Communications Specialist, Office of Public Affairs Daniel Wood Daniel Wood Data Integration Specialist What are the key facts? Like all great inventions, the light bulb can't be credited to one inventor. It was a series of small improvements on the ideas of previous inventors that have led to the light bulbs we use in our homes today. Learn more about the history of the incandescent light bulb. Explore the history of fluorescent lights, from the Geissler tube to CFLs. Read about the advancements in LED lights. More than 150 years ago, inventors began working on a bright idea that would have a dramatic impact on how we use energy in our homes and offices.

12

E-Print Network 3.0 - active halogen species Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

organo-halogen gases or solvents. The most abundant... Zevenhoven & Kilpinen Halogens, dioxinsfurans 17.6.2001 7-1 Chapter 7 Halogens, dioxinsfurans 7... .1 Introduction The...

13

FIELD SCREENING FOR HALOGENATED VOLATILE ORGANIC COMPOUNDS  

SciTech Connect

Western Research Institute (WRI) initiated exploratory work towards the development of new field screening methodology and a test kit to measure halogenated volatile organic compounds (VOCs) in the field. Heated diode and corona discharge sensors are commonly used to detect leaks of refrigerants from air conditioners, freezers, and refrigerators. They are both selective to the presence of carbon-halogen bonds. Commercially available heated diode and corona discharge leak detectors were procured and evaluated for halogenated VOC response. The units were modified to provide a digital readout of signal related to VOC concentration. Sensor response was evaluated with carbon tetrachloride and tetrachloroethylene (perchloroethylene, PCE), which represent halogenated VOCs with and without double bonds. The response characteristics were determined for the VOCs directly in headspace in Tedlar bag containers. Quantitation limits in air were estimated. Potential interferences from volatile hydrocarbons, such as toluene and heptane, were evaluated. The effect of humidity was studied also. The performance of the new devices was evaluated in the laboratory by spiking soil samples and monitoring headspace for halogenated VOCs. A draft concept of the steps for a new analytical method was outlined. The results of the first year effort show that both devices show potential utility for future analytical method development work towards the goal of developing a portable test kit for screening halogenated VOCs in the field.

John F. Schabron; Joseph F. Rovani Jr.; Theresa M. Bomstad

2002-06-01T23:59:59.000Z

14

Which Bulb Is Right for You? (High-Resolution JPG Billboard)...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

More Documents & Publications Which Bulb Is Right for You? (High-Resolution EPS Billboard) Which Bulb Is Right for You? (Low-Resolution JPG Billboard) Goodbye, Watts....

15

Crystallographic studies on enzymatic halogenation of natural products  

E-Print Network (OSTI)

Halogenated natural products are common and serve roles as hormones, pesticides, antibiotics, and anti-tumor agents. The incorporation of a halogen atom into an organic scaffold can tune the molecule's potency and selectivity, ...

Blasiak, Leah Cameron

2008-01-01T23:59:59.000Z

16

Tokamak halo currents  

SciTech Connect

A halo current flows for part of its path through the plasma edge and for part through the chamber walls and can be as large as tenths of the plasma current. The primary interest in halo currents is the large force that they can exert on machine components. Two discordant constraints are central to the theory: (1) Halo currents must produce the magnetic field distribution required to maintain plasma force balance—a distribution that depends on the two angular coordinates of a torus. (2) Halo currents must flow along the magnetic field lines in the plasma, which implies a dependence on a linear combination of the two angular coordinates—only one angular coordinate is free. The physics basis of these two constraints is explained as is their application to the calculation of the properties of halo currents, such as their broad toroidal spectrum. Existing codes could be used to (1) provide detailed comparisons with experiments to validate that the critical elements of physics are adequately included, (2) allow more complete predictions for future machines such as ITER, and (3) design shunts and resistive elements to ensure halo currents follow paths that are the least damaging to the machine. The physics of halo currents implies that it may be possible to feedback stabilize resistive wall modes beyond the ideal-wall limit.

Boozer, Allen H. [Department of Applied Physics and Applied Mathematics Columbia University, New York, New York 10027 (United States)] [Department of Applied Physics and Applied Mathematics Columbia University, New York, New York 10027 (United States)

2013-08-15T23:59:59.000Z

17

A cheap simple ammeter for batteries-and-bulbs activities  

Science Journals Connector (OSTI)

The use of batteries and bulbs to teach the fundamentals of circuit analysis has been with us for many years. Even recent innovations in pedagogy seem to rely on batteries and bulbs. In addition the California Science Content Standards for fourth grade require that “students know how to design and build simple series and parallel circuits using components such as wires batteries and bulbs.” These standards go on to indicate that students should be able to use a compass to detect magnetic fields and know that electric currents produce magnetic fields.

David T. Kagan

2000-01-01T23:59:59.000Z

18

How Many CASTLE Bulbs Would You Need To Match the Brightness of the Sun?  

E-Print Network (OSTI)

;Suppose that you have two household incandescent bulbs: one is labeled "60W," the other "100W." If you try incandescent bulb and a 9W fluorescent bulb. Which one makes your room brighter? It's not what you might expect... in fact, they look about the same! The incandescent bulb emits a broad spectrum of visible and infrared

Collar, Juan I.

19

Zevenhoven & Kilpinen Halogens, dioxins/furans 17.6.2001 7-1 Chapter 7 Halogens,  

E-Print Network (OSTI)

Zevenhoven & Kilpinen Halogens, dioxins/furans 17.6.2001 7-1 Chapter 7 Halogens, dioxins/furans 7 in Figure 7.1. The polychlorinated dibenzo -(p) dioxins and -furans (PCDD/Fs) that are found in PCBs and may, dioxins/furans 17.6.2001 7-2 2,3,7,8 tetrachloro dibenzo - p- dioxin PCB furan 2,3,7,8 tetrachlorodibenzo

Zevenhoven, Ron

20

Changing How You Choose Light Bulbs | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Changing How You Choose Light Bulbs Changing How You Choose Light Bulbs Changing How You Choose Light Bulbs July 12, 2010 - 7:30am Addthis Elizabeth Spencer Communicator, National Renewable Energy Laboratory Last month, the Federal Trade Commission announced that light bulbs will have a brand new style of packaging, starting in 2011. This is super exciting news! Well, all right, maybe "exciting" is a bit of a stretch, but it's certainly useful if you're thinking in terms of saving money and energy. Which is, I hope, one of the reasons people come to this blog. Example of the Lighting Facts label. The new form is based on a simple idea: There's an absolute ton of different kinds of lighting out there, but for most lights, the only information on the package is the wattage-the amount of power it draws.

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Changing How You Choose Light Bulbs | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Changing How You Choose Light Bulbs Changing How You Choose Light Bulbs Changing How You Choose Light Bulbs July 12, 2010 - 7:30am Addthis Elizabeth Spencer Communicator, National Renewable Energy Laboratory Last month, the Federal Trade Commission announced that light bulbs will have a brand new style of packaging, starting in 2011. This is super exciting news! Well, all right, maybe "exciting" is a bit of a stretch, but it's certainly useful if you're thinking in terms of saving money and energy. Which is, I hope, one of the reasons people come to this blog. Example of the Lighting Facts label. The new form is based on a simple idea: There's an absolute ton of different kinds of lighting out there, but for most lights, the only information on the package is the wattage-the amount of power it draws.

22

Method and apparatus for detecting halogenated hydrocarbons  

DOE Patents (OSTI)

A halogenated hydrocarbon (HHC) detector is formed from a silent discharge (also called a dielectric barrier discharge) plasma generator. A silent discharge plasma device receives a gas sample that may contain one or more HHCs and produces free radicals and excited electrons for oxidizing the HHCs in the gas sample to produce water, carbon dioxide, and an acid including halogens in the HHCs. A detector is used to sensitively detect the presence of the acid. A conductivity cell detector combines the oxidation products with a solvent where dissociation of the acid increases the conductivity of the solvent. The conductivity cell output signal is then functionally related to the presence of HHCs in the gas sample. Other detectors include electrochemical cells, infrared spectrometers, and negative ion mobility spectrometers.

Monagle, Matthew (Los Alamos, NM); Coogan, John J. (Los Alamos, NM)

1997-01-01T23:59:59.000Z

23

Computational investigation of the SN2 reactivity of halogenated pollutants.  

E-Print Network (OSTI)

??The SN2 displacement reaction, in which a halide is displaced from a molecule by a nucleophile represents an important mechanism by which halogenated pollutants can… (more)

Stanford University, Dept. of Civil and Environmental; Engineering

2011-01-01T23:59:59.000Z

24

Solid-State Lighting: L Prize(tm): The Race for Super Efficient Light Bulbs  

NLE Websites -- All DOE Office Websites (Extended Search)

L Prize(tm): The Race for Super L Prize(tm): The Race for Super Efficient Light Bulbs to someone by E-mail Share Solid-State Lighting: L Prize(tm): The Race for Super Efficient Light Bulbs on Facebook Tweet about Solid-State Lighting: L Prize(tm): The Race for Super Efficient Light Bulbs on Twitter Bookmark Solid-State Lighting: L Prize(tm): The Race for Super Efficient Light Bulbs on Google Bookmark Solid-State Lighting: L Prize(tm): The Race for Super Efficient Light Bulbs on Delicious Rank Solid-State Lighting: L Prize(tm): The Race for Super Efficient Light Bulbs on Digg Find More places to share Solid-State Lighting: L Prize(tm): The Race for Super Efficient Light Bulbs on AddThis.com... Conferences & Meetings Presentations Publications Webcasts Videos Tools L Prize(tm): The Race for Super Efficient Light Bulbs

25

Which Bulb Is Right for You? (High-Resolution EPS Billboard)...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

EPS Billboard) Which Bulb Is Right for You? (High-Resolution EPS Billboard) High-resolution EPS of billboard reading, 'Which bulb is right for you? Save energy, save money....

26

E-Print Network 3.0 - anesthesiques halogenes pendant Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

Collection: Chemistry 38 HELSINKI UNIVERSITY OF TECHNOLOGY ENE-47.153 Halogens, dioxinsHalogens, dioxinsfuransfurans Summary: HELSINKI UNIVERSITY OF TECHNOLOGY ENE-47.153...

27

Text-Alternative Version: L Prize™: The Race for Super Efficient Light Bulbs  

Energy.gov (U.S. Department of Energy (DOE))

Below is the text-alternative version of the L Prize™: The Race for Super Efficient Light Bulbs webcast.

28

FIELD SCREENING FOR HALOGENATED VOLATILE ORGANIC COMPOUNDS  

SciTech Connect

Western Research Institute (WRI) is continuing work toward the development of new screening methodology and a test kit to measure halogenated volatile organic compounds (VOCs) in the field. Heated diode and corona discharge sensors are commonly used to detect leaks of refrigerants from air conditioners, freezers, and refrigerators. They are both selective to the presence of halogens. In prior work, the devices were tested for response to carbon tetrachloride, heptane, toluene, and water vapors. In the current work, sensor response was evaluated with sixteen halogenated VOCs relative to carbon tetrachloride. The results show that the response of the various chlorinated VOCs is within an order of magnitude of the response to carbon tetrachloride for each of the sensors. Thus, for field screening a single response factor can be used. Both types of leak detectors are being further modified to provide an on-board LCD signal readout, which is related to VOC concentration. The units will be fully portable and will operate with 115-V line or battery power. Signal background, noise level, and response data on the Bacharach heated diode detector and the TIF corona discharge detector show that when the response curves are plotted against the log of concentration, the plot is linear to the upper limit for the particular unit, with some curvature at lower levels. When response is plotted directly against concentration, the response is linear at the low end and is curved at the high end. The dynamic ranges for carbon tetrachloride of the two devices from the lower detection limit (S/N=2) to signal saturation are 4-850 vapor parts per million (vppm) for the corona discharge unit and 0.01-70 vppm for the heated diode unit. Additional circuit modifications are being made to lower the detection limit and increase the dynamic response range of the corona discharge unit. The results indicate that both devices show potential utility for future analytical method development work toward the goal of developing a portable test kit for screening halogenated VOCs in the field.

John F. Schabron; Joseph F. Rovani, Jr.; Theresa M. Bomstad

2003-07-01T23:59:59.000Z

29

Free Energy Efficiency Kit includes CFL light bulbs,  

E-Print Network (OSTI)

Free Energy Efficiency Kit Kit includes CFL light bulbs, spray foam, low-flow shower head, and more! Building Science 101 Presentation BPI Certified Building Professionals will present home energy efficiency for discounted energy assessments. FREE HOME ENERGY EFFICIENCY SEMINAR N e w R i ver L i g ht & Pow e r a n d W

Rose, Annkatrin

30

Krypton-filled light bulbs enter consumer market  

Science Journals Connector (OSTI)

Duro-Test Corp., North Bergen, N.J., this month began marketing a krypton-filled bulb and Westinghouse Electric will enter the market this fall. ... Its lower heat conductivity reduces energy loss from the filament, allowing the filament to run hotter and the glass jacket to run cooler. ...

1968-06-24T23:59:59.000Z

31

The “Green Lab”: Power Consumption by Commercial Light Bulbs  

Science Journals Connector (OSTI)

Going “green” is a slogan that is very contemporary both with industry and in the political arena. Choosing more energy-efficient devices is one way homeowners can “go green.” A simple method is to change home lighting from hot incandescent bulbs to compact fluorescent lights (CFLs). But do they really save energy? How do their illuminations compare? Even if the CFLs are more energy efficient they still add to our pollution problem because of the mercury inside them. Light-emitting diodes(LEDs) could be the answer but they are not available at our local stores. Can LEDs be made to screw right into a standard socket? How expensive are they? What are the power consumptions of so-called “60-W” and “100-W” CFL and LED light bulbs? These are the questions that are answered during this lab activity. Students measure the voltage and current for each of the three types of bulbs and then calculate the electrical power required by each. An optional experiment is to set the light outputs of each bulb so they are equal in intensity and then determine the power consumed. While not practical in the home this experiment gives students an understanding of value for their buck.

James A. Einsporn; Andrew F. Zhou

2011-01-01T23:59:59.000Z

32

A Bit About Bulbs Night temperatures are cool, the air is almost crisp. The vegetable harvest is tapering  

E-Print Network (OSTI)

work their way down and stems go up where they belong. Purchase from reliable dealers to assure quality is the general rule to follow. If you are dealing with a strangely shaped bulb species that doesn't seem to have of moisture. A quality bulb is a large bulb; it will produce larger flowers and more of them. The bulb should

New Hampshire, University of

33

Westinghouse and Fuzhou Permitted to Restart Distribution of Light Bulb  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Westinghouse and Fuzhou Permitted to Restart Distribution of Light Westinghouse and Fuzhou Permitted to Restart Distribution of Light Bulb Products Westinghouse and Fuzhou Permitted to Restart Distribution of Light Bulb Products August 6, 2010 - 4:26pm Addthis The Department has issued Notices of Allowance to Westinghouse Lighting Corporation and Fuzhou Sunlight Lighting Electrical Appliance Company determining, based on corrected test data provided by Westinghouse, that the incandescent reflector lamps listed below are compliant with the federal energy conservation standard and may be sold in the United States. These 11 Westinghouse brand lamps, usually used in recessed light fixtures, correspond to 7 basic models, which are manufactured in China by Fuzhou. DOE had previously issued Notices requiring Fuzhou and Westinghouse to

34

5, 29732988, 2005 Stratospheric HALOE  

E-Print Network (OSTI)

ACPD 5, 2973­2988, 2005 Stratospheric HALOE climatology J.-U. Groo� and J. M. Russell III Title and Physics Discussions Technical note: A stratospheric climatology for O3, H2O and CH4 derived from HALOE­2988, 2005 Stratospheric HALOE climatology J.-U. Groo� and J. M. Russell III Title Page Abstract Introduction

Paris-Sud XI, Université de

35

Halogenated naphthyl methoxy piperidines for mapping serotonin transporter sites  

DOE Patents (OSTI)

Halogenated naphthyl methoxy piperidines having a strong affinity for the serotonin transporter are disclosed. Those compounds can be labeled with positron-emitting and/or gamma emitting halogen isotopes by a late step synthesis that maximizes the useable lifeterm of the label. The labeled compounds are useful for localizing serotonin transporter sites by positron emission tomography and/or single photon emission computed tomography.

Goodman, Mark M. (Atlanta, GA); Faraj, Bahjat (Lithonia, GA)

1999-01-01T23:59:59.000Z

36

Halogenated naphthyl methoxy piperidines for mapping serotonin transporter sites  

DOE Patents (OSTI)

Halogenated naphthyl methoxy piperidines having a strong affinity for the serotonin transporter are disclosed. Those compounds can be labeled with positron-emitting and/or gamma emitting halogen isotopes by a late step synthesis that maximizes the useable lifeterm of the label. The labeled compounds are useful for localizing serotonin transporter sites by positron emission tomography and/or single photon emission computed tomography.

Goodman, M.M.; Faraj, B.

1999-07-06T23:59:59.000Z

37

Treatment of halogen-containing waste and other waste materials  

DOE Patents (OSTI)

A process is described for treating a halogen-containing waste material. The process provides a bath of molten glass containing a sacrificial metal oxide capable of reacting with a halogen in the waste material. The sacrificial metal oxide is present in the molten glass in at least a stoichiometric amount with respect to the halogen in the waste material. The waste material is introduced into the bath of molten glass to cause a reaction between the halogen in the waste material and the sacrificial metal oxide to yield a metal halide. The metal halide is a gas at the temperature of the molten glass. The gaseous metal halide is separated from the molten glass and contacted with an aqueous scrubber solution of an alkali metal hydroxide to yield a metal hydroxide or metal oxide-containing precipitate and a soluble alkali metal halide. The precipitate is then separated from the aqueous scrubber solution. The molten glass containing the treated waste material is removed from the bath as a waste glass. The process of the invention can be used to treat all types of waste material including radioactive wastes. The process is particularly suited for separating halogens from halogen-containing wastes. 3 figs.

Forsberg, C.W.; Beahm, E.C.; Parker, G.W.

1997-03-18T23:59:59.000Z

38

Treatment of halogen-containing waste and other waste materials  

DOE Patents (OSTI)

A process for treating a halogen-containing waste material. The process provides a bath of molten glass containing a sacrificial metal oxide capable of reacting with a halogen in the waste material. The sacrificial metal oxide is present in the molten glass in at least a stoichiometric amount with respect to the halogen in the waste material. The waste material is introduced into the bath of molten glass to cause a reaction between the halogen in the waste material and the sacrificial metal oxide to yield a metal halide. The metal halide is a gas at the temperature of the molten glass. The gaseous metal halide is separated from the molten glass and contacted with an aqueous scrubber solution of an alkali metal hydroxide to yield a metal hydroxide or metal oxide-containing precipitate and a soluble alkali metal halide. The precipitate is then separated from the aqueous scrubber solution. The molten glass containing the treated waste material is removed from the bath as a waste glass. The process of the invention can be used to treat all types of waste material including radioactive wastes. The process is particularly suited for separating halogens from halogen-containing wastes.

Forsberg, Charles W. (Oak Ridge, TN); Beahm, Edward C. (Oak Ridge, TN); Parker, George W. (Concord, TN)

1997-01-01T23:59:59.000Z

39

What Light Bulbs Do You Use in Your Home? | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

What Light Bulbs Do You Use in Your Home? What Light Bulbs Do You Use in Your Home? What Light Bulbs Do You Use in Your Home? June 1, 2012 - 2:28pm Addthis Earlier this week, Eric Barendsen posted about the differences in costs between traditional and energy efficient light bulbs. Several people already chimed in on the original post. (Thanks a bunch for sharing!) But for today's question of the week, we're wondering: What light bulbs do you use in your own home? You have the chance to share your thoughts on a question about energy efficiency or renewable energy for consumers. E-mail your responses to the Energy Saver team at consumer.webmaster@nrel.gov. Addthis Related Articles Are You Prepared for a Blackout? Lighting Choices Save You Money. Energy-efficient light bulbs are available in a wide variety of sizes and shapes.

40

Symmetry Projected Density Functional Theory and Neutron Halo’s  

E-Print Network (OSTI)

The appearance of halo phenomena near the drip line nuclei has challenged our traditional understanding of the nuclei as an incompressible charged liquid drop and extended nuclear physics to low density and inhomogeneous system, where the coupling to the continuum has to be treated in a consistent way. Recently Relativistic Hartree Bogoliubov (RHB) theory in the continuum has been applied successfully to the description of halo phenomena in light and medium heavy nuclei [1, 2, 3]. This theory provides a self-consistent treatment of pairing correlation in the presence of the continuum and allows a microscopic description of halo phenomena in the framework of density functional theory. Essential conditions for the formation of a neutron halo have been found: (a) the Fermi surface of the neutrons has to

unknown authors

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Bar-Halo Friction in Galaxies III: Halo Density Changes  

E-Print Network (OSTI)

The predicted central densities of dark matter halos in LCDM models exceed those observed in some galaxies. Weinberg & Katz argue that angular momentum transfer from a rotating bar in the baryonic disk can lower the halo density, but they also contend that N-body simulations of this process will not reveal the true continuum result unless many more than the usual numbers of particles are employed. Adopting their simplified model of a rotating rigid bar in a live halo, I have been unable to find any evidence to support their contention. I find that both the angular momentum transferred and the halo density change are independent of the number of particles over the range usually employed up to that advocated by these authors. I show that my results do not depend on any numerical parameters, and that field methods perform equally with grid methods. I also identify the reasons that the required particle number suggested by Weinberg & Katz is excessive. I further show that when countervailing compression by baryonic settling is ignored, moderate bars can reduce the mean density of the inner halo by 20% - 30%. Long, massive, skinny bars can reduce the mean inner density by a factor ~10. The largest density reductions are achieved at the expense of removing most of the angular momentum likely to reside in the baryonic component. Compression of the halo by baryonic settling must reduce, and may even overwhelm, the density reduction achievable by bar friction.

J. A. Sellwood

2006-10-16T23:59:59.000Z

42

Magnesium Isotopes in Halo Stars  

E-Print Network (OSTI)

We have determined Mg isotope ratios in halo field dwarfs and giants in the globular cluster M71 based on high S/N high spectral resolution (R = 10$^5$) Keck HIRES spectra. Unlike previous claims of an important contribution from intermediate-mass AGB stars to the Galactic halo, we find that our $^{26}$Mg/$^{24}$Mg ratios can be explained by massive stars.

Jorge Melendez; Judith G. Cohen

2007-08-29T23:59:59.000Z

43

Bubbles in galactic haloes  

E-Print Network (OSTI)

We briefly discuss a possible interconnection of vertical HI structures observed in the Milky Way Galaxy with large scale blow-outs caused by the explosions of multiple clustered SNe. We argue that the observed OB associations can produce only about 60 such events, or approximately one chimney per 3 kpc$^2$ within the solar circle. We also discuss the overall properties of HI shells in nearby face-on galaxies and the distribution of H$\\alpha$ and dust in edge-on galaxies. We argue that the presence of dust in galactic haloes may indicate that radiation pressure is the most probable mechanism capable of transporting dust to large heights above the galactic plane. In order to make this possible, the galactic magnetic field must have a strong vertical component. We mention that SNe explosions can initiate the Parker instability which in turn creates large scale magnetic loops with a strong vertical component. Recent observations of nearby edge-on galaxies favour this suggestion.

Shchekinov, Yu A; Schröer, A; Steinacker, A; Shchekinov, Yu. A.

2001-01-01T23:59:59.000Z

44

Bubbles in galactic haloes  

E-Print Network (OSTI)

We briefly discuss a possible interconnection of vertical HI structures observed in the Milky Way Galaxy with large scale blow-outs caused by the explosions of multiple clustered SNe. We argue that the observed OB associations can produce only about 60 such events, or approximately one chimney per 3 kpc$^2$ within the solar circle. We also discuss the overall properties of HI shells in nearby face-on galaxies and the distribution of H$\\alpha$ and dust in edge-on galaxies. We argue that the presence of dust in galactic haloes may indicate that radiation pressure is the most probable mechanism capable of transporting dust to large heights above the galactic plane. In order to make this possible, the galactic magnetic field must have a strong vertical component. We mention that SNe explosions can initiate the Parker instability which in turn creates large scale magnetic loops with a strong vertical component. Recent observations of nearby edge-on galaxies favour this suggestion.

Yu. A. Shchekinov; R. -J. Dettmar; A. Schroeer; A. Steinacker

2001-02-09T23:59:59.000Z

45

Rotation of tokamak halo currents  

SciTech Connect

During tokamak disruptions, halo currents, which can be tenths of the total plasma current, can flow at the plasma edge along the magnetic field lines that intercept the chamber walls. Non-axisymmetric halo currents are required to maintain force balance as the plasma kinks when the edge safety factor drops to about two in a vertical displacement event. The plasma quickly assumes a definite toroidal velocity v{sub a}(r) with respect to that of the magnetic kink, v{sub k}, where v{sub a}(r) is set by the radial electric field required for ambipolarity. The plasma velocity, v{sub pl}=v{sub a}+v{sub k}, near the edge is influenced by the interaction with neutrals and with the potential in the halo required for quasi-neutrality on open magnetic field lines, and the plasma velocity in the core is influenced by external error fields. When plasma effects dominate magnetic locking, the magnetic kink should rotate at a diamagnetic speed of either the edge or the core. If the magnetic field lines of the halo plasma intercept the wall at locations of very different electrical conductivity, the toroidal rotation of the halo currents can intermittently stall at wall locations of high conductivity. Such stalling is seen in experiments. The toroidal phase difference between the stalled halo currents and the kink, which is expected to rotate smoothly, must satisfy {delta}{phi}<{+-}{pi}/2. A concern cited by ITER engineers is that the time varying force of the rotating halo could substantially increase the disruption loads on in-vessel components.

Boozer, Allen H. [Department of Applied Physics and Applied Mathematics Columbia University, New York, New York 10027 (United States)

2012-05-15T23:59:59.000Z

46

Halogenated 1'-methyl-1,2'-bipyrroles (MBPs) in the Norwestern Atlantic  

E-Print Network (OSTI)

Halogenated 1'-methyl-1,2'-bipyrroles (MBPs) are a distinctive class of marine organic compounds. They are naturally produced, they have a unique carbon structure, they are highly halogenated, and they bioaccumulate in ...

Pangallo, Kristin C

2009-01-01T23:59:59.000Z

47

What Light Bulbs Do You Use in Your Home? | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Light Bulbs Do You Use in Your Home? Light Bulbs Do You Use in Your Home? What Light Bulbs Do You Use in Your Home? June 1, 2012 - 2:28pm Addthis Earlier this week, Eric Barendsen posted about the differences in costs between traditional and energy efficient light bulbs. Several people already chimed in on the original post. (Thanks a bunch for sharing!) But for today's question of the week, we're wondering: What light bulbs do you use in your own home? You have the chance to share your thoughts on a question about energy efficiency or renewable energy for consumers. E-mail your responses to the Energy Saver team at consumer.webmaster@nrel.gov. Addthis Related Articles Are You Prepared for a Blackout? Do You Have Windows That Need Replacing? By taking simple steps to improve your home's energy efficiency, you can save up to 30 percent on your energy bill. | Infographic by Sarah Gerrity.

48

DOE Withdraws the Energy Star Label from 34 Compact Fluorescent Light Bulbs  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

the Energy Star Label from 34 Compact Fluorescent the Energy Star Label from 34 Compact Fluorescent Light Bulbs DOE Withdraws the Energy Star Label from 34 Compact Fluorescent Light Bulbs January 26, 2010 - 11:41am Addthis Washington, DC - On January 25th, the General Counsel notified 25 manufacturers that the Department of Energy has withdrawn their right to use the Energy Star label on 34 different models of compact fluorescent light bulbs (CFLs). The Department took this action after its off-the-shelf testing revealed that the affected models do not last as long in regular use as Energy Star certification would require. As a result, these manufacturers have been informed that they can no longer ship or sell any of the 34 models of CFLs bearing the Energy Star label on the bulb or its packaging. All compact fluorescent light bulbs use about 75 percent less energy and

49

Procedure for simulating divergent-light halos  

Science Journals Connector (OSTI)

Divergent-light halos are halos produced by light from nearby light sources, like street lamps being scattered by small crystals of ice floating in the air. The use of “brute-force”...

Gislén, Lars

2003-01-01T23:59:59.000Z

50

Method for selective dehalogenation of halogenated polyaromatic compounds  

DOE Patents (OSTI)

A method for dehalogenating halogenated polyaromatic compounds is provided wherein the polyaromatic compounds are mixed with a hydrogen donor solvent and a carbon catalyst in predetermined proportions, the mixture is maintained at a predetermined pressure, and the mixture is heated to a predetermined temperature and for a predetermined time.

Farcasiu, Malvina (Pittsburgh, PA); Petrosius, Steven C. (Library, PA)

1994-01-01T23:59:59.000Z

51

A Winning Light Bulb With the Potential to Save the Nation Billions |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

A Winning Light Bulb With the Potential to Save the Nation Billions A Winning Light Bulb With the Potential to Save the Nation Billions A Winning Light Bulb With the Potential to Save the Nation Billions August 4, 2011 - 3:09pm Addthis This 10-watt alternative LED bulb (which glows white when turned on) could save the nation about 35 terawatt-hours of electricity or $3.9 billion in one year and avoid 20 million metric tons of carbon emissions if every 60-watt incandescent bulb in the U.S. was replaced with the L Prize winner. | Photo Courtesy of Philips Lighting North America This 10-watt alternative LED bulb (which glows white when turned on) could save the nation about 35 terawatt-hours of electricity or $3.9 billion in one year and avoid 20 million metric tons of carbon emissions if every 60-watt incandescent bulb in the U.S. was replaced with the L Prize winner.

52

600 New Lights Bulbs to Improve Energy Efficiency at DOE | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

600 New Lights Bulbs to Improve Energy Efficiency at DOE 600 New Lights Bulbs to Improve Energy Efficiency at DOE 600 New Lights Bulbs to Improve Energy Efficiency at DOE November 18, 2010 - 10:30am Addthis Ingrid Kolb Director of the Office of Management Starting in September, the Department of Energy has been steadily replacing all 600 light fixtures under our Washington, D.C., Forrestal North Building canopy with state of the art Light Emitting Diode (LED) fixtures. Every new bulb now uses just 23 watts instead of 205 watts. That translates into almost half a million kilowatts hours saved every year. and will cut annual energy consumption at the Department of Energy Headquarters by about 1%. The final new LED fixture under the canopy was installed on October 28, but these lights are just part of a full program to reduce energy consumption

53

Westinghouse Pays $50,000 Civil Penalty to Resolve Light Bulb Efficiency  

NLE Websites -- All DOE Office Websites (Extended Search)

Westinghouse Pays $50,000 Civil Penalty to Resolve Light Bulb Westinghouse Pays $50,000 Civil Penalty to Resolve Light Bulb Efficiency Violations Westinghouse Pays $50,000 Civil Penalty to Resolve Light Bulb Efficiency Violations December 13, 2010 - 2:12pm Addthis The Department of Energy has successfully resolved the enforcement case against Westinghouse Lighting Corporation for failure to certify its light bulbs as compliant with DOE's federal efficiency requirements and for the sale of at least 29,000 general service fluorescent and medium base compact fluorescent lamps that used more energy than permitted by law. This case reflects DOE's renewed commitment to enforce the federal efficiency requirements systematically and fairly to level the competitive playing field and to ensure that American consumers are buying products that

54

DOE Requires Westinghouse to Cease Sales of Two Light Bulb Models and  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Requires Westinghouse to Cease Sales of Two Light Bulb Models Requires Westinghouse to Cease Sales of Two Light Bulb Models and Allows Sale of Another DOE Requires Westinghouse to Cease Sales of Two Light Bulb Models and Allows Sale of Another October 18, 2010 - 10:27am Addthis As a part of DOE's continuing enforcement action against Westinghouse Lighting Corporation, the company must cease sales of two light bulb models - medium based CFL basic model 15GLOBE/65/2 (Westinghouse product code 3800400) and general service fluorescent lamp model F40T12/CWE (Westinghouse product code 07521000) - because they do not meet DOE's energy efficiency standards. Based on test data provided by Westinghouse for basic model 15GLOBE/65/2, DOE has issued a Notice of Non-Compliance Determination to Westinghouse Lighting Corporation, requiring Westinghouse to halt sales and notify all

55

E-Print Network 3.0 - accessory olfactory bulb Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

search results for: accessory olfactory bulb Page: << < 1 2 3 4 5 > >> 1 Dcculopmentul Brain Rescurch. 70 (1W2) 279-22 O 1992 Elsevier Science Publishers B.V.All rights reserved...

56

A critical period for activity-dependent synaptic development during olfactory bulb adult neurogenesis  

E-Print Network (OSTI)

New neurons integrate in large numbers into the mature olfactory bulb circuit throughout life. The factors controlling the synaptic development of adult-born neurons and their connectivity remain essentially unknown. We ...

Kelsch, Wolfgang

57

Odor discrimination of "IP 3-" and “cAMP-increasing” odorants in the turtle olfactory bulb  

Science Journals Connector (OSTI)

The ability of the turtle olfactory system to discriminate between various odorants...P 3) in the olfactory bulb was examined by the cross-adaptation technique and analyzed by multidimensional sca...

Makoto Kashiwayanagi; Fumiko Nagasawa; Kouhei Inamura; Kenzo Kurihara

1996-03-01T23:59:59.000Z

58

DOE Requires Westinghouse to Cease Sales of Two Light Bulb Models and  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Requires Westinghouse to Cease Sales of Two Light Bulb Models Requires Westinghouse to Cease Sales of Two Light Bulb Models and Allows Sale of Another DOE Requires Westinghouse to Cease Sales of Two Light Bulb Models and Allows Sale of Another October 18, 2010 - 10:27am Addthis As a part of DOE's continuing enforcement action against Westinghouse Lighting Corporation, the company must cease sales of two light bulb models - medium based CFL basic model 15GLOBE/65/2 (Westinghouse product code 3800400) and general service fluorescent lamp model F40T12/CWE (Westinghouse product code 07521000) - because they do not meet DOE's energy efficiency standards. Based on test data provided by Westinghouse for basic model 15GLOBE/65/2, DOE has issued a Notice of Non-Compliance Determination to Westinghouse Lighting Corporation, requiring Westinghouse to halt sales and notify all

59

Interrelationships between air velocity and natural wet-bulb thermometer response  

E-Print Network (OSTI)

INTERRELATIONSHIPS BETWEEN AIR VFLOCITY ANO NATURAL WET-BULB THERMOMETER RESPONSE A Thesis by NATHAN GLENN JONES Submitted to the Graduate Colleqe of Texas ASM University i n partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE AUGUST 1983 Major Subject: Industrial Hygiene INTERRELATIONSHIPS BETWEEN AIR VELOCITY AND NATURAL WET-BULB THERMOMETER RESPONSE A Thesis by NATHAN GLENN JONES Approved as to style an content by: airman o ommittee er Member ~~' A~ Member...

Jones, Nathan Glenn

1983-01-01T23:59:59.000Z

60

Alkali-metal-halogen charge-exchange collisions  

Science Journals Connector (OSTI)

An approximate quasiclassical treatment is presented for calculating the cross sections for charge transfer from a neutral alkali-metal atom colliding with a halogen atom (chlorine or fluorine). The electron is treated by the time-dependent perturbation in the two-state approximation. The two states are the ground (or the first-excited) state of alkali-metal atom and the ground state of the halogen negative ion. Charge-transfer cross sections are calculated as a function of relative velocity (v) of collision between v=0.01 and 5 a.u. Qualitative features of these cross sections are compared with an earlier work on alkali-metal-oxygen collisions. An asymptotic formula at low velocities of collision v?0 is obtained, which compares with the earlier formula obtained by Bates. At higher velocities cross sections are found to vary as 1v2, as in the Born approximation.

D. Arora; J. E. Turner; P. G. Khubchandani

1976-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Potential Environmental Impacts from the Metals in Incandescent, Compact Fluorescent Lamp (CFL), and Light-Emitting Diode (LED) Bulbs  

Science Journals Connector (OSTI)

Artificial lighting systems are transitioning from incandescent to compact fluorescent lamp (CFL) and light-emitting diode (LED) bulbs in response to the U.S. Energy Independence and Security Act and the EU Ecodesign Directive, which leads to energy savings and reduced greenhouse gas emissions. ... The CFLs and LEDs have higher resource depletion and toxicity potentials than the incandescent bulb due primarily to their high aluminum, copper, gold, lead, silver, and zinc. ... mercury pollution; redn. in electricity demand from the substitution of incandescent bulbs with fluorescents leads to reduced mercury emissions during the use of the bulb. ...

Seong-Rin Lim; Daniel Kang; Oladele A. Ogunseitan; Julie M. Schoenung

2012-12-13T23:59:59.000Z

62

Spatial assessment of net mercury emissions from the use of fluorescent bulbs  

SciTech Connect

While fluorescent lighting is an important technology for reducing electrical energy demand, mercury used in the bulbs is an ongoing concern. Using state and country level data, net emissions of mercury from the marginal use of fluorescent lightbulbs are examined for a base year of 2004 for each of the 50 United States and 130 countries. Combustion of coal for electric power generation is generally the largest source of atmospheric mercury pollution; reduction in electricity demand from the substitution of incandescent bulbs with fluorescents leads to reduced mercury emissions during the use of the bulb. This analysis considers the local mix of power sources, coal quality, thermal conversion efficiencies, distribution losses, and any mercury control technologies that might be in place. Emissions of mercury from production and end-of-life treatment of the bulbs are also considered, providing a life-cycle perspective. Net reductions in mercury over the entire life cycle range from -1.2 to 97 mg per bulb depending on the country. The consequences for atmospheric mercury emissions of several policy scenarios are also discussed. 46 refs., 4 figs., 3 tabs.

Matthew J. Eckelman; Paul T. Anastas; Julie B. Zimmerman [Yale University, New Haven, CT (United States). Department of Chemical Engineering

2008-11-15T23:59:59.000Z

63

Bars and Dark Matter Halo Cores  

E-Print Network (OSTI)

Self-consistent bars that form in galaxies embedded within cuspy halos are unable to flatten the cusp. Short bars form in models with quasi-flat rotation curves. They lose angular momentum to the halo through dynamical friction, but the continuous concentration of mass within the disk as the bar grows actually compresses the halo further, overwhelming any density reduction due to the modest angular momentum transfer to the halo. Thus the Weinberg-Katz proposed solution to the non-existence of the predicted cuspy halos from CDM simulations would seem to be unworkable. I also find that the concerns over the performance of N-body codes raised by these authors do not apply to the methods used here.

J. A. Sellwood

2002-10-03T23:59:59.000Z

64

Preliminary assessment of halogenated alkanes as vapor-phase tracers  

SciTech Connect

New tracers are needed to evaluate the efficiency of injection strategies in vapor-dominated environments. One group of compounds that seems to meet the requirements for vapor-phase tracing are the halogenated alkanes (HCFCs). HCFCs are generally nontoxic, and extrapolation of tabulated thermodynamic data indicate that they will be thermally stable and nonreactive in a geothermal environment. The solubilities and stabilities of these compounds, which form several homologous series, vary according to the substituent ratios of fluorine, chlorine, and hydrogen. Laboratory and field tests that will further define the suitability of HCFCs as vapor-phase tracers are under way.

Adams, Michael C.; Moore, Joseph N.; Hirtz, Paul

1991-01-01T23:59:59.000Z

65

Why Did the LED Light Bulb Cross the Road? | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Why Did the LED Light Bulb Cross the Road? Why Did the LED Light Bulb Cross the Road? Why Did the LED Light Bulb Cross the Road? January 24, 2012 - 1:31pm Addthis Big Bill and Little Bill are here to talk with you about energy efficiency on behalf of Energy Impact Illinois. Roland Risser Roland Risser Program Director, Building Technologies Office How can I participate? You can view all of Big Bill and Little Bill's videos on the Energy Bill's YouTube channel. Everyone knows that laughter is good for you. Studies suggest it can buffer stress and increase your resistance to disease. Also, it just feels great to laugh. Advertisers have long used the allure of laughter to sell their products, and many Americans tune in to the Super Bowl just to chuckle at the funny commercials. However, when it comes to selling people on smart

66

Consumer Light Bulb Changes: Briefing and Resources for Media and Retailers  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Briefing for Media and Retailers - Lighting eere.energy.gov Briefing for Media and Retailers - Lighting eere.energy.gov 1 Consumer Light Bulb Changes: Briefing and Resources for Media and Retailers Briefing for Media and Retailers - Lighting eere.energy.gov 2 * Briefing: - To schedule interviews, please contact DOE Public Affairs at 202-586-4940 * Terms: - Lumens: Commonly a measure of brightness (technically "luminous flux") - CFL: Compact Fluorescent Lamp: The curly fluorescent bulbs - LED: Light Emitting Diode: more recently emerging technology, also called "solid state lighting" as it is light produced by a solid-state (chip) device - General Service Incandescent Lamp: The most common residential light bulb in use, with a medium screw base, and a lumen range of 310 to 2,600 lumens

67

Why Did the LED Light Bulb Cross the Road? | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Why Did the LED Light Bulb Cross the Road? Why Did the LED Light Bulb Cross the Road? Why Did the LED Light Bulb Cross the Road? January 24, 2012 - 1:31pm Addthis Big Bill and Little Bill are here to talk with you about energy efficiency on behalf of Energy Impact Illinois. Roland Risser Roland Risser Program Director, Building Technologies Office How can I participate? You can view all of Big Bill and Little Bill's videos on the Energy Bill's YouTube channel. Everyone knows that laughter is good for you. Studies suggest it can buffer stress and increase your resistance to disease. Also, it just feels great to laugh. Advertisers have long used the allure of laughter to sell their products, and many Americans tune in to the Super Bowl just to chuckle at the funny commercials. However, when it comes to selling people on smart

68

How to upgrade your incandescent light bulbs Many people are choosing replacements for their standard incandescent light bulbs to save money or energy, because they've heard of new LED  

E-Print Network (OSTI)

for their standard incandescent light bulbs to save money or energy, because they've heard of new LED options to choose replacement light bulbs. You can save energy and money by replacing any standard incandescent from The Lighting Pattern Book for Homes, LRC 1993. Lighting Energy Use by Room BR · Note the type

Bystroff, Chris

69

Efficient and Regioselective Halogenations of 2-Amino-1,3-thiazoles with Copper Salts  

E-Print Network (OSTI)

Efficient and Regioselective Halogenations of 2-Amino-1,3-thiazoles with Copper Salts Fabrice G. Halogenations proceed easily in the presence of copper(I) or copper(II) chlorides, bromides, or iodides directly in solution or with supported copper halides. 1,3-Thiazole rings appear in many compounds that exhibit

Shen, Jun

70

Simulating the Gaseous Halos of Galaxies  

E-Print Network (OSTI)

Observations of local X-ray absorbers, high-velocity clouds, and distant quasar absorption line systems suggest that a significant fraction of baryons may reside in multi-phase, low-density, extended, ~100 kpc, gaseous halos around normal galaxies. We present a pair of high-resolution SPH (smoothed particle hydrodynamics) simulations that explore the nature of cool gas infall into galaxies, and the physical conditions necessary to support the type of gaseous halos that seem to be required by observations. The two simulations are identical other than their initial gas density distributions: one is initialized with a standard hot gas halo that traces the cuspy profile of the dark matter, and the other is initialized with a cored hot halo with a high central entropy, as might be expected in models with early pre-heating feedback. Galaxy formation proceeds in dramatically different fashions in these two cases. While the standard cuspy halo cools rapidly, primarily from the central region, the cored halo is quasi-stable for ~4 Gyr and eventually cools via the fragmentation and infall of clouds from ~100 kpc distances. After 10 Gyr of cooling, the standard halo's X-ray luminosity is ~100 times current limits and the resultant disk galaxy is twice as massive as the Milky Way. In contrast, the cored halo has an X-ray luminosity that is in line with observations, an extended cloud population reminiscent of the high-velocity cloud population of the Milky Way, and a disk galaxy with half the mass and ~50% more specific angular momentum than the disk formed in the low-entropy simulation. These results suggest that the distribution and character of halo gas provides an important testing ground for galaxy formation models and may be used to constrain the physics of galaxy formation.

Tobias Kaufmann; James S. Bullock; Ari Maller; Taotao Fang

2008-01-28T23:59:59.000Z

71

Frequently Asked Questions Information on Compact Fluorescent Light Bulbs (CFLs) and Mercury  

E-Print Network (OSTI)

Frequently Asked Questions Information on Compact Fluorescent Light Bulbs (CFLs) and Mercury emissions equivalent to those of more than 800,000 cars. Do CFLs contain mercury? CFLs contain a very small amount of mercury sealed within the glass tubing ­ an average of 5 milligrams ­ about the amount

Jia, Songtao

72

Volunteer Potato Density Influences Critical Time of Weed Removal in Bulb Onion  

E-Print Network (OSTI)

Volunteer Potato Density Influences Critical Time of Weed Removal in Bulb Onion Martin M. Williams II, Corey V. Ransom, and W. Mack Thompson* Volunteer potato is highly competitive with onion and few control tactics are effective for removing this weed from an onion crop. Both volunteer potato density

Sims, Gerald K.

73

Labeling energy cost on light bulbs lowers implicit discount rates Jihoon Min a  

E-Print Network (OSTI)

Analysis Labeling energy cost on light bulbs lowers implicit discount rates Jihoon Min a , Inês L 2013 Accepted 24 October 2013 Available online xxxx Keywords: Energy efficient lighting Implicit lighting technology and for low energy consumption. Greater willingness to pay for lower energy consumption

Michalek, Jeremy J.

74

Effects of low-dose heavy ions on embryonic development in mice and on melanocyte differentiation in the epidermis and hair bulb  

Science Journals Connector (OSTI)

......melanocytes and hair bulb melanocytes in the dorsal...relative humidity and 12 h of fluorescent light/day. Female mice...melanocytes and ventral hair bulb melanocytes did not necessarily...irradiation; 0.1 Gy led to a significant frequency...melanocytes and hair bulb melanocytes, and these......

Tomohisa Hirobe; Kiyomi Eguchi-Kasai; Kimihiko Sugaya; Masahiro Murakami

2013-05-01T23:59:59.000Z

75

Environmental Dependence of Dark Matter Halo Growth I: Halo Merger Rates  

E-Print Network (OSTI)

In an earlier paper we quantified the mean merger rate of dark matter haloes as a function of redshift z, descendant halo mass M0, and progenitor halo mass ratio xi using the Millennium simulation of the LCDM cosmology. Here we broaden that study and investigate the dependence of the merger rate of haloes on their surrounding environment. A number of local mass overdensity variables, both including and excluding the halo mass itself, are tested as measures of a halo's environment. The simple functional dependence on z, M0, and xi of the merger rate found in our earlier work is largely preserved in different environments, but we find that the overall amplitude of the merger rate has a strong positive correlation with the environmental densities. For galaxy-mass haloes, we find mergers to occur ~2.5 times more frequently in the densest regions than in voids at both z=0 and higher redshifts. Higher-mass haloes show similar trends. We present a fitting form for this environmental dependence that is a function of both mass and local density and is valid out to z=2. The amplitude of the progenitor (or conditional) mass function shows a similarly strong correlation with local overdensity, suggesting that the extended Press-Schechter model for halo growth needs to be modified to incorporate environmental effects.

Onsi Fakhouri; Chung-Pei Ma

2008-08-18T23:59:59.000Z

76

MODIFIED GRAVITY SPINS UP GALACTIC HALOS  

SciTech Connect

We investigate the effect of modified gravity on the specific angular momentum of galactic halos by analyzing the halo catalogs at z = 0 from high-resolution N-body simulations for a f(R) gravity model that meets the solar-system constraint. It is shown that the galactic halos in the f(R) gravity model tend to acquire significantly higher specific angular momentum than those in the standard {Lambda}CDM model. The largest difference in the specific angular momentum distribution between these two models occurs for the case of isolated galactic halos with mass less than 10{sup 11} h {sup -1} M {sub Sun }, which are likely least shielded by the chameleon screening mechanism. As the specific angular momentum of galactic halos is rather insensitive to other cosmological parameters, it can in principle be an independent discriminator of modified gravity. We speculate a possibility of using the relative abundance of low surface brightness galaxies (LSBGs) as a test of general relativity given that the formation of the LSBGs occurs in fast spinning dark halos.

Lee, Jounghun [Astronomy Program, Department of Physics and Astronomy, FPRD, Seoul National University, Seoul 151-747 (Korea, Republic of)] [Astronomy Program, Department of Physics and Astronomy, FPRD, Seoul National University, Seoul 151-747 (Korea, Republic of); Zhao, Gong-Bo [National Astronomy Observatories, Chinese Academy of Science, Beijing 100012 (China)] [National Astronomy Observatories, Chinese Academy of Science, Beijing 100012 (China); Li, Baojiu [Institute of Computational Cosmology, Department of Physics, Durham University, Durham DH1 3LE (United Kingdom)] [Institute of Computational Cosmology, Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Koyama, Kazuya, E-mail: jounghun@astro.snu.ac.kr [Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth, PO1 3FX (United Kingdom)] [Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth, PO1 3FX (United Kingdom)

2013-01-20T23:59:59.000Z

77

Chem 115Lithium-Halogen ExchangeMyers RLi + R'X RX + R'Li  

E-Print Network (OSTI)

Chem 115Lithium-Halogen ExchangeMyers RLi + R'X RX + R'Li Lithium-halogen exchange reactions are essentially inert. 2 t-BuLi t-BuI + RLi t-BuLi isobutene + isobutane + LiI Lithium-halogen exchange reactions, and lithium iodide. H OEtBr H H OEtLi H1.1 eq n-BuLi Et2O, !80 °C Lau, K. S.; Schlosser, M. J. Org. Chem. 1978

78

Stability of BEC galactic dark matter halos  

E-Print Network (OSTI)

In this paper we show that spherically symmetric BEC dark matter halos, with the $\\sin r/r$ density profile, that accurately fit galactic rotation curves and represent a potential solution to the cusp-core problem are unstable. We do this by introducing back the density profiles into the fully time-dependent Gross-Pitaevskii-Poisson system of equations. Using numerical methods to track the evolution of the system, we found that these galactic halos lose mass at an approximate rate of half of its mass in a time scale of dozens of Myr. We consider this time scale is enough as to consider these halos are unstable and unlikely to be formed. We provide some arguments to show that this behavior is general and discuss some other drawbacks of the model that restrict its viability.

F. S. Guzman; F. D. Lora-Clavijo; J. J. Gonzalez-Aviles; F. J. Rivera-Paleo

2013-08-22T23:59:59.000Z

79

The Impact of Theoretical Uncertainties in the Halo Mass Function and Halo Bias on Precision Cosmology  

Science Journals Connector (OSTI)

We study the impact of theoretical uncertainty in the dark matter halo mass function and halo bias on dark energy constraints from imminent galaxy cluster surveys. We find that for an optical cluster survey like the Dark Energy Survey, the accuracy required on the predicted halo mass function to make it an insignificant source of error on dark energy parameters is ?1%. The analogous requirement on the predicted halo bias is less stringent (?5%), particularly if the observable-mass distribution can be well constrained by other means. These requirements depend upon survey area but are relatively insensitive to survey depth. The most stringent requirements are likely to come from a survey over a significant fraction of the sky that aims to observe clusters down to relatively low mass, M th ? 1013.7 h –1 M ?; for such a survey, the mass function and halo bias must be predicted to accuracies of ?0.5% and ?1%, respectively. These accuracies represent a limit on the practical need to calibrate ever more accurate halo mass and bias functions. We find that improving predictions for the mass function in the low-redshift and low-mass regimes is the most effective way to improve dark energy constraints.

Hao-Yi Wu; Andrew R. Zentner; Risa H. Wechsler

2010-01-01T23:59:59.000Z

80

The Impact of Theoretical Uncertainties in the Halo Mass Function and Halo  

SciTech Connect

We study the impact of theoretical uncertainty in the dark matter halo mass function and halo bias on dark energy constraints from imminent galaxy cluster surveys. We find that for an optical cluster survey like the Dark Energy Survey, the accuracy required on the predicted halo mass function to make it an insignificant source of error on dark energy parameters is {approx}1%. The analogous requirement on the predicted halo bias is less stringent ({approx}5%), particularly if the observable-mass distribution can be well constrained by other means. These requirements depend upon survey area but are relatively insensitive to survey depth. The most stringent requirements are likely to come from a survey over a significant fraction of the sky that aims to observe clusters down to relatively low mass, M{sub th}{approx} 10{sup 13.7} h{sup -1} M{sub sun}; for such a survey, the mass function and halo bias must be predicted to accuracies of {approx}0.5% and {approx}1%, respectively. These accuracies represent a limit on the practical need to calibrate ever more accurate halo mass and bias functions. We find that improving predictions for the mass function in the low-redshift and low-mass regimes is the most effective way to improve dark energy constraints.

Wu, Hao-Yi; Zentner, Andrew R.; Wechsler, Risa H.; /KIPAC, Menlo Park /SLAC /Pittsburgh U. /KIPAC, Menlo Park /SLAC

2010-06-04T23:59:59.000Z

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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81

Analysis of Halogen-Mercury Reactions in Flue Gas  

SciTech Connect

Oxidized mercury species may be formed in combustion systems through gas-phase reactions between elemental mercury and halogens, such as chorine or bromine. This study examines how bromine species affect mercury oxidation in the gas phase and examines the effects of mixtures of bromine and chlorine on extents of oxidation. Experiments were conducted in a bench-scale, laminar flow, methane-fired (300 W), quartz-lined reactor in which gas composition (HCl, HBr, NO{sub x}, SO{sub 2}) and temperature profile were varied. In the experiments, the post-combustion gases were quenched from flame temperatures to about 350 C, and then speciated mercury was measured using a wet conditioning system and continuous emissions monitor (CEM). Supporting kinetic calculations were performed and compared with measured levels of oxidation. A significant portion of this report is devoted to sample conditioning as part of the mercury analysis system. In combustion systems with significant amounts of Br{sub 2} in the flue gas, the impinger solutions used to speciate mercury may be biased and care must be taken in interpreting mercury oxidation results. The stannous chloride solution used in the CEM conditioning system to convert all mercury to total mercury did not provide complete conversion of oxidized mercury to elemental, when bromine was added to the combustion system, resulting in a low bias for the total mercury measurement. The use of a hydroxylamine hydrochloride and sodium hydroxide solution instead of stannous chloride showed a significant improvement in the measurement of total mercury. Bromine was shown to be much more effective in the post-flame, homogeneous oxidation of mercury than chlorine, on an equivalent molar basis. Addition of NO to the flame (up to 400 ppmv) had no impact on mercury oxidation by chlorine or bromine. Addition of SO{sub 2} had no effect on mercury oxidation by chlorine at SO{sub 2} concentrations below about 400 ppmv; some increase in mercury oxidation was observed at SO{sub 2} concentrations of 400 ppmv and higher. In contrast, SO{sub 2} concentrations as low as 50 ppmv significantly reduced mercury oxidation by bromine, this reduction could be due to both gas and liquid phase interactions between SO{sub 2} and oxidized mercury species. The simultaneous presence of chlorine and bromine in the flue gas resulted in a slight increase in mercury oxidation above that obtained with bromine alone, the extent of the observed increase is proportional to the chlorine concentration. The results of this study can be used to understand the relative importance of gas-phase mercury oxidation by bromine and chlorine in combustion systems. Two temperature profiles were tested: a low quench (210 K/s) and a high quench (440 K/s). For chlorine the effects of quench rate were slight and hard to characterize with confidence. Oxidation with bromine proved sensitive to quench rate with significantly more oxidation at the lower rate. The data generated in this program are the first homogeneous laboratory-scale data on bromine-induced oxidation of mercury in a combustion system. Five Hg-Cl and three Hg-Br mechanisms, some published and others under development, were evaluated and compared to the new data. The Hg-halogen mechanisms were combined with submechanisms from Reaction Engineering International for NO{sub x}, SO{sub x}, and hydrocarbons. The homogeneous kinetics under-predicted the levels of mercury oxidation observed in full-scale systems. This shortcoming can be corrected by including heterogeneous kinetics in the model calculations.

Paula Buitrago; Geoffrey Silcox; Constance Senior; Brydger Van Otten

2010-01-01T23:59:59.000Z

82

Process for removing halogenated aliphatic and aromatic compounds from petroleum products  

DOE Patents (OSTI)

A process is described for removing halogenated aliphatic and aromatic compounds, e.g., polychlorinated biphenyls, from petroleum products by solvent extraction. The halogenated aliphatic and aromatic compounds are extracted from a petroleum product into a polar solvent by contacting the petroleum product with the polar solvent. The polar solvent is characterized by a high solubility for the extracted halogenated aliphatic and aromatic compounds, a low solubility for the petroleum product and considerable solvent power for polyhydroxy compound. The preferred polar solvent is dimethylformamide. A miscible compound, such as, water or a polyhydroxy compound, is added to the polar extraction solvent to increase the polarity of the polar extraction solvent. The halogenated aliphatic and aromatic compounds are extracted from the highly-polarized mixture of water or polyhydroxy compound and polar extraction solvent into a low polar or nonpolar solvent by contacting the water or polyhydroxy compound-polar solvent mixture with the low polar or nonpolar solvent. The halogenated aliphatic and aromatic compounds and the low polar or nonpolar solvent are separated by physical means, e.g., vacuum evaporation. The polar and nonpolar solvents are recovered from recycling. The process can easily be designed for continuous operation. Advantages of the process include that the polar solvent and a major portion of the nonpolar solvent can be recycled, the petroleum products are reclaimable and the cost for disposing of waste containing polychlorinated biphenyls is significantly reduced. 1 fig.

Googin, J.M.; Napier, J.M.; Travaglini, M.A.

1983-09-20T23:59:59.000Z

83

Red Galaxy Growth and the Halo Occupation Distribution  

E-Print Network (OSTI)

We have traced the past 7 Gyr of red galaxy stellar mass growth within dark matter halos. We have determined the halo occupation distribution, which describes how galaxies reside within dark matter halos, using the observed luminosity function and clustering of 40,696 0.2red galaxies in Bootes. Half of 10^{11.9} Msun/h halos host a red central galaxy, and this fraction increases with increasing halo mass. We do not observe any evolution of the relationship between red galaxy stellar mass and host halo mass, although we expect both galaxy stellar masses and halo masses to evolve over cosmic time. We find that the stellar mass contained within the red population has doubled since z=1, with the stellar mass within red satellite galaxies tripling over this redshift range. In cluster mass halos most of the stellar mass resides within satellite galaxies and the intra-cluster light, with a minority of the stellar mass residing within central galaxies. The stellar masses of the most luminous red central galaxies are proportional to halo mass to the power of a third. We thus conclude that halo mergers do not always lead to rapid growth of central galaxies. While very massive halos often double in mass over the past 7 Gyr, the stellar masses of their central galaxies typically grow by only 30%.

Michael J. I. Brown; Zheng Zheng; Martin White; Arjun Dey; Buell T. Jannuzi; Andrew J. Benson; Kate Brand; Mark Brodwin; Darren J. Croton

2008-04-15T23:59:59.000Z

84

IUPAC-NIST Solubility Data Series 68. Halogenated Aliphatic Hydrocarbon Compounds C3C14 With Water  

E-Print Network (OSTI)

IUPAC-NIST Solubility Data Series 68. Halogenated Aliphatic Hydrocarbon Compounds C3­C14 With Water 16, 1999 This volume covers the solubilities of halogenated aliphatic C3­C14 compounds with water, heavy water, and electrolyte solutions. All data were critically examined for their reliability and best

Magee, Joseph W.

85

Halo mass distribution reconstruction across the cosmic web  

E-Print Network (OSTI)

We study the relation between halo mass and its environment from a probabilistic perspective. We find that halo mass depends not only on local dark matter density, but also on non-local quantities such as the cosmic web environment and the halo-exclusion effect. Given these accurate relations, we have developed the HADRON-code (Halo mAss Distribution ReconstructiON), a technique which permits us to assign halo masses to a distribution of haloes in three-dimensional space. This can be applied to the fast production of mock galaxy catalogues, by assigning halo masses, and reproducing accurately the bias for different mass cuts. The resulting clustering of the halo populations agree well with that drawn from the BigMultiDark $N$-body simulation: the power spectra are within 1-$\\sigma$ up to scales of $k=0.2\\,h\\,{\\rm Mpc}^{-1}$, when using augmented Lagrangian perturbation theory based mock catalogues. Only the most massive haloes show a larger deviation. For these, we find evidence of the halo-exclusion effect. ...

Zhao, Cheng; Chuang, Chia-Hsun; Prada, Francisco; Yepes, Gustavo; Tao, Charling

2015-01-01T23:59:59.000Z

86

MODELING OBSERVATIONAL CONSTRAINTS FOR DARK MATTER HALOS  

SciTech Connect

Observations show that the underlying rotation curves at intermediate radii in spiral and low-surface-brightness galaxies are nearly universal. Further, in these same galaxies, the product of the central density and the core radius ({rho}{sub 0} r{sub 0}) is constant. An empirically motivated model for dark matter halos that incorporates these observational constraints is presented and shown to be in accord with the observations. A model fit to the observations of the galaxy cluster A611 shows that {rho}{sub 0} r{sub 0} for the dark matter halo in this more massive structure is larger by a factor of {approx}20 over that assumed for the galaxies. The model maintains the successful Navarro-Frenk-White form in the outer regions, although the well-defined differences in the inner regions suggest that modifications to the standard cold dark matter picture are required.

Hartwick, F. D. A. [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8W 3P6 (Canada)

2012-12-01T23:59:59.000Z

87

The Halo Stars in NGC 5128. III: An Inner-Halo Field and the Metallicity Distribution  

E-Print Network (OSTI)

We present new HST/WFPC2 (V,I) photometry for the red-giant stars in NGC 5128 at a projected distance of 8 kpc from the galaxy center, which probe a mixture of its inner halo and outer bulge. The color-magnitude diagram shows an old red-giant branch which is even broader in color than our two previously studied outer-halo fields (at 21 and 31 kpc), with significant numbers of stars extending to Solar metallicity and higher. The peak frequency of the metallicity distribution function (MDF) is at [m/H] ~ -0.4, with even fewer metal-poor stars than in the outer-halo fields. We find that the main features of the halo MDF can be reproduced by a simple chemical evolution model in which early star formation goes on simultaneously with an initial stage of rapid infall of very metal-poor gas, after which the infall dies away exponentially. A comparison with the MDF for the NGC 5128 globular clusters indicates that there is a clear decrease of specific frequency $S_N$ (number of clusters per unit halo light) with increasing metallicity, from S_N ~ 4-8 at [Fe/H] -1. This trend may indicate that globular cluster formation efficiency is a strong function of the metallicity of the protocluster gas.

W. E. Harris; G. L. H. Harris

2002-04-26T23:59:59.000Z

88

Dynamic Colloidal Stabilization by Nanoparticle Halos  

Science Journals Connector (OSTI)

We explore the conditions under which colloids can be stabilized by the addition of smaller particles. The largest repulsive barriers between colloids occur when the added particles repel each other with soft interactions, leading to an accumulation near the colloid surfaces. At lower densities these layers of mobile particles (nanoparticle halos) result in stabilization, but when too many are added, the interactions become attractive again. We systematically study these effects—accumulation repulsion, reentrant attraction, and bridging—by accurate integral equation techniques.

S. Karanikas and A. A. Louis

2004-12-07T23:59:59.000Z

89

LED bulbs technical specification and testing procedure for solar home systems  

Science Journals Connector (OSTI)

Abstract The definition of technical specifications and the corresponding laboratory procedures are necessary steps in order to assure the quality of the devices prior to be installed in Solar Home Systems (SHS). To clarify and unify criteria a European project supported the development of the Universal Technical Standard for Solar Home Systems (UTSfSHS). Its principles were to generate simple and affordable technical requirements to be optimized in order to facilitate the implementation of tests with basic and simple laboratory tools even on the same SHS electrification program countries. These requirements cover the main aspects of this type of installations and its lighting chapter was developed based on the most used technology at that time: fluorescent tubes and CFLs. However, with the consolidation of the new LED solid state lighting devices, particular attention is being given to this matter and new procedures are required. In this work we develop a complete set of technical specifications and test procedures that have been designed within the frame of the UTSfSHS, based on an intense review of the scientific and technical publications related to LED lighting and their practical application. They apply to lamp reliability, performance and safety under normal, extreme and abnormal operating conditions as a simple but complete quality meter tool for any LED bulb. These tests have been applied to a group of 14 low-cost direct current LED bulbs and the accomplishment of the proposed requirements is analyzed.

Alfonso Gago Calderón; Luis Narvarte Fernández; Luis Miguel Carrasco Moreno; Javier Serón Barba

2015-01-01T23:59:59.000Z

90

Mercury Lamps Recycling Fluorescent light-tubes, compact fluorescent bulbs, mercury and sodium vapor lamps, ultraviolet and  

E-Print Network (OSTI)

Mercury Lamps Recycling Fluorescent light-tubes, compact fluorescent bulbs, mercury and sodium vapor lamps, ultraviolet and HID (high-intensity discharge) lamps and all other mercury containing labeled for shipment to a recycling plant for mercury, glass and aluminum recovery. The beneficial re

Baker, Chris I.

91

Environmental Dependence of Cold Dark Matter Halo Formation  

E-Print Network (OSTI)

We use a high-resolution $N$-body simulation to study how the formation of cold dark matter (CDM) halos is affected by their environments, and how such environmental effects produce the age-dependence of halo clustering observed in recent $N$-body simulations. We estimate, for each halo selected at redshift $z=0$, an `initial' mass $M_{\\rm i}$ defined to be the mass enclosed by the largest sphere which contains the initial barycenter of the halo particles and within which the mean linear density is equal to the critical value for spherical collapse at $z=0$. For halos of a given final mass, $M_{\\rm h}$, the ratio $M_{\\rm i}/M_{\\rm h}$ has large scatter, and the scatter is larger for halos of lower final masses. Halos that form earlier on average have larger $M_{\\rm i}/M_{\\rm h}$, and so correspond to higher peaks in the initial density field than their final masses imply. Old halos are more strongly clustered than younger ones of the same mass because their initial masses are larger. The age-dependence of clustering for low-mass halos is entirely due to the difference in the initial/final mass ratio. Low-mass old halos are almost always located in the vicinity of big structures, and their old ages are largely due to the fact that their mass accretions are suppressed by the hot environments produced by the tidal fields of the larger structure. The age-dependence of clustering is weaker for more massive halos because the heating by large-scale tidal fields is less important.

H. Y. Wang; H. J. Mo; Y. P. Jing

2006-08-31T23:59:59.000Z

92

LED lamp or bulb with remote phosphor and diffuser configuration with enhanced scattering properties  

DOE Patents (OSTI)

An LED lamp or bulb is disclosed that comprises a light source, a heat sink structure and an optical cavity. The optical cavity comprises a phosphor carrier having a conversions material and arranged over an opening to the cavity. The phosphor carrier comprises a thermally conductive transparent material and is thermally coupled to the heat sink structure. An LED based light source is mounted in the optical cavity remote to the phosphor carrier with light from the light source passing through the phosphor carrier. A diffuser dome is included that is mounted over the optical cavity, with light from the optical cavity passing through the diffuser dome. The properties of the diffuser, such as geometry, scattering properties of the scattering layer, surface roughness or smoothness, and spatial distribution of the scattering layer properties may be used to control various lamp properties such as color uniformity and light intensity distribution as a function of viewing angle.

Tong, Tao; Le Toquin, Ronan; Keller, Bernd; Tarsa, Eric; Youmans, Mark; Lowes, Theodore; Medendorp, Jr., Nicholas W; Van De Ven, Antony; Negley, Gerald

2014-11-11T23:59:59.000Z

93

Nuclear induced breakup of halo nuclei H. Esbensen  

E-Print Network (OSTI)

Nuclear induced breakup of halo nuclei H. Esbensen Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 G. F. Bertsch Institute for Nuclear Theory, University of Washington, Seattle made in calculating the nuclear induced breakup of halo nuclei. We find that a truncated coupled

Bertsch George F.

94

Properties of gas in and around galaxy haloes  

Science Journals Connector (OSTI)

......subtracting the peculiar velocity of the halo. The peculiar velocity of the halo is calculated by taking the mass-weighted average velocity of all the gas particles...with the pressure map shows that the outflows...strengthened by SN-driven winds. Figure 7 As Fig......

Freeke van de Voort; Joop Schaye

2012-07-11T23:59:59.000Z

95

Effectsof ice-crystal structure on halo formation: cirrus cloud  

E-Print Network (OSTI)

Effectsof ice-crystal structure on halo formation: cirrus cloud experimental and ray campaign, four 220halo-producing cirrus clouds were studied jointly from a ground- based polarization lidar of the aircraft, which collecteda total of 84slides byimpaction, preserving the ice crystals for later microscopic

Takano, Yoshihide

96

THE COSMOGRID SIMULATION: STATISTICAL PROPERTIES OF SMALL DARK MATTER HALOS  

SciTech Connect

We present the results of the ''Cosmogrid'' cosmological N-body simulation suites based on the concordance LCDM model. The Cosmogrid simulation was performed in a 30 Mpc box with 2048{sup 3} particles. The mass of each particle is 1.28 Multiplication-Sign 10{sup 5} M{sub Sun }, which is sufficient to resolve ultra-faint dwarfs. We found that the halo mass function shows good agreement with the Sheth and Tormen fitting function down to {approx}10{sup 7} M{sub Sun }. We have analyzed the spherically averaged density profiles of the three most massive halos which are of galaxy group size and contain at least 170 million particles. The slopes of these density profiles become shallower than -1 at the innermost radius. We also find a clear correlation of halo concentration with mass. The mass dependence of the concentration parameter cannot be expressed by a single power law, however a simple model based on the Press-Schechter theory proposed by Navarro et al. gives reasonable agreement with this dependence. The spin parameter does not show a correlation with the halo mass. The probability distribution functions for both concentration and spin are well fitted by the log-normal distribution for halos with the masses larger than {approx}10{sup 8} M{sub Sun }. The subhalo abundance depends on the halo mass. Galaxy-sized halos have 50% more subhalos than {approx}10{sup 11} M{sub Sun} halos have.

Ishiyama, Tomoaki [Center for Computational Science, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8577 (Japan); Rieder, Steven; Portegies Zwart, Simon [Sterrewacht Leiden, Leiden University, P.O. Box 9513, 2300-RA Leiden (Netherlands); Makino, Junichiro [Graduate School of Science and Engineering, Tokyo Institute of Technology (Japan); Groen, Derek [Centre for Computational Science, Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ (United Kingdom); Nitadori, Keigo [RIKEN Advanced Institute for Computational Science (Japan); De Laat, Cees [Section System and Network Engineering, University of Amsterdam, Amsterdam (Netherlands); McMillan, Stephen [Department of Physics, Drexel University, Philadelphia, PA 19104 (United States); Hiraki, Kei [Department of Creative Informatics, Graduate School of Information Science and Technology, the University of Tokyo (Japan); Harfst, Stefan, E-mail: ishiyama@ccs.tsukuba.ac.jp [Center for Astronomy and Astrophysics, Technical University Berlin, Hardenbergstr. 36, D-10623 Berlin (Germany)

2013-04-20T23:59:59.000Z

97

MACHO (MAssive Compact Halo Objects) Data  

DOE Data Explorer (OSTI)

The primary aim of the MACHO Project is to test the hypothesis that a significant fraction of the dark matter in the halo of the Milky Way is made up of objects like brown dwarfs or planets: these objects have come to be known as MACHOs, for MAssive Compact Halo Objects. The signature of these objects is the occasional amplification of the light from extragalactic stars by the gravitational lens effect. The amplification can be large, but events are extremely rare: it is necessary to monitor photometrically several million stars for a period of years in order to obtain a useful detection rate. For this purpose MACHO has a two channel system that employs eight CCDs, mounted on the 50 inch telescope at Mt. Stromlo. The high data rate (several GBytes per night) is accommodated by custom electronics and on-line data reduction. The Project has taken more than 27,000 images with this system since June 1992. Analysis of a subset of these data has yielded databases containing light curves in two colors for 8 million stars in the LMC and 10 million in the bulge of the Milky Way. A search for microlensing has turned up four candidates toward the Large Magellanic Cloud and 45 toward the Galactic Bulge. The web page for data provides links to MACHO Project data portals and various specialized interfaces for viewing or searching the data. (Specialized Interface)

98

Spin alignment of dark matter haloes in filaments and walls  

E-Print Network (OSTI)

The MMF technique is used to segment the cosmic web as seen in a cosmological N-body simulation into wall-like and filament-like structures. We find that the spins and shapes of dark matter haloes are significantly correlated with each other and with the orientation of their host structures. The shape orientation is such that the halo minor axes tend to lie perpendicular to the host structure, be it a wall or filament. The orientation of the halo spin vector is mass dependent. Low mass haloes in walls and filaments have a tendency to have their spins oriented within the parent structure, while higher mass haloes in filaments have spins that tend to lie perpendicular to the parent structure.

Miguel A. Aragón-Calvo; Rien van de Weygaert; Bernard J. T. Jones; J. M. Thijs van der Hulst

2006-10-09T23:59:59.000Z

99

SUBSTRUCTURE IN THE STELLAR HALOS OF THE AQUARIUS SIMULATIONS  

SciTech Connect

We characterize the substructure in the simulated stellar halos of Cooper et al. which were formed by the disruption of satellite galaxies within the cosmological N-body simulations of galactic halos of the Aquarius project. These stellar halos exhibit a wealth of tidal features: broad overdensities and very narrow faint streams akin to those observed around the Milky Way. The substructures are distributed anisotropically on the sky, a characteristic that should become apparent in the next generation of photometric surveys. The normalized RMS of the density of stars on the sky appears to be systematically larger for our halos compared with the value estimated for the Milky Way from main-sequence turnoff stars in the Sloan Digital Sky Survey. We show that this is likely to be due in part to contamination by faint QSOs and redder main-sequence stars, and might suggest that {approx}10% of the Milky Way halo stars have formed in situ.

Helmi, Amina [Kapteyn Astronomical Institute, University of Groningen, P.O. Box 800, 9700 AV Groningen (Netherlands); Cooper, A. P.; Cole, S.; Frenk, C. S. [Institute for Computational Cosmology, Department of Physics, University of Durham, South Road, Durham DH1 3LE (United Kingdom); White, S. D. M. [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching (Germany); Navarro, J. F., E-mail: ahelmi@astro.rug.nl [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P 5C2 (Canada)

2011-05-20T23:59:59.000Z

100

Impending U.S. lighting standards will boost market for halogen-infrared lamps: New product line expanding  

SciTech Connect

Many of the incandescent floodlights and spotlights manufactured today will not meet lighting efficiency standards taking effect in the US in 1995. As these models cease production, demand will grow for higher efficiency units to fill this huge market, which now totals about 100 million lamps per year. One prime contender is a new class of halogen lamps that use a spectrally selective coating to reflect heat back onto the filament, reducing the amount of electricity needed to generate light. GE Lighting`s Halogen-IR line is the only series of such lamps currently available to replace the conventional floodlights and spotlights that will be banned by the new standards. Other manufacturers may adopt the technology, however, and the Japanese producer Ushio already sells in the US a line of smaller halogen lamps with a similar heat-reflective coating. In terms of efficacy and lifetime, Halogen-IR lamps out perform standard incandescents and standard halogens, but fall far short of fluorescent, metal halide, and high-pressure sodium sources. These other lighting systems are more appropriate and cost-effective than incandescents for many ambient lighting applications. For accent lighting and other tasks that are best suited to incandescent lighting, however, the Halogen-IR lamp is often a superior choice.

Sardinsky, R.; Shepard, M.

1993-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Halogen adsorption on transition-metal surfaces: A case study of Cl on Ta(110)  

Science Journals Connector (OSTI)

Through a series of ab initio calculations, we not only predict the atomic and electronic structure of Cl on Ta(110), but also provide a quantitative basis for understanding a number of controversial questions regarding halogen adsorption on transition-metal surfaces. We demonstrate that a simple dipole layer model accurately describes the unexpected decrease in the work function upon halogen absorption, and that our proposed overlayer structure explains the one-dimensional streaking in the low-energy electron-diffraction pattern of the adsorbate-covered surface. An analysis of the electronic structure suggests that transition metals such as Ta look like simple metals from the point of view of highly electronegative adsorbates such as Cl.

Christine J. Wu and John E. Klepeis

1997-04-15T23:59:59.000Z

102

THE OVERDENSITY AND MASSES OF THE FRIENDS-OF-FRIENDS HALOS AND UNIVERSALITY OF HALO MASS FUNCTION  

SciTech Connect

The friends-of-friends algorithm (hereafter FOF) is a percolation algorithm which is routinely used to identify dark matter halos from N-body simulations. We use results from percolation theory to show that the boundary of FOF halos does not correspond to a single density threshold but to a range of densities close to a critical value that depends upon the linking length parameter, b. We show that for the commonly used choice of b = 0.2, this critical density is equal to 81.62 times the mean matter density. Consequently, halos identified by the FOF algorithm enclose an average overdensity which depends on their density profile (concentration) and therefore changes with halo mass, contrary to the popular belief that the average overdensity is {approx}180. We derive an analytical expression for the overdensity as a function of the linking length parameter b and the concentration of the halo. Results of tests carried out using simulated and actual FOF halos identified in cosmological simulations show excellent agreement with our analytical prediction. We also find that the mass of the halo that the FOF algorithm selects crucially depends upon mass resolution. We find a percolation-theory-motivated formula that is able to accurately correct for the dependence on number of particles for the mock realizations of spherical and triaxial Navarro-Frenk-White halos. However, we show that this correction breaks down when applied to the real cosmological FOF halos due to the presence of substructures. Given that abundance of substructure depends on redshift and cosmology, we expect that the resolution effects due to substructure on the FOF mass and halo mass function will also depend on redshift and cosmology and will be difficult to correct for in general. Finally, we discuss the implications of our results for the universality of the mass function.

More, Surhud; Kravtsov, Andrey V. [Kavli Institute for Cosmological Physics and Enrico Fermi Institute, University of Chicago, Chicago, IL 60637 (United States); Dalal, Neal [Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George Street, Toronto, Ontario M5S 3H8 (Canada); Gottloeber, Stefan, E-mail: surhud@kicp.uchicago.edu [Astrophysikalisches Institut Potsdam, An der Sternwarte 16, 14482 Potsdam (Germany)

2011-07-01T23:59:59.000Z

103

The chemistry of halogens on diamond: effects on growth and electron emission  

SciTech Connect

Diamond growth using halogenated precursors was studied in several diamond growth reactors. In a conventionao plasma reactor, diamond growth using the following gas mixtures was studied: CF{sub 4}/H{sub 2}, CH{sub 4}/H{sub 2}, CH{sub 3}F/H{sub 2}, and CH{sub 3}CL/H{sub 2}. Both the diamond growth measurements demonstrated ineffective transport of halogen radicals to the diamond surface during the growth process. In order to transport radical halogen species to the diamond surface during growth, a flow-tube reactor was constructed which minimized gas phase reactions. Also, the flow-tube reactor enabled pulsed gs transport to the diamond surface by fast-acting valves. Molecular beam mass spectroscopy was used to find condition which resulted in atomic hydrogen and/or atomic fluorine transport to the growing diamond surface. Although such conditions were found, they required very low pressures (0.5 Torr and below); these low pressures produce radical fluxes which are too low to sustain a reasonable diamond growth rate. The sequential reactor at Stanford was modified to add a halogen-growth step to the conventinoal atomic hydrogen/atomic carbon diamond growth cycle. Since the atomic fluorine, hydrogen and carbon environments are independent in the sequential reactor, the effect of fluorine on diamond growth could be studied independently of gas phase reactions. Although the diamond growth rate was increased by the use of fluorine, the film quality was seen to deteriorate as well as the substrate surface. Moreover, materials incompatibilities with fluorine significantly limited the use of fluorine in this reactor. A diamond growth model incorporating both gas phase and surface reactions was developed for the halocarbon system concurrent with the film growth efforts. In this report, we review the results of the growth experiments, the modeling, and additional experiments done to understand fluorine with diamond surfaces.

Hsu, W.L.; Pan, L.S.; Brown, L.A. [Sandia National Labs., Livermore, CA (United States)] [and others

1997-02-01T23:59:59.000Z

104

Spectral irradiance model for tungsten halogen lamps in 340-850 nm wavelength range  

SciTech Connect

We have developed a physical model for the spectral irradiance of 1 kW tungsten halogen incandescent lamps for the wavelength range 340-850 nm. The model consists of the Planck's radiation law, published values for the emissivity of tungsten, and a residual spectral correction function taking into account unknown factors of the lamp. The correction function was determined by measuring the spectra of a 1000 W, quartz-halogen, tungsten coiled filament (FEL) lamp at different temperatures. The new model was tested with lamps of types FEL and 1000 W, 120 V quartz halogen (DXW). Comparisons with measurements of two national standards laboratories indicate that the model can account for the spectral irradiance values of lamps with an agreement better than 1% throughout the spectral region studied. We further demonstrate that the spectral irradiance of a lamp can be predicted with an expanded uncertainty of 2.6% if the color temperature and illuminance values for the lamp are known with expanded uncertainties of 20 K and 2%, respectively. In addition, it is suggested that the spectral irradiance may be derived from resistance measurements of the filament with lamp on and off.

Ojanen, Maija; Kaerhae, Petri; Ikonen, Erkki

2010-02-10T23:59:59.000Z

105

Organic halogens in unpolluted waters and large bodies of water receiving bleach plant effluents  

SciTech Connect

In this paper the authors review and update recently performed studies of organic halogens in unpolluted waters and two large bodies of water receiving bleach plant effluents---Lake Vattern in Sweden and the Baltic Sea. All water samples contained measurable amounts of adsorbable organic halogens (AOX); the highest concentrations (up to 200 {mu}g Cl/L) were observed in humic lakes not exposed to any industrial discharges. Analysis of chlorophenols revealed that there is a long-distance transport ({gt} 100 km) of chloroguaiacols from bleach plants to remote parts of receiving waters. However, there was no evidence of chlorinated organics from bleach plants accumulating over several years in the water phase. One chlorophenol, 2,4,6-trichlorophenol, and its methylated analogue, 2,4,6-trichloroanisole, were also detected in surface waters considered to be unpolluted. Mass balance calculations showed that different processes in terrestrial environments make large contributions of AOX; enzyme-mediated chlorination of humic substances is a plausible explanation to the widespread occurrence of organic halogens.

Grimvall, A.; Jonsson, S.; Karlsson, S.; Savenhed, R.; Boren, H. (Dept. of Water and Environmental Studies, Linkoping Univ., S-58183 Linkoping (SE))

1991-05-01T23:59:59.000Z

106

ACCURATE MASS ESTIMATORS FOR NAVARRO-FRENK-WHITE HALOS  

SciTech Connect

We consider the problem of estimating the virial mass of a dark halo from the positions and velocities of a tracer population. Although a number of general tools are available, more progress can be made if we are able to specify the functional form of the halo potential (although not its normalization). Here, we consider the Navarro-Frenk-White halo and develop two simple estimators. We demonstrate their effectiveness against numerical simulations and use them to provide new mass estimates of Carina, Fornax, Sculptor, and Sextans dwarf spheroidal galaxies.

Evans, N. W.; Deason, A. J. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); An, J., E-mail: nwe@ast.cam.ac.uk, E-mail: ajd75@cam.ac.uk, E-mail: jinan@nao.cas.cn [National Astronomical Observatories, Chinese Academy of Sciences, A20 Datun Road, Chaoyang District, Beijing 100012 (China)

2011-04-01T23:59:59.000Z

107

Visualization of nitric oxide production in the mouse main olfactory bulb by a cell-trappable copper(II) fluorescent probe  

E-Print Network (OSTI)

We report the visualization of NO production using fluorescence in tissue slices of the mouse main olfactory bulb. This discovery was possible through the use of a novel, cell-trappable probe for intracellular nitric oxide ...

McQuade, Lindsey E.

108

REVISITING SCALING RELATIONS FOR GIANT RADIO HALOS IN GALAXY CLUSTERS  

SciTech Connect

Many galaxy clusters host megaparsec-scale radio halos, generated by ultrarelativistic electrons in the magnetized intracluster medium. Correlations between the synchrotron power of radio halos and the thermal properties of the hosting clusters were established in the last decade, including the connection between the presence of a halo and cluster mergers. The X-ray luminosity and redshift-limited Extended GMRT Radio Halo Survey provides a rich and unique dataset for statistical studies of the halos. We uniformly analyze the radio and X-ray data for the GMRT cluster sample, and use the new Planck Sunyaev-Zel'dovich (SZ) catalog to revisit the correlations between the power of radio halos and the thermal properties of galaxy clusters. We find that the radio power at 1.4 GHz scales with the cluster X-ray (0.1-2.4 keV) luminosity computed within R{sub 500} as P{sub 1.4}?L{sup 2.1±0.2}{sub 500}. Our bigger and more homogenous sample confirms that the X-ray luminous (L{sub 500} > 5 × 10{sup 44} erg s{sup –1}) clusters branch into two populations—radio halos lie on the correlation, while clusters without radio halos have their radio upper limits well below that correlation. This bimodality remains if we excise cool cores from the X-ray luminosities. We also find that P{sub 1.4} scales with the cluster integrated SZ signal within R{sub 500}, measured by Planck, as P{sub 1.4}?Y{sup 2.05±0.28}{sub 500}, in line with previous findings. However, contrary to previous studies that were limited by incompleteness and small sample size, we find that 'SZ-luminous' Y{sub 500} > 6 × 10{sup –5} Mpc{sup 2} clusters show a bimodal behavior for the presence of radio halos, similar to that in the radio-X-ray diagram. Bimodality of both correlations can be traced to clusters dynamics, with radio halos found exclusively in merging clusters. These results confirm the key role of mergers for the origin of giant radio halos, suggesting that they trigger the relativistic particle acceleration.

Cassano, R.; Brunetti, G.; Venturi, T.; Kale, R. [INAF/IRA, via Gobetti 101, I-40129 Bologna (Italy); Ettori, S. [INAF/Osservatorio Astronomico di Bologna, via Ranzani 1, I-40127 Bologna (Italy); Giacintucci, S. [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States); Pratt, G. W. [Laboratoire AIM, IRFU/Service dAstrophysique-CEA/DSM-CNRS-Université Paris Diderot, Bât. 709, CEA-Saclay, F-91191 Gif-sur-Yvette Cedex (France); Dolag, K. [University Observatory Munich, Scheinerstr. 1, D-81679 Munich (Germany); Markevitch, M. [Astrophysics Science Division, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

2013-11-10T23:59:59.000Z

109

Cores and cusps in warm dark matter halos  

SciTech Connect

The apparent presence of large core radii in Low Surface Brightness galaxies has been claimed as evidence in favor of warm dark matter. Here we show that WDM halos do not have cores that are large fractions of the halo size: typically, r{sub core}/r{sub 200}?<10{sup ?3}. This suggests an astrophysical origin for the large cores observed in these galaxies, as has been argued by other authors.

Villaescusa-Navarro, Francisco [IFIC, Universidad de Valencia-CSIC, E-46071, Valencia (Spain); Dalal, Neal, E-mail: villa@ific.uv.es, E-mail: neal@cita.utoronto.ca [Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George St., Toronto, ON, M5S3H8 (Canada)

2011-03-01T23:59:59.000Z

110

Possible existence of wormholes in the central regions of halos  

E-Print Network (OSTI)

An earlier study [Rahaman et al. (2014) & Kuhfittig (2014)] has demonstrated the possible existence of wormholes in the outer regions of the galactic halo, based on the Navarro-Frenk-White (NFW) density profile. This paper uses the Universal Rotation Curve (URC) dark matter model to obtain analogous results for the central parts of the halo. This result is an important compliment to the earlier result, thereby confirming the possible existence of wormholes in most of the spiral galaxies.

Farook Rahaman; P. Salucci; P. K. F. Kuhfittig; Saibal Ray; Mosiur Rahaman

2015-01-05T23:59:59.000Z

111

Modeling Angular-Momentum History in Dark-Matter Halos  

E-Print Network (OSTI)

We model the acquisition of spin by dark-matter halos in semi-analytic merger trees. We explore two different algorithms; one in which halo spin is acquired from the orbital angular momentum of merging satellites, and another in which halo spin is gained via tidal torquing on shells of material while still in the linear regime. We find that both scenarios produce the characteristic spin distribution of halos found in N-body simulations, namely, a log-normal distribution with mean ~0.04 and standard deviation ~0.5 in the log. A perfect match requires fine-tuning of two free parameters. Both algorithms also reproduce the general insensitivity of the spin distribution to halo mass, redshift and cosmology seen in N-body simulations. The spin distribution can be made strictly constant by physically motivated scalings of the free parameters. In addition, both schemes predict that halos which have had recent major mergers have systematically larger spin values. These algorithms can be implemented within semi-analytic models of galaxy formation based on merger trees. They yield detailed predictions of galaxy properties that strongly depend on angular momentum (such as size and surface brightness) as a function of merger history and environment.

Ariyeh H. Maller; Avishai Dekel; Rachel S. Somerville

2001-05-10T23:59:59.000Z

112

Process for removing halogenated aliphatic and aromatic compounds from petroleum products. [Polychlorinated biphenyls; methylene chloride; perchloroethylene; trichlorofluoroethane; trichloroethylene; chlorobenzene  

DOE Patents (OSTI)

A process for removing halogenated aliphatic and aromatic compounds, e.g., polychlorinated biphenyls, from petroleum products by solvent extraction. The halogenated aliphatic and aromatic compounds are extracted from a petroleum product into a polar solvent by contracting the petroleum product with the polar solvent. The polar solvent is characterized by a high solubility for the extracted halogenated aliphatic and aromatic compounds, a low solubility for the petroleum product and considerable solvent power for polyhydroxy compound. The preferred polar solvent is dimethylformamide. A miscible polyhydroxy compound, such as, water, is added to the polar extraction solvent to increase the polarity of the polar extraction solvent. The halogenated aliphatic and aromatic compounds are extracted from the highly-polarized mixture of polyhydroxy compound and polar extraction solvent into a low polar or nonpolar solvent by contacting the polyhydroxy compound-polar solvent mixture with the low polar or nonpolar solvent. The halogenated aliphatic and aromatic compounds in the low polar or nonpolar solvent by physical means, e.g., vacuum evaporation. The polar and nonpolar solvents are recovered for recycling. The process can easily be designed for continuous operation. Advantages of the process include that the polar solvent and a major portion of the nonpolar solvent can be recycled, the petroleum products are reclaimable and the cost for disposing of waste containing polychlorinated biphenyls is significantly reduced. 2 tables.

Googin, J.M.; Napier, J.M.; Travaglini, M.A.

1982-03-31T23:59:59.000Z

113

MAGNIFICATION BY GALAXY GROUP DARK MATTER HALOS  

SciTech Connect

We report on the detection of gravitational lensing magnification by a population of galaxy groups, at a significance level of 4.9{sigma}. Using X-ray-selected groups in the COSMOS 1.64 deg{sup 2} field, and high-redshift Lyman break galaxies as sources, we measure a lensing-induced angular cross-correlation between the samples. After satisfying consistency checks that demonstrate we have indeed detected a magnification signal, and are not suffering from contamination by physical overlap of samples, we proceed to implement an optimally weighted cross-correlation function to further boost the signal to noise of the measurement. Interpreting this optimally weighted measurement allows us to study properties of the lensing groups. We model the full distribution of group masses using a composite-halo approach, considering both the singular isothermal sphere and Navarro-Frenk-White profiles, and find our best-fit values to be consistent with those recovered using the weak-lensing shear technique. We argue that future weak-lensing studies will need to incorporate magnification along with shear, both to reduce residual systematics and to make full use of all available source information, in an effort to maximize scientific yield of the observations.

Ford, Jes; Hildebrandt, Hendrik; Van Waerbeke, Ludovic [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada); Leauthaud, Alexie; Tanaka, Masayuki [Institute for the Physics and Mathematics of the Universe, University of Tokyo, Chiba 277-8582 (Japan); Capak, Peter [NASA Spitzer Science Center, California Institute of Technology, 220-6 Caltech, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Finoguenov, Alexis [Max-Planck-Institut fuer Extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching (Germany); George, Matthew R. [Department of Astronomy, University of California, Berkeley, CA 94720 (United States); Rhodes, Jason [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

2012-08-01T23:59:59.000Z

114

Contouring Variability of the Penile Bulb on CT Images: Quantitative Assessment Using a Generalized Concordance Index  

SciTech Connect

Purpose: Within a multicenter study (DUE-01) focused on the search of predictors of erectile dysfunction and urinary toxicity after radiotherapy for prostate cancer, a dummy run exercise on penile bulb (PB) contouring on computed tomography (CT) images was carried out. The aim of this study was to quantitatively assess interobserver contouring variability by the application of the generalized DICE index. Methods and Materials: Fifteen physicians from different Institutes drew the PB on CT images of 10 patients. The spread of DICE values was used to objectively select those observers who significantly disagreed with the others. The analyses were performed with a dedicated module in the VODCA software package. Results: DICE values were found to significantly change among observers and patients. The mean DICE value was 0.67, ranging between 0.43 and 0.80. The statistics of DICE coefficients identified 4 of 15 observers who systematically showed a value below the average (p value range, 0.013 - 0.059): Mean DICE values were 0.62 for the 4 'bad' observers compared to 0.69 of the 11 'good' observers. For all bad observers, the main cause of the disagreement was identified. Average DICE values were significantly worse from the average in 2 of 10 patients (0.60 vs. 0.70, p < 0.05) because of the limited visibility of the PB. Excluding the bad observers and the 'bad' patients,' the mean DICE value increased from 0.67 to 0.70; interobserver variability, expressed in terms of standard deviation of DICE spread, was also reduced. Conclusions: The obtained values of DICE around 0.7 shows an acceptable agreement, considered the small dimension of the PB. Additional strategies to improve this agreement are under consideration and include an additional tutorial of the so-called bad observers with a recontouring procedure, or the recontouring by a single observer of the PB for all patients included in the DUE-01 study.

Carillo, Viviana [Department of Medical Physics, San Raffaele Scientific Institute, Milano (Italy)] [Department of Medical Physics, San Raffaele Scientific Institute, Milano (Italy); Cozzarini, Cesare [Department of Radiotherapy, San Raffaele Scientific Institute, Milano (Italy)] [Department of Radiotherapy, San Raffaele Scientific Institute, Milano (Italy); Perna, Lucia; Calandra, Mauro [Department of Medical Physics, San Raffaele Scientific Institute, Milano (Italy)] [Department of Medical Physics, San Raffaele Scientific Institute, Milano (Italy); Gianolini, Stefano [Medical Software Solutions GmbH, Hagendorn (Switzerland)] [Medical Software Solutions GmbH, Hagendorn (Switzerland); Rancati, Tiziana [Prostate Cancer Program, IRCCS National Institute of Cancer, Milano (Italy)] [Prostate Cancer Program, IRCCS National Institute of Cancer, Milano (Italy); Spinelli, Antonello Enrico [Department of Medical Physics, San Raffaele Scientific Institute, Milano (Italy)] [Department of Medical Physics, San Raffaele Scientific Institute, Milano (Italy); Vavassori, Vittorio [Department of Radiotherapy, Cliniche Gavazzeni Humanitas, Bergamo (Italy)] [Department of Radiotherapy, Cliniche Gavazzeni Humanitas, Bergamo (Italy); Villa, Sergio [Department of Radiotherapy 1, IRCCS National Institute of Cancer, Milano (Italy)] [Department of Radiotherapy 1, IRCCS National Institute of Cancer, Milano (Italy); Valdagni, Riccardo [Prostate Cancer Program, IRCCS National Institute of Cancer, Milano (Italy) [Prostate Cancer Program, IRCCS National Institute of Cancer, Milano (Italy); Department of Radiotherapy 1, IRCCS National Institute of Cancer, Milano (Italy); Fiorino, Claudio, E-mail: fiorino.claudio@hsr.it [Department of Medical Physics, San Raffaele Scientific Institute, Milano (Italy)] [Department of Medical Physics, San Raffaele Scientific Institute, Milano (Italy)

2012-11-01T23:59:59.000Z

115

PHYSICS DIVISION ESH BULLETIN 2004-01 1/5/04 OFFICES, SAFETY GUIDELINES  

E-Print Network (OSTI)

to these lamps. Energy Star® labeled torchiere floor lamps use compact fluorescent bulbs that burn much cooler fluorescent bulb which give the same amount of light as a 200 watt halogen bulb. Incidental Soldering. Most torchiere floor lamps use halogen bulbs that burn at temperatures exceeding 1,200 degrees F, hot

116

The shape of the invisible halo: N?body simulations on parallel supercomputers  

Science Journals Connector (OSTI)

We study the shapes of halos and the relationship to their angular momentum content by means of N?body (N?106) simulations. Results indicate that in relaxed halos with no apparent substructure: i.) The shape and orientation of the isodensity contours tends to persist throughout the virialized portion of the halo. ii.) Most (?70%) of the halos are prolate. iii.) The approximate direction of the angular momentum vector tends to persist throughout the halo. iv.) For spherical shells centered on the core of the halo the magnitude of the specific angular momentum is approximately proportional to their radius. v.) The shortest axis of the ellipsoid which approximates the shape of the halo tends to align with the rotation axis of the halo. This tendency is strongest in the fastest rotating halos.

M. S. Warren; W. H. Zurek; P. J. Quinn; J. K. Salmon

1991-01-01T23:59:59.000Z

117

Deoxybenzoin-Based Polyarylates as Halogen-Free Fire-Resistant Kenneth A. Ellzey, T. Ranganathan, Joseph Zilberman, E. Bryan Coughlin,*  

E-Print Network (OSTI)

, processing, and engineering of halogen-free, low heat release, fire-resistant materials present important with high carbon monoxide emis- sion.7,8 Ideal flame-retardant polymers would possess high thermal stabilityDeoxybenzoin-Based Polyarylates as Halogen-Free Fire-Resistant Polymers Kenneth A. Ellzey, T

118

Process for the solvent extraction for the radiolysis and dehalogenation of halogenated organic compounds in soils, sludges, sediments and slurries  

DOE Patents (OSTI)

A process of extracting halogenated organic compounds, and particularly PCBs, from soil, sediment, slurry, sludge and dehalogenating the compounds contacting a contaminated soil sample with an extraction medium of a mixture of an alkane and a water miscible alcohol. The organic compounds dissolve in the extraction medium which is separated from the soil by passing water upwardly through the soil. The extraction medium floats to the surface of the water and is separated. Thereafter, the extraction medium containing the halogenated organic contaminants is subjected to ionizing radiation to radiolytically dehalogenate the compounds.

Mincher, Bruce J. (3705 Creekside Dr., Idaho Falls, ID 83404); Curry, Randy Dale (1104 Merrill Ct., Columbia, MO 65203); Clevenger, Thomas E. (2512 Bluff Blvd., Columbia, MO 65201); Golden, Jeffry (12612 Cedarbrook La., Laurel, MD 20708)

2000-01-01T23:59:59.000Z

119

Merger Histories of Galaxy Halos and Implications for Disk Survival  

E-Print Network (OSTI)

We study the merger histories of galaxy dark matter halos using a high resolution LCDM N-body simulation. Our merger trees follow ~17,000 halos with masses M_0 = (10^11--10^13) Msun at z=0 and track accretion events involving objects as small as m = 10^10 Msun. We find that mass assembly is remarkably self-similar in m/M_0, and dominated by mergers that are ~10% of the final halo mass. While very large mergers, m > 0.4 M_0, are quite rare, sizeable accretion events, m ~ 0.1 M_0, are common. Over the last 10 Gyr, an overwhelming majority (~95%) of Milky Way-sized halos with M_0 = 10^12 Msun have accreted at least one object with greater total mass than the Milky Way disk (m > 5x10^10 Msun), and approximately 70% have accreted an object with more than twice that mass (m > 10^11 Msun). Our results raise serious concerns about the survival of thin-disk dominated galaxies within the current paradigm for galaxy formation in a CDM universe. In order to achieve a ~70% disk-dominated fraction in Milky Way-sized CDM halos, mergers involving m ~ 2x10^11 Msun objects must not destroy disks. Considering that most thick disks and bulges contain old stellar populations, the situation is even more restrictive: these mergers must not heat disks or drive gas into their centers to create young bulges.

Kyle R. Stewart; James S. Bullock; Risa H. Wechsler; Ariyeh H. Maller; Andrew R. Zentner

2007-11-30T23:59:59.000Z

120

Bar-halo Friction in Galaxies I: Scaling Laws  

E-Print Network (OSTI)

It has been known for some time that rotating bars in galaxies slow due to dynamical friction against the halo. However, recent attempts to use this process to place constraints on the dark matter density in galaxies and possibly also to drive dark matter out of the center have been challenged. This paper uses simplified numerical experiments to clarify several aspects of the friction mechanism. I explicitly demonstrate the Chandrasekhar scaling of the friction force with bar mass, halo density, and halo velocity dispersion. I present direct evidence that exchanges between the bar and halo orbits at major resonances are responsible for friction and study both individual orbits and the net changes at these resonances. I also show that friction alters the phase space density of particles in the vicinity of a major resonance, which is the reason the magnitude of the friction force depends on the prior evolution. I demonstrate that bar slow down can be captured correctly in simulations having modest spatial resolution and practicable numbers of particles. Subsequent papers in this series delineate the dark matter density that can be tolerated in halos of different density profiles.

J. A. Sellwood

2004-07-26T23:59:59.000Z

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121

Bar-Halo Friction in Galaxies II: Metastability  

E-Print Network (OSTI)

It is well-established that strong bars rotating in dense halos generally slow down as they lose angular momentum to the halo through dynamical friction. Angular momentum exchanges between the bar and halo particles take place at resonances. While some particles gain and others lose, friction arises when there is an excess of gainers over losers. This imbalance results from the generally decreasing numbers of particles with increasing angular momentum, and friction can therefore be avoided if there is no gradient in the density of particles across the major resonances. Here we show that anomalously weak friction can occur for this reason if the pattern speed of the bar fluctuates upwards. After such an event, the density of resonant halo particles has a local inflexion created by the earlier exchanges, and bar slowdown can be delayed for a long period; we describe this as a metastable state. We show that this behavior in purely collisionless N-body simulations is far more likely to occur in methods with adaptive resolution. We also show that the phenomenon could arise in nature, since bar-driven gas inflow could easily raise the bar pattern speed enough to reach the metastable state. Finally, we demonstrate that mild external, or internal, perturbations quickly restore the usual frictional drag, and it is unlikely therefore that a strong bar in a galaxy having a dense halo could rotate for a long period without friction.

J. A. Sellwood; Victor P. Debattista

2005-11-05T23:59:59.000Z

122

Lipopolysaccharide-QD Micelles Induce Marked Induction of TLR2 and Lipid Droplet Accumulation in Olfactory Bulb Microglia  

Science Journals Connector (OSTI)

Quantum dots (QD) were selected because they are among the most studied fluorescent nanoparticles for in vivo imaging,(18-20) but their effects on microglia have not been extensively explored. ... The fluorescence spectroscopy was observed on a fluorescence reader from Varian Cary Eclipse after an excitation at 365 nm with a window of emission between 500 and 700 nm. ... In the initial experiments using primary neural cultures from olfactory bulb, the exposure to LPS (100 ng/mL to 10 ?g/mL), QDs (1?5 nM) or LPS and QDs in combination for 24 h led to the formation of lipid droplets (LD). ...

Me?lanie Lalancette-He?bert; Alexandre Moquin; Angela O. Choi; Jasna Kriz; Dusica Maysinger

2010-05-11T23:59:59.000Z

123

Breaking the Disk/Halo Degeneracy with Gravitational Lensing  

E-Print Network (OSTI)

The degeneracy between the disk and the dark matter contribution to galaxy rotation curves remains an important uncertainty in our understanding of disk galaxies. Here we discuss a new method for breaking this degeneracy using gravitational lensing by spiral galaxies, and apply this method to the spiral lens B1600+434 as an example. The combined image and lens photometry constraints allow models for B1600+434 with either a nearly singular dark matter halo, or a halo with a sizable core. A maximum disk model is ruled out with high confidence. Further information, such as the circular velocity of this galaxy, will help break the degeneracies. Future studies of spiral galaxy lenses will be able to determine the relative contribution of disk, bulge, and halo to the mass in the inner parts of galaxies.

Ariyeh H. Maller; Luc Simard; Puragra Guhathakurta; Jens Hjorth; Andreas O. Jaunsen; Ricardo A. Flores; Joel R. Primack

1999-10-12T23:59:59.000Z

124

Neutron halo effect on direct neutron capture and photodisintegration  

Science Journals Connector (OSTI)

A novel effect of the neutron halo formation is presented for the direct radiative neutron capture where a p-wave neutron is captured into an s orbit with neutron halo by emitting an E1 ? ray. As an example, an enormous enhancement is demonstrated for the cross section of C12(n,?)13C(1/2+) at low energy in excellent agreement with a recent experiment. The S factor of the final state is evaluated. The inverse process, i.e., photo disintegration is discussed for an example of Be11. A sharp but nonresonant peak near the threshold is obtained as a result of the neutron halo in its anomalous ground state.

T. Otsuka; M. Ishihara; N. Fukunishi; T. Nakamura; M. Yokoyama

1994-05-01T23:59:59.000Z

125

The density profiles of hot galactic halo gas  

E-Print Network (OSTI)

Extended gas haloes around galaxies are a ubiquitous prediction of galaxy formation scenarios. However, the density profiles of this hot halo gas is virtually unknown, although various profiles have been suggested on theoretical grounds. In order to quantitatively address the gas profile, we compare galaxies from direct cosmological simulations with analytical solutions of the underlying gas equations. We find remarkable agreement between simulations and theoretical predictions. We present an expression for this gas profile with a non-trivial dependence on the total mass profile. This expression is useful when setting up equilibrium galaxy models for numerical experiments.

Steen H. Hansen; Jesper Sommer-Larsen

2006-06-13T23:59:59.000Z

126

Are the red halos of galaxies made of low-mass stars? Constraints from subdwarf star counts in the Milky Way halo  

E-Print Network (OSTI)

Surface photometry detections of red and exceedingly faint halos around galaxies have resurrected the old question of whether some non-negligible fraction of the missing baryons of the Universe could be hiding in the form of faint, hydrogen-burning stars. The optical/near-infrared colours of these red halos have proved very difficult to reconcile with any normal type of stellar population, but can in principle be explained by advocating a bottom-heavy stellar initial mass function. This implies a high stellar mass-to-light ratio and hence a substantial baryonic mass locked up in such halos. Here, we explore the constraints imposed by current observations of ordinary stellar halo subdwarfs on a putative red halo of low-mass stars around the Milky Way. Assuming structural parameters similar to those of the red halo recently detected in stacked images of external disk galaxies, we find that a smooth halo component with a bottom-heavy initial mass function is completely ruled out by current star count data for the Milky Way. All viable smooth red halo models with a density slope even remotely similar to that of the stacked halo moreover contain far too little mass to have any bearing on the missing-baryon problem. However, we note that these constraints can be sidestepped if the red halo stars are locked up in star clusters, and discuss potential observations of other nearby galaxies that may be able to put such scenarios to the test.

E. Zackrisson; C. Flynn

2008-09-17T23:59:59.000Z

127

Introduction The Fiber-Lite MI-150 is a 150 Watt quartz halogen fiber optic illuminator designed for general microscopy  

E-Print Network (OSTI)

Introduction ® The Fiber-Lite MI-150 is a 150 Watt quartz halogen fiber optic illuminator designed for general microscopy use. When used with specialty fiber optic cables the MI-150 illuminator can also Illuminator from the carton and retain the manual and any additional documents. ! Remove the fiber optic cable

Kleinfeld, David

128

Spatially resolved velocity maps of halo gas around two intermediate-redshift galaxies  

Science Journals Connector (OSTI)

......with the circular velocity of the halo, which is related to halo mass according to km s1...representing halo mass in units of 1012Mo...sightlines near G1 show a velocity width of deltav 90...Detailed H-I maps of nearby galaxy...absorption due to recycled winds (e.g. Oppenheimer......

Hsiao-Wen Chen; Jean-René Gauthier; Keren Sharon; Sean D. Johnson; Preethi Nair; Cameron J. Liang

2014-01-01T23:59:59.000Z

129

In situ thermally enhanced biodegradation of petroleum fuel hydrocarbons and halogenated organic solvents  

DOE Patents (OSTI)

An in situ thermally enhanced microbial remediation strategy and a method for the biodegradation of toxic petroleum fuel hydrocarbon and halogenated organic solvent contaminants are described. The method utilizes nonpathogenic, thermophilic bacteria for the thermal biodegradation of toxic and carcinogenic contaminants, such as benzene, toluene, ethylbenzene and xylenes, from fuel leaks and the chlorinated ethenes, such as trichloroethylene, chlorinated ethanes, such as 1,1,1-trichloroethane, and chlorinated methanes, such as chloroform, from past solvent cleaning practices. The method relies on and takes advantage of the pre-existing heated conditions and the array of delivery/recovery wells that are created and in place following primary subsurface contaminant volatilization efforts via thermal approaches, such as dynamic underground steam-electrical heating. 21 figs.

Taylor, R.T.; Jackson, K.J.; Duba, A.G.; Chen, C.I.

1998-05-19T23:59:59.000Z

130

In situ thermally enhanced biodegradation of petroleum fuel hydrocarbons and halogenated organic solvents  

DOE Patents (OSTI)

An in situ thermally enhanced microbial remediation strategy and a method for the biodegradation of toxic petroleum fuel hydrocarbon and halogenated organic solvent contaminants. The method utilizes nonpathogenic, thermophilic bacteria for the thermal biodegradation of toxic and carcinogenic contaminants, such as benzene, toluene, ethylbenzene and xylenes, from fuel leaks and the chlorinated ethenes, such as trichloroethylene, chlorinated ethanes, such as 1,1,1-trichloroethane, and chlorinated methanes, such as chloroform, from past solvent cleaning practices. The method relies on and takes advantage of the pre-existing heated conditions and the array of delivery/recovery wells that are created and in place following primary subsurface contaminant volatilization efforts via thermal approaches, such as dynamic underground steam-electrical heating.

Taylor, Robert T. (Livermore, CA); Jackson, Kenneth J. (San Leandro, CA); Duba, Alfred G. (Livermore, CA); Chen, Ching-I (Danville, CA)

1998-01-01T23:59:59.000Z

131

Red Halos of Galaxies - Reservoirs of Baryonic Dark Matter?  

E-Print Network (OSTI)

Deep optical/near-IR surface photometry of galaxies outside the Local Group have revealed faint and very red halos around objects as diverse as disk galaxies and starbursting dwarf galaxies. The colours of these structures are too extreme to be reconciled with stellar populations similar to those seen in the stellar halos of the Milky Way or M31, and alternative explanations like dust reddening, high metallicities or nebular emission are also disfavoured. A stellar population obeying an extremely bottom-heavy initial mass function (IMF), is on the other hand consistent with all available data. Because of its high mass-to-light ratio, such a population would effectively behave as baryonic dark matter and could account for some of the baryons still missing in the low-redshift Universe. Here, we give an overview of current red halo detections, alternative explanations for the origin of the red colours and ongoing searches for red halos around types of galaxies for which this phenomenon has not yet been reported. A number of potential tests of the bottom-heavy IMF hypothesis are also discussed.

E. Zackrisson; N. Bergvall; C. Flynn; G. Ostlin; G. Micheva; B. Caldwell

2007-08-06T23:59:59.000Z

132

MODELLING OF THE TOROIDAL ASYMMETRY OF POLOIDAL HALO CURRENTS  

E-Print Network (OSTI)

currents, and these can be of substantial magnitude. Of particular concern for tokamak design and operation is the observed toroidal asymmetry of the halo current distribution: such an asymmetric distribution leads to prob, since the force distribution on the conducting structures depends mainly on the `resistive distribution

133

Formation and evolution of CDM halos and their substructure  

E-Print Network (OSTI)

solution of the idealized problem complementary approach: hydro-dynamical simulations - computationally expensive, resolution relatively low - hydro is not trivial (SPH and grid codes often disagree, e.g. Agertz there is a cutoff at about 10-6 Msun due to free streaming small, "micro"-halos should forming around z=40

California at Santa Cruz, University of

134

The Star Formation History in the Andromeda Halo  

E-Print Network (OSTI)

I present the preliminary results of a program to measure the star formation history in the halo of the Andromeda galaxy. Using the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope, we obtained the deepest optical images of the sky to date, in a field on the southeast minor axis of Andromeda, 51 arcmin (11 kpc) from the nucleus. The resulting color-magnitude diagram (CMD) contains approximately 300,000 stars and extends more than 1.5 mag below the main sequence turnoff, with 50% completeness at V=30.7 mag. We interpret this CMD using comparisons to ACS observations of five Galactic globular clusters through the same filters, and through chi-squared fitting to a finely-spaced grid of calibrated stellar population models. We find evidence for a major (approximately 30%) intermediate-age (6-8 Gyr) metal-rich ([Fe/H] > -0.5) population in the Andromeda halo, along with a significant old metal-poor population akin to that in the Milky Way halo. The large spread in ages suggests that the Andromeda halo formed as a result of a more violent merging history than that in our own Milky Way.

Thomas M. Brown

2003-08-18T23:59:59.000Z

135

FIELD SCREENING FOR HALOGENATED VOLATILE ORGANIC COMPOUNDS: THE NEW X-WAND HVOC SCREENING DEVICE  

SciTech Connect

Western Research Institute (WRI) has developed new methodology and a test kit to screen soil or water samples for halogenated volatile organic compounds (HVOCs) in the field. The technology has been designated the X-Wand{trademark} screening tool. The new device uses a heated diode sensor that is commonly used to detect leaks of refrigerants from air conditioners, freezers, and refrigerators. This sensor is selective to halogens. It does not respond to volatile aromatic hydrocarbons, such as those in gasoline, and it is not affected by high humidity. In the current work, the heated diode leak detectors were modified further to provide units with rapid response and enhanced sensitivity. The limit of detection for trichloroethylene TCE in air is 0.1 mg/m{sup 3} (S/N = 2). The response to other HVOCS relative to TCE is similar. Variability between sensors and changes in a particular sensor over time can be compensated for by normalizing sensor readings to a maximum sensor reading at 1,000 mg/m{sup 3} TCE. The soil TCE screening method was expanded to include application to water samples. Assuming complete vaporization, the detection limit for TCE in soil is about 1 ug/kg (ppb) for a 25-g sample in an 8-oz jar. The detection limit for TCE in water is about 1 ug/L (ppb) for a 25-mL sample in an 8-oz jar. This is comparable to quantitation limits of EPA GC/MS laboratory methods. A draft ASTM method for screening TCE contaminated soils using a heated diode sensor was successfully submitted for concurrent main committee and subcommittee balloting in ASTM Committee D 34 on Waste Management. The method was approved as ASTM D 7203-05, Standard Test Method for Screening Trichloroethylene (TCE)-Contaminated Soil Using a Heated Diode Sensor.

John F. Schabron; Susan S. Sorini; Joseph F. Rovani Jr

2006-03-01T23:59:59.000Z

136

Microscopic and self-consistent description for neutron halo in deformed nuclei  

SciTech Connect

A deformed relativistic Hartree-Bogoliubov theory in continuum has been developed for the study of neutron halos in deformed nuclei and the halo phenomenon in deformed weakly bound nuclei is investigated. Magnesium and neon isotopes are studied and some results are presented for the deformed neutron-rich and weakly bound nuclei {sup 44}Mg and {sup 36}Ne. The core of the former nucleus is prolate, but the halo has a slightly oblate shape. This indicates a decoupling of the halo orbitals from the deformation of the core. The generic conditions for the existence of halos in deformed nuclei and for the occurrence of this decoupling effect are discussed.

Li Lulu [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); Meng Jie [State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China) and Department of Physics, University of Stellenbosch, Stellenbosch (South Africa); Zhao Enguang; Zhou Shangui [State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190 (China) and Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000 (China)

2013-05-06T23:59:59.000Z

137

Instructions for Corning Model 220 pH Meter The electrode tip is a fragile glass bulb. Be careful or you will break it with a  

E-Print Network (OSTI)

Instructions for Corning Model 220 pH Meter The electrode tip is a fragile glass bulb. Be careful. Two Point Calibration Routine · The pH meter should be turned "ON". · Your buffers should from your sample, rinse with distilled water, and BLOT with a kimwipe. 4. Turn pH meter OFF and store

Cross, George

138

Characterization of Disruption Halo Currents in the National Spherical Torus Experiment  

SciTech Connect

This paper describes the general characteristics of disruptions halo currents in the National Spherical Torus Experiment [M. Ono, et al. Nuclear Fusion 40, 557 (2000)]. The commonly observed types of vertical motion and resulting halo current patterns are described, and it is shown that plasma discharges developing between components can facilitate halo current flow. The halo current fractions and toroidal peaking factors at various locations in the device are presented. The maximum product of these two metrics for localized halo current measurements is always significantly less than the worst-case expectations from conventional aspect ratio tokamaks (which are typically written in terms of the total halo current). The halo current fraction and impulse is often largest in cases with the fastest plasma current quenches and highest quench rates. The effective duration of the halo current pulse is comparable to or shorter than the plasma current quench time. The largest halo currents have tended to occur in lower ? and lower elongation plasmas. The sign of the poloidal halo current is reversed when the toroidal field direction is reversed.

S.P. Gerhardt, J. Menard, S. Sabbagh and F. Scotti

2012-04-25T23:59:59.000Z

139

Neutron structure effects in the deuteron and one neutron halos  

E-Print Network (OSTI)

Although the neutron (n) does not carry a total electric charge, its charge and magnetization distributions represented in momentum space by the electromagnetic form factors, $F_1^{(n)} (q^2)$ and $F_2^{(n)} (q^2)$, lead to an electromagnetic potential of the neutron. Using this fact, we calculate the electromagnetic corrections to the binding energy, $B_d$, of the deuteron and a one neutron halo nucleus (11Be), by evaluating the neutron-proton and the neutron-charged core (10Be) potential, respectively. The correction to $B_d$ (~9 keV) is comparable to that arising due to the inclusion of the $\\Delta$-isobar component in the deuteron wave function. In the case of the more loosely bound halo nucleus, 11Be, the correction is close to about 2 keV.

M. Nowakowski; N. G. Kelkar; T. Mart

2005-11-28T23:59:59.000Z

140

Neutron structure effects in the deuteron and one neutron halos  

Science Journals Connector (OSTI)

Although the neutron (n) does not carry a total electric charge, its charge and magnetization distributions represented in momentum space by the electromagnetic form factors, F1(n)(q2) and F2(n)(q2), lead to an electromagnetic potential of the neutron. Using this fact, we calculate the electromagnetic corrections to the binding energy, Bd, of the deuteron and a one-neutron halo nucleus (Be11) by evaluating the neutron-proton and the neutron-charged core (Be10) potential, respectively. The correction to Bd (?9 keV) is comparable to that arising due to the inclusion of the ?-isobar component in the deuteron wave function. In the case of the more loosely bound halo nucleus, Be11, the correction is close to about 2 keV.

M. Nowakowski; N. G. Kelkar; T. Mart

2006-08-28T23:59:59.000Z

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141

The "Super-Halo" of M31 and M33  

E-Print Network (OSTI)

Two recent observations regarding the halo of M33 seem to contradict each other. First, the star clusters in the halo of M33 exhibit an age range of 5 to 7 Gyr suggesting a formation scenario that involves the chaotic fragmentation and accretion of dwarf satellites. In contrast, deep photometric searches for the resultant tidal tails and stellar streams in the vicinity of M33 have turned up nothing significant. In this contribution, we have tried to reconcile these apparently disparate observations. We suggest that M33 is situated within a 'superhalo' which contains many other dwarf spheroidal and dwarf irregular galaxies that are satellites of M31. In such a scenario, the tidal field of M31 could have disrupted and/or diluted the leftover tails and streams leaving little to be detected in the present day.

Ata Sarajedini

2006-10-20T23:59:59.000Z

142

Rotation curves of rotating galactic BEC dark matter halos  

E-Print Network (OSTI)

We present the dynamics of rotating Bose Condensate galactic dark matter halos, made of an ultralight spinless boson. We restrict to the case of adding axisymmetric rigid rotation to initially spherically symmetric structures and show there are three regimes: i) small angular momentum, that basically retains the drawbacks of spherically symmetric halos related to compactness and failure at explaining galactic RCs, ii) an intermediate range of values of angular momentum that allow the existence of long-lived structures with acceptable RC profiles, and iii) high angular momentum, in which the structure is dispersed away by rotation. We also present in detail the new code used to solve the Gross-Pitaevskii Poisson system of equations in three dimensions.

F. S. Guzman; F. D. Lora-Clavijo; J. J. Gonzalez-Aviles; F. J. Rivera-Paleo

2013-10-15T23:59:59.000Z

143

ON THE HOT GAS CONTENT OF THE MILKY WAY HALO  

SciTech Connect

The Milky Way appears to be missing baryons, as the observed mass in stars and gas is well below the cosmic mean. One possibility is that a substantial fraction of the Galaxy's baryons are embedded within an extended, million-degree hot halo, an idea supported indirectly by observations of warm gas clouds in the halo and gas-free dwarf spheroidal satellites. X-ray observations have established that hot gas does exist in our Galaxy beyond the local hot bubble; however, it may be distributed in a hot disk configuration. Moreover, recent investigations into the X-ray constraints have suggested that any Galactic corona must be insignificant. Here we re-examine the observational data, particularly in the X-ray and radio bands, in order to determine whether it is possible for a substantial fraction of the Galaxy's baryons to exist in {approx}10{sup 6} K gas. In agreement with past studies, we find that a baryonically closed halo is clearly ruled out if one assumes that the hot corona is distributed with a cuspy Navarro-Frenk-White profile. However, if the hot corona of the galaxy is in an extended, low-density distribution with a large central core, as expected for an adiabatic gas in hydrostatic equilibrium, then it may contain up to 10{sup 11} M {sub Sun} of material, possibly accounting for all of the missing Galactic baryons. We briefly discuss some potential avenues for discriminating between a massive, extended hot halo and a local hot disk.

Fang, Taotao [Department of Astronomy and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen, Fujian 361005 (China)] [Department of Astronomy and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen, Fujian 361005 (China); Bullock, James; Boylan-Kolchin, Michael [Department of Physics and Astronomy, 4129 Frederick Reines Hall, University of California, Irvine, CA 92697 (United States)] [Department of Physics and Astronomy, 4129 Frederick Reines Hall, University of California, Irvine, CA 92697 (United States)

2013-01-01T23:59:59.000Z

144

The Dark Matter halo of the Milky Way, AD 2013  

SciTech Connect

We derive the mass model of the Milky Way (MW), crucial for Dark Matter (DM) direct and indirect detection, using recent data and a cored dark matter (DM) halo profile, which is favoured by studies of external galaxies. The method used consists in fitting a spherically symmetric model of the Galaxy with a Burkert DM halo profile to available data: MW terminal velocities in the region inside the solar circle, circular velocity as recently estimated from maser star forming regions at intermediate radii, and velocity dispersions of stellar halo tracers for the outermost Galactic region. The latter are reproduced by integrating the Jeans equation for every modeled mass distribution, and by allowing for different velocity anisotropies for different tracer populations. For comparison we also consider a Navarro-Frenk-White profile. We find that the cored profile is the preferred one, with a shallow central density of ?{sub H} ? 4 × 10{sup 7}M{sub ?}/kpc{sup 3} and a large core radius R{sub H} ? 10 kpc, as observed in external spirals and in agreement with the mass model underlying the Universal Rotation Curve of spirals. We describe also the derived model uncertainties, which are crucially driven by the poorly constrained velocity dispersion anisotropies of halo tracers. The emerging cored DM distribution has implications for the DM annihilation angular profile, which is much less boosted in the Galactic center direction with respect to the case of the standard ?CDM, NFW profile. Using the derived uncertainties we discuss finally the limitations and prospects to discriminate between cored and cusped DM profile with a possible observed diffuse DM annihilation signal. The present mass model aims to characterize the present-day description of the distribution of matter in our Galaxy, which is needed to frame current crucial issues of Cosmology, Astrophysics and Elementary Particles.

Nesti, Fabrizio [Gran Sasso Science Institute, viale Crispi 7, I-67100 L'Aquila (Italy); Salucci, Paolo, E-mail: nesti@aquila.infn.it, E-mail: salucci@sissa.it [Scuola Internazionale Superiore di Studi Avanzati (SISSA/ISAS), Via Bonomea 265, I-34136 Trieste (Italy)

2013-07-01T23:59:59.000Z

145

Biomarker sensitivity for polynuclear and halogenated aromatic hydrocarbon contamination in fish species from Galveston Bay  

SciTech Connect

The Galveston Bay estuary exhibits a contamination gradient for polynuclear aromatic hydrocarbons (PAHs) and halogenated aromatic hydrocarbons, which is useful for comparing biomarker response sensitivity in fish taken from different bay locations. Two fish species, hardhead catfish (Arius felis) and Atlantic croaker (Micropogon undulatus), were collected from four stations where sediment total PAHs ranged from 68 to > 1,000 ng/g. Hardhead catfish showed no consistent CYP1A mediated responses (hepatic ethoxyresorufin-O-deethylase activity (EROD), CYP1A mRNA levels, or CYP1A immunoreactive protein) in the field collected fish or in fish dosed with up to 15 mg/kg benzo(a)pyrene (BaP). Significant differences were seen in field collected hardhead catfish in biliary concentrations of naphthalene, phenanthrene, and BaP metabolites. Conversely, in croakers taken from the same four Galveston Bay locations, there were significant elevations IN EROD and glutathione-S-transferase activities, CYP1A immunoreactive protein, and biliary PAH metabolites at the contaminated stations. These studies suggest that croaker is a good monitoring species especially with respect to induction of CYP1A mediated responses by PAHs. Biliary PAH metabolites and PAH-DNA adducts were sensitive to PAH contamination in both species.

Willett, K.; McDonald, S.; Steinberg, M.; Beatty, K.; Safe, S. [Texas A and M Univ., College Station, TX (United States)

1995-12-31T23:59:59.000Z

146

Neutron-Neutron Correlations in the Dissociation of Halo Nuclei  

E-Print Network (OSTI)

Studies attempting to probe the spatial configuration of the valence neutrons in two-neutron halo nuclei using the technique of intensity interferometry are described. Following a brief review of the method and its application to earlier measurements of the breakup of 6He, 11Li and 14Be, the results of the analysis of a high statistics data set for 6He are presented. The limitations of the technique, including the assumption of incoherent emission in the breakup and the sensitivity to the continuum states populated in the dissociation rather than the ground state, are discussed.

N. A. Orr

2008-03-06T23:59:59.000Z

147

Cosmic Ray Acceleration beyond the Knee up to the Ankle in the Galactic Wind Halo  

E-Print Network (OSTI)

Cosmic Ray Acceleration beyond the Knee up to the Ankle in the Galactic Wind Halo Vladimir Acceleration beyond the Knee up to the Ankle in the Galactic Wind Halo2 radius 100 kpc in this model. This size mechanism to produce the observed CRs beyond the so-called knee at several Ã?1015 eV to the so-called ankle

148

A measurement of galaxy halo mass from the surrounding H I Ly? absorption  

Science Journals Connector (OSTI)

......smaller minimum halo mass. Using a spectroscopic...for measuring halo mass is presented in Section...the 2D absorption maps from R12 in Section...II SNe, stellar winds, and asymptotic...The assumed initial mass function (IMF...particles are kicked at a velocity of 600s1. The mass......

Olivera Rakic; Joop Schaye; Charles C. Steidel; C. M. Booth; Claudio Dalla Vecchia; Gwen C. Rudie

2013-01-01T23:59:59.000Z

149

Velocity and mass bias in the distribution of dark matter haloes  

Science Journals Connector (OSTI)

......and for k-h1 at z-=-0.7. We test analytic halo bias models against our simulation...MXXL simulation, it is interesting to test the validity of these models for halo masses...mass bias (Section-3.1). We then test a prescription for suppressing the shot......

Elise Jennings; Carlton M. Baugh; Dylan Hatt

2015-01-01T23:59:59.000Z

150

The Ice Cream Cone Model for Inversing Geometrical Properties of Halo Coronal Mass Ejections  

E-Print Network (OSTI)

the front half ellipse produced by the cone part when the angle of the central axis of the ice cream coneThe Ice Cream Cone Model for Inversing Geometrical Properties of Halo Coronal Mass Ejections Xue Pu recently that most of halo coronal mass ejections (CMEs) may be formed by an ice cream cone-like shell

Zhao, Xuepu

151

The Interaction of the Disk with the Halo MordecaiMark Mac Low 1  

E-Print Network (OSTI)

in the halo or even ejection of mass along open field lines in a galactic wind. In these models, the energy and energy to the halo, as well as opening up lines of sight for ionizing radiation to escape from the disk external sources could contribute). The most likely energy source for these processes are massive OB stars

Low, Mordecai-Mark Mac

152

EMPIRICAL MODELS FOR DARK MATTER HALOS. II. INNER PROFILE SLOPES, DYNAMICAL PROFILES, AND /3  

E-Print Network (OSTI)

simulated dark matter halos better than a Navarro- Frenk-WhiteYlike model with an equal number of parameters]) density profiles of simulated dark matter halos (Navarro et al. 2004). Intriguingly, this function was shown to provide a better fit than thethree-parameter Navarro-Frenk-White (NFW)Ylike model

Terzi, BalÂ?a

153

Separation of toxic metal ions, hydrophilic hydrocarbons, hydrophobic fuel and halogenated hydrocarbons and recovery of ethanol from a process stream  

DOE Patents (OSTI)

This invention provides a process to tremendously reduce the bulk volume of contaminants obtained from an effluent stream produced subsurface remediation. The chemicals used for the subsurface remediation are reclaimed for recycling to the remediation process. Additional reductions in contaminant bulk volume are achieved by the ultra-violet light destruction of halogenated hydrocarbons, and the complete oxidation of hydrophobic fuel hydrocarbons and hydrophilic hydrocarbons. The contaminated bulk volume will arise primarily from the disposal of the toxic metal ions. The entire process is modular, so if there are any technological breakthroughs in one or more of the component process modules, such modules can be readily replaced.

Kansa, Edward J. (Livermore, CA); Anderson, Brian L. (Lodi, CA); Wijesinghe, Ananda M. (Tracy, CA); Viani, Brian E. (Oakland, CA)

1999-01-01T23:59:59.000Z

154

THE SPIN AND ORIENTATION OF DARK MATTER HALOS WITHIN COSMIC FILAMENTS  

SciTech Connect

Clusters, filaments, sheets, and voids are the building blocks of the cosmic web. Forming dark matter halos respond to these different large-scale environments, and this in turn affects the properties of galaxies hosted by the halos. It is therefore important to understand the systematic correlations of halo properties with the morphology of the cosmic web, as this informs both about galaxy formation physics and possible systematics of weak lensing studies. In this study, we present and compare two distinct algorithms for finding cosmic filaments and sheets, a task which is far less well established than the identification of dark matter halos or voids. One method is based on the smoothed dark matter density field and the other uses the halo distributions directly. We apply both techniques to one high-resolution N-body simulation and reconstruct the filamentary/sheet like network of the dark matter density field. We focus on investigating the properties of the dark matter halos inside these structures, in particular, on the directions of their spins and the orientation of their shapes with respect to the directions of the filaments and sheets. We find that both the spin and the major axes of filament halos with masses approx<10{sup 13} h {sup -1} M{sub sun} are preferentially aligned with the direction of the filaments. The spins and major axes of halos in sheets tend to lie parallel to the sheets. There is an opposite mass dependence of the alignment strength for the spin (negative) and major (positive) axes, i.e. with increasing halo mass the major axis tends to be more strongly aligned with the direction of the filament, whereas the alignment between halo spin and filament becomes weaker with increasing halo mass. The alignment strength as a function of the distance to the most massive node halo indicates that there is a transit large-scale environment impact: from the two-dimensional collapse phase of the filament to the three-dimensional collapse phase of the cluster/node halo at small separation. Overall, the two algorithms for filament/sheet identification investigated here agree well with each other. The method based on halos alone can be easily adapted for use with observational data sets.

Zhang Youcai; Yang Xiaohu; Lin Weipeng [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Partner Group of MPA, Nandan Road 80, Shanghai 200030 (China); Faltenbacher, Andreas; Springel, Volker [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Strasse 1, 85748 Garching (Germany); Wang Huiyuan, E-mail: yczhang@shao.ac.c [Key Laboratory for Research in Galaxies and Cosmology, Center for Astrophysics, University of Science and Technology of China, 230026 (China)

2009-11-20T23:59:59.000Z

155

Decaying Dark Matter and the Deficit of Dwarf Haloes  

E-Print Network (OSTI)

The hierarchical clustering inherent in Lambda-CDM cosmology seems to produce many of the observed characteristics of large-scale structure. But some glaring problems still remain, including the over-prediction (by a factor 10) of the number of dwarf galaxies within the virialized population of the local group. Several secondary effects have already been proposed to resolve this problem. It is still not clear, however, whether the principal solution rests with astrophysical processes, such as early feedback from supernovae, or possibly with as yet undetermined properties of the dark matter itself. In this paper, we carry out a detailed calculation of the dwarf halo evolution incorporating the effects of a hypothesized dark-matter decay, D -> D'+l, where D is the unstable particle, D' is the more massive daughter particle and l is the other, lighter (or possibly massless) daughter particle. This process preferentially heats the smaller haloes, expanding them during their evolution and reducing their present-day circular velocity. We find that this mechanism can account very well for the factor 4 deficit in the observed number of systems with velocity 10--20 km/s compared to those predicted by the numerical simulations, if dm/m_D' ~ 5-7 x 10^{-5}, where dm is the mass difference between the initial and final states. The corresponding lifetime tau cannot be longer than ~30 Gyr, but may be as short as just a few Gyr.

Majd Abdelqader; Fulvio Melia

2008-06-03T23:59:59.000Z

156

Induced Nested Galactic Bars Inside Assembling Dark Matter Halos  

E-Print Network (OSTI)

We investigate the formation and evolution of nested bar systems in disk galaxies in a cosmological setting by following the development of an isolated dark matter (DM) and baryon density perturbation. The disks form within the assembling triaxial DM halos and the feedback from the stellar evolution is accounted for in terms of supernovae and OB stellar winds. Focusing on a representative model, we show the formation of an oval disk and of a first generation of nested bars with characteristic sub-kpc and a few kpc sizes. The system evolves through successive dynamical couplings and decouplings, forcing the gas inwards and settles in a state of resonant coupling. The inflow rate can support a broad range of activity within the central kpc, from quasar- to Seyfert-types, supplemented by a vigorous star formation as a by-product. The initial bar formation is triggered in response to the tidal torques from the triaxial DM halo, which acts as a finite perturbation. This first generation of bars does not survive for more than 4--5 Gyr: by that time the secondary bar has totally dissolved, while the primary one has very substantially weakened, reduced to a fat oval. This evolution is largely due to chaos introduced by the interaction of the multiple non-axisymmetric components.

Clayton Heller; Isaac Shlosman; Lia Athanassoula

2007-06-26T23:59:59.000Z

157

CN ANOMALIES IN THE HALO SYSTEM AND THE ORIGIN OF GLOBULAR CLUSTERS IN THE MILKY WAY  

SciTech Connect

We explore the kinematics and orbital properties of a sample of red giants in the halo system of the Milky Way that are thought to have formed in globular clusters based on their anomalously strong UV/blue CN bands. The orbital parameters of the CN-strong halo stars are compared to those of the inner- and outer-halo populations as described by Carollo et al., and to the orbital parameters of globular clusters with well-studied Galactic orbits. The CN-strong field stars and the globular clusters both exhibit kinematics and orbital properties similar to the inner-halo population, indicating that stripped or destroyed globular clusters could be a significant source of inner-halo field stars, and suggesting that both the CN-strong stars and the majority of globular clusters are primarily associated with this population.

Carollo, Daniela [Department of Physics and Astronomy-Astronomy, Astrophysics and Astrophotonic Research Center Macquarie University-North Ryde, 2109 NSW (Australia); Martell, Sarah L. [Australian Astronomical Observatory, North Ryde, 2109 NSW (Australia); Beers, Timothy C. [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States); Freeman, Ken C., E-mail: daniela.carollo@mq.edu.au, E-mail: smartell@aao.gov.au, E-mail: beers@noao.edu, E-mail: kcf@mso.anu.edu.au [Research School of Astronomy and Astrophysics, Australian National University and Mount Stromlo Observatory, Cotter Road, Weston, ACT 2611 (Australia)

2013-06-01T23:59:59.000Z

158

Information content in the halo-model dark-matter power spectrum  

E-Print Network (OSTI)

Using the halo model, we investigate the cosmological Fisher information in the non-linear dark-matter power spectrum about the initial amplitude of linear power. We find that there is little information on `translinear' scales (where the one- and two-halo terms are both significant) beyond what is on linear scales, but that additional information is present on small scales, where the one-halo term dominates. This behavior agrees with the surprising results that Rimes & Hamilton (2005, 2006) found using N-body simulations. We argue that the translinear plateau in cumulative information arises largely from fluctuations in the numbers of large haloes in a finite volume. This implies that more information could be extracted on non-linear scales if the masses of the largest haloes in a survey are known.

Mark C. Neyrinck; István Szapudi; Christopher D. Rimes

2006-04-13T23:59:59.000Z

159

On the Formation of Galaxy Halos: Comparing NGC 5128 and the Local Group Members  

E-Print Network (OSTI)

The metallicity distribution function (MDF) for the old red-giant stars in the halo of NGC 5128, the nearest giant elliptical galaxy, is virtually identical with the MDF for the old-disk stars in the LMC and also strongly resembles the halo MDF in M31. These galaxies all have high mean halo metallicities ( ~ -0.4$) with very small proportions of low-metallicity stars. These observations reinforce the view that metal-rich halos are quite normal for large galaxies of all types. Such systems are unlikely to have built up by accretion of pre-existing, gas-free small satellite galaxies, unless these satellites had an extremely shallow mass distribution (d log N / d log M > -1). We suggest that the halo of NGC 5128 is more likely to have assembled from hierarchical merging of gas-rich lumps in which the bulk of star formation took place during or after the merger stage.

W. E. Harris; G. L. H. Harris

2001-08-14T23:59:59.000Z

160

Quantitative structure–activity relationships for toxicity and genotoxicity of halogenated aliphatic compounds: Wing spot test of Drosophila melanogaster  

Science Journals Connector (OSTI)

Halogenated aliphatic compounds were evaluated for toxic and genotoxic effects in the somatic mutation and recombination test employing Drosophila melanogaster. The tested chemicals included chlorinated, brominated and iodinated; mono-, di- and tri-substituted; saturated and unsaturated alkanes: 1,2-dibromoethane, 1-bromo-2-chloroethane, 1-iodopropane, 2,3-dichloropropene, 3-bromo-1-propene, epibromohydrin, 2-iodobutane, 3-chloro-2-methylpropene, 1,2,3-trichloropropane, 1,2-dichloroethane, 1,2-dichlorobutane, 1-chloro-2-methylpropane, 1,3-dichloropropane, 1,2-dichloropropane, 2-chloroethymethylether, 1-bromo-2-methylpropane and 1-chloropentane. N-methyl-N-nitrosourea served as the positive and distilled water as the negative control. The set of chemicals for the toxicological testing was selected by the use of statistical experiment design. Group of unsaturated aliphatic hydrocarbons were generally more toxic than saturated analogues. The genotoxic effect was observed with 14 compounds in the wing spot test, while 3 substances did not show any genotoxicity by using the wing spot test at 50% lethal concentration. The highest number of wing spots was observed in genotoxicity assay with 1-bromo-2-chloroethane, 1,2-dichloroethane, 1,2-dibromoethane and 1-iodopropane. Nucleophilic superdelocalizability calculated by quantum mechanics appears to be a good parameter for prediction of both toxicity and genotoxicity effects of halogenated aliphatic compounds.

Karel Chroust; Martina Pavlová; Zbyn?k Prokop; Jan Mendel; Kate?ina Božková; Zden?k Kubát; Veronika Zaj?´?ková; Ji??´ Damborský

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Semi-empirical catalog of early-type galaxy-halo systems: dark matter density profiles, halo contraction and dark matter annihilation strength  

SciTech Connect

With Sloan Digital Sky Survey galaxy data and halo data from up-to-date N-body simulations within the ?CDM framework we construct a semi-empirical catalog (SEC) of early-type galaxy-halo systems by making a self-consistent bivariate statistical match of stellar mass (M{sub *}) and velocity dispersion (?) with halo virial mass (M{sub vir}) as demonstrated here for the first time. We then assign stellar mass profile and velocity dispersion profile parameters to each system in the SEC using their observed correlations with M{sub *} and ?. Simultaneously, we solve for dark matter density profile of each halo using the spherical Jeans equation. The resulting dark matter density profiles deviate in general from the dissipationless profile of Navarro-Frenk-White or Einasto and their mean inner density slope and concentration vary systematically with M{sub vir}. Statistical tests of the distribution of profiles at fixed M{sub vir} rule out the null hypothesis that it follows the distribution predicted by dissipationless N-body simulations for M{sub vir}?<10{sup 13.5} {sup –} {sup 14.5} M{sub s}un. These dark matter profiles imply that dark matter density is, on average, enhanced significantly in the inner region of halos with M{sub vir}?<10{sup 13.5} {sup –} {sup 14.5} M{sub s}un supporting halo contraction. The main characteristics of halo contraction are: (1) the mean dark matter density within the effective radius has increased by a factor varying systematically up to ? 3–4 at M{sub vir} = 10{sup 12} M{sub s}un, and (2) the inner density slope has a mean of (?) ? 1.3 with ?{sub dm}(r)?r{sup ??} and a halo-to-halo rms scatter of rms(?) ? 0.4–0.5 for 10{sup 12} M{sub s}un?halos of nearby elliptical and lenticular galaxies can, in principle, be promising targets for ?-ray emission from dark matter annihilation.

Chae, Kyu-Hyun [Department of Astronomy and Space Science, Sejong University, 98 Gunja-dong Gwangjin-Gu, Seoul 143-747 (Korea, Republic of); Kravtsov, Andrey V. [Kavli Institute for Cosmological Physics, The University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Frieman, Joshua A. [Center for Particle Astrophysics, Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States); Bernardi, Mariangela, E-mail: chae@sejong.ac.kr, E-mail: andrey@oddjob.uchicago.edu, E-mail: frieman@fnal.gov, E-mail: bernardm@physics.upenn.edu [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States)

2012-11-01T23:59:59.000Z

162

$^6$He nucleus in halo effective field theory  

E-Print Network (OSTI)

Background: In recent years properties of light rare isotopes have been measured with high accuracy. At the same time, the theoretical description of light nuclei has made enormous progress, and properties of, e.g., the Helium isotopes can now be calculated {\\it ab initio}. These advances make those rare isotopes an ideal testing ground for effective field theories (EFTs) built upon cluster degrees of freedom. Purpose: Systems with widely separated intrinsic scales are well suited to an EFT treatment. The Borromean halo nucleus $^6$He exhibits such a separation of scales. In this work an EFT in which the degrees of freedom are the valence neutrons ($n$) and an inert $^4$He-core ($\\alpha$) is employed. The properties of ${}^6$He can then be calculated using the momentum-space Faddeev equations for the $\\alpha nn$ bound state to obtain information on ${}^6$He at leading order (LO) within the EFT. Results: The $nn$ virtual state and the $^2$P$_{3/2}$ resonance in $^5$He give the two-body amplitudes which are input to our LO three-body Halo EFT calculation. We find that without a genuine three-body interaction the two-neutron separation energy $S_{2n}$ of ${}^6$He is strongly cutoff dependent. We introduce a $nn \\alpha$ "three-body" operator which renormalizes the system, adjusting its coefficient to reproduce the $S_{2n}$ of $^6$He. The Faddeev components are then cutoff independent for cutoffs of the order of, and above, the breakdown scale of the Halo EFT. Conclusions: As in the case of a three-body system where only resonant s-wave interactions are present, one three-body input is required for the renormalization of the EFT equations that describe $^6$He at LO. However, in contrast to the s-wave-only case, the running of the LO $nn\\alpha$ counterterm does not exhibit discrete scale invariance, due to the presence of the p-wave $n\\alpha$ interaction.

C. Ji; Ch. Elster; D. R. Phillips

2014-11-03T23:59:59.000Z

163

DARK MATTER HALO PROFILES OF MASSIVE CLUSTERS: THEORY VERSUS OBSERVATIONS  

SciTech Connect

Dark-matter-dominated cluster-scale halos act as an important cosmological probe and provide a key testing ground for structure formation theory. Focusing on their mass profiles, we have carried out (gravity-only) simulations of the concordance {Lambda}CDM cosmology, covering a mass range of 2 Multiplication-Sign 10{sup 12} to 2 Multiplication-Sign 10{sup 15} h {sup -1} M{sub Sun} and a redshift range of z = 0-2, while satisfying the associated requirements of resolution and statistical control. When fitting to the Navarro-Frenk-White profile, our concentration-mass (c-M) relation differs in normalization and shape in comparison to previous studies that have limited statistics in the upper end of the mass range. We show that the flattening of the c-M relation with redshift is naturally expressed if c is viewed as a function of the peak height parameter, {nu}. Unlike the c-M relation, the slope of the c-{nu} relation is effectively constant over the redshift range z = 0-2, while the amplitude varies by {approx}30% for massive clusters. This relation is, however, not universal: using a simulation suite covering the allowed wCDM parameter space, we show that the c-{nu} relation varies by about {+-}20% as cosmological parameters are varied. At fixed mass, the c(M) distribution is well fit by a Gaussian with {sigma}{sub c}/(c) {approx_equal} 1/3, independent of the radius at which the concentration is defined, the halo dynamical state, and the underlying cosmology. We compare the {Lambda}CDM predictions with observations of halo concentrations from strong lensing, weak lensing, galaxy kinematics, and X-ray data, finding good agreement for massive clusters (M{sub vir} > 4 Multiplication-Sign 10{sup 14} h {sup -1} M{sub Sun }), but with some disagreements at lower masses. Because of uncertainty in observational systematics and modeling of baryonic physics, the significance of these discrepancies remains unclear.

Bhattacharya, Suman; Habib, Salman; Heitmann, Katrin [High Energy Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States)] [High Energy Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Vikhlinin, Alexey [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)] [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

2013-03-20T23:59:59.000Z

164

Untitled  

U.S. Energy Information Administration (EIA) Indexed Site

9. Number of Lights by Type of Bulb by Hours Used, 1993 Bulb Type Incandescent Fluorescent Other Hours Used Total Low Medium High Unknown Short Long Compact Halogen Other Unknown...

165

Internal Alignments of Red Versus Blue Discs in Dark Matter Halos  

E-Print Network (OSTI)

Large surveys have shown that red galaxies are preferentially aligned with their halos while blue galaxies have a more isotropic distribution. Since halos generally align with their filaments this introduces a bias in the measurement of the cosmic shear from weak lensing. It is therefore vitally important to understand why this difference arises. We explore the stability of different disc orientations within triaxial halos. We show that, in the absence of gas, the disc orientation is most stable when its spin is along the minor axis of the halo. Instead when gas cools onto a disc it is able to form in almost arbitrary orientation, including off the main planes of the halo (but avoiding an orientation perpendicular to the halo's intermediate axis). Substructure helps gasless galaxies reach alignment with the halo faster, but have less effect on galaxies when gas is cooling onto the disc. Our results provide a novel and natural interpretation for why red, gas poor galaxies are preferentially aligned with their ...

Debattista, Victor P; Roskar, Rok; Quinn, Thomas; Moore, Ben; Cole, David R

2015-01-01T23:59:59.000Z

166

The results of deep CCD field surveys: Very low mass halo population stars as dark matter  

Science Journals Connector (OSTI)

Halo and disk M dwarfs differ significantly in metallicity. Multi?color deep CCD surveys are uniquely capable of detecting these separate populations of stars with differing metallicity and therefore colors. Analyzing very deep three?band CCD images covering 192 arcmin2 at high galactic latitude we find no evidence for a population of extreme low mass M subdwarfs sufficient to account for the halo dark matter. These observations covering a volume of 2×105 pc3 are consistent with extrapolations of a halo luminosity function determined using low metallicity stars in the solar neighborhood.

P. C. Boeshaar; J. A. Tyson; G. M. Bernstein

1995-01-01T23:59:59.000Z

167

Water molecules insert into N-HCl-M hydrogen bonds while M-ClX-C halogen bonds remain intact in dihydrates of halopyridinium hexachloroplatinates  

Science Journals Connector (OSTI)

Crystals of the dihydrates of three halopyridinium hexachloroplatinate salts form networks that are propagated via N-HO and O-HCl-Pt hydrogen bonds and Pt-ClX-C halogen bonds. The water molecules can be considered to have been inserted into N-HCl-Pt hydrogen bonds anticipated in the anyhdrous form of such salts.

Zordan, F.

2004-09-15T23:59:59.000Z

168

INVESTIGATION OF THE TOTAL ORGANIC HALOGEN ANALYTICAL METHOD AT THE WASTE SAMPLING AND CHARACTERIZATION FACILITY  

SciTech Connect

Total organic halogen (TOX) is used as a parameter to screen groundwater samples at the Hanford Site. Trending is done for each groundwater well, and changes in TOX and other screening parameters can lead to costly changes in the monitoring protocol. The Waste Sampling and Characterization Facility (WSCF) analyzes groundwater samples for TOX using the United States Environmental Protection Agency (EPA) SW-S46 method 9020B (EPA 1996a). Samples from the Soil and Groundwater Remediation Project (SGRP) are submitted to the WSCF for analysis without information regarding the source of the sample; each sample is in essence a ''blind'' sample to the laboratory. Feedback from the SGRP indicated that some of the WSCF-generated TOX data from groundwater wells had a number of outlier values based on the historical trends (Anastos 200Sa). Additionally, analysts at WSCF observed inconsistent TOX results among field sample replicates. Therefore, the WSCF lab performed an investigation of the TOX analysis to determine the cause of the outlier data points. Two causes were found that contributed to generating out-of-trend TOX data: (1) The presence of inorganic chloride in the groundwater samples: at inorganic chloride concentrations greater than about 10 parts per million (ppm), apparent TOX values increase with increasing chloride concentration. A parallel observation is the increase in apparent breakthrough of TOX from the first to the second activated-carbon adsorption tubes with increasing inorganic chloride concentration. (2) During the sample preparation step, excessive purging of the adsorption tubes with oxygen pressurization gas after sample loading may cause channeling in the activated carbon bed. This channeling leads to poor removal of inorganic chloride during the subsequent wash step with aqueous potassium nitrate. The presence of this residual inorganic chloride then produces erroneously high TOX values. Changes in sample preparation were studied to more effectively remove inorganic chloride from the activated-carbon adsorption tubes. With the TOX sample preparation equipment and TOX analyzers at WSCF, the nitrate wash recommended by EPA SW-846 method 9020B was found to be inadequate to remove inorganic chloride interference. Increasing the nitrate wash concentration from 10 grams per liter (g/L) to 100 giL potassium nitrate and increasing the nitrate wash volume from 3 milliliters (mL) to 10 mL effectively removed the inorganic chloride up to at least 100 ppm chloride in the sample matrix. Excessive purging of the adsorption tubes during sample preparation was eliminated. These changes in sample preparation have been incorporated in the analytical procedure. The results using the revised sample preparation procedure show better agreement of TOX values both for replicate analyses of single samples and for the analysis of replicate samples acquired from the same groundwater well. Furthermore, less apparent adsorption tube breakthrough now occurs with the revised procedure. One additional modification made to sample preparation was to discontinue the treatment of groundwater samples with sodium bisulfite. Sodium bisulfite is used to remove inorganic chlorine from the sample; inorganic chlorine is not expected to be a constituent in these groundwater samples. Several other factors were also investigated as possible sources of anomalous TOX results: (1) Instrument instability: examination of the history of results for TOX laboratory control samples and initial calibration verification standards indicate good long-term precision for the method and instrument. Determination of a method detection limit of 2.3 ppb in a deionized water matrix indicates the method and instrumentation have good stability and repeatability. (2) Non-linear instrument response: the instrument is shown to have good linear response from zero to 200 parts per billion (ppb) TOX. This concentration range encompasses the majority of samples received at WSCF for TOX analysis. Linear response was checked using both non-volatile TOX species (trichlorophenol) an

JG DOUGLAS; HK MEZNARICH, PHD; JR OLSEN; GA ROSS PHD; M STAUFFER

2009-02-13T23:59:59.000Z

169

INVESTIGATION OF THE TOTAL ORGANIC HALOGEN ANALYTICAL METHOD AT THE WASTE SAMPLING CHARACTERIZATION FACILITY (WSCF)  

SciTech Connect

Total organic halogen (TOX) is used as a parameter to screen groundwater samples at the Hanford Site. Trending is done for each groundwater well, and changes in TOX and other screening parameters can lead to costly changes in the monitoring protocol. The Waste Sampling and Characterization Facility (WSCF) analyzes groundwater samples for TOX using the United States Environmental Protection Agency (EPA) SW-846 method 9020B (EPA 1996a). Samples from the Soil and Groundwater Remediation Project (S&GRP) are submitted to the WSCF for analysis without information regarding the source of the sample; each sample is in essence a 'blind' sample to the laboratory. Feedback from the S&GRP indicated that some of the WSCF-generated TOX data from groundwater wells had a number of outlier values based on the historical trends (Anastos 2008a). Additionally, analysts at WSCF observed inconsistent TOX results among field sample replicates. Therefore, the WSCF lab performed an investigation of the TOX analysis to determine the cause of the outlier data points. Two causes were found that contributed to generating out-of-trend TOX data: (1) The presence of inorganic chloride in the groundwater samples: at inorganic chloride concentrations greater than about 10 parts per million (ppm), apparent TOX values increase with increasing chloride concentration. A parallel observation is the increase in apparent breakthrough of TOX from the first to the second activated-carbon adsorption tubes with increasing inorganic chloride concentration. (2) During the sample preparation step, excessive purging of the adsorption tubes with oxygen pressurization gas after sample loading may cause channeling in the activated-carbon bed. This channeling leads to poor removal of inorganic chloride during the subsequent wash step with aqueous potassium nitrate. The presence of this residual inorganic chloride then produces erroneously high TOX values. Changes in sample preparation were studied to more effectively remove inorganic chloride from the activated carbon adsorption tubes. With the TOX sample preparation equipment and TOX analyzers at WSCF, the nitrate wash recommended by EPA SW-846 method 9020B was found to be inadequate to remove inorganic chloride interference. Increasing the nitrate wash concentration from 10 grams per liter (g/L) to 100 g/L potassium nitrate and increasing the nitrate wash volume from 3 milliliters (mL) to 10 mL effectively removed the inorganic chloride up to at least 100 ppm chloride in the sample matrix. Excessive purging of the adsorption tubes during sample preparation was eliminated. These changes in sample preparation have been incorporated in the analytical procedure. The results using the revised sample preparation procedure show better agreement of TOX values both for replicate analyses of single samples and for the analysis of replicate samples acquired from the same groundwater well. Furthermore, less apparent column breakthrough now occurs with the revised procedure. One additional modification made to sample preparation was to discontinue the treatment of groundwater samples with sodium bisulfite. Sodium bisulfite is used to remove inorganic chlorine from the sample; inorganic chlorine is not expected to be a constituent in these groundwater samples. Several other factors were also investigated as possible sources of anomalous TOX results: (1) Instrument instability: examination of the history of results for TOX laboratory control samples and initial calibration verification standards indicate good long-term precision for the method and instrument. Determination of a method detection limit of 2.3 ppb in a deionized water matrix indicates the method and instrumentation have good stability and repeatability. (2) Non-linear instrument response: the instrument is shown to have good linear response from zero to 200 parts per billion (ppb) TOX. This concentration range encompasses the majority of samples received at WSCF for TOX analysis. (3) Improper sample preservation: ion-chromatographic analysis of several samples wit

DOUGLAS JG; MEZNARICH HD, PHD; OLSEN JR; ROSS GA; STAUFFER M

2008-09-30T23:59:59.000Z

170

Comparing Light Bulbs  

Energy.gov (U.S. Department of Energy (DOE))

In this exercise, students will use a light to demonstrate the difference between being energy-efficient and energy-wasteful, and learn what energy efficiency means.

171

Impacts of halogen additions on mercury oxidation, in a slipstream selective catalyst reduction (SCR), reactor when burning sub-bituminous coal  

SciTech Connect

This paper presents a comparison of impacts of halogen species on the elemental mercury (Hg(0)) oxidation in a real coal-derived flue gas atmosphere. It is reported there is a higher percentage of Hg(0) in the flue gas when burning sub-bituminous coal (herein Powder River Basin (PRB) coal) and lignite, even with the use of selective catalytic reduction (SCR). The higher Hg(0) concentration in the flue gas makes it difficult to use the wet-FGD process for the mercury emission control in coal-fired utility boilers. Investigation of enhanced Hg(0) oxidation by addition of hydrogen halogens (HF, HCl, HBr, and HI) was conducted in a slipstream reactor with and without SCR catalysts when burning PRB coal. Two commercial SCR catalysts were evaluated. SCR catalyst no. 1 showed higher efficiencies of both NO reduction and Hg(0) oxidation than those of SCR catalyst no. 2. NH{sub 3} addition seemed to inhibit the Hg(0) oxidation, which indicated competitive processes between NH{sub 3} reduction and Hg(0) oxidation on the surface of SCR catalysts. The hydrogen halogens, in the order of impact on Hg(0) oxidation, were HBr, HI, and HCl or HF. Addition of HBr at approximately 3 ppm could achieve 80% Hg(0) oxidation. Addition of HI at approximately 5 ppm could achieve 40% Hg(0) oxidation. In comparison to the empty reactor, 40% Hg(0) oxidation could be achieved when HCl addition was up to 300 ppm. The enhanced Hg(0) oxidation by addition of HBr and HI seemed not to be correlated to the catalytic effects by both evaluated SCR catalysts. The effectiveness of conversion of hydrogen halogens to halogen molecules or interhalogens seemed to be attributed to their impacts on Hg(0) oxidation. 30 refs., 4 figs.

Yan Cao; Zhengyang Gao; Jiashun Zhu; Quanhai Wang; Yaji Huang; Chengchung Chiu; Bruce Parker; Paul Chu; Wei-ping Pan [Western Kentucky University (WKU), Bowling Green, KY (United States). Institute for Combustion Science and Environmental Technology (ICSET)

2008-01-01T23:59:59.000Z

172

The Halo Formation Rate and its link to the Global Star Formation Rate  

E-Print Network (OSTI)

The star formation history of the universe shows strong evolution with cosmological epoch. Although we know mergers between galaxies can cause luminous bursts of star formation, the relative importance of such mergers to the global star formation rate (SFR) is unknown. We present a simple analytic formula for the rate at which halos merge to form higher-mass systems, derived from Press-Schechter theory and confirmed by numerical simulations (for high halo masses). A comparison of the evolution in halo formation rate with the observed evolution in the global SFR indicates that the latter is largely driven by halo mergers at z>1. Recent numerical simulations by Kolatt et al. (1999) and Knebe & Muller (1999) show how merging systems are strongly biased tracers of mass fluctuations, thereby explaining the strong clustering observed for Lyman-break galaxies without any need to assume that Lyman-break galaxies are associated only with the most massive systems at z~3.

W. J. Percival; L. Miller; W. E. Ballinger

1999-09-15T23:59:59.000Z

173

Halo Mergers, Galaxy Mergers, and Why Hubble Type Depends on Mass  

E-Print Network (OSTI)

In the CDM cosmological framework structures grow from merging with smaller structures. Merging should have observable effects on galaxies including destroying disks and creating spheroids. This proceeding aims to give a brief overview of how mergers occur in cosmological simulations. In this regard it is important to understand that dark matter halo mergers are not galaxy mergers; a theory of galaxy formation is necessary to connect the two. Mergers of galaxies in hydrodynamical simulations show a stronger dependence on mass than halo mergers in N-body simulations. If one knows how to connect galaxies to dark matter halos then the halo merger rate can be converted into a galaxy merger rate. When this is done it becomes clear that major mergers are many times more common in more massive galaxies offering a possible explanation of why Hubble type depends on galaxy mass.

Ariyeh H. Maller

2008-01-29T23:59:59.000Z

174

Axial Ratio of Edge-On Spiral Galaxies as a Test For Extended Bright Radio Halos  

E-Print Network (OSTI)

We use surface brightness contour maps of nearby edge-on spiral galaxies to determine whether extended bright radio halos are common. In particular, we test a recent model of the spatial structure of the diffuse radio continuum by Subrahmanyan and Cowsik which posits that a substantial fraction of the observed high-latitude surface brightness originates from an extended Galactic halo of uniform emissivity. Measurements of the axial ratio of emission contours within a sample of normal spiral galaxies at 1500 MHz and below show no evidence for such a bright, extended radio halo. Either the Galaxy is atypical compared to nearby quiescent spirals or the bulk of the observed high-latitude emission does not originate from this type of extended halo.

Singal, J; Jones, E; Dunlap, H

2015-01-01T23:59:59.000Z

175

Limits on Hot Galactic Halo Gas from X-ray Absorption Lines  

E-Print Network (OSTI)

Although the existence of large-scale hot gaseous halos around massive disk galaxies has been theorized for a long time, there is yet very little observational evidence. We report the Chandra and XMM-Newton grating spectral ...

Yao, Yangsen

176

The effect of spin-orbit splitting on the association kinetics of barrierless halogen atom-hydrocarbon radical reactions.  

SciTech Connect

The effect of the geometry dependence of spin-orbit splitting on transition state theory (TST) predictions for radical-radical recombination rate coefficients is examined. The effects are illustrated with direct ab initio variable-reaction-coordinate (VRC)-TST calculations for the reactions of two types of hydrocarbon radicals (R = CH{sub 3} and CH{sub 2}CHCH{sub 2}) with three halogen atoms (X = F, Cl, and Br). These halogen atoms exhibit a range of spin-orbit interaction strengths, while their interactions with the two hydrocarbon radicals exhibit a range of attractiveness. The transition state dividing surfaces for these barrierless reactions occur over a range of R-X fragment separations ({approx}3-7 {angstrom}) where the magnitude of the spin-orbit splitting is strongly geometry dependent. Perturbative models for incorporating the energetic effect of spin-orbit splitting into barrierless kinetics are presented and tested. Simply neglecting the variation in the spin-orbit splitting is demonstrated to contribute an error of less than 15% to the predicted rate coefficients for all but the CH{sub 2}CHCH{sub 2} + Br reaction, where its neglect increases the rate by up to a factor of 2. For the CH{sub 2}CHCH{sub 2} + Br reaction, the effect of spin-orbit splitting is not perturbative and instead qualitatively changes the long-range interaction potential and association dynamics. The present theoretical predictions are compared with available experimental measurements and previous theoretical work. For the CH{sub 3} + F association reaction, the errors associated with limitations in the basis set and in the active space are studied, and a detailed comparison is made between VRC-TST and rigid rotor-harmonic oscillator variational TST.

Jasper, A. W.; Klippenstein, S. J.; Harding, L. B. (Chemical Sciences and Engineering Division); (SNL)

2010-01-01T23:59:59.000Z

177

Origin of the metallicity distribution of the NGC 5128 stellar halo  

E-Print Network (OSTI)

Recent {\\it Hubble Space Telescope} photometry in the nearby elliptical galaxy NGC 5128 shows that its halo field star population is dominated by moderately metal-rich stars, with a peak at [m/H] $\\simeq$ -0.4 and with a very small fraction of metal-poor ([m/H] $<$ -1.0) stars. In order to investigate the physical processes which may have produced this metallicity distribution function (MDF), we consider a model in which NGC 5128 is formed by merging of two major spiral galaxies. We find that the halo of an elliptical formed this way is predominantly populated by moderately metal-rich stars with [m/H] $\\sim$ -0.4 which were initially within the outer parts of the two merging discs and were tidally stripped during the merger. To match the NGC 5128 data, we find that the progenitor spiral discs must have rather steep metallicity gradients similar to the one defined by the Milky Way open clusters, as well as sparse metal-poor haloes (5% or less of the disc mass). Very few stars from the central bulges of the spiral galaxies end up in the halo, so the results are not sensitive to the relative sizes (bulge-to-disc ratios) or metallicities of the initial bulges. Finally, we discuss the effects on the globular cluster system (GCS). The emergent elliptical will end up with metal-poor halo clusters from the original spiral haloes, but with moderately metal-rich halo stars from the progenitor discs, thus creating a mean offset between the MDFs of the halo stars and the GCS.

Kenji Bekki; William E. Harris; Gretchen L. H. Harris

2002-12-27T23:59:59.000Z

178

TSC plasma halo simulation of a DIII-D vertical displacement episode  

SciTech Connect

A benchmark of the Tokamak Simulation Code (TSC) plasma halo model has been achieved by calibration against a DIII-D vertical displacement episode (VDE) consisting of vertical drift, thermal quench, and current quench. Inclusion of a 1-to 4-eV halo surrounding the main plasma was found to be necessary to match simulation and experimental results for plasma current decay, trajectory, toroidal and poloidal vessel currents, and magnetic probe and flux loop values for the entire VDE.

Sayer, R.O.; Peng, Y.K.M. [Oak Ridge National Lab., TN (United States); Jardin, S.C. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Kellman, A.G.; Wesley, J.C. [General Atomics, San Diego, CA (United States)

1993-01-01T23:59:59.000Z

179

Halo-Independent analysis of direct dark matter detection data for any WIMP interaction  

E-Print Network (OSTI)

The halo independent comparison of direct dark matter detection data eliminates the need to make any assumption on the uncertain local dark matter distribution and is complementary to the usual data comparison which required assuming a dark halo model for our galaxy. The method, initially proposed for WIMPs with spin-independent contact interactions, has been generalized to any other interaction and applied to recent data on "Light WIMPs".

Graciela B. Gelmini

2014-11-04T23:59:59.000Z

180

An Excursion Set Model of the Cosmic Web: The Abundance of Sheets, Filaments, and Halos  

Science Journals Connector (OSTI)

We discuss an analytic approach for modeling structure formation in sheets, filaments, and knots. This is accomplished by combining models of triaxial collapse with the excursion set approach: sheets are defined as objects that have collapsed along only one axis, filaments have collapsed along two axes, and halos are objects in which triaxial collapse is complete. In the simplest version of this approach, which we develop here, large-scale structure shows a clear hierarchy of morphologies: the mass in large-scale sheets is partitioned up among lower mass filaments, which themselves are made up of still lower mass halos. Our approach provides analytic estimates of the mass fraction in sheets, filaments, and halos and its evolution, for any background cosmological model and any initial fluctuation spectrum. In the currently popular ?CDM model, our analysis suggests that more than 99% of the cosmic mass is in sheets, and 72% in filaments, with mass larger than 1010 M? at the present time. For halos, this number is only 46%. Our approach also provides analytic estimates of how halo abundances at any given time correlate with the morphology of the surrounding large-scale structure and how halo evolution correlates with the morphology of large-scale structure.

Jiajian Shen; Tom Abel; H. J. Mo; Ravi K. Sheth

2006-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Voids in the Local Volume: a limit on appearance of a galaxy in a DM halo  

E-Print Network (OSTI)

Current explanation of the overabundance of dark matter subhalos in the Local Group (LG) indicates that there maybe a limit on mass of a halo, which can host a galaxy. This idea can be tested using voids in the distribution of galaxies: at some level small voids should not contain any (even dwarf) galaxies. We use observational samples complete to M_B = -12 with distances less than 8 Mpc to construct the void function (VF): the distribution of sizes of voids empty of any galaxies. There are ~30 voids with sizes ranging from 1 to 5 Mpc. We then study the distribution of dark matter halos in very high resolution simulations of the LCDM model. The theoretical VF matches the observations remarkably well only if we use halos with circular velocities larger than 45 +/- 10 km/s. This agrees with the Local Group predictions. There are smaller halos in the voids, but they should not produce any luminous matter. Small voids look quite similar to their giant cousins: the density has a minimum at the center of a void and it increases as we get closer to the border. Small nonluminous halos inside the void form a web of tiny filaments. Thus, both the Local Group data and the nearby voids indicate that isolated halos below 45 +/- 10 km/s must not host galaxies and that small (few Mpc) voids are truly dark.

Anton V. Tikhonov; Anatoly A. Klypin

2007-07-24T23:59:59.000Z

182

An Excursion Set Model of the Cosmic Web: the Abundance of Sheets, Filaments And Halos  

SciTech Connect

We discuss an analytic approach for modeling structure formation in sheets, filaments and knots. This is accomplished by combining models of triaxial collapse with the excursion set approach: sheets are defined as objects which have collapsed along only one axis, filaments have collapsed along two axes, and halos are objects in which triaxial collapse is complete. In the simplest version of this approach, which we develop here, large scale structure shows a clear hierarchy of morphologies: the mass in large-scale sheets is partitioned up among lower mass filaments, which themselves are made-up of still lower mass halos. Our approach provides analytic estimates of the mass fraction in sheets, filaments and halos, and its evolution, for any background cosmological model and any initial fluctuation spectrum. In the currently popular {Lambda}CDM model, our analysis suggests that more than 99% of the mass in sheets, and 72% of the mass in filaments, is stored in objects more massive than 10{sup 10}M{sub {circle_dot}} at the present time. For halos, this number is only 46%. Our approach also provides analytic estimates of how halo abundances at any given time correlate with the morphology of the surrounding large-scale structure, and how halo evolution correlates with the morphology of large scale structure.

Shen, Jiajian; /Penn State U., Astron. Astrophys.; Abel, Tom; /KIPAC, Menlo Park; Mo, Houjun; /Massachusetts U., Amherst; Sheth, Ravi; /Pennsylvania U.

2006-01-11T23:59:59.000Z

183

Gamma-ray halo around the M31 galaxy as seen by the Fermi LAT  

E-Print Network (OSTI)

Theories of galaxy formation predict the existence of extended gas halo around spiral galaxies. If there are 10-100 nG magnetic fields at several ten kpc distances from the galaxies, extended galactic cosmic ray (CR) haloes could also exist. Galactic CRs could interact with the tenuous hot halo gas to produce observable $\\gamma$-rays. In this paper we have performed search for such a halo around the M31 galaxy -- the closest large spiral galaxy. Our analysis of 5.5 years of the Fermi LAT data revealed the presence of a spatially extended emission excess around M31. The data can be fitted using the simplest morphology of a uniformly bright circle. The best fit gave a 4.4$\\sigma$ significance for a $3^{\\circ}$ (40 kpc) halo with photon flux of $\\sim (1.9\\pm1.1)\\times 10^{-9} ~\\mathrm{cm^{-2}s^{-1}}$ and luminosity $(8.4\\pm4.6)\\times 10^{38} ~\\mathrm{erg~s^{-1}}$ in the energy range 0.3--100 GeV. The presence of such a halo compellingly shows that a 10-100 nG magnetic field should extend around M31 up to a 40 kp...

Pshirkov, M S; Postnov, K A

2015-01-01T23:59:59.000Z

184

NOT DEAD YET: COOL CIRCUMGALACTIC GAS IN THE HALOS OF EARLY-TYPE GALAXIES  

SciTech Connect

We report new observations of circumgalactic gas in the halos of early-type galaxies (ETGs) obtained by the COS-Halos Survey with the Cosmic Origins Spectrograph on board the Hubble Space Telescope. We find that detections of H I surrounding ETGs are typically as common and strong as around star-forming galaxies, implying that the total mass of circumgalactic material is comparable in the two populations. For ETGs, the covering fraction for H I absorption above 10{sup 16} cm{sup -2} is {approx}40%-50% within {approx}150 kpc. Line widths and kinematics of the detected material show it to be cold (T {approx}< 10{sup 5} K) in comparison to the virial temperature of the host halos. The implied masses of cool, photoionized circumgalactic medium baryons may be up to 10{sup 9}-10{sup 11} M{sub Sun }. Contrary to some theoretical expectations, strong halo H I absorbers do not disappear as part of the quenching of star formation. Even passive galaxies retain significant reservoirs of halo baryons that could replenish the interstellar gas reservoir and eventually form stars. This halo gas may feed the diffuse and molecular gas that is frequently observed inside ETGs.

Thom, Christopher; Tumlinson, Jason; Sembach, Kenneth R. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Werk, Jessica K.; Xavier Prochaska, J. [UCO/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States); Oppenheimer, Benjamin D. [Leiden Observatory, Leiden University, P.O. Box 9513, NL-2300 RA Leiden (Netherlands); Peeples, Molly S. [Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, CA 90095 (United States); Tripp, Todd M.; Katz, Neal S. [Department of Astronomy, University of Massachusetts, Amherst, MA 01003-9305 (United States); O'Meara, John M. [Department of Chemistry and Physics, Saint Michael's College, Colchester, VT 05439 (United States); Ford, Amanda Brady; Dave, Romeel [Steward Observatory, University of Arizona, 933 N. Cherry Avenue, Tucson, AZ 85721 (United States); Weinberg, David H. [Department of Astronomy, Ohio State University, 140 W. 18th Avenue, Columbus, OH 43210 (United States)

2012-10-20T23:59:59.000Z

185

Direct collapse black hole formation from synchronized pairs of atomic cooling halos  

E-Print Network (OSTI)

High-redshift quasar observations imply that supermassive black holes (SMBHs) larger than $\\sim 10^9 ~ M_\\odot$ formed before $z=6$. That such large SMBHs formed so early in the Universe remains an open theoretical problem. One possibility is that gas in atomic cooling halos exposed to strong Lyman-Werner (LW) radiation forms $10^4-10^6 ~ M_\\odot$ supermassive stars which quickly collapse into black holes. We propose a scenario for direct collapse black hole (DCBH) formation based on synchronized pairs of pristine atomic cooling halos. We consider halos at very small separation with one halo being a subhalo of the other. The first halo to surpass the atomic cooling threshold forms stars. Soon after these stars are formed, the other halo reaches the cooling threshold and due to its small distance from the newly formed galaxy, is exposed to the critical LW intensity required to form a DCBH. The main advantage of this scenario is that synchronization can potentially prevent photoevaporation and metal pollution i...

Visbal, Eli; Bryan, Greg L

2014-01-01T23:59:59.000Z

186

Linear response of galactic halos to adiabatic gravitational perturbations  

E-Print Network (OSTI)

We determine the response of a self-similar isothermal stellar system to small adiabatic gravitational perturbations. For odd spherical harmonics, the response is identical to the response of the analogous isothermal fluid system. For even spherical harmonics, the response can be regarded as an infinite series of wavetrains in $\\log r$, implying alternating compression and rarefaction in equal logarithmic radius intervals. Partly because of the oscillatory nature of the solutions, tidal fields from external sources are not strongly amplified by an intervening isothermal stellar system, except at radii $\\lta 10^{-3.5}$ times the satellite radius; at some radii the stellar system can even screen the external tidal field in a manner analogous to Debye screening. As Weinberg has pointed out, individual resonances in a stellar system can strongly amplify external tidal fields over a limited radial range, but we cannot address this possibility because we examine only adiabatic perturbations. We also discuss the application of our method to the halo response caused by the slow growth of an embedded thin disk.

Chigurupati Murali; Scott Tremaine

1997-09-14T23:59:59.000Z

187

Planck's confirmation of the M31 disk and halo rotation  

E-Print Network (OSTI)

Planck's data acquired during the first 15.4 months of observations towards both the disk and halo of the M31 galaxy are analyzed. We confirm the existence of a temperature asymmetry, previously detected by using the 7-year WMAP data, along the direction of the M31 rotation, therefore indicative of a Doppler-induced effect. The asymmetry extends up to about 10 degrees (about 130 kpc) from the M31 center. We also investigate the recent issue raised in Rubin and Loeb (2014) about the kinetic Sunyaev-Zeldovich effect from the diffuse hot gas in the Local Group, predicted to generate a hot spot of a few degrees size in the CMB maps in the direction of M31, where the free electron optical depth gets the maximum value. We also consider the issue whether in the opposite direction with respect to the M31 galaxy the same effect induces a minimum in temperature in the Planck's maps of the sky. We find that the Planck's data at 100 GHz show an effect even larger than that expected.

De Paolis, F; Nucita, A A; Ingrosso, G; Kashin, A L; Khachatryan, H G; Mirzoyan, S; Poghosian, E; Jetzer, Ph; Qadir, A; Vetrugno, D

2014-01-01T23:59:59.000Z

188

Testing gravity with halo density profiles observed through gravitational lensing  

SciTech Connect

We present a new test of the modified gravity endowed with the Vainshtein mechanism with the density profile of a galaxy cluster halo observed through gravitational lensing. A scalar degree of freedom in the galileon modified gravity is screened by the Vainshtein mechanism to recover Newtonian gravity in high-density regions, however it might not be completely hidden on the outer side of a cluster of galaxies. Then the modified gravity might yield an observational signature in a surface mass density of a cluster of galaxies measured through gravitational lensing, since the scalar field could contribute to the lensing potential. We investigate how the transition in the Vainshtein mechanism affects the surface mass density observed through gravitational lensing, assuming that the density profile of a cluster of galaxies follows the original Navarro-Frenk-White (NFW) profile, the generalized NFW profile and the Einasto profile. We compare the theoretical predictions with observational results of the surface mass density reported recently by other researchers. We obtain constraints on the amplitude and the typical scale of the transition in the Vainshtein mechanism in a subclass of the generalized galileon model.

Narikawa, Tatsuya; Yamamoto, Kazuhiro, E-mail: narikawa@theo.phys.sci.hiroshima-u.ac.jp, E-mail: kazuhiro@hiroshima-u.ac.jp [Department of Physical Science, Hiroshima University, Higashi-Hiroshima 739-8526 (Japan)

2012-05-01T23:59:59.000Z

189

ACCURATE UNIVERSAL MODELS FOR THE MASS ACCRETION HISTORIES AND CONCENTRATIONS OF DARK MATTER HALOS  

SciTech Connect

A large amount of observations have constrained cosmological parameters and the initial density fluctuation spectrum to a very high accuracy. However, cosmological parameters change with time and the power index of the power spectrum dramatically varies with mass scale in the so-called concordance LAMBDACDM cosmology. Thus, any successful model for its structural evolution should work well simultaneously for various cosmological models and different power spectra. We use a large set of high-resolution N-body simulations of a variety of structure formation models (scale-free, standard CDM, open CDM, and LAMBDACDM) to study the mass accretion histories, the mass and redshift dependence of concentrations, and the concentration evolution histories of dark matter halos. We find that there is significant disagreement between the much-used empirical models in the literature and our simulations. Based on our simulation results, we find that the mass accretion rate of a halo is tightly correlated with a simple function of its mass, the redshift, parameters of the cosmology, and of the initial density fluctuation spectrum, which correctly disentangles the effects of all these factors and halo environments. We also find that the concentration of a halo is strongly correlated with the universe age when its progenitor on the mass accretion history first reaches 4% of its current mass. According to these correlations, we develop new empirical models for both the mass accretion histories and the concentration evolution histories of dark matter halos, and the latter can also be used to predict the mass and redshift dependence of halo concentrations. These models are accurate and universal: the same set of model parameters works well for different cosmological models and for halos of different masses at different redshifts, and in the LAMBDACDM case the model predictions match the simulation results very well even though halo mass is traced to about 0.0005 times the final mass, when cosmological parameters and the power index of the initial density fluctuation spectrum have changed dramatically. Our model predictions also match the PINOCCHIO mass accretion histories very well, which are much independent of our numerical simulations and our definitions of halo merger trees. These models are also simple and easy to implement, making them very useful in modeling the growth and structure of dark matter halos. We provide appendices describing the step-by-step implementation of our models. A calculator which allows one to interactively generate data for any given cosmological model is provided on the Web, together with a user-friendly code to make the relevant calculations and some tables listing the expected concentration as a function of halo mass and redshift in several popular cosmological models. We explain why LAMBDACDM and open CDM halos on nearly all mass scales show two distinct phases in their mass growth histories. We discuss implications of the universal relations we find in connection to the formation of dark matter halos in the cosmic density field.

Zhao, D. H.; Jing, Y. P. [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, CAS, 80 Nandan Road, Shanghai 200030 (China); Mo, H. J. [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States); Boerner, G., E-mail: dhzhao@shao.ac.c [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Strasse 1, 85748 Garching (Germany)

2009-12-10T23:59:59.000Z

190

On the usage of Flaring Gas Layers to determine the Shape of Dark Matter Halos  

E-Print Network (OSTI)

I present a new method of deriving the shape of the dark matter (DM) halos of spiral galaxies. The method relies on the comparison of model predictions with high spectral and spatial resolution HI observations of the gas layer. The potential arising from the {\\em total} mass distribution of the galaxy is used in the calculation of the vertical distribution of the gas. I developed a new algorithm to calculate the force field of an arbitrary, azimuthally symmetric, density distribution. This algorithm is used to calculate the forces due to the radially truncated stellar disk as well as of the flaring gas layer. I use a simple two-parameter family of disk-halo models which have essentially the same observed equatorial rotation curve but different vertical forces. This mass model is composed of a stellar disk with constant M/L, and a DM-halo with a given axial ratio. I approximate the radial force due to the gaseous disk, and iteratively determine the vertical force due to the global distribution of the gas. The thickness of the gaseous disk is sensitive to both the flattening of the DM-halo and the self-gravity of the gas, but not to the particular choice of disk-halo decomposition. I show that the determination of the thickness of the gas layer is not restricted to edge-on galaxies, but can be measured for moderately inclined systems as well.

Rob P. Olling

1995-05-02T23:59:59.000Z

191

Nuclear halo of a 177\\,MeV proton beam in water  

E-Print Network (OSTI)

The dose distribution of a pencil beam in a water tank consists of a core, a halo and an aura. The core consists of primary protons which suffer multiple Coulomb scattering (MCS) and slow down by multiple collisions with atomic electrons (Bethe-Bloch theory). The halo consists of charged secondaries, many of them protons, from elastic interactions with H, elastic and inelastic interactions with O, and nonelastic interactions with O. We show that the halo radius is roughly one third of the beam range. The aura consists of neutral secondaries (neutrons and gamma rays) and the charged particles they set in motion. We have measured the core/halo at 177 MeV using a test beam offset in a water tank. The beam monitor was a plane parallel ionization chamber (IC) and the field IC a dose calibrated Exradin T1. Our dose measurements are absolute. We took depth-dose scans at ten displacements from the beam axis ranging from 0 to 10 cm. The dose spans five orders of magnitude, and the transition from halo to aura is obvio...

Gottschalk, Bernard; Daartz, Juliane; Wagner, Miles S

2014-01-01T23:59:59.000Z

192

VISITORS FROM THE HALO: 11 Gyr OLD WHITE DWARFS IN THE SOLAR NEIGHBORHOOD  

SciTech Connect

We report the discovery of three nearby old halo white dwarf (WD) candidates in the Sloan Digital Sky Survey (SDSS), including two stars in a common proper motion binary system. These candidates are selected from our 2800deg{sup 2} proper motion survey on the Bok and U.S. Naval Observatory Flagstaff Station 1.3 m telescopes, and they display proper motions of 0.''4-0.''5 yr{sup -1}. Follow-up MMT spectroscopy and near-infrared photometry demonstrate that all three objects are hydrogen-dominated atmosphere WDs with T {sub eff} {approx} 3700-4100 K. For average mass WDs, these temperature estimates correspond to cooling ages of 9-10 Gyr, distances of 70-80 pc, and tangential velocities of 140-200 km s{sup -1}. Based on the UVW space velocities, we conclude that they most likely belong to the halo. Furthermore, the combined main-sequence and WD cooling ages are 10-11 Gyr. Along with SDSS J1102+4113, they are the oldest field WDs currently known. These three stars represent only a small fraction of the halo WD candidates in our proper motion survey, and they demonstrate that deep imaging surveys like the Pan-STARRS and Large Synoptic Survey Telescope should find many old thick disk and halo WDs that can be used to constrain the age of the Galactic thick disk and halo.

Kilic, Mukremin; Brown, Warren R.; McLeod, B. [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Munn, Jeffrey A.; Harris, Hugh C. [US Naval Observatory, P.O. Box 1149, Flagstaff, AZ 86002 (United States); Williams, Kurtis A.; DeGennaro, Steven [Department of Astronomy, 1 University Station C1400, Austin, TX 78712 (United States); Kowalski, P. M. [Helmholtz-Centre Potsdam-GFZ German Research Centre for Geosciences, D-14473 Potsdam (Germany); Von Hippel, Ted [Physics Department, Siena College, 515 Loudon Road, Loudonville, NY 12211 (United States); Jeffery, Elizabeth J., E-mail: mkilic@cfa.harvard.ed [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

2010-05-20T23:59:59.000Z

193

Combining weak lensing tomography with halo clustering to probe dark energy  

Science Journals Connector (OSTI)

Two methods of constraining the properties of dark energy are weak lensing tomography and cluster counting. Uncertainties in mass calibration of clusters can be reduced by using the properties of halo clustering (the clustering of clusters). However, within a single survey, weak lensing and halo clustering probe the same density fluctuations. We explore the question of whether this information can be used twice—once in weak lensing and then again in halo clustering to calibrate cluster masses—or whether the combined dark energy constraints are weaker than the sum of the individual constraints. For a survey like the Dark Energy Survey (DES), we find that the cosmic shearing of source galaxies at high redshifts is indeed highly correlated with halo clustering at lower redshifts. Surprisingly, this correlation does not degrade cosmological constraints for a DES-like survey, and in fact, constraints are marginally improved since the correlations themselves act as additional observables. This considerably simplifies the analysis for a DES-like survey: when weak lensing and halo clustering are treated as independent experiments, the combined dark energy constraints (cluster counts included) are accurate if not slightly conservative. Our findings mirror those of Takada and Bridle, who investigated correlations between the cosmic shear and cluster counts.

Charles Shapiro and Scott Dodelson

2007-10-18T23:59:59.000Z

194

Development of Advanced Beam Halo Diagnostics at the Jefferson Lab Free-Electron-Laser Facility  

SciTech Connect

High average current and high brightness electron beams are needed for many applications. At the Jefferson Lab FEL facility, the search for dark matter with the FEL laser beam has produced some interesting results, and a second very promising experiment called ?DarkLight?, using the JLab Energy-recovery-linac (ERL) machine has been put forward. Although the required beam current has been achieved on this machine, one key challenge is the management of beam halo. At the University of Md. (UMD) we have demonstrated a high dynamic range halo measurement method using a digital micro-mirror array device (DMD). A similar system has been established at the JLab FEL facility as a joint effort by UMD and JLab to measure the beam halo on the high current ERL machine. Preliminary experiments to characterize the halo were performed on the new UV FEL. In this paper, the limitations of the present system will be analyzed and a discussion of other approaches (such as an optimized coronagraph) for further extending the dynamic range will be presented. We will also discuss the possibility of performing both longitudinal and transverse (3D) halo measurements together on a single system.

Shukui Zhang, Stephen Benson, Dave Douglas, Frederick Wilson, Hao Zhang, Anatoly Shkvarunets, Ralph Fiorito

2011-03-01T23:59:59.000Z

195

Beyond Halo Mass: Galactic Conformity as a Smoking Gun of Central Galaxy Assembly Bias  

E-Print Network (OSTI)

Quenched central galaxies tend to reside in a preferentially quenched large-scale environment, a phenomenon that has been dubbed galactic conformity. Remarkably, this tendency persists out to scales far larger than the virial radius of the halo hosting the central. Therefore, conformity manifestly violates the widely adopted assumption that the dark matter halo mass Mvir exclusively governs galaxy occupation statistics. This paper is the first in a series studying the implications of the observed conformity signal for the galaxy-dark matter connection. We show that recent measurements of conformity on scales R ~1-5 Mpc imply that central galaxy quenching statistics cannot be correctly predicted with the knowledge of Mvir alone. We also demonstrate that ejected (or `backsplash') satellites cannot give rise to the signal. We then invoke the age matching model, which is predicated on the co-evolution of galaxies and halos. We find that this model produces a strong signal, and that central galaxies are solely res...

Hearin, Andrew P; Bosch, Frank C van den

2014-01-01T23:59:59.000Z

196

Search for dark matter from the Galactic halo with the IceCube Neutrino Telescope  

Science Journals Connector (OSTI)

Self-annihilating or decaying dark matter in the Galactic halo might produce high energy neutrinos detectable with neutrino telescopes. We have conducted a search for such a signal using 276 days of data from the IceCube 22-string configuration detector acquired during 2007 and 2008. The effect of halo model choice in the extracted limit is reduced by performing a search that considers the outer halo region and not the Galactic Center. We constrain any large-scale neutrino anisotropy and are able to set a limit on the dark matter self-annihilation cross section of ??Av??10-22??cm3?s-1 for weakly interacting massive particle masses above 1 TeV, assuming a monochromatic neutrino line spectrum.

R. Abbasi et al. (IceCube Collaboration)

2011-07-29T23:59:59.000Z

197

ITO-free organic solar cells with roll-to-roll coated organic functional layers from non-halogenated solvents  

Science Journals Connector (OSTI)

Abstract This work reports on indium tin oxide (ITO)-free organic solar cells with roll to roll (R2R) processed organic functional layers. The device stack comprises a chromium–aluminum–chromium (Cr–Al–Cr) electron contact layer on a polyethylene terephthalate (PET) film, a photoactive layer of poly(3-hexylthiophene) (P3HT): (6,6)-phenyl C61 butyric acid methyl ester (PCBM), a hole transport layer of Poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) and a silver (Ag) grid for current collection. For the photoactive layer the non-halogenated solvent o-Xylene was used in order to reduce the impact on health and environment for R2R coating on ambient atmospheric conditions. The Cr–Al–Cr layers were sputtered onto the PET rolls in a batch process while the photoactive layer as well as the hole transport layer were applied in a continuous R2R process by slot die coating. The Ag grid was either thermally evaporated through a shadow mask as reference process or deposited by aerosol printing as a more production compatible process. Device efficiencies up to 2.9% on an active area of 1.1 cm2 were obtained with no difference for the method of grid processing. These experimental results demonstrate that R2R coated organic functional layers in ITO-free devices obtain the same device performance as compared to spin coated laboratory cells.

Deepak Kaduwal; Hans-Frieder Schleiermacher; Jan Schulz-Gericke; Thomas Kroyer; Birger Zimmermann; Uli Würfel

2014-01-01T23:59:59.000Z

198

Microscopic Self-consistent Study of Neon Halos with Resonant Contributions  

SciTech Connect

Recent reaction measurements have been interpreted as evidence of a halo structure in the exotic neutron-rich isotopes 29,31Ne. While theoretical studies of 31Ne generally agree on its halo nature, they differ significantly in their predictions of its properties and underlying cause (e.g., that 31Ne lies in an "island of inversion'"). We have made a systematic theoretical analysis of possible Neon halo signatures -- the first using a fully microscopic, relativistic mean field approach that properly treats positive energy orbitals (such as the valence neutron in 31Ne) self-consistently with bound levels, and that includes the pairing effect that keeps the nucleus loosely bound with negative Fermi energy. Our model is the analytical continuation of the coupling constant (ACCC) method based on a relativistic mean field (RMF) theory with Bardeen-Cooper-Schrieffer (BCS) pairing approximation. We calculate neutron- and matter-radii, one-neutron separation energies, p- and f-orbital energies and occupation probabilities, and neutron densities for single-particle resonant orbitals in 27-31Ne. We analyze these results for evidence of neutron halo formation in 29,31Ne. Our model predicts a p-orbit 1n halo structure for 31Ne, based on a radius increase from 30Ne that is 7 - 8 times larger than the increase from 29Ne to 30Ne, as well as a decrease in the neutron separation energy by a factor of ~ 10 compared to that of 27-30Ne. In contrast to other studies, our inclusion of resonances yields an inverted ordering of p and f orbitals for small deformations. Furthermore, we find no evidence of an s-orbit 1n halo in 29Ne as recently claimed in the literature.

Zhang, Shisheng [ORNL] [ORNL; Smith, Michael Scott [ORNL] [ORNL; Kang, Zhong-Shu [Beihang University, Beijing] [Beihang University, Beijing; Zhao, Jie [Chinese Academy of Sciences, INstitute of Theoretical Physics (ITP)] [Chinese Academy of Sciences, INstitute of Theoretical Physics (ITP)

2014-01-01T23:59:59.000Z

199

THE DARK MATTER HALO CONCENTRATION AND STELLAR INITIAL MASS FUNCTION OF A CASSOWARY GROUP  

SciTech Connect

We exploit the group environment of the CAmbridge Sloan Survey Of Wide ARcs in the skY z = 0.3 lens J2158+0257 to measure the group dynamical mass as a complement to the central dynamical and lensing mass constraints. Follow-up spectroscopy of candidate group members is performed using VLT/FORS2. From the resulting N = 21 confirmed members, we measure the group dynamical mass by calibrating an analytic tracer mass estimator with cosmological simulations. The luminosity-weighted line-of-sight velocity dispersion and the Einstein radius of the lens are used as mass probes in the inner regions of the galaxy. Combining these three observational probes allows us to independently constrain the mass and concentration of the dark matter halo, in addition to the total stellar mass of the central galaxy. We find a dark matter halo in remarkably good agreement with simulations (log{sub 10} M{sub 200}/M{sub Sun} = 14.2 {+-} 0.2, c{sub 200}= 4.4{sup +1.6}{sub -1.4}) and a stellar mass-to-light ratio which favors a Salpeter initial mass function ((M/L)* = 5.7 {+-} 1.2). Our measurement of a normal halo concentration suggests that there is no discrepancy between simulations and observations at the group mass scale. This is in contrast to the cluster mass scale for which a number of studies have claimed over-concentrated halos. While the halo mass is robustly determined, and the halo concentration is not significantly affected by systematics, the resulting stellar mass-to-light ratio is sensitive to the choice of stellar parameters, such as density profile and velocity anisotropy.

Deason, A. J. [Department of Astronomy and Astrophysics, University of California Santa Cruz, Santa Cruz, CA 95064 (United States); Auger, M. W.; Belokurov, V.; Evans, N. W., E-mail: alis@ucolick.org [Institute of Astronomy, Madingley Rd, Cambridge, CB3 0HA (United Kingdom)

2013-08-10T23:59:59.000Z

200

Reacción con borohidruro de sodio de 3, 3´-etilén-bis (3,4-dihidro-6-halo-sustituido-2h-1,3-benzoxazina) donde halo es: flúor, cloro, bromo y yodo / Reaction with sodium borohydride of 3, 3´-etylene-bis (3,4-dihydro-6-halo-substituted-2h-1,3-benzoxazine) where halo is: fluorine, chlorine, bromine and iodine .  

E-Print Network (OSTI)

??Rojas Salgado, Jicli José (2010) Reacción con borohidruro de sodio de 3, 3´-etilén-bis (3,4-dihidro-6-halo-sustituido-2h-1,3-benzoxazina) donde halo es: flúor, cloro, bromo y yodo / Reaction with… (more)

Rojas Salgado, Jicli José

2010-01-01T23:59:59.000Z

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201

SED, Metallicity and Age of Halo Globular Clusters in M33  

E-Print Network (OSTI)

In this paper we study the properties of ten halo globular clusters in the nearby spiral galaxy M33. CCD images of M33 were obtained as a part of the BATC Colour Survey of the sky in 13 intermediate-band filters from 3800 to 10000{\\AA}. By aperture photometry, we obtain the spectral energy distributions (SEDs) of these globular clusters. We estimate the ages of our sample clusters by comparing the photometry of each object with theoretical stellar population synthesis models for different values of metallicity. Our results suggest that eight of the ten sample halo globular clusters have ``intermediate'' ages, i.e. between 1 and 8 Gyrs.

Ma, J; Chen, J; Wu, H; Jiang, Z; Xue, S; Zhu, J; Ma, Jun; Zhou, Xu; Chen, Jiansheng; Wu, Hong; Jiang, Zhaoji; Xue, Suijian; Zhu, Jin

2002-01-01T23:59:59.000Z

202

MHD wave refraction and the acoustic halo effect around solar active regions - a 3D study  

E-Print Network (OSTI)

An enhancement in high-frequency acoustic power is commonly observed in the solar photosphere and chromosphere surrounding magnetic active regions. We perform 3D linear forward wave modelling with a simple wavelet pulse acoustic source to ascertain whether the formation of the acoustic halo is caused by MHD mode conversion through regions of moderate and inclined magnetic fields. This conversion type is most efficient when high frequency waves from below intersect magnetic field lines at a large angle. We find a strong relationship between halo formation and the equipartition surface at which the Alfv\\'en speed $a$ matches the sound speed $c$, lending support to the theory that photospheric and chromospheric halo enhancement is due to the creation and subsequent reflection of magnetically dominated fast waves from essentially acoustic waves as they cross $a=c$. In simulations where we have capped $a$ such that waves are not permitted to refract after reaching the $a=c$ height, halos are non-existent, which su...

Rijs, Carlos; Przybylski, Damien; Cally, Paul S

2015-01-01T23:59:59.000Z

203

Cosmic Ray Acceleration beyond the Knee up to the Ankle in the Galactic Wind Halo  

E-Print Network (OSTI)

Cosmic Ray Acceleration beyond the Knee up to the Ankle in the Galactic Wind Halo Vladimir the so-called knee at several #2;10 15 eV to the so-called ankle at a few #2;10 18 eV total energy

204

The Structure and Dark Halo Core Properties of Dwarf Spheroidal Galaxies  

E-Print Network (OSTI)

The structure and dark matter halo core properties of dwarf spheroidal galaxies (dSphs) are investigated. A double-isothermal model of an isothermal stellar system, embedded in an isothermal dark halo core provides an excellent fit to the various observed stellar surface density distributions. The stellar system can be well characterised by King profiles with a broad distribution of concentration parameters c. The core scale length of the stellar system a_* is sensitive to the central dark matter density rho_0. In contrast to single-component systems, the cut-off radius of the stellar system, rs_t, however does not trace the tidal radius but the core radius r_c of its dark matter halo. c is therefore sensitive to the ratio of the stellar to the dark matter velocity dispersion, sigma_*/sigma_0. Simple empirical relationships are derived that allow to calculate the dark halo core parameters rho_0, r_c and sigma_0, given the observable quantities sigma_*, a_* and c. The DIS model is applied to the Milky Way's dS...

Burkert, Andreas

2015-01-01T23:59:59.000Z

205

Application of Diamond and Sapphire Sensors in the Beam Halo Monitor for FLASH  

E-Print Network (OSTI)

, ionization chambers, a beam halo monitor (BHM) and beam position monitors (BPM) has been installed. The BHM, a BHM system and a magnetic BPM (also called "in-air" BPM) [8] operating in conjunction in order not hit the beam pipe downstream from the exit window. The BPM detects the center of gravity of the beam

206

Origin of strong magnetic fields in Milky Way-like galactic haloes  

Science Journals Connector (OSTI)

......process (column 2) triggers an MHD mechanism (column 3) operating...star formation rate. Figure 7 Diagram visualizing the flow of energy in the simulated MHD system. The star formation...supernova feedback are important in MHD simulations of galactic halo......

A. M. Beck; H. Lesch; K. Dolag; H. Kotarba; A. Geng; F. A. Stasyszyn

2012-05-21T23:59:59.000Z

207

Simulations of galaxies formed in warm dark matter halos of masses at the filtering scale  

E-Print Network (OSTI)

We present zoom-in N-body + Hydrodynamic simulations of dwarf central galaxies formed in Warm Dark Matter (WDM) halos with masses at present-day of $2-4\\times 10^{10}$ \\msun. Two different cases are considered, the first one when halo masses are close to the corresponding half-mode filtering scale \\Mhm\\ (\\mwdm =1.2 keV), and the second when they are 20 to 30 times the corresponding \\Mhm\\ (\\mwdm = 3.0 keV). The WDM simulations are compared with the respective Cold Dark Matter (CDM) simulations. The dwarfs formed in halos of masses (20-30)\\Mhm have roughly similar properties and evolution than their CDM counterparts; on the contrary, those formed in halos of masses around \\Mhm, are systematically different from their CDM counterparts. As compared to the CDM dwarfs, they assemble the dark and stellar masses later, having mass-weighted stellar ages 1.4--4.8 Gyr younger; their circular velocity profiles are shallower, with maximal velocities 20--60% lower; their stellar distributions are much less centrally concen...

Colin, Pedro; Gonzalez-Samaniego, Alejandro; Velazquez, Hector

2014-01-01T23:59:59.000Z

208

Halos generated by negative cloud-to-ground lightning H. U. Frey,1  

E-Print Network (OSTI)

are collected from about 20 msec before the triggering lightning flash up to 200 msec after it. It is thereforeHalos generated by negative cloud-to-ground lightning H. U. Frey,1 S. B. Mende,1 S. A. Cummer,2 J] The Imager for Sprites and Upper Atmospheric Lightning (ISUAL) on the FORMOSAT-2 spacecraft observes

Cummer, Steven A.

209

On the physics of radio haloes in galaxy clusters: scaling relations and luminosity functions  

Science Journals Connector (OSTI)

......Tier 1 survey at 120-MHz should be able to detect...the Coma halo at 352-MHz where not even the extreme...Fermi II acceleration at plasma waves). In particular...provided by Fermi and imaging atmospheric Cherenkov telescopes...we compute the 120-MHz RLF and the cumulative......

Fabio Zandanel; Christoph Pfrommer; Francisco Prada

2014-01-01T23:59:59.000Z

210

TSC simulation of feedback stabilization of axisymmetric modes in tokamaks using driven halo currents  

SciTech Connect

The Tokamak Simulation Code (TSC) has been used to model a new method of feedback stabilization of the axisymmetric instability in tokamaks using driven halo (or scrapeoff layer) currents. The method appears to be feasible for a wide range of plasma edge parameters. It may offer significant advantages over the more conventional method of controlling this instability when applied in a reactor environment.

Jardin, S.C.; Schmidt, J.A. [Princeton Univ., NJ (United States). Princeton Plasma Physics Lab.

1997-03-01T23:59:59.000Z

211

Rare measurements of a sprite with halo event driven by a negative lightning discharge over Argentina  

E-Print Network (OSTI)

Argentina M. J. Taylor,1 M. A. Bailey,1 P. D. Pautet,1 S. A. Cummer,2 N. Jaugey,2 J. N. Thomas,3,4 N. N measurements were made of a mesoscale thunderstorm observed on February 22­23, 2006 over northern Argentina of a sprite with halo event driven by a negative lightning discharge over Argentina, Geophys. Res. Lett., 35

Thomas, Jeremy N.

212

Lensing of 21cm Absorption "Halos" of $z\\sim$20-30 First Galaxies  

E-Print Network (OSTI)

Extended 21cm absorption regions (dubbed ``21cm absorption halos'') around first galaxies at $z\\sim 30$ are likely the first distinctive structures accessible to radio observations. Though the radio array capable of detecting and resolving them must have $\\sim 200$ km$^2$ total collecting area, given the great impact of such detections to the understanding of the reionization process and cosmology, such radio survey would be extremely profitable. As an example, we point out a potentially useful byproduct of such survey. The resolved 21cm absorption ``halos'', likely close to spherical, can serve as (almost) ideal sources for measuring the {\\it cosmic shear} and mapping the matter distribution to $z\\sim 30$. We investigate the expected lensing signal and consider a variety of noise contributions on the shear measurement. We find that S/N $\\sim 1$ can be achieved for individual ``halos''. Given millions of 21cm absorption ``halos'' across the sky, the total S/N will be comparable to traditional shear measurement of $\\sim$$10^9$ galaxies at $z\\sim 1$.

Pengjie Zhang; Zheng Zheng; Renyue Cen

2006-08-13T23:59:59.000Z

213

The cluster-core model for halo-structure of light nuclei at the drip lines  

E-Print Network (OSTI)

Nuclei at both the neutron- and proton-drip lines are studied. In the cluster-core model, the halo-structure of all the observed and proposed cases of neutron- or proton-halos is investigated in terms of simple potential energy surfaces calculated as the sum of binding energies, Coulomb repulsion, nuclear proximity attraction and the centrifugal potential for all the possible cluster+core configurations of a nucleus. The clusters of neutrons and protons are taken to be unbound, with additional Coulomb energy added for proton-clusters. The model predictions agree with the available experimental studies but show some differences with the nucleon separation energy hypothesis, particularly for proton-halo nuclei. Of particular interest are the halo-structures of $^{11}N$ and $^{20}Mg$. The calculated potential energy surfaces are also useful to identify the new magic numbers and molecular structures in exotic nuclei. In particular, N=6 is a possible new magic number for very neutron-deficient nuclei, but Z=N=2 and Z=8 seem to remain magic even for such nuclei, near the drip line.

Raj K. Gupta; Sushil Kumar; M. Balasubramaniam; G. Munzenberg; Werner Scheid

2011-11-08T23:59:59.000Z

214

Constraining the Milky Way's Hot Gas Halo with OVII and OVII Emission Lines  

E-Print Network (OSTI)

The Milky Way hosts a hot ($\\approx 2 \\times 10^6$ K), diffuse, gaseous halo based on detections of z = 0 OVII and OVIII absorption lines in quasar spectra and emission lines in blank-sky spectra. Here we improve constraints on the structure of the hot gas halo by fitting a radial model to a much larger sample of OVII and OVIII emission line measurements from XMM-Newton EPIC-MOS spectra compared to previous studies ($\\approx$ 650 sightlines). We assume a modified $\\beta$-model for the halo density distribution and a constant-density Local Bubble from which we calculate emission to compare with the observations. We find an acceptable fit to the OVIII emission line observations with $\\chi^{2}_{red}$ (dof) = 1.08 (644) for best-fit parameters of $n_o r_c^{3\\beta} = 1.35 \\pm 0.24$ cm$^{-3}$ kpc$^{3\\beta}$ and $\\beta = 0.50 \\pm 0.03$ for the hot gas halo and negligible Local Bubble contribution. The OVII observations yield an unacceptable $\\chi^{2}_{red}$ (dof) = 4.69 (645) for similar best-fit parameters, which i...

Miller, Matthew J

2014-01-01T23:59:59.000Z

215

Nuclear Halos and Drip Lines in Symmetry-Conserving Continuum HFB Theory  

E-Print Network (OSTI)

We review the properties of nuclear halos and nuclear skins in drip line nuclei in the framework of the spherical Hartree-Fock-Bogoliubov theory with continuum effects and projection on good particle number with the Gogny force. We first establish the position of the un-projected HFB drip lines for the two most employed parametrizations of the Gogny force and show that the use of finite-range interactions leads almost always to small-sized halos, even in the least bound nuclei, which is in agreement with most mean-field predictions. We also discuss the size of the neutron skin at the drip line and its relation to neutron asymmetry. The impact of particle-number projection and its conceptual consequences near the drip line are analyzed in detail. In particular, we discuss the role of the chemical potential in a projected theory and the criteria required to define the drip line. We show that including particle number projection can shift the latter, in particular near closed shells. We notice that, as a result, the size of the halo can be increased due to larger pairing correlations. However, combining the most realistic pairing interaction, a proper treatment of the continuum and particle number projection does not permit to reproduce the very large halos observed in very light nuclei.

N. Schunck; J. L. Egido

2008-09-23T23:59:59.000Z

216

THERMO-MECHANICAL RESPONSE OF THE HALO INTERCEPTS INTERACTING WITH THE SNS PROTON BEAM.  

SciTech Connect

Integral part of the primary collimator of the SNS accumulator ring is a halo intercept assembly in the form of movable scraper blades that allow interception of the halo protons in four planes. In order to achieve large coulomb scattering of the halo protons and energy losses of less than 1%, platinum was chosen as the material of choice while its thickness was optimized to satisfy the energy loss requirements. This paper outlines the adopted design of the scraper assembly and presents the thermal response of the system that intercepts the beam halo as well as the subsequent thermal stress analysis and the issues associated with the performance of the scraper. Specifically, the current design incorporates a highly conducting material (copper) in the blade structure interfacing with the platinum scraper and is responsible for conducting the deposited energy away from the beam interception region. The mechanical performance and durability of such system, especially of the special bonding between the dissimilar materials, is the primary focus of this effort.

SIMOS,N.; LUDEWIG,H.; CATALAN-LASHERAS,N.; BRODOWSKI,J.; WEI,J.

2001-06-18T23:59:59.000Z

217

Nonsingular density profiles of dark matter halos and Strong gravitational lensing  

E-Print Network (OSTI)

We use the statistics of strong gravitational lenses to investigate whether mass profiles with a flat density core are supported. The probability for lensing by halos modeled by a nonsingular truncated isothermal sphere (NTIS) with image separations greater than a certain value (ranging from zero to ten arcseconds) is calculated. NTIS is an analytical model for the postcollapse equilibrium structure of virialized objects derived by Shapiro, Iliev & Raga. This profile has a soft core and matches quite well with the mass profiles of dark matter-dominated dwarf galaxies deduced from their observed rotation curves. It also agrees well with the NFW (Navarro-Frenk-White) profile at all radii outside of a few NTIS core radii. Unfortunately, comparing the results with those for singular lensing halos (NFW and SIS+NFW) and strong lensing observations, the probabilities for lensing by NTIS halos are far too low. As this result is valid for any other nonsingular density profiles (with a large core radius), we conclude that nonsingular density profiles (with a large core radius) for CDM halos are ruled out by statistics of strong gravitational lenses.

Da-Ming Chen

2005-02-05T23:59:59.000Z

218

Photometry and the Metallicity Distribution of the Outer Halo of M31  

E-Print Network (OSTI)

We have conducted a wide-field CCD-mosaic study of the resolved red-giant branch (RGB) stars of M31, in a field located 20 kpc from the nucleus along the SE minor axis. In our (I, V-I) color-magnitude diagram, RGB stars in the top three magnitudes of the M31 halo are strongly present. Photometry of a more distant control field to subtract field contamination is used to derive the `cleaned' luminosity function and metallicity distribution function (MDF) of the M31 halo field. From the color distribution of the foreground Milky Way halo stars, we find a reddening E(V-I)= 0.10 +/- 0.02 for this field, and from the luminosity of the RGB tip, we determine a distance modulus (m-M)_o = 24.47 +/- 0.12 (= 783 +/- 43 kpc). The MDF is derived from interpolation within an extensive new grid of RGB models (Vandenberg et al. 2000). The MDF is dominated by a moderately high-metallicity population ([m/H]~ -0.5) found previously in more interior M31 halo/bulge fields, and is much more metal-rich than the [m/H]~ -1.5 level in the Milky Way halo. A significant (~30% - 40%, depending on AGB star contribution) metal-poor population is also present. To first order, the shape of the MDF resembles that predicted by a simple, single-component model of chemical evolution starting from primordial gas with an effective yield y=0.0055. It strongly resembles the MDF recently found for the outer halo of the giant elliptical NGC 5128 (Harris et al. 2000), though NGC 5128 has an even lower fraction of low-metallicity stars. Intriguingly, in both NGC 5128 and M31, the metallicity distribution of the globular clusters in M31 does not match the halo stars; the clusters are far more heavily weighted to metal-poor objects. We suggest similarities in the formation and early evolution of massive, spheroidal stellar systems.

Patrick R. Durrell; William E. Harris; Christopher J. Pritchet

2001-01-24T23:59:59.000Z

219

THE STELLAR METALLICITY DISTRIBUTION FUNCTION OF THE GALACTIC HALO FROM SDSS PHOTOMETRY  

SciTech Connect

We explore the stellar metallicity distribution function of the Galactic halo based on SDSS ugriz photometry. A set of stellar isochrones is calibrated using observations of several star clusters and validated by comparisons with medium-resolution spectroscopic values over a wide range of metal abundance. We estimate distances and metallicities for individual main-sequence stars in the multiply scanned SDSS Stripe 82, at heliocentric distances in the range 5-8 kpc and |b| > 35 Degree-Sign , and find that the in situ photometric metallicity distribution has a shape that matches that of the kinematically selected local halo stars from Ryan and Norris. We also examine independent kinematic information from proper-motion measurements for high Galactic latitude stars in our sample. We find that stars with retrograde rotation in the rest frame of the Galaxy are generally more metal poor than those exhibiting prograde rotation, which is consistent with earlier arguments by Carollo et al. that the halo system comprises at least two spatially overlapping components with differing metallicity, kinematics, and spatial distributions. The observed photometric metallicity distribution and that of Ryan and Norris can be described by a simple chemical evolution model by Hartwick (or by a single Gaussian distribution); however, the suggestive metallicity-kinematic correlation contradicts the basic assumption in this model that the Milky Way halo consists primarily of a single stellar population. When the observed metallicity distribution is deconvolved using two Gaussian components with peaks at [Fe/H] Almost-Equal-To -1.7 and -2.3, the metal-poor component accounts for {approx}20%-35% of the entire halo population in this distance range.

An, Deokkeun [Department of Science Education, Ewha Womans University, Seoul 120-750 (Korea, Republic of)] [Department of Science Education, Ewha Womans University, Seoul 120-750 (Korea, Republic of); Beers, Timothy C. [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States)] [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States); Johnson, Jennifer A.; Pinsonneault, Marc H. [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States)] [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Lee, Young Sun [Department of Physics and Astronomy and JINA (Joint Institute for Nuclear Astrophysics), Michigan State University, E. Lansing, MI 48824 (United States)] [Department of Physics and Astronomy and JINA (Joint Institute for Nuclear Astrophysics), Michigan State University, E. Lansing, MI 48824 (United States); Bovy, Jo [Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 (United States)] [Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 (United States); Ivezic, Zeljko [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States)] [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Carollo, Daniela [Macquarie University Research Centre in Astronomy, Astrophysics and Astrophotonics, Department of Physics and Astronomy, Macquarie University, NSW 2109 (Australia)] [Macquarie University Research Centre in Astronomy, Astrophysics and Astrophotonics, Department of Physics and Astronomy, Macquarie University, NSW 2109 (Australia); Newby, Matthew, E-mail: deokkeun@ewha.ac.kr [Department of Physics, Applied Physics and Astronomy, Rensselaer Polytechnic Institute Troy, NY 12180 (United States)] [Department of Physics, Applied Physics and Astronomy, Rensselaer Polytechnic Institute Troy, NY 12180 (United States)

2013-01-20T23:59:59.000Z

220

Accurate universal models for the mass accretion histories and concentrations of dark matter halos  

E-Print Network (OSTI)

A large amount of observations have constrained cosmological parameters and the initial density fluctuation spectrum to a very high accuracy. However, cosmological parameters change with time and the power index of the power spectrum varies with mass scale dramatically in the so-called concordance Lambda CDM cosmology. Thus, any successful model for its structural evolution should work well simultaneously for various cosmological models and different power spectra. We use a large set of high-resolution N-body simulations of a variety of structure formation models (scale-free, standard CDM, open CDM, and Lambda CDM) to study the mass accretion histories (MAHs), the mass and redshift dependence of concentrations and the concentration evolution histories of dark matter halos. We find that there is significant disagreement between the much-used empirical models in the literature and our simulations. According to two simple but tight correlations we find from the simulation results, we develop new empirical models for both the MAHs and the concentration evolution histories of dark matter halos, and the latter can also be used to predict the mass and redshift dependence of halo concentrations. These models are accurate and universal: the same set of model parameters works well for different cosmological models and for halos of different masses at different redshifts and the model predictions are highly accurate even when the histories are traced to very high redshift. These models are also simple and easy to implement. A web calculator and a user-friendly code to make the relevant calculations are available from http://www.shao.ac.cn/dhzhao/mandc.html . We explain why Lambda CDM halos on nearly all mass scales show two distinct phases in their evolution histories.

D. H. Zhao; Y. P. Jing; H. J. Mo; G. Boerner

2009-11-30T23:59:59.000Z

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221

Non-power law behavior of the radial profile of phase-space density of halos  

SciTech Connect

We study the pseudo phase-space density, ?(r)/?{sup 3}(r), of ?CDM dark matter halos with and without baryons (baryons+DM, and pure DM), by using the model introduced in Del Popolo (2009), which takes into account the effect of dynamical friction, ordered and random angular momentum, baryons adiabatic contraction and dark matter baryons interplay. We examine the radial dependence of ?(r)/?{sup 3}(r) over 9 orders of magnitude in radius for structures on galactic and cluster of galaxies scales. We find that ?(r)/?{sup 3}(r) is approximately a power-law only in the range of halo radius resolved by current simulations (down to 0.1% of the virial radius) while it has a non-power law behavior below the quoted scale, with inner profiles changing with mass. The non-power-law behavior is more evident for halos constituted both of dark matter and baryons while halos constituted just of dark matter and with angular momentum chosen to reproduce a Navarro-Frenk-White (NFW) density profile, are characterized by an approximately power-law behavior. The results of the present paper lead to conclude that density profiles of the NFW type are compatible with a power-law behavior of ?(r)/?{sup 3}(r), while those flattening to the halo center, like those found in Del Popolo (2009) or the Einasto profile, or the Burkert profile, cannot produce radial profile of the pseudo-phase-space density that are power-laws at all radii. The results argue against universality of the pseudo phase-space density and as a consequence argue against universality of density profiles constituted by dark matter and baryons as also discussed in Del Popolo (2009)

Popolo, A. Del, E-mail: adelpopolo@oact.inaf.it [Dipartimento di Fisica e Astronomia, University Of Catania, Viale Andrea Doria 6, 95125 Catania (Italy)

2011-07-01T23:59:59.000Z

222

RHAPSODY. I. STRUCTURAL PROPERTIES AND FORMATION HISTORY FROM A STATISTICAL SAMPLE OF RE-SIMULATED CLUSTER-SIZE HALOS  

SciTech Connect

We present the first results from the RHAPSODY cluster re-simulation project: a sample of 96 'zoom-in' simulations of dark matter halos of 10{sup 14.8{+-}0.05} h {sup -1} M {sub Sun }, selected from a 1 h {sup -3} Gpc{sup 3} volume. This simulation suite is the first to resolve this many halos with {approx}5 Multiplication-Sign 10{sup 6} particles per halo in the cluster mass regime, allowing us to statistically characterize the distribution of and correlation between halo properties at fixed mass. We focus on the properties of the main halos and how they are affected by formation history, which we track back to z = 12, over five decades in mass. We give particular attention to the impact of the formation history on the density profiles of the halos. We find that the deviations from the Navarro-Frenk-White (NFW) model and the Einasto model depend on formation time. Late-forming halos tend to have considerable deviations from both models, partly due to the presence of massive subhalos, while early-forming halos deviate less but still significantly from the NFW model and are better described by the Einasto model. We find that the halo shapes depend only moderately on formation time. Departure from spherical symmetry impacts the density profiles through the anisotropic distribution of massive subhalos. Further evidence of the impact of subhalos is provided by analyzing the phase-space structure. A detailed analysis of the properties of the subhalo population in RHAPSODY is presented in a companion paper.

Wu, Hao-Yi; Hahn, Oliver; Wechsler, Risa H.; Mao, Yao-Yuan; Behroozi, Peter S., E-mail: hywu@umich.edu [Kavli Institute for Particle Astrophysics and Cosmology, Physics Department, Stanford University, Stanford, CA 94305 (United States)

2013-02-15T23:59:59.000Z

223

Solid State Lighting ECE 198 Lab Manual  

E-Print Network (OSTI)

commonly available light bulbs: halogen, incandescent, compact fluorescent, and light-emitting diode (LED will look at the spectrum of the light emitted from the each light bulb, using the spectrometers you). Over the course of the lab, you will perform variety of tests on each of the light bulbs in order

Wasserman, Daniel M.

224

Thermal degradation of acrylonitrile–butadiene–styrene (ABS) containing flame retardants using a fluidized bed reactor: The effects of Ca-based additives on halogen removal  

Science Journals Connector (OSTI)

In this study, the thermal degradation of a waste fraction of acrylonitrile–butadiene–styrene containing brominated flame retardants was performed to reduce halogen content in the pyrolysis oil. Thermal degradation was completed using Ca-based additives (calcium oxide, calcium hydroxide and oyster shells) in a bench-scale pyrolysis plant equipped with a fluidized bed reactor and char separation system. Pyrolysis was carried out in a temperature range of 430–510 °C. In the absence of any additive, the oil yield amounted to about 77 wt.%. With the additives, the oil yield was markedly reduced to within a range of 45–64 wt.%. The principle compounds in the oils were toluene, ethylbenzene, styrene, cumene, ?-methylstyrene, phenol and heteroatom-containing compounds. When Ca(OH)2 was applied, total bromine and chlorine contents in the oil decreased to 0.05 and 0.04 wt.%, respectively. In addition, Ca(OH)2 reduced the antimony content in the oil to below 0.001 ppm. Most of the halogens and antimony in the feed material were present in the char obtained after pyrolysis.

Su-Hwa Jung; Seon-Jin Kim; Joo-Sik Kim

2012-01-01T23:59:59.000Z

225

Neutron-neutron correlation in the halo dissociation of light exotic nuclei  

Science Journals Connector (OSTI)

We present model results for the two-halo-neutron correlation functions, Cnn, for the dissociation process of light exotic nuclei modelled as two neutrons and a core. A minimum is predicted for Cnn as a function of the relative momentum of the two neutrons, pnn, due to the coherence of the neutrons in the halo and final state interaction. Studying the systems Be14, Li11, and He6 within this model, we show that the numerical asymptotic limit, Cnn?1, occurs only for pnn?400MeV/c, while such limit is reached for much lower values of pnn in an independent particle model as the one used in the analysis of recent experimental data. Our model is consistent with data once the experimental correlation function is appropriately normalized.

M. T. Yamashita; T. Frederico; Lauro Tomio

2005-07-18T23:59:59.000Z

226

The modified dynamics (MOND) predicts an absolute maximum to the acceleration produced by `dark halos'  

E-Print Network (OSTI)

We have recently discovered that the modified dynamics (MOND) implies some universal upper bound on the acceleration that can be contributed by a `dark halo'--assumed in a Newtonian analysis to account for the effects of MOND. Not surprisingly, the limit is of the order of the acceleration constant of the theory. This can be contrasted directly with the results of structure-formation simulations. The new limit is substantial and different from earlier MOND acceleration limits (discussed in connection with the MOND explanation of the Freeman law for galaxy disks, and the Fish law for ellipticals): It pertains to the `halo', and not to the observed galaxy; it is absolute, and independent of further physical assumptions on the nature of the galactic system; and it applies at all radii, whereas the other limits apply only to the mean acceleration in the system.

Rafael Brada; Mordehai Milgrom

1998-12-21T23:59:59.000Z

227

The outer regions of the giant Virgo galaxy M87 II. Kinematic separation of stellar halo and intracluster light  

E-Print Network (OSTI)

We present a spectroscopic study of 287 Planetary Nebulas (PNs) in a total area of ~0.4 deg^2 around the BCG M87 in Virgo A. With these data we can distinguish the stellar halo from the co-spatial intracluster light (ICL). PNs were identified from their narrow and symmetric redshifted lambda 5007\\4959 Angstrom [OIII] emission lines, and the absence of significant continuum. We implement a robust technique to measure the halo velocity dispersion from the projected phase-space to identify PNs associated with the M87 halo and ICL. The velocity distribution of the spectroscopically confirmed PNs is bimodal, containing a narrow component centred on the systemic velocity of the BCG and an off-centred broader component, that we identify as halo and ICL, respectively. Halo and ICPN have different spatial distributions: the halo PNs follow the galaxy's light, whereas the ICPNs are characterised by a shallower power-law profile. The composite PN number density profile shows the superposition of different PN populations...

Longobardi, Alessia; Gerhard, Ortwin; Hanuschik, Reinhard

2015-01-01T23:59:59.000Z

228

The Relationship Between Baryons and Dark Matter in Extended Galaxy Halos  

E-Print Network (OSTI)

The relationship between gas-rich galaxies and Ly-alpha absorbers is addressed in this paper in the context of the baryonic content of galaxy halos. Deep Arecibo HI observations are presented of two gas-rich spiral galaxies within 125 kpc projected distance of a Ly-alpha absorber at a similar velocity. The galaxies investigated are close to edge-on and the absorbers lie almost along their major axes, allowing for a comparison of the Ly-alpha absorber velocities with galactic rotation. This comparison is used to examine whether the absorbers are diffuse gas rotating with the galaxies' halos, outflow material from the galaxies, or intergalactic gas in the low redshift cosmic web. The results indicate that if the gas resides in the galaxies' halos it is not rotating with the system and possibly counter-rotating. In addition, simple geometry indicates the gas was not ejected from the galaxies and there are no gas-rich satellites detected down to 3.6 - 7.5 x 10^6 Msun, or remnants of satellites to 5-6 x 10^{18} cm^{-2}. The gas could potentially be infalling from large radii, but the velocities and distances are rather high compared to the high velocity clouds around the Milky Way. The most likely explanation is the galaxies and absorbers are not directly associated, despite the vicinity of the spiral galaxies to the absorbers (58-77 kpc from the HI edge). The spiral galaxies reside in a filament of intergalactic gas, and the gas detected by the absorber has not yet come into equilibrium with the galaxy. These results also indicate that the massive, extended dark matter halos of spiral galaxies do not commonly have an associated diffuse baryonic component at large radii.

M. E. Putman; J. L. Rosenberg; J. T. Stocke; R. McEntaffer

2005-10-11T23:59:59.000Z

229

Fusion and Direct Reactions of Halo Nuclei at Energies around the Coulomb Barrier  

E-Print Network (OSTI)

The present understanding of reaction processes involving light unstable nuclei at energies around the Coulomb barrier is reviewed. The effect of coupling to direct reaction channels on elastic scattering and fusion is investigated, with the focus on halo nuclei. A list of definitions of processes is given, followed by a review of the experimental and theoretical tools and information presently available. The effect of couplings on elastic scattering and fusion is studied with a series of model calculations within the coupled-channels framework. The experimental data on fusion are compared to "bare" no-coupling one-dimensional barrier penetration model calculations. On the basis of these calculations and comparisons with experimental data, conclusions are drawn from the observation of recurring features. The total fusion cross sections for halo nuclei show a suppression with respect to the "bare" calculations at energies just above the barrier that is probably due to single neutron transfer reactions. The data for total fusion are also consistent with a possible sub-barrier enhancement; however, this observation is not conclusive and other couplings besides the single-neutron channels would be needed in order to explain any actual enhancement. We find that a characteristic feature of halo nuclei is the dominance of direct reactions over fusion at near and sub-barrier energies; the main part of the cross section is related to neutron transfers, while calculations indicate only a modest contribution from the breakup process.

N. Keeley; R. Raabe; N. Alamanos; J. L. Sida

2007-02-16T23:59:59.000Z

230

Galactic halo origin of the neutrinos detected by IceCube  

Science Journals Connector (OSTI)

Recent IceCube results suggest that the first detection of very high energy astrophysical neutrinos have been accomplished. We consider these results at face value in a Galactic origin context. Emission scenarios from both the Fermi bubble and broader halo region are considered. We motivate that such an intensity of diffuse neutrino emission could be Galactic in origin if it is produced from an outflow into the halo region. This scenario requires cosmic ray transport within the outflow environment to be different to that inferred locally within the disk and that activity in the central part of the Galaxy accelerates cosmic rays to trans-“knee” energies before they escape into an outflow. The presence of a large reservoir of gas in a very extended halo around the Galaxy, recently inferred from x-ray observations, implies that the relatively modest acceleration power of 1039 erg s?1 in PeV energy cosmic rays may be sufficient to explain the observed neutrino flux. Such a luminosity is compatible with that required to explain the observed intensity of cosmic rays around the knee.

Andrew M. Taylor; Stefano Gabici; Felix Aharonian

2014-05-05T23:59:59.000Z

231

Modes of transference and rupture of the nucleus with neutron halos sup 6 He on sup 2 sup 0 sup 9 Bi near of the Coulomb barrier  

E-Print Network (OSTI)

Modes of transference and rupture of the nucleus with neutron halos sup 6 He on sup 2 sup 0 sup 9 Bi near of the Coulomb barrier

Lizcano, D

2003-01-01T23:59:59.000Z

232

,,,"Incandescent","Standard Fluorescent","Compact Fluorescent","High-Intensity Discharge","Halogen"  

U.S. Energy Information Administration (EIA) Indexed Site

B39. Lighting Equipment, Floorspace, 1999" B39. Lighting Equipment, Floorspace, 1999" ,"Total Floorspace (million square feet)" ,"All Buildings","All Lit Buildings","Lighting Equipment (more than one may apply)" ,,,"Incandescent","Standard Fluorescent","Compact Fluorescent","High-Intensity Discharge","Halogen" "All Buildings ................",67338,64321,38156,60344,20666,19223,17926 "Building Floorspace" "(Square Feet)" "1,001 to 5,000 ...............",6774,5859,2946,5154,738,245,600 "5,001 to 10,000 ..............",8238,7464,4047,6722,1108,663,991 "10,001 to 25,000 .............",11153,10393,6055,9815,1759,1701,1996 "25,001 to 50,000 .............",9311,9053,5004,8344,2296,2224,1611

233

Physicists change the light bulb  

Science Journals Connector (OSTI)

...came in such colors as red and green. They were used as indicator lights...which has enabled bright and energy-saving white light sources...and waste most of the input energy. “With 20% of the world's...people who are not connected to energy grids. The usefulness of this...

Dennis Normile

2014-10-10T23:59:59.000Z

234

DEEP 1.4 GHz FOLLOW-UP OF THE STEEP SPECTRUM RADIO HALO IN A521  

SciTech Connect

In a recent paper, we reported on the discovery of a radio halo with very steep spectrum in the merging galaxy cluster A521 through observations with the Giant Metrewave Radio Telescope. We showed that the steep spectrum of the halo is inconsistent with a secondary origin of the relativistic electrons and supports a turbulent acceleration scenario. At that time, due to the steep spectrum, the available observations at 1.4 GHz (archival NRAO-Very Large Array-VLA-CnB-configuration data) were not adequate to accurately determine the flux density associated with the radio halo. In this paper, we report the detection at 1.4 GHz of the radio halo in A521 using deep VLA observations in the D configuration. We use these new data to confirm the steep spectrum of the object. We consider A521 the prototype of a population of very steep spectrum halos. This population is predicted assuming that turbulence plays an important role in the acceleration of relativistic particles in galaxy clusters, and we expect it will be unveiled by future surveys at low frequencies with the LOFAR and LWA radio telescopes.

Dallacasa, D.; Macario, G.; Setti, G. [Dipartimento di Astronomia, Universita di Bologna, via Ranzani 1, I-40127 Bologna (Italy); Brunetti, G.; Cassano, R.; Venturi, T. [INAF-Istituto di Radioastronomia, via Gobetti 101, I-40129 Bologna (Italy); Giacintucci, S. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Kassim, N. E.; Lane, W. [Naval Research Laboratory, Code 7213, Washington, DC 20375-5320 (United States)

2009-07-10T23:59:59.000Z

235

Predicting Galaxy Star Formation Rates via the Co-evolution of Galaxies and Halos  

SciTech Connect

In this paper, we test the age matching hypothesis that the star formation rate (SFR) of a galaxy is determined by its dark matter halo formation history, and as such, that more quiescent galaxies reside in older halos. This simple model has been remarkably successful at predicting color-based galaxy statistics at low redshift as measured in the Sloan Digital Sky Survey (SDSS). To further test this method with observations, we present new SDSS measurements of the galaxy two-point correlation function and galaxy-galaxy lensing as a function of stellar mass and SFR, separated into quenched and star forming galaxy samples. We find that our age matching model is in excellent agreement with these new measurements. We also employ a galaxy group finder and show that our model is able to predict: (1) the relative SFRs of central and satellite galaxies, (2) the SFR-dependence of the radial distribution of satellite galaxy populations within galaxy groups, rich groups, and clusters and their surrounding larger scale environments, and (3) the interesting feature that the satellite quenched fraction as a function of projected radial distance from the central galaxy exhibits an approx r-.15 slope, independent of environment. The accurate prediction for the spatial distribution of satellites is intriguing given the fact that we do not explicitly model satellite-specific processes after infall, and that in our model the virial radius does not mark a special transition region in the evolution of a satellite, contrary to most galaxy evolution models. The success of the model suggests that present-day galaxy SFR is strongly correlated with halo mass assembly history.

Watson, Douglas F.; Hearin, Andrew P.; Berlind, Andreas A.; Becker, Matthew R.; Behroozi, Peter S.; Skibba, Ramin A.; Reyes, Reinabelle; Zentner, Andrew R.

2014-03-06T23:59:59.000Z

236

THE COS-HALOS SURVEY: RATIONALE, DESIGN, AND A CENSUS OF CIRCUMGALACTIC NEUTRAL HYDROGEN  

SciTech Connect

We present the design and methods of the COS-Halos survey, a systematic investigation of the gaseous halos of 44 z = 0.15-0.35 galaxies using background QSOs observed with the Cosmic Origins Spectrograph aboard the Hubble Space Telescope. This survey has yielded 39 spectra of z{sub em} ? 0.5 QSOs with S/N ?10-15 per resolution element. The QSO sightlines pass within 150 physical kpc of the galaxies, which span early and late types over stellar mass log M{sub *}/M{sub ?} = 9.5-11.5. We find that the circumgalactic medium exhibits strong H I, averaging ? 1 Å in Ly? equivalent width out to 150 kpc, with 100% covering fraction for star-forming galaxies and 75% covering for passive galaxies. We find good agreement in column densities between this survey and previous studies over similar range of impact parameter. There is weak evidence for a difference between early- and late-type galaxies in the strength and distribution of H I. Kinematics indicate that the detected material is bound to the host galaxy, such that ?> 90% of the detected column density is confined within ±200 km s{sup –1} of the galaxies. This material generally exists well below the halo virial temperatures at T ?< 10{sup 5} K. We evaluate a number of possible origin scenarios for the detected material, and in the end favor a simple model in which the bulk of the detected H I arises in a bound, cool, low-density photoionized diffuse medium that is generic to all L* galaxies and may harbor a total gaseous mass comparable to galactic stellar masses.

Tumlinson, Jason; Thom, Christopher; Sembach, Kenneth R. [Space Telescope Science Institute, Baltimore, MD (United States); Werk, Jessica K.; Prochaska, J. Xavier [UCO/Lick Observatory, University of California, Santa Cruz, CA (United States); Tripp, Todd M.; Katz, Neal; Meiring, Joseph D. [Department of Astronomy, University of Massachusetts, Amherst, MA (United States); Davé, Romeel [University of the Western Cape, South African Astronomical Observatories, and African Institute for Mathematical Sciences, Cape Town (South Africa); Oppenheimer, Benjamin D. [Leiden Observatory, Leiden University, 2300 RA Leiden (Netherlands); Ford, Amanda Brady [Steward Observatory, University of Arizona, Tucson, AZ (United States); O'Meara, John M. [Department of Chemistry and Physics, Saint Michael's College, Colchester, VT (United States); Peeples, Molly S. [Center for Galaxy Evolution, University of California Los Angeles, Los Angeles, CA (United States); Weinberg, David H. [Department of Astronomy, The Ohio State University, Columbus, OH (United States)

2013-11-01T23:59:59.000Z

237

Neutron halo and spin-orbit splitting in some neutron-rich nuclei  

Science Journals Connector (OSTI)

The density-dependent relativistic mean-field theory with ?, ?, and ? mesons, as a parameter-free calculation, has been used to study the ground-state properties of Be12,14, Ne30,32, Ca60,62, and Zr122,124. A special emphasis is placed on the influence of the ? tensor coupling on the neutron halo and on the spin-orbit splitting. It is shown for the first time that the inclusion of the ? tensor coupling will lead to the isospin-dependent spin-orbit splitting although the binding energy and the radius of these nuclei are insensitive to it.

Zhongzhou Ren; M. Mittig; Baoqiu Chen; Zhongyu Ma; G. Auger; Gongou Xu

1995-10-01T23:59:59.000Z

238

Photometry and the Metallicity Distribution of the Outer Halo of M31. II. The 30 Kpc Field  

E-Print Network (OSTI)

We present the results of a wide-field (V,I) photometric study of the red-giant branch (RGB) stars in the outer halo of M31, in a field located 30 to 35 kpc from the center of the galaxy along the southeast minor axis. At this remote location, we find that RGB stars belonging to M31 are sparsely but definitely present, after statistical subtraction of field contamination. We derive the metallicity distribution (MDF) for the halo stars using interpolation within a standard (I,V-I) grid of RGB evolutionary tracks. The halo MDF is quite broad but dominated by a moderately high-metallicity population peaking at [m/H] ~ -0.5, strikingly different from the [m/H] ~ -1.3 level which characterizes the outer halo of the Milky Way. However,the shape and peak metallicity for this region are entirely similar to those found in other studies for the inner regions of the M31 halo, particularly our previous study of a 20-kpc region (Durrell, Harris, & Pritchet 2001) employing similar data. In summary, we find no evidence for a metallicity gradient or systematic change in the MDF out to quite large distances in the M31 halo: it appears to be a homogeneous and moderately metal-rich subsystem of the galaxy at all locations. The star counts in the 30-kpc field are also consistent with the r^1/4 law that fits the interior regions of the M31 spheroid surface brightness profile. The metal-rich MDF and the r^1/4 spheroid suggests M31 more strongly resembles a giant elliptical galaxy than other, Milky-Way-like, spirals.

Patrick R. Durrell; William E. Harris; Christopher J. Pritchet

2004-05-20T23:59:59.000Z

239

Constraining the extension of a possible gamma-ray halo of 3C 279 from 2008-2014 solar occultations  

E-Print Network (OSTI)

The angular extension of the gamma-ray image of 3C 279 may be constrained by studying its solar occultations as suggested by Fairbairn et al. (2010). We perform this kind of analysis for seven occultations observed by Fermi-LAT in 2008-2014, using the Fermi-LAT Solar System tools. The results are interpreted in terms of models with extended gamma-ray halo of 3C 279; first constraints on the size and the flux of the halo are reported.

Kotelnikov, Egor; Troitsky, Sergey

2014-01-01T23:59:59.000Z

240

Magnesium Isotopes in Metal-Poor Dwarfs, the Rise of AGB Stars and the Formation Timescale of the Galactic Halo  

E-Print Network (OSTI)

We have determined magnesium isotopic ratios (^{25,26}Mg/Mg) in metal-poor (-2.6 [Fe/H] -1.3) halo dwarfs employing high S/N (90-280) high spectral resolution (R = 10^5) Keck HIRES spectra. Unlike previous claims of an important contribution from intermediate-mass AGB stars at low metallicities, we find that the rise of the AGB contribution in the Galactic halo did not occur until intermediate metallicities ([Fe/H] ~> -1.5).

Jorge Melendez; Judith G. Cohen

2007-02-24T23:59:59.000Z

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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241

Sensitivity of galaxy cluster dark energy constraints to halo modeling uncertainties  

Science Journals Connector (OSTI)

We perform a sensitivity study of dark energy (DE) constraints from galaxy cluster surveys to uncertainties in the halo mass function, bias, and the mass-observable relation. For a set of idealized surveys, we evaluate cosmological constraints as priors on 16 nuisance parameters in the halo modeling are varied. We find that surveys with a higher mass limit are more sensitive to mass-observable uncertainties while surveys with low mass limits that probe more of the mass-function shape and evolution are more sensitive to mass-function errors. We examine the correlations among nuisance and cosmological parameters. Mass-function parameters are strongly positively (negatively) correlated with ?DE (w). For the mass-observable parameters, ?DE is most sensitive to the normalization and its redshift evolution while w is more sensitive to redshift evolution in the variance. While survey performance is limited mainly by mass-observable uncertainties, the current level of mass-function error is responsible for up to a factor of 2 degradation in ideal cosmological constraints. For surveys that probe to low masses (1013.5h-1M?), even percent-level constraints on model nuisance parameters result in a degradation of ?2 (2) on ?DE (w) relative to perfect knowledge.

Carlos E. Cunha and August E. Evrard

2010-04-08T23:59:59.000Z

242

The structure of star clusters in the outer halo of M31  

E-Print Network (OSTI)

We present a structural analysis of halo star clusters in M31 based on deep Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) imaging. The clusters in our sample span a range in galactocentric projected distance from 13 to 100 kpc and thus reside in rather remote environments. Ten of the clusters are classical globulars, while four are from the Huxor et al. (2005, 2008) population of extended, old clusters. For most clusters, contamination by M31 halo stars is slight, and so the profiles can be mapped reliably to large radial distances from their centres. We find that the extended clusters are well fit by analytic King (1962) profiles with ~20 parsec core radii and ~100 parsec photometric tidal radii, or by Sersic profiles of index ~1 (i.e. approximately exponential). Most of the classical globulars also have large photometric tidal radii in the range 50-100 parsec, however the King profile is a less good fit in some cases, particularly at small radii. We find 60 of the classical globular cluster...

Tanvir, N R; Ferguson, A M N; Huxor, A; Read, J I; Lewis, G F; Irwin, M J; Chapman, S; Ibata, R; Wilkinson, M I; McConnachie, A W; Martin, N F; Davies, M B; Bridges, T J

2012-01-01T23:59:59.000Z

243

ON THE SIZE EVOLUTION OF A GALACTIC DISK IN HIERARCHICAL MERGING OF COLD DARK MATTER HALOS  

SciTech Connect

We investigate the dynamical effects of dark matter subhalos on the structure and evolution of a galactic disk, using the semi-analytic method that includes approximated and empirical relations as achieved in detailed numerical simulations of the cold dark matter model. We calculate the upper limit for the size of a galactic disk at a specific redshift z, based on the orbital properties of subhalos characterized by their pericentric distances from the center of a host halo. We find that this possibly largest size of a disk as determined by the smallest pericentric distances of subhalos shows the characteristic properties, which are basically in agreement with an observed galactic disk at low and high z. Namely, it is found that a massive disk can have a larger size than a less massive one, because of its stability against the destruction effect of subhalos. Also, with fixed mass, the size of a galactic disk at low z can be larger than that at high z, reflecting the orbital evolution of subhalos with respect to a host halo. These results suggest that the presence and structure of a galactic disk may be dynamically limited by the interaction with dark matter substructures, especially at high z.

Hayashi, Hirohito; Chiba, Masashi [Astronomical Institute, Tohoku University, Aoba-ku, Sendai 980-8578 (Japan)

2009-09-10T23:59:59.000Z

244

The Origin of the Hot Gas in the Galactic Halo: Testing Galactic Fountain Models' X-ray Emission  

E-Print Network (OSTI)

We test the X-ray emission predictions of galactic fountain models against XMM-Newton measurements of the emission from the Milky Way's hot halo. These measurements are from 110 sight lines, spanning the full range of Galactic longitudes. We find that a magnetohydrodynamical simulation of a supernova-driven interstellar medium, which features a flow of hot gas from the disk to the halo, reproduces the temperature but significantly underpredicts the 0.5-2.0 keV surface brightness of the halo (by two orders of magnitude, if we compare the median predicted and observed values). This is true for versions of the model with and without an interstellar magnetic field. We consider different reasons for the discrepancy between the model predictions and the observations. We find taking into account overionization in cooled halo plasma, which could in principle boost the predicted X-ray emission, is unlikely in practice to bring the predictions in line with the observations. We also find that including thermal conductio...

Henley, David B; Kwak, Kyujin; Hill, Alex S; Mac Low, Mordecai-Mark

2015-01-01T23:59:59.000Z

245

Imprints of dark energy on cosmic structure formation – II. Non-universality of the halo mass function  

Science Journals Connector (OSTI)

......g. the properties of dark energy) and redshift would be absent...especially in the context of dark energy cosmologies. Is the halo mass...conclusions in Section 7. 2 DARK ENERGY AND STRUCTURE FORMATION 2...for the ellipsoidal collapse (Audit, Teyssier Alimi 1997; Sheth......

J. Courtin; Y. Rasera; J.-M. Alimi; P.-S. Corasaniti; V. Boucher; A. Füzfa

2011-01-21T23:59:59.000Z

246

3D Spectroscopy of Wind Driven Nebulae: The Large Western Knot in the Halo of NGC 6543  

E-Print Network (OSTI)

spectroscopy 1 Introduction The history of stellar mass loss is written in the extended wind-driven nebulae would be required. A candidate for this extra energy source is the fast wind passing the cold3D Spectroscopy of Wind Driven Nebulae: The Large Western Knot in the Halo of NGC 6543 David Mart

Estalella, Robert

247

GALAXY HALO TRUNCATION AND GIANT ARC SURFACE BRIGHTNESS RECONSTRUCTION IN THE CLUSTER MACSJ1206.2-0847  

SciTech Connect

In this work, we analyze the mass distribution of MACSJ1206.2-0847, particularly focusing on the halo properties of its cluster members. The cluster appears relaxed in its X-ray emission, but has a significant amount of intracluster light that is not centrally concentrated, suggesting that galaxy-scale interactions are still ongoing despite the overall relaxed state. The cluster lenses 12 background galaxies into multiple images and one galaxy at z = 1.033 into a giant arc and its counterimage. The multiple image positions and the surface brightness (SFB) distribution of the arc, which is bent around several cluster members, are sensitive to the cluster galaxy halo properties. We model the cluster mass distribution with a Navarro-Frenk-White profile and the galaxy halos with two parameters for the mass normalization and the extent of a reference halo assuming scalings with their observed near-infrared light. We match the multiple image positions at an rms level of 0.''85 and can reconstruct the SFB distribution of the arc in several filters to a remarkable accuracy based on this cluster model. The length scale where the enclosed galaxy halo mass is best constrained is about 5 effective radii-a scale in between those accessible to dynamical and field strong-lensing mass estimates on the one hand and galaxy-galaxy weak-lensing results on the other hand. The velocity dispersion and halo size of a galaxy with m{sub 160W,AB} = 19.2 and M{sub B,Vega} = -20.7 are {sigma} = 150 km s{sup -1} and r Almost-Equal-To 26 {+-} 6 kpc, respectively, indicating that the halos of the cluster galaxies are tidally stripped. We also reconstruct the unlensed source, which is smaller by a factor of {approx}5.8 in area, demonstrating the increase in morphological information due to lensing. We conclude that this galaxy likely has star-forming spiral arms with a red (older) central component.

Eichner, Thomas; Seitz, Stella; Monna, Anna [Universitaets-Sternwarte Muenchen, Scheinerstr. 1, D-81679 Muenchen (Germany); Suyu, Sherry H. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Halkola, Aleksi [Institute of Medical Engineering, University of Luebeck, Ratzeburger Allee 160 23562 Luebeck (Germany); Umetsu, Keiichi [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China); Zitrin, Adi [Institut fuer Theoretische Astrophysik, ZAH, Albert-Ueberle-Strasse 2, D-69120 Heidelberg (Germany); Coe, Dan; Postman, Marc; Koekemoer, Anton; Bradley, Larry [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21208 (United States); Rosati, Piero [ESO-European Southern Observatory, D-85748 Garching bei Muenchen (Germany); Grillo, Claudio; Host, Ole [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Balestra, Italo [Max-Planck-Institut fuer Extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany); Zheng, Wei; Lemze, Doron [Department of Physics and Astronomy, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Broadhurst, Tom [Department of Theoretical Physics, University of the Basque Country, P.O. Box 644, E-48080 Bilbao (Spain); Moustakas, Leonidas [Jet Propulsion Laboratory, California Institute of Technology, MS 169-327, Pasadena, CA 91109 (United States); Molino, Alberto [Instituto de Astrofisica de Andalucia (CSIC), C/Camino Bajo de Huetor 24, Granada E-18008 (Spain); and others

2013-09-10T23:59:59.000Z

248

Fusion reactions with the one-neutron halo nucleus 15C  

E-Print Network (OSTI)

The structure of 15C, with an s1/2 neutron weakly bound to a closed-neutron shell nucleus 14C, makes it a prime candidate for a one-neutron halo nucleus. We have for the first time studied the cross section for the fusion-fission reaction 15C + 232Th at energies in the vicinity of the Coulomb barrier and compared it to the yield of the neighboring 14C + 232Th system measured in the same experiment. At sub-barrier energies, an enhancement of the fusion yield by factors of 2-5 was observed for 15C, while the cross sections for 14C match the trends measured for 12,13C.

M. Alcorta; K. E. Rehm; B. B. Back; S. Bedoor; P. F. Bertone; C. M. Deibel; B. DiGiovine; H. Esbensen; J. P. Greene; C. R. Hoffmann; C. L. Jiang; J. C. Lighthall; S. T. Marley; R. C. Pardo; M. Paul; A. M. Rogers; C. Ugalde; A. H. Wuosmaa

2011-04-06T23:59:59.000Z

249

Globular Cluster Mass and Metallicity Distributions: Reconstructing the Events During Halo Formation  

E-Print Network (OSTI)

Globular clusters in most large galaxies are a mixture of metal-poor and metal-rich (bimodal), but the halo stars are almost entirely metal-rich. This and other lines of evidence argue that the metal-poor globular clusters formed within widely distributed 10^8-10^9 Solar masses gas clouds (supergiant GMCs) during an early burst in which most of the gas was ejected or unused till later rounds of star formation. New simulations of the growth of pre-galactic potential wells in the early universe now indicate that the initial power-law form of the globular cluster mass distribution (dN/dM ~ M^-1.8) is a miniature replica of the mass distribution of the SGMCs themselves, which grow hierarchically in the CDM potential wells of large protogalaxies.

W. E. Harris

2001-08-22T23:59:59.000Z

250

Study on the One-Proton Halo Structure in $^{23}$Al  

E-Print Network (OSTI)

The Glauber theory has been used to investigate the reaction cross section of proton-rich nucleus $^{23}$Al. A core plus a proton structure is assumed for $^{23}$Al. HO-type density distribution is used for the core while the density distribution for the valence proton is calculated by solving the eigenvalue problem of Woods-Saxon potential. The transparency function in an analytical expression is obtained adopting multi-Gaussian expansion for the density distribution. Coulomb correction and finite-range interaction are introduced. This modified Glauber model is apt for halo nuclei. A dominate s-wave is suggested for the last proton in $^{23}$Al from our analysis which is possible in the RMF calculation.

D. Q. Fang; C. W. Ma; Y. G. Ma; X. Z. Cai; J. G. Chen; J. H. Chen; W. Guo; W. D. Tian; K. Wang; Y. B. Wei; T. Z. Yan; C. Zhong; J. X. Zuo; W. Q. Shen

2005-03-10T23:59:59.000Z

251

Domain wall model in the galactic Bose-Einstein condensate halo  

SciTech Connect

We assume that the galactic dark matter halo, considered composed of an axionlike particles Bose-Einstein condensate [1], can present topological defects, namely domain walls, arising as the dark soliton solution for the Gross-Pitaevskii equation in a self-graviting potential. We investigate the influence that such substructures would have in the gravitational interactions within a galaxy. We find that, for the simple domain wall model proposed, the effects are too small to be identified, either by means of a local measurement of the gradient of the gravitational field or by analysing galaxy rotation curves. In the first case, the gradient of the gravitational field in the vicinity of the domain wall would be 10{sup ?31} (m/s{sup 2})/m. In the second case, the ratio of the tangential velocity correction of a star due to the presence of the domain wall to the velocity in the spherical symmetric case would be 10{sup ?8}.

Souza, J.C.C. de; Pires, M.O.C., E-mail: jose.souza@ufabc.edu.br, E-mail: marcelo.pires@ufabc.edu.br [Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adélia 166, 09210-170, Santo André, SP (Brazil)

2013-05-01T23:59:59.000Z

252

Metal and metal-free photocatalysts: mechanistic approach and application as  

E-Print Network (OSTI)

.g., household fluorescence or LED bulbs, halogen lamps, sunlight, Xe lamp), e.g., enantioselective alkylation.lalevee@uha.fr * Corresponding author Keywords: LEDs; photoinitiators; photopolymerization; photoredox catalysis Beilstein J. Org

Boyer, Edmond

253

TURBULENCE AND RADIO MINI-HALOS IN THE SLOSHING CORES OF GALAXY CLUSTERS  

SciTech Connect

A number of relaxed, cool-core galaxy clusters exhibit diffuse, steep-spectrum radio sources in their central regions, known as radio mini-halos. It has been proposed that the relativistic electrons responsible for the emission have been reaccelerated by turbulence generated by the sloshing of the cool core gas. We present a high-resolution MHD simulation of gas sloshing in a galaxy cluster coupled with subgrid simulations of relativistic electron acceleration to test this hypothesis. Our simulation shows that the sloshing motions generate turbulence on the order of {delta}v {approx} 50-200 km s{sup -1} on spatial scales of {approx}50-100 kpc and below in the cool core region within the envelope of the sloshing cold fronts, whereas outside the cold fronts, there is negligible turbulence. This turbulence is potentially strong enough to reaccelerate relativistic electron seeds (with initial {gamma} {approx} 100-500) to {gamma} {approx} 10{sup 4} via damping of magnetosonic waves and non-resonant compression. The seed electrons could remain in the cluster from, e.g., past active galactic nucleus activity. In combination with the magnetic field amplification in the core, these electrons then produce diffuse radio synchrotron emission that is coincident with the region bounded by the sloshing cold fronts, as indeed observed in X-rays and the radio. The result holds for different initial spatial distributions of pre-existing relativistic electrons. The power and the steep spectral index ({alpha} Almost-Equal-To 1-2) of the resulting radio emission are consistent with observations of mini-halos, though the theoretical uncertainties of the acceleration mechanisms are high. We also produce simulated maps of inverse-Compton hard X-ray emission from the same population of relativistic electrons.

ZuHone, J. A.; Markevitch, M. [Astrophysics Science Division, Laboratory for High Energy Astrophysics, Code 662, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States)] [Astrophysics Science Division, Laboratory for High Energy Astrophysics, Code 662, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Brunetti, G. [INAF Istituto di Radioastronomia, Via Gobetti 101, I-40129 Bologna (Italy)] [INAF Istituto di Radioastronomia, Via Gobetti 101, I-40129 Bologna (Italy); Giacintucci, S. [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States)] [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States)

2013-01-10T23:59:59.000Z

254

THE HALO MASS FUNCTION FROM EXCURSION SET THEORY. III. NON-GAUSSIAN FLUCTUATIONS  

SciTech Connect

We compute the effect of primordial non-Gaussianity on the halo mass function, using excursion set theory. In the presence of non-Gaussianity, the stochastic evolution of the smoothed density field, as a function of the smoothing scale, is non-Markovian and beside 'local' terms that generalize Press-Schechter (PS) theory, there are also 'memory' terms, whose effect on the mass function can be computed using the formalism developed in the first paper of this series. We find that, when computing the effect of the three-point correlator on the mass function, a PS-like approach which consists in neglecting the cloud-in-cloud problem and in multiplying the final result by a fudge factor {approx_equal}2, is in principle not justified. When computed correctly in the framework of excursion set theory, in fact, the 'local' contribution vanishes (for all odd-point correlators the contribution of the image Gaussian cancels the PS contribution rather than adding up), and the result comes entirely from non-trivial memory terms which are absent in PS theory. However it turns out that, in the limit of large halo masses, where the effect of non-Gaussianity is more relevant, these memory terms give a contribution which is the same as that computed naively with PS theory, plus subleading terms depending on derivatives of the three-point correlator. We finally combine these results with the diffusive barrier model developed in the second paper of this series, and we find that the resulting mass function reproduces recent N-body simulations with non-Gaussian initial conditions, without the introduction of any ad hoc parameter.

Maggiore, Michele [Departement de Physique Theorique, Universite de Geneve, 24 quai Ansermet, CH-1211 Geneve (Switzerland); Riotto, Antonio [CERN, PH-TH Division, CH-1211, Geneve 23 (Switzerland)

2010-07-01T23:59:59.000Z

255

Metal enriched gaseous halos around distant radio galaxies: Clues to feedback in galaxy formation  

SciTech Connect

We present the results of an optical and near-IR spectroscopic study of giant nebular emission line halos associated with three z > 3 radio galaxies, 4C 41.17, 4C 60.07 and B2 0902+34. Previous deep narrow band Ly{alpha} imaging had revealed complex morphologies with sizes up to 100 kpc, possibly connected to outflows and AGN feedback from the central regions. The outer regions of these halos show quiet kinematics with typical velocity dispersions of a few hundred km s{sup -1}, and velocity shears that can mostly be interpreted as being due to rotation. The inner regions show shocked cocoons of gas closely associated with the radio lobes. These display disturbed kinematics and have expansion velocities and/or velocity dispersions >1000 km s{sup -1}. The core region is chemically evolved, and we also find spectroscopic evidence for the ejection of enriched material in 4C 41.17 up to a distance of {approx} 60 kpc along the radio-axis. The dynamical structures traced in the Ly{alpha} line are, in most cases, closely echoed in the Carbon and Oxygen lines. This shows that the Ly{alpha} line is produced in a highly clumped medium of small filling factor, and can therefore be used as a tracer of the dynamics of HzRGs. We conclude that these HzRGs are undergoing a final jet-induced phase of star formation with ejection of most of their interstellar medium before becoming 'red and dead' Elliptical galaxies.

Reuland, M; van Breugel, W; de Vries, W; Dopita, A; Dey, A; Miley, G; Rottgering, H; Venemans, B; Stanford, S A; Lacy, M; Spinrad, H; Dawson, S; Stern, D; Bunker, A

2006-08-01T23:59:59.000Z

256

INTERNAL STELLAR KINEMATICS OF M32 FROM THE SPLASH SURVEY: DARK HALO CONSTRAINTS  

SciTech Connect

As part of the SPLASH survey of the Andromeda (M31) system, we have obtained Keck/DEIMOS spectra of the compact elliptical (cE) satellite M32. This is the first resolved-star kinematical study of any cE galaxy. In contrast to most previous kinematical studies that extended out to r {approx}< 30'' {approx} 1 r {sup eff} {sub I} {approx} 100 pc, we measure the rotation curve and velocity dispersion profile out to r {approx} 250'' and higher order Gauss-Hermite moments out to r {approx} 70''. We achieve this by combining integrated-light spectroscopy at small radii (where crowding/blending are severe) with resolved stellar spectroscopy at larger radii, using spatial and kinematical information to account statistically for M31 contamination. The rotation curve and velocity dispersion profile extend well beyond the radius (r {approx} 150'') where the isophotes are distorted. Unlike NGC 205, another close dwarf companion of M31, M32's kinematics appear regular and symmetric and do not show obvious sharp gradients across the region of isophotal elongation and twists. We interpret M31's kinematics using three-integral axisymmetric dynamical equilibrium models constructed using Schwarzschild's orbit superposition technique. Models with a constant mass-to-light ratio can fit the data remarkably well. However, since such a model requires an increasing tangential anisotropy with radius, invoking the presence of an extended dark halo may be more plausible. Such an extended dark halo is definitely required to bind a half-dozen fast-moving stars observed at the largest radii, but these stars may not be an equilibrium component of M32.

Howley, K. M. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551 (United States)] [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551 (United States); Guhathakurta, P. [UCO/Lick Observatory, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States)] [UCO/Lick Observatory, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Van der Marel, R.; Kalirai, J. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)] [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Geha, M. [Department of Astronomy, Yale University, New Haven, CT 06510 (United States)] [Department of Astronomy, Yale University, New Haven, CT 06510 (United States); Yniguez, B. [Physics and Astronomy Department, University of California, Irvine, 4129 Frederick Reines Hall, Irvine, CA 92697 (United States)] [Physics and Astronomy Department, University of California, Irvine, 4129 Frederick Reines Hall, Irvine, CA 92697 (United States); Kirby, E. [Department of Astronomy, California Institute of Technology, 1200 East California Blvd, Pasadena, CA 91125 (United States)] [Department of Astronomy, California Institute of Technology, 1200 East California Blvd, Pasadena, CA 91125 (United States); Cuillandre, J.-C. [Canada-France-Hawaii Telescope, 65-1238 Mamalahoa Hwy, Kamuela, HI 96743 (United States)] [Canada-France-Hawaii Telescope, 65-1238 Mamalahoa Hwy, Kamuela, HI 96743 (United States); Gilbert, K., E-mail: howley1@llnl.gov, E-mail: raja@ucolick.org, E-mail: marel@stsci.edu, E-mail: jkalirai@stsci.edu, E-mail: marla.geha@yale.edu, E-mail: byniguez@uci.edu, E-mail: enk@astro.caltech.edu, E-mail: jcc@cfht.hawaii.edu, E-mail: kgilbert@astro.washington.edu [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States)

2013-03-01T23:59:59.000Z

257

Discussion on the energy content of the galactic dark matter Bose-Einstein condensate halo in the Thomas-Fermi approximation  

E-Print Network (OSTI)

We show that the galactic dark matter halo, considered composed of an axionlike particles Bose-Einstein condensate \\cite{pir12} trapped by a self-graviting potential \\cite{boh07}, may be stable in the Thomas-Fermi approximation since appropriate choices for the dark matter particle mass and scattering length are made. The demonstration is performed by means of the calculation of the potential, kinetic and self-interaction energy terms of a galactic halo described by a Boehmer-Harko density profile. We discuss the validity of the Thomas-Fermi approximation for the halo system, and show that the kinetic energy contribution is indeed negligible.

J. C. C. de Souza; M. O. C. Pires

2014-01-23T23:59:59.000Z

258

The spatial distribution of organochlorine pesticides and halogenated flame retardants in the surface sediments of an Arctic fjord: The influence of ocean currents vs. glacial runoff  

Science Journals Connector (OSTI)

Abstract Selected organochlorine pesticides (OCs) and halogenated flame retardants (HFRs) were analyzed in surficial fjord sediments collected down the length of Kongsfjorden, Svalbard in the Norwegian high Arctic. Hexachlorocyclohexane (?-HCHs) was found to be the most abundant OC in the sediment, followed by BDE-209 > chlordane > ?-endosulfan > Dechlorane Plus (anti-DP)> trifluralin concentration ranges were high over the relatively small study area of the fjord (e.g. ?HCH: 7.2–100 pg g?1 dry weight (dw)), with concentrations broadly similar to, or lower than, measurements conducted in other parts of the Arctic. Concentrations of legacy OCs, including both HCH isomers and chlordane showed a decreasing trend from the outer, seaward end of the fjord to the inner, glacier end of the fjord. Conversely, sediment concentrations of ?- and ?-endosulfan (0.1–12.5 pg g?1 dw) increased from the outer fjord to the inner fjord. This contrasting pattern may be attributed to the influence of historical vs. contemporary sources of these chemicals to the fjord area, whereby the North Atlantic/West Spitzbergen oceanic current dominates the transport and input of the legacy OCs, whereas atmospheric deposition and meltwater runoff from the glaciers influence the inner fjord sediments for endosulfan. Interestingly, BDE-209 and Dechlorane Plus did not reveal any clear spatial trend. It is plausible that both glacial runoff and oceanic current end members are playing a role in introducing these chemicals to the fjord sediments. The relatively low fractional abundance of the syn-DP isomer (fsyn), however, indicates the long-range transport of this chemical to this Arctic site.

Yuxin Ma; Zhiyong Xie; Crispin Halsall; Axel Möller; Haizhen Yang; Guangcai Zhong; Minghong Cai; Ralf Ebinghaus

2015-01-01T23:59:59.000Z

259

Secondary infall model of galactic halo formation and the spectrum of cold dark matter particles on Earth  

Science Journals Connector (OSTI)

The spectrum of cold dark matter particles on Earth is expected to have peaks in velocity space associated with particles which are falling onto the Galaxy for the first time and with particles which have fallen in and out of the Galaxy only a small number of times in the past. We obtain estimates for the velocity magnitudes and the local densities of the particles in these peaks. To this end we use the secondary infall model of galactic halo formation which we have generalized to take account of the angular momentum of the dark matter particles. The new model is still spherically symmetric and it admits self-similar solutions. In the absence of angular momentum, the model produces flat rotation curves for a large range of values of a parameter ? which is related to the spectrum of primordial density perturbations. We find that the presence of angular momentum produces an effective core radius; i.e., it makes the contribution of the halo to the rotation curve go to zero at zero radius. The model provides a detailed description of the large scale properties of galactic halos including their density profiles, their extent, and total mass. We obtain predictions for the kinetic energies of the particles in the velocity peaks and estimates for their local densities as functions of the amount of angular momentum, the age of the Universe, and ?.

P. Sikivie; I. I. Tkachev; Yun Wang

1997-08-15T23:59:59.000Z

260

Cryogenic ion implantation near amorphization threshold dose for halo/extension junction improvement in sub-30 nm device technologies  

SciTech Connect

We report on junction advantages of cryogenic ion implantation with medium current implanters. We propose a methodical approach on maximizing cryogenic effects on junction characteristics near the amorphization threshold doses that are typically used for halo implants for sub-30 nm technologies. BF{sub 2}{sup +} implant at a dose of 8 Multiplication-Sign 10{sup 13}cm{sup -2} does not amorphize silicon at room temperature. When implanted at -100 Degree-Sign C, it forms a 30 - 35 nm thick amorphous layer. The cryogenic BF{sub 2}{sup +} implant significantly reduces the depth of the boron distribution, both as-implanted and after anneals, which improves short channel rolloff characteristics. It also creates a shallower n{sup +}-p junction by steepening profiles of arsenic that is subsequently implanted in the surface region. We demonstrate effects of implant sequences, germanium preamorphization, indium and carbon co-implants for extension/halo process integration. When applied to sequences such as Ge+As+C+In+BF{sub 2}{sup +}, the cryogenic implants at -100 Degree-Sign C enable removal of Ge preamorphization, and form more active n{sup +}-p junctions and steeper B and In halo profiles than sequences at room temperature.

Park, Hugh; Todorov, Stan; Colombeau, Benjamin; Rodier, Dennis; Kouzminov, Dimitry; Zou Wei; Guo Baonian; Khasgiwale, Niranjan; Decker-Lucke, Kurt [Applied Materials, Varian Semiconductor Equipment, 35 Dory Road, Gloucester, Massachusetts 01930 (United States)

2012-11-06T23:59:59.000Z

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
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261

Neutron-halo nuclei in cold synthesis and cluster decay of heavy nuclei: Z=104 nucleus as an example  

Science Journals Connector (OSTI)

Nuclei at the neutron-drip line are studied. The light neutron-halo nuclei are found to play an important role for both cold fusion reactions and exotic cluster decay studies of heavy nuclei at the neutron-drip line. For cold fusion reactions, beams of neutron-halo nuclei are shown to occur as natural extensions of the conventional lighter beams but with the corresponding target nuclei as the heavy neutron-rich radioactive nuclei. Thus, in synthesizing the various isotopes of a neutron-rich cool compound nucleus, both the target and projectile nuclei have to be richer in neutrons, with their proton numbers remaining the same. On the other hand, neutron-halo (cluster) decays are favored for a relatively less neutron-rich parent nucleus. Possible consequences of this work for the shell structure effects in neutron-rich heavy nuclei are also pointed out. This follows from the fact that the so far observed phenomena of both cold fusion and cluster radioactivity are associated with closed or nearly closed shell nuclei. Calculations are made for 104274,288, using the quantum mechanical fragmentation theory for cold fusion reaction studies and a performed cluster model for cluster decay studies.

Raj K. Gupta; Sarbjit Singh; Gottfried Münzenberg; Werner Scheid

1995-05-01T23:59:59.000Z

262

The accretion history of dark matter halos III: A physical model for the concentration-mass relation  

E-Print Network (OSTI)

We present a semi-analytic, physically motivated model for dark matter halo concentration as a function of halo mass and redshift. The semi-analytic model is intimately based on hierarchical structure formation. It uses an analytic model for the halo mass accretion history, based on extended Press Schechter (EPS) theory, and an empirical relation between concentration and an appropriate definition of formation time obtained through fits to the results of numerical simulations. The resulting concentration-mass relations are tested against the simulations and do not exhibit an upturn at high masses or high redshifts as claimed by recent works. Because our semi-analytic model is based on EPS theory, it can be applied to wide ranges in mass, redshift and cosmology. We predict a change of slope in the z=0 concentration-mass relation at a mass scale of $10^{11}\\rm{M}_{\\odot}$, that is caused by the varying power in the density perturbations. We provide best-fitting expressions of the $c-M$ relations as well as nume...

Correa, Camila A; Schaye, Joop; Duffy, Alan R

2015-01-01T23:59:59.000Z

263

Quantifying the heart of darkness with GHALO - a multi-billion particle simulation of our galactic halo  

E-Print Network (OSTI)

We perform a series of simulations of a Galactic mass dark matter halo at different resolutions, our largest uses over three billion particles and has a mass resolution of 1000 M_sun. We quantify the structural properties of the inner dark matter distribution and study how they depend on numerical resolution. We can measure the density profile to a distance of 120 pc (0.05% of R_vir) where the logarithmic slope is -0.8 and -1.4 at (0.5% of R_vir). We propose a new two parameter fitting function that has a linearly varying logarithmic density gradient which fits the GHALO and VL2 density profiles extremely well. Convergence in the density profile and the halo shape scales as N^(-1/3), but the shape converges at a radius three times larger at which point the halo becomes more spherical due to numerical resolution. The six dimensional phase-space profile is dominated by the presence of the substructures and does not follow a power law, except in the smooth under-resolved inner few kpc.

Joachim Stadel; Doug Potter; Ben Moore; Jürg Diemand; Piero Madau; Marcel Zemp; Michael Kuhlen; Vicent Quilis

2008-08-22T23:59:59.000Z

264

Updated 9/23/2010 HOW TO RECYCLE  

E-Print Network (OSTI)

/Copiers · Garbage · Gas Cylinders · Glass Bottles & Jars · Grease · Halogen Bulbs · Hardbound Books · Hazardous Waste · Helium Tanks · Imaging Units for Printers/Copiers · Incandescent Bulbs · Ink Jet Printer · Newspapers & Newsprint #12;Updated 9/23/2010 · Office Supplies · Oil · Packing Peanuts · Paint · Pallets

Clark, John

265

Working Paper Sustainability and Innovation No. S 3/2014  

E-Print Network (OSTI)

efficient compact fluorescent lamps (CFLs) or light emitting diodes (LEDs) using a large nationally rebound effects associated with the switch from incandescent lamps (ILs) or halogen bulbs to more energy is decomposed into changes in lamp luminosity and burn time. On average, more efficient replace- ment bulbs

Paris-Sud XI, Université de

266

Qualitative and analytical results of the bifurcation thresholds to halo orbits  

E-Print Network (OSTI)

We study the dynamics in the neighborhood of the collinear Lagrangian points in the spatial, circular, restricted three--body problem. We consider the case in which one of the primaries is a radiating body and the other is oblate (although the latter is a minor effect). Beside having an intrinsic mathematical interest, this model is particularly suited for the description of a mission of a spacecraft (e.g., a solar sail) to an asteroid. The aim of our study is to investigate the occurrence of bifurcations to halo orbits, which take place as the energy level is varied. The estimate of the bifurcation thresholds is performed by analytical and numerical methods: we find a remarkable agreement between the two approaches. As a side result, we also evaluate the influence of the different parameters, most notably the solar radiation pressure coefficient, on the dynamical behavior of the model. To perform the analytical and numerical computations, we start by implementing a center manifold reduction. Next, we estimate the bifurcation values using qualitative techniques (e.g. Poincar\\'e surfaces, frequency analysis, FLIs). Concerning the analytical approach, following \\cite{CPS} we implement a resonant normal form, we transform to suitable action-angle variables and we introduce a detuning parameter measuring the displacement from the synchronous resonance. The bifurcation thresholds are then determined as series expansions in the detuning. Three concrete examples are considered and we find in all cases a very good agreement between the analytical and numerical results.

Sara Bucciarelli; Marta Ceccaroni; Alessandra Celletti; Giuseppe Pucacco

2015-02-01T23:59:59.000Z

267

Bar-Halo Friction in Galaxies III: Particle Number Requirements for Simulations  

E-Print Network (OSTI)

The question whether the dark matter halo density in the centers of galaxies could be changed through interactions with a rotating bar in the baryonic disk is of considerable current interest. While N-body simulations have been used to address this question, it has also been claimed that results from such simulations cannot be trusted. Based on a perturbative treatment of resonant exchanges between orbits and a rotating perturbation, Weinberg & Katz contend that N-body simulations of this process will not reveal the continuum result unless many more than the usual numbers of particles are employed. Here I report a study designed to examine their contention, finding results that show no dependence on the number of particles over the range usually employed up to that advocated by these authors. I show that my results are independent of all numerical parameters, and that field methods perform equally with grid methods in this respect. I also identify the reasons that the required particle number suggested by Weinberg & Katz is excessive.

J. A. Sellwood

2007-04-08T23:59:59.000Z

268

Qualitative and analytical results of the bifurcanion thresholds to halo orbits  

E-Print Network (OSTI)

We study the dynamics in the neighborhood of the collinear Lagrangian points in the spatial, circular, restricted three--body problem. We consider the case in which one of the primaries is a radiating body and the other is oblate (although the latter is a minor effect). Beside having an intrinsic mathematical interest, this model is particularly suited for the description of a mission of a spacecraft (e.g., a solar sail) to an asteroid. The aim of our study is to investigate the occurrence of bifurcations to halo orbits, which take place as the energy level is varied. The estimate of the bifurcation thresholds is performed by analytical and numerical methods: we find a remarkable agreement between the two approaches. As a side result, we also evaluate the influence of the different parameters, most notably the solar radiation pressure coefficient, on the dynamical behavior of the model. To perform the analytical and numerical computations, we start by implementing a center manifold reduction. Next, we estimate the bifurcation values using qualitative techniques (e.g. Poincar\\'e surfaces, frequency analysis, FLIs). Concerning the analytical approach, following \\cite{CPS} we implement a resonant normal form, we transform to suitable action-angle variables and we introduce a detuning parameter measuring the displacement from the synchronous resonance. The bifurcation thresholds are then determined as series expansions in the detuning. Three concrete examples are considered and we find in all cases a very good agreement between the analytical and numerical results.

Sara Bucciarelli; Marta Ceccaroni; Alessandra Celletti; Giuseppe Pucacco

2015-01-23T23:59:59.000Z

269

Rotation Curve with MOND and Dark Matter Halo profile for ESO138-G014  

E-Print Network (OSTI)

This paper is devoted to solve the galactic rotation problem for ESO138-G014 galaxy based on two theories: dark matter and Modified Newtonian Dynamics. Here we did the rotation curve analysis with two possible choices for the dark matter density profile, namely Burkert and Navarro, Frenk and White profiles. The analysis shows the dark matter distribution favored to Burkert profile (cored dark matter). The standard hypothesis for most spiral galaxies are known to be embedded in dark matter haloes has now been overshadowed by Modified Newtonian Dynamics, known as MOND, the leading alternative of dark matter. MOND addresses the problem of a new fundamental constant $a_0$, called the acceleration constant, at which acceleration scale of Newton second law fails to hold. In this respect, we investigate this issue by testing the rotation curve within the MOND framework with the observations to obtain the reliable disk mass, $M_D$. We investigate whether ESO138-G014 is compatible with MOND or dark matter is still favorable for the galactic rotation problem.

Norsiah Hashim; Mariafelicia De Laurentis; Zamri Zainal Abidin; Paolo Salucci

2014-07-01T23:59:59.000Z

270

A PECULIAR FAINT SATELLITE IN THE REMOTE OUTER HALO OF M31  

SciTech Connect

We present Hubble Space Telescope imaging of a newly discovered faint stellar system, PAndAS-48, in the outskirts of the M31 halo. Our photometry reveals this object to be comprised of an ancient and very metal-poor stellar population with age {approx}> 10 Gyr and [Fe/H] {approx}< -2.3. Our inferred distance modulus (m - M){sub 0} = 24.57 {+-} 0.11 confirms that PAndAS-48 is most likely a remote M31 satellite with a three-dimensional galactocentric radius of 149{sup +19}{sub -8} kpc. We observe an apparent spread in color on the upper red giant branch that is larger than the photometric uncertainties should allow, and briefly explore the implications of this. Structurally, PAndAS-48 is diffuse, faint, and moderately flattened, with a half-light radius r{sub h}=26{sup +4}{sub -3} pc, integrated luminosity M{sub V} = -4.8 {+-} 0.5, and ellipticity {epsilon}=0.30{sup +0.08}{sub -0.15}. On the size-luminosity plane it falls between the extended globular clusters seen in several nearby galaxies and the recently discovered faint dwarf satellites of the Milky Way; however, its characteristics do not allow us to unambiguously classify it as either type of system. If PAndAS-48 is a globular cluster then it is among the most elliptical, isolated, and metal-poor of any seen in the Local Group, extended or otherwise. Conversely, while its properties are generally consistent with those observed for the faint Milky Way dwarfs, it would be a factor of {approx}2-3 smaller in spatial extent than any known counterpart of comparable luminosity.

Mackey, A. D.; Dotter, A. [Research School of Astronomy and Astrophysics, Australian National University, Mount Stromlo Observatory, via Cotter Road, Weston, ACT 2611 (Australia); Huxor, A. P. [Astronomisches Rechen-Institut, Universitaet Heidelberg, Moenchhofstrasse 12-14, D-69120 Heidelberg (Germany); Martin, N. F.; Ibata, R. A. [Observatoire astronomique de Strasbourg, Universite de Strasbourg, CNRS, UMR 7550, 11 rue de l'Universite, F-67000 Strasbourg (France); Ferguson, A. M. N. [Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); McConnachie, A. W. [NRC Herzberg Institute for Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Irwin, M. J. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Lewis, G. F. [Sydney Institute for Astronomy, School of Physics, A28, University of Sydney, NSW 2006 (Australia); Sakari, C. M.; Venn, K. A. [Department of Physics and Astronomy, University of Victoria, 3800 Finnerty Road, Victoria, BC V8P 1A1 (Canada); Tanvir, N. R., E-mail: dougal@mso.anu.edu.au [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom)

2013-06-20T23:59:59.000Z

271

EXTENDED HOT HALOS AROUND ISOLATED GALAXIES OBSERVED IN THE ROSAT ALL-SKY SURVEY  

SciTech Connect

We place general constraints on the luminosity and mass of hot X-ray-emitting gas residing in extended 'hot halos' around nearby massive galaxies. We examine stacked images of 2165 galaxies from the 2MASS Isolated Galaxy Catalog as well as subsets of this sample based on galaxy morphology and K-band luminosity. We detect X-ray emission at high confidence (ranging up to nearly 10{sigma}) for each subsample of galaxies. The average L{sub X} within 50 kpc is 1.0 {+-} 0.1 (statistical) {+-}0.2 (systematic) Multiplication-Sign 10{sup 40} erg s{sup -1}, although the early-type galaxies are more than twice as luminous as the late-type galaxies. Using a spatial analysis, we also find evidence for extended emission around five out of seven subsamples (the full sample, the luminous galaxies, early-type galaxies, luminous late-type galaxies, and luminous early-type galaxies) at 92.7%, 99.3%, 89.3%, 98.7%, and 92.1% confidence, respectively. Several additional lines of evidence also support this conclusion and suggest that about 1/2 of the total emission is extended, and about 1/3 of the extended emission comes from hot gas. For the sample of luminous galaxies, which has the strongest evidence for extended emission, the average hot gas mass is 4 Multiplication-Sign 10{sup 9} M {sub Sun} within 50 kpc and the implied accretion rate is 0.4 M {sub Sun} yr{sup -1}.

Anderson, Michael E.; Bregman, Joel N. [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States)] [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States); Dai, Xinyu, E-mail: michevan@umich.edu, E-mail: jbregman@umich.edu, E-mail: xdai@ou.edu [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States)] [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States)

2013-01-10T23:59:59.000Z

272

Strong Gravitational Lensing Time Delay Statistics and the Density Profile of Dark Halos  

Science Journals Connector (OSTI)

The distribution of differential time delays ?t between images produced by strong gravitational lensing contains information on the mass distributions in the lensing objects as well as on cosmological parameters such as H0. We derive an explicit expression for the conditional probability distribution function of time delays P(?t | ?), given an image separation between multiple images ? and related statistics. We consider lensing halos described by the singular isothermal sphere (SIS) approximation and by its generalization as proposed by Navarro, Frenk, & White (NFW), which has a density profile ? ? r-? in the innermost region. The time delay distribution is very sensitive to these profiles; steeper inner slopes tend to produce larger time delays. For example, if H0 = 70 km s-1 Mpc-1, a ?-dominated cosmology and a source redshift zS = 1.27 are assumed, lenses with ? = 5'' produce a time delay of ?t = 1.5, 0.39, 0.15, and 0.071 yr (50% confidence interval) for SIS, generalized NFW with ? = 1.5, ? = 1.0, and ? = 0.5, respectively. At a fixed image separation, the time delay is determined by the difference in the lensing potential between the position of the two images, which typically occur at different impact parameters. Although the values of ?t are proportional to the inverse of H0, P(?t | ?) is rather insensitive to all other cosmological model parameters, source redshifts, magnification biases, and so on. A knowledge of P(?t | ?) will also be useful in designing the observing program of future large-scale synoptic variability surveys and for evaluating possible selection biases operating against large splitting lens systems.

Masamune Oguri; Atsushi Taruya; Yasushi Suto; Edwin L. Turner

2002-01-01T23:59:59.000Z

273

The dark haloes of early-type galaxies in low-density environments: XMM-Newton and Chandra observations of NGC 57, NGC 7796 and IC 1531  

E-Print Network (OSTI)

We present analysis of Chandra and XMM-Newton observations of three early-type galaxies, NGC 57, NGC 7796 and IC 1531. All three are found in very low density environments, and appear to have no neighbours of comparable size. NGC 57 has a halo of kT~0.9 keV, solar metallicity gas, while NGC 7796 and IC 1531 both have ~0.55 keV, 0.5-0.6 Zsol haloes. IC 1531 has a relatively compact halo, and we consider it likely that gas has been removed from the system by the effects of AGN heating. For NGC 57 and NGC 7796 we estimate mass, entropy and cooling time profiles and find that NGC 57 has a fairly massive dark halo with a mass-to-light ratio of 44.7 (4.0,-8.5) Msol/Lsol (1 sigma uncertainties) at 4.75 Re. This is very similar to the mass-to-light ratio found for NGC 4555 and confirms that isolated ellipticals can possess sizable dark matter haloes. We find a significantly lower mass-to-light ratio for NGC 7796, 10.6 (+2.5,-2.3) Msol/Lsol at 5 Re, and discuss the possibility that NGC 7796 hosts a galactic wind, causing us to underestimate its mass.

E. O'Sullivan; A. J. R. Sanderson; T. J. Ponman

2007-07-12T23:59:59.000Z

274

SEARCHING FOR NEUTRAL HYDROGEN HALOS AROUND z ? 2.1 AND z ? 3.1 Ly? EMITTING GALAXIES  

SciTech Connect

We search for evidence of diffuse Ly? emission from extended neutral hydrogen surrounding Ly? emitting galaxies (LAEs) using deep narrow-band images of the Extended Chandra Deep Field South. By stacking the profiles of 187 LAEs at z = 2.06, 241 LAEs at z = 3.10, and 179 LAEs at z = 3.12, and carefully performing low-surface brightness photometry, we obtain mean surface brightness maps that reach 9.9, 8.7, and 6.2 × 10{sup –19} erg cm{sup –2} s{sup –1} arcsec{sup –2} in the emission line. We undertake a thorough investigation of systematic uncertainties in our surface brightness measurements and find that our limits are 5-10 times larger than would be expected from Poisson background fluctuations; these uncertainties are often underestimated in the literature. At z ? 3.1, we find evidence for extended halos with small-scale lengths of 5-8 kpc in some but not all of our sub-samples. We demonstrate that sub-samples of LAEs with low equivalent widths and brighter continuum magnitudes are more likely to possess such halos. At z ? 2.1, we find no evidence of extended Ly? emission down to our detection limits. Through Monte-Carlo simulations, we also show that we would have detected large diffuse LAE halos if they were present in our data sets. We compare these findings to other measurements in the literature and discuss possible instrumental and astrophysical reasons for the discrepancies.

Feldmeier, John J. [Department of Physics and Astronomy, Youngstown State University, Youngstown, OH 44555 (United States); Hagen, Alex; Ciardullo, Robin; Gronwall, Caryl; Hagen, Lea M. Z. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Gawiser, Eric; Kurczynski, Peter [Department of Physics and Astronomy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854 (United States); Guaita, Lucia [Oskar Klein Cosmology Centre, Department of Astronomy, Stockholm University, SE-106 91 Stolkholm (Sweden); Bond, Nicholas A. [Cosmology Laboratory (Code 665), NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Acquaviva, Viviana [Department of Physics, New York City College of Technology, City University of New York, 300 Jay Street, Brooklyn, NY 11201 (United States); Blanc, Guillermo A. [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Orsi, Alvaro, E-mail: jjfeldmeier@ysu.edu [Departamento de Astronomía y Astrofísica, Pontificia Universidad Católica, Av. Vicuña Mackenna 4860, Santiago (Chile)

2013-10-20T23:59:59.000Z

275

THE YOUNG OPEN CLUSTERS KING 12, NGC 7788, AND NGC 7790: PRE-MAIN-SEQUENCE STARS AND EXTENDED STELLAR HALOS  

SciTech Connect

The stellar contents of the open clusters King 12, NGC 7788, and NGC 7790 are investigated using MegaCam images. Comparisons with isochrones yield an age <20 Myr for King 12, 20-40 Myr for NGC 7788, and 60-80 Myr for NGC 7790 based on the properties of stars near the main-sequence turnoff (MSTO) in each cluster. The reddening of NGC 7788 is much larger than previously estimated. The luminosity functions (LFs) of King 12 and NGC 7788 show breaks that are attributed to the onset of pre-main-sequence (PMS) objects, and comparisons with models of PMS evolution yield ages that are consistent with those measured from stars near the MSTO. In contrast, the r' LF of main-sequence stars in NGC 7790 is matched to r' = 20 by a model that is based on the solar neighborhood mass function. The structural properties of all three clusters are investigated by examining the two-point angular correlation function of blue main-sequence stars. King 12 and NGC 7788 are each surrounded by a stellar halo that extends out to a radius of 5 arcmin ({approx}3.4 pc). It is suggested that these halos form in response to large-scale mass ejection early in the evolution of the clusters, as predicted by models. In contrast, blue main-sequence stars in NGC 7790 are traced out to a radius of {approx}7.5 arcmin ({approx}5.5 pc), with no evidence of a halo. It is suggested that all three clusters may have originated in the same star-forming complex, but not in the same giant molecular cloud.

Davidge, T. J. [Dominion Astrophysical Observatory, National Research Council of Canada, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada)

2012-12-20T23:59:59.000Z

276

OXYGEN ABUNDANCES IN LOW- AND HIGH-{alpha} FIELD HALO STARS AND THE DISCOVERY OF TWO FIELD STARS BORN IN GLOBULAR CLUSTERS  

SciTech Connect

Oxygen abundances of 67 dwarf stars in the metallicity range -1.6 < [Fe/H] < -0.4 are derived from a non-LTE analysis of the 777 nm O I triplet lines. These stars have precise atmospheric parameters measured by Nissen and Schuster, who find that they separate into three groups based on their kinematics and {alpha}-element (Mg, Si, Ca, Ti) abundances: thick disk, high-{alpha} halo, and low-{alpha} halo. We find the oxygen abundance trends of thick-disk and high-{alpha} halo stars very similar. The low-{alpha} stars show a larger star-to-star scatter in [O/Fe] at a given [Fe/H] and have systematically lower oxygen abundances compared to the other two groups. Thus, we find the behavior of oxygen abundances in these groups of stars similar to that of the {alpha} elements. We use previously published oxygen abundance data of disk and very metal-poor halo stars to present an overall view (-2.3 < [Fe/H] < +0.3) of oxygen abundance trends of stars in the solar neighborhood. Two field halo dwarf stars stand out in their O and Na abundances. Both G53-41 and G150-40 have very low oxygen and very high sodium abundances, which are key signatures of the abundance anomalies observed in globular cluster (GC) stars. Therefore, they are likely field halo stars born in GCs. If true, we estimate that at least 3% {+-} 2% of the local field metal-poor star population was born in GCs.

Ramirez, I. [McDonald Observatory and Department of Astronomy, University of Texas at Austin, 1 University Station, C1400 Austin, TX 78712-0259 (United States); Melendez, J. [Departamento de Astronomia do IAG/USP, Universidade de Sao Paulo, Rua do Matao 1226, Sao Paulo 05508-900, SP (Brazil); Chaname, J. [Departamento de Astronomia y Astrofisica, Pontificia Universidad Catolica de Chile, Av. Vicuna Mackenna 4860, 782-0436 Macul, Santiago (Chile)

2012-10-01T23:59:59.000Z

277

Mon. Not. R. Astron. Soc. 410, 210226 (2011) doi:10.1111/j.1365-2966.2010.17436.x Satellite kinematics III. Halo masses of central galaxies in SDSS  

E-Print Network (OSTI)

matter. The fluctuations in the dark matter density field grow under the action of gravity and form a web that orbit around the central galaxy in a dark matter halo to infer the scaling relations between halo mass of 2), indicating that we are converging on an accurate and reliable description of the galaxy­dark

Skibba, Ramin A.

278

Study of beam optics and beam halo by integrated modeling of negative ion beams from plasma meniscus formation to beam acceleration  

SciTech Connect

To understand the physical mechanism of the beam halo formation in negative ion beams, a two-dimensional particle-in-cell code for simulating the trajectories of negative ions created via surface production has been developed. The simulation code reproduces a beam halo observed in an actual negative ion beam. The negative ions extracted from the periphery of the plasma meniscus (an electro-static lens in a source plasma) are over-focused in the extractor due to large curvature of the meniscus.

Miyamoto, K. [Naruto University of Education, 748 Nakashima, Takashima, Naruto-cho, Naruto-shi, Tokushima 772-8502 (Japan)] [Naruto University of Education, 748 Nakashima, Takashima, Naruto-cho, Naruto-shi, Tokushima 772-8502 (Japan); Okuda, S.; Hatayama, A. [Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan)] [Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan); Hanada, M.; Kojima, A. [Japan Atomic Energy Agency, 801-1 Mukouyama, Naka 319-0913 (Japan)] [Japan Atomic Energy Agency, 801-1 Mukouyama, Naka 319-0913 (Japan)

2013-01-14T23:59:59.000Z

279

A Model of the EGRET Source at the Galactic Center: Inverse Compton Scattering Within Sgr A East and its Halo  

E-Print Network (OSTI)

Continuum low-frequency radio observations of the Galactic Center reveal the presence of two prominent radio sources, Sgr A East and its surrounding Halo, containing non-thermal particle distributions with power-law indices around 2.5-3.3 and 2.4, respectively. The central 1-2 pc region is also a source of intense (stellar) UV and (dust-reprocessed) far-IR radiation that bathes these extended synchrotron-emitting structures. A recent detection of gamma-rays (2EGJ1746-2852) from within around 1 degree of the Galactic Center by EGRET onboard the Compton GRO shows that the emission from this environment extends to very high energies. We suggest that inverse Compton scatterings between the power-law electrons inferred from the radio properties of Sgr A East and its Halo, and the UV and IR photons from the nucleus, may account for the possibly diffuse gamma-ray source as well. We show that both particle distributions may be contributing to the gamma-ray emission, though their relevant strength depends on the actual physical properties (such as the magnetic field intensity) in each source. If this picture is correct, the high-energy source at the Galactic Center is extended over several arcminutes, which can be tested with thenext generation of gamma-ray and hard X-ray missions.

Fulvio Melia; Farhad Yusef-Zadeh; Marco Fatuzzo

1998-06-24T23:59:59.000Z

280

The Outer Halo of the Nearest Giant Elliptical: A VLT/VIMOS Survey of the Resolved Stellar Populations in Centaurus A to 85 kpc  

E-Print Network (OSTI)

We present the first deep survey of resolved stellar populations in the remote outer halo of our nearest giant elliptical (gE), Centaurus A (D=3.8 Mpc). Using the VIMOS/VLT optical camera, we obtained deep photometry for four fields along the major and minor axes at projected elliptical radii of ~30-85 kpc (corresponding to ~5-14 R_{eff}). We use resolved star counts to map the spatial and colour distribution of red giant branch (RGB) stars down to ~2 magnitudes below the RGB tip. We detect an extended halo out to the furthermost elliptical radius probed (~85 kpc or ~14 R_{eff}), demonstrating the vast extent of this system. We detect a localised substructure in these parts, visible in both (old) RGB and (intermediate-age) luminous asymptotic giant branch stars, and there is some evidence that the outer halo becomes more elliptical and has a shallower surface brightness profile. We derive photometric metallicity distribution functions for halo RGB stars and find relatively high median metallicity values ([Fe/...

Crnojevi?, D; Irwin, M J; Bernard, E J; Arimoto, N; Jablonka, P; Kobayashi, C

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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281

A Lyman-alpha blob in the GOODS South field: evidence for cold accretion onto a dark matter halo  

E-Print Network (OSTI)

We report on the discovery of a z = 3.16 Lyman-alpha emitting blob in the GOODS South field. The blob has a total Ly-alpha luminosity of ~ 10^(43) erg s^(-1) and a diameter larger than 60 kpc. The available multi-wavelength data in the GOODS field consists of 13 bands from X-rays (Chandra) to infrared (Spitzer). Unlike other discovered Ly-alpha blobs, this blob shows no obvious continuum counter-part in any of the broad-bands. In particular, no optical counter-parts are found in the deep HST/ACS imaging available. For previously published blobs, AGN (Active Galactic Nuclei) or 'superwind' models have been found to provide the best match with the data. We here argue that the most probable origin of the extended Ly-alpha emission from the blob in the GOODS South field is cold accretion onto a dark matter halo.

Kim Nilsson; Johan P. U. Fynbo; Palle Moller; Jesper Sommer-Larsen; Cedric Ledoux

2005-12-15T23:59:59.000Z

282

MEASURING THE ULTIMATE HALO MASS OF GALAXY CLUSTERS: REDSHIFTS AND MASS PROFILES FROM THE HECTOSPEC CLUSTER SURVEY (HeCS)  

SciTech Connect

The infall regions of galaxy clusters represent the largest gravitationally bound structures in a {Lambda}CDM universe. Measuring cluster mass profiles into the infall regions provides an estimate of the ultimate mass of these halos. We use the caustic technique to measure cluster mass profiles from galaxy redshifts obtained with the Hectospec Cluster Survey (HeCS), an extensive spectroscopic survey of galaxy clusters with MMT/Hectospec. We survey 58 clusters selected by X-ray flux at 0.1 < z < 0.3. The survey includes 22,680 unique MMT/Hectospec redshifts for individual galaxies; 10,145 of these galaxies are cluster members. For each cluster, we acquired high signal-to-noise spectra for {approx}200 cluster members and a comparable number of foreground/background galaxies. The cluster members trace out infall patterns around the clusters. The members define a very narrow red sequence. We demonstrate that the determination of velocity dispersion is insensitive to the inclusion of bluer members (a small fraction of the cluster population). We apply the caustic technique to define membership and estimate the mass profiles to large radii. The ultimate halo mass of clusters (the mass that remains bound in the far future of a {Lambda}CDM universe) is on average (1.99 {+-} 0.11)M{sub 200}, a new observational cosmological test in essential agreement with simulations. Summed profiles binned in M{sub 200} and in L{sub X} demonstrate that the predicted Navarro-Frenk-White form of the density profile is a remarkably good representation of the data in agreement with weak lensing results extending to large radius. The concentration of these summed profiles is also consistent with theoretical predictions.

Rines, Kenneth [Department of Physics and Astronomy, Western Washington University, Bellingham, WA 98225 (United States)] [Department of Physics and Astronomy, Western Washington University, Bellingham, WA 98225 (United States); Geller, Margaret J.; Kurtz, Michael J. [Smithsonian Astrophysical Observatory, 60 Garden Street, MS 20, Cambridge, MA 02138 (United States)] [Smithsonian Astrophysical Observatory, 60 Garden Street, MS 20, Cambridge, MA 02138 (United States); Diaferio, Antonaldo, E-mail: kenneth.rines@wwu.edu, E-mail: diaferio@ph.unito.it [Dipartimento di Fisica, Universita di Torino, Torino (Italy)] [Dipartimento di Fisica, Universita di Torino, Torino (Italy)

2013-04-10T23:59:59.000Z

283

Ceramic Mugs & Dishes Incandescent Light Bulbs  

E-Print Network (OSTI)

502-6808 · Campus Recycling Service 476-2021 · sustainability.ucsf.edu/stay_informed/recycling_resources Binders Plastic Bags & Wrap Pretzel & Chip Bags Rubber bands Styrofoam Tyvek RECYCLE Aluminum foil & cans Reuse Recycle Compost receptacles can be found at campus cafes; Individual office composting is starting

Yamamoto, Keith

284

Neutron Halo Isomers in Stable Nuclei and their Possible Application for the Production of Low Energy, Pulsed, Polarized Neutron Beams of High Intensity and High Brilliance  

E-Print Network (OSTI)

We propose to search for neutron halo isomers populated via $\\gamma$-capture in stable nuclei with mass numbers of about A=140-180 or A=40-60, where the $4s_{1/2}$ or $3s_{1/2}$ neutron shell model state reaches zero binding energy. These halo nuclei can be produced for the first time with new $\\gamma$-beams of high intensity and small band width ($\\le$ 0.1%) achievable via Compton back-scattering off brilliant electron beams thus offering a promising perspective to selectively populate these isomers with small separation energies of 1 eV to a few keV. Similar to single-neutron halo states for very light, extremely neutron-rich, radioactive nuclei \\cite{hansen95,tanihata96,aumann00}, the low neutron separation energy and short-range nuclear force allows the neutron to tunnel far out into free space much beyond the nuclear core radius. This results in prolonged half lives of the isomers for the $\\gamma$-decay back to the ground state in the 100 ps-$\\mu$s range. Similar to the treatment of photodisintegration of the deuteron, the neutron release from the neutron halo isomer via a second, low-energy, intense photon beam has a known much larger cross section with a typical energy threshold behavior. In the second step, the neutrons can be released as a low-energy, pulsed, polarized neutron beam of high intensity and high brilliance, possibly being much superior to presently existing beams from reactors or spallation neutron sources.

D. Habs; M. Gross; P. G. Thirolf; P. Böni

2010-09-30T23:59:59.000Z

285

Evidence for Distinct Components of the Galactic Stellar Halo from 838 RR Lyrae Stars Discovered in the LONEOS-I Survey  

SciTech Connect

We present 838 ab-type RR Lyrae stars from the Lowell Observatory Near Earth Objects Survey Phase I (LONEOS-I). These objects cover 1430 deg{sup 2} and span distances ranging from 3-30kpc from the Galactic Center. Object selection is based on phased, photometric data with 28-50 epochs. We use this large sample to explore the bulk properties of the stellar halo, including the spatial distribution. The period-amplitude distribution of this sample shows that the majority of these RR Lyrae stars resemble Oosterhoff type I, but there is a significant fraction (26%) which have longer periods and appear to be Oosterhoff type II. We find that the radial distributions of these two populations have significantly different profiles ({rho}{sub OoI} {approx} R{sup -2.26{+-}0.07} and {rho}{sub OoII} {approx} R{sup -2.88{+-}0.11}). This suggests that the stellar halo was formed by at least two distinct accretion processes and supports dual-halo models.

Miceli, A; Rest, A; Stubbs, C W; Hawley, S L; Cook, K H; Magnier, E A; Krisciunas, K; Bowell, E; Koehn, B

2007-02-23T23:59:59.000Z

286

PAndAS IN THE MIST: THE STELLAR AND GASEOUS MASS WITHIN THE HALOS OF M31 AND M33  

SciTech Connect

Large-scale surveys of the prominent members of the Local Group have provided compelling evidence for the hierarchical formation of massive galaxies, revealing a wealth of substructure that is thought to be the debris from ancient and ongoing accretion events. In this paper, we compare two extant surveys of the M31-M33 subgroup of galaxies: the Pan-Andromeda Archaeological Survey of the stellar structure, and a combination of observations of the H I gaseous content, detected at 21 cm. Our key finding is a marked lack of spatial correlation between these two components on all scales, with only a few potential overlaps between stars and gas. The paucity of spatial correlation significantly restricts the analysis of kinematic correlations, although there does appear to be H I kinematically associated with the Giant Stellar Stream where it passes the disk of M31. These results demonstrate that different processes must significantly influence the dynamical evolution of the stellar and H I components of substructures, such as ram pressure driving gas away from a purely gravitational path. Detailed modeling of the offset between the stellar and gaseous substructures will provide a determination of the properties of the gaseous halos of M31 and M33.

Lewis, Geraint F. [Sydney Institute for Astronomy, School of Physics A28, The University of Sydney, NSW 2006 (Australia)] [Sydney Institute for Astronomy, School of Physics A28, The University of Sydney, NSW 2006 (Australia); Braun, Robert [CSIRO Astronomy and Space Science, P.O. Box 76, Epping, NSW 1710 (Australia)] [CSIRO Astronomy and Space Science, P.O. Box 76, Epping, NSW 1710 (Australia); McConnachie, Alan W. [Dominion Astrophysical Observatory, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada)] [Dominion Astrophysical Observatory, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Irwin, Michael J.; Chapman, Scott C. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom)] [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Ibata, Rodrigo A.; Martin, Nicolas F. [Observatoire de Strasbourg, 11, rue de l'Universite, F-67000 Strasbourg (France)] [Observatoire de Strasbourg, 11, rue de l'Universite, F-67000 Strasbourg (France); Ferguson, Annette M. N. [Institute for Astronomy, University of Edinburgh, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom)] [Institute for Astronomy, University of Edinburgh, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); Fardal, Mark [Department of Astronomy, University of Massachusetts, Amherst, MA 01003-9305 (United States)] [Department of Astronomy, University of Massachusetts, Amherst, MA 01003-9305 (United States); Dubinski, John [Department of Astronomy and Astrophysics, 50 St. George Street, University of Toronto, ON M5S 3H4 (Canada)] [Department of Astronomy and Astrophysics, 50 St. George Street, University of Toronto, ON M5S 3H4 (Canada); Widrow, Larry [Department of Physics, Queen's University, 99 University Avenue, Kingston, ON K7L 3N6 (Canada)] [Department of Physics, Queen's University, 99 University Avenue, Kingston, ON K7L 3N6 (Canada); Mackey, A. Dougal [Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Cotter Road, Weston Creek, ACT 2611 (Australia)] [Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Cotter Road, Weston Creek, ACT 2611 (Australia); Babul, Arif [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8W 3P6 (Canada)] [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8W 3P6 (Canada); Tanvir, Nial R. [Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH (United Kingdom)] [Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH (United Kingdom); Rich, Michael, E-mail: geraint.lewis@sydney.edu.au [Division of Astronomy, University of California, 8979 Math Sciences, Los Angeles, CA 90095-1562 (United States)] [Division of Astronomy, University of California, 8979 Math Sciences, Los Angeles, CA 90095-1562 (United States)

2013-01-20T23:59:59.000Z

287

Nuclear Charge Radii of Be-7,9,10 and the one-neutron halo nucleus Be-11  

E-Print Network (OSTI)

Nuclear charge radii of $^{7,9,10,11}$Be have been determined by high-precision laser spectroscopy. On-line measurements were performed with collinear laser spectroscopy in the $2s_{1/2} \\to 2p_{1/2}$ transition on a beam of Be$^{+}$ ions. Collinear and anticollinear laser beams were used simultaneously and the absolute frequency determination using a frequency comb yielded an accuracy in the isotope-shift measurements of about 1 MHz. Combination with accurate calculations of the mass-dependent isotope shifts yield nuclear charge radii. The charge radius decreases from $^7$Be to $^{10}$Be and then increases for the halo nucleus $^{11}$Be. When comparing our results with predictions of {\\it ab initio} nuclear structure calculations we find good agreement. Additionally, the nuclear magnetic moment of $^7$Be was determined to be $-1.3995(5)\\mu_{\\rm N}$ and that of $^{11}$Be from a previous $\\beta$-NMR measurement was confirmed.

W. Nörtershäuser; D. Tiedemann; M. Žáková; Z. Andjelkovic; K. Blaum; M. L. Bissell; R. Cazan; G. W. F. Drake; Ch. Geppert; M. Kowalska; J. Krämer; A. Krieger; R. Neugart; R. Sánchez; F. Schmidt-Kaler; Z. -C. Yan; D. T. Yordanov; C. Zimmermann

2008-09-15T23:59:59.000Z

288

Motion of halo compact objects in the gravitational potential of a low-mass model of the Galaxy  

E-Print Network (OSTI)

Recently, we derived a lower bound for the Galaxy mass in the approximation of a point mass potential, assuming a spherical symmetric ensemble of test bodies representing compact objects of the halo. This result was obtained for a representative of most general phase-space distribution functions consistent with the measured radial velocity dispersion, assuming no constraints on the form of the velocity dispersion anisotropy parameter. In this paper we make use of the representative phase function to set the initial conditions for a simulation of test bodies in a more realistic gravitational potential with the same total mass. The predicted radial velocity dispersion profile evolves to forms still consistent with the measured profile, proving structural stability of the point mass approximation and the reliability of its lower bound estimate for Galaxy mass of about $2.1\\times10^{11}\\mathrm{M}_{\\odot}$ within $150\\,\\mathrm{kpc}$. We derive also a relationship holding in spherical symmetry between the radial ve...

Sikora, Szymon; Ja?ocha, Joanna; Kutschera, Marek

2014-01-01T23:59:59.000Z

289

CONSTRAINTS ON THE SHAPE OF THE MILKY WAY DARK MATTER HALO FROM JEANS EQUATIONS APPLIED TO SLOAN DIGITAL SKY SURVEY DATA  

SciTech Connect

We search for evidence of dark matter in the Milky Way by utilizing the stellar number density distribution and kinematics measured by the Sloan Digital Sky Survey (SDSS) to heliocentric distances exceeding {approx}10 kpc. We employ the cylindrically symmetric form of Jeans equations and focus on the morphology of the resulting acceleration maps, rather than the normalization of the total mass as done in previous, mostly local, studies. Jeans equations are first applied to a mock catalog based on a cosmologically derived N-body+SPH simulation, and the known acceleration (gradient of gravitational potential) is successfully recovered. The same simulation is also used to quantify the impact of dark matter on the total acceleration. We use Galfast, a code designed to quantitatively reproduce SDSS measurements and selection effects, to generate a synthetic stellar catalog. We apply Jeans equations to this catalog and produce two-dimensional maps of stellar acceleration. These maps reveal that in a Newtonian framework, the implied gravitational potential cannot be explained by visible matter alone. The acceleration experienced by stars at galactocentric distances of {approx}20 kpc is three times larger than what can be explained by purely visible matter. The application of an analytic method for estimating the dark matter halo axis ratio to SDSS data implies an oblate halo with q{sub DM} = 0.47 {+-} 0.14 within the same distance range. These techniques can be used to map the dark matter halo to much larger distances from the Galactic center using upcoming deep optical surveys, such as LSST.

Loebman, Sarah R.; Ivezic, Zeljko; Quinn, Thomas R.; Governato, Fabio [Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195-1580 (United States); Brooks, Alyson M. [Department of Astronomy, University of Wisconsin, 475 North Charter Street, Madison, WI 53706 (United States); Christensen, Charlotte R. [Astronomy Department, University of Arizona, Tucson, AZ (United States); Juric, Mario, E-mail: sloebman@astro.washington.edu [LSST Corporation, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)

2012-10-10T23:59:59.000Z

290

Chemical Abundances and Dust in the Halo Planetary Nebula K648 in M15: Its Origin and Evolution based on an Analysis of Multiwavelength Data  

E-Print Network (OSTI)

We report an investigation of the extremely metal-poor and C-rich planetary nebula (PN) K648 in the globular cluster M15 using the UV to far-IR data obtained using the Subaru, HST, FUSE, Spitzer, and Herschel. We determined the nebular abundances of ten elements. The enhancement of F ([F/H]=+0.96) is comparable to that of the halo PN BoBn1. The central stellar abundances of seven elements are determined. The stellar C/O ratio is similar to the nebular C/O ratios from recombination line and from collisionally excited line (CEL) within error, and the stellar Ne/O ratio is also close to the nebular CEL Ne/O ratio. We found evidence of carbonaceous dust grains and molecules including Class B 6-9 um and 11.3 um polycyclic aromatic hydrocarbons and the broad 11 um feature. The profiles of these bands are similar to those of the C-rich halo PNe H4-1 and BoBn1. Based on the theoretical model, we determined the physical conditions of the gas and dust and their masses, i.e., 0.048 Msun and 4.95x10^{-7} Msun, respective...

Otsuka, Masaaki; Tajitsu, Akito

2015-01-01T23:59:59.000Z

291

7, 42854403, 2007 Halogens and polar  

E-Print Network (OSTI)

, Cambridge CB3 0ET, UK 5 McGill University, Canada 6 Environment Canada, Toronto, Canada 7 Institute-friendly Version Interactive Discussion EGU 11 School of Chemistry, University of Leeds, Leeds, LS29JT, UK 12

Paris-Sud XI, Université de

292

4, 53675380, 2004 Halogens and Free  

E-Print Network (OSTI)

and the formation of the stratospheric ozone hole (John- ston and Podolske, 1978; Cicerone et al., 1983; Farman et

Boyer, Edmond

293

Gas Chromatographic Analysis of Halogenated Quinoline Compounds  

Science Journals Connector (OSTI)

......hexamethyldisilazane at the beginning of each day. A column of QF-1 was prepared using a silated support (Chromosorb W-DMSC) to observe the activity of the support. The resolution was poor and undefined for all the chloroquinolines indicating the......

Paul C. Goodley; Marshall Gordon

1972-08-01T23:59:59.000Z

294

Gas Chromatographic Analysis of Halogenated Quinoline Compounds  

Science Journals Connector (OSTI)

......in the procedure section. Standard Mixtures The mixtures were...factors were calculated from five standard mixtures. These were calculated...QF-1 at 155 C (Analysis) Standard) Average Mole % Mole % (Average...silated support (Chromosorb W-DMSC) to observe the activity of......

Paul C. Goodley; Marshall Gordon

1972-08-01T23:59:59.000Z

295

Role for Brm in Cell Growth Control  

Science Journals Connector (OSTI)

...formation in Brm-deficient mice has led some authors to hypothesize that only...equipped with an automatic shutter and green fluorescent protein (GFP) filter sets, a 40 objective...illumination was supplied by a halogen bulb (100 W). Images were captured with...

Marjorie Coisy-Quivy; Olivier Disson; Virginie Roure; Christian Muchardt; Jean-Marie Blanchard; and Jean-Christophe Dantonel

2006-05-15T23:59:59.000Z

296

Visual pigment in the lens eyes of the box jellyfish Chiropsella bronzie  

Science Journals Connector (OSTI)

...and illuminated by standard fluorescent tubes. They were flown to...rich Blacklight (Phillips) fluorescent tubes. The medusae were fed...a 12 V 50 W quartz halogen bulb at the blaze angle of the microspectrophotometer...Environmental factors which may have led to the appearance of colour...

2010-01-01T23:59:59.000Z

297

Arrays and Cascades of Fluorescent Liquid-Liquid Waveguides: Broadband Light Sources for  

E-Print Network (OSTI)

Arrays and Cascades of Fluorescent Liquid-Liquid Waveguides: Broadband Light Sources) microchannel waveguides with liquid cores containing fluorescent dyes, excited by incident light from an external halogen bulb. Simultaneous use of multiple fluorophores in a common solution, in a single L2 light

Prentiss, Mara

298

HALO GAS AND GALAXY DISK KINEMATICS DERIVED FROM OBSERVATIONS AND LAMBDACDM SIMULATIONS OF Mg II ABSORPTION-SELECTED GALAXIES AT INTERMEDIATE REDSHIFT  

SciTech Connect

We obtained ESI/Keck rotation curves of 10 Mg II absorption-selected galaxies (0.3 <= z <= 1.0) for which we have WFPC-2/HST images and high-resolution HIRES/Keck and UVES/VLT quasar spectra of the Mg II absorption profiles. We perform a kinematic comparison of these galaxies and their associated halo Mg II absorption. For all 10 galaxies, the majority of the absorption velocities lie in the range of the observed galaxy rotation velocities. In 7/10 cases, the absorption velocities reside fully to one side of the galaxy systemic velocity and usually align with one arm of the rotation curve. In all cases, a constant rotating thick-disk model poorly reproduces the full spread of observed Mg II absorption velocities when reasonably realistic parameters are employed. In 2/10 cases, the galaxy kinematics, star formation surface densities, and absorption kinematics have a resemblance to those of high-redshift galaxies showing strong outflows. We find that Mg II absorption velocity spread and optical depth distribution may be dependent on galaxy inclination. To further aid in the spatial-kinematic relationships of the data, we apply quasar absorption-line techniques to a galaxy (v{sub c} = 180 km s{sup -1}) embedded in LAMBDACDM simulations. In the simulations, Mg II absorption selects metal-enriched 'halo' gas out to {approx}100 kpc from the galaxy, tidal streams, filaments, and small satellite galaxies. Within the limitations inherent in the simulations, the majority of the simulated Mg II absorption arises in the filaments and tidal streams and is infalling toward the galaxy with velocities between -200 km s{sup -1} <= v{sub r} <= -180 km s{sup -1}. The Mg II absorption velocity offset distribution (relative to the simulated galaxy) spans {approx}200 km s{sup -1} with the lowest frequency of detecting Mg II at the galaxy systematic velocity.

Kacprzak, Glenn G.; Murphy, Michael T. [Swinburne University of Technology, Victoria 3122 (Australia); Churchill, Christopher W.; Ceverino, Daniel; Klypin, Anatoly [New Mexico State University, Las Cruces, NM 88003 (United States); Steidel, Charles C., E-mail: gkacprzak@astro.swin.edu.a, E-mail: mmurphy@astro.swin.edu.a, E-mail: cwc@nmsu.ed, E-mail: ceverino@nmsu.ed, E-mail: aklypin@nmsu.ed, E-mail: ceverino@phys.huji.ac.i, E-mail: ccs@astro.caltech.ed [California Institute of Technology, Pasadena, CA 91125 (United States)

2010-03-10T23:59:59.000Z

299

Fermi 130 GeV gamma-ray excess and dark matter annihilation in sub-haloes and in the Galactic centre  

SciTech Connect

We analyze publicly available Fermi-LAT high-energy gamma-ray data and confirm the existence of clear spectral feature peaked at E{sub ?} = 130 GeV. Scanning over the Galaxy we identify several disconnected regions where the observed excess originates from. Our best optimized fit is obtained for the central region of Galaxy with a clear peak at 130 GeV with local statistical significance 4.5?. The observed excess is not correlated with Fermi bubbles. We compute the photon spectra induced by dark matter annihilations into two and four standard model particles, the latter via two light intermediate states, and fit the spectra with data. Since our fits indicate sharper and higher signal peak than in the previous works, data favors dark matter direct two-body annihilation channels into photons or other channels giving only line-like spectra. If Einasto halo profile correctly predicts the central cusp of Galaxy, dark matter annihilation cross-section to two photons is of order ten percent of the standard thermal freeze-out cross-section. The large dark matter two-body annihilation cross-section to photons may signal a new resonance that should be searched for at the CERN LHC experiments.

Tempel, Elmo; Hektor, Andi; Raidal, Martti, E-mail: elmo@aai.ee, E-mail: andi.hektor@cern.ch, E-mail: martti.raidal@cern.ch [NICPB, Ravala 10, Tallinn 10143 (Estonia)

2012-09-01T23:59:59.000Z

300

PROBING THE HALO FROM THE SOLAR VICINITY TO THE OUTER GALAXY: CONNECTING STARS IN LOCAL VELOCITY STRUCTURES TO LARGE-SCALE CLOUDS  

SciTech Connect

This paper presents the first potential connections made between two local features in velocity space found in a survey of M giant stars and stellar spatial inhomogeneities on global scales. Comparison to cosmological, chemodynamical stellar halo models confirms that the M giant population is particularly sensitive to rare, recent and massive accretion events. These events can give rise to locally observed velocity sequences-each made from a small fraction of debris from a massive progenitor, passing at high velocity through the survey volume, near the pericenter of the eccentric orbit of the system. The majority of the debris is found in much larger structures, whose morphologies are more cloud-like than stream-like and which lie at the orbital apocenters. Adopting this interpretation, the full-space motions represented by the observed M giant velocity features are derived under the assumption that the members within each sequence share a common space velocity. Orbit integrations are then used to trace the past and future trajectories of these stars across the sky revealing plausible associations with large, previously discovered, cloud-like structures. The connections made between nearby velocity structures and these distant clouds represent preliminary steps toward developing coherent maps of such giant debris systems. These maps promise to provide new insights into the origin of debris clouds, new probes of Galactic history and structure, and new constraints on the high-velocity tails of the local dark matter distribution that are essential for interpreting direct dark matter particle detection experiments.

Johnston, Kathryn V.; Sheffield, Allyson A. [Department of Astronomy, Columbia University, New York, NY 10027 (United States); Majewski, Steven R. [Department of Astronomy, University of Virginia, Charlottesville, VA 22904-0818 (United States); Sharma, Sanjib [Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006 (Australia); Rocha-Pinto, Helio J., E-mail: kvj@astro.columbia.edu [Observatorio do Valongo, Universidade Federal do Rio de Janeiro (Brazil)

2012-11-20T23:59:59.000Z

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

HELSINKI UNIVERSITY OF TECHNOLOGY ENE-47.153 Halogens, dioxins/Halogens, dioxins/furansfurans  

E-Print Network (OSTI)

OrimulsionTM ~700 Petroleum coke, "petcoke" ~ 300 Natural gas - * Iodine 0.5 - 1.5 mg/kg #12;HELSINKI

Zevenhoven, Ron

302

L Prize™: The Race for Super Efficient Light Bulbs  

Energy.gov (U.S. Department of Energy (DOE))

This September 23, 2008 webcast provided an overview of the Bright Tomorrow Lighting Prize (L Prize) technology competition. The L Prize calls for super-efficient SSL products to replace two of the...

303

A living light bulb, ultrasensitive biodetection made easy  

Science Journals Connector (OSTI)

A team of scientists led by Professor DW Pang at Wuhan University have developed a new class of fluorescence probes based on bacterial cells. These microbial factories manufacture semiconductor nanocrystals in...

Jing Shang; Xiaohu Gao

2014-06-01T23:59:59.000Z

304

Type of Space Bulb Type #/House Fixture Style Greenhouse #  

E-Print Network (OSTI)

841 360 8 F 32 T8/TL 841 360 9 F 32 T8/TL 841 360 MTPS 216 Ch. 1 F 72 T12 CW/VHO 72 1 Incandescent 60w 72 2 F 72 T12 CW/VHO 72 2 Incandescent 60w 72 5 F 72 T12 CW/VHO 72 5 Incandescent 60w 72 10 F 72 T12 CW/VHO 72 10 Incandescent 60w 72 #12;DR 1009 Ch. 27 F 032/431 4 Seed Chamber Ch. 28 F40T12/ADV 41 6

Pawlowski, Wojtek

305

Electrical and Optical Enhancement in Internally Nanopatterned Organic Light-Emitting Diodes  

E-Print Network (OSTI)

incandescent bulbs and fluorescent bulbs). Solid-stateindex (CRI) than fluorescent bulbs. Common examples where

Fina, Michael Dane

2012-01-01T23:59:59.000Z

306

Halo and Galaxy Formation Histories from the Millennium Simulation: Public release of a VO-oriented and SQL-queryable database for studying the evolution of galaxies in the LambdaCDM cosmogony  

E-Print Network (OSTI)

The Millennium Run is the largest simulation of the formation of structure within the $\\Lambda$CDM cosmogony so far carried out. It uses $10^{10}$ particles to follow the dark matter distribution in a cubic region 500$h^{-1}$Mpc on a side, and has a spatial resolution of 5 $h^{-1}$kpc. Application of simplified modelling techniques to the stored output of this calculation allows the formation and evolution of the $\\sim 10^7$ galaxies more luminous than the Small Magellanic Cloud to be simulated for a variety of assumptions about the detailed physics involved. As part of the activities of the German Astrophysical Virtual Observatory we have used a relational database to store the detailed assembly histories both of all the haloes and subhaloes resolved by the simulation, and of all the galaxies that form within these structures for two independent models of the galaxy formation physics. We have created web applications that allow users to query these databases remotely using the standard Structured Query Language (SQL). This allows easy access to all properties of the galaxies and halos, as well as to the spatial and temporal relations between them and their environment. Information is output in table format compatible with standard Virtual Observatory tools and protocols. With this announcement we are making these structures fully accessible to all users. Interested scientists can learn SQL, gain familiarity with the database design and test queries on a small, openly accessible version of the Millennium Run (with volume 1/512 that of the full simulation). They can then request accounts to run similar queries on the databases for the full simulations.

G. Lemson; the Virgo Consortium

2006-08-03T23:59:59.000Z

307

Theoretical studies of the dynamics of chemical reactions  

SciTech Connect

Recent research effort has focussed on several reactions pertinent to combustion. The formation of the formyl radical from atomic hydrogen and carbon monoxide, recombination of alkyl radicals and halo-alkyl radicals with halogen atoms, and the thermal dissociation of hydrogen cyanide and acetylene have been studied by modeling. In addition, the inelastic collisions of NCO with helium have been investigated.

Wagner, A.F. [Argonne National Laboratory, IL (United States)

1993-12-01T23:59:59.000Z

308

Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy  

DOE Patents (OSTI)

A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na.sub.4 B.sub.12 I.sub.11 SSB.sub.12 I.sub.11, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy.

Miura, Michiko (Hampton Bays, NY); Slatkin, Daniel N. (Southold, NY)

1997-03-18T23:59:59.000Z

309

Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy  

DOE Patents (OSTI)

A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na{sub 4}B{sub 12}I{sub 11}SSB{sub 12}I{sub 11}, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy. 1 fig.

Miura, M.; Slatkin, D.N.

1997-03-18T23:59:59.000Z

310

Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy  

DOE Patents (OSTI)

A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na.sub.4 B.sub.12 I.sub.11 SSB.sub.12 I.sub.11, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy.

Miura, Michiko (Hampton Bays, NY); Slatkin, Daniel N. (Southold, NY)

1995-10-03T23:59:59.000Z

311

Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy  

DOE Patents (OSTI)

A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na{sub 4}B{sub 12}I{sub 11}SSB{sub 12}I{sub 11}, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy. 1 fig.

Miura, M.; Slatkin, D.N.

1997-08-05T23:59:59.000Z

312

Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy  

DOE Patents (OSTI)

A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized. by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na.sub.4 B.sub.12 I.sub.11 SSB.sub.12 I.sub.11, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy.

Miura, Michiko (Hampton Bays, NY); Slatkin, Daniel N. (Southold, NY)

1997-08-05T23:59:59.000Z

313

Synthesis and Characterization of Halogen-Free Antiflammable Polyphosphonates Containing  

E-Print Network (OSTI)

flammability. Polyethylene and polypropylene, for example, possess heat of combustion properties on par exhibited low combustion heat release rate and total heat of combustion, which we believe arises from

314

Halogen bonds in some dihalogenated phenols: applications to crystal engineering  

Science Journals Connector (OSTI)

The preference of Br to form type II contacts over type I is explored by various techniques. The mechanical properties of some dihalogenated phenols are correlated with their structures.

Mukherjee, A.

2013-10-18T23:59:59.000Z

315

Atmospheric Lifetimes of Long-Lived Halogenated Species  

Science Journals Connector (OSTI)

...i) passage through high-temperature combustors, (ii) lightning...separately in what follows. High-temperature combustors. A fraction of all of...is processed through high-tem-perature combustors such as power plants...

A. R. Ravishankara; S. Solomon; A. A. Turnipseed; R. F. Warren

1993-01-08T23:59:59.000Z

316

Transient x-ray absorption spectroscopy of hydrated halogen atom  

E-Print Network (OSTI)

Time-resolved x-ray absorption spectroscopy has been used to observe the transient species generated by one-photon detachment of an electron from aqueous bromide. The K-edge spectrum of the short-lived Br(0) atom exhibits a resonant 1s-4p transition...

Elles, Christopher G.; Shkrob, Ilya A.; Crowell, Robert A.; Arms, Dohn A.; Landahl, Eric C.

2008-02-11T23:59:59.000Z

317

Halo and Galaxy Formation Histories from the Millennium Simulation: Public release of a VO-oriented and SQL-queryable database for studying the evolution of galaxies in the LambdaCDM cosmogony  

E-Print Network (OSTI)

The Millennium Run is the largest simulation of the formation of structure within the $\\Lambda$CDM cosmogony so far carried out. It uses $10^{10}$ particles to follow the dark matter distribution in a cubic region 500$h^{-1}$Mpc on a side, and has a spatial resolution of 5 $h^{-1}$kpc. Application of simplified modelling techniques to the stored output of this calculation allows the formation and evolution of the $\\sim 10^7$ galaxies more luminous than the Small Magellanic Cloud to be simulated for a variety of assumptions about the detailed physics involved. As part of the activities of the German Astrophysical Virtual Observatory we have used a relational database to store the detailed assembly histories both of all the haloes and subhaloes resolved by the simulation, and of all the galaxies that form within these structures for two independent models of the galaxy formation physics. We have created web applications that allow users to query these databases remotely using the standard Structured Query Langu...

Lemson, G

2006-01-01T23:59:59.000Z

318

Circular velocity profiles of dark matter haloes  

Science Journals Connector (OSTI)

......thank Avishai Dekel and Lucio Mayer for fruitful discussions and Nick Seymour for correcting the manuscript. This work was supported...Governato F., Verde L., Gardner J., Quinn T., Stadel J., Merritt D., Lake G., 2005, MNRAS, 357, 82. Springel V. , Yoshida......

Felix Stoehr

2006-01-01T23:59:59.000Z

319

Neutron halos in the Na isotopes  

Science Journals Connector (OSTI)

The neutron and proton density distributions of the Na isotopes out to the proton and neutron drip lines are calculated in the spherical Hartree-Fock model with a wide variety of density-dependent Skyrme interactions. The results are compared to recent experimental data for the interaction cross sections and for the rms radii. We discuss the role of the deformed intruder states and the problems associated with predicting the location of the neutron drip line for this mass region. © 1996 The American Physical Society.

B. A. Brown and W. A. Richter

1996-08-01T23:59:59.000Z

320

Experimental searches for galactic halo axions  

Science Journals Connector (OSTI)

...couplings to matter and radiation. It thus represents an...in the near future. In Japan, a group has been developing...couplings to matter and radiation. It thus represents an...in the near future. In Japan, a group has been developing...

2003-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Simulating a white dwarf dominated Galactic halo  

Science Journals Connector (OSTI)

......expected number of low-mass red dwarfs would violate the deep...debate (see, for example, Gyuk Gates 1999; Reid et al. 2001...ApJ, 503, 798. Gyuk G. , Gates E., 1999, MNRAS, 304, 281...Girardi L., Chiosi C., Wood P. R., 2001, AA, 371......

Chris B. Brook; Daisuke Kawata; Brad K. Gibson

2003-08-11T23:59:59.000Z

322

Secret Ninja Testing with HALO Software Engineering  

E-Print Network (OSTI)

· Testing can be tedious - there is low student engagement and interest in testing 2 #12;Gamification 3 · We propose a social approach to expose students to software testing using gamification · Our gamification gamification platform · Eclipse plugin · Maps various SE features to game world - Doesn't have to follow

Kaiser, Gail E.

323

Modeling galactic halos with predominantly quintessential matter  

E-Print Network (OSTI)

This paper discusses a new model for galactic dark matter by combining an anisotropic pressure field corresponding to normal matter and a quintessence dark energy field having a characteristic parameter $\\omega_q$ such that $-1Guzman et al. (2003). Less exceptional forms of quintessence dark energy do not yield the desired stable orbits and are therefore unsuitable for modeling dark matter.

F. Rahaman; Peter K. F. Kuhfittig; K. Chakraborty; M. Kalam; D. Hossain

2011-01-13T23:59:59.000Z

324

Bringing climate change down to earth : science and participation in Canadian and Australian climate change campaigns  

E-Print Network (OSTI)

bulbs with compact fluorescent bulbs. This led to a fair bitsuch as compact fluorescent bulbs, low-flow showerheads, andtechnologies: compact fluorescent light bulbs, energy saving

Padolsky, Miriam Elana

2006-01-01T23:59:59.000Z

325

E-Print Network 3.0 - alters olfactory bulb Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

... Source: Betz, William J. - Department of Physiology and Biophysics, University of Colorado Health Sciences Center Collection: Biology and Medicine 8 The Journal of...

326

Good genes and the maternal effects of polyandry on offspring reproductive success in the bulb mite  

Science Journals Connector (OSTI)

...four males with ionizing radiation, we eliminated any chance...of the four males with ionizing radiation, we eliminated any chance...a Co60 source. This dose prevents the eggs fertilized...by excluding the lower range of the distribution...

2004-01-01T23:59:59.000Z

327

Studying some mechanical properties of MgO with used neon bulb glass  

SciTech Connect

Ceramic compact of MgO +WT% of UNBG were sintered at different sintering temperature (700, 900, 1100, 1300)°c, under static air for 3 hours. X-ray diffraction and some mechanical properties were conducted. The maximum sintered density, compression; fracture strength and hardness were indicated for the compilation of MgO ?20 WT % UNBG, sintered at 1300 °c.

Issa, Tarik Talib [University of Baghdad, College of science physic department , Material Science group (Iraq); Khaleel, Saba Mahdi [Ministry of Industry and Minerals,Commission for Research And Industrial Development ,Chemical and Petrochemical Research Center, Baghdad (Iraq); Abdul Kareem, Noura Ammar [Ministry of Industry and Minerals, Commission for Research And Industrial Development ,Chemical and Petrochemical Research Center, Baghdad (Iraq)

2013-12-16T23:59:59.000Z

328

Stefan–Boltzmann law for the tungsten filament of a light bulb: Revisiting the experiment  

Science Journals Connector (OSTI)

A classical laboratory experiment to verify the Stefan-Boltzmann radiation law with the tungsten filaments of commercial incandescent lamps has been fully revisited collecting a fairly large amount of data with a computer-controlled four-channel power supply. In many cases the total power dissipated by the lamp is well described by a sum of two power-law terms with one exponent very close to 4 as predicted by the radiation law and the other very close to 1 as for simple heat conduction. This result was true even for filament surfaces with a shiny metallic appearance whose emissivity should vary with temperature.

2013-01-01T23:59:59.000Z

329

Development of Diagnostic Rules for a Dry Bulb Economizer Mixed Air Loop  

E-Print Network (OSTI)

Diagnostics of heating, ventilating, and air-conditioning (HVAC) systems is becoming increasingly important because of the rising cost of operation and maintenance of HVAC systems. At the same time, computer costs are tumbling allowing their use...

Underwood, D.

1990-01-01T23:59:59.000Z

330

Radio haloes from simulations and hadronic models – II. The scaling relations of radio haloes  

Science Journals Connector (OSTI)

......populate a region in the M HR 85 diagram with smaller values of R 85...of clusters in the P 1.4L X diagram is to admit that the observed...cluster mergers is followed by our MHD cosmological simulations that...of clusters in the P 1.4L X diagram, especially in the case of......

J. Donnert; K. Dolag; R. Cassano; G. Brunetti

2010-09-21T23:59:59.000Z

331

Spannungsdiagramm n nach Boussinesq  

Science Journals Connector (OSTI)

Spannungsdiagramm n nach Boussinesq, Druckzwiebel f, Boussinesqsches Spannungsdiagramm ? pressure bulb, bulb of pressure

2013-01-01T23:59:59.000Z

332

ANALYSIS OF THE CALIFORNIA ENERGY INDUSTRY  

E-Print Network (OSTI)

firms currently producing fluorescent bulbs. Phantom™ tubea per- centage of fluorescent light bulbs from the installed

Authors, Various

2010-01-01T23:59:59.000Z

333

Sleep, mood, and circadian responses to bright green light during sleep  

E-Print Network (OSTI)

white light from fluorescent bulbs, as point sources mightthan incandescent bulbs. Also, fluorescent light is easier

Grandner, Michael Andrew

2007-01-01T23:59:59.000Z

334

Protocol for Maximizing Energy Savings and Indoor Environmental Quality Improvements when Retrofitting Apartments  

E-Print Network (OSTI)

bulbs with compact fluorescent bulbs.  In addition, the a?light bulbs with  fluorescent light bulbs that use less light  bulbs  with  compact  fluorescent lights   Replace 

Noris, Federico

2014-01-01T23:59:59.000Z

335

Untitled  

U.S. Energy Information Administration (EIA) Indexed Site

0. Number of Lights by Bulb Type by Room, 1993 0. Number of Lights by Bulb Type by Room, 1993 Bulb Type Incandescent Fluorescent Other Room Total Low Medium High Unknown Short Long Compact Halogen Other/ unknown Total 4,196 431 2,811 409 14 159 173 34 24 141 Bathroom 621 44 417 81 4 35 14 2 1 23 Bedroom 1,121 119 868 66 6 8 5 9 8 32 Dining Room 218 28 119 51 2 0 1 1 2 14 Den/Family/ Rec Room 279 28 171 42 1 7 12 2 3 13 Hallway/Stairs 193 42 136 6 0 1 3 0 0 5 Kitchen 820 80 440 70 1 85 104 12 1 27 Living Room 711 65 511 80 0 11 8 8 8 20 Laundry Room/Other 233 25 149 13 0 12 26 0 1 7 Note: These data are from the 474 households included in the Lighting Supplement. The supplement was not designed to weight the data to the population level. Source: Energy Information Administration, Office of Energy Markets and End Use, Forms EIA-457A-C, E, and H of the 1993 Residential Energy Consumption Survey. Go to Table 4.21

336

Demonstration Assessment of Light Emitting Diode (LED) Residential Downlights and Undercabinet Lights in the Lane County Tour of Homes, Eugene, Oregon  

SciTech Connect

In August 2008 the Pacific Northwest National Laboratory (PNNL) conducted a light emitting diode (LED) residential lighting demonstration project for the U.S. Department of Energy (DOE), Office of Building Technologies, as part of DOE’s Solid State Lighting (SSL) Technology Demonstration Gateway Program. Two lighting technologies, an LED replacement for downlight lamps (bulbs) and an LED undercabinet lighting fixture, were tested in the demonstration which was conducted in two homes built for the 2008 Tour of Homes in Eugene, Oregon. The homes were built by the Lane County Home Builders Association (HBA), and Future B Homes. The Energy Trust of Oregon (ETO) also participated in the demonstration project. The LED downlight product, the LR6, made by Cree LED Lighting Solutions acts as a screw-in replacement for incandescent and halogen bulbs in recessed can downlights. The second product tested is Phillips/Color Kinetics’ eW® Profile Powercore undercabinet fixture designed to mount under kitchen cabinets to illuminate the countertop and backsplash surfaces. Quantitative and qualitative measurements of light performance and electrical power usage were taken at each site before and after initially installed halogen and incandescent lamps were replaced with the LED products. Energy savings and simple paybacks were also calculated and builders who toured the homes were surveyed for their responses to the LED products. The LED downlight product drew 12 Watts of power, cutting energy use by 82% compared to the 65W incandescent lamp and by 84% compared to the 75W halogen lamp. The LED undercabinet fixture drew 10 watts, cutting energy use by 83% to 90% compared to the halogen product, which was tested at two power settings: a low power 60W setting and a high power 105W setting. The LED downlight consistently provided more light than the halogen and incandescent lamps in horizontal measurements at counter height and floor level. It also outperformed in vertical illuminance measurements taken on the walls, indicating better lateral dispersion of the light. The undercabinet fixture’s light output was midway between the low and high power halogen undercabinet fixture light outputs (35.8 foot candle versus 13.4 fc and 53.4 fc) but it produced a more uniform light (max/min ratio of 7.0 versus 10.8). The color correlated temperature (CCT, the blue or yellowness) of the LED light correlated well with the halogen and incandescent lights (2675 K vs 2700 K). The color rendering of the LED downlight also correlated well at 92 CRI compared to 100 CRI for the halogen and incandescent lamps. The LED undercabinet fixture had measures of 2880 K CCT and 71 CRI compared to the 2700 K and 100 CRI scores for the halogen undercabinet fixture. Builders who toured the homes were surveyed; they gave the LED downlight high marks for brightness, said the undercabinet improved shadows and glare and said both products improved overall visibility, home appearance, and home value. Paybacks on the LED downlight ranged from 7.6 years (assuming electricity cost of 11 c/kWh) to 13.5 years (at 5C/kWh). Paybacks on the LED undercabinet fixture in a new home ranged from 4.4 years (11c/kWh electricity) to 7.6 years (5c/kWh) based on product costs of $95 per LED downlight and $140 per LED undercabinet fixture at 3 hrs per day of usage for the downlight and 2 hrs per day for the undercabinet lighting.

Ton, My K.; Richman, Eric E.; Gilbride, Theresa L.

2008-11-10T23:59:59.000Z

337

Halogen-elimination photochemistry and oxygen-activation chemistry of late transition-metal complexes  

E-Print Network (OSTI)

Multi-electron reaction chemistry, from both ground- and excited-state species, is at the heart of many topics in renewable energy and catalysis. In this thesis, two classes of reactions central to the themes of energy ...

Teets, Thomas S. (Thomas Sebastian)

2012-01-01T23:59:59.000Z

338

Analysis and Characterization of Halogenated Transformation Products of Pharmaceuticals and Personal Care Products in Wastewater Effluent  

E-Print Network (OSTI)

Immunosorbent assay for triclosan. Application to wastewaterR. ; Letcher, R. J. , Triclosan in waste and surface watersformation of chlorinated triclosan derivatives in wastewater

Bulloch, Daryl Neil

2013-01-01T23:59:59.000Z

339

The Halogenation of Oils with Special Attention to the Method of Wijs  

E-Print Network (OSTI)

by him in the following manner: !• In the preparation of the solutions. HgCl 8 + 41 = Hg I a + 2 IC1 IC1 + H 20 5 HC1 + HIO 2. On keeping the solution. 2 HIO + C 2H 60 = 21 + 2H 20 + C 2H 40 3. In the absorption (oleic acid). C0 2H.Ci 7H a a + HIO... at once a substance capable of liberating iodine from potassium iodide. He expressed the chemical change by the following equation: HgCl + I 2 - Hg C1I + IC1 Ephraim regarded the fact that he could ob­ tain results identical to those of Hubl, by using...

Rhodes, Edmund Oliver

1913-05-15T23:59:59.000Z

340

Halogenated Volatile Organic Compounds from the Use of Chlorine-Bleach-Containing Household Products  

Science Journals Connector (OSTI)

A number of household cleaning products (bleaches, mildew stain removers, toilet cleaners, cleaning sprays, gels, and scouring powders) contain sodium hypochlorite (NaOCl, ?5%). ... Each tube was packed at the upstream (sampling) end with 3 mm silanized glass-wool followed by a series of sections of 150 mg Tenax TA (60/80 mesh) (Supelco, Bellefonte, PA, USA), 3 mm silanized glass-wool, 100 mg Carboxen 1000 (Supelco, Bellefonte, PA), and finally, 3 mm silanized glass-wool at the downstream end. ...

Mustafa Odabasi

2008-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Gas Chromatography—Microwave-Induced Plasma for the Determination of Halogenated Hydrocarbons  

Science Journals Connector (OSTI)

......Spectroscopic Microwave generator: Applied Research...helium and argon at atmospheric pressures. Spec...plasma in helium at atmospheric pressure as an element-selective...organic compounds in water by gas chromatography (atmospheric pres sure helium......

M.M. Abdillahi

1990-12-01T23:59:59.000Z

342

Photoelectron spectroscopy of the halogen oxide anions FO-, CIO-, BrO-, IO-, OCIO-, and OIO-  

E-Print Network (OSTI)

of Colorado and National Institute of Standards and Technology, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0440 (Received 29 January 1992; accepted 28 February 1992, by Dotan et al." Vogt et a1.12measured the energy depend- ence of the ClO- product channel in the reaction

Lineberger, W. Carl

343

Low-Level Detections of Halogenated Volatile Organic Compounds in Groundwater  

E-Print Network (OSTI)

Assessments L. Niel Plummer1 ; Eurybiades Busenberg2 ; Sandra M. Eberts3 ; Laura M. Bexfield4 ; Craig J. Brown5 ; Lynne S. Fahlquist6 ; Brian G. Katz7 ; and Matthew K. Landon8 Abstract: Concentrations study areas in the United States. In each case, the untreated water sample was used for drinking

344

Evaporative evolution of Martian brines based on halogens in nakhlites and MER samples  

SciTech Connect

Comparison of Cl and Br from Nakhla viens to MER samples suggests two kinds of brine solutions existed on Mars, one early and one late in the evaporation sequence. These solutions precipitated the secondary salts at the Meridiani and Gusev sites. We have recently reported the Cl and Br abundances determined by APS X-ray Microprobe and EMPA analyses of secondary aqueous minerals in Nakhla veins and discussed the significance of Cl-Br correlations with respect to the evolution of brine solutions on Mars. In that study, we suggested that the low Br concentration ({approx}10 ppm) in Lafayette Iddingsite is indicative of early stage of evaporation during progressive evolution of Martian brine solutions, which is, in turn, consistent with the petrographic evidence of early deposition of salt sequence of carbonate-sulfate- and no halite in Lafayette. We showed that the high Br concentrations of {approx}240 ppm in secondary salts in Nakhla veins similarly indicate late stages of evaporation in evolving Martian brine solutions which is again consistent with petrographic evidence of late stage deposition of salt sequence i.e. carbonate-sulfate-halite in Nakhla. When sea water evaporates under equilibrium conditions, the most insoluble carbonates (siderite and calcite) deposit first, followed by sulfates (gypsum and anhydrite) and finally the water-soluble halides are precipitated when the water content is sufficiently low. In the present study, we make a detailed comparison of Cl/Br ratios in secondary minerals in nakhlites with those in MER soils and rocks at Gusev and Meridiani and show that the compositions of solutions that inundated Lafayette iddingsite (early stage) and Nakhla veins (late stage) include the range of solution-compositions that gave rise to a variety of secondary salts at Gusev and Meridiani sites. Further, the results obtained here suggest that two kinds of brine solutions (one, late and the other, early or intermediate stage) seem to have inundated most of the rocks and soils to varying degrees and precipitated the secondary salts at Meridiani and Gusev sites.

Rao, M.N.; Sutton, S.R.; McKay, D.S. (Lockheed); (UC); (NASA)

2005-02-04T23:59:59.000Z

345

Halogen-Based Plasma Etching of Novel Field-Effect Transistor Gate Materials  

E-Print Network (OSTI)

of Silicon Etching by a Cf4 Plasma. Journal of Vacuumplasma with the addition of CF4, Cl-2, and N-2. Japaneseet al. , The effect of CF4 addition on Ru etching with

Kiehlbaugh, Kasi Michelle

2009-01-01T23:59:59.000Z

346

Estimating the climate significance of halogen-driven ozone loss in the tropical marine troposphere  

E-Print Network (OSTI)

Marine and Atmospheric Science, University of Miami, Miami, FL, USA 6 Department of Chemistry, University of California, Irvine, CA, USA 7 Jet Propulsion

2012-01-01T23:59:59.000Z

347

Gas Chromatography—Microwave-Induced Plasma for the Determination of Halogenated Hydrocarbons  

Science Journals Connector (OSTI)

......microwave-induced plasma detector. The...generator (2450 MHz frequency) was...microwave-induced plasma in helium at atmospheric pressure as an...compounds with atmospheric pressure helium microwave induced plasma-atomic emission......

M.M. Abdillahi

1990-12-01T23:59:59.000Z

348

The Carcinogenic Activities of Certain Halogen Derivatives of 4-Dimethylaminoazobenzene in the Rat  

Science Journals Connector (OSTI)

...was rearranged (19) by heating it at 47 to 50 C. for...cerelose), 77; and corn oil, 5. After analysis of...dissolved in the corn oil of the diet with mild...drop of halibut liver oil per month. In the first...P. Rusch and J. M. Price for the histological examinations...

J. A. Miller; R. W. Sapp; and E. C. Miller

1949-11-01T23:59:59.000Z

349

COLLISIONS OF HALOGEN (2P) AND RARE GAS (1S) ATOMS  

E-Print Network (OSTI)

involving 2p excited states of alkali atoms, with groundstate rare gas atoms (RG), though other systems have been2p ) AND RARE GAS (IS) ATOMS Christopher Hank Becker (Ph. D.

Becker, Christopher Hank

2011-01-01T23:59:59.000Z

350

Solid-State Halogen Atom Source for Chemical Dynamics and Etching...  

NLE Websites -- All DOE Office Websites (Extended Search)

Br and Br* in controllable quantities and velocities, thus providing an attractive UHV compatible solid-state radical atom source. The solid-state atom source is in principle...

351

Selective Detection of Phosphorus, Sulfur, and Halogen Compounds in the Gas Chromatography of Drugs and Pesticides  

Science Journals Connector (OSTI)

......ethane since higher hydrocarbons would inter- fere...presence of many hydrocarbons by using xenon as...passes through a combustion tube heated to 800...passage through the combustion tube and are not...PLUG- - TRANSITE HEAT SHIELD -- TO FURNACE...presentation of data. Thus, the high......

H. P. Burchfield; D. E. Johnson; J. W. Rhoades; R. J. Wheeler

1965-01-01T23:59:59.000Z

352

Analysis and Characterization of Halogenated Transformation Products of Pharmaceuticals and Personal Care Products in Wastewater Effluent  

E-Print Network (OSTI)

from a Millipore water purification system (Billerica, MA).from a Millipore water purification system (Billerica, MA).

Bulloch, Daryl Neil

2013-01-01T23:59:59.000Z

353

Investigating the biosynthesis of halogenated meroterpenoid natural products from marine actinomycetes  

E-Print Network (OSTI)

0.25 M lithium sulfate 0.2 M calcium acetate 0.2 M calciumlithium nitrate none none none none none none 0.3 M ammonium acetate

Winter, Jaclyn Marie

2010-01-01T23:59:59.000Z

354

Investigating the Biosynthesis of Halogenated Meroterpenoid Natural Products from Marine Actinomycetes  

E-Print Network (OSTI)

0.25 M lithium sulfate 0.2 M calcium acetate 0.2 M calciumlithium nitrate none none none none none none 0.3 M ammonium acetate

Winter, Jaclyn Marie

2010-01-01T23:59:59.000Z

355

Crossover energetics for halogenated Si(100): Vacancy line defects, dimer vacancy lines, and atom vacancy lines  

Science Journals Connector (OSTI)

We investigated surface patterning of I-Si(100)-(2×1) both experimentally and theoretically. Using scanning tunneling microscopy, we first examined I destabilization of Si(100)-(2×1) at near saturation. Dimer vacancies formed on the terraces at 600 K, and they grew into lines that were perpendicular to the dimer rows, termed vacancy line defects. These patterns were distinctive from those induced by Cl and Br under similar conditions since the latter formed atom and dimer vacancy lines that were parallel to the dimer rows. Using first-principles density functional theory, we determined the steric repulsive interactions associated with iodine and showed how the observed defect patterns were related to these interactions. Concentration-dependent studies showed that the vacancy patterns were sensitive to the I concentration. Dimer and atom vacancy lines that were elongated along the dimer row direction were favored at lower coverage. Atom vacancy lines dominated at ?0.8ML, they coexisted with dimer vacancy lines at ?0.6-0.7ML, and dimer vacancy lines were exclusively observed below ?0.5ML. These surface patterns reflect the mean strength of the adatom repulsive interactions.

G. J. Xu; N. A. Zarkevich; Abhishek Agrawal; A. W. Signor; B. R. Trenhaile; D. D. Johnson; J. H. Weaver

2005-03-30T23:59:59.000Z

356

Halogenated Hydrocarbons in Dutch Water Samples Over the Years 1969 – 1977  

Science Journals Connector (OSTI)

The results of a surveillance program with respect to hexa-chlorobenzene, ?-, ?- and ?-hexachlorocyclohexane, heptachlor, heptachlorepoxide, dieldrin, endrin, o.p’-DDT, p.p’-DDT, p.p’-DDE, TDE, ?- and ?-endosu...

Ronald C. C. Wegman; Peter A. Greve

1980-01-01T23:59:59.000Z

357

Essays in Public Economics and Development  

E-Print Network (OSTI)

adopt compact fluorescent light bulbs (CFLs), and possibleof compact fluorescent light bulbs (CFLs) from PROCEL, andAdoption of compact fluorescent light bulbs In the PROCEL

Gerard, Francois

2013-01-01T23:59:59.000Z

358

Max Tech and Beyond: Maximizing Appliance and Equipment Efficiency by Design  

E-Print Network (OSTI)

for the motor (30 W). Fluorescent bulbs gain 75% efficiencyreplaced with compact fluorescent bulbs, with LEDs being aCommission compact fluorescent light bulb cubic feet per

Desroches, Louis-Benoit

2012-01-01T23:59:59.000Z

359

A world of cruelty in Titus Andronicus /  

E-Print Network (OSTI)

were the flickering fluorescent bulbs, a single scream andmade mostly for the fluorescent bulbs. Kristin Hayes, thecold light of a fluorescent bulb exposes and illuminates

Brody, Joshua Kahan

2013-01-01T23:59:59.000Z

360

DSM Electricity Savings Potential in the Buildings Sector in APP Countries  

E-Print Network (OSTI)

150 million compact fluorescent light bulbs in 2010. (ChinaCleaners Incandescent Bulbs Fluorescent Lamps Ballasts forincandescent bulbs with compact fluorescent lamps. Consumers

McNeil, MIchael

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Delivering Energy Efficiency to Middle Income Single Family Households  

E-Print Network (OSTI)

system CFL – Compact Fluorescent Light Bulb IAQ – Indoor Airdiscount compact fluorescent light bulbs (CFLs) or providediscount compact fluorescent light bulbs (CFLs) or provide

Zimring, Mark

2012-01-01T23:59:59.000Z

362

Zinc Oxide and Nitride Nanowire Based Light Emitting Diodes  

E-Print Network (OSTI)

of incandescent light bulb, fluorescent lamp, and blue lightof incandescent light bulb, fluorescent lamp, and blue lightincandescent bulb and is on the same order as fluorescent

Lai, Elaine Michelle

2009-01-01T23:59:59.000Z

363

Behavioral Perspectives on Home Energy Audits: The Role of Auditors, Labels, Reports, and Audit Tools on Homeowner Decision Making  

E-Print Network (OSTI)

and  dishwasher,  all  fluorescent  bulbs   Changed  about  on.   I  use  more  fluorescent  bulbs  now.   Increased  Furnace   Installed  fluorescent  light  bulbs   Insulate  

Ingle, Aaron

2013-01-01T23:59:59.000Z

364

PowerChoice Residential Customer Response to TOU Rates  

E-Print Network (OSTI)

or pin based compact fluorescent bulbs. If asked, count both15. How many compact fluorescent bulbs have you installedregular fixtures with fluorescent bulbs? Installing timers

Peters, Jane S.

2010-01-01T23:59:59.000Z

365

Estimate of Technical Potential for Minimum Efficiency Performance Standards in 13 Major World Economies  

E-Print Network (OSTI)

for typical wattage of incandescent bulbs and hours of usagefor which we assume that incandescent bulbs gradually getsimilar to that of incandescent or fluorescent bulbs. These

Letschert, Virginie

2013-01-01T23:59:59.000Z

366

Impact of Large Scale Energy Efficiency Programs On Consumer Tariffs and Utility Finances in India  

E-Print Network (OSTI)

consumers to replace incandescent bulbs with CFLs. Weprograms (for example, incandescent bulbs) and j indicatesend-use (for example, incandescent bulbs) in 2011 and, T c

Abhyankar, Nikit

2011-01-01T23:59:59.000Z

367

Energy Data Sourcebook for the U.S. Residential Sector  

E-Print Network (OSTI)

device. For instance, an incandescent bulb used one hour persockets. We create incandescent bulb UECs by both hours ofand lifetimes for standard incandescent bulbs and their more

Wenzel, T.P.

2010-01-01T23:59:59.000Z

368

Conditions of converting a hydroelectric station with horizontal bulb units to a hydroelectric station-pumped-storage station regime  

Science Journals Connector (OSTI)

1. On-site investigations of the equipment of the Kiev HES confirmed the possibility in principle of realizing t...

S. I. Potashnik; I. I. Ivanov; V. A. Osadchuk…

1989-06-01T23:59:59.000Z

369

Chemical Dependencies of Learning in the Rabbit Olfactory Bulb: Acquisition of the Transient Spatial Pattern Chance Depends on Norepinephrine  

E-Print Network (OSTI)

electrode were placed in the orhit..‘I'he orbital cavity and dorsal openings were tilled \\\\ ith sterile agar-

Gray, Charles M; Freeman, Walter J III; Skinner, James E

1986-01-01T23:59:59.000Z

370

E-Print Network 3.0 - astatine 212 Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

Collection: Biology and Medicine ; Engineering 36 Zevenhoven & Kilpinen Halogens, dioxinsfurans 17.6.2001 7-1 Chapter 7 Halogens, Summary: .1 Introduction The halogens are...

371

E-Print Network 3.0 - astatine chlorides Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

and Medicine ; Environmental Sciences and Ecology 27 Zevenhoven & Kilpinen Halogens, dioxinsfurans 17.6.2001 7-1 Chapter 7 Halogens, Summary: .1 Introduction The halogens are...

372

E-Print Network 3.0 - astatine compounds Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

University of Waterloo Collection: Chemistry 34 Zevenhoven & Kilpinen Halogens, dioxinsfurans 17.6.2001 7-1 Chapter 7 Halogens, Summary: .1 Introduction The halogens are...

373

E-Print Network 3.0 - astatine 215 Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

Physics Group Collection: Materials Science 35 Zevenhoven & Kilpinen Halogens, dioxinsfurans 17.6.2001 7-1 Chapter 7 Halogens, Summary: .1 Introduction The halogens are...

374

On the alleged duality of the Galactic halo  

Science Journals Connector (OSTI)

......proper motion part and by a lift via the velocity crossovers...distribution (green data points) for the four different subsamples and...highest significance. We point out that even this strong...having diminished. We point out that these values......

Ralph Schönrich; Martin Asplund; Luca Casagrande

2011-08-21T23:59:59.000Z

375

The first generation of star-forming haloes  

Science Journals Connector (OSTI)

......undergoing molecular hydrogen cooling although...or supernovae. methods: N-body simulations...threshold for atomic hydrogen-line cooling...cool by molecular hydrogen (H2) transitions...a catalyst via H production (when z 100...developed analytic methods to model early baryonic......

Darren S. Reed; Richard Bower; Carlos S. Frenk; Liang Gao; Adrian Jenkins; Tom Theuns; Simon D. M. White

2005-10-21T23:59:59.000Z

376

Radius of B-8 halo from the asymptotic normalization coefficient  

E-Print Network (OSTI)

W !& 5 ( lB ,mlB jBm jB ^JAM A jBm jBuJBM B& 3^JpM plBmlBu jbm jB&i lBY lBmlB~r? !IAplB jB B ~r !. ~1! A is the antisymmetrization operator, w is a bound-state IAplB jB B ~r !?CAplB jB B WhB ,lB11/2~2kBr ! r . ~3! Here CAplB jB B... overlap integrals I(r). The multipole expansion is carried out over lB , jB values allowed by angular momentum and parity conservation for the virtual process B?A1p . The overlap integral is not an eigenfunction of the total Hamiltonian, and hence...

Carstoiu, F.; Trache, L.; Gagliardi, Carl A.; Tribble, Robert E.; Mukhamedzhanov, AM.

2001-01-01T23:59:59.000Z

377

The present and future mass of the Milky Way halo  

Science Journals Connector (OSTI)

......beta from the uniform energy prior (n = 2) to a...noting that the uniform energy prior is biased towards...We regard this as an economical assumption to make...gravity field at the solar radius whilst the dwarf...for v 0 and the uniform energy (n = 2) prior was used......

M. I. Wilkinson; N. W. Evans

1999-12-11T23:59:59.000Z

378

Hi-tech halo to mark Central Park's birthday  

Science Journals Connector (OSTI)

... The pyrotechnic highlight of most birthdays is a ring of candles. But in honour of Monday' ... , based in Brookhaven, New York. The company has invented high-tech rockets dubbed 'pyrotechnic pixel bursts' that enable the artist to 'paint' in the sky, explains executive ...

Helen Pearson

2003-07-19T23:59:59.000Z

379

The halo mass function through the cosmic ages  

Science Journals Connector (OSTI)

......Cole 1994; Summers, Davis Evrard 1995; Audit, Teyssier Alimi 1998); deltaFOF 74...et al. MNRAS (2012) 426:2046. Audit E. , Teyssier R., Alimi J.-M. AA...Astropart. Phys. (2013) 1:019. LSST Dark Energy Science Collaboration. (2012) preprint......

William A. Watson; Ilian T. Iliev; Anson D?Aloisio; Alexander Knebe; Paul R. Shapiro; Gustavo Yepes

2013-01-01T23:59:59.000Z

380

Thin disc, thick disc and halo in a simulated galaxy  

Science Journals Connector (OSTI)

......code, and the simulation re-run: the stochastic nature of...hydrodynamics (SPH) code gasoline (Wadsley, Stadel Quinn 2004). gasoline employs cooling based on the...populations simply using a straight line with equation [O/Fe......

C. B. Brook; G. S. Stinson; B. K. Gibson; D. Kawata; E. L. House; M. S. Miranda; A. V. Macciò; K. Pilkington; R. Roskar; J. Wadsley; T. R. Quinn

2012-10-11T23:59:59.000Z

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Funding Sustainable Initiatives: Should Williams Implement a Revolving Loan Fund?  

E-Print Network (OSTI)

to replace its incandescent light bulbs with more efficient compact fluorescent (CFL) light bulbs. These light bulbs use 2/3 less energy than #12;Terra 4 standard incandescent bulbs, but they are more

Aalberts, Daniel P.

382

FINAL PROJECT REPORT LOAD MODELING TRANSMISSION RESEARCH  

E-Print Network (OSTI)

to be the compact fluorescent bulbs (CFBs) that the engineerbulbs with compact fluorescent bulbs (CFBs) continues to

Lesieutre, Bernard

2013-01-01T23:59:59.000Z

383

Catalog of DC Appliances and Power Systems  

E-Print Network (OSTI)

loss for the compact fluorescent bulb replacement. For mosta light bulb or tube, a compact fluorescent lamp typically

Garbesi, Karina

2012-01-01T23:59:59.000Z

384

Energy Consumption, Efficiency, Conservation, and Greenhouse Gas Mitigation in Japan's Building Sector  

E-Print Network (OSTI)

and a washroom with bulb-type fluorescent lamps, (5) closingusing incandescent bulbs to fluorescent lamps. This switch

2006-01-01T23:59:59.000Z

385

Effects of trace metals on diatom export products from the euphotic zone and significance for biogeochemical cycles  

E-Print Network (OSTI)

was provided by 3 cool white fluorescent bulbs and oneplant growth fluorescent bulb at ?4300 lux. All cultures

Richter, Daniel J.

386

Laboratory Ventilation SafetyLaboratory Ventilation Safety J. Scott WardJ. Scott Ward  

E-Print Network (OSTI)

the incandescent light bulb in 1879.incandescent light bulb in 1879. #12;First Labconco Hood 1936First Labconco

Farritor, Shane

387

Appliances and Commercial Equipment Standards  

NLE Websites -- All DOE Office Websites (Extended Search)

Torchieres Torchieres Sign up for e-mail updates on regulations for this and other products The Department of Energy (DOE) has regulated the energy efficiency level of torchieres since 2005. A torchiere, or torch lamp, is a lamp fixture with a tall (such as 5 foot) stand of wood or metal. Torchiere lamps use fluorescent or halogen incandescent light bulbs. Recent Updates | Standards | Test Procedures | Waiver, Exception, and Exemption Information | Statutory Authority | Historical Information | Contact Information Recent Updates There are no recent updates for this product. Standards for Torchieres The following content summarizes the energy conservation standards of DOE's regulations. The text is not an official reproduction of the Code of Federal Regulations and should not be used for legal research or citation.

388

This Month on Energy Savers: February 2011 | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

1 1 This Month on Energy Savers: February 2011 March 1, 2011 - 8:54am Addthis Allison Casey Senior Communicator, NREL It's still a bit early for spring, but we at Energy Savers have major spring fever. We're pretty sure the rest of the country does, too, after a winter where all 50 states had at least some snow on the ground (and some of you had-or still have-much, much more than others!). So we're thinking spring and bidding a fond farewell (good riddance?) to February and a hearty hello to March. Here's a look back at what happened this month: New or Noteworthy on Energy Savers Did you know that upgrading 15 of the inefficient incandescent light bulbs in your home could save you about $50 per year. New lighting standards take effect in 2012, and money-saving options such as halogen

389

Multicolor Photoinitiators for Radical and Cationic Polymerization: Monofunctional vs Polyfunctional Thiophene Derivatives  

Science Journals Connector (OSTI)

Their abilities to initiate, when combined with an iodonium salt (and optionally N-vinylcarbazole), a ring-opening cationic photopolymerization of epoxides and radical photopolymerization of acrylates under various different irradiation sources (i.e., very soft halogen lamp irradiation, laser diode at 405, 457, 473, 532, and 635 nm and blue LED bulb at 462 nm) have been investigated. ... They are also particularly efficient for the cationic and radical photopolymerization of an epoxide/acrylate blend in a one-step hybrid cure and lead to the formation of an interpenetrated polymer network IPN (30 s for getting tack-free coatings). ... The photochemical mechanisms are studied by steady state photolysis, fluorescence, cyclic voltammetry, electron spin resonance spin trapping, and laser flash photolysis techniques. ...

Pu Xiao; Frédéric Dumur; Damien Thirion; Sébastien Fagour; Antoine Vacher; Xavier Sallenave; Fabrice Morlet-Savary; Bernadette Graff; Jean Pierre Fouassier; Didier Gigmes; Jacques Lalevée

2013-08-20T23:59:59.000Z

390

Method of Dehalogenation using Diamonds  

SciTech Connect

A method for preparing olefins and halogenated olefins is provided comprising contacting halogenated compounds with diamonds for a sufficient time and at a sufficient temperature to convert the halogenated compounds to olefins and halogenated olefins via elimination reactions.

Farcasiu, Malvina; Kaufman, Phillip B.; Ladner, Edward P.; Anderson, Richard R.

1999-02-26T23:59:59.000Z

391

Panchromatic Photopolymerizable Cationic Films Using Indoline and Squaraine Dye Based Photoinitiating Systems  

Science Journals Connector (OSTI)

The development of novel dyes usable as photoinitiators (PIs) in photoinitiating systems (PISs) of polymerization working under soft visible light irradiations (e.g., household halogen lamps or fluorescent bulbs, household LEDs, sunlight, etc.) is an ongoing challenge attracting great attention in various fields ranging from radiation curing, imaging, and optic technologies to medicine, material science, or microelectronic areas. ... Interestingly, upon very soft LED bulb exposures (?10 mW cm–2), the D102/Iod/NVC combination exhibits good photoinitiating abilities for the cationic polymerization of EPOX under air (Figure 3(a) and Table S1 in the Supporting Information SI; blue LED, FC = 53%; green LED, FC = 51%; tack free coatings), whereas the SQ02/Iod photoinitiating system efficiently initiates the cationic polymerization of DVE-3 in laminate (Figure 3(b) and Table S1 in the Supporting Information; yellow LED, FC = 57%; red LED, FC = 87%; tack free coating). ... Fluorescence quenching rate const. of >60 typical electron donor-acceptor systems, such as fluorescing compds. of 3-pyrenecarboxylic acid (electron acceptor), and naphthalene (electron donor), and quenching compds. of tetracyanoethylene (electron acceptor), and N,N,N',N'-tetramethyl-p-phenylenediamine (electron donor), were measured in MeCN, and are correlated with the free enthalpy change, ?G23, involved in the actual electron transfer process 1F* ... Q ? F.-+. .... Q± (F* is an excited mol., and Q is a non-excited mol.) in the encounter complex, and varying between +5 and -60 kcal/mole. ...

Pu Xiao; Frédéric Dumur; Thanh Tuan Bui; Fabrice Goubard; Bernadette Graff; Fabrice Morlet-Savary; Jean Pierre Fouassier; Didier Gigmes; Jacques Lalevée

2013-07-29T23:59:59.000Z

392

Halogenated Benzimidazole Carboxamides Target Integrin ?4?1 on T-Cell and B-Cell Lymphomas  

Science Journals Connector (OSTI)

...25). Docking simulations Compounds were docked...Nonetheless, molecular modeling studies revealed...Comparative protein modeling by satisfaction...Halliday RS, et al. Automated docking using a...field for molecular simulation of nucleic acids...report focuses on the rapid microwave preparation...

Richard D. Carpenter; Arutselvan Natarajan; Edmond Y. Lau; Mirela Andrei; Danielle M. Solano; Felice C. Lightstone; Sally J. DeNardo; Kit S. Lam; and Mark J. Kurth

2010-07-01T23:59:59.000Z

393

Halogen-driven low-altitude O3 and hydrocarbon losses in spring at northern high latitudes  

E-Print Network (OSTI)

; Vogt et al., 1996; Foster et al., 2001]. HOBr þ Br� þ Hþ ! Br2 þ H2OðR3� HOBr þ Cl� þ Hþ ! BrCl þ H2Oð, National Center for Atmospheric Research, Boulder, Colorado, USA. Copyright 2

Chance, Kelly

394

Kinetic Modeling of Halogen-Based Plasma Etching of Complex Oxide Films and its Application to Predictive Feature Profile Simulation  

E-Print Network (OSTI)

Spectroscopic Diagnostics Of Cf4-O2 Plasmas During Si AndOf Oxygen Additions To Cf4 Plasmas." Journal Of AppliedAnd Silicon Etching Using Cf4 And Chf3." Journal Of Vacuum

Marchack, Nathan

2012-01-01T23:59:59.000Z

395

Preparation, heat capacity, and combustion characteristics of water-surfactant-halogenated hydrocarbon microemulsions suitable for combined fire-extinguishing means  

Science Journals Connector (OSTI)

Water-sodium dodecyl sulfate-triethanolamine-1-pentanol-1,1,2,2-tetrafluorodibromoethane (C2F4Br2) microemulsions differing in the H2O/C2F4Br2 ratio and content of surfactants were prepared. The principal possibi...

D. V. Batov; V. N. Kartsev; S. N. Shtykov

2012-12-01T23:59:59.000Z

396

Application of a Rapid Scanning Plasma Emission Detector and Gas Chromatography for Multi-Element Quantification of Halogenated Hydrocarbons  

Science Journals Connector (OSTI)

......Emission Detector and Gas Chromatography for...element-selective detector for gas chromatography...their insolubility in water, they accumulate...usually quantified by gas chromatographic separation...carbon, oxygen, and nitrogen. This element selective...because of the moderate solubility of this compound......

Mantay Zerezghi; K.J. Mulligan; J.A. Caruso

1984-08-01T23:59:59.000Z

397

Kinetic model for predicting the concentrations of active halogens species in chlorinated saline cooling waters. Final report  

SciTech Connect

A kinetic model has been developed for describing the speciation of chlorine-produced oxidants in seawater as a function of time. The model is applicable under a broad variety of conditions, including all pH range, salinities, temperatures, ammonia concentrations, organic amine concentrations, and chlorine doses likely to be encountered during power plant cooling water chlorination. However, the effects of sunlight are not considered. The model can also be applied to freshwater and recirculating water systems with cooling towers. The results of the model agree with expectation, however, complete verification is not feasible at the present because analytical methods for some of the predicted species are lacking.

Haag, W.R.; Lietzke, M.H.

1981-08-01T23:59:59.000Z

398

Experimental and Computational Study of Flame Inhibition Mechanisms of Halogenated Compounds in C1-C3 Alkanes Flames  

E-Print Network (OSTI)

? = 0.5, (e) Ethane ? = 1.0, (f) Ethane ?=2.0, (g) Propane ? = 0.5, (h) Propane ? = 1.0, (i) Propane ? = 2.0 ............................................................................................ 69 Figure 12. Normalized, peak OH* at near...-atmospheric pressure; (a) Methane ?=0.5, (b) Methane ? = 1.0, (c) Methane ? = 2.0, (d) Ethane ? = 0.5, (e) Ethane ? = 1.0, (f) Ethane ?=2.0, (g) Propane ? = 0.5, (h) Propane ? = 1.0, (i) Propane ? = 2...

Osorio Amado, Carmen H

2013-07-30T23:59:59.000Z

399

Chem 350 Jasperse Ch. 6 Summary of Reaction Types, Ch. 4-6, Test 2 1. Radical Halogenation (Ch. 4)  

E-Print Network (OSTI)

steps. H Br Br · · Br·+ Br Br + H-Br slow step ready to repeat first step 2. SN2 Substitution OCH3 Br SN treatment with Anionic Nucleophile/Base. For 2º alkyl halides, SN2 is often accompanied by variable amounts to Inversion of Configuration Mech: Be able to draw completely. Only one concerted step! OCH3 Br SN2: 1º>2º>3º

Jasperse, Craig P.

400

Environ. Sci. Technol. M92, 26,2454-2461 In-Situ Transformation of Carbon Tetrachloride and Other Halogenated  

E-Print Network (OSTI)

Environ. Sci. Technol. M92, 26,2454-2461 In-Situ Transformation of Carbon Tetrachloride and Other, California 94305-4020 Enhanced in-situ transformation of carbon tetrachloride (CT) was observed under anoxic Chlorinated aliphatic hydrocarbons (CAHs)with one or two carbon atoms are widely used as solvents, degreasing

Semprini, Lewis

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Energy efficient synthesis of boranes  

DOE Patents (OSTI)

The reaction of halo-boron compounds (B--X compounds, compounds having one or more boron-halogen bonds) with silanes provides boranes (B--H compounds, compounds having one or more B--H bonds) and halosilanes. Inorganic hydrides, such as surface-bound silane hydrides (Si--H) react with B--X compounds to form B--H compounds and surface-bound halosilanes. The surface bound halosilanes are converted back to surface-bound silanes electrochemically. Halo-boron compounds react with stannanes (tin compounds having a Sn--H bond) to form boranes and halostannanes (tin compounds having a Sn--X bond). The halostannanes are converted back to stannanes electrochemically or by the thermolysis of Sn-formate compounds. When the halo-boron compound is BCl.sub.3, the B--H compound is B.sub.2H.sub.6, and where the reducing potential is provided electrochemically or by the thermolysis of formate.

Thorn, David L. (Los Alamos, NM); Tumas, William (Los Alamos, NM); Schwarz, Daniel E. (Los Alamos, NM); Burrell, Anthony K. (Los Alamos, NM)

2010-11-23T23:59:59.000Z

402

Energy efficient synthesis of boranes  

DOE Patents (OSTI)

The reaction of halo-boron compounds (B--X compounds, compounds having one or more boron-halogen bonds) with silanes provides boranes (B--H compounds, compounds having one or more B--H bonds) and halosilanes. Inorganic hydrides, such as surface-bound silane hydrides (Si--H) react with B--X compounds to form B--H compounds and surface-bound halosilanes. The surface bound halosilanes are converted back to surface-bound silanes electrochemically. Halo-boron compounds react with stannanes (tin compounds having a Sn--H bond) to form boranes and halostannanes (tin compounds having a Sn--X bond). The halostannanes are converted back to stannanes electrochemically or by the thermolysis of Sn-formate compounds. When the halo-boron compound is BCl.sub.3, the B--H compound is B.sub.2H.sub.6, and where the reducing potential is provided electrochemically or by the thermolysis of formate.

Thorn, David L (Los Alamos, NM); Tumas, William (Los Alamos, NM); Schwarz, Daniel E (Los Alamos, NM); Burrell, Anthony K (Los Alamos, NM)

2012-01-24T23:59:59.000Z

403

Dynamics of Vacuoles and H+-Pyrophosphatase Visualized by Monomeric Green Fluorescent Protein in Arabidopsis: Artifactual Bulbs and Native Intravacuolar Spherical Structures  

Science Journals Connector (OSTI)

...an artifactual fluorescence resonance energy transfer reaction on membranes (Zacharias...reported. In a fluorescence resonance energy transfer assay for membrane proteins...1507-1523. Espiau, B. , Lemercier, G., Ambit, A., Bringaud, F., Merlin, G...

Shoji Segami; Sachi Makino; Ai Miyake; Mariko Asaoka; Masayoshi Maeshima

2014-08-12T23:59:59.000Z

404

Problem 7-3: The air enters with a dry-bulb temperature of 50 o F and, at 50% relative humidity, with a wet-  

E-Print Network (OSTI)

of the power-plant Rankine cycle. The actual process evaporates enough water to increase the humidity ratio. We are now ready to proceed with a cycle calculation, similar to Problem 6-6 P T x h s w q eff · m

405

Systems-Level Analysis of Nitrogen Starvationâ??Induced Modifications of Carbon Metabolism in a Chlamydomonas reinhardtii Starchless Mutant  

Science Journals Connector (OSTI)

...Several observations led to the discovery that...s1, six cool white fluorescent bulbs at 4100K and three warm white fluorescent bulbs at 3000K per incubator...by eight cool white fluorescent bulbs). Metabolite profiles...

Ian K. Blaby; Anne G. Glaesener; Tabea Mettler; Sorel T. Fitz-Gibbon; Sean D. Gallaher; Bensheng Liu; Nanette R. Boyle; Janette Kropat; Mark Stitt; Shannon Johnson; Christoph Benning; Matteo Pellegrini; David Casero; Sabeeha S. Merchant

2013-11-26T23:59:59.000Z

406

Residential and Transport Energy Use in India: Past Trend and Future Outlook  

E-Print Network (OSTI)

type of lighting bulb (incandescent, fluorescent), number ofof incandescent bulbs and fluorescent tubes per household,incandescent bulbs of 60W and 2.1 fluorescent tubes of 40W

de la Rue du Can, Stephane

2009-01-01T23:59:59.000Z

407

ENERGY & ENVIRONMENT DIVISION. ANNUAL REPORT FY 1980  

E-Print Network (OSTI)

lights 100 W bulb to fluorescent (1) Storm windows Centraldamper 100 W bulb to fluorescent (2) R-11 insulationin walls 3-way bulb to fluorescent Caulking Gas range Window

Authors, Various

2010-01-01T23:59:59.000Z

408

Summary of Information and Resources Related to Energy Use in Healthcare Facilities - Version 1  

E-Print Network (OSTI)

57- 57 $YESNO. - FLUOR8 Fluorescent bulbs 59- 59 $YESNO. -CFLR8 Compact fluorescent bulbs 61- 61 $YESNO. - HID8 Highof bulbs 67- 67 $YESNO. - FLUORP8 Percent lit by fluorescent

Singer, Brett C.

2010-01-01T23:59:59.000Z

409

Comparison of Test Procedures and Energy Efficiency Criteria in Selected International Standards and Labeling Programs for Clothes Washers, Water Dispensers, Vending Machines and CFLs  

E-Print Network (OSTI)

top_runner//tr_fluorescent_light_bulb_jul.2009.pdf NiskinSubcommittee Final Report (bulb type fluorescent lamp). ”Fluorescent Lamps (CFLs) are an efficient lighting alternative to traditional incandescent light bulbs

Fridley, David

2010-01-01T23:59:59.000Z

410

502 SHORT COMMUNICATIONS (Speotyto cuniculuria) to a moving object when the  

E-Print Network (OSTI)

the window. A red, 7-watt incandescent bulb inside the box provided illumina- tion for viewing the owl conditions were provided by one and four `I-watt incandescent bulbs, respectively. The single bulb

Minnesota, University of

411

March 10, 2011 Let There Be More Efficient Light  

E-Print Network (OSTI)

standards for light bulbs, which include a phasing out of incandescent bulbs in favor of more energy lyrically with two colleagues about "the incandescent bulb that has been turning back the night ever since

Colorado at Boulder, University of

412

Five Energy-Savings Things I am Thankful for this Year | Department...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

lighting. Energy-efficient light bulbs use 25% to 80% less energy than traditional incandescent bulbs, and they can last 3 to 25 times longer. The right bulb can also offer a...

413

Demand for Environmentally-Friendly Durables  

E-Print Network (OSTI)

the replacement of short-lived incandescent bulbs with long-the replacement of short-lived incandescent bulbs with long-15 watt CFL for 60 watt incandescent bulb), durable (minimum

Martin, Leslie Aimee

2012-01-01T23:59:59.000Z

414

Residential and Transport Energy Use in India: Past Trend and Future Outlook  

E-Print Network (OSTI)

type of lighting bulb (incandescent, fluorescent), number ofhouseholds possessed 3.2 incandescent bulbs of 60W and 2.1areas versus only 2.1 incandescent bulbs of 60W and 1.5

de la Rue du Can, Stephane

2009-01-01T23:59:59.000Z

415

The Influence of Photoperiod History on Circadian Response to Light  

E-Print Network (OSTI)

by broad spectrum white fluorescent bulbs (F4T5) (105 µby broad spectrum white fluorescent bulbs (F4T5) (105 µused broad spectrum white fluorescent bulbs (F4T5) (105 µW/

Glickman, Gena Lynne

416

Characterization of EER4 and SAR1 in Relation to Their Role in Ethylene Signaling and Dampening Responses  

E-Print Network (OSTI)

Sylvania Cool White fluorescent bulbs, Danvers, MA) at 20 oSylvania Gro-Lite fluorescent bulbs, Danvers, MA) at 21 o C

Robles, Linda

2010-01-01T23:59:59.000Z

417

Zinc Oxide and Nitride Nanowire Based Light Emitting Diodes  

E-Print Network (OSTI)

only be able to find incandescent lightbulbs and fluorescent10: Output spectra of incandescent light bulb, fluorescentemission spectra. The incandescent light bulb for example

Lai, Elaine Michelle

2009-01-01T23:59:59.000Z

418

--No Title--  

NLE Websites -- All DOE Office Websites (Extended Search)

alike can also reduce power demand, and thus carbon emissions, by replacing the incandescent bulbs in their homes with energy-saving compact fluorescent bulbs. That's a handy...

419

--No Title--  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

light bulbs, which use 75 percent less energy and last ten times longer than incandescent bulbs, (2) window installation kits, which would improve heat instillation in the...

420

--No Title--  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

out fixtures to accommodate compact fluorescent bulbs instead of relying on incandescent bulbs. Energy Efficiency and Conservation Block Grants Native Village of Stevens...

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

IMPROVING ENERGY EFFICIENCY AND REDUCING COSTS IN THE DRINKING WATER SUPPLY INDUSTRY: An ENERGY STAR Resource Guide for Energy and Plant Managers  

E-Print Network (OSTI)

energy consumed by an incandescent bulb is emitted in thefluorescent (CFL), and incandescent lights typically arelamps in place of incandescent bulbs in most cases; and

Brown, Moya Melody, Camilla Dunham Whitehead, Rich

2011-01-01T23:59:59.000Z

422

Estimate of Cost-Effective Potential for Minimum Efficiency Performance Standards in 13 Major World Economies Energy Savings, Environmental and Financial Impacts  

E-Print Network (OSTI)

lighting, we assume that incandescent bulbs have a one-yeargigaton Indonesia India incandescent Lamp Japan Koreaprice data for 60-watt incandescent bulbs, excluding non-

Letschert, Virginie E.

2013-01-01T23:59:59.000Z

423

General Service LED Lamps | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

DOE SSL technology fact sheet that compares general service LED light bulbs with incandescent and CFL bulbs. ledgeneral-service-lamps.pdf More Documents & Publications LED...

424

CX-000137: Categorical Exclusion Determination | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

out fixtures to accommodate compact fluorescent bulbs instead of relying on incandescent bulbs. DOCUMENT(S) AVAILABLE FOR DOWNLOAD CX-000137.pdf More Documents &...

425

--No Title--  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

the funding permits. Residences for the retrofits will be selected based on need. Incandescent bulbs would be replaced with compact fluorescent bulbs. Power consumption would be...

426

Westinghouse and Fuzhou Permitted to Restart Distribution of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Westinghouse and Fuzhou Permitted to Restart Distribution of Light Bulb Products Westinghouse and Fuzhou Permitted to Restart Distribution of Light Bulb Products August 6, 2010 -...

427

Evaluation of Heat Stress and Strain in Electric Utility Workers  

E-Print Network (OSTI)

Outdoors Wet Bulb Globe Thermometer Equation Equation 3 -Indoors Wet Bulb Globe Thermometer Equation Equation 4 -by a mercury or alcohol thermometer that is shielded from

Brown, Eric Nicholas

2013-01-01T23:59:59.000Z

428

Structural Characterization of and Plutonium Sorption on Mesoporous and Nanoparticulate Ferrihydrite  

E-Print Network (OSTI)

Emission spectrum of the fluorescent light bulbs used in theEmission spectrum of the fluorescent light bulbs used in the

Brogan, Luna Kestrel Schwaiger

2012-01-01T23:59:59.000Z

429

E-Print Network 3.0 - acid hcl solutions Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

Collection: Chemistry 50 HELSINKI UNIVERSITY OF TECHNOLOGY ENE-47.153 Halogens, dioxinsHalogens, dioxinsfuransfurans Summary: -related corrosionChlorine-related corrosion...

430

X-ray haloes and starformation in early-type galaxies  

E-Print Network (OSTI)

High resolution 2D hydrodynamical simulations describing the evolution of the hot ISM in state-of-the-art axisymmetric two-component models of early-type galaxies well reproduced the observed trends of the X-ray luminosity ($L_\\mathrm{x}$) and temperature ($T_\\mathrm{x}$) with galaxy shape and rotation, however they also revealed the formation of an exceedingly massive cooled gas disc in rotating systems. In a follow-up of this study, here we investigate the effects of starformation in the disc, including the consequent injection of mass, momentum and energy in the pre-existing interstellar medium. It is found that subsequent generations of stars originate one after the other in the equatorial region; the mean age of the new stars is $> 5$ Gyr, and the adopted recipe for starformation can reproduce the empirical Kennicutt-Schmidt law. The results of the previous investigation without starformation, concerning $L_\\mathrm{x}$ and $T_\\mathrm{x}$ of the hot gas, and their trends with galactic shape and rotation, ...

Negri, Andrea; Ciotti, Luca

2015-01-01T23:59:59.000Z

431

Probing the intrinsic shape and alignment of dark matter haloes using SDSS galaxy groups  

Science Journals Connector (OSTI)

......projected satellite-central distances of r p 50 kpc. Subsequent studies, however...902. MacGillivray H. T. , Dodd R. J., McNally B. V., Corwin H. G. Jr., 1982, MNRAS, 198, 605. Majewski S. R. , 1994, ApJ, 431, L17. Mandelbaum......

Yougang Wang; Xiaohu Yang; H. J. Mo; Cheng Li; Frank C. Van Den Bosch; Zuhui Fan; Xuelei Chen

432

Ellipticity of dark matter haloes with galaxy–galaxy weak lensing  

Science Journals Connector (OSTI)

......Gunn J. E., Ivezic Z., Knapp G. R., Kent S., Yasuda N., 2001, in Harnden F. R. Jr, Primini F. A., Payne H. E...269. MacGillivray H. T. , Dodd R. J., McNally B. V., Corwin H. G., 1982......

Rachel Mandelbaum; Christopher M. Hirata; Tamara Broderick; Uros Seljak; Jonathan Brinkmann

2006-08-01T23:59:59.000Z

433

Structure of the controlled halo-current magnetic field in the T-10 tokamak  

Science Journals Connector (OSTI)

In the T-10 tokamak, the magnetic field spatially resonant with a ... the cross sections of the torus near the tokamak vacuum vessel wall. The spatial distribution of...

N. V. Ivanov; A. M. Kakurin

2011-01-01T23:59:59.000Z

434

Synthetic Approaches to Skeletally Diverse Sultams Using Vinyl- and ?-Halo Benzenesulfonamides  

E-Print Network (OSTI)

of the corresponding benzothiazepine (n = 1)/benzothiazocine (n = 2) 1,1-dioxides as governing factors in this notable thermodynamic equilibration of atropdiastereomers. Current efforts are focused on the computational calculation for the energy barrier between two...

Jeon, KyuOk

2012-08-31T23:59:59.000Z

435

On the physics of radio haloes in galaxy clusters: scaling relations and luminosity functions  

Science Journals Connector (OSTI)

......emission, Sommer Basu (2013) apply a low-pass filter to the radio data, which minimizes...200 1.4-1014 Mo. If the underlying physics imprinted a characteristic scale into the...in particular gammatu and alphaB (our rate of decline of the magnetic field towards......

Fabio Zandanel; Christoph Pfrommer; Francisco Prada

2014-01-01T23:59:59.000Z

436

Extracting electric dipole breakup cross section of one-neutron halo nuclei from breakup observables  

E-Print Network (OSTI)

How to extract an electric dipole (E1) breakup cross section \\sigma(E1) from one- neutron removal cross sections measured by using 12C and 208Pb targets, \\sigma_(-1n)^C and \\sigma_(-1n)^Pb, respectively, is discussed. It is shown that within about 5% error, \\sigma(E1) can be obtained by subtracting \\Gamma \\sigma_(-1n)^C from \\sigma_(- 1n)^Pb, as assumed in preceding studies. However, for the reaction of weakly-bound projectiles, the scaling factor \\Gamma is found to be two times as large as that usually adopted. As a result, we obtain 13-20% smaller \\sigma(E1) of 31Ne at 250 MeV/nucleon than extracted in a previous analysis of experimental data. By compiling the values of \\Gamma obtained for several projectiles, \\Gamma=(2.30 +/- 0.41)\\exp(- S_n)+(2.43 +/- 0.21) is obtained, where S_n is the neutron separation energy. The target mass number dependence of the nuclear parts of the one-neutron removal cross section and the elastic breakup cross section is also investigated.

Kazuki Yoshida; Tokuro Fukui; Kosho Minomo; Kazuyuki Ogata

2014-07-25T23:59:59.000Z

437

Instrumentation2: Other instruments, ghost/satellite bunch monitoring, halo, emittance, new developments  

E-Print Network (OSTI)

In order to estimate in absolute terms the luminosity of LHC certain beam parameters have to be measured very accurately. In particular the total beam current and the relative distribution of the charges around the ring, the transverse size of the beams at the interaction points and the relative position of the beams at the interaction point. The experiments can themselves measure several of these parameters very accurately thanks to the versatility of their detectors, other parameters need however to be measured using the monitors installed on the machine. The beam instrumentation is usually built for the purpose of aiding the operation team in setting up and optimizing the beams, often this only requires precise relative measurements and therefore the absolute scale is usually not very precisely calibrated. The luminosity calibration requires several machine-side instruments to be pushed beyond their initial scope.

Enrico Bravin; for the CERN BE/BI Collaboration

2011-07-06T23:59:59.000Z

438

MAGICC haloes: confronting simulations with observations of the circumgalactic medium at z = 0  

Science Journals Connector (OSTI)

......maximum velocity of the material in the box is |deltav...ionization). Proper handling of radiative transfer...correspond to optically thin material, i.e. where the...presents three phase diagrams of the CGM material in each galaxy. The......

G. S. Stinson; C. Brook; J. Xavier Prochaska; Joe Hennawi; Sijing Shen; J. Wadsley; Andrew Pontzen; H. M. P. Couchman; T. Quinn; Andrea V. Macciò; Brad K. Gibson

2012-09-11T23:59:59.000Z

439

February 16, 2010 The dark matter halo shape of edge-on disk galaxies  

E-Print Network (OSTI)

@mso.anu.edu.au 2 Kapteyn Astronomical Inst[Bitute, University of Groningen, P.O. Box 800, 9700 AV Groningen

Kruit, Piet van der

440

Thermal instability and the feedback regulation of hot haloes in clusters, groups and galaxies  

Science Journals Connector (OSTI)

......research-article Papers Thermal instability and the feedback...fluid velocity, p is the thermal pressure, e=p...We use a third of the solar metallicity, corresponding...required to maintain thermal equilibrium in the core...strong feedback and can overheat the ICM, as we discuss......

Prateek Sharma; Michael McCourt; Eliot Quataert; Ian J. Parrish

2012-03-11T23:59:59.000Z

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Gas around galaxy haloes: methodology comparisons using hydrodynamical simulations of the intergalactic medium  

Science Journals Connector (OSTI)

......used the DiRAC Data Analytic system at the University of Cambridge, operated by the University of Cambridge High Performance Computing Service on behalf of the STFC DiRAC HPC Facility ( www.dirac.ac.uk ). This equipment was funded by BIS......

Avery Meiksin; James S. Bolton; Eric R. Tittley

2014-01-01T23:59:59.000Z

442

Enlarged Transformation Group: Star Models,Dark Matter Halos and Solar System Dynamics  

E-Print Network (OSTI)

Previously a theory has been presented which extends the geometrical structure of a real four-dimensional space-time via a field of orthonormal tetrads with an enlarged transformation group. This new transformation group, called the conservation group, contains the group of diffeomorphisms as a proper subgroup and we hypothesize that it is the foundational group for quantum geometry. The fundamental geometric object of the new geometry is the curvature vector, C^\\mu . Using the scalar Lagrangian density C^\\mu C_\\mu \\sqrt{-g}, field equations for the free field have been obtained which are invariant under the conservation group. In this paper, this theory is further extended by development of a suitable Lagrangian for a field with sources. Spherically symmetric solutions for both the free field and the field with sources are given. A stellar model and an external, free-field model are developed. The theory implies that the external stress-energy tensor has non-compact support and hence may give the geometrical foundation for dark matter. The resulting models are compared to the internal and external Schwarzschild models. The theory may explain the Pioneer anomaly and the corona heating problem.

Edward Lee Green

2014-07-25T23:59:59.000Z

443

Exploring Halo Substructure with Giant Stars: The Dynamics and Metallicity of the Dwarf Spheroidal in Bootes  

E-Print Network (OSTI)

We report the results of a spectroscopic study of the Bootes (Boo) dwarf spheroidal (dSph) galaxy carried out with the WIYN telescope and the Hydra multifiber spectrograph. Radial velocities have been measured for 58 Boo candidate stars selected to have magnitudes and colors consistent with its red and asymptotic giant branches. Within the 13' half-light radius, seven members of Boo yield a systemic velocity of V_r=95.6+-3.4 km/s and a velocity dispersion of 6.6+-2.3 km/s. This implies a mass on the order of 1 x 10^7 M_sun, similar to the inferred masses of other Galactic dSphs. Adopting a total Boo luminosity of L=1.8 x 10^4 L_sun to 8.6 x 10^4 L_sun implies M/L ~ 610 to 130, making Boo, the most distorted known Milky Way dwarf galaxy, potentially also the darkest. From the spectra of Boo member stars we estimate its metallicity to be [Fe/H] ~ -2.5, which would make it the most metal poor dSph known to date.

Ricardo R. Munoz; Jeffrey L. Carlin; Peter M. Frinchaboy; David L. Nidever; Steven R. Majewski; Richard J. Patterson

2006-06-12T23:59:59.000Z

444

Mergers and Mass Assembly of Dark Matter Halos in a Lambda Cold Dark Matter Universe  

E-Print Network (OSTI)

to EPS . . . . . . . . . . . . . . . . . . . . . . . . .Connection to EPS . . . . . . . . . . . . . . . . . . . .for Consistently Reproducing the EPS Progenitor Mass

Fakhouri, Onsi Joe

2010-01-01T23:59:59.000Z

445

Predicting galaxy star formation rates via the co-evolution of galaxies and haloes  

Science Journals Connector (OSTI)

......New Haven, CT, USA In this paper, we test the age matching hypothesis that the star...quenched and star-forming galaxy samples to test this simple model. We find that our age...et-al. 2002). We have performed such a test (in Papers-I and II as well) and have......

Douglas F. Watson; Andrew P. Hearin; Andreas A. Berlind; Matthew R. Becker; Peter S. Behroozi; Ramin A. Skibba; Reinabelle Reyes; Andrew R. Zentner; Frank C. van den Bosch

2015-01-01T23:59:59.000Z

446

The PN.S Elliptical Galaxy Survey: a standard CDM halo around NGC 4374?  

Science Journals Connector (OSTI)

......the SB profiles. (Note that their Schwarzschild modelling analysis implies a dynamical...data in a sample of ETGs, but using Schwarzschild modelling, Thomas et al. (2007...This apparent DM bimodality may mirror other transitions in ETG properties......

N. R. Napolitano; A. J. Romanowsky; M. Capaccioli; N. G. Douglas; M. Arnaboldi; L. Coccato; O. Gerhard; K. Kuijken; M. R. Merrifield; S. P. Bamford; A. Cortesi; P. Das; K. C. Freeman

2011-03-01T23:59:59.000Z

447

SciTech Connect: Evidence of a halo formation mechanism in the...  

Office of Scientific and Technical Information (OSTI)

Type: Published Article Journal Name: Physical Review Special Topics - Accelerators and Beams Additional Journal Information: Journal Volume: 16; Journal Issue: 4; Journal ID: ISSN...

448

Sequential and spontaneous star formation around the mid-infrared halo H II region KR 140  

Science Journals Connector (OSTI)

......Catalog (2MASS PSC) using the online gator query tool at the Infrared Science Archive...The 2MASS PSC was queried using the gator software at IRSA. All of the catalogue...A-D][A-D][A-D] in sql used by gator. This research has made extensive use......

C. R. Kerton; K. Arvidsson; Lewis B. G. Knee; C. Brunt

2008-04-01T23:59:59.000Z

449

Wide-Field Kinematic Structure of Early-Type Galaxy Halos  

E-Print Network (OSTI)

de Zeeuw, P. T. , Falc´ on- Barroso, J. , Krajnovi´c, D. ,T. , Emsellem, E. , Falc´ on- Barroso, J. , Kuntschner, H. ,Bl´ azquez, P. , Falc´ on-Barroso, J. , Cenarro, A. J. ,

Arnold, Jacob Antony

2013-01-01T23:59:59.000Z

450

The Halo in the Ricefield and the Spectre of the Brocken  

Science Journals Connector (OSTI)

... sunk out of sight, the small portion remaining was suggestive of the lid of a teapot with a knob on top. Some lines of light cloud about the horizon showed ...

ALICE EVERETT

1913-01-23T23:59:59.000Z

451

An ancient F-type subdwarf from the halo crossing the Galactic plane  

E-Print Network (OSTI)

AIMS: We selected the bluest object, WISE~J0725$-$2351, from Luhman's new high proper motion (HPM) survey based on observations with the Wide-field Infrared Survey Explorer (WISE) for spectroscopic follow-up observations. Our aim was to unravel the nature of this relatively bright ($V$$\\sim$12, $J$$\\sim$11) HPM star ($\\mu$$=$267\\,mas/yr). METHODS: We obtained low- and medium-resolution spectra with the European Southern Observatory (ESO) New Technology Telescope (NTT)/EFOSC2 and Very Large Telescope (VLT)/XSHOOTER instruments, investigated the radial velocity and performed a quantitative spectral analysis that allowed us to determine physical parameters. The fit of the spectral energy distribution based on the available photometry to low-metallicity model spectra and the similarity of our target to a metal-poor benchmark star (HD~84937) allowed us to estimate the distance and space velocity. RESULTS: As in the case of HD~84937, we classified WISE~J0725$-$2351 as sdF5: or a metal-poor turnoff star with $[Fe/H]...

Scholz, R -D; Heuser, C; Ziegerer, E; Geier, S; Niederhofer, F

2015-01-01T23:59:59.000Z

452

Studies of Emittance Growth and Halo Particle Production in Intense Charged Particle Beams  

E-Print Network (OSTI)

-gradient transport systems. · Applications: Accelerator systems for high energy and nuclear physics applications and Phase Advance Characterize the Motion ­ Emittance is a Measure of Beam Quality Here, the vacuum phase

Gilson, Erik

453

THE SCATTERED X-RAY HALO AROUND NOVA CYGNI 1992: TESTING A MODEL FOR INTERSTELLAR DUST  

E-Print Network (OSTI)

and Jonathan C. Tan Princeton University Observatory, Peyton Hall, Princeton, NJ 08544; draine@astro.princeton.edu, jt@astro.princeton.edu Received 2002 August 15; accepted 2003 May 13 ABSTRACT We use published ROSAT of emission from an O-Ne white dwarf plus a thermal plasma, and X-ray scattering is calculated for a dust

Draine, Bruce T.

454

Probing the shape and history of the Milky Way halo with orbital spectral analysis  

Science Journals Connector (OSTI)

......simulation was first reported. Run name r 200 (kpc) M 200 (1012...1011 Mo) f b t g (Gyr) Run description Reference SNFWD...parallel N-body+SPH code gasoline (Wadsley, Stadel Quinn 2004...since such orbits populate straight lines on such a map. The strength......

Monica Valluri; Victor P. Debattista; Thomas R. Quinn; Rok Roskar; James Wadsley

2012-01-21T23:59:59.000Z

455

A High Resolution Study of the Halo Nucleus 6 He using  

E-Print Network (OSTI)

by the Edinburgh, TË?ubingen and Glasgow university nuclear physics groups at the Institut fË?ur Kernphysik, Mainz # , 100 # , 125 # and 150 # . The experimental setup allowed the excitation enery of the residual nucleus . . . . . . . . . . . . . . . . . . 3 1.2.4 Current Experiment . . . . . . . . . . . . . . . . . . 6 1.3 Nuclear Structure

Edinburgh, University of

456

Neutrino halos in clusters of galaxies and their weak lensing signature  

SciTech Connect

We study whether non-linear gravitational effects of relic neutrinos on the development of clustering and large-scale structure may be observable by weak gravitational lensing. We compute the density profile of relic massive neutrinos in a spherical model of a cluster of galaxies, for several neutrino mass schemes and cluster masses. Relic neutrinos add a small perturbation to the mass profile, making it more extended in the outer parts. In principle, this non-linear neutrino perturbation is detectable in an all-sky weak lensing survey such as EUCLID by averaging the shear profile of a large fraction of the visible massive clusters in the universe, or from its signature in the general weak lensing power spectrum or its cross-spectrum with galaxies. However, correctly modeling the distribution of mass in baryons and cold dark matter and suppressing any systematic errors to the accuracy required for detecting this neutrino perturbation is severely challenging.

Villaescusa-Navarro, Francisco; Peña-Garay, Carlos [IFIC, Universidad de Valencia-CSIC, E-46071, Valencia (Spain); Miralda-Escudé, Jordi [Institució Catalana de Recerca i Estudis Avançats, Passeig Lluís Companys, 23, 08010-Barcelona (Spain); Quilis, Vicent, E-mail: villa@ific.uv.es, E-mail: miralda@icc.ub.es, E-mail: penya@ific.uv.es, E-mail: vicent.quilis@uv.es [Departamento de Astronomia y Astrofísica, Universidad de Valencia, C/ Dr. Moliner, 50, E-46100, Burjassot, Valencia (Spain)

2011-06-01T23:59:59.000Z

457

RPI students supporting education outreach Target Audience: Elementary school students (grades 3-6)  

E-Print Network (OSTI)

Introduction and Bulb Comparison; LED, Compact Fluorescent, Incandescent Bulb Comparison #12;Resistor Kit (incl (top position), compact fluorescent (middle position), LED Bulb (lower position). Computer set up_12605_SPM2157487603P?pr dNo=16&blockNo=41&blockType=G41 Approx. $9.37 LED Bulb 40 Lumen equivalent (Sylvania

Linhardt, Robert J.

458

GREEN PURCHASING GUIDE THE FOLLOWING PRODUCTS CAN BE FOUND ON W.B. MASON'S GREEN PRODUCTS PAGE AND HAVE BEEN SELECTED BY THE CAMPUS  

E-Print Network (OSTI)

COMPOSTABLE COMPOSTABLE COMPOSTABLE HYPERLINK LIGHT BULBS **ALL COMPACT FLUORESCENT (CFL) AND LED LIGHT BULBS OF BULBS PROPERLY. THE LED BULBS FROM WB MASON ARE SIGNIFICANTLY (5-6X) MORE EXPENSIVE THAN THOSE FOUND AT HARDWARE STORES** INCANDESCENT WATTAGE CFL EQUIVALENT LED EQUIVALENT 40 W 9-13 W 6-8 W60 W 13-15 W 75 W 18

Massachusetts at Amherst, University of

459

HYDROPONIC VEGETABLE GARDENING Marcy Stanton, Master Gardener  

E-Print Network (OSTI)

and a water source. Lighting: A simple 2-bulb 4-foot fluorescent fixture with standard COOL WHITE bulbs is adequate for most leafy vegetables. Do not buy any of the fancy fluorescent grow bulbs; you are wasting your money on these expensive bulbs. When we set up a fluorescent light system to grow vegetables, what

New Hampshire, University of

460

Nitrogen, Aerosol Composition, and Halogens on a Tall Tower (NACHTT): Overview of a wintertime air chemistry field study in the front range urban corridor of Colorado  

E-Print Network (OSTI)

continuous vertical pro?ling and low surface wind speeds. [campaign. (b) Wind speed at 300 m. Vertical pro?ling was not

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "halogen bulbs halo" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

K. Toyota et al.: Photochemistry of VOCs and halogens in the MBL (Supplement) 1 A supplement to "A box model study on photochemical interactions  

E-Print Network (OSTI)

J/mol and of negligible importance at atmospheric temperatures (Kaiser and Wallington, 1996a): Cl + C2H4 HCl + C2H3. (2 occurring in the reaction chamber, Wallington et al. (1990) de- rived the rate constant for Reaction (4

Meskhidze, Nicholas

462

The influence of a presence of a heavy atom on the spin-spin coupling constants between two light nuclei in organometallic compounds and halogen derivatives  

SciTech Connect

The {sup 1}J{sub CC} and {sup 1}J{sub CH} spin-spin coupling constants have been calculated by means of density functional theory (DFT) for a set of derivatives of aliphatic hydrocarbons substituted with I, At, Cd, and Hg in order to evaluate the substituent and relativistic effects for these properties. The main goal was to estimate HALA (heavy-atom-on-light-atom) effects on spin-spin coupling constants and to explore the factors which may influence the HALA effect on these properties, including the nature of the heavy atom substituent and carbon hybridization. The methods applied range, in order of reduced complexity, from Dirac-Kohn-Sham method (density functional theory with four-component Dirac-Coulomb Hamiltonian), through DFT with two- and one-component Zeroth Order Regular Approximation (ZORA) Hamiltonians, to scalar non-relativistic effective core potentials with the non-relativistic Hamiltonian. Thus, we are able to compare the performance of ZORA-DFT and Dirac-Kohn-Sham methods for modelling of the HALA effects on the spin-spin coupling constants.

Wody?ski, Artur; Pecul, Magdalena, E-mail: mpecul@chem.uw.edu.pl [Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warszawa (Poland)] [Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warszawa (Poland)

2014-01-14T23:59:59.000Z

463

Grant Holder Research Organisation Project Title Grant Reference Peter Bernath University of York Satellite Observations of Halogen-Containing Molecules NE/I022663/1  

E-Print Network (OSTI)

, Ice and Super-cooled Water Particles. NE/I023058/1 Gareth Chisham NERC British Antarctic Survey Quantifying the Effect of the Upper Atmospheric Electric Potential on Lower Atmospheric Temperature Orography) NE/I024984/1 Peter Jan van Leeuwen University of Reading Next generation Numerical Weather

464

EDDY RESOLVING NUTRIENT ECODYNAMICS IN THE GLOBAL PARALLEL OCEAN PROGRAM AND CONNECTIONS WITH TRACE GASES IN THE SULFUR, HALOGEN AND NMHC CYCLES  

SciTech Connect

Ecodynamics and the sea-air transfer of climate relevant trace gases are intimately coupled in the oceanic mixed layer. Ventilation of species such as dimethyl sulfide and methyl bromide constitutes a key linkage within the earth system. We are creating a research tool for the study of marine trace gas distributions by implementing coupled ecology-gas chemistry in the high resolution Parallel Ocean Program (POP). The fundamental circulation model is eddy resolving, with cell sizes averaging 0.15 degree (lat/long). Here we describe ecochemistry integration. Density dependent mortality and iron geochemistry have enhanced agreement with chlorophyll measurements. Indications are that dimethyl sulfide production rates must be adjusted for latitude dependence to match recent compilations. This may reflect the need for phytoplankton to conserve nitrogen by favoring sulfurous osmolytes. Global simulations are also available for carbonyl sulfide, the methyl halides and for nonmethane hydrocarbons. We discuss future applications including interaction with atmospheric chemistry models, high resolution biogeochemical snapshots and the study of open ocean fertilization.

S. CHU; S. ELLIOTT

2000-08-01T23:59:59.000Z

465

Fluid origins, paths, and fluid-rock reactions at convergent margins, using halogens, Cl stable isotopes, and alkali metals as geochemical tracers  

E-Print Network (OSTI)

Carbonate chimneys with brucite, blue amphiboles, phengite,partition coefficients. One brucite sample separated from ahigh ? 37 Cl value in the brucite separate sample probably

Wei, Wei

2007-01-01T23:59:59.000Z

466

I/I ratios and halogen concentrations in pore waters of the Hydrate Ridge: Relevance for the origin of gas hydrates in ODP Leg 204  

E-Print Network (OSTI)

in fluids associated with hydrocarbons, such as oil field brines (Moran et al., 1995) or coal-bed methane association of iodine with methane allows the identification of the organic source material responsible for iodine and methane in gas hydrates. In all cores, iodine concentrations were found to increase strongly

Fehn, Udo

467

Volatile Halogenated Hydrocarbons in River Water, Ground Water, Drinking Water and Swimming-Pool Water in the Federal Republic of Germany  

Science Journals Connector (OSTI)

With increasing shortage of ground water it becomes more and more necessary to use surface water as a resource for drinking water and swimming-pool water preparation. In the judgement of water...

M. Sonneborn; S. Gerdes; R. Schwabe

1982-01-01T23:59:59.000Z

468

Comparative Study of Sample Preparation Techniques Coupled to GC for the Analysis of Halogenated Acetic Acids (HAAs) Acids in Tap Water  

Science Journals Connector (OSTI)

......SPE was studied as a possible alternative to LLE for the analysis of...was passed through the SPE car- tridge without a vacuum system...ization conditions were: ion energy 70 eV and mass range 10 to...dure can be proposed as an alternative accu- rate method for the......

Sadia Waseem; Md. Pauzi Abdullah

2010-03-01T23:59:59.000Z

469

Electronic structure and models of monooxygenase inductor receptor from a number of polychlorinated polycyclic compounds. 5. MNDO calculations of halogen derivatives of azoxybenzenes  

Science Journals Connector (OSTI)

The MNDO method has been used to calculate the electronic and geometric structure of 3,3?,4,4?-tetraehloroazoxybenzene (TCAOB), 3,3?,4,4?-tetrachloro-6-hydroxyazobenzene (TCHAB), and 2,3,7,8-tetrachlorodibenzo...

A. V. Fokin; E. B. Bogachuk; N. P. Vorob'eva…

1991-01-01T23:59:59.000Z

470

Electronic structure and models of receptor of monooxygenase inductors from a number of polychlorinated polycyclic compounds. IV. MNDO calculations of halogen-substituted azobenzenes  

Science Journals Connector (OSTI)

The electron and geometric structures of the cis and trans isomers of 3,3?,4,4?-tetrachloroazobenzene (3,3?,4,4?-TCAB) and the trans isomers of 3,3?,5,5?-TCAB and 3,3?-dichloro-4,4?-difluoroazobe...

A. V. Fokin; E. B. Bogachuk; N. I. Raevskii…

1990-08-01T23:59:59.000Z

471

This Month on Energy Savers: February 2011 | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

This Month on Energy Savers: February 2011 This Month on Energy Savers: February 2011 This Month on Energy Savers: February 2011 March 1, 2011 - 8:54am Addthis Allison Casey Senior Communicator, NREL It's still a bit early for spring, but we at Energy Savers have major spring fever. We're pretty sure the rest of the country does, too, after a winter where all 50 states had at least some snow on the ground (and some of you had-or still have-much, much more than others!). So we're thinking spring and bidding a fond farewell (good riddance?) to February and a hearty hello to March. Here's a look back at what happened this month: New or Noteworthy on Energy Savers Did you know that upgrading 15 of the inefficient incandescent light bulbs in your home could save you about $50 per year. New lighting standards take effect in 2012, and money-saving options such as halogen

472

The translucency of dental composites investigated by UV-VIS spectroscopy  

SciTech Connect

Translucency is the property of a material to partially transmit and diffuse incident light, and can be described as a partial opacity or a state between complete opacity and complete transparency. The purpose of this study is to evaluate the translucency index of resin composites according to their chemical structure and to the light source used for curing. Our study was achieved on four commercial composite samples (30 mm × 2 mm) cured with two different lamps (Optilux - halogen bulb and Ultralight - LED). Measurements were made with a UV-VIS spectrophotometer, and the reflection spectrum was recorded in the 380-770 nm region on white and black, compared with a SPECTRALON standard white. For all materials cured with the LED lamp on the glossy sides, the best results were given by Tetric Evo Ceram followed by Filtek Supreme, Restacril{sup RO} and Premise. The measurements made on samples cured with an Optilux lamp, to the smooth and rough sides of the samples, revealed that the highest index of translucency is provided by Tetric Evo Ceram on the smooth side, followed by Filtek Supreme, Restacril{sup RO} and Premises. We can say that the translucency of the composites is mostly determined by the chemical composition of the material, which is observed from transmittance values recorded for each sample, and by the source of radiation applied on the sample.

Dumitrescu, L. Silaghi [Babes Bolyai University -Raluca Ripan Chemistry Research Institute, Cluj-Napoca (Romania)] [Babes Bolyai University -Raluca Ripan Chemistry Research Institute, Cluj-Napoca (Romania); Pastrav, O. [Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca (Romania)] [Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca (Romania); Prejmerean, C.; Prodan, D.; Boboia, S.; Codruta, S.; Moldovan, M. [Babes Bolyai University - Raluca Ripan Chemistry Research Institute, Cluj-Napoca (Romania)] [Babes Bolyai University - Raluca Ripan Chemistry Research Institute, Cluj-Napoca (Romania)

2013-11-13T23:59:59.000Z

473

New Lighting Fixtures: Combining Creativity and Style with Energy Efficiency  

SciTech Connect

This article for a building trade magazine describes a national design competition for energy efficient lighting sponsored by the U.S. Department of Energy, the American Lighting Association, and the Consortium for Energy Efficiency, with winners announced at ALA's Annual Conference May 14, 2004, in Tucson. The Lighting for Tomorrow competition was the first national lighting fixture design competition focusing on energy-efficient residential lighting. The competition invited fixture manufacturers and designers to come up with beautiful, functional lighting fixtures that also happen to be energy efficient. Fixtures were required to use a ''dedicated'' energy-efficient light source, such as a pin-based fluorescent lamp that cannot be replaced with a screw-in incandescent bulb. Fixtures also had to meet a minimum energy efficiency level that eliminated use of incandescent and halogen lamps, leaving the door open only to fluorescent sources and LEDs. More than 150 paper designs were submitted in the first phase of the competition, in 2003. Of those, 24 finalists were invited to submit working prototypes in 2004, and the winners were announced in May. The Grand Prize of $10,000 went to American Fluorescent of Waukegan, Illinois, for its ''Salem'' chandelier. Some winning fixtures are already available through Lowe's Home Improvement Centers.

Gordon, Kelly L.; Foster, Rebecca; McGowan, Terry

2004-10-01T23:59:59.000Z

474

Design and Predictive Control of a Net Zero Energy Home  

E-Print Network (OSTI)

the same amount of light as traditional incandescent bulbs with less energy. Incandescent bulbs are inherently inefficient as most of the energy they consume goes towards heat generation. Compact fluorescent (CFL) and light emitting diode (LED) bulbs... as heat [1]. Compact fluorescent lamps (CFLs) and Light Emitting Diodes (LEDs) were analyzed in comparison with incandescent lamps. To determine the most energy efficient bulb, energy consumption for each type of bulb is needed. To do this, the amount...

Morelli, F.; Abbarno, N.; Boese, E.; Bullock, J.; Carter, B.; Edwards, R.; Lapite, O.; Mann, D.; Mulvihill, C.; Purcell, E.; Stein, M. IV; Rasmussen, B. P.

2013-01-01T23:59:59.000Z

475

Development of Synthetic Phenol from Benzene Halides1  

Science Journals Connector (OSTI)

William J. Hale , Edgar C. Britton ... Halogen-Containing Hydrocarbons from Petroleum and Natural Gas ...

William J. Hale; Edgar C. Britton

1928-01-01T23:59:59.000Z