Sample records for tuesday ray lahood

  1. TODAY: Secretary Chu, Secretary LaHood, Colorado Governor Hickenlooper...

    Energy Savers [EERE]

    TODAY: Secretary Chu, Secretary LaHood, Colorado Governor Hickenlooper, St. Paul Mayor Coleman, Tucson Mayor Walkup to Discuss Success of DOE's Clean Cities Program TODAY:...

  2. Tuesday, February 5 Matei Varga

    E-Print Network [OSTI]

    Grishok, Alla

    Tuesday, February 5 6:00 p.m. Matei Varga Piano Matei Varga (renown Romanian pianist), Iulia Marin 201 Tuesday, February 5 6:00 p.m. Matei Varga Piano Matei Varga (renown Romanian pianist), Iulia Marin

  3. October 2014 Natural Phenomena Hazards (NPH) Meeting - Tuesday...

    Office of Environmental Management (EM)

    Tuesday, October 21st Session Presentations October 2014 Natural Phenomena Hazards (NPH) Meeting - Tuesday, October 21st Session Presentations Presentations Relative Movements for...

  4. An almost introduction Tuesday, March 12, 2013

    E-Print Network [OSTI]

    Baldan, Paolo

    ORC An almost introduction Tuesday, March 12, 2013 #12;Aims · A concurrent language should. · Site returns at most one value. · The value is published. Tuesday, March 12, 2013 #12;ORC programs · Orc program has · a set of definitions · a goal expression · The goal expression is executed. · Its

  5. Fermilab Today Tuesday, June 2, 2009

    E-Print Network [OSTI]

    Fermilab Today Tuesday, June 2, 2009 Calendar Have a safe day! Tuesday, June 2 Noon Summer Lecture Series - Curia II Speaker: Pier Oddone, Fermilab Title: Future of Fermilab THERE WILL BE NO ACCELERATOR-Over THERE WILL BE NO FERMILAB COLLOQUIUM TODAY Click here for NALCAL, a weekly calendar with links to additional information

  6. Condensed Matter Theory Center Tuesday, December 13

    E-Print Network [OSTI]

    Lathrop, Daniel P.

    Condensed Matter Theory Center Seminar Tuesday, December 13 11:00am-12:30pm 2205 Physics Building" Abstract: At sufficiently low temperatures, condensed-matter systems tend to develop order. An notable

  7. Lecture 3 Tuesday, July 3 Francesco Battaglia

    E-Print Network [OSTI]

    Gruen, Sonja

    Lecture 3 Tuesday, July 3 Francesco Battaglia The Cognitive and Systems Neuroscience group effects on the temporal dynamics of hippocampal assemblies. #12;REFERENCES Battaglia FP, Benchenane K, Battaglia FP, Wiener SI (2010) Coherent theta oscillations and reorganization of spike timing

  8. Tuesday,

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |Energy Usage »of EnergyThe EnergyDepartment7Department ofDepartmentEngagingDecember 28,

  9. Tuesday,

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |Energy Usage »of EnergyThe EnergyDepartment7Department ofDepartmentEngagingDecember

  10. TUESDAY: Energy Secretary Moniz to Visit Los Alamos and Sandia...

    Broader source: Energy.gov (indexed) [DOE]

    Energy Secretary Moniz to Visit Los Alamos and Sandia National Laboratories in New Mexico with Senator Udall, Senator Heinrich, and Representative Lujan TUESDAY: Energy...

  11. October 21, Tuesday "Studies on Physical and Chemical Properties of Solids using Porous Materials"

    E-Print Network [OSTI]

    Woodall, Jerry M.

    . Discher Biophysical Engineering Laboratory, University of Pennsylvania December 9, Tuesday 3D Printing

  12. WCROC Organic Dairy Day Tuesday, August 13, 2013

    E-Print Network [OSTI]

    Blanchette, Robert A.

    -876-8636. Printed on recycled and recyclable paper with at least 10 percent postconsumer waste material. All rightsWCROC Organic Dairy Day Tuesday, August 13, 2013 West Central Research and Outreach Center,Morris, MN SEMINARS AND PASTURE TOURS 10AM TO 3PM WCROC Organic Dairy Day Tuesday, August 13, 2013 West

  13. Tuesday Opening Address | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |Energy Usage »of EnergyThe EnergyDepartment7Department ofDepartment of EnergyTuesday

  14. Tesla Demonstration for Happy Valley Elementary Tuesday, November 20th

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Tesla Demonstration for Happy Valley Elementary Tuesday, November 20th Schedule Load Time: 11: ___________________________________________________________ Contact: Chris McGriff, cmcgriff@santacruz.k12.ca.us Address: Happy Valley Elementary School, Branciforte

  15. SUNDAY MONDAY TUESDAY WEDNESDAY THURSDAY FRIDAY SATURDAY Westcott Art Trail

    E-Print Network [OSTI]

    Mather, Patrick T.

    June 2013 SUNDAY MONDAY TUESDAY WEDNESDAY THURSDAY FRIDAY SATURDAY 1 Westcott Art Trail 2 3 4 5 6 7 8 Westcott Art Trail Syracuse Chiefs Game Taste of Syracuse Syracuse Chiefs Game Taste of Syracuse: 10:00 AM ­ 6:00 PM MAY-NOVEMBER WESTCOTT ART TRAIL 10 AM - 5 PM SAT & SUN HTTP

  16. MONDAY TUESDAY WEDNESDAY THURSDAY FRIDAY SATURDAY SUNDAY Boot Camp Circuit

    E-Print Network [OSTI]

    Sharp, Kim

    MONDAY TUESDAY WEDNESDAY THURSDAY FRIDAY SATURDAY SUNDAY Boot Camp Circuit 12:00pm-12:50pm Adarell Body Pump 7:30am­8:30am Nina Boot Camp Circuit 8:00am­8:50am Adarell Body Pump 7:15am-8:15am Carla Body

  17. UK Red Squirrel Group Minutes Tuesday 15th

    E-Print Network [OSTI]

    UK Red Squirrel Group Minutes Tuesday 15th January 2013 1 Welcome and apologies S Bailey Attendee for protocol on red squirrel translocations to SM ­ see renewed AP1 AP2 ALL to visit new RSNE website to BM - complete General consensus that veterinary checks were required for red squirrel translocations

  18. Academic Science Program Task Force Tuesday, September 13, 2011

    E-Print Network [OSTI]

    Academic Science Program Task Force Tuesday, September 13, 2011 3:00 p.m. Nelson Hall, Room 3220 on the Academic Science Program Task Force to Council of Deans on Thursday, September 22, 2011 Margery has been, September 28, 2011 in Witherspoon Cinema from 3-4 p.m. and topics will include budget, strategic plan

  19. Tuesday, March 14, 2006 POSTER SESSION I: MERCURY

    E-Print Network [OSTI]

    Rathbun, Julie A.

    Tuesday, March 14, 2006 POSTER SESSION I: MERCURY 7:00 p.m. Fitness Center Helbert J. Moroz L. V for the MERTIS Instrument on the ESA BepiColombo Mission to Mercury [#1662] The MERTIS instrument on BepiColombo will study the surface of Mercury in the TIR. We will present a list of analog material compiled to support

  20. MAPS Executive Board Meeting Tuesday March 5 2013

    E-Print Network [OSTI]

    Hitchcock, Adam P.

    MAPS Executive Board Meeting Tuesday March 5 2013 MAPS Boardroom, MUSC rm 234. Call to order @5, unanimous 2. Action Items from minutes - MAPS Legal Issues - Andrew reported to the board - Last bill 11.5 k ­ Website ­ how to upload changes - MAPS email signatures - Vehicle - in parking lot ­ must do something

  1. WCROC Organic Dairy Day Tuesday, August 13, 2013

    E-Print Network [OSTI]

    Blanchette, Robert A.

    at 8008768636. Printed on recycled and recyclable paper with at least 10 percent postconsumer waste materialWCROC Organic Dairy Day Tuesday, August 13, 2013 West Central Research and Outreach Center. For More Information Contact: Brad Heins, 3205891711 or hein0106@umn.edu WCROC Organic Dairy Day

  2. WVGEC -January 2012 Sunday Monday Tuesday Wednesday Thursday Friday Saturday

    E-Print Network [OSTI]

    Mohaghegh, Shahab

    WVGEC - January 2012 Sunday Monday Tuesday Wednesday Thursday Friday Saturday 1 2 3 4 5 6 7 New://www.wvu.hsc. edu/charleston/ wvgec Current as of revision date: 12/06/11 #12;WVGEC ­ February 2012 Sunday Monday Literacy Training Program, Bridgeport, WV 5 6 7 8 9 10 11 Friends of Geriatrics (FOG) 3:00PM;HSC 3292 12 13

  3. Introduction Idealized Moist Jet/Front Waves Ray Tracing Momentum Flux/Forcing Conclusion Gravity Waves

    E-Print Network [OSTI]

    Thompson, Anne

    Introduction Idealized Moist Jet/Front Waves Ray Tracing Momentum Flux/Forcing Conclusion Gravity Waves in Moist Baroclinic Jet-Front Systems Junhong Wei, Fuqing Zhang Department of Meteorology The Pennsylvania State University Tuesday 19th August, 2014 #12;Introduction Idealized Moist Jet/Front Waves Ray

  4. Jefferson Lab to Test its Tornado Siren at 9:45 a.m. Tuesday...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Facility will sound its tornado warning siren at 9:45 a.m. on Tuesday, March 17. This test is being conducted in conjunction with the statewide Tornado Response Drill being...

  5. Condensed Matter Theory Center Seminar Tuesday, October 28 at 11:00 AM

    E-Print Network [OSTI]

    Lathrop, Daniel P.

    Condensed Matter Theory Center Seminar Tuesday, October 28 at 11:00 AM 2205 Physics Building bosons neither condense (and become a superfluid) nor localize (and insulate) at T=0. The system

  6. Dear Participant, Welcome to the symposium `Bioenergy Research within SLU' on Tuesday, September 25, at

    E-Print Network [OSTI]

    Dear Participant, Welcome to the symposium `Bioenergy Research within SLU' on Tuesday, September 25 on the web page of the Research school Bioenergy (http://www.slu.se/sv/forskarskolor/bioenergy/) on Monday

  7. Brown Bag Lunch Tuesday, October 23, 12:15-1:15

    E-Print Network [OSTI]

    Brown Bag Lunch Tuesday, October 23, 12:15-1:15 Open Access: How does it impact teaching Campbell, Kathleen MacKenzie, Glenna Quinn Open Access has been both hailed as the answer to unrestricted

  8. Physics 116A Homework Set #2 Winter 2011 DUE: TUESDAY JANUARY 18, 2011

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Physics 116A Homework Set #2 Winter 2011 DUE: TUESDAY JANUARY 18, 2011 Due to Martin Luther King as they are deposited in my physics department mailbox no later than 5 pm on Wednesday January 19. To receive full

  9. TODAY: Secretary Chu, Secretary LaHood, Colorado Governor Hickenlooper, St.

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of Inspector GeneralDepartment of Energyof theRestoration at YoungSuspect|THE WHITE HOUSE THE0 DATE:August65Paul

  10. Tuesday 27 May 09:30 Philosophy of Cognitive Science. Wednesday 28 May 14:30 Intermediate Philosophy of Physics.

    E-Print Network [OSTI]

    Oxford, University of

    Tuesday 27 May 09:30 Philosophy of Cognitive Science. Wednesday 28 May 14:30 Intermediate Philosophy of Physics. Thursday 29 May 09:30 Ethics. Monday 02 June 09:30 Formal Logic. Tuesday 03 June 09:30 Knowledge and Reality. Friday 06 June 09:30 Early Modern Philosophy. Saturday 07 June 14:30 Philosophy

  11. Tuesday April 12, 8:14 PM LEAD: Japan, EU aim to reach conclusion on ITER by July

    E-Print Network [OSTI]

    Tuesday April 12, 8:14 PM LEAD: Japan, EU aim to reach conclusion on ITER by July (Kyodo) _ (EDS." Earlier in the day, Potocnik met with Japan's Education, Culture, Sports, Science and Technology Minister: UPDATING WITH EU COMMISSIONER'S PRESS CONFERENCE) Japan and the European Union agreed Tuesday to speed up

  12. Tuesday, March 13, 2007 POSTER SESSION I: GALILEAN SATELLITES: GEOLOGY AND MAPPING

    E-Print Network [OSTI]

    Rathbun, Julie A.

    Tuesday, March 13, 2007 POSTER SESSION I: GALILEAN SATELLITES: GEOLOGY AND MAPPING 6:30 p. Geissler P. Jaeger W. Becker T. Crown D. A. Schenk P. Geologic Mapping of the Polar Regions of Io [#1124] This abstract discusses our results from geologic mapping of the polar regions of Jupiter's moon Io using

  13. Tuesday, 31 July, 2012 Rapid radiation belt losses occurring during high speed solar wind stream1

    E-Print Network [OSTI]

    Otago, University of

    Tuesday, 31 July, 2012 1 Rapid radiation belt losses occurring during high speed solar wind stream1 Raita11 Sodankylä Geophysical Observatory, University of Oulu, Sodankylä, Finland12 Abstract. Recent geomagnetic disturbances triggered by the arrival of a Solar14 Wind Stream Interface (SWSI). In the current

  14. Timber Products' Mississippi mill earns formaldehyde certification Tuesday, February 10, 2009 -Modern Woodworking

    E-Print Network [OSTI]

    ., have been certified to meet the California Air Resources Board (CARB) requirements. Timber Products of the California Air Resources Board (CARB). Corinth's designation means that all Timber Products hardwood plywoodTimber Products' Mississippi mill earns formaldehyde certification Tuesday, February 10, 2009

  15. WEEK ONE MONDAY TUESDAY WEDNESDAY THURSDAY FRIDAY MORNING SNACK Fresh fruit with milk or

    E-Print Network [OSTI]

    Mumby, Peter J.

    WEEK ONE MONDAY TUESDAY WEDNESDAY THURSDAY FRIDAY MORNING SNACK Fresh fruit with milk or water to drink. Fresh fruit with milk or water to drink Fresh fruit with milk or water to drink Fresh fruit with milk or water to drink Fresh fruit with milk or water to drink MAIN COURSE Spaghetti Bolognese (minced

  16. Tuesday, September 14, 2010 BACHELOR OF SCIENCE IN CIVIL ENGINEERING (2010)

    E-Print Network [OSTI]

    Carver, Jeffrey C.

    2010-01-01T23:59:59.000Z

    Approved Natural Science 4 CE 121 Introduction to Civil, Construction & Environmental Engineering Semester Introduction to Construction Engineering 3 CE 378 Water Resources Engineering 3 CE 320 Intro to EnvironmentalTuesday, September 14, 2010 BACHELOR OF SCIENCE IN CIVIL ENGINEERING (2010) Freshman Year First

  17. Volume 131, Number 15 tech.mit.edu Tuesday, March 29, 2011 Oldest and Largest

    E-Print Network [OSTI]

    's future is in its youth OPINION, p. 4 EDITORIAl: DININg IS DONE The time now is to learn what lessons we education classes begin tomorrow (Monday/Wednesday classes) and Thursday (Tuesday/Thursday classes with baited breath to see whether Japan's damaged nuclear reactor, Fukushima I, would be the next Chernobyl

  18. Campus Limpertsberg -Tuesday 23 April 2013 Public lecture series: Beckerich on the way to

    E-Print Network [OSTI]

    van der Torre, Leon

    Campus Limpertsberg - Tuesday 23 April 2013 Public lecture series: Beckerich on the way to energy autarchy Science and Citizens meet Challenges of Sustainability Public lecture on Energy: Beckerich on the way to energy autarchy An example in Luxembourg: Beckerich. The transition from the fossil

  19. SEA LEVEL RISE, COASTAL RISK, ADAPTATION OPTIONS TUESDAY, FEBRUARY 27, 2014

    E-Print Network [OSTI]

    SEA LEVEL RISE, COASTAL RISK, ADAPTATION OPTIONS TUESDAY, FEBRUARY 27, 2014 For More Information@odu.edu "Sea Level Rise, Coastal Risk, and Adaptation Options" "Looking at what we know about sea level rise will be explored. A special look will be taken at the Philippines and its situation with sea level rise." Skip

  20. A unique program for horse business owners Tuesdays, February 5 -March 19 (seven weeks)

    E-Print Network [OSTI]

    Goodman, Robert M.

    A unique program for horse business owners Tuesdays, February 5 - March 19 (seven weeks) 6:00pm ­ 9 budgeting plan by the end of the seven-week course. The course is offered by Dr. Carey Williams, Equine@njaes.rutgers.edu, 848-932-3229 $70.00 per person Dinner and Companion workbook included. Equine Business Planning Course

  1. Sent: Tuesday, September 24, 2002 5:52 PM To: comment@bpa.gov

    E-Print Network [OSTI]

    on salmon and the people who depend on them for their livelihood. As discussions about the power supplyRD-0131 Sent: Tuesday, September 24, 2002 5:52 PM To: comment@bpa.gov Subject: Salmon & Power Dear Administrator Wright, I understand that the BPA is undergoing discussions to make changes to power distribution

  2. Psychology 204 Spring 2007. Tuesdays 5 7:30 PM Industrial Psychology & Organizational Development

    E-Print Network [OSTI]

    Sanders, Matthew

    Psychology 204 ­ Spring 2007. Tuesdays 5 ­ 7:30 PM Industrial Psychology & Organizational objective of this course is to provide both a conceptual and an experiential learning environment on topics related to group dynamics and organizational change. The course is intended for business professional

  3. BREA Minutes Meeting Date and Place: Tuesday, Oct. 14, 2014; Building 400, Rm RSB 2

    E-Print Network [OSTI]

    Johnson, Peter D.

    BREA Minutes Meeting Date and Place: Tuesday, Oct. 14, 2014; Building 400, Rm RSB 2 Attendees live in New York State (NYS), you can change your medical plan after the first year i.e., if you in NYS. Our current insurance with CIGNA is through the Lab, which is selfinsured. How long

  4. Mineral and Rock Physics [MR] MR21B MCW:Level 1 Tuesday 0800h

    E-Print Network [OSTI]

    Downs, Robert T.

    Mineral and Rock Physics [MR] MR21B MCW:Level 1 Tuesday 0800h Structural Refinement Studies Kunz, Advanced Light Source MR21B-0018 The Crystal Structure of Diopside at Pressure to 10 Gpa tetrahedra and M1 octahedra to try and understand the observed changes in pyroxenes with changing P, T, and x

  5. MAPS Executive Board Meeting Tuesday, March 19, 2013 @ 16:00 hrs

    E-Print Network [OSTI]

    Hitchcock, Adam P.

    1 MAPS Executive Board Meeting Tuesday, March 19, 2013 @ 16:00 hrs MAPS Boardroom, MUSC rm 234 Call b) Previous MAPS Documents (Emily) o The items in the file includes: Nomination form Standing resolution of memberships By-Laws (Period of Jackie Osterman) Previous MAPS publication o Action: By

  6. MAPS Executive Board Meeting Tuesday, February 26, 2013 @ 4:00pm

    E-Print Network [OSTI]

    Hitchcock, Adam P.

    MAPS Executive Board Meeting Tuesday, February 26, 2013 @ 4:00pm MAPS Boardroom, MUSC rm 234 Call since MAPS by-law (28-a) states that the Secretary shall be the Executive Director of the MAPS. Action: Amend bi-law 28-A 3. Report/discussion items. a) A. Smith has been the primary contact for MAPS

  7. Tuesday, March 24, 2009 POSTER SESSION I: COMET WILD 2: MINERALOGY AND MORE

    E-Print Network [OSTI]

    Rathbun, Julie A.

    Tuesday, March 24, 2009 POSTER SESSION I: COMET WILD 2: MINERALOGY AND MORE 6:30 p.m. Town Center, all material from along the tracks needs to be analyzed. Stodolna J. Jacob D. Leroux H. Mineralogy of a compressed wall piece extracted from track 80. The sample shows a large diversity of mineralogy suggesting

  8. Tuesday, March 24, 2009 POSTER SESSION I: PETROLOGY AND MINERALOGY OF THE SNC METEORITES

    E-Print Network [OSTI]

    Rathbun, Julie A.

    Tuesday, March 24, 2009 POSTER SESSION I: PETROLOGY AND MINERALOGY OF THE SNC METEORITES 6:30 p and Mineralogical Diversities Within the Lherzolitic Shergottites Require a New Group Name? [#2272] "Pyroxene shergottites such as RBT 04262 and NWA 4468 has revealed petrological and mineralogical diversities

  9. Tuesday, March 14, 2006 POSTER SESSION I: AEOLIAN PROCESSES ON MARS: WAR OF THE WHIRLS

    E-Print Network [OSTI]

    Rathbun, Julie A.

    Tuesday, March 14, 2006 POSTER SESSION I: AEOLIAN PROCESSES ON MARS: WAR OF THE WHIRLS 7:00 p, and static thresholds were devised. Lunar and Planetary Science XXXVII (2006) full319.pdf #12;DUNE FORMS.F. Mullins, R. Hayward, K.L. Tanaka, U.S. Geological Survey, Astrogeology Team, 2255 N. Gemini Dr. Flagstaff

  10. Tuesday, July 14th, 2009 Welcome: Kelly Smith My Settings Logout Register Now From this week's Focus

    E-Print Network [OSTI]

    Sherman, S. Murray

    Tuesday, July 14th, 2009 Welcome: Kelly Smith My Settings Logout Register Now From this week-tech, fractured health care system that has evolved over the last two decades has been that medical students

  11. Rostock, September 9-14, 2012 T17: Tuesday 11.09.2012, 11:50 -12:10

    E-Print Network [OSTI]

    Rostock, September 9-14, 2012 T17: Tuesday 11.09.2012, 11:50 - 12:10 Thermonuclear fusion in dense study the plasma correlation effects on nonresonant thermonuclear reactions of carbon and oxygen

  12. KTH Department of Energy Technology Seminar on Tuesday May 22, 2012 at 11:15 * Brinellvgen 68, Stockholm, Sweden

    E-Print Network [OSTI]

    Kostic, Milivoje M.

    KTH Department of Energy Technology Seminar on Tuesday May 22, 2012 at 11:15 * Brinellvägen 68, Stockholm, Sweden Contact Person: Björn Palm, Professor, Head of Department Department of Energy Technology

  13. Date Time Date Time New, renewal, resubmission F Series Fellowships (Individual NRSA) Tuesday, April 8 5:00 pm Wednesday April 2 8:00 am

    E-Print Network [OSTI]

    Williams, Gary A.

    SEES) Tuesday, April 8 5:00 pm Wednesday, April 2 8:00 am CyberPhysical Systems (CPS) Monday June 2 5:00 pm Partnerships for Innovation: Accelerating Innovation Research Technology Translation (PFI: AIRTT) Thursday & Cognition Monday, June 16 5:00 pm Tuesday, June 10 8:00 am Plant Genome Research Program (PGRP) Monday

  14. Date Time Date Time New, renewal, resubmission F Series Fellowships (Individual NRSA) Tuesday, April 8 5:00 pm Wednesday April 2 8:00 am

    E-Print Network [OSTI]

    Williams, Gary A.

    SEES) Tuesday, April 8 5:00 pm Wednesday, April 2 8:00 am Cyber-Physical Systems (CPS) Monday June 2 5:00 pm Partnerships for Innovation: Accelerating Innovation Research - Technology Translation (PFI: AIR-TT) Thursday/Program Description Perception, Action & Cognition Monday, June 16 5:00 pm Tuesday, June 10 8:00 am Plant Genome

  15. Tuesday, sepTember 10 | NooN -1:00p.m. King Hall, Room 1002

    E-Print Network [OSTI]

    California at Davis, University of

    and energy legislation at the Stanford Law School, Berkeley Law, UC Davis School of Law, Loyola Law SchoolEl Moderator: Chris Bowman Communications Director at UC Davis Center for Watershed Sciences; Chairman, and at UC Berkeley, UC Davis, and CSU Sacramento. Tuesday, sepTember 24 | NooN - 1:00p.m. King Hall, Room

  16. energy.gov -Speeches (Print Version) Tuesday, February 4, 2003 http://www.energy.gov/HQDocs/speeches/2003/febss/

    E-Print Network [OSTI]

    threats, and we have reduced the risk of accidents in nuclear fuel cycle facilities worldwide. Thanksenergy.gov - Speeches (Print Version) Tuesday, February 4, 2003 http://www.energy.gov/HQDocs/speeches/2003/febss/ 04BudgetPressConferenceRemarks_v.html Page: 1 Press Conference Remarks Energy Secretary

  17. Groundbreaking for the Djavad Mowafaghian Centre for Brain Health Tuesday, October 11, 2011 --UBC Hospital Parking Lot

    E-Print Network [OSTI]

    Pulfrey, David L.

    Groundbreaking for the Djavad Mowafaghian Centre for Brain Health Tuesday, October 11, 2011 -- UBC. And right here, right now, we are brothers and sisters on this planet, #12;Centre for Brain Health with this Centre for Brain Health: collaboration between UBC's Faculty of Medicine and Vancouver Coastal Health

  18. The Kinematic Wave Equation (KWE) In Tuesday's interrupted lecture we derived the Kinematic Wave Equation (KWE) for a density

    E-Print Network [OSTI]

    Gibbon, J. D.

    The Kinematic Wave Equation (KWE) In Tuesday's interrupted lecture we derived the Kinematic Wave refer to partial derivatives. Kinematic waves occur when we take Q = Q(), in which case t + c()x = 0 (2) where the propagation velocity is c() = dQ/d. (2) is called the Kinematic Wave Equation (KWE). We wish

  19. 47043Federal Register / Vol. 77, No. 152 / Tuesday, August 7, 2012 / Notices 41 See Notice of Antidumping Duty Orders

    E-Print Network [OSTI]

    and Technology Work Group on Measuring Systems for Electric Vehicle Fueling AGENCY: National Institute47043Federal Register / Vol. 77, No. 152 / Tuesday, August 7, 2012 / Notices 41 See Notice and Technology (NIST) is forming a Work Group (WG) to develop proposed requirements for commercial electricity

  20. Tuesday, February 18, 2003 http://www.pppl.gov/ncsx/pvr/pvr.HTML Page: 1 NCSX Home Page

    E-Print Network [OSTI]

    pvr Tuesday, February 18, 2003 http://www.pppl.gov/ncsx/pvr/pvr.HTML Page: 1 NCSX Home Page PVR Chapter 5 - Ideal MHD Stability Chapter 6 - Resistive Stability Chapter 7 - Plasma Heating Chapter 8 VMEC (Steve Hirshman) Power and Particle Control in NCSX (Peter Mioduszewski) NCSX Heating: Neutral

  1. Understanding Energy Models and Modeling (ENV 715) Spring 2013 Tuesday/Thursday 10:05-11:20 am

    E-Print Network [OSTI]

    Ferrari, Silvia

    1 Understanding Energy Models and Modeling (ENV 715) Spring 2013 Tuesday/Thursday 10:05-11:20 am) Course Description and Learning Objectives Energy models are widely used for policy analysis, scenario, however, energy models have their limitations and lend themselves to abuse and misinterpretation. Policy

  2. From: training@ucsf.edu [training@ucsf.edu] Sent: Tuesday, February 26, 2013 10:07 PM

    E-Print Network [OSTI]

    Klein, Ophir

    From: training@ucsf.edu [training@ucsf.edu] Sent: Tuesday, February 26, 2013 10:07 PM To: Name, Employee Subject: UCSF PRIVACY TRAINING ASSIGNED TO EMPLOYEE NAME Employee Name, Welcome to UC San patients. To support this commitment, new employees must complete privacy training. UCSF provides various

  3. 1602 Federal Register / Vol. 76, No. 7 / Tuesday, January 11, 2011 / Notices * An SME is defined as a firm with 500 or fewer

    E-Print Network [OSTI]

    1602 Federal Register / Vol. 76, No. 7 / Tuesday, January 11, 2011 / Notices * An SME is defined,000 for large firms and $2,000 for a small or medium-sized enterprise (SME),* with up to two company

  4. January 14, 2014 Tuesday SORTS Seminar -Time Management ARC 6:00p 7:00p ESB G102 Student Success Seminar Sign In January 16, 2014 Thursday NASA Lecture NASA IV&V 11:00a 12:00p ESB G84 Career Exploration & Planning PreRegister

    E-Print Network [OSTI]

    Mohaghegh, Shahab

    & Planning Form February 11, 2014 Tuesday Current Research - Microhydro turbine design Josh Matheny 5:00p 6

  5. MONDAY TUESDAY WEDNESDAY THURSDAY FRIDAY SATURDAY SUNDAY Boot Camp Butt and Gut Boot Camp Butt and Gut Boot Camp

    E-Print Network [OSTI]

    Dawson, Jeff W.

    MONDAY TUESDAY WEDNESDAY THURSDAY FRIDAY SATURDAY SUNDAY 7:00am Boot Camp Butt and Gut Boot Camp Butt and Gut Boot Camp 7:30am 8:00am Women's Strength Training Program (7-8am) Women's Strength Kickboxing Tabata (12:10-12:50pm) Bands and Buns Step Muscle Mix Cardio Kickbox Boot Camp Core Chisel 12:30pm

  6. FOR RELEASE: 11:00 a.m. PST, Tuesday, January 11, 2005, coordinated with a Press Conference at the American Astronomical Society meeting in San Diego, Ca.

    E-Print Network [OSTI]

    Schaefer, Bradley E.

    FOR RELEASE: 11:00 a.m. PST, Tuesday, January 11, 2005, coordinated with a Press Conference in a press conference today by Prof. Bradley E. Schaefer (Louisiana State University, Baton Rouge of 70 positions on the globe and made a formal mathematical fit to find the best date. This best date

  7. TUESDAY MORNING, 1 JULY 2008 ROOM 250B, 8:20 TO 10:20 A.M. Session 2aSCb

    E-Print Network [OSTI]

    Avanzini, Federico

    TUESDAY MORNING, 1 JULY 2008 ROOM 250B, 8:20 TO 10:20 A.M. Session 2aSCb Speech Communication: How ('Magnet house'), Finland Invited Papers 8:20 2aSCb1. Action-based multisensory integration in striking"or visual. For each of the experimental trials, they initially receive feedback on the tracking

  8. Advanced Econometrics (26:223:655:01) Spring 2008 Meets Tuesdays, 2:30-5:20 PM, GFMC (Ackerson Hall 106)

    E-Print Network [OSTI]

    Lin, Xiaodong

    Advanced Econometrics (26:223:655:01) Spring 2008 Meets Tuesdays, 2:30-5:20 PM, GFMC (Ackerson Hall and generalization of the material covered in Econometrics (26:223:554). The purpose of this course is to develop advanced econometric estimation and hypothesis testing tools to analyze and interpret the empirical

  9. Tuesday, May 28, 2002 Thermometer in Nanotube Page: 1 http://www.nytimes.com/2002/02/12/science/12OBSE.html?pagewanted=print

    E-Print Network [OSTI]

    Rubenstein, Dustin R.

    Tuesday, May 28, 2002 Thermometer in Nanotube Page: 1 http://www.nytimes.com/2002/02/12/science/12OBSE.html?pagewanted=print February 12, 2002 Thermometer in Nanotube By HENRY FOUNTAIN ack in the analog age, a thermometer was a simple thing, just a glass tube containing a column of mercury

  10. The Shorthorn: Casey Crane Robert Arrowood, Carrizo Oil and Gas, Inc. representative, takes local homeowners' questions about on-campus natural gas drilling in an Arlington office complex Tuesday.

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    homeowners' questions about on-campus natural gas drilling in an Arlington office complex Tuesday. Jenna that plans to drill on university property. Carrizo Oil and Gas, Inc. recently signed a one-year lease with the university and called the meeting to alleviate con- cerns about the drilling. They also strived to get

  11. This year's annual technical meeting will be held on Monday and Tuesday. Wednesday is optional and is intended for software demonstrations. We will be at a new meeting location with exceptional food and, as usual, excellent

    E-Print Network [OSTI]

    Torres-Verdín, Carlos

    : consortium status, summary of projects, accomplishments, and deliverables: Carlos Torres-Verdín. 9:00 AM Software status and future developments: Carlos Torres-Verdín. 9:30 AM Break TECHNICAL PRESENTATIONS (Part-17 (Monday, Tuesday and Wednesday), 2011 Center for Petroleum and Geosystems Engineering Department

  12. Gamma Ray Bursts

    E-Print Network [OSTI]

    Stahl, Bennett

    2014-01-01T23:59:59.000Z

    Olson. Observations of gamma-ray bursts of cosmic origin. E. Lingenfelter. Gamma-ray bursts. Annual Review of652-654. Waxman, Eli. Gamma-ray-burst afterglow: supporting

  13. Gamma ray generator

    DOE Patents [OSTI]

    Firestone, Richard B; Reijonen, Jani

    2014-05-27T23:59:59.000Z

    An embodiment of a gamma ray generator includes a neutron generator and a moderator. The moderator is coupled to the neutron generator. The moderator includes a neutron capture material. In operation, the neutron generator produces neutrons and the neutron capture material captures at least some of the neutrons to produces gamma rays. An application of the gamma ray generator is as a source of gamma rays for calibration of gamma ray detectors.

  14. Secretary Chu, Mayor Stanton to Unveil Phase Two of Nation's...

    Office of Environmental Management (EM)

    Link Addthis Related Articles In Arizona, Helping Communities Realize the Promise of Solar Power TODAY: Secretary Chu, Secretary LaHood, Colorado Governor Hickenlooper, St....

  15. 24. Cosmic rays 1 24. COSMIC RAYS

    E-Print Network [OSTI]

    electrons, protons and helium, as well as carbon, oxygen, iron, and other nuclei synthesized in stars) and the intensity of the cosmic rays with energies below about 10 GeV. In addition, the lower-energy cosmic rays the intensity of any component of the cosmic radiation in the GeV range depends both on the location and time

  16. 26. Cosmic rays 1 26. COSMIC RAYS

    E-Print Network [OSTI]

    electrons, protons and helium, as well as carbon, oxygen, iron, and other nuclei synthesized in stars) and the intensity of the cosmic rays with energies below about 10 GeV. In addition, the lower-energy cosmic rays the intensity of any component of the cosmic radiation in the GeV range depends both on the location and time

  17. Ray J. Corey- Biography

    Broader source: Energy.gov [DOE]

    Ray Corey currently serves as the Assistance Manager for Safety and Environment at the DOE Richland Operations office (RL).

  18. X-Ray Data Booklet X-RAY DATA BOOKLET

    E-Print Network [OSTI]

    Meagher, Mary

    X-Ray Data Booklet X-RAY DATA BOOKLET Center for X-ray Optics and Advanced Light Source Lawrence Berkeley National Laboratory Introduction X-Ray Properties of Elements Electron Binding Energies X-Ray Levels of Few Electron Ions Now Available Order X-Ray Data Booklet http://xdb.lbl.gov/ (1 of 3) [2

  19. Gamma-ray Astronomy

    E-Print Network [OSTI]

    Jim Hinton

    2007-12-20T23:59:59.000Z

    The relevance of gamma-ray astronomy to the search for the origin of the galactic and, to a lesser extent, the ultra-high-energy cosmic rays has long been recognised. The current renaissance in the TeV gamma-ray field has resulted in a wealth of new data on galactic and extragalactic particle accelerators, and almost all the new results in this field were presented at the recent International Cosmic Ray Conference (ICRC). Here I summarise the 175 papers submitted on the topic of gamma-ray astronomy to the 30th ICRC in Merida, Mexico in July 2007.

  20. Gamma-ray waveguides

    SciTech Connect (OSTI)

    Tournear, D. M.; Hoffbauer, M. A.; Akhadov, E. A.; Chen, A. T.; Pendleton, S. J.; Williamson, T. L.; Cha, K. C.; Epstein, R. I. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2008-04-14T23:59:59.000Z

    We have developed an approach for gamma-ray optics using layered structures acting as planar waveguides. Experiments demonstrating channeling of 122 keV gamma rays in two prototype waveguides validate the feasibility of this technology. Gamma-ray waveguides allow one to control the direction of radiation up to a few MeV. The waveguides are conceptually similar to polycapillary optics, but can function at higher gamma-ray energies. Optics comprised of these waveguides will be able to collect radiation from small solid angles or concentrate radiation into small area detectors. Gamma-ray waveguides may find applications in medical imaging and treatment, astrophysics, and homeland security.

  1. Tuesday, August 24, 2010

    Broader source: Energy.gov (indexed) [DOE]

    0 X D Hazardous Air Pollutants? Is the project subject to emissions limitations in an Air Quality 0 X D Control Region? 2 Revised 8121 0 mjt NEPA COMPLIANCE SURVEY Impacts If...

  2. Tuesday, October 21, 2008

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2TopoPortalBRDF EffectsPacific: AEnergy

  3. Tuesday, August 14, 2007

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of Inspector GeneralDepartment of Energyof theRestorationAdvisoryManagementTribalSOLARJanuary 27, 2004 0 Part

  4. Tuesday, February 12, 2008

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of Inspector GeneralDepartment of Energyof theRestorationAdvisoryManagementTribalSOLARJanuary 27, 2004 0December

  5. Tuesday, December 04, 2007

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "of EnergyEnergyENERGYWomen Owned SmallOf The 2012 Greenbuy3 Archive DOE-HDBK-1129-2008 DecemberDecember

  6. Tuesday, January 08, 2008

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "of EnergyEnergyENERGYWomen Owned SmallOf The 2012 Greenbuy3 Archive DOE-HDBK-1129-2008

  7. Tuesday, September 11, 2007

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "of EnergyEnergyENERGYWomen Owned SmallOf The 2012 Greenbuy3 Archive DOE-HDBK-1129-2008

  8. Gamma-Ray Bursts

    E-Print Network [OSTI]

    E. Waxman

    2000-04-11T23:59:59.000Z

    Ultra-high-energy, >10^19 eV, cosmic-ray and high energy, ~10^14 eV, neutrino production in GRBs is discussed in the light of recent GRB and cosmic-ray observations. Emphasis is put on model predictions that can be tested with operating and planned cosmic-ray and neutrino detectors, and on the prospects of testing for neutrino properties.

  9. Cosmic Ray Astronomy

    E-Print Network [OSTI]

    Paul Sommers; Stefan Westerhoff

    2008-02-09T23:59:59.000Z

    Cosmic ray astronomy attempts to identify and study the sources of ultrahigh energy cosmic rays. It is unique in its reliance on charged particles as the information carriers. While no discrete source of ultrahigh energy cosmic rays has been identified so far, a new generation of detectors is acquiring the huge exposure that is needed at the highest energies, where deflection by magnetic fields is minimized and the background from distant sources is eliminated by pion photoproduction. In this paper, we summarize the status of cosmic ray astronomy, describing the detectors and the analysis techniques.

  10. Gamma Ray Bursts Sudden, intense flashes of gamma rays

    E-Print Network [OSTI]

    Washington at Seattle, University of - Department of Physics, Electroweak Interaction Research Group

    Gamma Ray Bursts #12;The Case Sudden, intense flashes of gamma rays come from nowhere and disappear with out a trace. Incredibly powerful: A single gamma ray burst is hundreds of times brighter a supernova #12;Who Vela (1960's) Looking for arms testing, found gamma ray bursts Compton Gamma Ray Observatory

  11. X-ray beamsplitter

    DOE Patents [OSTI]

    Ceglio, N.M.; Stearns, D.G.; Hawryluk, A.M.; Barbee, T.W. Jr.

    1987-08-07T23:59:59.000Z

    An x-ray beamsplitter which splits an x-ray beam into two coherent parts by reflecting and transmitting some fraction of an incident beam has applications for x-ray interferometry, x-ray holography, x-ray beam manipulation, and x-ray laser cavity output couplers. The beamsplitter is formed of a wavelength selective multilayer thin film supported by a very thin x-ray transparent membrane. The beamsplitter resonantly transmits and reflects x-rays through thin film interference effects. A thin film is formed of 5--50 pairs of alternate Mo/Si layers with a period of 20--250 A. The support membrane is 10--200 nm of silicon nitride or boron nitride. The multilayer/support membrane structure is formed across a window in a substrate by first forming the structure on a solid substrate and then forming a window in the substrate to leave a free-standing structure over the window. 6 figs.

  12. X-ray beamsplitter

    DOE Patents [OSTI]

    Ceglio, Natale M. (Livermore, CA); Stearns, Daniel S. (Mountain View, CA); Hawryluk, Andrew M. (Modesto, CA); Barbee, Jr., Troy W. (Palo Alto, CA)

    1989-01-01T23:59:59.000Z

    An x-ray beamsplitter which splits an x-ray beam into two coherent parts by reflecting and transmitting some fraction of an incident beam has applications for x-ray interferometry, x-ray holography, x-ray beam manipulation, and x-ray laser cavity output couplers. The beamsplitter is formed of a wavelength selective multilayer thin film supported by a very thin x-ray transparent membrane. The beamsplitter resonantly transmits and reflects x-rays through thin film interference effects. A thin film is formed of 5-50 pairs of alternate Mo/Si layers with a period of 20-250 A. The support membrane is 10-200 nm of silicon nitride or boron nitride. The multilayer/support membrane structure is formed across a window in a substrate by first forming the structure on a solid substrate and then forming a window in the substrate to leave a free-standing structure over the window.

  13. Gamma ray detector shield

    DOE Patents [OSTI]

    Ohlinger, R.D.; Humphrey, H.W.

    1985-08-26T23:59:59.000Z

    A gamma ray detector shield comprised of a rigid, lead, cylindrical-shaped vessel having upper and lower portions with an pneumatically driven, sliding top assembly. Disposed inside the lead shield is a gamma ray scintillation crystal detector. Access to the gamma detector is through the sliding top assembly.

  14. Gamma Ray Bursts

    E-Print Network [OSTI]

    Peter Mszros

    2012-04-12T23:59:59.000Z

    Gamma-ray bursts have been detected at photon energies up to tens of GeV. We review some recent developments in the X-ray to GeV photon phenomenology in the light of Swift and Fermi observations, and some of the theoretical models developed to explain them, with a view towards implications for C.T.A.

  15. Chest x-Rays

    Broader source: Energy.gov [DOE]

    The B-reading is a special reading of a standard chest x-ray film performed by a physician certified by the National Institute for Occupational Safety and Health (NIOSH). The reading looks for changes on the chest x-ray that may indicate exposure and disease caused by agents such as asbestos or silica.

  16. X-ray binaries

    E-Print Network [OSTI]

    H. Schatz; K. E. Rehm

    2006-08-01T23:59:59.000Z

    We review the nuclear astrophysics aspects of accreting neutron stars in X-ray binaries. We summarize open astrophysical questions in light of recent observations and their relation to the underlying nuclear physics. Recent progress in the understanding of the nuclear physics, especially of X-ray bursts, is also discussed.

  17. X-ray absorption spectroscopy

    E-Print Network [OSTI]

    Yano, Junko; Yachandra, Vittal K.

    2009-01-01T23:59:59.000Z

    009-9473-8 REVIEW X-ray absorption spectroscopy Junko Yano and application of X-ray absorption spectroscopy, bothX-ray absorption near-edge structure (XANES) and extended X-

  18. X-ray Absorption Spectroscopy

    E-Print Network [OSTI]

    Yano, Junko

    2010-01-01T23:59:59.000Z

    type: Review X-ray Absorption Spectroscopy Junko Yano andPhotosystem II; XAS, X-ray absorption spectroscopy; EXAFS,X-ray absorption fine structure; EPR, electron paramagnetic

  19. Gamma ray optics

    SciTech Connect (OSTI)

    Jentschel, M.; Guenther, M. M.; Habs, D.; Thirolf, P. G. [Institut Laue-Langevin, F38042 Grenoble (France); Max-Planck-Institut fuer Quantenoptik, D-85748 Garching (Germany); Max-Planck-Institut fuer Quantenoptik, D-85748 Garching, Germany and Ludwig-Maximilians-Universitaet Muenchen, D-85748 Garching (Germany); Ludwig-Maximilians-Universitaet Muenchen, D-85748 Garching (Germany)

    2012-07-09T23:59:59.000Z

    Via refractive or diffractive scattering one can shape {gamma} ray beams in terms of beam divergence, spot size and monochromaticity. These concepts might be particular important in combination with future highly brilliant gamma ray sources and might push the sensibility of planned experiments by several orders of magnitude. We will demonstrate the experimental feasibility of gamma ray monochromatization on a ppm level and the creation of a gamma ray beam with nanoradian divergence. The results are obtained using the inpile target position of the High Flux Reactor of the ILL Grenoble and the crystal spectrometer GAMS. Since the refractive index is believed to vanish to zero with 1/E{sup 2}, the concept of refractive optics has never been considered for gamma rays. The combination of refractive optics with monochromator crystals is proposed to be a promising design. Using the crystal spectrometer GAMS, we have measured for the first time the refractive index at energies in the energy range of 180 - 2000 keV. The results indicate a deviation from simple 1/E{sup 2} extrapolation of X-ray results towards higher energies. A first interpretation of these new results will be presented. We will discuss the consequences of these results on the construction of refractive optics such as lenses or refracting prisms for gamma rays and their combination with single crystal monochromators.

  20. X-Ray Observations of Gamma-Ray Burst Afterglows

    E-Print Network [OSTI]

    Filippo Frontera

    2004-06-25T23:59:59.000Z

    The discovery by the BeppoSAX satellite of X-ray afterglow emission from the gamma-ray burst which occurred on 28 February 1997 produced a revolution in our knowledge of the gamma-ray burst phenomenon. Along with the discovery of X-ray afterglows, the optical afterglows of gamma-ray bursts were discovered and the distance issue was settled, at least for long $\\gamma$-ray bursts. The 30 year mystery of the gamma-ray burst phenomenon is now on the way to solution. Here I rewiew the observational status of the X-ray afterglow emission, its mean properties (detection rate, continuum spectra, line features, and light curves), and the X-ray constraints on theoretical models of gamma-ray bursters and their progenitors. I also discuss the early onset afterglow emission, the remaining questions, and the role of future X-ray afterglow observations.

  1. X-ray laser

    DOE Patents [OSTI]

    Nilsen, Joseph (Livermore, CA)

    1991-01-01T23:59:59.000Z

    An X-ray laser (10) that lases between the K edges of carbon and oxygen, i.e. between 44 and 23 Angstroms, is provided. The laser comprises a silicon (12) and dysprosium (14) foil combination (16) that is driven by two beams (18, 20) of intense line focused (22, 24) optical laser radiation. Ground state nickel-like dysprosium ions (34) are resonantly photo-pumped to their upper X-ray laser state by line emission from hydrogen-like silicon ions (32). The novel X-ray laser should prove especially useful for the microscopy of biological specimens.

  2. Cosmic rays in astrospheres

    E-Print Network [OSTI]

    Scherer, Klaus; Bomans, Dominik; Ferreira, Stefan; Fichtner, Horst; Kleimann, Jens; Strauss, Dutoit; Weis, Kerstin; Wiengarten, Tobias; Wodzinski, Thomas

    2015-01-01T23:59:59.000Z

    Cosmic rays passing through large astrospheres can be efficiently cooled inside these "cavities" in the interstellar medium. Moreover, the energy spectra of these energetic particles are already modulated in front of the astrospherical bow shocks. We study the cosmic ray flux in and around lambda Cephei as an example for an astrosphere. The large-scale plasma flow is modeled hydrodynamically with radiative cooling. We studied the cosmic ray flux in a stellar wind cavity using a transport model based on stochastic differential equations. The required parameters, most importantly, the elements of the diffusion tensor, are based on the heliospheric parameters. The magnetic field required for the diffusion coefficients is calculated kinematically. We discuss the transport in an astrospheric scenario with varying parameters for the transport coefficients. We show that large stellar wind cavities can act as sinks for the galactic cosmic ray flux and thus can give rise to small-scale anisotropies in the direction to...

  3. Cosmic Rays and Gamma Ray Bursts From Microblazars

    E-Print Network [OSTI]

    Arnon Dar

    1998-09-13T23:59:59.000Z

    Highly relativistic jets from merger and accretion induced collapse of compact stellar objects, which may produce the cosmological gamma ray bursts (GRBs), are also very efficient and powerful cosmic ray accelerators. The expected luminosity, energy spectrum and chemical composition of cosmic rays from Galactic GRBs, most of which do not point in our direction, can explain the observed properties of Galactic cosmic rays.

  4. Gamma-Ray Bursts

    E-Print Network [OSTI]

    P. Meszaros

    2006-05-30T23:59:59.000Z

    Gamma-ray bursts are the most luminous explosions in the Universe, and their origin and mechanism are the focus of intense research and debate. More than three decades after their discovery, and after pioneering breakthroughs from space and ground experiments, their study is entering a new phase with the recently launched Swift satellite. The interplay between these observations and theoretical models of the prompt gamma ray burst and its afterglow is reviewed.

  5. Gamma ray camera

    DOE Patents [OSTI]

    Perez-Mendez, Victor (Berkeley, CA)

    1997-01-01T23:59:59.000Z

    A gamma ray camera for detecting rays emanating from a radiation source such as an isotope. The gamma ray camera includes a sensor array formed of a visible light crystal for converting incident gamma rays to a plurality of corresponding visible light photons, and a photosensor array responsive to the visible light photons in order to form an electronic image of the radiation therefrom. The photosensor array is adapted to record an integrated amount of charge proportional to the incident gamma rays closest to it, and includes a transparent metallic layer, photodiode consisting of a p-i-n structure formed on one side of the transparent metallic layer, and comprising an upper p-type layer, an intermediate layer and a lower n-type layer. In the preferred mode, the scintillator crystal is composed essentially of a cesium iodide (CsI) crystal preferably doped with a predetermined amount impurity, and the p-type upper intermediate layers and said n-type layer are essentially composed of hydrogenated amorphous silicon (a-Si:H). The gamma ray camera further includes a collimator interposed between the radiation source and the sensor array, and a readout circuit formed on one side of the photosensor array.

  6. Gamma ray camera

    DOE Patents [OSTI]

    Perez-Mendez, V.

    1997-01-21T23:59:59.000Z

    A gamma ray camera is disclosed for detecting rays emanating from a radiation source such as an isotope. The gamma ray camera includes a sensor array formed of a visible light crystal for converting incident gamma rays to a plurality of corresponding visible light photons, and a photosensor array responsive to the visible light photons in order to form an electronic image of the radiation therefrom. The photosensor array is adapted to record an integrated amount of charge proportional to the incident gamma rays closest to it, and includes a transparent metallic layer, photodiode consisting of a p-i-n structure formed on one side of the transparent metallic layer, and comprising an upper p-type layer, an intermediate layer and a lower n-type layer. In the preferred mode, the scintillator crystal is composed essentially of a cesium iodide (CsI) crystal preferably doped with a predetermined amount impurity, and the p-type upper intermediate layers and said n-type layer are essentially composed of hydrogenated amorphous silicon (a-Si:H). The gamma ray camera further includes a collimator interposed between the radiation source and the sensor array, and a readout circuit formed on one side of the photosensor array. 6 figs.

  7. X-ray beam finder

    DOE Patents [OSTI]

    Gilbert, H.W.

    1983-06-16T23:59:59.000Z

    An X-ray beam finder for locating a focal spot of an X-ray tube includes a mass of X-ray opaque material having first and second axially-aligned, parallel-opposed faces connected by a plurality of substantially identical parallel holes perpendicular to the faces and a film holder for holding X-ray sensitive film tightly against one face while the other face is placed in contact with the window of an X-ray head.

  8. Gamma ray bursts in their historic context

    E-Print Network [OSTI]

    Trimble, V

    2004-01-01T23:59:59.000Z

    Gamma Ray Bursts In Their Historic Context Virginia TrimbleMD 20742 USA Abstract. Gamma ray bursts remained essentiallyalso applies to the gamma ray bursts. First, an observation

  9. Fluctuation X-Ray Scattering

    SciTech Connect (OSTI)

    Saldin, PI: D. K.; Co-I's: J. C. H. Spence and P. Fromme

    2013-01-25T23:59:59.000Z

    The work supported by the grant was aimed at developing novel methods of finding the structures of biomolecules using x-rays from novel sources such as the x-ray free electron laser and modern synchrotrons

  10. X-ray afterglows from gamma-ray bursts

    E-Print Network [OSTI]

    M. Tavani

    1997-03-24T23:59:59.000Z

    We consider possible interpretations of the recently detected X- ray afterglow from the gamma-ray burst source GRB 970228. Cosmological and Galactic models of gamma-ray bursts predict different flux and spectral evolution of X-ray afterglows. We show that models based on adiabatic expansion of relativistic forward shocks require very efficient particle energization or post-burst re-acceleration during the expansion. Cooling neutron star models predict a very distinctive spectral and flux evolution that can be tested in current X-ray data.

  11. Tunable X-ray source

    DOE Patents [OSTI]

    Boyce, James R. (Williamsburg, VA)

    2011-02-08T23:59:59.000Z

    A method for the production of X-ray bunches tunable in both time and energy level by generating multiple photon, X-ray, beams through the use of Thomson scattering. The method of the present invention simultaneously produces two X-ray pulses that are tunable in energy and/or time.

  12. X-ray lithography source

    DOE Patents [OSTI]

    Piestrup, M.A.; Boyers, D.G.; Pincus, C.

    1991-12-31T23:59:59.000Z

    A high-intensity, inexpensive X-ray source for X-ray lithography for the production of integrated circuits is disclosed. Foil stacks are bombarded with a high-energy electron beam of 25 to 250 MeV to produce a flux of soft X-rays of 500 eV to 3 keV. Methods of increasing the total X-ray power and making the cross section of the X-ray beam uniform are described. Methods of obtaining the desired X-ray-beam field size, optimum frequency spectrum and eliminating the neutron flux are all described. A method of obtaining a plurality of station operation is also described which makes the process more efficient and economical. The satisfying of these issues makes transition radiation an excellent moderate-priced X-ray source for lithography. 26 figures.

  13. X-ray lithography source

    DOE Patents [OSTI]

    Piestrup, Melvin A. (Woodside, CA); Boyers, David G. (Mountain View, CA); Pincus, Cary (Sunnyvale, CA)

    1991-01-01T23:59:59.000Z

    A high-intensity, inexpensive X-ray source for X-ray lithography for the production of integrated circuits. Foil stacks are bombarded with a high-energy electron beam of 25 to 250 MeV to produce a flux of soft X-rays of 500 eV to 3 keV. Methods of increasing the total X-ray power and making the cross section of the X-ray beam uniform are described. Methods of obtaining the desired X-ray-beam field size, optimum frequency spectrum and elminating the neutron flux are all described. A method of obtaining a plurality of station operation is also described which makes the process more efficient and economical. The satisfying of these issues makes transition radiation an exellent moderate-priced X-ray source for lithography.

  14. Unidentified Gamma-Ray Sources: Hunting Gamma-Ray Blazars

    SciTech Connect (OSTI)

    Massaro, F.; D'Abrusco, R.; Tosti, G.; Ajello, M.; Gasparrini, A.Paggi.D.

    2012-04-02T23:59:59.000Z

    One of the main scientific objectives of the ongoing Fermi mission is unveiling the nature of the unidentified {gamma}-ray sources (UGSs). Despite the large improvements of Fermi in the localization of {gamma}-ray sources with respect to the past {gamma}-ray missions, about one third of the Fermi-detected objects are still not associated to low energy counterparts. Recently, using the Wide-field Infrared Survey Explorer (WISE) survey, we discovered that blazars, the rarest class of Active Galactic Nuclei and the largest population of {gamma}-ray sources, can be recognized and separated from other extragalactic sources on the basis of their infrared (IR) colors. Based on this result, we designed an association method for the {gamma}-ray sources to recognize if there is a blazar candidate within the positional uncertainty region of a generic {gamma}-ray source. With this new IR diagnostic tool, we searched for {gamma}-ray blazar candidates associated to the UGS sample of the second Fermi {gamma}-ray catalog (2FGL). We found that our method associates at least one {gamma}-ray blazar candidate as a counterpart each of 156 out of 313 UGSs analyzed. These new low-energy candidates have the same IR properties as the blazars associated to {gamma}-ray sources in the 2FGL catalog.

  15. The HAWC Gamma-Ray Observatory: Observations of Cosmic Rays

    E-Print Network [OSTI]

    Abeysekara, A U; Alvarez, C; lvarez, J D; Arceo, R; Arteaga-Velzquez, J C; Solares, H A Ayala; Barber, A S; Baughman, B M; Bautista-Elivar, N; Belmont, E; BenZvi, S Y; Berley, D; Rosales, M Bonilla; Braun, J; Caballero-Lopez, R A; Caballero-Mora, K S; Carramiana, A; Castillo, M; Cotti, U; Cotzomi, J; de la Fuente, E; De Len, C; DeYoung, T; Hernandez, R Diaz; Daz-Vlez, J C; Dingus, B L; DuVernois, M A; Ellsworth, R W; Fernandez, A; Fiorino, D W; Fraija, N; Galindo, A; Garfias, F; Gonzlez, L X; Gonzlez, M M; Goodman, J A; Grabski, V; Gussert, M; Hampel-Arias, Z; Hui, C M; Hntemeyer, P; Imran, A; Iriarte, A; Karn, P; Kieda, D; Kunde, G J; Lara, A; Lauer, R J; Lee, W H; Lennarz, D; Vargas, H Len; Linares, E C; Linnemann, J T; Longo, M; Luna-GarcIa, R; Marinelli, A; Martinez, H; Martinez, O; Martnez-Castro, J; Matthews, J A J; Miranda-Romagnoli, P; Moreno, E; Mostaf, M; Nava, J; Nellen, L; Newbold, M; Noriega-Papaqui, R; Oceguera-Becerra, T; Patricelli, B; Pelayo, R; Prez-Prez, E G; Pretz, J; Rivire, C; Rosa-Gonzlez, D; Salazar, H; Salesa, F; Sanchez, F E; Sandoval, A; Santos, E; Schneider, M; Silich, S; Sinnis, G; Smith, A J; Sparks, K; Springer, R W; Taboada, I; Toale, P A; Tollefson, K; Torres, I; Ukwatta, T N; Villaseor, L; Weisgarber, T; Westerhoff, S; Wisher, I G; Wood, J; Yodh, G B; Younk, P W; Zaborov, D; Zepeda, A; Zhou, H

    2013-01-01T23:59:59.000Z

    We describe measurements of GeV and TeV cosmic rays with the High-Altitude Water Cherenkov Gamma-Ray Observatory, or HAWC. The measurements include the observation of the shadow of the moon; the observation of small-scale and large-scale angular clustering of the TeV cosmic rays; the prospects for measurement of transient solar events with HAWC; and the observation of Forbush decreases with the HAWC engineering array and HAWC-30.

  16. X-Ray Diagnostics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered energy consumption byAbout SRNL Home SRNL main campusMore than 20X-Ray Diagnostics

  17. Ray2008.ppt

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared at 278, 298, andEpidermal Growth Factor.Tariff Rates FYRay Ray ,

  18. High energy cosmic rays, gamma rays and neutrinos from AGN

    E-Print Network [OSTI]

    Yukio Tomozawa

    2008-02-03T23:59:59.000Z

    The author reviews a model for the emission of high energy cosmic rays, gamma-rays and neutrinos from AGN (Active Galactic Nuclei) that he has proposed since 1985. Further discussion of the knee energy phenomenon of the cosmic ray energy spectrum requires the existence of a heavy particle with mass in the knee energy range. A possible method of detecting such a particle in the Pierre Auger Project is suggested. Also presented is a relation between the spectra of neutrinos and gamma-rays emitted from AGN. This relation can be tested by high energy neutrino detectors such as ICECUBE, the Mediterranean Sea Detector and possibly by the Pierre Auger Project.

  19. X-ray Flares in Gamma-Ray Bursts.

    E-Print Network [OSTI]

    Morris, David

    2008-01-01T23:59:59.000Z

    ??Data from the Swift mission have now shown that flares are a common component of Gamma-Ray Burst afterglows, appearing in roughly 50% of GRBs to (more)

  20. Miniature x-ray source

    DOE Patents [OSTI]

    Trebes, James E. (Livermore, CA); Stone, Gary F. (Livermore, CA); Bell, Perry M. (Tracy, CA); Robinson, Ronald B. (Modesto, CA); Chornenky, Victor I. (Minnetonka, MN)

    2002-01-01T23:59:59.000Z

    A miniature x-ray source capable of producing broad spectrum x-ray emission over a wide range of x-ray energies. The miniature x-ray source comprises a compact vacuum tube assembly containing a cathode, an anode, a high voltage feedthru for delivering high voltage to the anode, a getter for maintaining high vacuum, a connection for an initial vacuum pump down and crimp-off, and a high voltage connection for attaching a compact high voltage cable to the high voltage feedthru. At least a portion of the vacuum tube wall is highly x-ray transparent and made, for example, from boron nitride. The compact size and potential for remote operation allows the x-ray source, for example, to be placed adjacent to a material sample undergoing analysis or in proximity to the region to be treated for medical applications.

  1. Gamma Ray Burst Afterglow Observations.

    E-Print Network [OSTI]

    Updike, Adria

    2007-01-01T23:59:59.000Z

    ??Gamma ray bursts (GRBs) are among the most luminous explosions in the universe. We present an overview of the observational history of GRBs and the (more)

  2. Gamma-ray burst populations.

    E-Print Network [OSTI]

    Virgili, Francisco J.

    2011-01-01T23:59:59.000Z

    ??Over the last fifty years the field of gamma-ray bursts has shown incredible growth, but the amassing of data has also left observers and theorists (more)

  3. X-ray fluorescence mapping

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    biololgical cells, over the measurement of impurities in solar cells, to the rare earth content of geological materials. A somewhat 'typical' layout for a X-ray fluorescence...

  4. Light Curves of Swift Gamma Ray Bursts

    E-Print Network [OSTI]

    Paolo Cea

    2006-09-22T23:59:59.000Z

    Recent observations from the Swift gamma-ray burst mission indicate that a fraction of gamma ray bursts are characterized by a canonical behaviour of the X-ray afterglows. We present an effective theory which allows us to account for X-ray light curves of both (short - long) gamma ray bursts and X-ray rich flashes. We propose that gamma ray bursts originate from massive magnetic powered pulsars.

  5. A meeting is planned Tuesday

    E-Print Network [OSTI]

    Thermonuclear Experimental Reactor (ITER) -- a test bed for what is being billed as a safe and inexhaustible | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Google It: International Thermonuclear Spokesman Fabio Fabbi Questions Eu Optimism Experimental Reactor

  6. CMRR SEIS commments Tuesday Final

    National Nuclear Security Administration (NNSA)

    estimated: * Waste generation may double, triple, or even quadruple, which violates DOE pollution prevention policies; * Air emissions are expected to increase several fold; and...

  7. Ultrahigh Energy Cosmic Rays and Prompt TeV Gamma Rays from Gamma Ray Bursts

    E-Print Network [OSTI]

    Pijushpani Bhattacharjee; Nayantara Gupta

    2003-05-12T23:59:59.000Z

    Gamma Ray Bursts (GRBs) have been proposed as one {\\it possible} class of sources of the Ultrahigh Energy Cosmic Ray (UHECR) events observed up to energies $\\gsim10^{20}\\ev$. The synchrotron radiation of the highest energy protons accelerated within the GRB source should produce gamma rays up to TeV energies. Here we briefly discuss the implications on the energetics of the GRB from the point of view of the detectability of the prompt TeV gamma rays of proton-synchrotron origin in GRBs in the up-coming ICECUBE muon detector in the south pole.

  8. Cosmic Rays and Experiment CZELTA

    SciTech Connect (OSTI)

    Smolek, Karel; Nyklicek, Michal [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, 128 00 Prague 2 (Czech Republic); Kovacikova, Petra [Faculty of Philosophy and Science, Silesian University in Opava, Bezrucovo namesti 13, 746 01 Opava (Czech Republic)

    2007-11-26T23:59:59.000Z

    This paper gives a review of the physics of cosmic rays with emphasis on the methods of detection and study. A summary is given of the Czech project CZELTA which is part of a multinational program to study cosmic rays with energies above 10{sup 14} eV.

  9. The Origin of Cosmic Rays

    ScienceCinema (OSTI)

    Pasquale Blasi

    2010-01-08T23:59:59.000Z

    Cosmic Rays reach the Earth from space with energies of up to more than 1020 eV, carrying information on the most powerful particle accelerators that Nature has been able to assemble. Understanding where and how cosmic rays originate has required almost one century of investigations, and, although the last word is not written yet, recent observations and theory seem now to fit together to provide us with a global picture of the origin of cosmic rays of unprecedented clarity. Here we will describe what we learned from recent observations of astrophysical sources (such as supernova remnants and active galaxies) and we will illustrate what these observations tell us about the physics of particle acceleration and transport. We will also discuss the ?end? of the Galactic cosmic ray spectrum, which bridges out attention towards the so called ultra high energy cosmic rays (UHECRs). At ~1020 eV the gyration scale of cosmic rays in cosmic magnetic fields becomes large enough to allow us to point back to their sources, thereby allowing us to perform ?cosmic ray astronomy?, as confirmed by the recent results obtained with the Pierre Auger Observatory. We will discuss the implications of these observations for the understanding of UHECRs, as well as some questions which will likely remain unanswered and will be the target of the next generation of cosmic ray experiments.

  10. On the broken ray transform

    E-Print Network [OSTI]

    Joonas Ilmavirta

    2014-09-26T23:59:59.000Z

    This PhD thesis studies the broken ray transform, a generalization of the geodesic X-ray transform where geodesics are replaced with broken rays that reflect on a part of the boundary. The fundamental question is whether this transform is injective. We employ four different methods to approach this question, and each of them gives interesting results. Direct calculation can be used in a ball, where the geometry is particularly simple. If the reflecting part of the boundary is (piecewise) flat, a reflection argument can be used to reduce the problem to the usual X-ray transform. In some geometries one can use broken rays near the boundary to determine the values of the unknown function at the reflector, and even construct its Taylor series. One can also use energy estimates -- which in this context are known as Pestov identities -- to show injectivity in the presence of one convex reflecting obstacle. Many of these methods work also on Riemannian manifolds. We also discuss the periodic broken ray transform, where the integrals are taken over periodic broken rays. The broken ray transform and its periodic version have applications in other inverse problems, including Calder\\'on's problem and problems related to spectral geometry. A more detailed abstract can be found in the PDF file. This version only contains the introductory parts of the thesis. The full thesis also contains five articles.

  11. X-ray shearing interferometer

    DOE Patents [OSTI]

    Koch, Jeffrey A. (Livermore, CA)

    2003-07-08T23:59:59.000Z

    An x-ray interferometer for analyzing high density plasmas and optically opaque materials includes a point-like x-ray source for providing a broadband x-ray source. The x-rays are directed through a target material and then are reflected by a high-quality ellipsoidally-bent imaging crystal to a diffraction grating disposed at 1.times. magnification. A spherically-bent imaging crystal is employed when the x-rays that are incident on the crystal surface are normal to that surface. The diffraction grating produces multiple beams which interfere with one another to produce an interference pattern which contains information about the target. A detector is disposed at the position of the image of the target produced by the interfering beams.

  12. X-ray Stacking 2008-Apr-22 Astrostats X-ray Stacking

    E-Print Network [OSTI]

    Wolfe, Patrick J.

    X-ray Stacking 2008-Apr-22 Astrostats X-ray Stacking Tom Aldcroft SAO/CXC #12;X-ray Stacking 2008 analysis for a sample Stacking ­ mean properties of sample Chandra X-ray data (faint point sources) are photon-limited with low background => stacking in X-rays is very effective #12;X-ray Stacking 2008-Apr-22

  13. Studying Gamma Ray Bursts from a

    E-Print Network [OSTI]

    ?umer, Slobodan

    Studying Gamma Ray Bursts from a new perspective! {... Unraveling some mysteries and adding new Radio Op0cal X-ray Short ( energy -ray photons... ... accompained by a considerable long las0ng emission

  14. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Lensless X-Ray Imaging in Reflection Lensless X-Ray Imaging in Reflection Print Wednesday, 26 October 2011 00:00 The advent of x-ray free-electron laser (XFEL) light sources has...

  15. Fiber fed x-ray/gamma ray imaging apparatus

    DOE Patents [OSTI]

    Hailey, C.J.; Ziock, K.P.

    1992-06-02T23:59:59.000Z

    X-ray/gamma ray imaging apparatus is disclosed for detecting the position, energy, and intensity of x-ray/gamma ray radiation comprising scintillation means disposed in the path of such radiation and capable of generating photons in response to such radiation; first photodetection means optically bonded to the scintillation means and capable of generating an electrical signal indicative of the intensity, and energy of the radiation detected by the scintillation means; second photodetection means capable of generating an electrical signal indicative of the position of the radiation in the radiation pattern; and means for optically coupling the scintillation means to the second photodetection means. The photodetection means are electrically connected to control and storage means which may also be used to screen out noise by rejecting a signal from one photodetection means not synchronized to a signal from the other photodetection means; and also to screen out signals from scattered radiation. 6 figs.

  16. Fiber fed x-ray/gamma ray imaging apparatus

    DOE Patents [OSTI]

    Hailey, Charles J. (San Francisco, CA); Ziock, Klaus-Peter (Livermore, CA)

    1992-01-01T23:59:59.000Z

    X-ray/gamma ray imaging apparatus is disclosed for detecting the position, energy, and intensity of x-ray/gamma ray radiation comprising scintillation means disposed in the path of such radiation and capable of generating photons in response to such radiation; first photodetection means optically bonded to the scintillation means and capable of generating an electrical signal indicative of the intensity, and energy of the radiation detected by the scintillation means; second photodetection means capable of generating an electrical signal indicative of the position of the radiation in the radiation pattern; and means for optically coupling the scintillation means to the second photodetection means. The photodetection means are electrically connected to control and storage means which may also be used to screen out noise by rejecting a signal from one photodetection means not synchronized to a signal from the other photodetection means; and also to screen out signals from scattered radiation.

  17. Ultrahigh Energy Cosmic Rays Detection

    E-Print Network [OSTI]

    Carla Aramo

    2005-09-06T23:59:59.000Z

    The paper describes methods used for the detection of cosmic rays with energies above 10^18 eV (UHECR, UltraHigh Energy Cosmic Rays). It had been anticipated there would be a cutoff in the energy spectrum of primary cosmic rays around 3 10^19 eV induced by their interaction with the 2.7 K primordial photons. This has become known as the GZK cutoff. However, several showers have been detected with estimated primary energy exceeding this limit.

  18. X-ray Spectral Properties of Gamma-Ray Bursts

    E-Print Network [OSTI]

    T. E. Strohmayer; E. E. Fenimore; T. Murakami; A. Yoshida

    1997-12-18T23:59:59.000Z

    We summarize the spectral characteristics of a sample of 22 bright gamma-ray bursts detected with the gamma-ray burst sensors aboard the satellite Ginga. This instrument employed a proportional and scintillation counter to provide sensitivity to photons in the 2 - 400 keV range, providing a unique opportunity to characterize the largely unexplored X-ray properties of gamma-ray bursts. The photon spectra of the Ginga bursts are well described by a low energy slope, a bend energy, and a high energy slope. In the energy range where they can be compared, this result is consistent with burst spectral analyses obtained from the BATSE experiment aboard the Compton Observatory. However, below 20 keV we find evidence for a positive spectral number index in approximately 40% of our burst sample, with some evidence for a strong rolloff at lower energies in a few events. There is a correlation (Pearson's r = -0.62) between the low energy slope and the bend energy. We find that the distribution of spectral bend energies extends below 10 keV. The observed ratio of energy emitted in the X-rays relative to the gamma-rays can be much larger than a few percent and, in fact, is sometimes larger than unity. The average for our sample is 24%.

  19. Miniature x-ray source

    DOE Patents [OSTI]

    Trebes, James E. (Livermore, CA); Bell, Perry M. (Tracy, CA); Robinson, Ronald B. (Modesto, CA)

    2000-01-01T23:59:59.000Z

    A miniature x-ray source utilizing a hot filament cathode. The source has a millimeter scale size and is capable of producing broad spectrum x-ray emission over a wide range of x-ray energies. The miniature source consists of a compact vacuum tube assembly containing the hot filament cathode, an anode, a high voltage feedthru for delivering high voltage to the cathode, a getter for maintaining high vacuum, a connector for initial vacuum pump down and crimp-off, and a high voltage connection for attaching a compact high voltage cable to the high voltage feedthru. At least a portion of the vacuum tube wall is fabricated from highly x-ray transparent materials, such as sapphire, diamond, or boron nitride.

  20. Modeling gamma-ray bursts.

    E-Print Network [OSTI]

    Maxham, Amanda

    2011-01-01T23:59:59.000Z

    ??Discovered serendipitously in the late 1960s, gamma-ray bursts (GRBs) are huge explosions of energy that happen at cosmological distances. They provide a grand physical playground (more)

  1. Gamma-Ray Burst Lines

    E-Print Network [OSTI]

    Michael S. Briggs

    1999-10-20T23:59:59.000Z

    The evidence for spectral features in gamma-ray bursts is summarized. As a guide for evaluating the evidence, the properties of gamma-ray detectors and the methods of analyzing gamma-ray spectra are reviewed. In the 1980's, observations indicated that absorption features below 100 keV were present in a large fraction of bright gamma-ray bursts. There were also reports of emission features around 400 keV. During the 1990's the situation has become much less clear. A small fraction of bursts observed with BATSE have statistically significant low-energy features, but the reality of the features is suspect because in several cases the data of the BATSE detectors appear to be inconsistent. Furthermore, most of the possible features appear in emission rather than the expected absorption. Analysis of data from other instruments has either not been finalized or has not detected lines.

  2. Cosmic Rays and Global Warming

    E-Print Network [OSTI]

    T. Sloan; A W Wolfendale

    2007-06-28T23:59:59.000Z

    It has been claimed by others that observed temporal correlations of terrestrial cloud cover with `the cosmic ray intensity' are causal. The possibility arises, therefore, of a connection between cosmic rays and Global Warming. If true, the implications would be very great. We have examined this claim to look for evidence to corroborate it. So far we have not found any and so our tentative conclusions are to doubt it. Such correlations as appear are more likely to be due to the small variations in solar irradiance, which, of course, correlate with cosmic rays. We estimate that less than 15% of the 11-year cycle warming variations are due to cosmic rays and less than 2% of the warming over the last 35 years is due to this cause.

  3. Gamma Ray Bursts and CETI

    E-Print Network [OSTI]

    Frank D. Smith Jr

    1993-02-10T23:59:59.000Z

    Gamma ray burst sources are isotropically distributed. They could be located at distances $\\sim 1000$ AU. (Katz \\cite{JK92}) GRB signals have many narrow peaks that are unresolved at the millisecond time resolution of existing observations. \\cite{JK87} CETI could use stars as gravitational lenses for interstellar gamma ray laser beam communication. Much better time resolution of GRB signals could rule out (or confirm?) the speculative hypothesis that GRB = CETI.

  4. Multigamma-ray calibration sources

    SciTech Connect (OSTI)

    Meyer, R.A.; Massey, T.N.

    1983-05-01T23:59:59.000Z

    We have calibrated a self-consistent set of multigamma-ray standards using the automated multi-spectrometry ..gamma..-ray counting facility at LLNL's Nuclear Chemistry Division. Pure sources of long-lived activity were produced by mass separation and/or chemical purification. The sources were counted individually and in combination on several different calibrated spectrometer systems. These systems utilize various detectors ranging from small (x-ray) detectors to large volume high-purity Ge detectors. This has allowed the use of the most ideal individual detector-efficiency characteristics for the determination of the relative ..gamma..-ray intensities. Precise energy measurements, reported earlier (Meyer, 1976) have been performed by an independent method. Both the energy and ..gamma..-ray-emission probabilities determined compare well with independently established values such as the recent ICRM intercomparison of /sup 152/Eu. We discuss our investigations aimed at resolving the shape of the efficiency response function up to 10 MeV for large volume Ge(Li) and high-purity Ge detectors. Recent results on the ..gamma..-ray-emission probabilities per decay for /sup 149/Gd and /sup 168/Tm multigamma-ray sources are discussed. For /sup 168/Tm, we deduce a 0.01% ..beta../sup -/ branch to the 87.73-keV level in /sup 168/Yb rather than the previous value which was a factor of 200 greater. In addition, we describe current cooperative efforts aimed at establishing a consistent set of data for short-lived fission products. Included are recent measurements on the bromine fission products with ..gamma.. rays up to 7 MeV.

  5. Neutrinos from Gamma Ray Bursts

    E-Print Network [OSTI]

    Karl Mannheim

    2000-10-18T23:59:59.000Z

    The observed fluxes of cosmic rays and gamma rays are used to infer the maximum allowed high-energy neutrino flux allowed for Gamma Ray Bursts (GRBs), following Mannheim, Protheroe, and Rachen (2000). It is shown that if GRBs produce the ultrahigh-energy cosmic rays, they should contribute (a) at least 10% of the extragalactic gamma ray background between 3 MeV and 30 GeV, contrary to their observed energy flux which is only a minute fraction of this flux, and (b) a cumulative neutrino flux a factor of 20 below the AMANDA (Neutrino 2000) limit on isotropic neutrinos. This could have two implications, either GRBs do not produce the ultrahigh energy cosmic rays or that the GRBs are strongly beamed and emit most of their power at energies well above 100 GeV implausibly increasing the energy requirements, but consistent with the marginal detections of a few low-redshift GRBs by MILAGRITO, HEGRA-AIROBICC, and the Tibet-Array. All crucial measurements to test the models will be available in the next few years. These are measurements of (i) high-energy neutrinos with AMANDA-ICECUBE or an enlarged ANTARES/NESTOR ocean detector, (ii) GRB redshifts from HETE-2 follow-up studies, and (iii) GRB spectra above 10 GeV with low-threshold imaging air Cherenkov telescopes such as MAGIC and the space telescopes AGILE and GLAST.

  6. Gamma-Ray Bursts, Ultra High Energy Cosmic Rays, and Cosmic Gamma-Ray Background

    E-Print Network [OSTI]

    Tomonori Totani

    1999-04-13T23:59:59.000Z

    We argue that gamma-ray bursts (GRBs) may be the origin of the cosmic gamma-ray background radiation observed in GeV range. It has theoretically been discussed that protons may carry a much larger amount of energy than electrons in GRBs, and this large energy can be radiated in TeV range by synchrotron radiation of ultra-high-energy protons (\\sim 10^{20} eV). The possible detection of GRBs above 10 TeV suggested by the Tibet and HEGRA groups also supports this idea. If this is the case, most of TeV gamma-rays from GRBs are absorbed in intergalactic fields and eventually form GeV gamma-ray background, whose flux is in good agreement with the recent observation.

  7. Aneta Siemiginowska Chandra X-ray Center

    E-Print Network [OSTI]

    Wolfe, Patrick J.

    -ray and gamma-ray · High Energy Sky · Chandra X-ray Observatory · examples of typical X-ray data, · an example of a data analysis process · statistical challenges · what do we learn from the data? #12;What is Astronomy and phenomena do we study and how? Solar System: Sun and sollar wind, planets, moons, asteroids, comets Our

  8. Gamma ray bursts ROBERT S MACKAY

    E-Print Network [OSTI]

    Rourke, Colin

    Gamma ray bursts ROBERT S MACKAY COLIN ROURKE We propose that a gamma ray burst is a kinematic Gamma ray bursts are intense flashes of electromagnetic radiation of cosmic origin lasting from ten accepted mechanism. We propose that a gamma ray burst is simply a kinematic effect, namely the effect

  9. X-ray Emission from Massive Stars

    E-Print Network [OSTI]

    Cohen, David

    X-ray Emission from Massive Stars David Cohen Department of Physics and Astronomy Swarthmore be related to the production of X-rays on massive stars. If so, massive stars' X-rays are much different than those found our own Sun and other cooler stars like the Sun that produce X-rays via magnetic activity

  10. X-ray Emission from Massive Stars

    E-Print Network [OSTI]

    Cohen, David

    X-ray Emission from Massive Stars David Cohen Department of Physics and Astronomy Swarthmore #12;What is the mechanism by which massive stars produce x-rays? New results from the Chandra X-ray Observatory ­ high-resolution x-ray spectroscopy: measuring Doppler broadening in emission lines Testing

  11. Ultrafast X-ray Absorption Spectroscopy using Laser-Driven Electron X-ray Sources (LEXS)

    E-Print Network [OSTI]

    Guo, Ting

    : ultrafast x-rays, x-ray absorption spectroscopy, terawatt lasers, ultrafast reaction dynamics, atomic motion atomic motion by scrutinizing the changes in x- ray absorption spectra during reactions. FirstUltrafast X-ray Absorption Spectroscopy using Laser-Driven Electron X-ray Sources (LEXS) Guangjun

  12. Gamma-RayGamma-Ray Bursts: from SwiftBursts: from Swift

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Gamma-RayGamma-Ray Bursts: from SwiftBursts: from Swift to GLASTto GLAST Bing ZhangBing ZhangGehrels, et al), et al) #12;Gamma-ray bursts: the mostGamma-ray bursts: the most violent explosions fireball central photosphere internal external shocks engine (shocks) (reverse) (forward) gamma-ray UV

  13. Compact x-ray source and panel

    DOE Patents [OSTI]

    Sampayon, Stephen E. (Manteca, CA)

    2008-02-12T23:59:59.000Z

    A compact, self-contained x-ray source, and a compact x-ray source panel having a plurality of such x-ray sources arranged in a preferably broad-area pixelized array. Each x-ray source includes an electron source for producing an electron beam, an x-ray conversion target, and a multilayer insulator separating the electron source and the x-ray conversion target from each other. The multi-layer insulator preferably has a cylindrical configuration with a plurality of alternating insulator and conductor layers surrounding an acceleration channel leading from the electron source to the x-ray conversion target. A power source is connected to each x-ray source of the array to produce an accelerating gradient between the electron source and x-ray conversion target in any one or more of the x-ray sources independent of other x-ray sources in the array, so as to accelerate an electron beam towards the x-ray conversion target. The multilayer insulator enables relatively short separation distances between the electron source and the x-ray conversion target so that a thin panel is possible for compactness. This is due to the ability of the plurality of alternating insulator and conductor layers of the multilayer insulators to resist surface flashover when sufficiently high acceleration energies necessary for x-ray generation are supplied by the power source to the x-ray sources.

  14. Cosmic Rays and Global Warming

    SciTech Connect (OSTI)

    Sloan, T. [Physics Department, University of Lancaster, Lancaster, UK (United Kingdom); Wolfendale, A. W. [Physics Department, Durham University, Durham (United Kingdom)

    2008-01-24T23:59:59.000Z

    Some workers have claimed that the observed temporal correlations of (low level) terrestrial cloud cover with the cosmic ray intensity changes, due to solar modulation, are causal. The possibility arises, therefore, of a connection between cosmic rays and Global Warming. If true, the implications would be very great. We have examined this claim in some detail. So far, we have not found any evidence in support and so our conclusions are to doubt it. From the absence of corroborative evidence we estimate that less than 15% at the 95% confidence level, of the 11-year cycle warming variations are due to cosmic rays and less than 2% of the warming over the last 43 years is due to this cause. The origin of the correlation itself is probably the cycle of solar irradiance although there is, as yet, no certainty.

  15. Selected Results from Ground-Based Cosmic Ray and Gamma-Ray Experiments

    E-Print Network [OSTI]

    N. Magnussen

    1998-05-13T23:59:59.000Z

    Selected results from the HEGRA experiment on charged Cosmic Rays and on very high energy gamma-rays are presented. The MAGIC Telescope is presented as an outlook to the future of Gamma-Ray astronomy.

  16. Beta ray flux measuring device

    DOE Patents [OSTI]

    Impink, Jr., Albert J. (Murrysville, PA); Goldstein, Norman P. (Murrysville, PA)

    1990-01-01T23:59:59.000Z

    A beta ray flux measuring device in an activated member in-core instrumentation system for pressurized water reactors. The device includes collector rings positioned about an axis in the reactor's pressure boundary. Activated members such as hydroballs are positioned within respective ones of the collector rings. A response characteristic such as the current from or charge on a collector ring indicates the beta ray flux from the corresponding hydroball and is therefore a measure of the relative nuclear power level in the region of the reactor core corresponding to the specific exposed hydroball within the collector ring.

  17. Neutrinos from Gamma Ray Bursts

    E-Print Network [OSTI]

    F. Halzen; G. Jaczko

    1996-02-07T23:59:59.000Z

    We show that the detection of neutrinos from a typical gamma ray burst requires a kilometer-scale detector. We argue that large bursts should be visible with the neutrino telescopes under construction. We emphasize the 3 techniques by which neutrino telescopes can perform this search: by triggering on i) bursts of muons from muon neutrinos, ii) muons from air cascades initiated by high energy gamma rays and iii) showers made by relatively low energy ($\\simeq 100\\,\\mev$) electron neutrinos. Timing of neutrino-photon coincidences may yield a measurement of the neutrino mass to order $10^{-5}$~eV, an interesting range in light of the solar neutrino anomaly.

  18. Gamma-ray Imaging Methods

    SciTech Connect (OSTI)

    Vetter, K; Mihailescu, L; Nelson, K; Valentine, J; Wright, D

    2006-10-05T23:59:59.000Z

    In this document we discuss specific implementations for gamma-ray imaging instruments including the principle of operation and describe systems which have been built and demonstrated as well as systems currently under development. There are several fundamentally different technologies each with specific operational requirements and performance trade offs. We provide an overview of the different gamma-ray imaging techniques and briefly discuss challenges and limitations associated with each modality (in the appendix we give detailed descriptions of specific implementations for many of these technologies). In Section 3 we summarize the performance and operational aspects in tabular form as an aid for comparing technologies and mapping technologies to potential applications.

  19. Focused X-ray source

    DOE Patents [OSTI]

    Piestrup, M.A.; Boyers, D.G.; Pincus, C.I.; Maccagno, P.

    1990-08-21T23:59:59.000Z

    Disclosed is an intense, relatively inexpensive X-ray source (as compared to a synchrotron emitter) for technological, scientific, and spectroscopic purposes. A conical radiation pattern produced by a single foil or stack of foils is focused by optics to increase the intensity of the radiation at a distance from the conical radiator. 8 figs.

  20. Spectral analysis of X-ray binaries

    E-Print Network [OSTI]

    Fridriksson, Joel Karl

    2011-01-01T23:59:59.000Z

    In this thesis, I present work from three separate research projects associated with observations of X-ray binaries. Two of those revolve around spectral characteristics of neutron star low-mass X-ray binaries (NS-LMXBs), ...

  1. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    X-Ray Imaging in Reflection Print The advent of x-ray free-electron laser (XFEL) light sources has led to an outburst of research activities in the field of lensless imaging. XFELs...

  2. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    X-Ray Imaging in Reflection Print Wednesday, 26 October 2011 00:00 The advent of x-ray free-electron laser (XFEL) light sources has led to an outburst of research activities...

  3. Producing X-rays at the APS

    ScienceCinema (OSTI)

    None

    2013-04-19T23:59:59.000Z

    An introduction and overview of the Advanced Photon Source at Argonne National Laboratory, the technology that produces the brightest X-ray beams in the Western Hemisphere, and the research carried out by scientists using those X-rays.

  4. Imaging the High Energy Cosmic Ray Sky

    E-Print Network [OSTI]

    Haviland, David

    Imaging the High Energy Cosmic Ray Sky PETTER HOFVERBERG Licentiate Thesis Stockholm, Sweden 2006 #12;#12;Licentiate Thesis Imaging the High Energy Cosmic Ray Sky Petter Hofverberg Particle

  5. Terrestrial Effects of High Energy Cosmic Rays

    E-Print Network [OSTI]

    Atri, Dimitra

    2011-04-26T23:59:59.000Z

    On geological timescales, the Earth is likely to be exposed to higher than the usual flux of high energy cosmic rays (HECRs) from astrophysical sources such as nearby supernovae, gamma ray bursts or by galactic shocks. ...

  6. Phase-sensitive X-ray imager

    DOE Patents [OSTI]

    Baker, Kevin Louis

    2013-01-08T23:59:59.000Z

    X-ray phase sensitive wave-front sensor techniques are detailed that are capable of measuring the entire two-dimensional x-ray electric field, both the amplitude and phase, with a single measurement. These Hartmann sensing and 2-D Shear interferometry wave-front sensors do not require a temporally coherent source and are therefore compatible with x-ray tubes and also with laser-produced or x-pinch x-ray sources.

  7. Pulsed Gamma-Ray-Burst Afterglows

    E-Print Network [OSTI]

    J. Middleditch

    2009-01-01T23:59:59.000Z

    provides a candidate for the central engine of the gamma-ray burst (GRB) mechanism, both long and short

  8. Synchronization of x-ray pulses to the pump laser in an ultrafast x-ray facility

    E-Print Network [OSTI]

    Corlett, J.N.; Barry, W.; Byrd, J.M.; Schoenlein, R.; Zholents, A.

    2002-01-01T23:59:59.000Z

    Accurate timing of ultrafast x-ray probe pulses emitted fromOF X-RAY PULSES TO THE PUMP LASER IN AN ULTRAFAST X-RAY

  9. Multifrequency Observations of Gamma-Ray Burst

    E-Print Network [OSTI]

    J. Greiner

    1995-10-04T23:59:59.000Z

    Neither a flaring nor a quiescent counterpart to a gamma-ray burst has yet been convincingly identified at any wavelength region. The present status of the search for counterparts of classical gamma-ray bursts is given. Particular emphasis is put on the search for flaring counterparts, i.e. emission during or shortly after the gamma-ray emission.

  10. Ray Tracing JELLO Brand Paul S. Heckbert

    E-Print Network [OSTI]

    Treuille, Adrien

    Ray Tracing JELL­O ® Brand Gelatin Paul S. Heckbert Dessert Foods Division Pixar San Rafael, CA ABSTRACT Ray tracing has established itself in recent years as the most general image synthesis algorithm for ray tracing Jell­O ® brand gelatin. We believe the method may have application to other brands

  11. Chandra X-ray Observatory Center

    E-Print Network [OSTI]

    Chandra X-ray Observatory Center Harvard-Smithsonian Center for Astrophysics 60 Garden St in hot gas about 250 million light years from Earth. (Credit: X-ray: NASA/CXC/SAO/E.Bulbul, et al-Newton has revealed a mysterious X-ray signal in the data. This signal is represented in the circled data

  12. X-Ray Absorption Spectroscopy of Metallobiomolecules

    E-Print Network [OSTI]

    Scott, Robert A.

    2/9/07 1 X-Ray Absorption Spectroscopy of Metallobiomolecules The Outskirts of Structural Biology 9, 07] This is a tutorial about the use of X-ray Absorption Spectroscopy (XAS) in biology, RG; Eisenberger, P; Kincaid, BM "X-ray Absorption Spectroscopy of Biological Molecules" Annu. Rev

  13. Chandra X-ray Observatory Center

    E-Print Network [OSTI]

    Chandra X-ray Observatory Center Harvard-Smithsonian Center for Astrophysics 60 Garden St million light years from Earth. (Credit: X-ray: NASA/CXC/Wesleyan Univ./R.Kilgard, et al; Optical: NASA with optical data from the Hubble Space Telescope (red, green, and blue). The X-ray data reveal hundreds

  14. Cryotomography x-ray microscopy state

    DOE Patents [OSTI]

    Le Gros, Mark (Berkeley, CA); Larabell, Carolyn A. (Berkeley, CA)

    2010-10-26T23:59:59.000Z

    An x-ray microscope stage enables alignment of a sample about a rotation axis to enable three dimensional tomographic imaging of the sample using an x-ray microscope. A heat exchanger assembly provides cooled gas to a sample during x-ray microscopic imaging.

  15. X-ray Spectroscopy of Cool Stars

    E-Print Network [OSTI]

    M. Guedel

    2006-09-11T23:59:59.000Z

    High-resolution X-ray spectroscopy has addressed not only various topics in coronal physics of stars, but has also uncovered important features relevant for our understanding of stellar evolution and the stellar environment. I summarize recent progress in coronal X-ray spectroscopy and in particular also discuss new results from studies of X-rays from pre-main sequence stars.

  16. X-Ray Physics Evan Berkowitz

    E-Print Network [OSTI]

    X-Ray Physics Evan Berkowitz Junior, MIT Department of Physics (Dated: October 25, 2006) We measure a variety of phenomena related to X-Ray absorption and production. We present data which conforms within, as are 22 Na electron-positron annhilation lines. The importance of understanding x-rays is demonstrated

  17. Chandra X-ray Observatory Center

    E-Print Network [OSTI]

    Chandra X-ray Observatory Center Harvard-Smithsonian Center for Astrophysics 60 Garden St 200 million light years from Earth. (Credit: X-ray: NASA/CXC/UAH/M.Sun et al; Optical: NASA, ESA, & the Hubble Heritage Team (STScI/AURA) Caption: This composite image from the Chandra X-ray Observatory (blue

  18. X-Ray Absorption Spectroscopy of Metallobiomolecules

    E-Print Network [OSTI]

    Scott, Robert A.

    9/6/09 1 X-Ray Absorption Spectroscopy of Metallobiomolecules The Outskirts of Structural Biology 6, 09] This is a tutorial about the use of X-ray Absorption Spectroscopy (XAS) in biology, RG; Eisenberger, P; Kincaid, BM "X-ray Absorption Spectroscopy of Biological Molecules" Annu. Rev

  19. Chandra X-ray Observatory Center

    E-Print Network [OSTI]

    Chandra X-ray Observatory Center Harvard-Smithsonian Center for Astrophysics 60 Garden St. Cambridge, MA 02138 USA http://chandra.harvard.edu Four Supernova Remnants: NASA's Chandra X-ray Observatory's Chandra X-ray Observatory, four newly processed images of supernova remnants dramatically illustrate

  20. X-ray spectroscopy of low-mass X-ray binaries

    E-Print Network [OSTI]

    Juett, Adrienne Marie, 1976-

    2004-01-01T23:59:59.000Z

    I present high-resolution X-ray grating spectroscopy of neutron stars in low-mass X-ray binaries (LMXBs) using instruments onboard the Chandra X-ray Observatory and the X-ray Multi-Mirror Mission (XMM-Newton). The first ...

  1. SEISMIC RAY THEORY Seismic Ray Theory presents the most comprehensive treatment of the seismic

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    #12;SEISMIC RAY THEORY Seismic Ray Theory presents the most comprehensive treatment of the seismic ray method available. This method plays an important role in seismology, seismic exploration, and the interpretation of seismic measurements. The book presents a consistent treatment of the seismic ray method, based

  2. Extending The Methodology Of X-ray Crystallography To Allow X-ray

    E-Print Network [OSTI]

    Miao, Jianwei "John"

    , the radiation damage. While the radiation damage problem can be mitigated somewhat by using cryogenic techniques resolution without serious radiation damage to the specimens. Although X-ray crystallography becomesExtending The Methodology Of X-ray Crystallography To Allow X-ray Microscopy Without X-ray Optics

  3. The Universe Viewed in Gamma-Rays 1 Properties of Gamma-ray Bursts Localized by

    E-Print Network [OSTI]

    Enomoto, Ryoji

    The Universe Viewed in Gamma-Rays 1 Properties of Gamma-ray Bursts Localized by the HETE-2 and localize Gamma-ray bursts (GRBs) in wide field of view. HETE-2 have been localized about 20 GRBs per year hours after the burst. 1. The High Energy Transient Explorer 2 Gamma-ray burst (GRB) is the most

  4. X-ray Pulsations in the Supersoft X-ray Binary CAL 83

    E-Print Network [OSTI]

    P. C. Schmidtke; A. P. Cowley

    2005-09-28T23:59:59.000Z

    X-ray data reveal that the supersoft X-ray binary CAL 83 exhibits 38.4 minute pulsations at some epochs. These X-ray variations are similar to those found in some novae and are likely to be caused by nonradial pulsations the white dwarf. This is the first detection of pulsations in a classical supersoft X-ray binary.

  5. Microgap x-ray detector

    DOE Patents [OSTI]

    Wuest, C.R.; Bionta, R.M.; Ables, E.

    1994-05-03T23:59:59.000Z

    An x-ray detector is disclosed which provides for the conversion of x-ray photons into photoelectrons and subsequent amplification of these photoelectrons through the generation of electron avalanches in a thin gas-filled region subject to a high electric potential. The detector comprises a cathode (photocathode) and an anode separated by the thin, gas-filled region. The cathode may comprise a substrate, such a beryllium, coated with a layer of high atomic number material, such as gold, while the anode can be a single conducting plane of material, such as gold, or a plane of resistive material, such as chromium/silicon monoxide, or multiple areas of conductive or resistive material, mounted on a substrate composed of glass, plastic or ceramic. The charge collected from each electron avalanche by the anode is passed through processing electronics to a point of use, such as an oscilloscope. 3 figures.

  6. Microgap x-ray detector

    DOE Patents [OSTI]

    Wuest, Craig R. (Danville, CA); Bionta, Richard M. (Livermore, CA); Ables, Elden (Livermore, CA)

    1994-01-01T23:59:59.000Z

    An x-ray detector which provides for the conversion of x-ray photons into photoelectrons and subsequent amplification of these photoelectrons through the generation of electron avalanches in a thin gas-filled region subject to a high electric potential. The detector comprises a cathode (photocathode) and an anode separated by the thin, gas-filled region. The cathode may comprise a substrate, such a beryllium, coated with a layer of high atomic number material, such as gold, while the anode can be a single conducting plane of material, such as gold, or a plane of resistive material, such as chromium/silicon monoxide, or multiple areas of conductive or resistive material, mounted on a substrate composed of glass, plastic or ceramic. The charge collected from each electron avalanche by the anode is passed through processing electronics to a point of use, such as an oscilloscope.

  7. Cosmic Rays at the Knee

    E-Print Network [OSTI]

    Thomas K. Gaisser

    2006-08-25T23:59:59.000Z

    Several kinds of measurements are combined in an attempt to obtain a consistent estimate of the spectrum and composition of the primary cosmic radiation through the knee region. Assuming that the knee is a signal of the high-energy end of a galactic cosmic-ray population, I discuss possible signatures of a transition to an extra-galactic population and how they might be detected.

  8. The Diverse Environments of Gamma-Ray Bursts

    E-Print Network [OSTI]

    Perley, Daniel Alan

    2011-01-01T23:59:59.000Z

    Galaxies of Dark Gamma-Ray Bursts: Observational Constraintsof a Very Bright Gamma- Ray Burst in a Galactic Halo 3.11.3 Gamma-Ray Burst Classi?cation . . . . . . 1.4 Gamma-Ray

  9. X-ray Spectroscopy of Cooling Clusters

    E-Print Network [OSTI]

    J. R. Peterson; A. C. Fabian

    2005-12-21T23:59:59.000Z

    We review the X-ray spectra of the cores of clusters of galaxies. Recent high resolution X-ray spectroscopic observations have demonstrated a severe deficit of emission at the lowest X-ray temperatures as compared to that expected from simple radiative cooling models. The same observations have provided compelling evidence that the gas in the cores is cooling below half the maximum temperature. We review these results, discuss physical models of cooling clusters, and describe the X-ray instrumentation and analysis techniques used to make these observations. We discuss several viable mechanisms designed to cancel or distort the expected process of X-ray cluster cooling.

  10. X-ray transmissive debris shield

    DOE Patents [OSTI]

    Spielman, Rick B. (Albuquerque, NM)

    1996-01-01T23:59:59.000Z

    An X-ray debris shield for use in X-ray lithography that is comprised of an X-ray window having a layer of low density foam exhibits increased longevity without a substantial increase in exposure time. The low density foam layer serves to absorb the debris emitted from the X-ray source and attenuate the shock to the window so as to reduce the chance of breakage. Because the foam is low density, the X-rays are hardly attenuated by the foam and thus the exposure time is not substantially increased.

  11. X-ray lithography using holographic images

    DOE Patents [OSTI]

    Howells, Malcolm R. (Berkeley, CA); Jacobsen, Chris (Sound Beach, NY)

    1995-01-01T23:59:59.000Z

    A non-contact X-ray projection lithography method for producing a desired X-ray image on a selected surface of an X-ray-sensitive material, such as photoresist material on a wafer, the desired X-ray image having image minimum linewidths as small as 0.063 .mu.m, or even smaller. A hologram and its position are determined that will produce the desired image on the selected surface when the hologram is irradiated with X-rays from a suitably monochromatic X-ray source of a selected wavelength .lambda.. On-axis X-ray transmission through, or off-axis X-ray reflection from, a hologram may be used here, with very different requirements for monochromaticity, flux and brightness of the X-ray source. For reasonable penetration of photoresist materials by X-rays produced by the X-ray source, the wavelength X, is preferably chosen to be no more than 13.5 nm in one embodiment and more preferably is chosen in the range 1-5 nm in the other embodiment. A lower limit on linewidth is set by the linewidth of available microstructure writing devices, such as an electron beam.

  12. Hard x-ray imaging from explorer

    SciTech Connect (OSTI)

    Grindlay, J.E.; Murray, S.S.

    1981-11-01T23:59:59.000Z

    Coded aperture X-ray detectors were applied to obtain large increases in sensitivity as well as angular resolution. A hard X-ray coded aperture detector concept is described which enables very high sensitivity studies persistent hard X-ray sources and gamma ray bursts. Coded aperture imaging is employed so that approx. 2 min source locations can be derived within a 3 deg field of view. Gamma bursts were located initially to within approx. 2 deg and X-ray/hard X-ray spectra and timing, as well as precise locations, derived for possible burst afterglow emission. It is suggested that hard X-ray imaging should be conducted from an Explorer mission where long exposure times are possible.

  13. Techniques for synchronization of X-Ray pulses to the pump laser in an ultrafast X-Ray facility

    E-Print Network [OSTI]

    Corlett, J.N.; Doolittle, L.; Schoenlein, R.; Staples, J.; Wilcox, R.; Zholents, A.

    2003-01-01T23:59:59.000Z

    synchronization of ultrafast x-ray pulses produced in theAccurate timing of ultrafast x-ray probe pulses emitted fromOF X-RAY PULSES TO THE PUMP LASER IN AN ULTRAFAST X-RAY

  14. X-ray laser frequency near-doubling and generation of tunable coherent x rays in plasma

    E-Print Network [OSTI]

    Kaplan, Alexander

    X-ray laser frequency near-doubling and generation of tunable coherent x rays in plasma P. L plasmas in which efficient x-ray laser frequency near-doubling is expected for a number of available x-ray of coherent x rays and tunable optical radiation may result in tunable coherent x-ray radiation powerful

  15. Controlling X-rays With Light

    SciTech Connect (OSTI)

    Glover, Ernie; Hertlein, Marcus; Southworth, Steve; Allison, Tom; van Tilborg, Jeroen; Kanter, Elliot; Krassig, B.; Varma, H.; Rude, Bruce; Santra, Robin; Belkacem, Ali; Young, Linda

    2010-08-02T23:59:59.000Z

    Ultrafast x-ray science is an exciting frontier that promises the visualization of electronic, atomic and molecular dynamics on atomic time and length scales. A largelyunexplored area of ultrafast x-ray science is the use of light to control how x-rays interact with matter. In order to extend control concepts established for long wavelengthprobes to the x-ray regime, the optical control field must drive a coherent electronic response on a timescale comparable to femtosecond core-hole lifetimes. An intense field is required to achieve this rapid response. Here an intense optical control pulse isobserved to efficiently modulate photoelectric absorption for x-rays and to create an ultrafast transparency window. We demonstrate an application of x-ray transparencyrelevant to ultrafast x-ray sources: an all-photonic temporal cross-correlation measurement of a femtosecond x-ray pulse. The ability to control x-ray/matterinteractions with light will create new opportunities at current and next-generation x-ray light sources.

  16. X-ray Observations of Mrk 231

    E-Print Network [OSTI]

    T. J. Turner

    1998-08-10T23:59:59.000Z

    This paper presents new X-ray observations of Mrk 231, an active galaxy of particular interest due to its large infrared luminosity and the presence of several blueshifted broad absorption line (BAL) systems, a phenomenon observed in a small fraction of QSOs. A ROSAT HRI image of Mrk 231 is presented, this shows an extended region of soft X-ray emission, covering several tens of kpc, consistent with the extent of the host galaxy. An ASCA observation of Mrk 231 is also presented. Hard X-rays are detected but the data show no significant variability in X-ray flux. The hard X-ray continuum is heavily attenuated and X-ray column estimates range from ~ 2 x 10^{22} - 10^{23} cm^{-2} depending on whether the material is assumed to be neutral or ionized, and on the model assumed for the extended X-ray component. These ASCA data provide only the second hard X-ray spectrum of a BAL AGN presented to date. The broad-band spectral-energy-distribution of the source is discussed. While Mrk 231 is X-ray weak compared to Seyfert 1 galaxies, it has an optical-to-X-ray spectrum typical of a QSO.

  17. PHYSICAL PROCESSES SHAPING GAMMA-RAY BURST X-RAY AFTERGLOW LIGHT CURVES: THEORETICAL IMPLICATIONS FROM THE SWIFT X-RAY TELESCOPE OBSERVATIONS

    E-Print Network [OSTI]

    Zhang, Bing

    PHYSICAL PROCESSES SHAPING GAMMA-RAY BURST X-RAY AFTERGLOW LIGHT CURVES: THEORETICAL IMPLICATIONS August 15; accepted 2005 December 19 ABSTRACT With the successful launch of the Swift Gamma-Ray Burst component is consistent with the tail emission of the prompt gamma-ray bursts and/or the X-ray flares

  18. A cosmic ray hodoscope system

    E-Print Network [OSTI]

    Cantrell, Wallace Gene

    1965-01-01T23:59:59.000Z

    of these radiations, the muon, suffers small scattering in the atmosphere and therefore retains information about its history when it reaches the earth's surface. It is the properties of the muon that make it a useful particle in cosmic ray studies. Since the muon... deflections. In addition, the half-life of the muon is long enough, approximately 2 p sec, that a sizeable portion of those produced in the uppez atmosphere survive to ground level. The probability of survival of the muons is enhanced at higher energies...

  19. High-energy Cosmic Rays

    E-Print Network [OSTI]

    Thomas K. Gaisser; Todor Stanev

    2005-10-11T23:59:59.000Z

    After a brief review of galactic cosmic rays in the GeV to TeV energy range, we describe some current problems of interest for particles of very high energy. Particularly interesting are two features of the spectrum, the `knee' above $10^{15}$ eV and the `ankle' above $10^{18}$ eV. An important question is whether the highest energy particles are of extra-galactic origin and, if so, at what energy the transition occurs. A theme common to all energy ranges is use of nuclear abundances as a tool for understanding the origin of the cosmic radiation.

  20. Gamma Ray Burst Central Engines

    E-Print Network [OSTI]

    Todd A. Thompson

    2008-07-04T23:59:59.000Z

    I review aspects of the theory of long-duration gamma-ray burst (GRB) central engines. I focus on the requirements of any model; these include the angular momentum of the progenitor, the power, Lorentz factor, asymmetry, and duration of the flow, and both the association and the non-association with bright supernovae. I compare and contrast the collapsar and millisecond proto-magnetar models in light of these requirements. The ability of the latter model to produce a flow with Lorentz factor ~100 while simultaneously maintaining a kinetic luminosity of ~10^50 ergs/s for a timescale of ~10-100 s is emphasized.

  1. Lorentz Group in Ray Optics

    E-Print Network [OSTI]

    S. Baskal; E. Georgieva; Y. S. Kim; M. E. Noz

    2004-01-18T23:59:59.000Z

    It has been almost one hundred years since Einstein formulated his special theory of relativity in 1905. He showed that the basic space-time symmetry is dictated by the Lorentz group. It is shown that this group of Lorentz transformations is not only applicable to special relativity, but also constitutes the scientific language for optical sciences. It is noted that coherent and squeezed states of light are representations of the Lorentz group. The Lorentz group is also the basic underlying language for classical ray optics, including polarization optics, interferometers, the Poincare\\'e sphere, one-lens optics, multi-lens optics, laser cavities, as well multilayer optics.

  2. X-ray Imaging Workshop

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched FerromagnetismWaste and MaterialsWenjun1of EnergyX-ray Computed TomographyImaging

  3. X-ray fluorescence mapping

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched FerromagnetismWaste and MaterialsWenjun1of EnergyX-rayNew Materialsray

  4. X-Ray Science Education

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered energy consumption byAbout SRNL Home SRNL main campusMore thanX-Ray Imagingfeed

  5. Energetics of Gamma Ray Bursts

    E-Print Network [OSTI]

    Raul Jimenez; David Band; Tsvi Piran

    2001-03-16T23:59:59.000Z

    We determine the distribution of total energy emitted by gamma-ray bursts for bursts with fluences and distance information. Our core sample consists of eight bursts with BATSE spectra and spectroscopic redshifts. We extend this sample by adding four bursts with BATSE spectra and host galaxy R magnitudes. From these R magnitudes we calculate a redshift probability distribution; this method requires a model of the host galaxy population. From a sample of ten bursts with both spectroscopic redshifts and host galaxy R magnitudes (some do not have BATSE spectra) we find that the burst rate is proportional to the galaxy luminosity at the epoch of the burst. Assuming that the total energy emitted has a log-normal distribution, we find that the average emitted energy (assumed to be radiated isotropically) is $gamma iso} > = 1.3^{+1.2}_{-1.0} \\times 10^{53}$ ergs (for H$_0$ = 65 km s$^{-1}$ Mpc$^{-1}$, $\\Omega_m=0.3$ and $\\Omega_\\Lambda=0.7$); the distribution has a logarithmic width of $\\sigma_\\gamma=1.7^{+0.7}_{-0.3}$. The corresponding distribution of X-ray afterglow energy (for seven bursts) has $ = 4.0^{+1.6}_{-1.8} \\times 10^{51}$ergs and $\\sigma_X = 1.3^{+0.4}_{-0.3}$. For completeness, we also provide spectral fits for all bursts with BATSE spectra for which there were afterglow searches.

  6. Gamma-ray Burst Cosmology

    E-Print Network [OSTI]

    Wang, F Y; Liang, E W

    2015-01-01T23:59:59.000Z

    Gamma-ray bursts (GRBs) are the most luminous electromagnetic explosions in the Universe, which emit up to $8.8\\times10^{54}$ erg isotropic equivalent energy in the hard X-ray band. The high luminosity makes them detectable out to the largest distances yet explored in the Universe. GRBs, as bright beacons in the deep Universe, would be the ideal tool to probe the properties of high-redshift universe: including the cosmic expansion and dark energy, star formation rate, the reionization epoch and the metal enrichment history of the Universe. In this article, we review the luminosity correlations of GRBs, and implications for constraining the cosmological parameters and dark energy. Observations show that the progenitors of long GRBs are massive stars. So it is expected that long GRBs are tracers of star formation rate. We also review the high-redshift star formation rate derived from GRBs, and implications for the cosmic reionization history. The afterglows of GRBs generally have broken power-law spectra, so it...

  7. Cloud chamber visualization of primary cosmic rays

    SciTech Connect (OSTI)

    Earl, James A. [Department of Astronomy, University of Maryland, College Park MD (United States)

    2013-02-07T23:59:59.000Z

    From 1948 until 1963, cloud chambers were carried to the top of the atmosphere by balloons. From these flights, which were begun by Edward P. Ney at the University of Minnesota, came the following results: discovery of heavy cosmic ray nuclei, development of scintillation and cherenkov detectors, discovery of cosmic ray electrons, and studies of solar proton events. The history of that era is illustrated here by cloud chamber photographs of primary cosmic rays.

  8. Black Stars and Gamma Ray Bursts

    E-Print Network [OSTI]

    Tanmay Vachaspati

    2007-06-08T23:59:59.000Z

    Stars that are collapsing toward forming a black hole but are frozen near the Schwarzschild horizon are termed ``black stars''. Collisions of black stars, in contrast to black hole collisions, may be sources of gamma ray bursts, whose basic parameters are estimated quite simply and are found to be consistent with observed gamma ray bursts. Black star gamma ray bursts should be preceded by gravitational wave emission similar to that from the coalescence of black holes.

  9. High speed x-ray beam chopper

    DOE Patents [OSTI]

    McPherson, Armon (Oswego, IL); Mills, Dennis M. (Naperville, IL)

    2002-01-01T23:59:59.000Z

    A fast, economical, and compact x-ray beam chopper with a small mass and a small moment of inertia whose rotation can be synchronized and phase locked to an electronic signal from an x-ray source and be monitored by a light beam is disclosed. X-ray bursts shorter than 2.5 microseconds have been produced with a jitter time of less than 3 ns.

  10. X-ray populations in galaxies

    E-Print Network [OSTI]

    G. Fabbiano

    2005-11-09T23:59:59.000Z

    Today's sensistive, high resolution Chandra X-ray observations allow the study of many populations of X-ray sources. The traditional astronomical tools of photometric diagrams and luminosity functions are now applied to these populations, and provide the means for classifying the X-ray sources and probing their evolution. While overall stellar mass drives the amount of X-ray binaries in old stellar population, the amount of sources in star-forming galaxies is related to the star formation rate. Shart-lived, luminous, high mass binaries (HNXBs) dominate these young populations.

  11. X-RAY MICROBEAM SPEECH PRODUCTION DATABASE

    E-Print Network [OSTI]

    X-RAY MICROBEAM SPEECH PRODUCTION DATABASE USER'S HANDBOOK Version 1.0 (June 1994) prepared by John . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Chapter Two: XRMB History

  12. High-energy cosmic ray interactions

    SciTech Connect (OSTI)

    Engel, Ralph [Forschungszentrum Karlsruhe, P.O. Box 3640, 76021 Karlsruhe (Germany); Orellana, Mariana [Instituto Argentino de Radioastronomia (IAR), CCT La Plata (CONICET), C.C.5, 1894 Villa Elisa, Buenos Aires (Argentina); Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque, 1900 La Plata (Argentina); Reynoso, Matias M. [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes 3350, (7600) Mar del Plata (Argentina); Instituto de Investigaciones Fisicas de Mar del Plata, (UNMdP-CONICET) (Argentina); Vila, Gabriela S. [Instituto Argentino de Radioastronomia (IAR), CCT La Plata (CONICET), C.C.5, 1894 Villa Elisa, Buenos Aires (Argentina)

    2009-04-30T23:59:59.000Z

    Research into hadronic interactions and high-energy cosmic rays are closely related. On one hand--due to the indirect observation of cosmic rays through air showers--the understanding of hadronic multiparticle production is needed for deriving the flux and composition of cosmic rays at high energy. On the other hand the highest energy particles from the universe allow us to study the characteristics of hadronic interactions at energies far beyond the reach of terrestrial accelerators. This is the summary of three introductory lectures on our current understanding of hadronic interactions of cosmic rays.

  13. Gamma ray burst outflows and afterglows.

    E-Print Network [OSTI]

    Morsony, Brian J.

    2009-01-01T23:59:59.000Z

    ?? We carry out a theoretical investigation of jet propagation in Gamma Ray Bursts and examine the jitter radiation mechanism as a means of producing (more)

  14. X-ray laser microscope apparatus

    DOE Patents [OSTI]

    Suckewer, Szymon (Princeton, NJ); DiCicco, Darrell S. (Plainsboro, NJ); Hirschberg, Joseph G. (Coral Gables, FL); Meixler, Lewis D. (East Windsor, NJ); Sathre, Robert (Princeton, NJ); Skinner, Charles H. (Lawrenceville, NJ)

    1990-01-01T23:59:59.000Z

    A microscope consisting of an x-ray contact microscope and an optical microscope. The optical, phase contrast, microscope is used to align a target with respect to a source of soft x-rays. The source of soft x-rays preferably comprises an x-ray laser but could comprise a synchrotron or other pulse source of x-rays. Transparent resist material is used to support the target. The optical microscope is located on the opposite side of the transparent resist material from the target and is employed to align the target with respect to the anticipated soft x-ray laser beam. After alignment with the use of the optical microscope, the target is exposed to the soft x-ray laser beam. The x-ray sensitive transparent resist material whose chemical bonds are altered by the x-ray beam passing through the target mater GOVERNMENT LICENSE RIGHTS This invention was made with government support under Contract No. De-FG02-86ER13609 awarded by the Department of Energy. The Government has certain rights in this invention.

  15. Gamma-Ray Bursts and Particle Astrophysics

    E-Print Network [OSTI]

    B. Gendre

    2008-07-24T23:59:59.000Z

    Gamma-ray bursts are violent events occurring randomly in the sky. In this review, I will present the fireball model, proposed to explain the phenomenon of gamma-ray bursts. This model has important consequences for the production and observation at Earth of gravitational waves, high energy neutrinos, cosmic rays and high energy photons, and the second part of this review will be focused on these aspects. A last section will briefly discuss the topic of the use of gamma-ray bursts as standard candles and possible cosmological studies.

  16. Compound refractive X-ray lens

    DOE Patents [OSTI]

    Nygren, David R. (Berkeley, CA); Cahn, Robert (Walnut Creek, CA); Cederstrom, Bjorn (Traellborg, SE); Danielsson, Mats (Stocksund, SE); Vestlund, Jonas (Stockholm, SE)

    2000-01-01T23:59:59.000Z

    An apparatus and method for focusing X-rays. In one embodiment, his invention is a commercial-grade compound refractive X-ray lens. The commercial-grade compound refractive X-ray lens includes a volume of low-Z material. The volume of low-Z material has a first surface which is adapted to receive X-rays of commercially-applicable power emitted from a commercial-grade X-ray source. The volume of low-Z material also has a second surface from which emerge the X-rays of commercially-applicable power which were received at the first surface. Additionally, the commercial-grade compound refractive X-ray lens includes a plurality of openings which are disposed between the first surface and the second surface. The plurality of openings are oriented such that the X-rays of commercially-applicable power which are received at the first surface, pass through the volume of low-Z material and through the plurality openings. In so doing, the X-rays which emerge from the second surface are refracted to a focal point.

  17. X-Ray Science Division (XSD)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    X-Ray Science Division (XSD) Search Button About Welcome Overview Visiting the APS Mission & Goals Find People Organization Charts Committees Job Openings User Information...

  18. X-ray spectroscopy of neutron star low-mass X-ray binaries

    E-Print Network [OSTI]

    Krauss, Miriam Ilana

    2007-01-01T23:59:59.000Z

    In this thesis, I present work spanning a variety of topics relating to neutron star lowmass X-ray binaries (LMXBs) and utilize spectral information from X-ray observations to further our understanding of these sources. ...

  19. Ultraluminous X-ray Sources: The most extreme X-ray binaries

    E-Print Network [OSTI]

    ?umer, Slobodan

    1 Ultraluminous X-ray Sources: The most extreme X-ray binaries Luca Zampieri INAF ULXs ­ Lubiana ­ May 11, 2012- LZ #12;6 · X-ray observations of nearby galaxies show a population of pointlike, off-nuclear sources with L >> Ledd for 1 Msun (L>1.0e39 erg/s) UltraLuminous X-ray Sources (e

  20. X-ray Diffraction (XRD) 1.0 What is X-ray Diffraction

    E-Print Network [OSTI]

    Moeck, Peter

    X-ray Diffraction (XRD) · 1.0 What is X-ray Diffraction · 2.0 Basics of Crystallography · 3.0 Production of X-rays · 4.0 Applications of XRD · 5.0 Instrumental Sources of Error · 6.0 Conclusions #12 why the cleavage faces of crystals appear to reflect X-ray beams at certain angles of incidence (theta

  1. The Universe Viewed in Gamma-Rays 1 X-Ray and Gamma-Ray Emission from the PSR 1259-

    E-Print Network [OSTI]

    Enomoto, Ryoji

    threshold in the future projects. 1. Introduction PSR 1259-63 is a 48 ms radio pulsar orbiting a Be star. The pulsation is absent in the X-ray intensity. Only upper limits are reported for the high energy -ray emission accelerates electrons and positrons to the relativistic energies. We derive the energy distribution

  2. Are extragalactic gamma ray bursts the source of the highest energy cosmic rays?

    E-Print Network [OSTI]

    Arnon Dar

    1999-01-03T23:59:59.000Z

    Recent observations with the large air shower arrays of ultra high energy cosmic rays (UHECR) and recent measurements/estimates of the redshifts of gamma ray bursts (GRBs) seem to rule out extragalactic GRBs as the source of the cosmic rays that are observed near Earth, including those with the highest energies.

  3. Gravitational Waves versus X and Gamma Ray Emission in a Short Gamma-Ray Burst

    E-Print Network [OSTI]

    F. G. Oliveira; Jorge A. Rueda; Remo Ruffini

    2014-03-28T23:59:59.000Z

    The recent progress in the understanding the physical nature of neutron star equilibrium configurations and the first observational evidence of a genuinely short gamma-ray burst, GRB 090227B, allows to give an estimate of the gravitational waves versus the X and Gamma-ray emission in a short gamma-ray burst.

  4. ON THE RECENTLY DISCOVERED CORRELATIONS BETWEEN GAMMA-RAY AND X-RAY PROPERTIES OF GAMMA-RAY BURSTS

    SciTech Connect (OSTI)

    Dado, Shlomo; Dar, Arnon [Physics Department, Technion, Haifa 32000 (Israel)

    2013-09-20T23:59:59.000Z

    Recently, many correlations between the prompt {gamma}-ray emission properties and the X-ray afterglow properties of gamma-ray bursts (GRBs) have been inferred from a comprehensive analysis of the X-ray light curves of more than 650 GRBs measured with the Swift X-Ray Telescope (Swift/XRT) during the years 2004-2010. We show that these correlations are predicted by the cannonball (CB) model of GRBs. They result from the dependence of GRB observables on the bulk motion Lorentz factor and viewing angle of the jet of highly relativistic plasmoids (CBs) that produces the observed radiations by interaction with the medium through which it propagates. Moreover, despite their different physical origins, long GRBs (LGRBs) and short-hard bursts (SHBs) in the CB model share similar kinematic correlations, which can be combined into triple correlations satisfied by both LGRBs and SHBs.

  5. SLAC Cosmic Ray Telescope Facility

    SciTech Connect (OSTI)

    Va'vra, J.

    2010-02-15T23:59:59.000Z

    SLAC does not have a test beam for the HEP detector development at present. We have therefore created a cosmic ray telescope (CRT) facility, which is presently being used to test the FDIRC prototype. We have used it in the past to debug this prototype with the original SLAC electronics before going to the ESA test beam. Presently, it is used to test a new waveform digitizing electronics developed by the University of Hawaii, and we are also planning to incorporate the new Orsay TDC/ADC electronics. As a next step, we plan to put in a full size DIRC bar box with a new focusing optics, and test it together with a final SuberB electronics. The CRT is located in building 121 at SLAC. We anticipate more users to join in the future. This purpose of this note is to provide an introductory manual for newcomers.

  6. Results from the Milagro Gamma-Ray Observatory

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    V energies, and a search for transient emission above 100 GeV from gamma-ray bursts. 1 Introduction remnants and gamma-ray bursts (GRB). Gamma rays are also produced when high-energy cosmic rays interactResults from the Milagro Gamma-Ray Observatory E. Blaufuss for the Milagro Collaboration a,1 , a

  7. X-ray Practicals Series 1 Advanced Data Reduction

    E-Print Network [OSTI]

    Meagher, Mary

    X-ray Practicals Series 1 Advanced Data Reduction Instructor J. Reibenspies, Ph. D. Nattamai Bhuvanesh, Ph.D. Version 1.0.0 #12;X-ray Practicals Series 2 #12;X-ray Practicals Series 3 #12;X-ray is good. The y direction is shifting the most, but the shift is ok #12;X-ray Practicals Series 5 Other

  8. Temporally Coherent Interactive Ray Tracing William Martin

    E-Print Network [OSTI]

    Utah, University of

    systems use a sparse sam- pling of the image (approximately one ray per pixel) and relatively small image in point sam- pled imagery by targeting new rays to intersection points from previous frames. Remaining to cause sub-pixel detail in rendered images, leading to temporal aliasing. We believe this is the dominant

  9. X-ray source populations in galaxies

    E-Print Network [OSTI]

    G. Fabbiano

    2005-11-16T23:59:59.000Z

    Today's sensitive, high-resolution X-ray observations allow the study of populations of X-ray sources, in the luminosity range of Galactic X-ray binaries, in galaxies as distant as 20-30 Mpc. The traditional astronomical tools of photometric diagrams and luminosity functions are now applied to these populations, providing a direct probe of the evolved binary component of different stellar populations. The study of the X-ray populations of E and S0 galaxies has revamped the debate on the formation and evolution of low-mass X-ray binaries (LMXBs) and on the role of globular clusters in these processes. While overall stellar mass drives the amount of X-ray binaries in old stellar populations, the amount of sources in star forming galaxies is related to the star formation rate. Short-lived, luminous, high-mass binaries (HMXBs) dominate these young populations. The most luminous sources in these systems are the debated ULXs, which have been suggested to be ~100-1000 Msol black holes, but could alternatively include a number of binaries with stellar mass black holes. Very soft sources have also been discovered in many galaxies and their nature is currently being debated. Observations of the deep X-ray sky, and comparison with deep optical surveys, are providing the first evidence of the X-ray evolution of galaxies.

  10. Phased Contrast X-Ray Imaging

    ScienceCinema (OSTI)

    Erin Miller

    2012-12-31T23:59:59.000Z

    The Pacific Northwest National Laboratory is developing a range of technologies to broaden the field of explosives detection. Phased contrast X-ray imaging, which uses silicon gratings to detect distortions in the X-ray wave front, may be applicable to mail or luggage scanning for explosives; it can also be used in detecting other contraband, small-parts inspection, or materials characterization.

  11. Gamma-Ray Pulsar Studies With GLAST

    SciTech Connect (OSTI)

    Thompson, D.J.; /NASA, Goddard

    2011-11-23T23:59:59.000Z

    Some pulsars have their maximum observable energy output in the gamma-ray band, offering the possibility of using these high-energy photons as probes of the particle acceleration and interaction processes in pulsar magnetospheres. After an extended hiatus between satellite missions, the recently-launched AGILE mission and the upcoming Gamma-ray Large Area Space Telescope (GLAST) Large Area Telescope (LAT) will allow gamma-ray tests of the theoretical models developed based on past discoveries. With its greatly improved sensitivity, better angular resolution, and larger energy reach than older instruments, GLAST LAT should detect dozens to hundreds of new gamma-ray pulsars and measure luminosities, light curves, and phase-resolved spectra with unprecedented resolution. It will also have the potential to find radio-quiet pulsars like Geminga, using blind search techniques. Cooperation with radio and X-ray pulsar astronomers is an important aspect of the LAT team's planning for pulsar studies.

  12. The HAWC Gamma-Ray Observatory: Sensitivity to Steady and Transient Sources of Gamma Rays

    E-Print Network [OSTI]

    Abeysekara, A U; Alvarez, C; lvarez, J D; Arceo, R; Arteaga-Velzquez, J C; Solares, H A Ayala; Barber, A S; Baughman, B M; Bautista-Elivar, N; Belmont, E; BenZvi, S Y; Berley, D; Rosales, M Bonilla; Braun, J; Caballero-Lopez, R A; Caballero-Mora, K S; Carramiana, A; Castillo, M; Cotti, U; Cotzomi, J; de la Fuente, E; De Len, C; DeYoung, T; Hernandez, R Diaz; Daz-Vlez, J C; Dingus, B L; DuVernois, M A; Ellsworth, R W; Fernandez, A; Fiorino, D W; Fraija, N; Galindo, A; Garfias, F; Gonzlez, L X; Gonzlez, M M; Goodman, J A; Grabski, V; Gussert, M; Hampel-Arias, Z; Hui, C M; Hntemeyer, P; Imran, A; Iriarte, A; Karn, P; Kieda, D; Kunde, G J; Lara, A; Lauer, R J; Lee, W H; Lennarz, D; Vargas, H Len; Linares, E C; Linnemann, J T; Longo, M; Luna-GarcIa, R; Marinelli, A; Martinez, H; Martinez, O; Martnez-Castro, J; Matthews, J A J; Miranda-Romagnoli, P; Moreno, E; Mostaf, M; Nava, J; Nellen, L; Newbold, M; Noriega-Papaqui, R; Oceguera-Becerra, T; Patricelli, B; Pelayo, R; Prez-Prez, E G; Pretz, J; Rivire, C; Rosa-Gonzlez, D; Salazar, H; Salesa, F; Sanchez, F E; Sandoval, A; Santos, E; Schneider, M; Silich, S; Sinnis, G; Smith, A J; Sparks, K; Springer, R W; Taboada, I; Toale, P A; Tollefson, K; Torres, I; Ukwatta, T N; Villaseor, L; Weisgarber, T; Westerhoff, S; Wisher, I G; Wood, J; Yodh, G B; Younk, P W; Zaborov, D; Zepeda, A; Zhou, H

    2013-01-01T23:59:59.000Z

    The High-Altitude Water Cherenkov (HAWC) Gamma-Ray Observatory is designed to record air showers produced by cosmic rays and gamma rays between 100 GeV and 100 TeV. Because of its large field of view and high livetime, HAWC is well-suited to measure gamma rays from extended sources, diffuse emission, and transient sources. We describe the sensitivity of HAWC to emission from the extended Cygnus region as well as other types of galactic diffuse emission; searches for flares from gamma-ray bursts and active galactic nuclei; and the first measurement of the Crab Nebula with HAWC-30.

  13. Quantitative Measurements of X-ray Intensity

    SciTech Connect (OSTI)

    Haugh, M. J., Schneider, M.

    2011-09-01T23:59:59.000Z

    This chapter describes the characterization of several X-ray sources and their use in calibrating different types of X-ray cameras at National Security Technologies, LLC (NSTec). The cameras are employed in experimental plasma studies at Lawrence Livermore National Laboratory (LLNL), including the National Ignition Facility (NIF). The sources provide X-rays in the energy range from several hundred eV to 110 keV. The key to this effort is measuring the X-ray beam intensity accurately and traceable to international standards. This is accomplished using photodiodes of several types that are calibrated using radioactive sources and a synchrotron source using methods and materials that are traceable to the U.S. National Institute of Standards and Technology (NIST). The accreditation procedures are described. The chapter begins with an introduction to the fundamental concepts of X-ray physics. The types of X-ray sources that are used for device calibration are described. The next section describes the photodiode types that are used for measuring X-ray intensity: power measuring photodiodes, energy dispersive photodiodes, and cameras comprising photodiodes as pixel elements. Following their description, the methods used to calibrate the primary detectors, the power measuring photodiodes and the energy dispersive photodiodes, as well as the method used to get traceability to international standards are described. The X-ray source beams can then be measured using the primary detectors. The final section then describes the use of the calibrated X-ray beams to calibrate X-ray cameras. Many of the references are web sites that provide databases, explanations of the data and how it was generated, and data calculations for specific cases. Several general reference books related to the major topics are included. Papers expanding some subjects are cited.

  14. X-RAY EMISSION FROM PLANETS AND COMETS: RELATIONSHIP WITH SOLAR X-RAYS AND SOLAR WIND

    E-Print Network [OSTI]

    ?stgaard, Nikolai

    with the occurrence of solar X-ray flare, when light travel time delay is accounted, suggesting that X-rays fromX-RAY EMISSION FROM PLANETS AND COMETS: RELATIONSHIP WITH SOLAR X-RAYS AND SOLAR WIND ANIL BHARDWAJ Flight center, Greenbelt, MD 20771, USA Scattering of solar X-ray radiation mainly produces the non

  15. CONSTRAINTS ON VERY HIGH ENERGY GAMMA-RAY EMISSION FROM GAMMA-RAY BURSTS R. Atkins,1,2

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    CONSTRAINTS ON VERY HIGH ENERGY GAMMA-RAY EMISSION FROM GAMMA-RAY BURSTS R. Atkins,1,2 W. Benbow,3 emission from gamma-ray bursts (GRBs) during the prompt emission phase. Detection of >100 GeV counterparts on potential GRB models. Subject headinggs: gamma rays: bursts -- gamma rays: observations 1. INTRODUCTION

  16. The Universe Viewed in Gamma-Rays 1 Toward Ultra Short Gamma Ray Burst Ground Based De-

    E-Print Network [OSTI]

    Enomoto, Ryoji

    The Universe Viewed in Gamma-Rays 1 Toward Ultra Short Gamma Ray Burst Ground Based De- tection- liminary data taking started in November 2002. 1. Introduction Gamma-ray bursts observed with space Tcherenkovlightfromoneshower Few 100MeV gamma-rays Fig. 1. In an imaging telescope, -ray bursts should appear as a Cherenkov

  17. X-Ray Diffraction The X-Ray Diffraction facility is equipped with state-of-the-art

    E-Print Network [OSTI]

    Birmingham, University of

    X-Ray Diffraction The X-Ray Diffraction facility is equipped with state-of-the-art diffractometers offering both single crystal and powder X-Ray diffraction. Powder X-Ray Diffraction High resolution data For more details on powder X-Ray analysis contact Dr J Hriljac on 0121 414 4458 or email: j

  18. Novel X-Ray Imaging Opportunities for the RPI Linear Accelerator's Tunable, Quasi-monochromatic X-ray Source

    E-Print Network [OSTI]

    Danon, Yaron

    Novel X-Ray Imaging Opportunities for the RPI Linear Accelerator's Tunable, Quasi-monochromatic X-ray of an intense, tunable, polarized, and quasi-monochromatic X-ray source has been ongoing at Rensselaer Polytechnic Institute since 2001 [1, 2, 3, 4, 5, 6]. This X-ray source, known as Parametric X-rays (PXR

  19. ON THE X-RAY OUTBURSTS OF TRANSIENT ANOMALOUS X-RAY PULSARS AND SOFT GAMMA-RAY REPEATERS

    SciTech Connect (OSTI)

    Cal Latin-Small-Letter-Dotless-I skan, Sirin; Ertan, Uenal [Sabanc Latin-Small-Letter-Dotless-I University, Orhanl Latin-Small-Letter-Dotless-I -Tuzla, Istanbul, 34956 (Turkey)

    2012-10-20T23:59:59.000Z

    We show that the X-ray outburst light curves of four transient anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs), namely, XTE J1810-197, SGR 0501+4516, SGR 1627-41, and CXOU J164710.2-455216, can be produced by the fallback disk model that was also applied to the outburst light curves of persistent AXPs and SGRs in our earlier work. The model solves the diffusion equation for the relaxation of a disk that has been pushed back by a soft gamma-ray burst. The sets of main disk parameters used for these transient sources are very similar to each other and to those employed in our earlier models of persistent AXPs and SGRs. There is a characteristic difference between the X-ray outburst light curves of transient and persistent sources. This can be explained by the differences in the disk surface density profiles of the transient and persistent sources in quiescence indicated by their quiescent X-ray luminosities. Our results imply that a viscous disk instability operating at a critical temperature in the range of {approx}1300-2800 K is a common property of all fallback disks around AXPs and SGRs. The effect of the instability is more pronounced and starts earlier for the sources with lower quiescent luminosities, which leads to the observable differences in the X-ray enhancement light curves of transient and persistent sources. A single active disk model with the same basic disk parameters can account for the enhancement phases of both transient and persistent AXPs and SGRs. We also present a detailed parameter study to show the effects of disk parameters on the evolution of the X-ray luminosity of AXPs and SGRs in the X-ray enhancement phases.

  20. X-ray Absorption Spectroscopy of Biologically Relevant Systems

    E-Print Network [OSTI]

    Uejio, Janel Sunayo

    2010-01-01T23:59:59.000Z

    308, Messer, B. M. X-ray Absorption Spectroscopy of AqueousSarcosine via X-ray Absorption Spectroscopy 5.1 Introductionwith Carboxylate by X-Ray Absorption Spectroscopy of Liquid

  1. A history of gamma ray bursts and other astronomical conundrums

    E-Print Network [OSTI]

    Trimble, V

    2006-01-01T23:59:59.000Z

    V. Trimble, in Gamma Ray Bursts: 30 Years of Discovery,V. Trimble, in Gamma Ray Bursts, Ed. C. Ho et al. ,A History of Gamma Ray Bursts and Other Astronomical

  2. Observations of Gamma-Ray Bursts at Extreme Energies

    E-Print Network [OSTI]

    Aune, Taylor

    2012-01-01T23:59:59.000Z

    of Gamma-Ray Bursts . . . . . . . . . . . . . Redshift-CRUZ OBSERVATIONS OF GAMMA-RAY BURSTS AT EXTREME ENERGIES AAncient Unvierse with Gamma-Ray Bursts, pages 330333. AIP,

  3. Biological Imaging by Soft X-Ray Diffraction Microscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biological Imaging by Soft X-Ray Diffraction Microscopy Biological Imaging by Soft X-Ray Diffraction Microscopy Print Wednesday, 30 November 2005 00:00 Electron and x-ray...

  4. High-Energy Neutrinos from Cosmic Rays

    E-Print Network [OSTI]

    F. Halzen

    2002-06-17T23:59:59.000Z

    We introduce neutrino astronomy from the observational fact that Nature accelerates protons and photons to energies in excess of 10^{20} and 10^{13} eV, respectively. Although the discovery of cosmic rays dates back close to a century, we do not know how and where they are accelerated. We review the facts as well as the speculations about the sources. Among these gamma ray bursts and active galaxies represent well-motivated speculations because these are also the sources of the highest energy gamma rays, with emission observed up to 20 TeV, possibly higher. We discuss why cosmic accelerators are also expected to be cosmic beam dumps producing high-energy neutrino beams associated with the highest energy cosmic rays. Cosmic ray sources may produce neutrinos from MeV to EeV energy by a variety of mechanisms. The important conclusion is that, independently of the specific blueprint of the source, it takes a kilometer-scale neutrino observatory to detect the neutrino beam associated with the highest energy cosmic rays and gamma rays. The technology for commissioning such instruments exists.

  5. Neutrinos and Gamma Rays from Galaxy Clusters

    E-Print Network [OSTI]

    Brandon Wolfe; Fulvio Melia; Roland M. Crocker; Raymond R. Volkas

    2008-07-04T23:59:59.000Z

    The next generation of neutrino and gamma-ray detectors should provide new insights into the creation and propagation of high-energy protons within galaxy clusters, probing both the particle physics of cosmic rays interacting with the background medium and the mechanisms for high-energy particle production within the cluster. In this paper we examine the possible detection of gamma-rays (via the GLAST satellite) and neutrinos (via the ICECUBE and Auger experiments) from the Coma cluster of galaxies, as well as for the gamma-ray bright clusters Abell 85, 1758, and 1914. These three were selected from their possible association with unidentified EGRET sources, so it is not yet entirely certain that their gamma-rays are indeed produced diffusively within the intracluster medium, as opposed to AGNs. It is not obvious why these inconspicuous Abell-clusters should be the first to be seen in gamma-rays, but a possible reason is that all of them show direct evidence of recent or ongoing mergers. Their identification with the EGRET gamma-ray sources is also supported by the close correlation between their radio and (purported) gamma-ray fluxes. Under favorable conditions (including a proton spectral index of 2.5 in the case of Abell 85, and sim 2.3 for Coma, and Abell 1758 and 1914), we expect ICECUBE to make as many as 0.3 neutrino detections per year from the Coma cluster of galaxies, and as many as a few per year from the Abell clusters 85, 1758, and 1914. Also, Auger may detect as many as 2 events per decade at ~ EeV energies from these gamma-ray bright clusters.

  6. The Cosmic Ray Distribution in Sagittarius B

    E-Print Network [OSTI]

    Roland M. Crocker; David Jones; Raymond J. Protheroe; Juergen Ott; Ron Ekers; Fulvio Melia; Todor Stanev; Anne Green

    2007-03-23T23:59:59.000Z

    The HESS instrument has observed a diffuse flux of ~ TeV gamma rays from a large solid angle around the Galactic center (GC). This emission is correlated with the distribution of gas in the region suggesting that the gamma rays originate in collisions between cosmic ray hadrons (CRHs) and ambient matter. Of particular interest, HESS has detected gamma rays from the Sagittarius (Sgr) B Molecular Cloud Complex. Prompted by the suggestion of a hadronic origin for the gamma rays, we have examined archival 330 and 74 MHz Very Large Array radio data and 843 MHz Sydney University Molonglo Sky Survey data covering Sgr B, looking for synchrotron emission from secondary electrons and positrons (expected to be created in the same interactions that supply the observed gamma rays). Intriguingly, we have uncovered non-thermal emission, but at a level exceeding expectation. Adding to the overall picture, recent observations by the Atacama Pathfinder Experiment telescope show that the cosmic ray ionization rate is ten times greater in the Sgr B2 region of Sgr B than the local value. Lastly, Sgr B2 is also a very bright X-ray source. We examine scenarios for the spectra of CRHs and/or primary electrons that would reconcile all these different data. We determine that (i) a hard (~ E^-2.2), high-energy (> TeV) population CRHs is unavoidably required by the HESS gamma ray data and (ii) the remaining broad-band, non-thermal phenomenology is explained either by a rather steep (~ E^-2.9) spectrum of primary electrons or a (~ E^-2.7) population of CRHs. No single, power-law population of either leptons or hadrons can explain the totality of broadband, non-thermal Sgr B phenomenology.

  7. Hard X-ray Fluorescence Measurements of Heteroepitaxial Solid...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hard X-ray Fluorescence Measurements of Heteroepitaxial Solid Oxide Fuel Cell Cathode Materials. Hard X-ray Fluorescence Measurements of Heteroepitaxial Solid Oxide Fuel Cell...

  8. Studies of meutron star X-ray binaries

    E-Print Network [OSTI]

    Thompson, Thomas W. J.

    2008-01-01T23:59:59.000Z

    by type I bursts or gamma-ray bursts (GRBs), produce aspread function (PSF). Gamma-ray bursts produce a similar

  9. RAY AND WAVE OPTICS OF INTEGRABLE AND STOCHASTIC SYSTEMS

    E-Print Network [OSTI]

    McDonald, S.W.

    2010-01-01T23:59:59.000Z

    18-22, 1979 RAY AND WAVE OPTICS OF INTEGRABLE AND STOCHASTICof the geometrical optics (ray Hamiltonian) system derivedthe classical (geometrical optics) system (1) and the state6

  10. Using X-Ray Computed Tomography in Pore Structure Characterization...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Using X-Ray Computed Tomography in Pore Structure Characterization for a Berea Sandstone: Resolution Effect. Using X-Ray Computed Tomography in Pore Structure Characterization for...

  11. Cosmic-ray induced gamma-ray emission from the starburst galaxy NGC 253

    SciTech Connect (OSTI)

    Wang, Xilu; Fields, Brian D. [Department of Astronomy, MC-221, 1002 W. Green Street, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)

    2014-05-09T23:59:59.000Z

    Cosmic rays in galaxies interact with the interstellar medium and give us a direct view of nuclear and particle interactions in the cosmos. For example, cosmic-ray proton interactions with interstellar hydrogen produce gamma rays via PcrPism??{sup 0}???. For a 'normal' star-forming galaxy like the Milky Way, most cosmic rays escape the Galaxy before such collisions, but in starburst galaxies with dense gas and huge star formation rate, most cosmic rays do suffer these interactions [1,2]. We construct a 'thick-target' model for starburst galaxies, in which cosmic rays are accelerated by supernovae, and escape is neglected. This model gives an upper limit to the gamma-ray emission. Only two free parameters are involved in the model: cosmic-ray proton acceleration energy rate from supernova and the proton injection spectral index. The pionic gamma-radiation is calculated from 10 MeV to 10 TeV for the starburst galaxy NGC 253, and compared to Fermi and HESS data. Our model fits NGC 253 well, suggesting that cosmic rays in this starburst are in the thick target limit, and that this galaxy is a gamma-ray calorimeter.

  12. X-Ray Physics in Confinement

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched FerromagnetismWaste and MaterialsWenjun1of Energy WorldwideX-RayX-RayX-Ray

  13. Tuesday, March 16, 2010 On Box Models

    E-Print Network [OSTI]

    Toohey, Darin W.

    to illustrate some of the basics of box models that are used frequently in the field of atmospheric chemistry L". You can guess that it was named after Marie Curie, someone who studied radioactive elements. #12 to exposure to contaminants. One tool that modelers use to assess exposure to pollutants is the "box model

  14. JUCAV Deck Handling Tuesday, December 12, 2006

    E-Print Network [OSTI]

    Austin, Mark

    ........................................................................................................19 LTSA........................................................................................... 20...........................................................................................................21 LTSA: MSC High Level ...............................................................................................22 LTSA: LTS Diagrams

  15. In The News Tuesday, April 5, 2011

    E-Print Network [OSTI]

    Arizona, University of

    . Daniel Von Hoff Pr-usa.net 04/05/2011 View Clip Kings of CABG: Surgeons Adapt Methods for Patients Which Serves All Of Arizona, Except For Maricopa County KMSB-TV 04/04/2011 Kids leave hospital after

  16. Tuesday, July 19, 2011 New England

    E-Print Network [OSTI]

    Nightingale, Peter

    ! Let's get ENERGY from wind and sun and stars, Ride more bicycles and drive electric cars, Let without those HORMONES placed inside. We like fish without PCB's And our forests to have TREE-ses, We

  17. Water from Wastewater Tuesday, September 24, 2013

    E-Print Network [OSTI]

    Zhang, Junshan

    change and global population growth demand creative and low-energy approaches to sustaining water and Education program that links five universities in two water-stressed regions of the world (Southwest U.S. and southeast Australia). This PIRE grant seeks to develop low-energy options for improving water productivity

  18. Geometry #2 Before Tuesday, August 28

    E-Print Network [OSTI]

    Lee, Carl

    with Google SketchUp and submit it through the forum "Sharing SketchUp Sketches." 3. Read Dunham Chapter 1

  19. Tuesday, February 8, 2011 Chemical Cycles

    E-Print Network [OSTI]

    Toohey, Darin W.

    , but can even happen in the UV-A region of the spectrum (l > 320 nm). DNA damage occurs in the UV-B region odor of electrical matter" in the description of the discharge of air. Note this was before it was accepted that oxygen was even a component of air! #12;Officially named as a chemical in 1840 by Christian

  20. In The News Tuesday, June 5, 2012

    E-Print Network [OSTI]

    Arizona, University of

    Control Center) 06/05/2012 KOLD-TV View Clip The Future of Joint Resurfacing (Arizona Arthritis Center Komen hoping for a lift from summer fundraisers (Arizona Cancer Center) 06/04/2012 Arizona Daily Star transplant (University of Arizona Medical Center) 06/01/2012 WDAM-TV View Clip #12;

  1. Sandia National Laboratories: Tuesday September 9, 2014

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (NESL) Brayton Lab SCO2 Brayton Cycle Technology Videos Heat Exchanger Development Diffusion Bonding Characterization Mechanical Testing Deep Borehole Disposal Nuclear...

  2. Complimentary Continental breakfast Tuesday and Wednesday mornings

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2011 Wind Turbine Reliability Workshop August 2-3, 2011 hosted by Sandia National Laboratories at the Albuquerque Marriott Pyramid A limited block of rooms, at special rates, is...

  3. MONDAY TUESDAY WEDNESDAY THURSDAY FRIDAY Indoor Cycling

    E-Print Network [OSTI]

    Kulp, Mark

    -sculpting exercises and high-energy cardio work with Latin-infused Zumba moves to create a calorie-torching, strength

  4. FOR IMMEDIATE RELEASE TUESDAY, APRIL 29, 2008

    E-Print Network [OSTI]

    and rising energy consumption ­ plus escalating costs for new power sources ­ the Taskforce seeks to explore supply. Energy efficiency is still the most economical resource. All of us must work to maximize with other industry leaders on Energy Efficiency Taskforce PORTLAND, Ore. ­ Pacific Power, the Northwest

  5. BOARD OF GOVERNORS Tuesday, January 27, 2009

    E-Print Network [OSTI]

    Pedersen, Tom

    . Howard Brunt, Prof. Jamie Cassels, Ms. Gayle Gorrill, Dr. Valerie Kuehne, Ms. Morag MacNeil. 1. Approval

  6. BOARD OF GOVERNORS Tuesday, November 29, 2005

    E-Print Network [OSTI]

    Pedersen, Tom

    :Prof. Jamie Cassels, Mr. Jack Falk, Dr. Valerie Kuehne, Dr. Martin Taylor, Ms. Morag MacNeil 1. Approval. Lynda Farmer for Dr. Valerie Kuehne and Ms. Shannon von Kaldenberg, #12;Board of Governors 2 Minutes

  7. BOARD OF GOVERNORS Tuesday, May 29, 2007

    E-Print Network [OSTI]

    Pedersen, Tom

    . Jamie Cassels, Ms. Gayle Gorrill, Dr. Valerie Kuehne Ms. Morag MacNeil, Mr. Gerald Robson, Dr BC re: TILMA VicePresident External Relations Valerie Kuehne reported that Cindy Paquette, the new

  8. BOARD OF GOVERNORS Tuesday, September 27, 2005

    E-Print Network [OSTI]

    Pedersen, Tom

    . By Invitation: Prof. Jamie Cassels, Mr. Jack Falk, Dr. Valerie Kuehne, Dr. Martin Taylor, Ms. Kate

  9. BOARD OF GOVERNORS Tuesday, September 29, 2009

    E-Print Network [OSTI]

    Pedersen, Tom

    . Jamie Cassels, Ms. Gayle Gorrill, Dr. Valerie Kuehne, Ms. Morag MacNeil 1. Approval of Agenda The agenda

  10. BOARD OF GOVERNORS Tuesday, November 28, 2006

    E-Print Network [OSTI]

    Pedersen, Tom

    : Prof. Jamie Cassels, Ms. Tracy Corbett, Dr. Valerie Kuehne, Ms. Kristi Simpson, Dr. Martin. Mr. Donald and Dr. Kuehne thanked Board members for their participation and support for the event

  11. BOARD OF GOVERNORS Tuesday, June 26, 2007

    E-Print Network [OSTI]

    Pedersen, Tom

    . By Invitation: Prof. Jamie Cassels, Mr. Neil Connelly, Ms. Gayle Gorrill, Dr. Valerie Kuehne, Ms. Morag Mac

  12. BOARD OF GOVERNORS Tuesday, May 27, 2008

    E-Print Network [OSTI]

    Pedersen, Tom

    Gorrill, Dr. Valerie Kuehne, Ms. Morag MacNeil. 1. Approval of Agenda The agenda was declared adopted

  13. BOARD OF GOVERNORS Tuesday, November 25, 2008

    E-Print Network [OSTI]

    Pedersen, Tom

    . Valerie Kuehne, Ms. Morag MacNeil, Mr. Peter Zacour. 1. Approval of Agenda The agenda was declared. Kuehne's team. CONSENT 5. University Operations and Facilities Committee a) Report on Undergraduate

  14. BOARD OF GOVERNORS Tuesday, September 26, 2006

    E-Print Network [OSTI]

    Pedersen, Tom

    Committee a) University of Victoria Staff Pension Plan Financial Statements for the Year ended December of Victoria Staff Pension Plan for the year ended December 31, 2005 b) Graduate Students' Society Extended dated August 24, 2006 from the Graduate Students' Society to the VicePresident Finance and Operations

  15. In The News Tuesday, April 26, 2011

    E-Print Network [OSTI]

    Arizona, University of

    , a specialist in oncology nutrition at the Arizona Cancer Center) Green Valley News 04/25/2011 View Clip Snooze/26/2011 Subscription required #12;Research from University of Arizona Broadens Understanding of DNA Research (D.K. Sun at the University of Arizona who also serves as Director of the Insomnia Clinic at the University Medical Center

  16. In The News Tuesday, January 3, 2012

    E-Print Network [OSTI]

    Arizona, University of

    events (University of Arizona Medical Center) 01/02/2012 Green Valley News View Clip Tucson medical/30/2011 Daily News-Sun View Clip Hospital goes tobacco-free (University of Arizona Medical Center) 12 by Monday (Arizona Cancer Center) 12/30/2011 YourWestValley.com View Clip Be a little selfish this holiday

  17. In The News Tuesday, January 18, 2011

    E-Print Network [OSTI]

    Arizona, University of

    of the Arizona Cancer Center) 01/18/2011 East Valley Tribune View Clip FOR WHAT IS NEXT OUT OF TUCSON, WE Star - Online Text | View Clip State can't fill Giffords 'vacancy' 01/18/2011 Arizona Daily Sun Text CAUGHT BY VIDEO CAMERAS 01/18/2011 Baltimore Sun Text Arizona's University Medical Center Sues HHS Over

  18. In The News Tuesday, March 27, 2012

    E-Print Network [OSTI]

    Arizona, University of

    of Arizona in TucsoN) 03/26/2012 CNN.com View Clip Interpreting Biomarkers During Percutaneous Coronary Intervention: The Need to Reevaluate Our Approach (Joseph S. Alpert, MD; Allan S. Jaffe, MD) 03

  19. In The News Tuesday, December 07, 2010

    E-Print Network [OSTI]

    Arizona, University of

    /07/2010 KOLD-TV - Online View Clip Research from University of Arizona in microelectromechanical systems from homogeneous cell suspensions," scientists writing in the Journal of Microelectromechanical Systems. Journal of Microelectromechanical Systems, 2010;19(4):752-763). Additional information can be obtained

  20. Tuesday Webcasts for Industry | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |Energy Usage »of EnergyThe EnergyDepartment7Department ofDepartment

  1. Tuesday, December 23, 2008 | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |Energy Usage »of EnergyThe EnergyDepartment7Department

  2. Deans' Council Minutes: Tuesday, October 25, 2011

    E-Print Network [OSTI]

    Dyer, Bill

    the Montana Weatherization Training Center located in Bozeman. The program requires 2 semesters and 33 to cover the cost of their travel for development purposes. The Foundation will provide assistance. A clarification was requested that this is "certificate program". The vote was unanimous in favor of the motion

  3. Monday Tuesday Wednesday Thursday Friday Saturday Sunday

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment SurfacesResource ProgramModification andinterface of water.OrganicNov 4 5 6 7 8 9 10

  4. Monday Tuesday Wednesday Thursday Friday Saturday Sunday

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment SurfacesResource ProgramModification andinterface of water.OrganicNov 4 5 6 7 8 9

  5. Monday Tuesday Wednesday Thursday Friday Saturday Sunday

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment SurfacesResource ProgramModification andinterface of water.OrganicNov 4 5 6 7 8

  6. Sustainable Nanomaterials Workshop - Tuesday June 26, 2012

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |Energy Usage »of Energy Strain Rate4SuperhardSuspect andCoaches Aim IndustrySustainable

  7. Major NERSC Maintenance Tuesday November 11

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and InterfacesAdministration -Lowellfor 2013 |Spherical Torus

  8. Sandia National Laboratories: Tuesday September 9, 2014

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -theErikGroundbreakingStandardsTCESJBEI ResearchersTrough Systems CSP Industry

  9. Tuesday, August 14, 2007 | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up from theDepartment of EnergyTheDepartment of Energy and MilitaryTrust

  10. Tuesday, December 04, 2007 | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up from theDepartment of EnergyTheDepartment of Energy and MilitaryTrustDecember

  11. Tuesday, February 12, 2008 | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up from theDepartment of EnergyTheDepartment of Energy and

  12. Tuesday, January 08, 2008 | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up from theDepartment of EnergyTheDepartment of Energy andJanuary 08, 2008

  13. Tuesday, September 11, 2007 | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up from theDepartment of EnergyTheDepartment of Energy andJanuary 08,

  14. UCCE Pollinator Workshop Tuesday, February 21, 2012

    E-Print Network [OSTI]

    Ferrara, Katherine W.

    Long, Farm Advisor, UCCE Yolo County 9:10 ­ 9:35am Multiple Stresses are Hard on Honey Bees: Dr. Eric by the University of California Cooperative Extension Service (UCCE) and the Yolo County Resource Conservation

  15. COSMIC-RAY TRANSPORT AND ANISOTROPIES

    SciTech Connect (OSTI)

    Biermann, Peter L. [MPI for Radioastronomy, Auf dem Huegel 69, D-53121 Bonn (Germany); Becker Tjus, Julia; Mandelartz, Matthias [Ruhr-Universitaet Bochum, Fakultaet fuer Physik and Astronomie, Theoretische Physik I, D-44780 Bochum (Germany); Seo, Eun-Suk [Department of Physics, University of Maryland, College Park, MD 20742 (United States)

    2013-05-10T23:59:59.000Z

    We show that the large-scale cosmic-ray anisotropy at {approx}10 TeV can be explained by a modified Compton-Getting effect in the magnetized flow field of old supernova remnants. Cosmic rays arrive isotropically to the flow field and are then carried along with the flow to produce a large-scale anisotropy in the arrival direction. This approach suggests an optimum energy scale for detecting the anisotropy. Two key assumptions are that propagation is based on turbulence following a Kolmogorov law and that cosmic-ray interactions are dominated by transport via cosmic-ray-excited magnetic irregularities through the stellar wind of an exploding star and its shock shell. A prediction is that the amplitude is smaller at lower energies due to incomplete sampling of the velocity field and also smaller at larger energies due to smearing.

  16. IsoRay Medical William A. Cavanagh

    E-Print Network [OSTI]

    2011 #12;IsoRay Medical AMEX: ISR Founded: 1998 Richland, Washington Employees: 35 Market Cap (3 complex. The production facility is completely independent with it's own HVAC and Emergency Power Systems

  17. Invariance Violation Extends the Cosmic Ray Horizon?

    E-Print Network [OSTI]

    Kifune, T

    1999-01-01T23:59:59.000Z

    We postulate in the present paper that the energy-momentum relation is modified for very high energy particles to violate Lorentz invariance and the speed of photon is changed from the light velocity c. The violation effect is amplified, in a sensitive way to detection, through the modified kinematical constraints on the conservation of energy and momentum, in the absorption process of gamma-rays colliding against photons of longer wavelengths and converting into an electron-positron pair. For gamma-rays of energies higher than 10 TeV, the minimum energy of the soft photons for the reaction and then the absorption mean free path of gamma-rays are altered by orders of magnitude from the ones conventionally estimated. Consideration is similarly applied to high energy cosmic ray protons. The consequences may require the standard assumptions on the maximum distance that very high energy radiation can travel from to be revised.

  18. Invariance Violation Extends the Cosmic Ray Horizon ?

    E-Print Network [OSTI]

    T. Kifune

    1999-04-13T23:59:59.000Z

    We postulate in the present paper that the energy-momentum relation is modified for very high energy particles to violate Lorentz invariance and the speed of photon is changed from the light velocity c. The violation effect is amplified, in a sensitive way to detection, through the modified kinematical constraints on the conservation of energy and momentum, in the absorption process of gamma-rays colliding against photons of longer wavelengths and converting into an electron-positron pair. For gamma-rays of energies higher than 10 TeV, the minimum energy of the soft photons for the reaction and then the absorption mean free path of gamma-rays are altered by orders of magnitude from the ones conventionally estimated. Consideration is similarly applied to high energy cosmic ray protons. The consequences may require the standard assumptions on the maximum distance that very high energy radiation can travel from to be revised.

  19. Mining Gamma-Ray Burst Data

    E-Print Network [OSTI]

    Jon Hakkila; Richard J. Roiger; David J. Haglin; Robert S. Mallozzi; Geoffrey N. Pendleton; Charles A. Meegan

    2000-11-30T23:59:59.000Z

    Gamma-ray bursts provide what is probably one of the messiest of all astrophysical data sets. Burst class properties are indistinct, as overlapping characteristics of individual bursts are convolved with effects of instrumental and sampling biases. Despite these complexities, data mining techniques have allowed new insights to be made about gamma-ray burst data. We demonstrate how data mining techniques have simultaneously allowed us to learn about gamma-ray burst detectors and data collection, cosmological effects in burst data, and properties of burst subclasses. We discuss the exciting future of this field, and the web-based tool we are developing (with support from the NASA AISR Program). We invite others to join us in AI-guided gamma-ray burst classification (http://grb.mnsu.edu/grb/).

  20. PUBLISHED VERSION Gamma ray spectrometer for ITER

    E-Print Network [OSTI]

    Ray Scintillation Spectrometer Rev. Sci. Instrum. 24, 1096 (1953); 10.1063/1.1770609 An Automatic Recording Gamma for the spectrometer is presented. Keywords: tokamak, DT plasma, alpha- particles, diagnostics, gamma- spectrometry

  1. Small Angle X-Ray Scattering Detector

    DOE Patents [OSTI]

    Hessler, Jan P.

    2004-06-15T23:59:59.000Z

    A detector for time-resolved small-angle x-ray scattering includes a nearly constant diameter, evacuated linear tube having an end plate detector with a first fluorescent screen and concentric rings of first fiber optic bundles for low angle scattering detection and an annular detector having a second fluorescent screen and second fiber optic bundles concentrically disposed about the tube for higher angle scattering detection. With the scattering source, i.e., the specimen under investigation, located outside of the evacuated tube on the tube's longitudinal axis, scattered x-rays are detected by the fiber optic bundles, to each of which is coupled a respective photodetector, to provide a measurement resolution, i.e., dq/q, where q is the momentum transferred from an incident x-ray to an x-ray scattering specimen, of 2% over two (2) orders of magnitude in reciprocal space, i.e., qmax/qmin approx=lO0.

  2. The beginning of cosmic ray astronomy

    E-Print Network [OSTI]

    Todor Stanev

    2008-08-08T23:59:59.000Z

    We discuss the anisotropic arrival directions of the ultra high energy cosmic rays detected by Auger which I consider one of the biggest discoverie in astrophysics during the last year.

  3. Gravitational waves and short gamma ray bursts.

    E-Print Network [OSTI]

    Predoi, Valeriu

    2012-01-01T23:59:59.000Z

    ??Short hard gamma-ray bursts (GRB) are believed to be produced by compact binary coalescences (CBC) { either double neutron stars or neutron star{black hole binaries. (more)

  4. X-ray grid-detector apparatus

    DOE Patents [OSTI]

    Boone, John M. (Folsom, CA); Lane, Stephen M. (Oakland, CA)

    1998-01-27T23:59:59.000Z

    A hybrid grid-detector apparatus for x-ray systems wherein a microchannel plate structure has an air-interspaced grid portion and a phosphor/optical fluid-filled grid portion. The grids are defined by multiple adjacent channels separated by lead-glass septa. X-rays entering the air-interspaced grid portion at an angle of impingement upon the septa are attenuated, while non-impinging x-rays pass through to the phosphor/fluid filled portion. X-ray energy is converted to luminescent energy in the phosphor/fluid filled portion and the resultant beams of light are directed out of the phosphor/optical fluid filled portion to an imaging device.

  5. X-ray source for mammography

    DOE Patents [OSTI]

    Logan, Clinton M. (Pleasanton, CA)

    1994-01-01T23:59:59.000Z

    An x-ray source utilizing anode material which shifts the output spectrum to higher energy and thereby obtains higher penetrating ability for screening mammography application, than the currently utilized anode material. The currently used anode material (molybdenum) produces an energy x-ray spectrum of 17.5/19.6 keV, which using the anode material of this invention (e.g. silver, rhodium, and tungsten) the x-ray spectrum would be in the 20-35 keV region. Thus, the anode material of this invention provides for imaging of breasts with higher than average x-ray opacity without increase of the radiation dose, and thus reduces the risk of induced breast cancer due to the radiation dose administered for mammograms.

  6. Gravitational waves and gamma-ray bursts

    E-Print Network [OSTI]

    Alessandra Corsi; for the LIGO Scientific Collaboration; for the Virgo Collaboration

    2012-05-11T23:59:59.000Z

    Gamma-Ray Bursts are likely associated with a catastrophic energy release in stellar mass objects. Electromagnetic observations provide important, but indirect information on the progenitor. On the other hand, gravitational waves emitted from the central source, carry direct information on its nature. In this context, I give an overview of the multi-messenger study of gamma-ray bursts that can be carried out by using electromagnetic and gravitational wave observations. I also underline the importance of joint electromagnetic and gravitational wave searches, in the absence of a gamma-ray trigger. Finally, I discuss how multi-messenger observations may probe alternative gamma-ray burst progenitor models, such as the magnetar scenario.

  7. X-ray induced optical reflectivity

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Durbin, Stephen M.

    2012-01-01T23:59:59.000Z

    The change in optical reflectivity induced by intense x-ray pulses can now be used to study ultrafast many body responses in solids in the femtosecond time domain. X-ray absorption creates photoelectrons and core level holes subsequently filled by Auger or fluorescence processes, and these excitations ultimately add conduction and valence band carriers that perturb optical reflectivity.Optical absorption associated with band filling and band gap narrowing is shown to explain the basic features found in recent measurements on an insulator (silicon nitride, Si3N4), a semiconductor(gallium arsenide,GaAs), and a metal (gold,Au), obtained with ?100 fs x-ray pulses at 500-2000 eV and probed with 800 nm laser pulses. In particular GaAs exhibits an abrupt drop in reflectivity, persisting only for a time comparable to the x-ray excitation pulse duration, consistent with prompt band gap narrowing.

  8. Can gamma-ray bursts constrain quintessence?

    E-Print Network [OSTI]

    T. Di Girolamo; R. Catena; M. Vietri; G. Di Sciascio

    2005-04-27T23:59:59.000Z

    Using the narrow clustering of the geometrically corrected gamma-ray energies released by gamma-ray bursts, we investigate the possibility of using these sources as standard candles to probe cosmological parameters such as the matter density Omega_m and the cosmological constant energy density Omega_Lambda. By simulating different samples of gamma-ray bursts, we find that Omega_m can be determined with accuracy ~7% with data from 300 sources. We also show that, if Omega = 1 is due to a quintessence field, some of the models proposed in the literature may be discriminated from a Universe with cosmological constant, by a similar-sized sample of gamma-ray bursts.

  9. Diffuse gamma-rays from galactic halos

    E-Print Network [OSTI]

    M. Pohl

    1996-03-12T23:59:59.000Z

    Here we review our current knowledge on diffuse gamma-rays from galactic halos. Estimates of the relative contribution of the various emission processes at low and high latitudes are compared to the data over 6 decades in energy. The observed spectral shape differs from what was expected, especially at ver low and very high energies. In the latter case, above 1 GeV, the sky emission related to gas exceeds the expected pi^0 decay spectrum. At energies below 1 MeV the relatively high gamma-ray intensity indicates at high density of nearly relativistic electrons which would have a strong influence on the energy and ionisation balance of the interstellar medium. Given the EGRET results for the Magellanic Clouds the gamma-ray emissivity in the outer halo is probably small, so that a substantial amount of baryonic dark matter may be hidden at 20-50 kpc radius without inducing observable gamma-ray emission.

  10. Columbia University X-Ray Measurements

    E-Print Network [OSTI]

    Columbia University X-Ray Measurements of the Levitated Dipole Experiment J. L. Ellsworth, J. Kesner MIT Plasma Science and Fusion Center D.T. Garnier, A.K. Hansen, M.E. Mauel Columbia University

  11. X-Ray Nanoimaging: Instruments and Methods

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    X-Ray Nanoimaging: Instruments and Methods To be held as part of SPIE. http:spie.orgOP318 August 28-29, 2013; San Diego, California, USA...

  12. X-ray source for mammography

    DOE Patents [OSTI]

    Logan, C.M.

    1994-12-20T23:59:59.000Z

    An x-ray source is described utilizing anode material which shifts the output spectrum to higher energy and thereby obtains higher penetrating ability for screening mammography application, than the currently utilized anode material. The currently used anode material (molybdenum) produces an energy x-ray spectrum of 17.5/19.6 keV, which using the anode material of this invention (e.g. silver, rhodium, and tungsten) the x-ray spectrum would be in the 20-35 keV region. Thus, the anode material of this invention provides for imaging of breasts with higher than average x-ray opacity without increase of the radiation dose, and thus reduces the risk of induced breast cancer due to the radiation dose administered for mammograms. 6 figures.

  13. The highest-energy cosmic rays

    E-Print Network [OSTI]

    James W. Cronin

    2004-02-20T23:59:59.000Z

    This paper begins with a pedagogical discussion of the propagation of cosmic rays and the showers produced when a cosmic ray primary hits the upper atmosphere. The paper focusses cosmic rays, with energy > 10^19 eV. Emphasis is placed on the shower properties that are relevant to the detection of cosmic rays by surface arrays and fluorescence telescopes. The two major experiments, AGASA and HiRes are described in some detail. Then the experimental results are reviewed. It is no surprise that more data will be needed. But it is also true that improved analysis and further data from HiRes can make significant improvements in the experimental situation.

  14. Shallow Decay of Early X-ray Afterglows from Inhomogeneous Gamma-Ray Burst Jets

    E-Print Network [OSTI]

    Toma, K; Yamazaki, R; Nakamura, T; Toma, Kenji; Ioka, Kunihito; Yamazaki, Ryo; Nakamura, Takashi

    2006-01-01T23:59:59.000Z

    Almost all the X-ray afterglows of gamma-ray bursts (GRBs) observed by the Swift satellite have a shallow decay phase in the first thousands of seconds. We show that in an inhomogeneous jet (multiple-subjet or patchy-shell) model the superposition of the afterglows of off-axis subjets (patchy shells) can have the shallow decay phase. The necessary condition for obtaining the shallow decay phase is that gamma-ray bright subjets (patchy shells) should have gamma-ray efficiency higher than previously estimated, and should be surrounded by gamma-ray dim subjets (patchy shells) with low gamma-ray efficiency. Our model predicts that events with dim prompt emission have the conventional afterglow light curve without the shallow decay phase like GRB 050416A.

  15. Simultaneous Planck, Swift, and Fermi observations of X-ray and gamma-ray selected blazars

    E-Print Network [OSTI]

    Giommi, P; Lahteenmaki, A; Thompson, D J; Capalbi, M; Cutini, S; Gasparrini, D; Gonzalez-Nuevo, J; Leon-Tavares, J; Lopez-Caniego, M; Mazziotta, M N; Monte, C; Perri, M; Raino, S; Tosti, G; Tramacere, A; Verrecchia, F; Aller, H D; Aller, M F; Angelakis, E; Bastieri, D; Berdyugin, A; Bonaldi, A; Bonavera, L; Burigana, C; Burrows, D N; Buson, S; Cavazzuti, E; Chincarini, G; Colafrancesco, S; Costamante, L; Cuttaia, F; D'Ammando, F; de Zotti, G; Frailis, M; Fuhrmann, L; Galeotta, S; Gargano, F; Gehrels, N; Giglietto, N; Giordano, F; Giroletti, M; Keihanen, E; King, O; Krichbaum, T P; Lasenby, A; Lavonen, N; Lawrence, C R; Leto, C; Lindfors, E; Mandolesi, N; Massardi, M; Max-Moerbeck, W; Michelson, P F; Mingaliev, M; Natoli, P; Nestoras, I; Nieppola, E; Nilsson, K; Partridge, B; Pavlidou, V; Pearson, T J; Procopio, P; Rachen, J P; Readhead, A; Reeves, R; Reimer, A; Reinthal, R; Ricciardi, S; Richards, J; Riquelme, D; Saarinen, J; Sajina, A; Sandri, M; Savolainen, P; Sievers, A; Sillanpaa, A; Sotnikova, Y; Stevenson, M; Tagliaferri, G; Takalo, L; Tammi, J; Tavagnacco, D; Terenzi, L; Toffolatti, L; Tornikoski, M; Trigilio, C; Turunen, M; Umana, G; Ungerechts, H; Villa, F; Wu, J; Zacchei, A; Zensus, J A; Zhou, X

    2011-01-01T23:59:59.000Z

    We present simultaneous Planck, Swift, Fermi, and ground-based data for 105 blazars belonging to three samples with flux limits in the soft X-ray, hard X-ray, and gamma-ray bands. Our unique data set has allowed us to demonstrate that the selection method strongly influences the results, producing biases that cannot be ignored. Almost all the BL Lac objects have been detected by Fermi-LAT, whereas ~40% of the flat-spectrum radio quasars (FSRQs) in the radio, soft X-ray, and hard X-ray selected samples are still below the gamma-ray detection limit even after integrating 27 months of Fermi-LAT data. The radio to sub-mm spectral slope of blazars is quite flat up to ~70GHz, above which it steepens to ~-0.65. BL Lacs have significantly flatter spectra than FSRQs at higher frequencies. The distribution of the rest-frame synchrotron peak frequency (\

  16. Indus-2 X-ray lithography beamline for X-ray optics and material science applications

    SciTech Connect (OSTI)

    Dhamgaye, V. P., E-mail: vishal@rrcat.gov.in; Lodha, G. S., E-mail: vishal@rrcat.gov.in [Indus Synchrotrons Utilisation Division, Raja Ramanna Centre for Advanced Technology, Indore-452013 (India)

    2014-04-24T23:59:59.000Z

    X-ray lithography is an ideal technique by which high aspect ratio and high spatial resolution micro/nano structures are fabricated using X-rays from synchrotron radiation source. The technique has been used for fabricating optics (X-ray, visible and infrared), sensors and actuators, fluidics and photonics. A beamline for X-ray lithography is operational on Indus-2. The beamline offers wide lithographic window from 1-40keV photon energy and wide beam for producing microstructures in polymers upto size ?100mm 100mm. X-ray exposures are possible in air, vacuum and He gas environment. The air based exposures enables the X-ray irradiation of resist for lithography and also irradiation of biological and liquid samples.

  17. Linearly polarized X-ray flares following short gamma-ray bursts

    E-Print Network [OSTI]

    Y. Z. Fan; Bing Zhang; Daniel Proga

    2005-11-16T23:59:59.000Z

    Soft X-ray flares were detected to follow the short-duration gamma-ray burst GRB 050724. The temporal properties of the flares suggest that they are likely due to the late time activity of the central engine. We argue that if short GRBs are generated through compact star mergers, as is supported by the recent observations, the jet powering the late X-ray flares must be launched via magnetic processes rather than via neutrino-antineutrino annihilations. As a result, the X-ray flares following short GRBs are expected to be linearly polarized. The argument may also apply to the X-ray flares following long GRBs. Future observations with the upcoming X-ray polarimeters will test this prediction.

  18. X-ray views of neutron star low-mass X-ray binaries

    E-Print Network [OSTI]

    Sudip Bhattacharyya

    2010-02-24T23:59:59.000Z

    A neutron star low-mass X-ray binary is a binary stellar system with a neutron star and a low-mass companion star rotating around each other. In this system the neutron star accretes mass from the companion, and as this matter falls into the deep potential well of the neutron star, the gravitational potential energy is released primarily in the X-ray wavelengths. Such a source was first discovered in X-rays in 1962, and this discovery formally gave birth to the "X-ray astronomy". In the subsequent decades, our knowledge of these sources has increased enormously by the observations with several X-ray space missions. Here we give a brief overview of our current understanding of the X-ray observational aspects of these systems.

  19. Principles of X-ray Navigation

    SciTech Connect (OSTI)

    Hanson, John Eric; /SLAC

    2006-03-17T23:59:59.000Z

    X-ray navigation is a new concept in satellite navigation in which orientation, position and time are measured by observing stellar emissions in x-ray wavelengths. X-ray navigation offers the opportunity for a single instrument to be used to measure these parameters autonomously. Furthermore, this concept is not limited to missions in close proximity to the earth. X-ray navigation can be used on a variety of missions from satellites in low earth orbit to spacecraft on interplanetary missions. In 1997 the Unconventional Stellar Aspect Experiment (USA) will be launched as part of the Advanced Research and Global Observation Satellite (ARGOS). USA will provide the first platform for real-time experimentation in the field of x-ray navigation and also serves as an excellent case study for the design and manufacturing of space qualified systems in small, autonomous groups. Current techniques for determining the orientation of a satellite rely on observations of the earth, sun and stars in infrared, visible or ultraviolet wavelengths. It is possible to use x-ray imaging devices to provide arcsecond level measurement of attitude based on star patterns in the x-ray sky. This technique is explored with a simple simulation. Collimated x-ray detectors can be used on spinning satellites to provide a cheap and reliable measure of orientation. This is demonstrated using observations of the Crab Pulsar taken by the high Energy Astronomy Observatory (HEAO-1) in 1977. A single instrument concept is shown to be effective, but dependent on an a priori estimate of the guide star intensity and thus susceptible to errors in that estimate. A star scanner based on a differential measurement from two x-ray detectors eliminates the need for an a priori estimate of the guide star intensity. A first order model and a second order model of the two star scanner concepts are considered. Many of the stars that emit in the x-ray regime are also x-ray pulsars with frequency stability approaching a part in 10{sup 9}. By observing these pulsations, a satellite can keep accurate time autonomously. They have demonstrated the acquisition and tracking of the Crab nebula pulsar by simulating the operation of a phase-locked loop.

  20. Gamma Ray Bursts from Ordinary Cosmic Strings

    E-Print Network [OSTI]

    R. H. Brandenberger; A. T. Sornborger; M. Trodden

    1993-02-12T23:59:59.000Z

    We give an upper estimate for the number of gamma ray bursts from ordinary (non-superconducting) cosmic strings expected to be observed at terrestrial detectors. Assuming that cusp annihilation is the mechanism responsible for the bursts we consider strings arising at a GUT phase transition and compare our estimate with the recent BATSE results. Further we give a lower limit for the effective area of future detectors designed to detect the cosmic string induced flux of gamma ray bursts.

  1. The calculation of ionospheric ray paths

    E-Print Network [OSTI]

    Koehler, Buford Ray

    1967-01-01T23:59:59.000Z

    Parabolic ionospheric layer of electrons, altitude versus electron density Page 1- 2 Sample ray paths with constant angle of propagation and increasing frequency, parabolic ionosphere of electrons assumed, earth's magnetic field neglected 1- 3 Sample... ray paths with constant frequency and variable angle of propagation and range, parabolic ionosphere of electrons assumed, earth's magnetic field neglected 2- 1 The vertical and lateral deviations of a radio wave propagated in a plane ionosphere...

  2. X-Ray Observations of Radio Galaxies

    E-Print Network [OSTI]

    D. E. Harris

    1998-04-20T23:59:59.000Z

    We review some of the ways that X-ray observations provide unique information on radio galaxies. Thermal bremsstrahlung X-ray emission provides detailed data on ambient densities and temperatures. These parameters in turn can be used for pressure balance calculations and can demonstrate how the ambient gas affects radio source structure. Additionally, many signatures of the interaction of radio jets and lobes with the hot gas are found in high resolution X-ray maps. Non-thermal X-ray emission from knots and hotspots of radio jets can give us constraints on the relativistic electron population for energies greater that that normally sampled in the radio (in the case of synchrotron emission) or can give us an independent estimate of the average magnetic field strength (if inverse Compton emission is the origin of the X-rays). From recent ROSAT HRI observations of 3C 390.3 and 3C 120, we show evidence that X-ray emission from knots and hotspots appears to be associated with regions of large gradients in the radio surface brightness; i.e. at the location of powerful shocks.

  3. Compton backscattered collimated x-ray source

    DOE Patents [OSTI]

    Ruth, R.D.; Huang, Z.

    1998-10-20T23:59:59.000Z

    A high-intensity, inexpensive and collimated x-ray source is disclosed for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications. 4 figs.

  4. Compton backscattered collmated X-ray source

    DOE Patents [OSTI]

    Ruth, Ronald D. (Woodside, CA); Huang, Zhirong (Stanford, CA)

    2000-01-01T23:59:59.000Z

    A high-intensity, inexpensive and collimated x-ray source for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications.

  5. Compton backscattered collimated x-ray source

    DOE Patents [OSTI]

    Ruth, Ronald D. (Woodside, CA); Huang, Zhirong (Stanford, CA)

    1998-01-01T23:59:59.000Z

    A high-intensity, inexpensive and collimated x-ray source for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications.

  6. Delayed Nickel Decay in Gamma Ray Bursts

    E-Print Network [OSTI]

    G. C. McLaughlin; R. A. M. J. Wijers

    2002-05-19T23:59:59.000Z

    Recently observed emission lines in the X-ray afterglow of gamma ray bursts suggest that iron group elements are either produced in the gamma ray burst, or are present nearby. If this material is the product of a thermonuclear burn, then such material would be expected to be rich in Nickel-56. If the nickel remains partially ionized, this prevents the electron capture reaction normally associated with the decay of Nickel-56, dramatically increasing the decay timescale. Here we examine the consequences of rapid ejection of a fraction of a solar mass of iron group material from the center of a collapsar/hypernova. The exact rate of decay then depends on the details of the ionization and therefore the ejection process. Future observations of iron, nickel and cobalt lines can be used to diagnose the origin of these elements and to better understand the astrophysical site of gamma ray bursts. In this model, the X-ray lines of these iron-group elements could be detected in suspected hypernovae that did not produce an observable gamma ray burst due to beaming.

  7. Transient x-ray diffraction and its application to materials science and x-ray optics

    SciTech Connect (OSTI)

    Hauer, A.A.; Kopp, R.; Cobble, J.; Kyrala, G.; Springer, R. [and others

    1997-12-01T23:59:59.000Z

    Time resolved x-ray diffraction and scattering have been applied to the measurement of a wide variety of physical phenomena from chemical reactions to shock wave physics. Interest in this method has heightened in recent years with the advent of versatile, high power, pulsed x-ray sources utilizing laser plasmas, electron beams and other methods. In this article, we will describe some of the fundamentals involved in time resolved x-ray diffraction, review some of the history of its development, and describe some recent progress in the field. In this article we will emphasize the use of laser-plasmas as the x-ray source for transient diffraction.

  8. High energy cosmic-rays from gamma-ray burst sources: A stronger case

    E-Print Network [OSTI]

    E. Waxman

    2004-01-20T23:59:59.000Z

    The suggested association between the sources of gamma-ray bursts (GRB's) and the sources of ultra-high energy cosmic rays (UHECR's) is based on two arguments: (i) The average energy generation rate of UHECR's is similar to the gamma-ray generation rate of GRB's, and (ii) The constraints that UHECR sources must satisfy to allow proton acceleration to >10^{20} eV are similar to those inferred for GRB sources from gamma-ray observations. We show that recent GRB and UHECR observations strengthen both arguments, and hence strengthen the suggested association.

  9. Lag-luminosity relation in gamma-ray burst X-ray flares

    SciTech Connect (OSTI)

    Margutti, R.

    2010-10-15T23:59:59.000Z

    In strict analogy to prompt pulses, X-ray flares observed by Swift-XRT in long Gamma-Ray Bursts define a lag-luminosity relation: L{sub p,iso}{sup 0.3-10} k{sup eV} {infinity}t{sub lag}{sup -0.95{+-}0.23}. The lag-luminosity is proven to be a fundamental law extending {approx}5 decades in time and {approx}5 in energy. This is direct evidence that GRB X-ray flares and prompt gamma-ray pulses are produced by the same mechanism.

  10. Are gamma-ray bursts the sources of ultra-high energy cosmic rays?

    E-Print Network [OSTI]

    Philipp Baerwald; Mauricio Bustamante; Walter Winter

    2014-07-07T23:59:59.000Z

    We reconsider the possibility that gamma-ray bursts (GRBs) are the sources of the ultra-high energy cosmic rays (UHECRs) within the internal shock model, assuming a pure proton composition of the UHECRs. For the first time, we combine the information from gamma-rays, cosmic rays, prompt neutrinos, and cosmogenic neutrinos quantitatively in a joint cosmic ray production and propagation model, and we show that the information on the cosmic energy budget can be obtained as a consequence. In addition to the neutron model, we consider alternative scenarios for the cosmic ray escape from the GRBs, i.e., that cosmic rays can leak from the sources. We find that the dip model, which describes the ankle in UHECR observations by the pair production dip, is strongly disfavored in combination with the internal shock model because a) unrealistically high baryonic loadings (energy in protons versus energy in electrons/gamma-rays) are needed for the individual GRBs and b) the prompt neutrino flux easily overshoots the corresponding neutrino bound. On the other hand, GRBs may account for the UHECRs in the ankle transition model if cosmic rays leak out from the source at the highest energies. In that case, we demonstrate that future neutrino observations can efficiently test most of the parameter space -- unless the baryonic loading is much larger than previously anticipated.

  11. A common stochastic process rules gamma-ray burst prompt emission and X-ray flares

    E-Print Network [OSTI]

    Guidorzi, C; Frontera, F; Margutti, R; Baldeschi, A; Amati, L

    2015-01-01T23:59:59.000Z

    Prompt gamma-ray and early X-ray afterglow emission in gamma-ray bursts (GRBs) are characterized by a bursty behavior and are often interspersed with long quiescent times. There is compelling evidence that X-ray flares are linked to prompt gamma-rays. However, the physical mechanism that leads to the complex temporal distribution of gamma-ray pulses and X-ray flares is not understood. Here we show that the waiting time distribution (WTD) of pulses and flares exhibits a power-law tail extending over 4 decades with index ~2 and can be the manifestation of a common time-dependent Poisson process. This result is robust and is obtained on different catalogs. Surprisingly, GRBs with many (>=8) gamma-ray pulses are very unlikely to be accompanied by X-ray flares after the end of the prompt emission (3.1 sigma Gaussian confidence). These results are consistent with a simple interpretation: an hyperaccreting disk breaks up into one or a few groups of fragments, each of which is independently accreted with the same pro...

  12. Reflection soft X-ray microscope and method

    DOE Patents [OSTI]

    Suckewer, Szymon (Princeton, NJ); Skinner, Charles H. (Lawrenceville, NJ); Rosser, Roy (Princeton, NJ)

    1993-01-01T23:59:59.000Z

    A reflection soft X-ray microscope is provided by generating soft X-ray beams, condensing the X-ray beams to strike a surface of an object at a predetermined angle, and focusing the X-ray beams reflected from the surface onto a detector, for recording an image of the surface or near surface features of the object under observation.

  13. Differential phase contrast X-ray imaging system and components

    DOE Patents [OSTI]

    Stutman, Daniel; Finkenthal, Michael

    2014-07-01T23:59:59.000Z

    A differential phase contrast X-ray imaging system includes an X-ray illumination system, a beam splitter arranged in an optical path of the X-ray illumination system, and a detection system arranged in an optical path to detect X-rays after passing through the beam splitter.

  14. X-ray focal spot locating apparatus and method

    DOE Patents [OSTI]

    Gilbert, Hubert W. (Cedar Crest, NM)

    1985-07-30T23:59:59.000Z

    An X-ray beam finder for locating a focal spot of an X-ray tube includes a mass of X-ray opaque material having first and second axially-aligned, parallel-opposed faces connected by a plurality of substantially identical parallel holes perpendicular to the faces and a film holder for holding X-ray sensitive film tightly against one face while the other face is placed in contact with the window of an X-ray head.

  15. Constraints on the Cosmic Rays in the Small Magellanic Cloud

    E-Print Network [OSTI]

    Arnon Dar; Ari Laor; Abraham Loeb

    1993-02-25T23:59:59.000Z

    We show that recent $\\gamma$-ray observations of the Small Magellanic Cloud with EGRET rule out a universal cosmic ray flux only at energies below $\\approx 10$ GeV, while the observed diffuse X-ray and $\\gamma$-ray background radiations have already ruled out, by more than three orders of magnitude, a universal extragalactic cosmic ray flux identical to that observed in the local solar neighborhood at energies below $10^6$ GeV.

  16. X-Ray Observations of Unidentified H.E.S.S. Gamma-Ray Sources

    SciTech Connect (OSTI)

    Funk, S.; /SLAC

    2007-10-10T23:59:59.000Z

    In a survey of the inner part of the Galaxy, performed with the H.E.S.S. Instrument (High energy stereoscopic system) in 2004 and 2005, a large number of new unidentified very high energy (VHE) {gamma}-ray sources above an energy of 100 GeV was discovered. Often the {gamma}-ray spectra in these sources reach energies of up to {approx} 10 TeV. These are the highest energy particles ever attributed to single astrophysical objects. While a few of these sources can be identified at other wavebands, most of these sources remain unidentified so far. A positive identification of these new g-ray sources with a counterpart object at other wavebands requires (a) a positional coincidence between the two sources,( b) a viable {gamma}-ray emission mechanism and (c) a consistent multiwavelength behavior of the two sources. X-ray observations with satellites such as XMM-Newton, Chandra or Suzaku provide one of the best channels to studying these enigmatic {gamma}-ray sources at other wavebands, since they combine high angular resolution and sensitivity with the ability to access non-thermal electrons through their synchrotron emission. We therefore have started a dedicated program to investigate VHE {gamma}-ray sources with high-sensitivity X-ray instruments.

  17. High spatial resolution X-ray and gamma ray imaging system using diffraction crystals

    DOE Patents [OSTI]

    Smither, Robert K. (Hinsdale, IL)

    2011-05-17T23:59:59.000Z

    A method and a device for high spatial resolution imaging of a plurality of sources of x-ray and gamma-ray radiation are provided. The device comprises a plurality of arrays, with each array comprising a plurality of elements comprising a first collimator, a diffracting crystal, a second collimator, and a detector.

  18. X-RAY SPECTROMETRY X-Ray Spectrom. 2007; 36: 336342

    E-Print Network [OSTI]

    Limburg, Karin E.

    , Chicago, IL 60637, USA 3 Cornell High Energy Synchrotron Source and School of Applied and EngineeringX-RAY SPECTROMETRY X-Ray Spectrom. 2007; 36: 336­342 Published online in Wiley InterScience (www to establish a breakthrough in high-resolution, simultaneous area mapping of multiple trace elements

  19. COSMIC-RAY AND X-RAY HEATING OF INTERSTELLAR CLOUDS AND PROTOPLANETARY DISKS

    SciTech Connect (OSTI)

    Glassgold, Alfred E. [Astronomy Department, University of California, Berkeley, CA 94720-3411 (United States); Galli, Daniele [INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 (Italy); Padovani, Marco, E-mail: aglassgold@berkeley.edu, E-mail: galli@arcetri.astro.it, E-mail: marco.padovani@lra.ens.fr [Laboratoire de Radioastronomie Millimetrique, UMR 8112 du CNRS, Ecole Normale Superieure et Observatoire de Paris, 24 rue Lhomond, F-75231 Paris Cedex 05 (France)

    2012-09-10T23:59:59.000Z

    Cosmic-ray and X-ray heating are derived from the electron energy-loss calculations of Dalgarno, Yan, and Liu for hydrogen-helium gas mixtures. These authors treated the heating from elastic scattering and collisional de-excitation of rotationally excited hydrogen molecules. Here we consider the heating that can arise from all ionization and excitation processes, with particular emphasis on the reactions of cosmic-ray and X-ray generated ions with the heavy neutral species, which we refer to as chemical heating. In molecular regions, chemical heating dominates and can account for 50% of the energy expended in the creation of an ion pair. The heating per ion pair ranges in the limit of negligible electron fraction from {approx}4.3 eV for diffuse atomic gas to {approx}13 eV for the moderately dense regions of molecular clouds and to {approx}18 eV for the very dense regions of protoplanetary disks. An important general conclusion of this study is that cosmic-ray and X-ray heating depends on the physical properties of the medium, i.e., on the molecular and electron fractions, the total density of hydrogen nuclei, and, to a lesser extent, on the temperature. It is also noted that chemical heating, the dominant process for cosmic-ray and X-ray heating, plays a role in UV irradiated molecular gas.

  20. In Operando X-ray Diffraction and Transmission X-ray Microscopy of Lithium Sulfur Batteries

    E-Print Network [OSTI]

    Cui, Yi

    In Operando X-ray Diffraction and Transmission X-ray Microscopy of Lithium Sulfur Batteries Johanna Information ABSTRACT: Rechargeable lithium-sulfur (Li-S) batteries hold great potential for high of these batteries for commercial use. The two primary obstacles are the solubility of long chain lithium

  1. X-Ray Data from the X-Ray Data Booklet Online

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Thompson, Albert C.; Attwood, David T.; Gullikson, Eric M.; Howells, Malcolm R.; Kortright, Jeffrey B.; Robinson, Arthur L.; Underwood, James H.; Kim, Kwang-Je; Kirz, Janos; Lindau, Ingolf; Pianetta, Piero; Winick, Herman; Williams, Gwyn P.; Scofield, James H.

    The original X-Ray Data Booklet, published in 1985, became a classic reference source. The online version has been significantly revised and updated to reflect today's science. Hundreds of pages of authoritative data provide the x-ray properties of elements, information on synchrotron radiation, scattering processes, optics and detectors, and other related calculations, formulas, and data tables.

  2. Acceleration of cosmic rays and gamma-ray emission from supernova remnant/molecular cloud associations

    E-Print Network [OSTI]

    Gabici, S; Morlino, G; Nava, L

    2015-01-01T23:59:59.000Z

    The gamma-ray observations of molecular clouds associated with supernova remnants are considered one of the most promising ways to search for a solution of the problem of cosmic ray origin. Here we briefly review the status of the field, with particular emphasis on the theoretical and phenomenological aspects of the problem.

  3. Predicted X-ray backgrounds for the International X-ray Observatory

    E-Print Network [OSTI]

    Bautz, Marshall W.

    The background that will be observed by IXO's X-ray detectors naturally separates into two components: (1) a Cosmic X-ray Background (CXB), primarily due to unresolved point sources at high energies (E>2 keV), along with ...

  4. Oscillations During Thermonuclear X-ray Bursts

    E-Print Network [OSTI]

    Tod E. Strohmayer

    2001-01-01T23:59:59.000Z

    High amplitude, nearly coherent X-ray brightness oscillations during thermonuclear X-ray bursts were discovered with the Rossi X-ray Timing Explorer (RXTE) in early 1996. Spectral and timing evidence strongly supports the conclusion that these oscillations are caused by rotational modulation of the burst emission and that they reveal the spin frequency of neutron stars in low mass X-ray binaries, a long sought goal of X-ray astronomy. Studies carried out over the past year have led to the discovery of burst oscillations in four new sources, bringing to ten the number with confirmed burst oscillations. I review the status of our knowledge of these oscillations and indicate how they can be used to probe the physics of neutron stars. For a few burst oscillation sources it has been proposed that the strongest and most ubiquitous frequency is actually the first overtone of the spin frequency and hence that two nearly antipodal hot spots are present on the neutron star. This inference has important implications for both the physics of thermonuclear burning as well as the mass- radius relation for neutron stars, so its confirmation is crucial. I discuss recent attempts to confirm this hypothesis for 4U 1636-53, the source for which a signal at the putative fundamental (290 Hz) has been claimed.

  5. X-ray Pinhole Camera Measurements

    SciTech Connect (OSTI)

    Nelson, D. S. [NSTec; Berninger, M. J. [NSTec; Flores, P. A. [NSTec; Good, D. E. [NSTec; Henderson, D. J. [NSTec; Hogge, K. W. [NSTec; Huber, S. R. [NSTec; Lutz, S. S. [NSTec; Mitchell, S. E. [NSTec; Howe, R. A. [NSTec; Mitton, C. V. [NSTec; Molina, I. [NSTec; Bozman, D. R. [SNL; Cordova, S. R. [SNL; Mitchell, D. R. [SNL; Oliver, B. V. [SNL; Ormond, E. C. [SNL

    2013-07-01T23:59:59.000Z

    The development of the rod pinch diode [1] has led to high-resolution radiography for dynamic events such as explosive tests. Rod pinch diodes use a small diameter anode rod, which extends through the aperture of a cathode plate. Electrons borne off the aperture surface can self-insulate and pinch onto the tip of the rod, creating an intense, small x-ray source (Primary Pinch). This source has been utilized as the main diagnostic on numerous experiments that include high-value, single-shot events. In such applications there is an emphasis on machine reliability, x-ray reproducibility, and x-ray quality [2]. In tests with the baseline rod pinch diode, we have observed that an additional pinch (Secondary Pinch) occurs at the interface near the anode rod and the rod holder. This suggests that stray electrons exist that are not associated with the Primary Pinch. In this paper we present measurements on both pinches using an x-ray pinhole camera. The camera is placed downstream of the Primary Pinch at an angle of 60 with respect to the diode centerline. This diagnostic will be employed to diagnose x-ray reproducibility and quality. In addition, we will investigate the performance of hybrid diodes relating to the formation of the Primary and Secondary Pinches.

  6. Cosmic Ray Interactions in Shielding Materials

    SciTech Connect (OSTI)

    Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Ankney, Austin S.; Orrell, John L.; Berguson, Timothy J.; Troy, Meredith D.

    2011-09-08T23:59:59.000Z

    This document provides a detailed study of materials used to shield against the hadronic particles from cosmic ray showers at Earths surface. This work was motivated by the need for a shield that minimizes activation of the enriched germanium during transport for the MAJORANA collaboration. The materials suitable for cosmic-ray shield design are materials such as lead and iron that will stop the primary protons, and materials like polyethylene, borated polyethylene, concrete and water that will stop the induced neutrons. The interaction of the different cosmic-ray components at ground level (protons, neutrons, muons) with their wide energy range (from kilo-electron volts to giga-electron volts) is a complex calculation. Monte Carlo calculations have proven to be a suitable tool for the simulation of nucleon transport, including hadron interactions and radioactive isotope production. The industry standard Monte Carlo simulation tool, Geant4, was used for this study. The result of this study is the assertion that activation at Earths surface is a result of the neutronic and protonic components of the cosmic-ray shower. The best material to shield against these cosmic-ray components is iron, which has the best combination of primary shielding and minimal secondary neutron production.

  7. Nonlinear X-ray Compton Scattering

    E-Print Network [OSTI]

    Fuchs, Matthias; Chen, Jian; Ghimire, Shambhu; Shwartz, Sharon; Kozina, Michael; Jiang, Mason; Henighan, Thomas; Bray, Crystal; Ndabashimiye, Georges; Bucksbaum, P H; Feng, Yiping; Herrmann, Sven; Carini, Gabriella; Pines, Jack; Hart, Philip; Kenney, Christopher; Guillet, Serge; Boutet, Sebastien; Williams, Garth; Messerschmidt, Marc; Seibert, Marvin; Moeller, Stefan; Hastings, Jerome B; Reis, David A

    2015-01-01T23:59:59.000Z

    X-ray scattering is a weak linear probe of matter. It is primarily sensitive to the position of electrons and their momentum distribution. Elastic X-ray scattering forms the basis of atomic structural determination while inelastic Compton scattering is often used as a spectroscopic probe of both single-particle excitations and collective modes. X-ray free-electron lasers (XFELs) are unique tools for studying matter on its natural time and length scales due to their bright and coherent ultrashort pulses. However, in the focus of an XFEL the assumption of a weak linear probe breaks down, and nonlinear light-matter interactions can become ubiquitous. The field can be sufficiently high that even non-resonant multiphoton interactions at hard X-rays wavelengths become relevant. Here we report the observation of one of the most fundamental nonlinear X-ray-matter interactions, the simultaneous Compton scattering of two identical photons producing a single photon at nearly twice the photon energy. We measure scattered...

  8. Ultrafast X-Ray Coherent Control

    SciTech Connect (OSTI)

    Reis, David

    2009-05-01T23:59:59.000Z

    This main purpose of this grant was to develop the nascent #12;eld of ultrafast x-ray science using accelerator-based sources, and originally developed from an idea that a laser could modulate the di#11;racting properties of a x-ray di#11;racting crystal on a fast enough time scale to switch out in time a shorter slice from the already short x-ray pulses from a synchrotron. The research was carried out primarily at the Advanced Photon Source (APS) sector 7 at Argonne National Laboratory and the Sub-Picosecond Pulse Source (SPPS) at SLAC; in anticipation of the Linac Coherent Light Source (LCLS) x-ray free electron laser that became operational in 2009 at SLAC (all National User Facilities operated by BES). The research centered on the generation, control and measurement of atomic-scale dynamics in atomic, molecular optical and condensed matter systems with temporal and spatial resolution . It helped develop the ultrafast physics, techniques and scienti#12;c case for using the unprecedented characteristics of the LCLS. The project has been very successful with results have been disseminated widely and in top journals, have been well cited in the #12;eld, and have laid the foundation for many experiments being performed on the LCLS, the world's #12;rst hard x-ray free electron laser.

  9. Oscillations During Thermonuclear X-ray Bursts

    E-Print Network [OSTI]

    Tod E. Strohmayer

    2001-01-12T23:59:59.000Z

    High amplitude, nearly coherent X-ray brightness oscillations during thermonuclear X-ray bursts were discovered with the Rossi X-ray Timing Explorer (RXTE) in early 1996. Spectral and timing evidence strongly supports the conclusion that these oscillations are caused by rotational modulation of the burst emission and that they reveal the spin frequency of neutron stars in low mass X-ray binaries, a long sought goal of X-ray astronomy. Studies carried out over the past year have led to the discovery of burst oscillations in four new sources, bringing to ten the number with confirmed burst oscillations. I review the status of our knowledge of these oscillations and indicate how they can be used to probe the physics of neutron stars. For a few burst oscillation sources it has been proposed that the strongest and most ubiquitous frequency is actually the first overtone of the spin frequency and hence that two nearly antipodal hot spots are present on the neutron star. This inference has important implications for both the physics of thermonuclear burning as well as the mass - radius relation for neutron stars, so its confirmation is crucial. I discuss recent attempts to confirm this hypothesis for 4U 1636-53, the source for which a signal at the putative fundamental (290 Hz) has been claimed.

  10. Wave dynamics of regular and chaotic rays

    SciTech Connect (OSTI)

    McDonald, S.W.

    1983-09-01T23:59:59.000Z

    In order to investigate general relationships between waves and rays in chaotic systems, I study the eigenfunctions and spectrum of a simple model, the two-dimensional Helmholtz equation in a stadium boundary, for which the rays are ergodic. Statistical measurements are performed so that the apparent randomness of the stadium modes can be quantitatively contrasted with the familiar regularities observed for the modes in a circular boundary (with integrable rays). The local spatial autocorrelation of the eigenfunctions is constructed in order to indirectly test theoretical predictions for the nature of the Wigner distribution corresponding to chaotic waves. A portion of the large-eigenvalue spectrum is computed and reported in an appendix; the probability distribution of successive level spacings is analyzed and compared with theoretical predictions. The two principal conclusions are: 1) waves associated with chaotic rays may exhibit randomly situated localized regions of high intensity; 2) the Wigner function for these waves may depart significantly from being uniformly distributed over the surface of constant frequency in the ray phase space.

  11. X-ray lithography using holographic images

    DOE Patents [OSTI]

    Howells, Malcolm S. (Berkeley, CA); Jacobsen, Chris (Sound Beach, NY)

    1997-01-01T23:59:59.000Z

    Methods for forming X-ray images having 0.25 .mu.m minimum line widths on X-ray sensitive material are presented. A holgraphic image of a desired circuit pattern is projected onto a wafer or other image-receiving substrate to allow recording of the desired image in photoresist material. In one embodiment, the method uses on-axis transmission and provides a high flux X-ray source having modest monochromaticity and coherence requirements. A layer of light-sensitive photoresist material on a wafer with a selected surface is provided to receive the image(s). The hologram has variable optical thickness and variable associated optical phase angle and amplitude attenuation for transmission of the X-rays. A second embodiment uses off-axis holography. The wafer receives the holographic image by grazing incidence reflection from a hologram printed on a flat metal or other highly reflecting surface or substrate. In this second embodiment, an X-ray beam with a high degree of monochromaticity and spatial coherence is required.

  12. X-ray imaging crystal spectrometer for extended X-ray sources

    DOE Patents [OSTI]

    Bitter, Manfred L. (Princeton, NJ); Fraenkel, Ben (Jerusalem, IL); Gorman, James L. (Bordentown, NJ); Hill, Kenneth W. (Lawrenceville, NJ); Roquemore, A. Lane (Cranbury, NJ); Stodiek, Wolfgang (Princeton, NJ); von Goeler, Schweickhard E. (Princeton, NJ)

    2001-01-01T23:59:59.000Z

    Spherically or toroidally curved, double focusing crystals are used in a spectrometer for X-ray diagnostics of an extended X-ray source such as a hot plasma produced in a tokomak fusion experiment to provide spatially and temporally resolved data on plasma parameters using the imaging properties for Bragg angles near 45. For a Bragg angle of 45.degree., the spherical crystal focuses a bundle of near parallel X-rays (the cross section of which is determined by the cross section of the crystal) from the plasma to a point on a detector, with parallel rays inclined to the main plain of diffraction focused to different points on the detector. Thus, it is possible to radially image the plasma X-ray emission in different wavelengths simultaneously with a single crystal.

  13. X-ray reflectivity and surface roughness

    SciTech Connect (OSTI)

    Ocko, B.M.

    1988-01-01T23:59:59.000Z

    Since the advent of high brightness synchrotron radiation sources there has been a phenomenal growth in the use of x-rays as a probe of surface structure. The technique of x-ray reflectivity is particularly relevant to electrochemists since it is capable of probing the structure normal to an electrode surface in situ. In this paper the theoretical framework for x-ray reflectivity is reviewed and the results from previous non-electrochemistry measurements are summarized. These measurements are from the liquid/air interface (CCl/sub 4/), the metal crystal vacuum interface (Au(100)), and from the liquid/solid interface(liquid crystal/silicon). 34 refs., 5 figs.

  14. X-ray variability in M87

    E-Print Network [OSTI]

    D. E. Harris; J. A. Biretta; W. Junor

    1996-12-05T23:59:59.000Z

    We present the evidence for X-ray variability from the core and from knot A in the M87 jet based on data from two observations with the Einstein Observatory High Resolution Imager (HRI) and three observations with the ROSAT HRI. The core intensity showed a 16% increase in 17 months ('79-'80); a 12% increase in the 3 years '92 to '95; and a 17% drop in the last half of 1995. The intensity of knot A appears to have decreased by 16% between 92Jun and 95Dec. Although the core variability is consistent with general expectations for AGN nuclei, the changes in knot A provide constraints on the x-ray emission process and geometry. Thus we predict that the x-ray morphology of knot A will differ significantly from the radio and optical structure.

  15. Combined microstructure x-ray optics

    SciTech Connect (OSTI)

    Barbee, T.W. Jr.

    1989-02-01T23:59:59.000Z

    Multilayers are man-made microstructures which vary in depth and are now of sufficient quality to be used as x-ray, soft x-ray and extreme ultraviolet optics. Gratings are man-made in plane microstructures which have been used as optic elements for most of this century. Joining of these two optical microstructures to form combined microstructure optical microstructures to form combined microstructure optical elements has the potential for greatly enhancing both the throughput and the resolution attainable in these spectral ranges. The characteristics of these new optic elements will be presented and compared to experiment with emphasis on the unique properties of these combined microstructures. These results reported are general in nature and not limited to the soft x-ray or extreme ultraviolet spectral domains and also apply to neutrons. 19 refs., 7 figs., 4 tabs.

  16. Life Extinctions By Cosmic Ray Bursts

    E-Print Network [OSTI]

    Arnon Dar; Ari Laor; Nir J. Shaviv

    1997-05-02T23:59:59.000Z

    High energy cosmic ray jets from nearby mergers or accretion induced collapse (AIC) of neutron stars (NS) that hit the atmosphere can produce lethal fluxes of atmospheric muons at ground level, underground and underwater, destroy the ozone layer and radioactivate the environment. They could have caused most of the massive life extinctions on planet Earth in the past 600 My. Biological mutations due to ionizing radiations could have caused the fast appearance of new species after the massive extinctions. An early warning of future extinctions due to NS mergers may be obtained by identifying, mapping and timing all the nearby binary neutron stars systems. A warning of an approaching cosmic ray burst from a nearby NS merger/AIC may be provided by a very intense gamma ray burst which preceeds it.

  17. CAN ULTRAHIGH-ENERGY COSMIC RAYS COME FROM GAMMA-RAY BURSTS? COSMIC RAYS BELOW THE ANKLE AND GALACTIC GAMMA-RAY BURSTS

    SciTech Connect (OSTI)

    Eichler, David [Physics Department, Ben-Gurion University, Be'er-Sheva 84105 (Israel); Pohl, Martin [Institut fuer Physik und Astronomie, Universitaet Potsdam, 14476 Potsdam-Golm (Germany)

    2011-09-10T23:59:59.000Z

    The maximum cosmic-ray energy achievable by acceleration by a relativistic blast wave is derived. It is shown that forward shocks from long gamma-ray bursts (GRBs) in the interstellar medium accelerate protons to large enough energies, and have a sufficient energy budget, to produce the Galactic cosmic-ray component just below the ankle at 4 x 10{sup 18} eV, as per an earlier suggestion. It is further argued that, were extragalactic long GRBs responsible for the component above the ankle as well, the occasional Galactic GRB within the solar circle would contribute more than the observational limits on the outward flux from the solar circle, unless an avoidance scenario, such as intermittency and/or beaming, allows the present-day local flux to be less than 10{sup -3} of the average. Difficulties with these avoidance scenarios are noted.

  18. Fermi Observations of Gamma-ray Bursts

    SciTech Connect (OSTI)

    Ohno, Masanori [Institute of Space and Astronautical Science, JAXA, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan)

    2010-10-15T23:59:59.000Z

    The gamma-ray emission mechanism of Gamma-ray bursts (GRBs) are still unknown. Fermi Gamma-ray Space Telescope successfully detected high-energy (> 100 MeV) emission from 17 GRBs since its launch. Fermi revealed the distinct temporal behaviors and extra spectral component from high-energy emission. These new observational results are driving many theoretical implications, such as leptonic, hadronic and afterglow origin. The highest energy photon detected by Fermi gives a constraint on the bulk Lorentz factor of the ultra-relativistic jets of GRBs. The impact of the Fermi GRB observations extends not only to the GRB-related issues but also to the outside GRB physics, such as quantum gravity and model of the extra galactic background light.

  19. The X-ray/submillimetre link

    E-Print Network [OSTI]

    O. Almaini

    2000-01-07T23:59:59.000Z

    It is widely believed that most of the cosmic X-ray background (XRB) is produced by a vast, hitherto undetected population of obscured AGN. Deep X-ray surveys with Chandra and XMM will soon test this hypothesis. Similarly, recent sub-mm surveys with SCUBA have revealed an analogous population of exceptionally luminous, dust-enshrouded {\\em star-forming} galaxies at high redshift. There is now growing evidence for an intimate link between these obscured populations. There are currently large uncertainties in the models, but several independent arguments lead to the conclusion that a significant fraction of the SCUBA sources ($10-30% $) will contain quasars. Recent observational studies of SCUBA survey sources appear to confirm these predictions, although the relative roles of AGN and star-forming activity in heating the dust are unclear. Forthcoming surveys combining X-ray and sub-mm observations will provide a very powerful tool for disentangling these processes.

  20. X-ray atlas of rheumatic diseases

    SciTech Connect (OSTI)

    Dihlmann, W.

    1986-01-01T23:59:59.000Z

    This atlas comprises instructive X-rays of the various inflammatory rheumatic joint diseases in all stages at the extremities and the spinal column. In addition, the complex pattern of the wide range of arthroses, also known as degenerative rheumatic disease is included. Besides the instructive pointers to X-ray diagnosis, the book is also a guide to differential diagnosis. Hence, this book is actually an X-ray atlas of joint diseases in general. Selected Contents: Introduction: What Does ''Rheumatism'' Actually Mean./Radiographic Methodology in Rheumatic Diseases of the Locomotor System/The Mosaic of Arthritis/Adult Rheumatoid Arthritis/Seronegative Spondylarthritis/Classic Collagen Diseases/Enthesiopathies/Gout-Pseudogout

  1. HETEROGENEITY IN SHORT GAMMA-RAY BURSTS

    SciTech Connect (OSTI)

    Norris, Jay P. [Physics and Astronomy Department, University of Denver, Denver, CO 80208 (United States); Gehrels, Neil [Astroparticle Physics Laboratory, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Scargle, Jeffrey D. [Space Science and Astrobiology Division, NASA/Ames Research Center, Moffett Field, CA 94035-1000 (United States)

    2011-07-01T23:59:59.000Z

    We analyze the Swift/BAT sample of short gamma-ray bursts, using an objective Bayesian Block procedure to extract temporal descriptors of the bursts' initial pulse complexes (IPCs). The sample is comprised of 12 and 41 bursts with and without extended emission (EE) components, respectively. IPCs of non-EE bursts are dominated by single pulse structures, while EE bursts tend to have two or more pulse structures. The medians of characteristic timescales-durations, pulse structure widths, and peak intervals-for EE bursts are factors of {approx}2-3 longer than for non-EE bursts. A trend previously reported by Hakkila and colleagues unifying long and short bursts-the anti-correlation of pulse intensity and width-continues in the two short burst groups, with non-EE bursts extending to more intense, narrower pulses. In addition, we find that preceding and succeeding pulse intensities are anti-correlated with pulse interval. We also examine the short burst X-ray afterglows as observed by the Swift/X-Ray Telescope (XRT). The median flux of the initial XRT detections for EE bursts ({approx}6x10{sup -10} erg cm{sup -2} s{sup -1}) is {approx}>20x brighter than for non-EE bursts, and the median X-ray afterglow duration for EE bursts ({approx}60,000 s) is {approx}30x longer than for non-EE bursts. The tendency for EE bursts toward longer prompt-emission timescales and higher initial X-ray afterglow fluxes implies larger energy injections powering the afterglows. The longer-lasting X-ray afterglows of EE bursts may suggest that a significant fraction explode into denser environments than non-EE bursts, or that the sometimes-dominant EE component efficiently powers the afterglow. Combined, these results favor different progenitors for EE and non-EE short bursts.

  2. Energy resolved X-ray grating interferometry

    SciTech Connect (OSTI)

    Thuering, T.; Stampanoni, M. [Swiss Light Source, Paul Scherrer Institut, Villigen PSI (Switzerland) [Swiss Light Source, Paul Scherrer Institut, Villigen PSI (Switzerland); Institute for Biomedical Engineering, Swiss Federal Institute of Technology, Zurich (Switzerland); Barber, W. C.; Iwanczyk, J. S. [DxRay, Inc., Northridge, California 91324 (United States)] [DxRay, Inc., Northridge, California 91324 (United States); Seo, Y.; Alhassen, F. [UCSF Physics Research Laboratory, Department of Radiology and Biomedical Imaging, University of California, San Francisco, California 94143 (United States)] [UCSF Physics Research Laboratory, Department of Radiology and Biomedical Imaging, University of California, San Francisco, California 94143 (United States)

    2013-05-13T23:59:59.000Z

    Although compatible with polychromatic radiation, the sensitivity in X-ray phase contrast imaging with a grating interferometer is strongly dependent on the X-ray spectrum. We used an energy resolving detector to quantitatively investigate the dependency of the noise from the spectral bandwidth and to consequently optimize the system-by selecting the best energy band matching the experimental conditions-with respect to sensitivity maximization and, eventually, dose. Further, since theoretical calculations of the spectrum are usually limited due to non-ideal conditions, an energy resolving detector accurately quantifies the spectral changes induced by the interferometer including flux reduction and beam hardening.

  3. Cosmic-ray Muon Flux In Belgrade

    SciTech Connect (OSTI)

    Banjanac, R.; Dragic, A.; Jokovic, D.; Udovicic, V. [Institute of Physics, University of Belgrade, Belgrade (Serbia and Montenegro); Puzovic, J.; Anicin, I. [Faculty of Physics, University of Belgrade, Belgrade (Serbia and Montenegro)

    2007-04-23T23:59:59.000Z

    Two identical plastic scintillator detectors, of prismatic shape (50x23x5)cm similar to NE102, were used for continuous monitoring of cosmic-ray intensity. Muon {delta}E spectra have been taken at five minute intervals, simultaneously from the detector situated on the ground level and from the second one at the depth of 25 m.w.e in the low-level underground laboratory. Sum of all the spectra for the years 2002-2004 has been used to determine the cosmic-ray muon flux at the ground level and in the underground laboratory.

  4. Status of the Milagro $\\gamma$ Ray Observatory

    E-Print Network [OSTI]

    Atkins, R; Berley, D; Chen, M L; Coyne, D G; Delay, R S; Dingus, B L; Dorfan, D E; Ellsworth, R W; Evans, D; Falcone, A D; Fleysher, L; Fleysher, R; Gisler, G; Goodman, J A; Haines, T J; Hoffman, C M; Hugenberger, S; Kelley, L A; Leonor, I; Macri, J R; McConnell, M; McCullough, J F; McEnery, J E; Miller, R S; Mincer, A I; Morales, M F; Nmethy, P; Ryan, J M; Schneider, M; Shen, B; Shoup, A L; Sinnis, G; Smith, A J; Sullivan, G W; Thompson, T N; Tmer, T O; Wang, K; Wascko, M O; Westerhoff, S; Williams, D A; Yang, T; Yodh, G B

    2001-01-01T23:59:59.000Z

    The Milagro Gamma Ray Observatory is the world's first large-area water Cherenkov detector capable of continuously monitoring the sky at TeV energies. Located in northern New Mexico, Milagro will perform an all sky survey of the Northern Hemisphere at energies between ~250 GeV and 50 TeV. With a high duty cycle, large detector area (~5000 square meters), and a wide field-of-view (~1 sr), Milagro is uniquely capable of searching for transient and DC sources of high-energy gamma-ray emission. Milagro has been operating since February, 1999. The current status of the Milagro Observatory and initial results will be discussed.

  5. Gamma-ray bursts with ROSAT

    E-Print Network [OSTI]

    J. Greiner

    1997-04-01T23:59:59.000Z

    I review the use of ROSAT over the last years for the investigation of well localized gamma-ray burst (GRB) error boxes. In particular, I cover (i) the systematic study of several dozens of IPN locations using the ROSAT All-Sky-Survey data, (ii) results of deep ROSAT pointings of selected small GRB error boxes, (iii) the attempts for and results of quick follow-up observations after GRB events including the three GRBs localized with BeppoSAX, (iv) the correlation of GRB locations with serendipitous ROSAT pointings and (v) the search for X-ray flashes in the database of pointed ROSAT observations.

  6. Gamma-Ray Bursts: Jets and Energetics

    E-Print Network [OSTI]

    D. A. Frail

    2003-11-12T23:59:59.000Z

    The relativistic outflows from gamma-ray bursts are now thought to be narrowly collimated into jets. After correcting for this jet geometry there is a remarkable constancy of both the energy radiated by the burst and the kinetic energy carried by the outflow. Gamma-ray bursts are still the most luminous explosions in the Universe, but they release energies that are comparable to supernovae. The diversity of cosmic explosions appears to be governed by the fraction of energy that is coupled to ultra-relativistic ejecta.

  7. Status of the Milagro Gamma Ray Observatory

    E-Print Network [OSTI]

    R. Atkins; W. Benbow; D. Berley; M. -L. Chen; D. G. Coyne; R. S. Delay; B. L. Dingus; D. E. Dorfan; R. W. Ellsworth; D. Evans; A. Falcone; L. Fleysher; R. Fleysher; G. Gisler; J. A. Goodman; T. J. Haines; C. M. Hoffman; S. Hugenberger; L. A. Kelley; I. Leonor; J. Macri; M. McConnell; J. F. McCullough; J. E. McEnery; R. S. Miller; A. I. Mincer; M. F. Morales; P. Nemethy; J. M. Ryan; M. Schneider; B. Shen; A. Shoup; G. Sinnis; A. J. Smith; G. W. Sullivan; T. N. Thompson; O. T. Tumer; K. Wang; M. O. Wascko; S. Westerhoff; D. A. Williams; T. Yang; G. B. Yodh

    1999-06-24T23:59:59.000Z

    The Milagro Gamma Ray Observatory is the world's first large-area water Cherenkov detector capable of continuously monitoring the sky at TeV energies. Located in northern New Mexico, Milagro will perform an all sky survey of the Northern Hemisphere at energies between ~250 GeV and 50 TeV. With a high duty cycle, large detector area (~5000 square meters), and a wide field-of-view (~1 sr), Milagro is uniquely capable of searching for transient and DC sources of high-energy gamma-ray emission. Milagro has been operating since February, 1999. The current status of the Milagro Observatory and initial results will be discussed.

  8. Radiobiological studies using gamma and x rays.

    SciTech Connect (OSTI)

    Potter, Charles Augustus; Longley, Susan W.; Scott, Bobby R. [Lovelace Respiratory Research Institute, Albuquerque, NM; Lin, Yong [Lovelace Respiratory Research Institute, Albuquerque, NM; Wilder, Julie [Lovelace Respiratory Research Institute, Albuquerque, NM; Hutt, Julie A. [Lovelace Respiratory Research Institute, Albuquerque, NM; Padilla, Mabel T. [Lovelace Respiratory Research Institute, Albuquerque, NM; Gott, Katherine M. [Lovelace Respiratory Research Institute, Albuquerque, NM

    2013-02-01T23:59:59.000Z

    There are approximately 500 self-shielded research irradiators used in various facilities throughout the U.S. These facilities use radioactive sources containing either 137Cs or 60Co for a variety of biological investigations. A report from the National Academy of Sciences[1] described the issues with security of particular radiation sources and the desire for their replacement. The participants in this effort prepared two peer-reviewed publications to document the results of radiobiological studies performed using photons from 320-kV x rays and 137Cs on cell cultures and mice. The effectiveness of X rays was shown to vary with cell type.

  9. Time-resolved x-ray diagnostics

    SciTech Connect (OSTI)

    Lyons, P.B.

    1981-01-01T23:59:59.000Z

    Techniques for time-resolved x-ray diagnostics will be reviewed with emphasis on systems utilizing x-ray diodes or scintillators. System design concerns for high-bandwidth (> 1 GHz) diagnostics will be emphasized. The limitations of a coaxial cable system and a technique for equalizing to improve bandwidth of such a system will be reviewed. Characteristics of new multi-GHz amplifiers will be presented. An example of a complete operational system on the Los Alamos Helios laser will be presented which has a bandwidth near 3 GHz over 38 m of coax. The system includes the cable, an amplifier, an oscilloscope, and a digital camera readout.

  10. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 LawrenceE C H NLensless X-RayLensless X-Ray

  11. A supersymmetric model of gamma ray bursts

    E-Print Network [OSTI]

    L. Clavelli; G. Karatheodoris

    2005-08-08T23:59:59.000Z

    We propose a model for gamma ray bursts in which a star subject to a high level of fermion degeneracy undergoes a phase transition to a supersymmetric state. The burst is initiated by the transition of fermion pairs to sfermion pairs which, uninhibited by the Pauli exclusion principle, can drop to the ground state of minimum momentum through photon emission. The jet structure is attributed to the Bose statistics of sfermions whereby subsequent sfermion pairs are preferentially emitted into the same state (sfermion amplification by stimulated emission). Bremsstrahlung gamma rays tend to preserve the directional information of the sfermion momenta and are themselves enhanced by stimulated emission.

  12. Redshift indicators for gamma-ray bursts

    E-Print Network [OSTI]

    J-L. Atteia

    2005-05-04T23:59:59.000Z

    The measure of the distances and luminosities of gamma-ray bursts (GRBs) led to the discovery that many GRB properties are strongly correlated with their intrinsic luminosity, leading to the construction of reliable luminosity indicators. These GRB luminosity indicators have quickly found applications, like the construction of 'pseudo-redshifts', or the measure of luminosity distances, which can be computed independently of the measure of the redshift. In this contribution I discuss various issues connected with the construction of luminosity-redshift indicators for gamma-ray bursts.

  13. Theoretical standards in x-ray spectroscopies

    SciTech Connect (OSTI)

    Not Available

    1992-01-01T23:59:59.000Z

    We propose to extend our state-of-the-art, ab initio XAFS (X-ray absorption fine structure) codes, FEFF. Our current work has been highly successful in achieving accurate, user-friendly XAFS standards, exceeding the performance of both tabulated standards and other codes by a considerable margin. We now propose to add the capability to treat more complex materials. This includes multiple-scattering, polarization dependence, an approximate treatment of XANES (x-ray absorption near edge structure), and other improvements. We also plan to adapt FEFF to other spectroscopies, e.g. photoelectron diffraction (PD) and diffraction anomalous fine structure (DAFS).

  14. X-Ray Nanoimaging: Instruments and Methods

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered energy consumption byAbout SRNL Home SRNL main campusMore thanX-Ray Imaging ofX-Ray

  15. X-ray Computed Tomography | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered energy consumption byAbout SRNL Home SRNL main campusMore thanX-Ray ImagingfeedX-ray

  16. Ultra-high energy cosmic rays, cascade gamma-rays, and high-energy neutrinos from gamma-ray bursts

    E-Print Network [OSTI]

    Charles D. Dermer; Armen Atoyan

    2006-06-26T23:59:59.000Z

    Gamma-ray bursts (GRBs) are sources of energetic, highly variable fluxes of gamma rays, which demonstrates that they are powerful particle accelerators. Besides relativistic electrons, GRBs should also accelerate high-energy hadrons, some of which could escape cooling to produce ultra-high energy cosmic rays (UHECRs). Acceleration of high-energy hadrons in GRB blast waves will be established if high-energy neutrinos produced through photopion interactions in the blast wave are detected from GRBs. Limitations on the energy in nonthermal hadrons and the number of expected neutrinos are imposed by the fluxes from pair-photon cascades initiated in the same processes that produce neutrinos. Only the most powerful bursts at fluence levels >~ 3e-4 erg/cm^2 offer a realistic prospect for detection of >> TeV neutrinos. Detection of high-energy neutrinos is likely if GRB blast waves have large baryon loads and Doppler factors <~ 200. Cascade gamma rays will accompany neutrino production and might already have been detected as anomalous emission components in the spectra of some GRBs. Prospects for detection of GRBs in the Milky Way are also considered.

  17. Modeling Gamma-Ray Burst X-Ray Flares within the Internal Shock Model

    E-Print Network [OSTI]

    Maxham, Amanda

    2009-01-01T23:59:59.000Z

    X-ray afterglow light curves have been collected for over 400 Swift gamma-ray bursts with nearly half of them having X-ray flares superimposed on the regular afterglow decay. Evidence suggests that gamma-ray prompt emission and X-ray flares share a common origin and that at least some flares can only be explained by long-lasting central engine activity. We have developed a shell model code to address the question of how X-ray flares are produced within the framework of the internal shock model. The shell model creates randomized GRB explosions from a central engine with multiple shells and follows those shells as they collide, merge and spread, producing prompt emission and X-ray flares. We pay special attention to the time history of central engine activity, internal shocks, and observed flares, but do not calculate the shock dynamics and radiation processes in detail. Using the empirical E_p - E_iso (Amati) relation with an assumed Band function spectrum for each collision and an empirical flare temporal pr...

  18. Hard x-ray or gamma ray laser by a dense electron beam

    E-Print Network [OSTI]

    S. Son; S. J. Moon

    2012-02-12T23:59:59.000Z

    A coherent x-ray or gamma ray can be created from a dense electron beam propagating through an intense laser undulator. It is analyzed by using the Landau damping theory which suits better than the conventional linear analysis for the free electron laser, as the electron beam energy spread is high. The analysis suggests that the currently available physical parameters would enable the generation of the coherent gamma ray of up to 100 keV. The electron quantum diffraction suppresses the FEL action, by which the maximum radiation energy to be generated is limited.

  19. Green's functions for transmission of X-rays and gamma-rays through cold media

    E-Print Network [OSTI]

    P. Magdziarz; A. A. Zdziarski

    1996-07-03T23:59:59.000Z

    Using a Monte Carlo method, we study Compton scattering and absorption of X-rays and gamma-rays in cold media. We consider transmission of X/gamma-rays through a shell of an arbitrary optical depth, for which we derive energy-dependent Green's functions. Fitting the Green functions with simple analytical formulae is in progress. We also present a simple treatment of the effect of absorption on Green's functions for Compton scattering, which allow to treat media with an arbitrary ionization state and chemical composition. Our transmission Green's functions allow to treat Thomson-thick absorbers, e.g. molecular tori of Seyfert 2s.

  20. X-ray microscopy using grazing-incidence reflections optics

    SciTech Connect (OSTI)

    Price, R.H.

    1983-06-30T23:59:59.000Z

    The role of Kirkpatrick-Baez microscopes as the workhorse of the x-ray imaging devices is discussed. This role is being extended with the development of a 22X magnification Kirkpatrick-Baez x-ray microscope with multilayer x-ray mirrors. These mirrors can operate at large angles, high x-ray energies, and have a narrow, well defined x-ray energy bandpass. This will make them useful for numerous experiments. However, where a large solid angle is needed, the Woelter microscope will still be necessary and the technology needed to build them will be useful for many other types of x-ray optics.

  1. X-ray microscopy using grazing-incidence reflection optics

    SciTech Connect (OSTI)

    Price, R.H.

    1981-08-06T23:59:59.000Z

    The Kirkpatrick-Baez microscopes are described along with their role as the workhorse of the x-ray imaging devices. This role is being extended with the development of a 22X magnification Kirkpatrick-Baez x-ray microscope with multilayer x-ray mirrors. These mirrors can operate at large angles, high x-ray energies, and have a narrow, well defined x-ray energy bandpass. This will make them useful for numerous experiments. However, where a large solid angle is needed, the Woelter microscope will still be necessary and the technology needed to build them will be useful for many other types of x-ray optics.

  2. Rise Time Measurement for Ultrafast X-Ray Pulses

    DOE Patents [OSTI]

    Celliers, Peter M.; Weber, Franz A.; Moon, Stephen J.

    2005-04-05T23:59:59.000Z

    A pump-probe scheme measures the rise time of ultrafast x-ray pulses. Conventional high speed x-ray diagnostics (x-ray streak cameras, PIN diodes, diamond PCD devices) do not provide sufficient time resolution to resolve rise times of x-ray pulses on the order of 50 fs or less as they are being produced by modern fast x-ray sources. Here, we are describing a pump-probe technique that can be employed to measure events where detector resolution is insufficient to resolve the event. The scheme utilizes a diamond plate as an x-ray transducer and a p-polarized probe beam.

  3. Rise time measurement for ultrafast X-ray pulses

    DOE Patents [OSTI]

    Celliers, Peter M. (Berkeley, CA); Weber, Franz A. (Oakland, CA); Moon, Stephen J. (Tracy, CA)

    2005-04-05T23:59:59.000Z

    A pump-probe scheme measures the rise time of ultrafast x-ray pulses. Conventional high speed x-ray diagnostics (x-ray streak cameras, PIN diodes, diamond PCD devices) do not provide sufficient time resolution to resolve rise times of x-ray pulses on the order of 50 fs or less as they are being produced by modern fast x-ray sources. Here, we are describing a pump-probe technique that can be employed to measure events where detector resolution is insufficient to resolve the event. The scheme utilizes a diamond plate as an x-ray transducer and a p-polarized probe beam.

  4. Small Angle X-Ray Scattering Detector

    DOE Patents [OSTI]

    Hessler, Jan P. (Downers Grove, IL)

    2004-06-15T23:59:59.000Z

    A detector for time-resolved small-angle x-ray scattering includes a nearly constant diameter, evacuated linear tube having an end plate detector with a first fluorescent screen and concentric rings of first fiber optic bundles for low angle scattering detection and an annular detector having a second fluorescent screen and second fiber optic bundles concentrically disposed about the tube for higher angle scattering detection. With the scattering source, i.e., the specimen under investigation, located outside of the evacuated tube on the tube's longitudinal axis, scattered x-rays are detected by the fiber optic bundles, to each of which is coupled a respective photodetector, to provide a measurement resolution, i.e., dq/q, where q is the momentum transferred from an incident x-ray to an x-ray scattering specimen, of 2% over two (2) orders of magnitude in reciprocal space, i.e., q.sub.max /q.sub.min.congruent.100.

  5. SLAC All Access: X-ray Microscope

    ScienceCinema (OSTI)

    Nelson, Johanna; Liu, Yijin

    2014-06-13T23:59:59.000Z

    SLAC physicists Johanna Nelson and Yijin Liu give a brief overview of the X-ray microscope at the Stanford Synchrotron Radiation Lightsource (SSRL) that is helping improve rechargeable-battery technology by letting researchers peek into the inner workings of batteries as they operate.

  6. Political Science Ray V. Christensen, Chair

    E-Print Network [OSTI]

    Hart, Gus

    Political Science Ray V. Christensen, Chair 745 SWKT, (801) 422-5133 College of Family, Home programs in the Department of Political Science are open enrollment. The Discipline The political science in all things." Politics extends far beyond the immediate concerns of politicians or pollsters

  7. Numerical likelihood analysis of cosmic ray anisotropies

    SciTech Connect (OSTI)

    Carlos Hojvat et al.

    2003-07-02T23:59:59.000Z

    A numerical likelihood approach to the determination of cosmic ray anisotropies is presented which offers many advantages over other approaches. It allows a wide range of statistically meaningful hypotheses to be compared even when full sky coverage is unavailable, can be readily extended in order to include measurement errors, and makes maximum unbiased use of all available information.

  8. X-ray spectroscopy of manganese clusters

    SciTech Connect (OSTI)

    Grush, M.M. [Univ. of California, Davis, CA (United States). Dept. of Applied Science; [Lawrence Berkeley National Lab., CA (United States). Energy and Environment Div.

    1996-06-01T23:59:59.000Z

    Much of this thesis represents the groundwork necessary in order to probe Mn clusters more productively than with conventional Mn K-edge XAS and is presented in Part 1. Part 2 contains the application of x-ray techniques to Mn metalloproteins and includes a prognosis at the end of each chapter. Individual Mn oxidation states are more readily distinguishable in Mn L-edge spectra. An empirical mixed valence simulation routine for determining the average Mn oxidation state has been developed. The first Mn L-edge spectra of a metalloprotein were measured and interpreted. The energy of Mn K{beta} emission is strongly correlated with average Mn oxidation state. K{beta} results support oxidation states of Mn(III){sub 2}(IV){sub 2} for the S{sub 1} state of Photosystem II chemical chemically reduced preparations contain predominantly Mn(II). A strength and limitation of XAS is that it probes all of the species of a particular element in a sample. It would often be advantageous to selectively probe different forms of the same element. The first demonstration that chemical shifts in x-ray fluorescence energies can be used to obtain oxidation state-selective x-ray absorption spectra is presented. Spin-dependent spectra can also be used to obtain a more simplified picture of local structure. The first spin-polarized extended x-ray absorption fine structure using Mn K{beta} fluorescence detection is shown.

  9. Accelerator Data for Cosmic Ray Physics

    E-Print Network [OSTI]

    M. G. Albrow

    2010-09-21T23:59:59.000Z

    I present selected examples of accelerator data, mainly from hadron colliders, that are relevant for understanding cosmic ray showers. I focus on the forward region, $x_{Feynman} > 0.05$, where high energy data are scarce, since the emphasis in collider physics became high-$p_T$ phenomena.

  10. Multiple wavelength X-ray monochromators

    DOE Patents [OSTI]

    Steinmeyer, P.A.

    1992-11-17T23:59:59.000Z

    An improved apparatus and method is provided for separating input x-ray radiation containing first and second x-ray wavelengths into spatially separate first and second output radiation which contain the first and second x-ray wavelengths, respectively. The apparatus includes a crystalline diffractor which includes a first set of parallel crystal planes, where each of the planes is spaced a predetermined first distance from one another. The crystalline diffractor also includes a second set of parallel crystal planes inclined at an angle with respect to the first set of crystal planes where each of the planes of the second set of parallel crystal planes is spaced a predetermined second distance from one another. In one embodiment, the crystalline diffractor is comprised of a single crystal. In a second embodiment, the crystalline diffractor is comprised of a stack of two crystals. In a third embodiment, the crystalline diffractor includes a single crystal that is bent for focusing the separate first and second output x-ray radiation wavelengths into separate focal points. 3 figs.

  11. November 25, 2002 Dr. Ray Orbach

    E-Print Network [OSTI]

    available energy source, including no emissions of carbon dioxide, no risk of a severe accident, no long-scale energy storage. Fusion can be used to produce electricity and hydrogen, and can provide energyNovember 25, 2002 Dr. Ray Orbach Director, Office of Science U.S. Department of Energy 1000

  12. Clusters in Very High Energy Cosmic Rays

    E-Print Network [OSTI]

    A. A. Mikhailov

    2004-03-19T23:59:59.000Z

    Arrival directions of cosmic rays with the energy E>4.10^{19} eV are analyzed by using data of the Yakutsk and AGASA (Japan) extensive air showers (EAS) arrays. It is supposed that the clusters can be formed as a result of decay of superheavy particles. The consequences of this supposition compare with experimental data.

  13. Current segmented gamma-ray scanner technology

    SciTech Connect (OSTI)

    Bjork, C.W.

    1987-01-01T23:59:59.000Z

    A new generation of segmented gamma-ray scanners has been developed at Los Alamos for scrap and waste measurements at the Savannah River Plant and the Los Alamos Plutonium Facility. The new designs are highly automated and exhibit special features such as good segmentation and thorough shielding to improve performance.

  14. Gamma-ray bursts: a Centauro's cry?

    E-Print Network [OSTI]

    Z. K. Silagadze

    2003-06-30T23:59:59.000Z

    A new candidate for the gamma-ray bursts central engine is proposed: if in some energetic cosmic event a macroscopic amount of bubbles of the disoriented chiral condensate can be formed, then their subsequent decays will produce a relativistic fireball without the baryon loading problem. The neutron star to strange star transition is considered as a candidate example of such cosmic event.

  15. A supersymmetric origin of gamma ray bursts

    E-Print Network [OSTI]

    L. Clavelli

    2004-10-04T23:59:59.000Z

    Bright bursts of gamma rays from outer space have been puzzling Astronomers for more than thirty years and there is still no conceptually complete model for the phenomenon within the standard model of particle physics. Is it time to consider a supersymmetric (SUSY) origin for these bursts to add to the astronomical indications of supersymmetry from dark matter?

  16. Neutrino Balls and Gamma-Ray Bursts

    E-Print Network [OSTI]

    B. Holdom; R. A. Malaney

    1993-06-17T23:59:59.000Z

    We propose a mechanism by which the neutrino emission from a supernova-type explosion can be converted into a gamma-ray burst of total energy $\\sim 10^{50}$ ergs. This occurs naturally if the explosion is situated inside a ball of trapped neutrinos, which in turn may lie at a galactic core. There are possible unique signatures of this scenario.

  17. Catalog of supersoft X-ray sources

    E-Print Network [OSTI]

    J. Greiner

    2000-05-11T23:59:59.000Z

    This catalog comprises an up-to-date (December 1999) list of luminous (>10^36 erg/s), binary supersoft X-ray sources. This electronic version (including the accompannying Web-pages) supersedes the printed version of Greiner (1996).

  18. High redshift Gamma-Ray Bursts

    E-Print Network [OSTI]

    Salvaterra, R

    2015-01-01T23:59:59.000Z

    Ten years of operations of the Swift satellite have allow us to collect a small sample of long Gamma-Ray Bursts (GRBs) at redshift larger than six. I will review here the present status of this research field and discuss the possible use of GRBs as a fundamental new tool to explore the early Universe, complementary to quasar and galaxy surveys.

  19. The early X-ray afterglows of optically bright and dark Gamma-Ray Bursts

    E-Print Network [OSTI]

    Yi-Qing Lin

    2006-04-08T23:59:59.000Z

    A systematical study on the early X-ray afterglows of both optically bright and dark gamma-ray bursts (B-GRBs and D-GRBs) observed by Swift has been presented. Our sample includes 25 GRBs. Among them 13 are B-GRBs and 12 are D-GRBs. Our results show that the distributions of the X-ray afterglow fluxes ($F_{X}$), the gamma-ray fluxes ($S_{\\gamma}$), and the ratio ($R_{\\gamma, X}$) for both the D-GRBs and B-GRBs are similar. The differences of these distributions for the two kinds of GRBs should be statistical fluctuation. These results indicate that the progenitors of the two kinds of GRBs are the same population. Their total energy explosions are comparable. The suppression of the optical emissions from D-GRBs should results from circumburst but not their central engine.

  20. On the spectrum of Ultrahigh Energy Cosmic Rays and the Gamma Ray Burst Origin Hypothesis

    E-Print Network [OSTI]

    S. T. Scully; F. W. Stecker

    2001-03-21T23:59:59.000Z

    It has been suggested that cosmological gamma-ray bursts (GRBs) can produce the observed flux of cosmic rays at the highest energies. However, recent studies of GRBs indicate that their redshift distribution likely follows that of the average star formation rate and that GRBs were more numerous at high redshifts. As a consequence, we show that photomeson production energy losses suffered by ultrahigh energy cosmic rays coming from GRBs would produce too sharp a spectral high energy cutoff to be consistent with the air shower data. Furthermore, we show that cosmological GRBs fail to supply the energy input required to account for the cosmic ray flux above 10 EeV by a factor of 100-1000.

  1. X-ray flares from dense shells formed in gamma-ray burst explosions

    E-Print Network [OSTI]

    Hascoet, R; Daigne, F; Mochkovitch, R

    2015-01-01T23:59:59.000Z

    Bright X-ray flares are routinely detected by the Swift satellite during the early afterglow of gamma-ray bursts, when the explosion ejecta drives a blast wave into the external medium. We suggest that the flares are produced as the reverse shock propagates into the tail of the ejecta. The ejecta is expected to contain a few dense shells formed at an earlier stage of the explosion. We show an example of how such dense shells form and describe how the reverse shock interacts with them. A new reflected shock is generated in this interaction, which produces a short-lived X-ray flare. The model provides a natural explanation for the main observed features of the X-ray flares --- the fast rise, the steep power-law decline, and the characteristic peak duration \\Delta t /t= (0.1-0.3).

  2. X-ray afterglows and spectroscopy of Gamma-Ray Bursts

    E-Print Network [OSTI]

    Luigi Piro

    2004-02-26T23:59:59.000Z

    I will review the constraints set by X-ray measurements of afterglows on several issues of GRB, with particular regard to the fireball model, the environment, the progenitor and dark GRB.

  3. X-RAY POINT-SOURCE POPULATIONS CONSTITUTING THE GALACTIC RIDGE X-RAY EMISSION

    SciTech Connect (OSTI)

    Morihana, Kumiko [Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)] [Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Tsujimoto, Masahiro; Ebisawa, Ken [Japan Aerospace Exploration Agency, Institute of Space and Astronautical Science, 3-1-1 Yoshino-dai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan)] [Japan Aerospace Exploration Agency, Institute of Space and Astronautical Science, 3-1-1 Yoshino-dai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan); Yoshida, Tessei, E-mail: morihana@crab.riken.jp [National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo 181-8588 (Japan)] [National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo 181-8588 (Japan)

    2013-03-20T23:59:59.000Z

    Apparently diffuse X-ray emission has been known to exist along the central quarter of the Galactic Plane since the beginning of X-ray astronomy; this is referred to as the Galactic Ridge X-ray emission (GRXE). Recent deep X-ray observations have shown that numerous X-ray point sources account for a large fraction of the GRXE in the hard band (2-8 keV). However, the nature of these sources is poorly understood. Using the deepest X-ray observations made in the Chandra bulge field, we present the result of a coherent photometric and spectroscopic analysis of individual X-ray point sources for the purpose of constraining their nature and deriving their fractional contributions to the hard-band continuum and Fe K line emission of the GRXE. Based on the X-ray color-color diagram, we divided the point sources into three groups: A (hard), B (soft and broad spectrum), and C (soft and peaked spectrum). The group A sources are further decomposed spectrally into thermal and non-thermal sources with different fractions in different flux ranges. From their X-ray properties, we speculate that the group A non-thermal sources are mostly active galactic nuclei and the thermal sources are mostly white dwarf (WD) binaries such as magnetic and non-magnetic cataclysmic variables (CVs), pre-CVs, and symbiotic stars, whereas the group B and C sources are X-ray active stars in flares and quiescence, respectively. In the log N-log S curve of the 2-8 keV band, the group A non-thermal sources are dominant above Almost-Equal-To 10{sup -14} erg cm{sup -2} s{sup -1}, which is gradually taken over by Galactic sources in the fainter flux ranges. The Fe K{alpha} emission is mostly from the group A thermal (WD binaries) and the group B (X-ray active stars) sources.

  4. Observation of the Crab Nebula in Soft Gamma Rays with the Nuclear Compton Telescope

    E-Print Network [OSTI]

    Bandstra, Mark ShenYu

    2010-01-01T23:59:59.000Z

    Gamma-ray bursts . . . . . . . . . . . . . . . . . . . 1.268] G. J. Fishman. The gamma-ray burst capabilities of BATSEOlson. Observations of Gamma- Ray Bursts of Cosmic Origin.

  5. Beyond hard x-ray photoelectron spectroscopy: Simultaneous combination with x-ray diffraction

    SciTech Connect (OSTI)

    Rubio-Zuazo, Juan; Castro, German R. [SpLine, Spanish CRG beamline at the European Synchrotron Radiation Facility, B.P. 220, F-38043 Grenoble (France) and ICMM-CSIC Cantoblanco, E-28049 Madrid (Spain)

    2013-05-15T23:59:59.000Z

    Hard x-ray photoelectron spectroscopy (HAXPES) is a powerful and novel emerging technique for the nondestructive determination of electronic properties and chemical composition of bulk, buried interfaces and surfaces. It benefits from the exceptionally large escape depth of high kinetic energy photoelectrons, increasing the information depth up to several tens of nanometers. Complementing HAXPES with an atomic structure sensitive technique (such as x-ray diffraction) opens a new research field with major applications for materials science. At SpLine, the Spanish CRG beamline at the European Synchrotron Radiation Facility, we have developed a novel experimental set-up that combines HAXPES and x-ray diffraction (x-ray reflectivity, surface x-ray diffraction, grazing incidence x-ray diffraction, and reciprocal space maps). Both techniques can be operated simultaneously on the same sample and using the same excitation source. The set-up includes a robust 2S + 3D diffractometer hosting a ultrahigh vacuum chamber equipped with a unique photoelectron spectrometer (few eV < electron kinetic energy < 15 keV), x-ray tube (Mg/Ti), 15 keV electron gun, and auxiliary standard surface facilities (molecular beam epitaxy evaporator, ion gun, low energy electron diffraction, sample heating/cooling system, leak valves, load-lock sample transfer, etc.). This end-station offers the unique possibility of performing simultaneous HAXPES + x-ray diffraction studies. In the present work, we describe the experimental set-up together with two experimental examples that emphasize its outstanding capabilities: (i) nondestructive characterization of the Si/Ge and HfO{sub 2}/SiO{sub 2} interfaces on Ge-based CMOS devices, and (ii) strain study on La{sub 0.7}Ca{sub 0.3}MnO{sub 3} ultrathin films grown on SrTiO{sub 3}(001) substrate.

  6. A simple technique for gamma ray and cosmic ray spectroscopy using plastic scintillator

    E-Print Network [OSTI]

    Akhilesh P. Nandan; Sharmili Rudra; Himangshu Neog; S. Biswas; S. Mahapatra; B. Mohanty; P. K. Samal

    2015-04-10T23:59:59.000Z

    A new and simple technique has been developed using plastic scintillator detectors for gamma ray and cosmic ray spectroscopy without single channel analyzer (SCA) or multichannel analyzer (MCA). In these experiments only a leading edge discriminator (LED) and NIM scalers have been used. Energy calibration of gamma spectra in plastic scintillators has been done using Co$^{60}$ and Cs$^{137}$ sources. The details experimental technique, analysis procedure and experimental results has been presented in this article.

  7. A simple technique for gamma ray and cosmic ray spectroscopy using plastic scintillator

    E-Print Network [OSTI]

    Akhilesh P. Nandan; Sharmili Rudra; Himangshu Neog; S. Biswas; S. Mahapatra; B. Mohanty; P. K. Samal

    2014-12-30T23:59:59.000Z

    A new and simple technique has been developed using plastic scintillator detectors for gamma ray and cosmic ray spectroscopy without single channel analyzer (SCA) or multichannel analyzer (MCA). In these experiments only a leading edge discriminator (LED) and NIM scalers have been used. Energy calibration of gamma spectra in plastic scintillators has been done using Co$^{60}$ and Cs$^{137}$ sources. The details experimental technique, analysis procedure and experimental results has been presented in this article.

  8. PoGOLite -The Polarised Gamma-ray Observer

    E-Print Network [OSTI]

    Haviland, David

    PoGOLite - The Polarised Gamma-ray Observer CECILIA MARINI BETTOLO Licentiate Thesis Stockholm, Sweden 2008 #12;#12;Licentiate Thesis PoGOLite - The Polarised Gamma-ray Observer Cecilia Marini Bettolo

  9. A graphics architecture for ray tracing and photon mapping

    E-Print Network [OSTI]

    Ling, Junyi

    2005-11-01T23:59:59.000Z

    and spatial locality, as well as eliminating unnecessary random memory accesses. A high level abstraction of the combined ray tracing and photon mapping streaming pipeline is introduced. Based on this abstraction, an e?cient ray tracing and photon...

  10. Biological Imaging by Soft X-Ray Diffraction Microscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biological Imaging by Soft X-Ray Diffraction Microscopy Print Electron and x-ray microscopes are a valuable tool for both the life and materials sciences, but they are limited in...

  11. The X-ray Microcalorimeter Spectrometer onboard of IXO

    E-Print Network [OSTI]

    Figueroa-Feliciano, Enectali

    One of the instruments on the International X-ray Observatory (IXO), under study with NASA, ESA and JAXA, is the X-ray Microcalorimeter Spectrometer (XMS). This instrument, which will provide high spectral resolution images, ...

  12. Resonant Soft X-Ray Scattering - Combining Structural with Spectroscop...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Resonant Soft X-Ray Scattering - Combining Structural with Spectroscopic Refinement Friday, September 28, 2012 - 10:00am SLAC, Bldg. 137, Room 322 SSRL Presents Kevin Stone X-ray...

  13. The Animated Gamma-ray Sky Revealed by the Fermi Gamma-ray Space Telescope

    ScienceCinema (OSTI)

    Isabelle Grenier

    2010-01-08T23:59:59.000Z

    The Fermi Gamma-ray Space Telescope has been observing the sky in gamma-rays since August 2008. In addition to breakthrough capabilities in energy coverage (20 MeV-300 GeV) and angular resolution, the wide field of view of the Large Area Telescope enables observations of 20% of the sky at any instant, and of the whole sky every three hours. It has revealed a very animated sky with bright gamma-ray bursts flashing and vanishing in minutes, powerful active galactic nuclei flaring over hours and days, many pulsars twinkling in the Milky Way, and X-ray binaries shimmering along their orbit. Most of these variable sources had not been seen by the Fermi predecessor, EGRET, and the wealth of new data already brings important clues to the origin of the high-energy emission and particles powered by the compact objects. The telescope also brings crisp images of the bright gamma-ray emission produced by cosmic-ray interactions in the interstellar medium, thus allowing to measure the cosmic nuclei and electron spectra across the Galaxy, to weigh interstellar clouds, in particular in the dark-gas phase. The telescope sensitivity at high energy will soon provide useful constraints on dark-matter annihilations in a variety of environments. I will review the current results and future prospects of the Fermi mission.

  14. Ultra High Energy Cosmic Rays and Gamma Ray Bursts from Axion Stars

    E-Print Network [OSTI]

    Aiichi Iwazaki

    2000-08-29T23:59:59.000Z

    We propose a model in which ultra high energy cosmic rays and gamma ray bursts are produced by collisions between neutron stars and axion stars. The acceleration of such a cosmic ray is made by the electric field, $\\sim 10^{15} (B/10^{12} {G}) {eV} {cm}^{-1}$, which is induced in an axion star by relatively strong magnetic field $B>10^{12}$ G of a neutron star. On the other hand, similar collisions generate gamma ray bursts when magnetic field is relatively small, e.g. $\\leq 10^{10}$ G. Assuming that the axion mass is $\\sim 10^{-9}$ eV, we can explain huge energies of the gamma ray bursts $\\sim 10^{54}$ erg as well as the ultra high energies of the cosmic rays $\\sim 10^{20}$ eV. We estimate rate of energy release in the collisions and we find that the rate roughly agrees with observations. In addition, we show that these axion stars are plausible candidates for MACHOs. Since the axion star induces oscillating electric current under the magnetic field, observable monochromatic radiations are emitted.

  15. High Energy Gamma-Ray Emission from Gamma-Ray Bursts - Before GLAST

    SciTech Connect (OSTI)

    Fan, Yi-Zhong; Piran, Tsvi

    2011-11-29T23:59:59.000Z

    Gamma-ray bursts (GRBs) are short and intense emission of soft {gamma}-rays, which have fascinated astronomers and astrophysicists since their unexpected discovery in 1960s. The X-ray/optical/radio afterglow observations confirm the cosmological origin of GRBs, support the fireball model, and imply a long-activity of the central engine. The high-energy {gamma}-ray emission (> 20 MeV) from GRBs is particularly important because they shed some lights on the radiation mechanisms and can help us to constrain the physical processes giving rise to the early afterglows. In this work, we review observational and theoretical studies of the high-energy emission from GRBs. Special attention is given to the expected high-energy emission signatures accompanying the canonical early-time X-ray afterglow that was observed by the Swift X-ray Telescope. We also discuss the detection prospect of the upcoming GLAST satellite and the current ground-based Cerenkov detectors.

  16. Can Ultrahigh Energy Cosmic Rays Come from Gamma-Ray Bursts? II: Cosmic Rays Below the Ankle and Galactic GRB

    E-Print Network [OSTI]

    Eichler, David

    2011-01-01T23:59:59.000Z

    The maximum cosmic ray energy achievable by acceleration by a relativistic blast wave is derived. It is shown that forward shocks from long GRB in the interstellar medium are powerful enough to produce the Galactic cosmic-ray component up to the ankle at $4\\times 10^{18}$eV, as per an earlier suggestion (Levinson and Eichler, 1993). It is further argued that, were extragalactic long GRB responsible for the component {\\it above} the ankle as well, the contribution from an occasional Galactic GRB within the solar circle would yield more than the observational limits on the outward flux from the solar circle, unless intermittency and/or beaming causes the present-day contribution to be less than $10^{-3}$ times the time average, and difficulties with these avoidance scenarios are also noted.

  17. Applications of holography to x-ray imaging

    SciTech Connect (OSTI)

    Howells, M.; Iarocci, M.; Kenney, J.; Rarback, H.; Rosser, R.; Yun, W.

    1985-03-01T23:59:59.000Z

    In this paper we consider various applications of holographic techniques to the problem of soft x-ray imaging. We give special attention to imaging biological material using x-rays in the wavelength range 24 to 45A. We describe some experiments on formation and reconstruction of x-ray holograms and propose some ways in which holographic techniques might contribute to the difficult problem of fabricating optical elements for use in the soft x-ray region.

  18. Applications of holography to X-ray imaging

    SciTech Connect (OSTI)

    Howells, M.; Iarocci, M.; Kenney, J.; Rarback, H.; Rosser, R.; Yun, W.

    1985-01-01T23:59:59.000Z

    In this paper the authors consider various applications of holographic techniques to the problem of soft x-ray imaging. Special attention is given to imaging biological material using x-rays in the wavelength range 24-45A. The authors describe some experiments on formation and reconstruction of x-ray holograms and propose some ways in which holographic techniques might contribute to the difficult problem of fabricating optical elements for use in the soft x-ray region.

  19. High Efficiency of Gamma-Ray Bursts Revisited

    E-Print Network [OSTI]

    Y. C. Zou A; Z. G. Dai B

    2007-01-01T23:59:59.000Z

    efficiency of gamma-ray bursts by assuming that the ejecta from the central engine are equally massive and

  20. X-ray MicroCT Training Presentation

    E-Print Network [OSTI]

    X-ray MicroCT Training Presentation T. Fettah Kosar, PhD Center for Nanoscale Systems Harvard) Model: HMXST225 (max. 225 kV) #12;Overview 3 Introduction to X-ray imaging and Computed Tomography (CT) · What are X-rays and how do we generate and image them? · How do we magnify X-ray images and keep them

  1. Femtosecond laser-electron x-ray source

    DOE Patents [OSTI]

    Hartemann, Frederic V.; Baldis, Hector A.; Barty, Chris P.; Gibson, David J.; Rupp, Bernhard

    2004-04-20T23:59:59.000Z

    A femtosecond laser-electron X-ray source. A high-brightness relativistic electron injector produces an electron beam pulse train. A system accelerates the electron beam pulse train. The femtosecond laser-electron X-ray source includes a high intra-cavity power, mode-locked laser and an x-ray optics system.

  2. Initial conditions for paraxial ray tracing in inhomogeneous anisotropic media

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    , theoretical seismology, seismic anisotropy, wave propagation 1 Introduction By standard kinematic ray tracing and in numerical modelling and interpretation of high-frequency seismic wave #12;elds propagating in inhomogeneous to such important quantities as geometrical spreading and ray amplitudes. The limitations of kinematic ray tracing

  3. Gamma-ray Sky Observed with Fermi Large Area Telescope

    E-Print Network [OSTI]

    Yamamoto, Hirosuke

    detection reported Flare activity reported via ATel Gamma Ray Bursts reported via GCN Giant MC imageGamma-ray Sky Observed with Fermi Large Area Telescope RESCEU Symposium on Astroparticle Physics) Measure the photon direction Identification of the gamma-ray shower 36 planes of Si strip detectors (228 m

  4. The Biggest Bangs The Mystery of Gamma-Ray Bursts,

    E-Print Network [OSTI]

    Katz, Jonathan I.

    The Biggest Bangs The Mystery of Gamma-Ray Bursts, The Most Violent Explosions in The Universe J. I. Did a Gamma-Ray Burst Kill the Dinosaurs? Will a Burst Kill Us? #15; Glossary #15; Sources #15; Index. On January 23, 1999, one of these four cameras recorded visible light from a gamma-ray burst

  5. The Biggest Bangs The Mystery of Gamma-Ray Bursts,

    E-Print Network [OSTI]

    Katz, Jonathan I.

    The Biggest Bangs The Mystery of Gamma-Ray Bursts, The Most Violent Explosions in The Universe J. I a Gamma-Ray Burst Kill the Dinosaurs? Will a Burst Kill Us? · Glossary · Sources · Index viii #12;Chapter of these four cameras recorded visible light from a gamma-ray burst as it was happening, which had been the holy

  6. Gamma-Ray Bursts Nuclear Test Ban Treaty, 1963

    E-Print Network [OSTI]

    Harrison, Thomas

    Lecture 18 Gamma-Ray Bursts #12;Nuclear Test Ban Treaty, 1963 First Vela satellite pair launched and their predecessors, Vela 4, discovered the first gamma-ray bursts. The discovery was announced by Klebesadel, Strong, and Olson (ApJ, 182, 85) in 1973. #12;First Gamma-Ray Burst The Vela 5 satellites functioned from July, 1969

  7. X-ray Diffraction Laboratory Department of Chemistry

    E-Print Network [OSTI]

    Meagher, Mary

    X-ray Diffraction Laboratory Department of Chemistry Texas A & M University College Station, Texas Phone : 979-845-9125 www.chem.tamu.edu/xray xray@tamu.edu X-rayDiffractionLaboratory DepartmentofChemistry 3255TAMU CollegeStation,TX77843-3255 Mission The purpose of our laboratory is to provide X-ray

  8. X-ray Diffraction Practicals 1 Graphics Programs

    E-Print Network [OSTI]

    Meagher, Mary

    X-ray Diffraction Practicals 1 Graphics Programs that will read SHELX or CIF files J. Reibenspies, N. Bhuvanesh ver 1.0.0 #12;X-ray Diffraction Practicals 2 Free software. Gretep : Reads SHELX files shelx files or output thermal ellipsoid plots. http://www.umass.edu/microbio/rasmol/ #12;X-ray

  9. X-ray Emission from Massive Stars David Cohen

    E-Print Network [OSTI]

    Cohen, David

    X-ray Emission from Massive Stars David Cohen Department of Physics and Astronomy Swarthmore University, Oct. 13, 2005 astro.swarthmore.edu/~cohen/ #12;Outline 1. What you need to know: a. X-rays from the Sun - magnetic activity, x-ray spectra b. Hot stars c. Radiation-driven winds and the Doppler shift d

  10. X-Ray Photoelectron Spectroscopy XPS Mark Engelhard

    E-Print Network [OSTI]

    X-Ray Photoelectron Spectroscopy XPS Mark Engelhard 1 #12;EMSL XPS Instrumentation 2 Physical Electronics Quantera XPS High Energy Resolution Focused X-ray Beam Capability Catalysis reaction and processing chamber with inert atmosphere glove box connected to a PHI Quantera Scanning X-ray Microprobe

  11. SUMMER 2014 SEMESTER CLASS SCHEDULE Tuesday, May 20, through Tuesday, August 12, 2014

    E-Print Network [OSTI]

    Gilchrist, James F.

    ) The following courses offered by Lehigh University's Graduate College of Education afford professional leaders in the field of education an opportunity to advance in the subject areas of their special interest. Lehigh ­­­­­­ IMPORTANT: if you are looking at a printed copy, updates are located on our website coe

  12. SUMMER 2014 SEMESTER CLASS SCHEDULE Tuesday, May 20, through Tuesday, August 12, 2014

    E-Print Network [OSTI]

    Gilchrist, James F.

    ) The following courses offered by Lehigh University's Graduate College of Education afford professional leaders in the field of education an opportunity to advance in the subject areas of their special interest. Lehigh 10, 2014 ­­­­­­ IMPORTANT: if you are looking at a printed copy, updates are located on our website

  13. Real time gamma-ray signature identifier

    DOE Patents [OSTI]

    Rowland, Mark (Alamo, CA); Gosnell, Tom B. (Moraga, CA); Ham, Cheryl (Livermore, CA); Perkins, Dwight (Livermore, CA); Wong, James (Dublin, CA)

    2012-05-15T23:59:59.000Z

    A real time gamma-ray signature/source identification method and system using principal components analysis (PCA) for transforming and substantially reducing one or more comprehensive spectral libraries of nuclear materials types and configurations into a corresponding concise representation/signature(s) representing and indexing each individual predetermined spectrum in principal component (PC) space, wherein an unknown gamma-ray signature may be compared against the representative signature to find a match or at least characterize the unknown signature from among all the entries in the library with a single regression or simple projection into the PC space, so as to substantially reduce processing time and computing resources and enable real-time characterization and/or identification.

  14. The Pierre Auger Cosmic Ray Observatory

    E-Print Network [OSTI]

    ,

    2015-01-01T23:59:59.000Z

    The Pierre Auger Observatory, located on a vast, high plain in western Argentina, is the world's largest cosmic ray observatory. The objectives of the Observatory are to probe the origin and characteristics of cosmic rays above $10^{17}$ eV and to study the interactions of these, the most energetic particles observed in nature. The Auger design features an array of 1660 water-Cherenkov particle detector stations spread over 3000 km$^2$ overlooked by 24 air fluorescence telescopes. In addition, three high elevation fluorescence telescopes overlook a 23.5 km$^2$, 61 detector infill array. The Observatory has been in successful operation since completion in 2008 and has recorded data from an exposure exceeding 40,000 km$^2$ sr yr. This paper describes the design and performance of the detectors, related subsystems and infrastructure that make up the Auger Observatory.

  15. High resolution x-ray microscope

    SciTech Connect (OSTI)

    Gary, C. K.; Park, H.; Lombardo, L. W.; Piestrup, M. A.; Cremer, J. T.; Pantell, R. H.; Dudchik, Y. I. [Adelphi Technology, Inc. 981-B Industrial Road, San Carlos, California 94070 (United States); Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Institute of Applied Physics Problems, Kurchatova 7, Minsk 220064 (Belarus)

    2007-04-30T23:59:59.000Z

    The authors present x-ray images of grid meshes and biological material obtained using a microspot x-ray tube with a multilayer optic and a 92-element parabolic compound refractive lens (CRL) made of a plastic containing only hydrogen and carbon. Images obtained using this apparatus are compared with those using an area source with a spherical lens and a spherical lens with multilayer condenser. The authors found the best image quality using the multilayer condenser with a parabolic lens, compared to images with a spherical lens and without the multilayer optics. The resolution was measured using a 155-element parabolic CRL and a multilayer condenser with the microspot tube. The experiment demonstrates about 1.1 {mu}m resolution.

  16. Phenomenology of Gamma-Ray Jets

    E-Print Network [OSTI]

    Amir Levinson

    2007-09-10T23:59:59.000Z

    We discuss some phenomenological aspects of $\\gamma$-ray emitting jets. In particular, we present calculations of the $\\gamma$-sphere and $\\pi$-sphere for various target photon fields, and employ them to demonstrate how $\\gamma$-ray observations at very high energies can be used to constraint the Doppler factor of the emitting plasma and the production of VHE neutrinos. We also consider the implications of the rapid TeV variability observed in M87 and the TeV blazars, and propose a model for the very rapid TeV flares observed with HESS and MAGIC in some blazars,that accommodates the relatively small Doppler factors inferred from radio observations. Finally, we briefly discuss the prospects for detecting VHE neutrinos from relativistic jets.

  17. Neutron-driven gamma-ray laser

    DOE Patents [OSTI]

    Bowman, Charles D. (Los Alamos, NM)

    1990-01-01T23:59:59.000Z

    A lasing cylinder emits laser radiation at a gamma-ray wavelength of 0.87 .ANG. when subjected to an intense neutron flux of about 400 eV neutrons. A 250 .ANG. thick layer of Be is provided between two layers of 100 .ANG. thick layer of .sup.57 Co and these layers are supported on a foil substrate. The coated foil is coiled to form the lasing cylinder. Under the neutron flux .sup.57 Co becomes .sup.58 Co by neutron absorption. The .sup.58 Co then decays to .sup.57 Fe by 1.6 MeV proton emission. .sup.57 Fe then transitions by mesne decay to a population inversion for lasing action at 14.4 keV. Recoil from the proton emission separates the .sup.57 Fe from the .sup.57 Co and into the Be, where Mossbauer emission occurs at a gamma-ray wavelength.

  18. X-ray radiography for container inspection

    DOE Patents [OSTI]

    Katz, Jonathan I. (Clayton, MO); Morris, Christopher L. (Los Alamos, NM)

    2011-06-07T23:59:59.000Z

    Arrangements of X-ray inspection systems are described for inspecting high-z materials in voluminous objects such as containers. Inspection methods may involve generating a radiographic image based on detected attenuation corresponding to a pulsed beams of radiation transmitted through a voluminous object. The pulsed beams of radiation are generated by a high-energy source and transmitted substantially downward along an incident angle, of approximately 1.degree. to 30.degree., to a vertical axis extending through the voluminous object. The generated radiographic image may be analyzed to detect on localized high attenuation representative of high-z materials and to discriminate high-z materials from lower and intermediate-z materials on the basis of the high density and greater attenuation of high-z material for higher energy (3-10 MeV) X-rays, and the compact nature of threatening masses of fissionable materials.

  19. Fissile interrogation using gamma rays from oxygen

    DOE Patents [OSTI]

    Smith, Donald; Micklich, Bradley J.; Fessler, Andreas

    2004-04-20T23:59:59.000Z

    The subject apparatus provides a means to identify the presence of fissionable material or other nuclear material contained within an item to be tested. The system employs a portable accelerator to accelerate and direct protons to a fluorine-compound target. The interaction of the protons with the fluorine-compound target produces gamma rays which are directed at the item to be tested. If the item to be tested contains either a fissionable material or other nuclear material the interaction of the gamma rays with the material contained within the test item with result in the production of neutrons. A system of neutron detectors is positioned to intercept any neutrons generated by the test item. The results from the neutron detectors are analyzed to determine the presence of a fissionable material or other nuclear material.

  20. Lorentz violation from gamma-ray bursts

    E-Print Network [OSTI]

    Shu Zhang; Bo-Qiang Ma

    2014-06-18T23:59:59.000Z

    The constancy of light speed is a basic assumption in Einstein's special relativity, and consequently the Lorentz invariance is a fundamental symmetry of space-time in modern physics. However, it is speculated that the speed of light becomes energy-dependent due to the Lorentz invariance violation~(LV) in various new physics theories. We analyse the data of the energetic photons from the gamma-ray bursts (GRBs) by the Fermi Gamma-Ray Space Telescope, and find more events to support the energy dependence in the light speed with both linear and quadratic form corrections. We provide two scenarios to understand all the new-released Pass~8 data of bright GRBs by the Fermi-LAT Collaboration, with predictions from such scenarios being testable by future detected GRBs.

  1. Sample holder for X-ray diffractometry

    DOE Patents [OSTI]

    Hesch, Victor L. (Los Alamos, NM)

    1992-01-01T23:59:59.000Z

    A sample holder for use with X-ray diffractometers with the capability to rotate the sample, as well as to adjust the position of the sample in the x, y, and z directions. Adjustment in the x direction is accomplished through loosening set screws, moving a platform, and retightening the set screws. Motion translators are used for adjustment in the y and z directions. An electric motor rotates the sample, and receives power from the diffractometer.

  2. Columbia University X-Ray Measurements

    E-Print Network [OSTI]

    V-720 keV · NaI 2x2x2" detector views an energy range of 1 keV-3 MeV Store signal in the tree. computer configuration. Plasmas were created using multi-frequency ECRH, and we find that most of the plasma energy is stored in the fast electrons. The energy spectrum of the x-ray emission below 740 keV is measured

  3. Gamma-Ray Line Observations with RHESSI

    E-Print Network [OSTI]

    David M. Smith

    2004-04-30T23:59:59.000Z

    The Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) has been observing gamma-ray lines from the Sun and the Galaxy since its launch in February 2002. Here I summarize the status of RHESSI observations of solar lines (nuclear de-excitation, neutron capture, and positron annihilation), the lines of $^{26}$Al and $^{60}$Fe from the inner Galaxy, and the search for positron annihilation in novae.

  4. Phenomenology of cosmic ray air showers

    E-Print Network [OSTI]

    M. T. Dova

    2005-05-30T23:59:59.000Z

    The properties of cosmic rays with energies above 1PeV have to be deduced from the spacetime structure and particle content of the air showers which they initiate. In this review, a summary of the phenomenology of these giant air showers is presented. We describe the hadronic interaction models used to extrapolate results from collider data to ultra high energies, an also the main electromagnetic processes that govern the longitudinal shower evolution as well as the lateral spread of particles.

  5. X-rays from Supernova Remnants

    E-Print Network [OSTI]

    B. Aschenbach

    2002-08-28T23:59:59.000Z

    A summary of X-ray observations of supernova remnants is presented including the explosion fragment A of the Vela SNR, Tycho, N132D, RX J0852-4622, the Crab Nebula and the 'bulls eye', and SN 1987A, high-lighting the progress made with Chandra and XMM-Newton and touching upon the questions which arise from these observations and which might inspire future research.

  6. Solar panels as cosmic-ray detectors

    E-Print Network [OSTI]

    Stella, Carlo; Assis, Pedro; Brogueira, Pedro; Santo, Catarina Espirito; Goncalves, Patricia; Pimenta, Mario; De Angelis, Alessandro

    2014-01-01T23:59:59.000Z

    Due to fundamental limitations of accelerators, only cosmic rays can give access to centre-of- mass energies more than one order of magnitude above those reached at the LHC. In fact, extreme energy cosmic rays (1018 eV - 1020 eV) are the only possibility to explore the 100 TeV energy scale in the years to come. This leap by one order of magnitude gives a unique way to open new horizons: new families of particles, new physics scales, in-depth investigations of the Lorentz symmetries. However, the flux of cosmic rays decreases rapidly, being less than one particle per square kilometer per year above 1019 eV: one needs to sample large surfaces. A way to develop large-effective area, low cost, detectors, is to build a solar panel-based device which can be used in parallel for power generation and Cherenkov light detection. Using solar panels for Cherenkov light detection would combine power generation and a non-standard detection device.

  7. X-ray Free-electron Lasers

    SciTech Connect (OSTI)

    Feldhaus, J.; /DESY; Arthur, J.; Hastings, J.B.; /SLAC

    2007-02-23T23:59:59.000Z

    In a free-electron laser (FEL) the lasing medium is a high-energy beam of electrons flying with relativistic speed through a periodic magnetic field. The interaction between the synchrotron radiation that is produced and the electrons in the beam induces a periodic bunching of the electrons, greatly increasing the intensity of radiation produced at a particular wavelength. Depending only on a phase match between the electron energy and the magnetic period, the wavelength of the FEL radiation can be continuously tuned within a wide spectral range. The FEL concept can be adapted to produce radiation wavelengths from millimeters to Angstroms, and can in principle produce hard x-ray beams with unprecedented peak brightness, exceeding that of the brightest synchrotron source by ten orders of magnitude or more. This paper focuses on short-wavelength FELs. It reviews the physics and characteristic properties of single-pass FELs, as well as current technical developments aiming for fully coherent x-ray radiation pulses with pulse durations in the 100 fs to 100 as range. First experimental results at wavelengths around 100 nm and examples of scientific applications planned on the new, emerging x-ray FEL facilities are presented.

  8. Solution To The Gamma Ray Burst Mystery?

    E-Print Network [OSTI]

    Nir J. Shaviv; Arnon Dar

    1996-08-21T23:59:59.000Z

    Photoexcitation and ionization of partially ionized heavy atoms in highly relativistic flows by interstellar photons, followed by their reemission in radiative recombination and decay, boost star-light into beamed $\\gamma$ rays along the flow direction. Repeated excitation/decay of highly relativistic baryonic ejecta from merger or accretion induced collapse of neutron stars in dense stellar regions (DSRs), like galactic cores, globular clusters and super star-clusters, can convert enough kinetic energy in such events in distant galaxies into cosmological gamma ray bursts (GRBs). The model predicts remarkably well all the main observed temporal and spectral properties of GRBs. Its success strongly suggests that GRBs are $\\gamma$ ray tomography pictures of DSRs in galaxies at cosmological distances with unprecedented resolution: A time resolution of $dt\\sim 1~ms$ in a GRB can resolve stars at a Hubble distance which are separated by only $D\\sim 10^{10}cm$. This is equivalent to the resolving power of an optical telescope with a diameter larger than one Astronomical Unit!

  9. The Galactic gamma-ray club

    E-Print Network [OSTI]

    Isabelle A. Grenier

    2008-04-02T23:59:59.000Z

    The exclusive Galactic gamma-ray club has opened up to new members. Supernova remnants, pulsar wind nebulae, and massive binary systems hosting a compact object have recently joined the young pulsars as firmly established sources of gamma rays in the Milky Way. Massive young stellar clusters are on the waiting list to join the club. Only the fine imaging recently obtained at TeV energies could resolve specific sources. The samples are sparse, but raise exciting questions. The jet or pulsar-wind origin of the emission in binaries has been hotly debated, but it seems that both types of systems have been recently detected. The nature of the radiation in shock accelerators is still questioned: do nuclei contribute a lot, a little, or not to the gamma rays and what energy do they carry away from the shock budget? The acceleration process and the structural evolution of the pulsar winds are still uncertain. The magnetic field distribution in all these systems is a key, but poorly constrained, ingredient to model the multi-wavelength data, particle transport and electron ageing. It must, however, be determined in order to efficiently probe particle distributions and the acceleration mechanisms. The source samples soon to be expected from GLAST and the Cherenkov telescopes should bring new valuable test cases and they will, for the first time, shed statistical light on the collective behaviour of these different types of accelerators.

  10. The X-ray Telescope of CAST

    E-Print Network [OSTI]

    M. Kuster; H. Bruninger; S. Cbrian; M. Davenport; C. Elefteriadis; J. Englhauser; H. Fischer; J. Franz; P. Friedrich; R. Hartmann; F. H. Heinsius; D. H. H. Hoffmann; G. Hoffmeister; J. N. Joux; D. Kang; K. Knigsmann; R. Kotthaus; T. Papaevangelou; C. Lasseur; A. Lippitsch; G. Lutz; J. Morales; A. Rodrguez; L. Strder; J. Vogel; K. Zioutas

    2007-05-10T23:59:59.000Z

    The Cern Axion Solar Telescope (CAST) is in operation and taking data since 2003. The main objective of the CAST experiment is to search for a hypothetical pseudoscalar boson, the axion, which might be produced in the core of the sun. The basic physics process CAST is based on is the time inverted Primakoff effect, by which an axion can be converted into a detectable photon in an external electromagnetic field. The resulting X-ray photons are expected to be thermally distributed between 1 and 7 keV. The most sensitive detector system of CAST is a pn-CCD detector combined with a Wolter I type X-ray mirror system. With the X-ray telescope of CAST a background reduction of more than 2 orders off magnitude is achieved, such that for the first time the axion photon coupling constant g_agg can be probed beyond the best astrophysical constraints g_agg < 1 x 10^-10 GeV^-1.

  11. X-Ray Searches for Solar Axions

    E-Print Network [OSTI]

    Hugh S. Hudson; L. W. Acton; E. DeLuca; I. G. Hannah; K. Reardon; K. Van Bibber

    2012-01-22T23:59:59.000Z

    Axions generated thermally in the solar core can convert nearly directly to X-rays as they pass through the solar atmosphere via interaction with the magnetic field. The result of this conversion process would be a diffuse centrally-concentrated source of few-keV X-rays at disk center; it would have a known dimension, of order 10% of the solar diameter, and a spectral distribution resembling the blackbody spectrum of the solar core. Its spatial structure in detail would depend on the distribution of mass and field in the solar atmosphere. The brightness of the source depends upon these factors as well as the unknown coupling constant and the unknown mass of the axion; this particle is hypothetical and no firm evidence for its existence has been found yet. We describe the solar magnetic environment as an axion/photon converter and discuss the upper limits obtained by existing and dedicated observations from three solar X-ray observatories: Yohkoh, RHESSI, and Hinode

  12. Compton Recoil Electron Tracking With the TIGRE Gamma-Ray Balloon Experiment

    E-Print Network [OSTI]

    Kamiya, Kaoru

    2011-01-01T23:59:59.000Z

    AGNs), pulsars, gamma-ray bursts, cosmic ray interactionssensitive to cosmic gamma-ray bursts in the energy range ofGalactic center, a single gamma-ray burst which occurred 10

  13. E-Print Network 3.0 - airborne lead x-ray Sample Search Results

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Pulsars... you'd . . . Active Galactic . . . X-ray binaries Pulsars and relatives Gamma-ray bursts Gravitational... 1 - Type 2 X-ray binaries - Low mass X-ray binaries (LMXBs)...

  14. E-Print Network 3.0 - attosecond kev x-ray Sample Search Results

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    de Montral Collection: Engineering 3 Generation of Attosecond X-ray and gamma-ray via Compton backscattering Summary: Generation of Attosecond X-ray and gamma-ray via...

  15. Calibrating X-ray Imaging Devices for Accurate Intensity Measurement

    SciTech Connect (OSTI)

    Haugh, M. J.

    2011-07-28T23:59:59.000Z

    The purpose of the project presented is to develop methods to accurately calibrate X-ray imaging devices. The approach was to develop X-ray source systems suitable for this endeavor and to develop methods to calibrate solid state detectors to measure source intensity. NSTec X-ray sources used for the absolute calibration of cameras are described, as well as the method of calibrating the source by calibrating the detectors. The work resulted in calibration measurements for several types of X-ray cameras. X-ray camera calibration measured efficiency and efficiency variation over the CCD. Camera types calibrated include: CCD, CID, back thinned (back illuminated), front illuminated.

  16. Proceedings of the workshop on X-ray computed microtomography

    SciTech Connect (OSTI)

    NONE

    1998-02-01T23:59:59.000Z

    This report consists of vugraphs from the nine presentations at the conference. Titles of the presentations are: CMT: Applications and Techniques; Computer Microtomography Using X-rays from Third Generation Synchrotron X-ray; Approaches to Soft-X-ray Nanotomography; Diffraction Enhanced Tomography; X-ray Computed Microtomography Applications at the NSLS; XCMT Applications in Forestry and Forest Products; 3DMA: Investigating Three Dimensional Pore Geometry from High Resolution Images; X-ray Computed Microtomography Studies of Volcanic Rock; and 3-D Visualization of Tomographic Volumes.

  17. Apparatus for monitoring X-ray beam alignment

    DOE Patents [OSTI]

    Steinmeyer, P.A.

    1991-10-08T23:59:59.000Z

    A self-contained, hand-held apparatus is provided for monitoring alignment of an X-ray beam in an instrument employing an X-ray source. The apparatus includes a transducer assembly containing a photoresistor for providing a range of electrical signals responsive to a range of X-ray beam intensities from the X-ray beam being aligned. A circuit, powered by a 7.5 VDC power supply and containing an audio frequency pulse generator whose frequency varies with the resistance of the photoresistor, is provided for generating a range of audible sounds. A portion of the audible range corresponds to low X-ray beam intensity. Another portion of the audible range corresponds to high X-ray beam intensity. The transducer assembly may include an a photoresistor, a thin layer of X-ray fluorescent material, and a filter layer transparent to X-rays but opaque to visible light. X-rays from the beam undergoing alignment penetrate the filter layer and excite the layer of fluorescent material. The light emitted from the fluorescent material alters the resistance of the photoresistor which is in the electrical circuit including the audio pulse generator and a speaker. In employing the apparatus, the X-ray beam is aligned to a complete alignment by adjusting the X-ray beam to produce an audible sound of the maximum frequency. 2 figures.

  18. Apparatus for monitoring X-ray beam alignment

    DOE Patents [OSTI]

    Steinmeyer, Peter A. (Arvada, CO)

    1991-10-08T23:59:59.000Z

    A self-contained, hand-held apparatus is provided for minitoring alignment of an X-ray beam in an instrument employing an X-ray source. The apparatus includes a transducer assembly containing a photoresistor for providing a range of electrical signals responsive to a range of X-ray beam intensities from the X-ray beam being aligned. A circuit, powered by a 7.5 VDC power supply and containing an audio frequency pulse generator whose frequency varies with the resistance of the photoresistor, is provided for generating a range of audible sounds. A portion of the audible range corresponds to low X-ray beam intensity. Another portion of the audible range corresponds to high X-ray beam intensity. The transducer assembly may include an a photoresistor, a thin layer of X-ray fluorescent material, and a filter layer transparent to X-rays but opaque to visible light. X-rays from the beam undergoing alignment penetrate the filter layer and excite the layer of fluorescent material. The light emitted from the fluorescent material alters the resistance of the photoresistor which is in the electrical circuit including the audio pulse generator and a speaker. In employing the apparatus, the X-ray beam is aligned to a complete alignment by adjusting the X-ray beam to produce an audible sound of the maximum frequency.

  19. Quantitative x-ray imager (abstract)

    SciTech Connect (OSTI)

    Evans, Scott C.; Archuleta, Tom N.; Oertel, John A.; Walsh, Peter J.

    2001-01-01T23:59:59.000Z

    We report on development of a quantitative x-ray imager (QXI) for the national Inertial Confinement Fusion Program. Included in this development is a study of photocathode response as a function of photon energy, 2--17.5 keV, which is related to diagnostic development on the National Ignition Facility (NIF). The QXI is defined as being a quantative imager due to the repeated characterization. This instrument is systematically checked out, electronically as well as its photocathode x-ray response, both on a direct current and pulsed x-ray sources, before and after its use on a shot campaign. The QXI is a gated x-ray imager1 used for a variety of experiments conducted in the Inertial Confinement Fusion and Radiation Physics Program. The camera was assembled in Los Alamos and has been under development since 1997 and has now become the workhorse framing camera by the program. The electronics were built by Grant Applied Physics of San Fransisco, CA.2 The QXI has been used at the LANL Trident, LLNL Nova, and University of Rochester Laboratory OMEGA laser facilities. The camera consists of a grated microchannel plate (MCP), a phosphor coated fiberoptic faceplate coupled to film for data readout, along with high speed electronic pulsers to drive the x-ray detector. The QXI has both a two-strip and a four-strip detection head and has the ability to individually bias the gain of each of the strips. The timing of the QXI was done at the Trident short pulse laboratory, using 211 nm light. Single strip jitter was looked at as well and determined to be <25 ps. Flatfielding of the photocathode across the MCP was done with the Trident main laser with 150 J on a gold disk with a 1 ns. Spatial resolution was determined to be <5 {mu}m by using the same laser conditions as before and a backlit 1000 lp/in. grid. The QXI has been used on cylindrical implosion work at the Nova Laser Facility, and on direct-drive cylinder mix and indirect-drive high convergence implosion experiments at OMEGA. Its two-strip module has provided the capability to look at point backlighters, as part of technique development for experiments on the NIF. Its next use will be in March 2000 with its off axis viewer nose at Omega, providing a perpendicular view of Rayleigh--Taylor spike dissipation.

  20. 'Jet breaks' and 'missing breaks' in the X-Ray afterglow of Gamma Ray Bursts

    E-Print Network [OSTI]

    Dado, Shlomo; De Rjula, Alvaro

    2008-01-01T23:59:59.000Z

    The X-ray afterglows (AGs) of Gamma-Ray Bursts (GRBs) and X-Ray Flashes (XRFs) have, after the fast decline phase of their prompt emission, a temporal behaviour varying between two extremes. A large fraction of these AGs has a 'canonical' light curve which, after an initial shallow-decay 'plateau' phase, 'breaks smoothly' into a fast power-law decline. Very energetic GRBs, contrariwise, appear not to have a 'break', their AG declines like a power-law from the start of the observations. Breaks and 'missing breaks' are intimately related to the geometry and deceleration of the jets responsible for GRBs. In the frame of the 'cannonball' (CB) model of GRBs and XRFs, we analyze the cited extreme behaviours (canonical and pure power-law) and intermediate cases spanning the observed range of X-ray AG shapes. We show that the entire panoply of X-ray light-curve shapes --measured with Swift and other satellites-- are as anticipated, on very limpid grounds, by the CB model. We test the expected correlations between the...

  1. The cosmic X-ray and gamma-ray background from dark matter annihilation

    E-Print Network [OSTI]

    Zavala, Jesus; Slatyer, Tracy R; Loeb, Abraham; Springel, Volker

    2011-01-01T23:59:59.000Z

    (Abridged) The extragalactic background light (EBL) observed at multiple wavelengths is a promising tool to probe the nature of dark matter since it might contain a significant contribution from gamma-rays produced promptly by dark matter annihilation. Additionally, the electrons and positrons produced in the annihilation give energy to the CMB photons to populate the EBL with X-rays and gamma-rays. We here create full-sky maps of the radiation from both of these contributions using the high-resolution Millennium-II simulation. We use upper limits on the contributions of unknown sources to the EBL to constrain the intrinsic properties of dark matter using a model-independent approach that can be employed as a template to test different particle physics models (including those with a Sommerfeld enhancement). These upper limits are based on observations spanning eight orders of magnitude in energy (from soft X-rays measured by CHANDRA to gamma-rays measured by Fermi), and on expectations for the contributions f...

  2. A Link between Prompt Optical and Prompt Gamma-Ray Emission in Gamma-Ray Bursts

    E-Print Network [OSTI]

    W. T. Vestrand; P. R. Wozniak; J. A. Wren; E. E. Fenimore; T. Sakamoto; R. R. White; D. Casperson; H. Davis; S. Evans; M. Galassi; K. E. McGowan; J. A. Schier; J. W. Asa; S. D. Barthelmy; J. R. Cummings; N. Gehrels; D. Hullinger; H. A. Krimm; C. B. Markwardt; K. McLean; D. Palmer; A. Parsons; J. Tueller

    2005-04-05T23:59:59.000Z

    The prompt optical emission that arrives with gamma-rays from a cosmic gamma-ray burst (GRB) is a signature of the engine powering the burst, the properties of the ultra-relativistic ejecta of the explosion, and the ejecta's interactions with the surroundings. Until now, only GRB 990123 had been detected at optical wavelengths during the burst phase. Its prompt optical emission was variable and uncorrelated with the prompt gamma-ray emission, suggesting that the optical emission was generated by a reverse shock arising from the ejecta's collision with the surrounding material. Here we report prompt optical emission from GRB 041219a. It is variable and correlated with the prompt gamma-rays, indicating a common origin for the optical light and the gamma-rays. Within the context of the standard fireball model of GRBs, we attribute this new optical component to internal shocks driven into the burst ejecta by variations of the inner engine. The correlated optical emission is a direct probe of the jet isolated from the medium. The timing of the uncorrelated optical emission is strongly dependent on the nature of the medium.

  3. X-Ray Interactions with Matter from the Center for X-Ray Optics (CXRO)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Henke, B.L.; Gullikson, E.M.; Davis, J.C.

    The primary interactions of low-energy x-rays within condensed matter, viz. photoabsorption and coherent scattering, are described for photon energies outside the absorption threshold regions by using atomic scattering factors. The atomic scattering factors may be accurately determined from the atomic photoabsorption cross sections using modified Kramers-Kronig dispersion relations. From a synthesis of the currently available experimental data and recent theoretical calculations for photoabsorption, the angle-independent, forward-scattering components of the atomic scattering factors have been thus semiempirically determined and tabulated here for 92 elements and for the region 50-30,000 eV. Atomic scattering factors for all angles of coherent scattering and at the higher photon energies are obtained from these tabulated forward-scattering values by adding a simple angle-dependent form-factor correction. The incoherent scattering contributions that become significant for the light elements at the higher photon energies are similarly determined. The basic x-ray interaction relations that are used in applied x-ray physics are presented here in terms of the atomic scattering factors. The bulk optical constants are also related to the atomic scattering factors. These atomic and optical relations are applied to the detailed calculation of the reflectivity characteristics of a series of practical x-ray mirror, multilayer, and crystal monochromators. Comparisons of the results of this semiempirical,"atom-like", description of x-ray interactions for the low-energy region with those of experiment and ab initio theory are presented.

  4. TeV Burst of Gamma-Ray Bursts and Ultra High Energy Cosmic Rays

    E-Print Network [OSTI]

    Tomonori Totani

    1998-11-25T23:59:59.000Z

    Some recent experiments detecting very high energy (VHE) gamma-rays above 10-20 TeV independently reported VHE bursts for some of bright gamma-ray bursts (GRBs). If these signals are truly from GRBs, these GRBs must emit a much larger amount of energy as VHE gamma-rays than in the ordinary photon energy range of GRBs (keV-MeV). We show that such extreme phenomena can be reasonably explained by synchrotron radiation of protons accelerated to \\sim 10^{20-21} eV, which has been predicted by Totani (1998a). Protons seem to carry about (m_p/m_e) times larger energy than electrons, and hence the total energy liberated by one GRB becomes as large as \\sim 10^{56} (\\Delta \\Omega / 4 \\pi) ergs. Therefore a strong beaming of GRB emission is highly likely. Extension of the VHE spectrum beyond 20 TeV gives a nearly model-independent lower limit of the Lorentz factor of GRBs, as $\\gamma \\gtilde 500$. Furthermore, our model gives the correct energy range and time variability of ordinary keV-MeV gamma-rays of GRBs by synchrotron radiation of electrons. Therefore the VHE bursts of GRBs strongly support the hypothesis that ultra high energy cosmic rays observed on the Earth are produced by GRBs.

  5. Neutrinos from gamma-ray bursts: propagation of cosmic rays in their host galaxies

    E-Print Network [OSTI]

    Wang, Zi-Yi; Wang, Jun-Feng

    2015-01-01T23:59:59.000Z

    Gamma-ray bursts (GRBs) are proposed as candidate sources of ultra-high energy cosmic rays (UHECRs). We study the possibility that the PeV neutrinos recently observed by IceCube are produced by GRB cosmic rays interacting with the interstellar gas in the host galaxies. By studying the relation between the X-ray absorption column density N_H and the surface star-formation rate of GRB host galaxies, we find that N_H is a good indicator of the surface gas density of the host galaxies. Then we are able to calculate the neutrino production efficiency of CRs for GRBs with known N_H. We collect a sample of GRBs that have both measurements of N_H and accurate gamma-ray fluence, and attempt to calculate the accumulated neutrino flux based on the current knowledge about GRBs and their host galaxies. When the CR intensity produced by GRBs is normalized with the observed UHECR flux above $10^{19}{\\rm eV}$, the accumulated neutrino flux at PeV energies is estimated to be about $(0.3\\pm0.2)\\times10^{-8} \\rm{GeV\\ cm^{-2}\\ s...

  6. SUPERORBITAL MODULATION OF X-RAY EMISSION FROM GAMMA-RAY BINARY LSI +61 303

    SciTech Connect (OSTI)

    Chernyakova, M. [School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9 (Ireland); Neronov, A. [ISDC Data Center for Astrophysics, Chemin d'Ecogia 16, 1290 Versoix (Switzerland); Molkov, S.; Lutovinov, A. [Space Research Institute (IKI), 84/32 Profsoyuznaya Str., Moscow 117997 (Russian Federation); Malyshev, D. [Bogolyubov Institute for Theoretical Physics, 14-b Metrolohichna Street, Kiev 03680 (Ukraine); Pooley, G. [Astrophysics, Cavendish Laboratory, Cambridge CB3 0HE (United Kingdom)

    2012-03-10T23:59:59.000Z

    We report the discovery of a systematic constant time lag between the X-ray and radio flares of the gamma-ray binary LSI +61 303, persistent over a long, multi-year timescale. Using the data from the monitoring of the system by RXTE we show that the orbital phase of X-ray flares from the source varies from {phi}{sub X} {approx_equal} 0.35 to {phi}{sub X} {approx_equal} 0.75 on the superorbital 4.6 yr timescale. Simultaneous radio observations show that periodic radio flares always lag the X-ray flare by {Delta}{phi}{sub X-R} {approx_equal} 0.2. We propose that the constant phase lag corresponds to the time of flight of the high-energy particle-filled plasma blobs from inside the binary to the radio emission region at the distance of {approx}10 times the binary separation distance. We put forward a hypothesis that the X-ray bursts correspond to the moments of formation of plasma blobs inside the binary system.

  7. EVIDENCE OF CONTRIBUTION OF INTERVENING CLOUDS TO GAMMA-RAY BURST'S X-RAY COLUMN DENSITY

    SciTech Connect (OSTI)

    Wang, J., E-mail: wj@bao.ac.cn [National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

    2013-10-20T23:59:59.000Z

    The origin of excess of X-ray column density with respect to optical extinction in gamma-ray bursts (GRBs) is still a puzzle. A proposed explanation of the excess is the photoelectric absorption due to the intervening clouds along a GRB's line of sight. Here, we test this scenario by using the intervening Mg II absorption as a tracer of the neutral hydrogen column density of the intervening clouds. We identify a connection between the large X-ray column density (and large column density ratio of log (N{sub H,X}/N{sub H{sub I}})?0.5) and large neutral hydrogen column density probed by the Mg II doublet ratio (DR). In addition, GRBs with large X-ray column density (and large ratio of log (N{sub H,X}/N{sub H{sub I}})>0) tend to have multiple saturated intervening absorbers with DR < 1.2. These results therefore indicate an additional contribution from the intervening system to the observed X-ray column density in some GRBs, although the contribution from the host galaxy alone cannot be excluded based on this study.

  8. Development of procedures for refurbishing x-ray optics at the Advanced Light Source

    E-Print Network [OSTI]

    Yashchuk, Valeriy V.

    2013-01-01T23:59:59.000Z

    Development of procedures for refurbishing x-ray optics atpractical and robust procedures for refurbishing x-ray

  9. Pionic Photons and Neutrinos from Cosmic Ray Accelerators

    E-Print Network [OSTI]

    Francis Halzen

    2011-11-04T23:59:59.000Z

    Identifying the accelerators that produce the Galactic and extragalactic cosmic rays has been a priority mission of several generations of high energy gamma ray and neutrino telescopes; success has been elusive so far. Detecting the gamma-ray and neutrino fluxes associated with cosmic rays reaches a new watershed with the completion of IceCube, the first neutrino detector with sensitivity to the anticipated fluxes, and the construction of CTA, a ground-based gamma ray detector that will map and study candidate sources with unprecedented precision. In this paper, we revisit the prospects for revealing the sources of the cosmic rays by a multiwavelength approach; after reviewing the methods, we discuss supernova remnants, gamma ray bursts, active galaxies and GZK neutrinos in some detail.

  10. Gamma-ray burst interaction with dense interstellar medium

    E-Print Network [OSTI]

    Maxim Barkov; Gennady Bisnovatyi-Kogan

    2004-10-07T23:59:59.000Z

    Interaction of cosmological gamma ray burst radiation with the dense interstellar medium of host galaxy is considered. Gas dynamical motion of interstellar medium driven by gamma ray burst is investigated in 2D approximation for different initial density distributions of host galaxy matter and different total energy of gamma ray burst. The maximum velocity of motion of interstellar medium is $1.8\\cdot10^4$ km/s. Light curves of gamma ray burst afterglow are calculated for set of non homogeneous density, distribution gamma ray burst total energy, and different viewing angles. Spectra of gamma ray burst afterglow are modeled taking into account conversion of hard photons (soft X-ray, hard UV) to soft UV and optics photons.

  11. X-ray emission properties of galaxies in Abell 3128

    E-Print Network [OSTI]

    Russell J. Smith

    2003-07-15T23:59:59.000Z

    We use archival Chandra X-ray Observatory data to investigate X-ray emission from early-type galaxies in the rich z=0.06 cluster Abell 3128. By combining the X-ray count-rates from an input list of optically-selected galaxies, we obtain a statistical detection of X-ray flux, unbiased by X-ray selection limits. Using 87 galaxies with reliable Chandra data, X-ray emission is detected for galaxies down to M_B ~ -19.0, with only an upper limit determined for galaxies at M_B ~ -18.3. The ratio of X-ray to optical luminosities is consistent with recent determinations of the low-mass X-ray binary content of nearby elliptical galaxies. Taken individually, in contrast, we detect significant (3sigma) flux for only six galaxies. Of these, one is a foreground galaxy, while two are optically-faint galaxies with X-ray hardness ratios characteristic of active galactic nuclei. The remaining three detected galaxies are amongst the optically-brightest cluster members, and have softer X-ray spectra. Their X-ray flux is higher than that expected from X-ray binaries, by a factor 2-10; the excess suggests these galaxies have retained their hot gaseous haloes. The source with the highest L_X / L_B ratio is of unusual optical morphology with prominent sharp-edged shells. Notwithstanding these few exceptions, the cluster population overall exhibits X-ray properties consistent with their emission being dominated by X-ray binaries. We conclude that in rich cluster environments, interaction with the ambient intra-cluster medium acts to strip most galaxies of their hot halo gas.

  12. GAMMA RAYS FROM STAR FORMATION IN CLUSTERS OF GALAXIES

    SciTech Connect (OSTI)

    Storm, Emma M.; Jeltema, Tesla E.; Profumo, Stefano [Department of Physics, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States)

    2012-08-20T23:59:59.000Z

    Star formation in galaxies is observed to be associated with gamma-ray emission, presumably from non-thermal processes connected to the acceleration of cosmic-ray nuclei and electrons. The detection of gamma rays from starburst galaxies by the Fermi Large Area Telescope (LAT) has allowed the determination of a functional relationship between star formation rate and gamma-ray luminosity. Since star formation is known to scale with total infrared (8-1000 {mu}m) and radio (1.4 GHz) luminosity, the observed infrared and radio emission from a star-forming galaxy can be used to quantitatively infer the galaxy's gamma-ray luminosity. Similarly, star-forming galaxies within galaxy clusters allow us to derive lower limits on the gamma-ray emission from clusters, which have not yet been conclusively detected in gamma rays. In this study, we apply the functional relationships between gamma-ray luminosity and radio and IR luminosities of galaxies derived by the Fermi Collaboration to a sample of the best candidate galaxy clusters for detection in gamma rays in order to place lower limits on the gamma-ray emission associated with star formation in galaxy clusters. We find that several clusters have predicted gamma-ray emission from star formation that are within an order of magnitude of the upper limits derived in Ackermann et al. based on non-detection by Fermi-LAT. Given the current gamma-ray limits, star formation likely plays a significant role in the gamma-ray emission in some clusters, especially those with cool cores. We predict that both Fermi-LAT over the course of its lifetime and the future Cerenkov Telescope Array will be able to detect gamma-ray emission from star-forming galaxies in clusters.

  13. Prompt TeV Emission from Cosmic Rays Accelerated by Gamma Ray Bursts Interacting with Surrounding Stellar Wind

    E-Print Network [OSTI]

    Soebur Razzaque; Olga Mena; Charles D. Dermer

    2008-11-24T23:59:59.000Z

    Protons accelerated in the internal shocks of a long duration gamma ray burst can escape the fireball as cosmic rays by converting to neutrons. Hadronic interactions of these neutrons inside a stellar wind bubble created by the progenitor star will produce TeV gamma rays via neutral meson decay and synchrotron radiation by charged pion-decay electrons in the wind magnetic field. Such gamma rays should be observable from nearby gamma ray bursts by currently running and upcoming ground-based detectors.

  14. AugEX: AUGER ELECTRON AND X-RAY SPECTROMETER ON CHANDRAYAAN-2 ROVER

    E-Print Network [OSTI]

    Bapat, Bhas

    for determining elemental composition which have a space heritage X-Ray Fluorescence (XRF) Particle-induced X-ray fluorescence (XRF) Expected Advantage: cover low Z elements with higher sensitivity than XRF or PIXE. ACHARYA-ray absorption or charged particle bombardment X-ray emission induced by X-ray absorption: XRF X-ray emission

  15. MilagroA TeV Observatory for Gamma Ray Bursts

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Milagro­A TeV Observatory for Gamma Ray Bursts B.L. Dingus and the Milagro Collaboration Los energy gamma-rays from gamma-ray bursts. The highest energy gamma rays supply very strong constraints on the nature of gamma-ray burst sources as well as fundamental physics. Because the highest energy gamma-rays

  16. The Highest Energy Cosmic Rays, Gamma Rays and Neutrinos: Facts, Fancy and Resolution

    E-Print Network [OSTI]

    F. Halzen

    2001-11-02T23:59:59.000Z

    Although cosmic rays were discovered 90 years ago, we do not know how and where they are accelerated. There is compelling evidence that the highest energy cosmic rays are extra-galactic -- they cannot be contained by our galaxy's magnetic field anyway because their gyroradius exceeds its dimensions. Elementary elementary-particle physics dictates a universal upper limit on their energy of $5\\times10^{19}$ eV, the so-called Greisen-Kuzmin-Zatsepin cutoff; however, particles in excess of this energy have been observed, adding one more puzzle to the cosmic ray mystery. Mystery is nonetheless fertile ground for progress: we will review the facts and mention some very speculative interpretations. There is indeed a realistic hope that the oldest problem in astronomy will be resolved soon by ambitious experimentation: air shower arrays of $10^4$ km$^2$ area, arrays of air Cerenkov detectors and kilometer-scale neutrino observatories.

  17. Multi-Messenger Astronomy: Cosmic Rays, Gamma-Rays, and Neutrinos

    E-Print Network [OSTI]

    F. Halzen

    2003-02-24T23:59:59.000Z

    Although cosmic rays were discovered a century ago, we do not know where or how they are accelerated. There is a realistic hope that the oldest problem in astronomy will be solved soon by ambitious experimentation: air shower arrays of 10,000 kilometer-square area, arrays of air Cerenkov telescopes and kilometer- scale neutrino observatories. Their predecessors are producing science. We will review the highlights: - Cosmic rays: the highest energy particles and the GZK cutoff, the search for cosmic accelerators and the the Cygnus region, top-down mechanisms: photons versus protons? - TeV-energy gamma rays: blazars, how molecular clouds may have revealed proton beams, first hints of the diffuse infrared background? - Neutrinos: first results and proof of concept for technologies to construct kilometer-scale observatories.

  18. Search for cosmic-ray induced $\\gamma$-ray emission in Galaxy Clusters

    E-Print Network [OSTI]

    :,; Ajello, M; Albert, A; Allafort, A; Atwood, W B; Baldini, L; Ballet, J; Barbiellini, G; Bastieri, D; Bechtol, K; Bellazzini, R; Bloom, E D; Bonamente, E; Bottacini, E; Brandt, T J; Bregeon, J; Brigida, M; Bruel, P; Buehler, R; Buson, S; Caliandro, G A; Cameron, R A; Caraveo, P A; Cavazzuti, E; Chaves, R C G; Chiang, J; Chiaro, G; Ciprini, S; Claus, R; Cohen-Tanugi, J; Conrad, J; D'Ammando, F; de Angelis, A; de Palma, F; Dermer, C D; Digel, S W; Drell, P S; Drlica-Wagner, A; Favuzzi, C; Franckowiak, A; Funk, S; Fusco, P; Gargano, F; Gasparrini, D; Germani, S; Giglietto, N; Giordano, F; Giroletti, M; Godfrey, G; Gomez-Vargas, G A; Grenier, I A; Guiriec, S; Gustafsson, M; Hadasch, D; Hayashida, M; Hewitt, J; Hughes, R E; Jeltema, T E; Jhannesson, G; Johnson, A S; Kamae, T; Kataoka, J; Kndlseder, J; Kuss, M; Lande, J; Larsson, S; Latronico, L; Garde, M Llena; Longo, F; Loparco, F; Lovellette, M N; Lubrano, P; Mayer, M; Mazziotta, M N; McEnery, J E; Michelson, P F; Mitthumsiri, W; Mizuno, T; Monzani, M E; Morselli, A; Moskalenko, I V; Murgia, S; Nemmen, R; Nuss, E; Ohsugi, T; Orienti, M; Orlando, E; Ormes, J F; Perkins, J S; Pesce-Rollins, M; Piron, F; Pivato, G; Rain, S; Rando, R; Razzano, M; Razzaque, S; Reimer, A; Reimer, O; Ruan, J; Snchez-Conde, M; Schulz, A; Sgr, C; Siskind, E J; Spandre, G; Spinelli, P; Storm, E; Strong, A W; Suson, D J; Takahashi, H; Thayer, J G; Thayer, J B; Thompson, D J; Tibaldo, L; Tinivella, M; Torres, D F; Troja, E; Uchiyama, Y; Usher, T L; Vandenbroucke, J; Vianello, G; Vitale, V; Winer, B L; Wood, K S; Zimmer, S; Pfrommer, C; Pinzke, A

    2013-01-01T23:59:59.000Z

    Current theories predict relativistic hadronic particle populations in clusters of galaxies in addition to the already observed relativistic leptons. In these scenarios hadronic interactions give rise to neutral pions which decay into $\\gamma$ rays, that are potentially observable with the Large Area Telescope (LAT) on board the Fermi space telescope. We present a joint likelihood analysis searching for spatially extended $\\gamma$-ray emission at the locations of 50 galaxy clusters in 4 years of Fermi-LAT data under the assumption of the universal cosmic-ray model proposed by Pinzke & Pfrommer (2010). We find an excess at a significance of $2.7\\,\\sigma$, which upon closer inspection is however correlated to individual excess emission towards three galaxy clusters: Abell 400, Abell 1367 and Abell 3112. We discuss these cases in detail and conservatively attribute the emission to unmodeled background (for example, radio galaxies within the clusters). Through the combined analysis of 50 clusters we exclude h...

  19. EARLY THERMAL X-RAY EMISSION FROM LONG GAMMA-RAY BURSTS AND THEIR CIRCUMSTELLAR ENVIRONMENTS

    SciTech Connect (OSTI)

    Suzuki, Akihiro [Center for Computational Astrophysics, National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan); Shigeyama, Toshikazu [Research Center for the Early Universe, School of Science, University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2013-02-10T23:59:59.000Z

    We performed a series of hydrodynamical calculations of an ultrarelativistic jet propagating through a massive star and the circumstellar matter (CSM) to investigate the interaction between the ejecta and the CSM. We succeed in distinguishing two qualitatively different cases in which the ejecta are shocked and adiabatically cool. To examine whether the cocoon expanding at subrelativistic speeds emits any observable signal, we calculate the expected photospheric emission from the cocoon. It is found that the emission can explain early thermal X-ray emission recently found in some long gamma-ray bursts (GRBs). The result implies that the difference of the circumstellar environment of long GRBs can be probed by observing their early thermal X-ray emission.

  20. Gamma Ray Bursts: recent results and connections to very high energy Cosmic Rays and Neutrinos

    E-Print Network [OSTI]

    Pter Mszros; Katsuaki Asano; Pter Veres

    2012-09-11T23:59:59.000Z

    Gamma-ray bursts are the most concentrated explosions in the Universe. They have been detected electromagnetically at energies up to tens of GeV, and it is suspected that they could be active at least up to TeV energies. It is also speculated that they could emit cosmic rays and neutrinos at energies reaching up to the $10^{18}-10^{20}$ eV range. Here we review the recent developments in the photon phenomenology in the light of \\swift and \\fermi satellite observations, as well as recent IceCube upper limits on their neutrino luminosity. We discuss some of the theoretical models developed to explain these observations and their possible contribution to a very high energy cosmic ray and neutrino background.

  1. X-Ray Source Based on the Parametric X-Rays

    E-Print Network [OSTI]

    Alexander Lobko; Olga Lugovskaya

    2005-09-02T23:59:59.000Z

    Prospects of parametric x-rays (PXR) application for the development of a tuneable quasi-monochromatic x-ray source for medical imaging are discussed. Analysis of basic requirements for electron accelerator shows that it must be relatively low-energy and high-current linac. In comparison with known ultra-relativistic cases, at low energies PXR properties will be modified to a great extent by multiple scattering of the electrons. PXR intensity dependence on target thickness and beam energy are calculated taking multiple scattering into account. It is concluded that PXR source based on real medical accelerators is feasible and can provide x-ray flux needful for obtaining high quality medical images.

  2. Total Absorption Gamma-ray Spectrometer (TAGS) Intensity Distributions from INL's Gamma-Ray Spectrometry Center

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Greenwood, R.E.

    A 252Cf fission-product source and the INL on-line isotope separator were used to supply isotope-separated fission-product nuclides to a total absorption -ray spectrometer. This spectrometer consisted of a large (25.4-cm diameter x 30.5-cm long) NaI(Tl) detector with a 20.3-cm deep axial well in which is placed a 300-mm2 x 1.0-mm Si detector. The spectra from the NaI(Tl) detector are collected both in the singles mode and in coincidence with the B-events detected in the Si detector. Ideally, this detector would sum all the energy of the B- rays in each cascade following the population of daughter level by B- decay, so that the event could be directly associated with a particular daughter level. However, there are losses of energy from attenuation of the rays before they reach the detector, transmission of rays through the detector, escape of secondary photons from Compton scattering, escape of rays through the detector well, internal conversion, etc., and the measured spectra are thus more complicated than the ideal case and the analysis is more complex. Analysis methods have been developed to simulate all of these processes and thus provide a direct measure of the B- intensity distribution as a function of the excitation energy in the daughter nucleus. These data yield more accurate information on the B- distribution than conventional decay-scheme studies for complex decay schemes with large decay energies, because in the latter there are generally many unobserved and observed but unplaced rays. The TAGS data have been analyzed and published [R. E. Greenwood et al., Nucl Instr. and metho. A390(1997)] for 40 fission product-nuclides to determine the B- intensity distributions. [Copied from the TAGS page at http://www.inl.gov/gammaray/spectrometry/tags.shtml]. Those values are listed on this page for quick reference.

  3. High resolution x-ray and gamma ray imaging using diffraction lenses with mechanically bent crystals

    DOE Patents [OSTI]

    Smither, Robert K. (Hinsdale, IL)

    2008-12-23T23:59:59.000Z

    A method for high spatial resolution imaging of a plurality of sources of x-ray and gamma-ray radiation is provided. High quality mechanically bent diffracting crystals of 0.1 mm radial width are used for focusing the radiation and directing the radiation to an array of detectors which is used for analyzing their addition to collect data as to the location of the source of radiation. A computer is used for converting the data to an image. The invention also provides for the use of a multi-component high resolution detector array and for narrow source and detector apertures.

  4. X-ray imaging, spacecraft nuclear fission and cosmic ray contraband

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  5. X-ray generation using carbon nanotubes

    E-Print Network [OSTI]

    Parmee, Richard J.; Collins, Clare M.; Milne, William I.; Cole, Matthew T.

    2015-01-06T23:59:59.000Z

    of these sys- tems are illustrated in Figure 2(b) also outlines the principle mode of operation. Here, sealed in an inexpensive and eas- ily fabricated evacuated glass or ceramic envelope, the elec- trons are liberated from a metallic filament, often made... - ment of CNT-based FE sources is provided in [152]. Here we provide a condensed review of the progress, as it pertains to X-ray sources, since then. CNTs have some of the highest attainable aspect ratios, high thermal conductivity, low chemical...

  6. Can Naked Singularities Yield Gamma Ray Bursts?

    E-Print Network [OSTI]

    H. M. Antia

    1998-07-09T23:59:59.000Z

    Gamma-ray bursts are believed to be the most luminous objects in the Universe. There has been some suggestion that these arise from quantum processes around naked singularities. The main problem with this suggestion is that all known examples of naked singularities are massless and hence there is effectively no source of energy. It is argued that a globally naked singularity coupled with quantum processes operating within a distance of the order of Planck length of the singularity will probably yield energy burst of the order of M_pc^2\\approx2\\times 10^{16} ergs, where M_p is the Planck mass.

  7. Gamma-Ray Bursts observed by INTEGRAL

    E-Print Network [OSTI]

    S. Mereghetti

    2003-12-12T23:59:59.000Z

    During the first six months of operations, six Gamma Ray Bursts (GRBs) have been detected in the field of view of the INTEGRAL instruments and localized by the INTEGRAL Burst Alert System (IBAS): a software for the automatic search of GRBs and the rapid distribution of their coordinates. I describe the current performances of IBAS and review the main results obtained so far. The coordinates of the latest burst localized by IBAS, GRB 031203, have been distributed within 20 s from the burst onset and with an uncertainty radius of only 2.7 arcmin.

  8. Neutrino Event Rates from Gamma Ray Bursts

    E-Print Network [OSTI]

    F. Halzen; D. W. Hooper

    1999-10-08T23:59:59.000Z

    We recalculate the diffuse flux of high energy neutrinos produced by Gamma Ray Bursts (GRB) in the relativistic fireball model. Although we confirm that the average single burst produces only ~10^{-2} high energy neutrino events in a detector with 1 km^2 effective area, i.e. about 10 events per year, we show that the observed rate is dominated by burst-to-burst fluctuations which are very large. We find event rates that are expected to be larger by one order of magnitude, likely more, which are dominated by a few very bright bursts. This greatly simplifies their detection.

  9. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 LawrenceE C H NLensless X-Ray Imaging in

  10. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 LawrenceE C H NLensless X-Ray Imaging

  11. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 LawrenceE C H NLensless X-Ray ImagingLensless

  12. Lensless X-Ray Imaging in Reflection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 LawrenceE C H NLensless X-Ray

  13. SMB, Small Angle X-Ray Scattering

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared0 ResourceAwards SAGE Awards ,#2446Small Angle X-Ray Scattering

  14. SMB, X-ray Absorption Spectroscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared0 ResourceAwards SAGE Awards ,#2446Small Angle X-Ray

  15. SMB, X-ray Emission Spectroscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared0 ResourceAwards SAGE Awards ,#2446Small Angle X-RayEmission

  16. Gamma Ray Burst Neutrinos Probing Quantum Gravity

    E-Print Network [OSTI]

    M. C. Gonzalez-Garcia; F. Halzen

    2006-11-28T23:59:59.000Z

    Very high energy, short wavelength, neutrinos may interact with the space-time foam predicted by theories of quantum gravity. They would propagate like light through a crystal lattice and be delayed, with the delay depending on the energy. This will appear to the observer as a violation of Lorenz invariance. Back of the envelope calculations imply that observations of neutrinos produced by gamma ray bursts may reach Planck-scale sensitivity. We revisit the problem considering two essential complications: the imprecise timing of the neutrinos associated with their poorly understood production mechanism in the source and the indirect nature of their energy measurement made by high energy neutrino telescopes.

  17. X-ray Microscopy and Imaging: FAQs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  18. X-rays Illuminate Ancient Archimedes Text

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched FerromagnetismWaste and MaterialsWenjun1of EnergyX-rayNew MaterialsrayRelated

  19. X-Ray Nanoimaging: Instruments and Methods

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered energy consumption byAbout SRNL Home SRNL main campusMore thanX-Ray Imaging of

  20. X-Ray Science Division (XSD)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered energy consumption byAbout SRNL Home SRNL main campusMore thanX-Ray Imaging