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Sample records for ly libya hm

  1. LY

    Office of Legacy Management (LM)

    ! "..- - ; : : LY /b J:,;' "Environmental Impact Evaluation and Engineering Plan" for the Remedial Action at the Former Kellex Laboratory, Jersey City, New Jersey , Robert 3. Stem, Acting Director NEPA Affairs Division ECT is initiating the necessary activities required to accomplish the remedial action to co-t conditions of radiological contamination at the former Kellex site. The proposed action entails the excavation of some spotty areas of radiological contaminated soil. The

  2. SITES ELIHlNAlED FRCil FUW' ~1WWk'l ffi LY

    Office of Legacy Management (LM)

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  3. Constraining the Ly? escape fraction with far-infrared observations of Ly? emitters

    SciTech Connect (OSTI)

    Wardlow, Julie L.; Calanog, J.; Cooray, A.; Malhotra, S.; Zheng, Z.; Rhoads, J.; Finkelstein, S.; Bock, J.; Bridge, C.; Ciardullo, R.; Gronwall, C.; Conley, A.; Farrah, D.; Gawiser, E.; Heinis, S.; Ibar, E.; Ivison, R. J.; Marsden, G.; Oliver, S. J.; Riechers, D.; and others

    2014-05-20

    We study the far-infrared properties of 498 Ly? emitters (LAEs) at z = 2.8, 3.1, and 4.5 in the Extended Chandra Deep Field-South, using 250, 350, and 500 ?m data from the Herschel Multi-tiered Extragalactic Survey and 870 ?m data from the LABOCA ECDFS Submillimeter Survey. None of the 126, 280, or 92 LAEs at z = 2.8, 3.1, and 4.5, respectively, are individually detected in the far-infrared data. We use stacking to probe the average emission to deeper flux limits, reaching 1? depths of ?0.1 to 0.4 mJy. The LAEs are also undetected at ?3? in the stacks, although a 2.5? signal is observed at 870 ?m for the z = 2.8 sources. We consider a wide range of far-infrared spectral energy distributions (SEDs), including an M82 and an Sd galaxy template, to determine upper limits on the far-infrared luminosities and far-infrared-derived star formation rates of the LAEs. These star formation rates are then combined with those inferred from the Ly? and UV emission to determine lower limits on the LAEs' Ly? escape fraction (f {sub esc}(Ly?)). For the Sd SED template, the inferred LAEs f {sub esc}(Ly?) are ? 30% (1?) at z = 2.8, 3.1, and 4.5, which are all significantly higher than the global f {sub esc}(Ly?) at these redshifts. Thus, if the LAEs f {sub esc}(Ly?) follows the global evolution, then they have warmer far-infrared SEDs than the Sd galaxy template. The average and M82 SEDs produce lower limits on the LAE f {sub esc}(Ly?) of ?10%-20% (1?), all of which are slightly higher than the global evolution of f {sub esc}(Ly?), but consistent with it at the 2?-3? level.

  4. LyMAS: Predicting large-scale Ly? forest statistics from the dark matter density field

    SciTech Connect (OSTI)

    Peirani, Sbastien; Colombi, Stphane; Dubois, Yohan; Pichon, Christophe; Weinberg, David H.; Blaizot, Jrmy

    2014-03-20

    We describe Ly? Mass Association Scheme (LyMAS), a method of predicting clustering statistics in the Ly? forest on large scales from moderate-resolution simulations of the dark matter (DM) distribution, with calibration from high-resolution hydrodynamic simulations of smaller volumes. We use the 'Horizon-MareNostrum' simulation, a 50 h {sup 1} Mpc comoving volume evolved with the adaptive mesh hydrodynamic code RAMSES, to compute the conditional probability distribution P(F{sub s} |? {sub s}) of the transmitted flux F{sub s} , smoothed (one-dimensionally, 1D) over the spectral resolution scale, on the DM density contrast ? {sub s}, smoothed (three-dimensionally, 3D) over a similar scale. In this study we adopt the spectral resolution of the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS) at z = 2.5, and we find optimal results for a DM smoothing length ? = 0.3 h {sup 1} Mpc (comoving). In its simplest form, LyMAS draws randomly from the hydro-calibrated P(F{sub s} |? {sub s}) to convert DM skewers into Ly? forest pseudo-spectra, which are then used to compute cross-sightline flux statistics. In extended form, LyMAS exactly reproduces both the 1D power spectrum and one-point flux distribution of the hydro simulation spectra. Applied to the MareNostrum DM field, LyMAS accurately predicts the two-point conditional flux distribution and flux correlation function of the full hydro simulation for transverse sightline separations as small as 1 h {sup 1} Mpc, including redshift-space distortion effects. It is substantially more accurate than a deterministic density-flux mapping ({sup F}luctuating Gunn-Peterson Approximation{sup )}, often used for large-volume simulations of the forest. With the MareNostrum calibration, we apply LyMAS to 1024{sup 3} N-body simulations of a 300 h {sup 1} Mpc and 1.0 h {sup 1} Gpc cube to produce large, publicly available catalogs of mock BOSS spectra that probe a large comoving volume. LyMAS will be a powerful tool for interpreting 3D Ly? forest data, thereby transforming measurements from BOSS and other massive quasar absorption surveys into constraints on dark energy, DM, space geometry, and intergalactic medium physics.

  5. LINKING Ly? AND LOW-IONIZATION TRANSITIONS AT LOW OPTICAL DEPTH

    SciTech Connect (OSTI)

    Jaskot, A. E.; Oey, M. S.

    2014-08-20

    We suggest that low optical depth in the Lyman continuum (LyC) may relate the Ly? emission, C II and Si II absorption, and C II* and Si II* emission seen in high-redshift galaxies. We base this analysis on Hubble Space Telescope Cosmic Origins Spectrograph spectra of four Green Pea (GP) galaxies, which may be analogs of z > 2 Ly? emitters (LAEs). In the two GPs with the strongest Ly? emission, the Ly? line profiles show reduced signs of resonant scattering. Instead, the Ly? profiles resemble the H? line profiles of evolved star ejecta, suggesting that the Ly? emission originates from a low column density and similar outflow geometry. The weak C II absorption and presence of non-resonant C II* emission in these GPs support this interpretation and imply a low LyC optical depth along the line of sight. In two additional GPs, weak Ly? emission and strong C II absorption suggest a higher optical depth. These two GPs differ in their Ly? profile shapes and C II* emission strengths, however, indicating different inclinations of the outflows to our line of sight. With these four GPs as examples, we explain the observed trends linking Ly?, C II, and C II* in stacked LAE spectra, in the context of optical depth and geometric effects. Specifically, in some galaxies with strong Ly? emission, a low LyC optical depth may allow Ly? to escape with reduced scattering. Furthermore, C II absorption, C II* emission, and Ly? profile shape can reveal the optical depth, constrain the orientation of neutral outflows in LAEs, and identify candidate LyC emitters.

  6. ionic liquids biological-ly derived from lignin and hemicellulose

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

    biological-ly derived from lignin and hemicellulose - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste

  7. z ? 1 Ly? emitters. I. The luminosity function , , ,

    SciTech Connect (OSTI)

    Wold, Isak G. B.; Barger, Amy J.; Cowie, Lennox L. E-mail: barger@astro.wisc.edu

    2014-03-10

    We construct a flux-limited sample of 135 candidate z ? 1 Ly? emitters (LAEs) from Galaxy Evolution Explorer (GALEX) grism data using a new data cube search method. These LAEs have luminosities comparable to those at high redshifts and lie within a 7 Gyr gap present in existing LAE samples. We use archival and newly obtained optical spectra to verify the UV redshifts of these LAEs. We use the combination of the GALEX UV spectra, optical spectra, and X-ray imaging data to estimate the active galactic nucleus (AGN) fraction and its dependence on Ly? luminosity. We remove the AGNs and compute the luminosity function (LF) from 60 z ? 1 LAE galaxies. We find that the best-fit LF implies a luminosity density increase by a factor of ?1.5 from z ? 0.3 to z ? 1 and ?20 from z ? 1 to z ? 2. We find a z ? 1 volumetric Ly? escape fraction of 0.7% 0.4%.

  8. AIR SHIPMENT OF HIGHLY ENRICHED URANIUM SPENT NUCLEAR FUEL FROM ROMANIA AND LIBYA

    SciTech Connect (OSTI)

    Christopher Landers; Igor Bolshinsky; Ken Allen; Stanley Moses

    2010-07-01

    In June 2009 Romania successfully completed the worlds first air shipment of highly enriched uranium (HEU) spent nuclear fuel transported in Type B(U) casks under existing international laws and without special exceptions for the air transport licenses. Special 20-foot ISO shipping containers and cask tiedown supports were designed to transport Russian TUK 19 shipping casks for the Romanian air shipment and the equipment was certified for all modes of transport, including road, rail, water, and air. In December 2009 Libya successfully used this same equipment for a second air shipment of HEU spent nuclear fuel. Both spent fuel shipments were transported by truck from the originating nuclear facilities to nearby commercial airports, were flown by commercial cargo aircraft to a commercial airport in Yekaterinburg, Russia, and then transported by truck to their final destinations at the Production Association Mayak facility in Chelyabinsk, Russia. Both air shipments were performed under the Russian Research Reactor Fuel Return Program (RRRFR) as part of the U.S. National Nuclear Security Administration (NNSA) Global Threat Reduction Initiative (GTRI). The Romania air shipment of 23.7 kg of HEU spent fuel from the VVR S research reactor was the last of three HEU fresh and spent fuel shipments under RRRFR that resulted in Romania becoming the 3rd RRRFR participating country to remove all HEU. Libya had previously completed two RRRFR shipments of HEU fresh fuel so the 5.2 kg of HEU spent fuel air shipped from the IRT 1 research reactor in December made Libya the 4th RRRFR participating country to remove all HEU. This paper describes the equipment, preparations, and license approvals required to safely and securely complete these two air shipments of spent nuclear fuel.

  9. Accelerated evolution of the Ly? luminosity function at z ? 7 revealed by the Subaru ultra-deep survey for Ly? emitters at z = 7.3

    SciTech Connect (OSTI)

    Konno, Akira; Ouchi, Masami; Ono, Yoshiaki; Shibuya, Takatoshi; Naito, Yoshiaki; Momose, Rieko; Yuma, Suraphong; Shimasaku, Kazuhiro; Nakajima, Kimihiko; Furusawa, Hisanori; Iye, Masanori

    2014-12-10

    We present the ultra-deep Subaru narrowband imaging survey for Ly? emitters (LAEs) at z = 7.3 in the Subaru/XMM-Newton Deep Survey (SXDS) and Cosmic Evolution Survey (COSMOS) fields (?0.5 deg{sup 2}) with a total integration time of 106 hr. Exploiting our new sharp bandwidth filter, NB101, installed on the Suprime-Cam, we have reached L(Ly?) = 2.4 10{sup 42} erg s{sup 1} (5?) for z = 7.3 LAEs, about four times deeper than previous Subaru z ? 7 studies, which allows us to reliably investigate the evolution of the Ly? luminosity function (LF) for the first time down to the luminosity limit same as those of Subaru z = 3.1-6.6 LAE samples. Surprisingly, we only find three and four LAEs in the SXDS and COSMOS fields, respectively, while one expects a total of ?65 LAEs by our survey in the case of no Ly? LF evolution from z = 6.6 to 7.3. We identify a decrease of the Ly? LF from z = 6.6 to 7.3 at the >90% confidence level from our z = 7.3 Ly? LF with the best-fit Schechter parameters of L{sub Ly?}{sup ?}=2.7{sub ?1.2}{sup +8.0}10{sup 42} erg s{sup ?1} and ?{sup ?}=3.7{sub ?3.3}{sup +17.6}10{sup ?4} Mpc{sup ?3} for a fixed ? = 1.5. Moreover, the evolution of the Ly? LF is clearly accelerated at z > 6.6 beyond the measurement uncertainties including cosmic variance. Because no such accelerated evolution of the UV-continuum LF or the cosmic star formation rate (SFR) is found at z ? 7, but suggested only at z > 8, this accelerated Ly? LF evolution is explained by physical mechanisms different from a pure SFR decrease but related to the Ly? production and escape in the process of cosmic reionization. Because a simple accelerating increase of intergalactic medium neutral hydrogen absorbing Ly? cannot be reconciled with Thomson scattering of optical depth measurements from WMAP and Planck, our findings may support new physical pictures suggested by recent theoretical studies, such as the existence of HI clumpy clouds within cosmic ionized bubbles that are selectively absorbing Ly? and the large ionizing photon escape fraction of galaxies causing weak Ly? emission.

  10. COMPUTING INTRINSIC LY{alpha} FLUXES OF F5 V TO M5 V STARS

    SciTech Connect (OSTI)

    Linsky, Jeffrey L.; France, Kevin; Ayres, Tom

    2013-04-01

    The Ly{alpha} emission line dominates the far-ultraviolet spectra of late-type stars and is a major source for photodissociation of important molecules including H{sub 2}O, CH{sub 4}, and CO{sub 2} in exoplanet atmospheres. The incident flux in this line illuminating an exoplanet's atmosphere cannot be measured directly as neutral hydrogen in the interstellar medium (ISM) attenuates most of the flux reaching the Earth. Reconstruction of the intrinsic Ly{alpha} line has been accomplished for a limited number of nearby stars, but is not feasible for distant or faint host stars. We identify correlations connecting the intrinsic Ly{alpha} flux with the flux in other emission lines formed in the stellar chromosphere, and find that these correlations depend only gradually on the flux in the other lines. These correlations, which are based on Hubble Space Telescope spectra, reconstructed Ly{alpha} line fluxes, and irradiance spectra of the quiet and active Sun, are required for photochemical models of exoplanet atmospheres when intrinsic Ly{alpha} fluxes are not available. We find a tight correlation of the intrinsic Ly{alpha} flux with stellar X-ray flux for F5 V to K5 V stars, but much larger dispersion for M stars. We also show that knowledge of the stellar effective temperature and rotation rate can provide reasonably accurate estimates of the Ly{alpha} flux for G and K stars, and less accurate estimates for cooler stars.

  11. A z ? 5.7 Ly? emission line with an ultrabroad red wing

    SciTech Connect (OSTI)

    Yang, Huan; Wang, JunXian; Zheng, Zhen-Ya; Malhotra, Sangeeta; Rhoads, James E.; Infante, Leopoldo E-mail: jxw@mail.ustc.edu.cn E-mail: smalhotr@asu.edu E-mail: linfante@astro.puc.cl

    2014-03-20

    Using the Ly? emission line as a tracer of high-redshift, star-forming galaxies, hundreds of Ly? emission line galaxies (LAEs) at z > 5 have been detected. These LAEs are considered to be low-mass young galaxies, critical to the re-ionization of the universe and the metal enrichment of the circumgalactic medium (CGM) and the intergalactic medium (IGM). It is assumed that outflows in LAEs can help both ionizing photons and Ly? photons escape from galaxies. However, we still know little about the outflows in high-redshift LAEs due to observational difficulties, especially at redshift >5. Models of Ly? radiative transfer predict asymmetric Ly? line profiles with broad red wings in LAEs with outflows. Here, we report a z ? 5.7 Ly? emission line with a broad red wing extending to >1000 km s{sup 1} relative to the peak of Ly? line, which has been detected in only a couple of z > 5 LAEs until now. If the broad red wing is ascribed to gas outflow instead of active galactic nucleus activity, the outflow velocity could be larger than the escape velocity (?500 km s{sup 1}) of a typical halo mass of z ? 5.7 LAEs, which is consistent with the idea that outflows in LAEs disperse metals to CGM and IGM.

  12. Ly{alpha} EMITTERS AT z = 7 IN THE SUBARU/XMM-NEWTON DEEP SURVEY FIELD:

    Office of Scientific and Technical Information (OSTI)

    PHOTOMETRIC CANDIDATES AND LUMINOSITY FUNCTION (Journal Article) | SciTech Connect Ly{alpha} EMITTERS AT z = 7 IN THE SUBARU/XMM-NEWTON DEEP SURVEY FIELD: PHOTOMETRIC CANDIDATES AND LUMINOSITY FUNCTION Citation Details In-Document Search Title: Ly{alpha} EMITTERS AT z = 7 IN THE SUBARU/XMM-NEWTON DEEP SURVEY FIELD: PHOTOMETRIC CANDIDATES AND LUMINOSITY FUNCTION We conducted a deep narrowband NB973 (FWHM = 200 A centered at 9755 A) survey of z = 7 Ly{alpha} emitters (LAEs) in the

  13. The impact of gas bulk rotation on the Ly? line

    SciTech Connect (OSTI)

    Garavito-Camargo, Juan N.; Forero-Romero, Jaime E.; Dijkstra, Mark E-mail: je.forero@uniandes.edu.co

    2014-11-10

    We present results of radiative transfer calculations to measure the impact of gas bulk rotation on the morphology of the Ly? emission line in distant galaxies. We model a galaxy as a sphere with an homogeneous mixture of dust and hydrogen at a constant temperature. These spheres undergo solid-body rotation with maximum velocities in the range 0-300 km s{sup 1} and neutral hydrogen optical depths in the range ?{sub H} = 10{sup 5}-10{sup 7}. We consider two types of source distributions in the sphere: central and homogeneous. Our main result is that rotation introduces a dependence of the line morphology with viewing angle and rotational velocity. Observations with a line of sight parallel to the rotation axis yield line morphologies similar to the static case. For lines of sight perpendicular to the rotation axis, both the intensity at the line center and the line width increase with rotational velocity. Along the same line of sight, the line becomes single peaked at rotational velocities close to half the line width in the static case. Notably, we find that rotation does not induce any spatial anisotropy in the integrated line flux, the escape fraction or the average number of scatterings. This is because Lyman scattering through a rotating solid-body proceeds identically to the static case. The only difference is the Doppler shift from the different regions in the sphere that move with respect to the observer. This allows us to derive an analytic approximation for the viewing-angle dependence of the emerging spectrum, as a function of rotational velocity.

  14. X-RAY CONSTRAINTS ON THE Ly{alpha} ESCAPE FRACTION

    SciTech Connect (OSTI)

    Zheng Zhenya; Wang Junxian; Malhotra, Sangeeta; Rhoads, James E.; Finkelstein, Steven L.; Gawiser, Eric; Gronwall, Caryl; Ciardullo, Robin; Guaita, Lucia; Nilsson, Kim K.

    2012-02-10

    We have co-added the X-ray flux of all known Ly{alpha} emitters (LAEs) in the 4 Ms Chandra Deep Field South (CDF-S) region, achieving the tightest upper limits yet on the X-ray to Ly{alpha} ratio. We use the X-ray data to place sensitive upper limits on the average unobscured star formation rate (SFR{sub X}) in these galaxies. A very small fraction of Ly{alpha} galaxies in the field are individually detected in the X-rays, implying a low fraction of active galactic nucleus activity. After excluding the few X-ray-detected LAEs, we stack the undetected LAEs located in the 4 Ms CDF-S data and 250 ks Extended CDF-S (ECDF-S) data, and compute a 1{sigma} upper limit on SFR{sub X} < 1.6, 14, 28, 28, 140, 440, 880 M{sub Sun} yr{sup -1} for LAEs located at z {approx} 0.3 and z = 2.1, 3.1, 3.2, 4.5, 5.7, and 6.5, respectively. The upper limit of SFR{sub X} in LAEs can be then compared to SFR{sub Ly{alpha}} derived from Ly{alpha} line and thus can constrain on the Ly{alpha} escape fraction (f{sup Esc}{sub Ly{alpha}}). The f{sup Esc}{sub Ly{alpha}} from X-ray at z {approx} 0.3 is substantially larger than that from UV or H{alpha}. Three X-ray-detected LAE galaxies at z {approx} 0.3 show f{sup Esc}{sub Ly{alpha}} {approx} 3%-22%, and the average Ly{alpha} escape fraction from stacking the X-ray-undetected LAEs show f{sup Esc}{sub Ly{alpha}} > 28% at 3{sigma} significance level at the same redshift. We derive a lower limit on f{sup Esc}{sub Ly{alpha}} > 14% (84% confidence level, 1{sigma} lower limit) for LAEs at redshift z {approx} 2.1 and z {approx} 3.1-3.2. At z > 4, the current LAE samples are not of sufficient size to constrain SFR{sub X} well. By averaging all the LAEs at z > 2, the X-ray non-detection constrains f{sup Esc}{sub Ly{alpha}} > 17% (84% confidence level, 1{sigma} lower limit), and rejects f{sup Esc}{sub Ly{alpha}} < 5.7% at the 99.87% confidence level from 2.1 < z < 6.5.

  15. HM-ACCESS Project (Framework for the Use of Electronic Shipping Papers for the Transport of Hazardous Materials)

    Office of Environmental Management (EM)

    and Hazardous Materials Safety Administration HM-ACCESS Initiative James Simmons Acting Chief, Research and Development Office of Hazardous Materials Safety Engineering and Research Division May 2012 U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 2 H-azardous M-aterials A-utomated C-argo C-ommunication for E-fficient and S-afe S-hipments U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration Background Purpose: To

  16. A submillimeter galaxy illuminating its circumgalactic medium: Ly? scattering in a cold, clumpy outflow

    SciTech Connect (OSTI)

    Geach, J. E.; Coppin, K. E. K.; Smith, D. J. B.; Bower, R. G.; Alexander, D. M.; Swinbank, A. M.; Blain, A. W.; Bremer, M. N.; Chapin, E. L.; Chapman, S. C.; Clements, D. L.; Dunlop, J. S.; Koprowski, M. P.; Micha?owski, M. J.; Farrah, D.; Jenness, T.; Robson, E. I.; Scott, D.; Spaans, M.; Van der Werf, P.

    2014-09-20

    We report the detection at 850 ?m of the central source in SSA22-LAB1, the archetypal 'Lyman-? Blob' (LAB), a 100 kpc scale radio-quiet emission-line nebula at z = 3.1. The flux density of the source, S {sub 850} = 4.6 1.1 mJy, implies the presence of a galaxy or group of galaxies with a total luminosity of L {sub IR} ? 10{sup 12} L {sub ?}. The position of an active source at the center of a ?50 kpc radius ring of linearly polarized Ly? emission detected by Hayes et al. suggests that the central source is leaking Ly? photons preferentially in the plane of the sky, which undergo scattering in H I clouds at a large galactocentric radius. The Ly? morphology around the submillimeter detection is reminiscent of a biconical outflow, and the average Ly? line profiles of the two 'lobes' are dominated by a red peak, which is expected for a resonant line emerging from a medium with a bulk velocity gradient that is outflowing relative to the line center. Taken together, these observations provide compelling evidence that the central active galaxy (or galaxies) is responsible for a large fraction of the extended Ly? emission and morphology. Less clear is the history of the cold gas in the circumgalactic medium being traced by Ly?: is it mainly pristine material accreting into the halo that has not yet been processed through an interstellar medium (ISM), now being blown back as it encounters an outflow, or does it mainly comprise gas that has been swept-up within the ISM and expelled from the galaxy?.

  17. Foreground contamination in Ly? intensity mapping during the epoch of reionization

    SciTech Connect (OSTI)

    Gong, Yan; Cooray, Asantha; Silva, Marta; Santos, Mario G.

    2014-04-10

    The intensity mapping of Ly? emission during the epoch of reionization will be contaminated by foreground emission lines from lower redshifts. We calculate the mean intensity and the power spectrum of Ly? emission at z ? 7 and estimate the uncertainties according to the relevant astrophysical processes. We find that the low-redshift emission lines from 6563 H?, 5007 [O III], and 3727 [O II] will be strong contaminants on the observed Ly? power spectrum. We make use of both the star formation rate and luminosity functions to estimate the mean intensity and power spectra of the three foreground lines at z ? 0.5 for H?, z ? 0.9 for [O III], and z ? 1.6 for [O II], as they will contaminate the Ly? emission at z ? 7. The [O II] line is found to be the strongest. We analyze the masking of the bright survey pixels with a foreground line above some line intensity threshold as a way to reduce the contamination in an intensity mapping survey. We find that the foreground contamination can be neglected if we remove pixels with fluxes above 1.4 10{sup 20} W m{sup 2}.

  18. He II Ly{beta} GUNN-PETERSON ABSORPTION: NEW HST OBSERVATIONS AND THEORETICAL EXPECTATIONS

    SciTech Connect (OSTI)

    Syphers, David; Pieri, Matthew; Shull, J. Michael; Anderson, Scott F.; Zheng, Wei; Kriss, Gerard A.; Smith, Britton; Meiksin, Avery; Schneider, Donald P.; York, Donald G.

    2011-12-01

    Observations of He II Ly{alpha} Gunn-Peterson troughs have proved to be a valuable probe of the epoch of helium reionization at z {approx} 3. Since this optical depth can become unmeasurably large even for modest He II fractions, various alternate techniques have been proposed to push to higher redshift, and among the more promising is looking at higher-order Lyman-series troughs. We here report four new observations of the He II Ly{beta} trough, including new data on the only sightline with a prior Ly{beta} observation. However, the effective optical depth ratio {tau}{sub eff,{beta}}/{tau}{sub eff,{alpha}} is not simply predicted by f{sub {beta}}{lambda}{sub {beta}}/f{sub {alpha}}{lambda}{sub {alpha}} = 0.16, and we analyze cosmological simulations to find that the correct ratio for helium at z {approx} 3 is {approx_equal}0.35. In one case we infer {tau}{sub eff,{alpha}} > 8.8, strong evidence that helium was not fully reionized at z = 3.2-3.5, in agreement with previous measurements suggesting a later completion of reionization.

  19. Ly{alpha} ESCAPE FROM z {approx} 0.03 STAR-FORMING GALAXIES: THE DOMINANT ROLE OF OUTFLOWS

    SciTech Connect (OSTI)

    Wofford, Aida; Leitherer, Claus [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Salzer, John, E-mail: wofford@stsci.edu [Astronomy Department, Indiana University, Swain West 408, 727 East Third Street, Bloomington, IN 47405 (United States)

    2013-03-10

    The usefulness of H I Ly{alpha} photons for characterizing star formation in the distant universe is limited by our understanding of the astrophysical processes that regulate their escape from galaxies. These processes can only be observed in detail out to a few Multiplication-Sign 100 Mpc. Past nearby (z < 0.3) spectroscopic studies are based on small samples and/or kinematically unresolved data. Taking advantage of the high sensitivity of Hubble Space Telescope's Cosmic Origins Spectrograph (COS), we observed the Ly{alpha} lines of 20 H{alpha}-selected galaxies located at =0.03. The galaxies cover a broad range of luminosity, oxygen abundance, and reddening. In this paper, we characterize the observed Ly{alpha} lines and establish correlations with fundamental galaxy properties. We find seven emitters. These host young ({<=}10 Myr) stellar populations have rest-frame equivalent widths in the range 1-12 A, and have Ly{alpha} escape fractions within the COS aperture in the range 1%-12%. One emitter has a double-peaked Ly{alpha} with peaks 370 km s{sup -1} apart and a stronger blue peak. Excluding this object, the emitters have Ly{alpha} and O I {lambda}1302 offsets from H{alpha} in agreement with expanding-shell models and Lyman break galaxies observations. The absorbers have offsets that are almost consistent with a static medium. We find no one-to-one correspondence between Ly{alpha} emission and age, metallicity, or reddening. Thus, we confirm that Ly{alpha} is enhanced by outflows and is regulated by the dust and H I column density surrounding the hot stars.

  20. PREDICTING Lyα AND Mg II FLUXES FROM K AND M DWARFS USING GALAXY EVOLUTION EXPLORER ULTRAVIOLET PHOTOMETRY

    SciTech Connect (OSTI)

    Shkolnik, Evgenya L.; Rolph, Kristina A.; Peacock, Sarah; Barman, Travis S. E-mail: kristina.rolph@fandm.edu E-mail: barman@lpl.arizona.edu

    2014-11-20

    A star's ultraviolet (UV) emission can greatly affect the atmospheric chemistry and physical properties of closely orbiting planets with the potential for severe mass loss. In particular, the Lyα emission line at 1216 Å, which dominates the far-ultraviolet (FUV) spectrum, is a major source of photodissociation of important atmospheric molecules such as water and methane. The intrinsic flux of Lyα, however, cannot be directly measured due to the absorption of neutral hydrogen in the interstellar medium and contamination by geocoronal emission. To date, reconstruction of the intrinsic Lyα line based on Hubble Space Telescope spectra has been accomplished for 46 FGKM nearby stars, 28 of which have also been observed by the Galaxy Evolution Explorer (GALEX). Our investigation provides a correlation between published intrinsic Lyα and GALEX far- and near-ultraviolet (NUV) chromospheric fluxes for K and M stars. The negative correlations between the ratio of the Lyα to the GALEX fluxes reveal how the relative strength of Lyα compared to the broadband fluxes weakens as the FUV and NUV excess flux increase. We also correlate GALEX fluxes with the strong NUV Mg II h+k spectral emission lines formed at lower chromospheric temperatures than Lyα. The reported correlations provide estimates of intrinsic Lyα and Mg II fluxes for the thousands of K and M stars in the archived GALEX all-sky surveys. These will constrain new stellar upper atmosphere models for cool stars and provide realistic inputs to models describing exoplanetary photochemistry and atmospheric evolution in the absence of UV spectroscopy.

  1. BROAD Ly{alpha} EMISSION FROM THREE NEARBY BL LACERTAE OBJECTS

    SciTech Connect (OSTI)

    Stocke, John T.; Danforth, Charles W. [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, 389-UCB, Boulder, CO 80309 (United States); Perlman, Eric S., E-mail: danforth@casa.colorado.edu, E-mail: stocke@casa.colorado.edu, E-mail: eperlman@fit.edu [Florida Institute of Technology, Physics and Space Sciences Department, 150 West University Boulevard, Melbourne, FL 32901 (United States)

    2011-05-10

    We present far-UV HST/COS spectra of four nearby BL Lac objects. BL Lac spectra are dominated by a smooth, power-law continuum which arises in a relativistic jet. However, the spectra are not necessarily featureless; weak, broad- and/or narrow-line emission is sometimes seen in high-quality optical spectra. We present detections of Ly{alpha} emission in HST/COS spectra of Mrk 421 (z = 0.030) and PKS 2005-489 (z = 0.071) as well as an archival HST/GHRS observation of Mrk 501 (z = 0.0337). Archival HST/STIS observations of PKS 2155-304 (z = 0.116) show no Ly{alpha} emission to a very low upper limit. Using the assumption that the broad-line region (BLR) clouds are symmetrically placed around the active galactic nucleus (AGN), we use these measured Ly{alpha} emission features to constrain either the relativistic {Gamma} values for the ionizing continuum produced by the jet (in the ionization-bounded case) or the mass of warm gas (in the density-bounded case). While realistic {Gamma} values can be obtained for all four cases, the values for Mrk 421 and PKS 2155-304 are high enough to suggest that covering factors of BLR clouds of {approx}1%-2% might be required to provide consistency with earlier values of Doppler boosting and viewing angles suggested for this class of BL Lacs. This discrepancy also exists in the case of M 87, where the amount of Doppler boosting in our direction is expected to be minimal, again suggestive of a small covering factor of BLR clouds. If, as these small covering factors might suggest, the assumptions of a density-bounded model could be more correct, then the observed Ly{alpha} luminosities require that BL Lac/FR 1 nuclei possess very little warm gas (10{sup -4} to 10{sup -5} M{sub sun}) as suggested by Guilbert et al. If these clouds are in pressure balance with a hotter ({approx}10{sup 6} K) gas, the BLR contains too little mass to power the AGN by accretion alone.

  2. 2011 HM{sub 102}: DISCOVERY OF A HIGH-INCLINATION L5 NEPTUNE TROJAN IN THE SEARCH FOR A POST-PLUTO NEW HORIZONS TARGET

    SciTech Connect (OSTI)

    Parker, Alex H.; Holman, Matthew J.; McLeod, Brian A.; Buie, Marc W.; Borncamp, David M.; Spencer, John R.; Stern, S. Alan; Osip, David J.; Gwyn, Stephen D. J.; Fabbro, Sebastian; Kavelaars, J. J.; Benecchi, Susan D.; Sheppard, Scott S.; Binzel, Richard P.; DeMeo, Francesca E.; Fuentes, Cesar I.; Trilling, David E.; Gay, Pamela L.; Petit, Jean-Marc; Tholen, David J.; and others

    2013-04-15

    We present the discovery of a long-term stable L5 (trailing) Neptune Trojan in data acquired to search for candidate trans-Neptunian objects for the New Horizons spacecraft to fly by during an extended post-Pluto mission. This Neptune Trojan, 2011 HM{sub 102}, has the highest inclination (29. Degree-Sign 4) of any known member of this population. It is intrinsically brighter than any single L5 Jupiter Trojan at H{sub V} {approx} 8.18. We have determined its gri colors (a first for any L5 Neptune Trojan), which we find to be similar to the moderately red colors of the L4 Neptune Trojans, suggesting similar surface properties for members of both Trojan clouds. We also present colors derived from archival data for two L4 Neptune Trojans (2006 RJ{sub 103} and 2007 VL{sub 305}), better refining the overall color distribution of the population. In this document we describe the discovery circumstances, our physical characterization of 2011 HM{sub 102}, and this object's implications for the Neptune Trojan population overall. Finally, we discuss the prospects for detecting 2011 HM{sub 102} from the New Horizons spacecraft during its close approach in mid- to late-2013.

  3. HUBBLE/COS OBSERVATIONS OF THE Ly{alpha} FOREST TOWARD THE BL Lac OBJECT 1ES 1553+113

    SciTech Connect (OSTI)

    Danforth, Charles W.; Keeney, Brian A.; Stocke, John T.; Shull, J. Michael; Yao Yangsen, E-mail: danforth@casa.colorado.ed [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, 389-UCB, Boulder, CO 80309 (United States)

    2010-09-01

    We present new moderate-resolution, far-ultraviolet spectra from the Hubble Space Telescope/Cosmic Origins Spectrograph (HST/COS) of the BL Lac object 1ES 1553+113 covering the wavelength range 1135 A < {lambda} < 1795 A. The data show a smooth continuum with a wealth of narrow (b < 100 km s{sup -1}) absorption features arising in the interstellar medium and intergalactic medium. These features include 41 Ly{alpha} absorbers at 0 < z{sub abs} < 0.43, 14 of which are detected in multiple Lyman lines and 6 of which show absorption in one or more metal lines. We analyze a metal-rich triplet ({Delta}cz {approx} 1000 km s{sup -1}) of Ly{alpha} absorbers at z{sub abs} {approx} 0.188 in which O VI, N V, and C III absorption is detected. Silicon ions (Si III, Si IV) are not detected to fairly strong upper limits and we use the measured Si III/C III upper limit to derive an abundance limit (C/Si) {>=} 4(C/Si){sub sun} for the strongest component of the absorber complex. Galaxy redshift surveys show a number of massive galaxies at approximately the same redshift as this absorption complex, suggesting that it arises in a large-scale galaxy filament. As one of the brightest extragalactic X-ray and {gamma}-ray sources, 1ES 1553+113 is of great interest to the high-energy astrophysics community. With no intrinsic emission or absorption features, 1ES 1553+113 has no direct redshift determination. We use intervening Ly{alpha} absorbers to place a direct limit on the redshift: z{sub em}>0.395 based on a confirmed Ly{alpha}+O VI absorber and z{sub em}>0.433 based on a single-line detection of Ly{alpha}. The current COS data are only sensitive to Ly{alpha} absorbers at z < 0.47, but we present statistical arguments that z{sub em} {approx}< 0.58 (at a 1{sigma} confidence limit) based on the non-detection of any Ly{beta} absorbers at z>0.4.

  4. LY? FOREST TOMOGRAPHY FROM BACKGROUND GALAXIES: THE FIRST MEGAPARSEC-RESOLUTION LARGE-SCALE STRUCTURE MAP AT z > 2

    SciTech Connect (OSTI)

    Lee, Khee-Gan; Hennawi, Joseph F.; Eilers, Anna-Christina [Max Planck Institute for Astronomy, Knigstuhl 17, D-69117 Heidelberg (Germany); Stark, Casey; White, Martin [Department of Astronomy, University of California at Berkeley, B-20 Hearst Field Annex 3411, Berkeley, CA 94720 (United States); Prochaska, J. Xavier [Department of Astronomy and Astrophysics, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States); Schlegel, David J. [University of California Observatories, Lick Observatory, 1156 High Street, Santa Cruz, CA 95064 (United States); Arinyo-i-Prats, Andreu [Institut de Cincies del Cosmos, Universitat de Barcelona (IEEC-UB), Mart Franqus 1, E-08028 Barcelona (Spain); Suzuki, Nao [Kavli Institute for the Physics and Mathematics of the Universe (IPMU), The University of Tokyo, Kashiwano-ha 5-1-5, Kashiwa-shi, Chiba (Japan); Croft, Rupert A. C. [Department of Physics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213 (United States); Caputi, Karina I. [Kapteyn Astronomical Institute, University of Groningen, P.O. Box 800, 9700-AV Groningen (Netherlands); Cassata, Paolo [Instituto de Fisica y Astronomia, Facultad de Ciencias, Universidad de Valparaiso, Av. Gran Bretana 1111, Casilla 5030, Valparaiso (Chile); Ilbert, Olivier; Le Brun, Vincent; Le Fvre, Olivier [Aix Marseille Universit, CNRS, LAM (Laboratoire d'Astrophysique de Marseille) UMR 7326, F-13388 Marseille (France); Garilli, Bianca [INAF-IASF, Via Bassini 15, I-20133, Milano (Italy); Koekemoer, Anton M. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Maccagni, Dario [INAF-Osservatorio Astronomico di Bologna, Via Ranzani,1, I-40127 Bologna (Italy); Nugent, Peter, E-mail: lee@mpia.de [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); and others

    2014-11-01

    We present the first observations of foreground Ly? forest absorption from high-redshift galaxies, targeting 24 star-forming galaxies (SFGs) with z ? 2.3-2.8 within a 5' 14' region of the COSMOS field. The transverse sightline separation is ?2 h {sup 1} Mpc comoving, allowing us to create a tomographic reconstruction of the three-dimensional (3D) Ly? forest absorption field over the redshift range 2.20 ? z ? 2.45. The resulting map covers 6 h {sup 1} Mpc 14 h {sup 1} Mpc in the transverse plane and 230 h {sup 1} Mpc along the line of sight with a spatial resolution of ?3.5 h {sup 1} Mpc, and is the first high-fidelity map of a large-scale structure on ?Mpc scales at z > 2. Our map reveals significant structures with ? 10 h {sup 1} Mpc extent, including several spanning the entire transverse breadth, providing qualitative evidence for the filamentary structures predicted to exist in the high-redshift cosmic web. Simulated reconstructions with the same sightline sampling, spectral resolution, and signal-to-noise ratio recover the salient structures present in the underlying 3D absorption fields. Using data from other surveys, we identified 18 galaxies with known redshifts coeval with our map volume, enabling a direct comparison with our tomographic map. This shows that galaxies preferentially occupy high-density regions, in qualitative agreement with the same comparison applied to simulations. Our results establish the feasibility of the CLAMATO survey, which aims to obtain Ly? forest spectra for ?1000 SFGs over ?1 deg{sup 2} of the COSMOS field, in order to map out the intergalactic medium large-scale structure at (z) ? 2.3 over a large volume (100 h {sup 1} Mpc){sup 3}.

  5. L)HM+H)/&D)$&'()$#&*+,%-./%&

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

    "OFJJ"KI""L >??ZEZ???&L%& I.H+-&LI;Q'& &J.,+GG%++2%&C%,"-,&. ... I@"X@YK,+Z(B9".@"..L I.H+-&LI;Q'& &J.,+GG%++2%&C%,"-,&.& ...

  6. HST/COS detection of deuterated molecular hydrogen in a damped Ly? system at z = 0.18

    SciTech Connect (OSTI)

    Oliveira, Cristina M.; Sembach, Kenneth R.; Tumlinson, Jason; Thom, Christopher [Space Telescope Science Institute, Baltimore, MD 21218 (United States); O'Meara, John, E-mail: oliveira@stsci.edu [Saint Michael's College, Colchester, VT 05439 (United States)

    2014-03-01

    We report on the detection of deuterated molecular hydrogen, HD, at z = 0.18. HD and H{sub 2} are detected in HST/COS data of a low-metallicity (Z ? 0.07 Z {sub ?}) damped Ly? (DLA) system at z = 0.18562 toward QSO B012028, with log N(H I) = 20.50 0.10. Four absorption components are clearly resolved in H{sub 2}, while two components are resolved in HD; the bulk of the molecular hydrogen is associated with the components traced by HD. We find total column densities log N(HD) = 14.82 0.15 and log N(H{sub 2}) = 20.00 0.10. This system has a high molecular fraction, f(H{sub 2}) = 0.39 0.10, and a low HD-to-H{sub 2} ratio, log (HD/2H{sub 2}) = 5.5 0.2 dex. The excitation temperature, T {sub 01} = 65 2 K, in the component containing the bulk of the molecular gas is lower than in other DLAs. These properties are unlike those in other higher redshift DLA systems known to contain HD, but are consistent with what is observed in dense clouds in the Milky Way.

  7. X-RAY PROPERTIES OF THE z {approx} 4.5 Ly{alpha} EMITTERS IN THE CHANDRA DEEP FIELD SOUTH REGION

    SciTech Connect (OSTI)

    Zheng, Z. Y.; Wang, J. X.; Finkelstein, S. L.; Finkelstein, K. D.; Malhotra, S.; Rhoads, J. E. E-mail: jxw@ustc.edu.c

    2010-07-20

    We report the first X-ray detection of Ly{alpha} emitters (LAEs) at redshift z {approx} 4.5. One source (J033127.2-274247) is detected in the Extended Chandra Deep Field-South (ECDF-S) X-ray data and has been spectroscopically confirmed as a z = 4.48 quasar with L{sub X} = 4.2 x 10{sup 44} erg s{sup -1}. The single detection gives an Ly{alpha} quasar density of {approx} 2.7{sup +6.2} {sub -2.2} x 10{sup -6} Mpc{sup -3}, consistent with the X-ray luminosity function of quasars. Another 22 LAEs in the central Chandra Deep Field-South region are not detected individually, but their co-added counts yield an S/N = 2.4 (p = 99.83%) detection at soft band, with an effective exposure time of {approx}36 Ms. Further analysis of the equivalent width (EW) distribution shows that all the signals come from 12 LAE candidates with EW{sub rest}< 400 A and 2 of them contribute about half of the signal. From follow-up spectroscopic observations, we find that one of the two is a low-redshift emission-line galaxy, and the other is a Lyman break galaxy at z = 4.4 with little or no Ly{alpha} emission. Excluding these two and combined with ECDF-S data, we derive a 3{sigma} upper limit on the average X-ray flux of F {sub 0.5-2.0keV} < 1.6 x 10{sup -18} erg cm{sup -2} s{sup -1}, which corresponds to an average luminosity of (L {sub 0.5-2keV}) <2.4 x 10{sup 42} erg s{sup -1} for z {approx} 4.5 LAEs. If the average X-ray emission is due to star formation, it corresponds to a star formation rate (SFR) of <180-530 M {sub sun} yr{sup -1}. We use this SFR {sub X} as an upper limit of the unobscured SFR to constrain the escape fraction of Ly{alpha} photons and find a lower limit of f{sub esc,Ly{alpha}} > 3%-10%. However, our upper limit on the SFR {sub X} is {approx}7 times larger than the upper limit on SFR {sub X} on z {approx} 3.1 LAEs in the same field and at least 30 times higher than the SFR estimated from Ly{alpha} emission. From the average X-ray-to-Ly{alpha} line ratio, we estimate that fewer than 3.2% (6.3%) of our LAEs could be high-redshift type 1 (type 2) active galactic nuclei (AGNs) and those hidden AGNs likely show low rest-frame EWs.

  8. A glimpse at quasar host galaxy far-UV emission using damped Ly?'s as natural coronagraphs

    SciTech Connect (OSTI)

    Cai, Zheng; Fan, Xiaohui; Wang, Ran; McGreer, Ian; Noterdaeme, Pasquier; Finley, Hayley; Petitjean, Patrick; Carithers, Bill; Bian, Fuyan; Miralda-Escud, Jordi; Pris, Isabelle; Schneider, Donald P.; Zakamska, Nadia L.; Ge, Jian; Slosar, Anze

    2014-10-01

    In merger-driven models of massive galaxy evolution, the luminous quasar phase is expected to be accompanied by vigorous star formation in quasar host galaxies. In this paper, we use high column density damped Ly? (DLA) systems along quasar sight lines as natural coronagraphs to directly study the far-UV (FUV) radiation from the host galaxies of luminous background quasars. We have stacked the spectra of ?2000 DLA systems (N {sub H} {sub I} > 10{sup 20.6} cm{sup 2}) with a median absorption redshift (z) = 2.6 selected from quasars observed in the SDSS-III Baryon Oscillation Spectroscopic Survey. We detect residual flux in the dark troughs of the composite DLA spectra. The level of this residual flux significantly exceeds systematic errors in the Sloan Digital Sky Survey fiber sky subtraction; furthermore, the residual flux is strongly correlated with the continuum luminosity of the background quasar, while uncorrelated with DLA column density or metallicity. We conclude that the flux could be associated with the average FUV radiation from the background quasar host galaxies (with medium redshift (z) = 3.1) that is not blocked by the intervening DLA. Assuming that all of the detected flux originates from quasar hosts, for the highest quasar luminosity bin ((L) = 2.5 10{sup 13} L {sub ?}), the host galaxy has an FUV intensity of 1.5 0.2 10{sup 40} erg s{sup 1} {sup 1}; this corresponds to an unobscured UV star formation rate of 9 M {sub ?} yr{sup 1}.

  9. DETECTIONS OF FAINT Ly{alpha} EMITTERS AT z = 5.7: GALAXY BUILDING BLOCKS AND ENGINES OF REIONIZATION

    SciTech Connect (OSTI)

    Dressler, Alan; McCarthy, Patrick; Martin, Crystal L.; Henry, Alaina; Sawicki, Marcin E-mail: sawicki@ap.smu.ca

    2011-10-20

    We report results of an unprecedentedly deep, blind search for Ly{alpha} emitters (LAEs) at z = 5.7 using the Inamori-Magellan Areal Camera and Spectrograph (IMACS), with the goal of identifying missing sources of reionization that could also be basic building blocks for today's L* galaxies. We describe how improvements in wide field imaging with the Baade telescope, upgrades to IMACS, and the accumulation of {approx}20 hr of integration per field in excellent seeing led to the detection of single-emission-line sources as faint as F {approx} 2 x 10{sup -18} erg s{sup -1} cm{sup -2}, a sensitivity five times deeper than our first search. A reasonable correction for foreground interlopers implies a steep rise of approximately an order of magnitude in source density for a factor of four drop in flux, from F = 10{sup -17.0} erg s{sup -1} cm{sup -2} to F = 10{sup -17.6} (2.5 x 10{sup -18}) erg s{sup -1} cm{sup -2}. At this flux the putative LAEs have reached a surface density of {approx}1 arcmin{sup -2}-a comoving volume density of 4 x 10{sup -3} Mpc{sup -3}, several times the density of L* galaxies today. Such a population of faint LAEs would account for a significant fraction of the critical flux density required to complete reionization at this epoch, and would be good candidates for building blocks of stellar mass {approx}10{sup 8}-10{sup 9} M{sub sun} for the young galaxies of this epoch.

  10. PHYSICAL PROPERTIES OF SPECTROSCOPICALLY CONFIRMED GALAXIES AT z {>=} 6. II. MORPHOLOGY OF THE REST-FRAME UV CONTINUUM AND Ly{alpha} EMISSION

    SciTech Connect (OSTI)

    Jiang Linhua; Windhorst, Rogier A.; Cohen, Seth H.; Mechtley, Matthew; Egami, Eiichi; Fan Xiaohui; Dave, Romeel; Finlator, Kristian; Kashikawa, Nobunari; Ouchi, Masami; Shimasaku, Kazuhiro

    2013-08-20

    We present a detailed structural and morphological study of a large sample of spectroscopically confirmed galaxies at z {>=} 6 using deep Hubble Space Telescope (HST) near-IR broad-band images and Subaru Telescope optical narrow-band images. The galaxy sample consists of 51 Ly{alpha} emitters (LAEs) at z {approx_equal} 5.7, 6.5, and 7.0, and 16 Lyman break galaxies (LBGs) at 5.9 {<=} z {<=} 6.5. These galaxies exhibit a wide range of rest-frame UV continuum morphology in the HST images, from compact features to multiple component systems. The fraction of merging/interacting galaxies reaches 40%-50% at the brightest end of M{sub 1500} {<=} -20.5 mag. The intrinsic half-light radii r{sub hl,in}, after correcting for point-spread function (PSF) broadening, are roughly between r{sub hl,in} {approx_equal} 0.''05 (0.3 kpc) and 0.''3 (1.7 kpc) at M{sub 1500} {<=} -19.5 mag. The median r{sub hl,in} value is 0.''16 ({approx}0.9 kpc). This is consistent with the sizes of bright LAEs and LBGs at z {>=} 6 found in previous studies. In addition, more luminous galaxies tend to be larger and exhibit a weak size-luminosity relation, r{sub hl,in}{proportional_to}L {sup 0.14} at M{sub 1500} {<=} -19.5 mag. The slope of 0.14 is significantly flatter than those in fainter LBG samples. We discuss the morphology of z {>=} 6 galaxies with nonparametric methods, including the concentration, asymmetry, and smoothness system and the Gini and M{sub 20} parameters, and demonstrate their validity through simulations. We search for extended Ly{alpha} emission halos around LAEs at z {approx_equal} 5.7 and 6.5 by stacking a number of narrow-band images. We do not find evidence of extended Ly{alpha} halos predicted by cosmological simulations. Such halos, if they exist, could be weaker than predicted. Finally, we investigate positional misalignment between the UV continuum and Ly{alpha} emissions in LAEs. While the two positions are generally consistent, several merging galaxies show significant positional differences. This is likely caused by a disturbed interstellar medium distribution due to merging activity.

  11. PHYSICAL PROPERTIES OF SPECTROSCOPICALLY CONFIRMED GALAXIES AT z {>=} 6. I. BASIC CHARACTERISTICS OF THE REST-FRAME UV CONTINUUM AND Ly{alpha} EMISSION

    SciTech Connect (OSTI)

    Jiang Linhua; Mechtley, Matthew; Cohen, Seth H.; Windhorst, Rogier A.; Egami, Eiichi; Fan Xiaohui; Dave, Romeel; Finlator, Kristian; Kashikawa, Nobunari; Ouchi, Masami; Shimasaku, Kazuhiro

    2013-08-01

    We present deep Hubble Space Telescope near-IR and Spitzer mid-IR observations of a large sample of spectroscopically confirmed galaxies at z {>=} 6. The sample consists of 51 Ly{alpha} emitters (LAEs) at z {approx_equal} 5.7, 6.5, and 7.0, and 16 Lyman break galaxies (LBGs) at 5.9 {<=} z {<=} 6.5. The near-IR images were mostly obtained with WFC3 in the F125W and F160W bands, and the mid-IR images were obtained with IRAC in the 3.6 {mu}m and 4.5 {mu}m bands. Our galaxies also have deep optical imaging data from Subaru Suprime-Cam. We utilize the multi-band data and secure redshifts to derive their rest-frame UV properties. These galaxies have steep UV-continuum slopes roughly between {beta} {approx_equal} -1.5 and -3.5, with an average value of {beta} {approx_equal} -2.3, slightly steeper than the slopes of LBGs in previous studies. The slope shows little dependence on UV-continuum luminosity except for a few of the brightest galaxies. We find a statistically significant excess of galaxies with slopes around {beta} {approx_equal} -3, suggesting the existence of very young stellar populations with extremely low metallicity and dust content. Our galaxies have moderately strong rest-frame Ly{alpha} equivalent width (EW) in a range of {approx}10 to {approx}200 A. The star formation rates are also moderate, from a few to a few tens of solar masses per year. The LAEs and LBGs in this sample share many common properties, implying that LAEs represent a subset of LBGs with strong Ly{alpha} emission. Finally, the comparison of the UV luminosity functions between LAEs and LBGs suggests that there exists a substantial population of faint galaxies with weak Ly{alpha} emission (EW < 20 A) that could be the dominant contribution to the total ionizing flux at z {>=} 6.

  12. filekLyDib

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

  13. Living SafeLy

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

    as safe as the electrical wiring in our homes - or just as danger- ous. The key is learning to act safely around them. This booklet is a basic safety guide for those who live...

  14. Intergalactic medium emission observations with the cosmic web imager. II. Discovery of extended, kinematically linked emission around SSA22 Ly? BLOB 2

    SciTech Connect (OSTI)

    Christopher Martin, D.; Chang, Daphne; Matuszewski, Matt; Morrissey, Patrick; Rahman, Shahin; Moore, Anna; Steidel, Charles C.; Matsuda, Yuichi

    2014-05-10

    The intergalactic medium (IGM) is the dominant reservoir of baryons, delineates the large-scale structure of the universe at low to moderate overdensities, and provides gas from which galaxies form and evolve. Simulations of a cold-dark-matter- (CDM-) dominated universe predict that the IGM is distributed in a cosmic web of filaments and that galaxies should form along and at the intersections of these filaments. While observations of QSO absorption lines and the large-scale distribution of galaxies have confirmed the CDM paradigm, the cosmic web of IGM has never been confirmed by direct imaging. Here we report our observation of the Ly? blob 2 (LAB2) in SSA22 with the Cosmic Web Imager (CWI). This is an integral field spectrograph optimized for low surface brightness, extended emission. With 22 hr of total on- and off-source exposure, CWI has revealed that LAB2 has extended Ly? emission that is organized into azimuthal zones consistent with filaments. We perform numerous tests with simulations and the data to secure the robustness of this result, which relies on data with modest signal-to-noise ratios. We have developed a smoothing algorithm that permits visualization of data cube slices along image or spectral image planes. With both raw and smoothed data cubes we demonstrate that the filaments are kinematically associated with LAB2 and display double-peaked profiles characteristic of optically thick Ly? emission. The flux is 10-20 times brighter than expected for the average emission from the IGM but is consistent with boosted fluorescence from a buried QSO or gravitation cooling radiation. Using simple emission models, we infer a baryon mass in the filaments of at least 1-4 10{sup 11} M {sub ?}, and the dark halo mass is at least 2 10{sup 12} M {sub ?}. The spatial-kinematic morphology is more consistent with inflow from the cosmic web than outflow from LAB2, although an outflow feature maybe present at one azimuth. LAB2 and the surrounding gas have significant and coaligned angular momentum, strengthening the case for their association.

  15. An HST/COS observation of broad Ly? emission and associated absorption lines of the BL Lacertae object H 2356-309

    SciTech Connect (OSTI)

    Fang, Taotao [Department of Astronomy and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen, Fujian 361005 (China); Danforth, Charles W.; Stocke, John T.; Shull, J. Michael [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, 389-UCB, Boulder, CO 80309 (United States); Buote, David A. [Department of Physics and Astronomy, 4129 Frederick Reines Hall, University of California, Irvine, CA 92697 (United States); Canizares, Claude R. [Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Gastaldello, Fabio, E-mail: fangt@xmu.edu.cn [IASF-Milano, INAF, via Bassini 15, Milan I-20133 (Italy)

    2014-11-01

    Weak spectral features in BL Lacertae objects (BL Lacs) often provide a unique opportunity to probe the inner region of this rare type of active galactic nucleus. We present a Hubble Space Telescope/Cosmic Origins Spectrograph observation of the BL Lac H 2356-309. A weak Ly? emission line was detected. This is the fourth detection of a weak Ly? emission feature in the ultraviolet (UV) band in the so-called high-energy peaked BL Lacs, after Stocke et al. Assuming the line-emitting gas is located in the broad line region (BLR) and the ionizing source is the off-axis jet emission, we constrain the Lorentz factor (?) of the relativistic jet to be ?8.1 with a maximum viewing angle of 3.6. The derived ? is somewhat larger than previous measurements of ? ? 3-5, implying a covering factor of ?3% of the line-emitting gas. Alternatively, the BLR clouds could be optically thin, in which case we constrain the BLR warm gas to be ?10{sup 5} M {sub ?}. We also detected two H I and one O VI absorption lines that are within |?v| < 150 km s{sup 1} of the BL Lac object. The O VI and one of the H I absorbers likely coexist due to their nearly identical velocities. We discuss several ionization models and find a photoionization model where the ionizing photon source is the BL Lac object that can fit the observed ion column densities with reasonable physical parameters. This absorber can either be located in the interstellar medium of the host galaxy or in the BLR.

  16. Radiation damage and associated phase change effect on photodesorption rates from icesLy? studies of the surface behavior of CO{sub 2}(ice)

    SciTech Connect (OSTI)

    Yuan, Chunqing; Yates, John T. Jr.

    2014-01-01

    Photodesorption from a crystalline film of CO{sub 2}(ice) at 75 K has been studied using Ly? (10.2 eV) radiation. We combine quantitative mass spectrometric studies of gases evolved and transmission IR studies of species trapped in the ice. Direct CO desorption is observed from the primary CO{sub 2} photodissociation process, which occurs promptly for CO{sub 2} molecules located on the outermost surface of the ice (Process I). As the fluence of Ly? radiation increases to ?5.5 10{sup 17} photons cm{sup 2}, extensive damage to the crystalline ice occurs and photo-produced CO molecules from deeper regions (Process II) are found to desorb at a rapidly increasing rate, which becomes two orders of magnitude greater than Process I. It is postulated that deep radiation damage to produce an extensive amorphous phase of CO{sub 2} occurs in the 50 nm ice film and that CO (and CO{sub 2}) diffusive transport is strongly enhanced in the amorphous phase. Photodesorption in Process II is a combination of electronic and thermally activated processes. Radiation damage in crystalline CO{sub 2} ice has been monitored by its effects on the vibrational line shapes of CO{sub 2}(ice). Here the crystalline-to-amorphous phase transition has been correlated with the occurrence of efficient molecular transport over long distances through the amorphous phase of CO{sub 2}(ice). Future studies of the composition of the interstellar region, generated by photodesorption from ice layers on grains, will have to consider the significant effects of radiation damage on photodesorption rates.

  17. STELLAR POPULATIONS OF Ly{alpha} EMITTERS AT z {approx} 6-7: CONSTRAINTS ON THE ESCAPE FRACTION OF IONIZING PHOTONS FROM GALAXY BUILDING BLOCKS

    SciTech Connect (OSTI)

    Ono, Yoshiaki; Shimasaku, Kazuhiro; Okamura, Sadanori; Masami Ouchi; Dunlop, James; Farrah, Duncan; McLure, Ross

    2010-12-01

    We investigate the stellar populations of Ly{alpha} emitters (LAEs) at z = 5.7 and 6.6 in a 0.65 deg{sup 2} sky of the Subaru/XMM-Newton Deep Survey (SXDS) Field, using deep images taken with the Subaru/Suprime-Cam, United Kingdom Infrared Telescope/Wide Field Infrared Camera, and Spitzer/Infrared Array Camera (IRAC). We produce stacked multiband images at each redshift from 165 (z = 5.7) and 91 (z = 6.6) IRAC-undetected objects to derive typical spectral energy distributions (SEDs) of z {approx} 6-7 LAEs for the first time. The stacked LAEs have as blue UV continua as the Hubble Space Telescope (HST)/Wide Field Camera 3 (WFC3) z-dropout galaxies of similar M{sub UV}, with a spectral slope {beta} {approx} -3, but at the same time they have red UV-to-optical colors with detection in the 3.6 {mu}m band. Using SED fitting we find that the stacked LAEs have low stellar masses of {approx}(3-10) x 10{sup 7} M{sub sun}, very young ages of {approx}1-3 Myr, negligible dust extinction, and strong nebular emission from the ionized interstellar medium, although the z = 6.6 object is fitted similarly well with high-mass models without nebular emission; inclusion of nebular emission reproduces the red UV-to-optical colors while keeping the UV colors sufficiently blue. We infer that typical LAEs at z {approx} 6-7 are building blocks of galaxies seen at lower redshifts. We find a tentative decrease in the Ly{alpha} escape fraction from z = 5.7 to 6.6, which may imply an increase in the intergalactic medium neutral fraction. From the minimum contribution of nebular emission required to fit the observed SEDs, we place an upper limit on the escape fraction of ionizing photons of f {sup ion}{sub esc} {approx} 0.6 at z = 5.7 and {approx}0.9 at z = 6.6. We also compare the stellar populations of our LAEs with those of stacked HST/WFC3 z-dropout galaxies.

  18. HM-ACCESS Project | Department of Energy

    Office of Environmental Management (EM)

    Office of Packaging and Transportation Fiscal Year 2012 Annual Report Controlling Methane Emissions in the Natural Gas Sector: A Review of Federal & State Regulatory...

  19. THE FIRST OBSERVATIONS OF LOW-REDSHIFT DAMPED Ly{alpha} SYSTEMS WITH THE COSMIC ORIGINS SPECTROGRAPH: CHEMICAL ABUNDANCES AND AFFILIATED GALAXIES

    SciTech Connect (OSTI)

    Battisti, A. J.; Meiring, J. D.; Tripp, T. M. [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States); Prochaska, J. X.; Werk, J. K. [Department of Astronomy and Astrophysics, University of California Observatories-Lick Observatory, UC Santa Cruz, CA 95064 (United States); Jenkins, E. B. [Department of Astrophysical Sciences, Princeton University Observatory, Princeton, NJ 08544 (United States); Lehner, N. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Tumlinson, J.; Thom, C. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

    2012-01-10

    We present Cosmic Origins Spectrograph (COS) measurements of metal abundances in eight 0.083 < z{sub abs} < 0.321 damped Ly{alpha} (DLA) and sub-DLA absorption systems serendipitously discovered in the COS-Halos survey. We find that these systems show a large range in metallicities, with -1.10 < [Z/H] < 0.31, similar to the spread found at higher redshifts. These low-redshift systems on average have subsolar metallicities, but do show a rise in metallicity over cosmic time when compared to higher-redshift systems. We find that the average sub-DLA metallicity is higher than the average DLA metallicity at all redshifts. Nitrogen is underabundant with respect to {alpha}-group elements in all but perhaps one of the absorbers. In some cases, [N/{alpha}] is significantly below the lowest nitrogen measurements in nearby galaxies. Systems for which depletion patterns can be studied show little, if any, depletion, which is characteristic of Milky Way halo-type gas. We also identify affiliated galaxies for three of the sub-DLAs using spectra obtained from a Keck/Low Resolution Imaging Spectrometer (LRIS). None of these sub-DLAs arise in the stellar disks of luminous galaxies; instead, these absorbers may exist in galaxy halos at impact parameters ranging from 38 to 92 kpc. Multiple galaxies are present near two of the sub-DLAs, and galaxy interactions may play a role in the dispersal of the gas. Many of these low-redshift absorbers exhibit simple kinematics, but one sub-DLA has a complicated mix of at least 13 components spread over 150 km s{sup -1}. We find three galaxies near this sub-DLA, which also suggests that galaxy interactions roil the gas. This study reinforces the view that DLAs have a variety of origins, and low-redshift studies are crucial for understanding absorber-galaxy connections.

  20. S A N D I A T E C H N O L O G Y A Q UA RT E R LY R E S E A R

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

    Summer in Antarctica Ice in nanoseconds SUMMER 2007 S A N D I A T E C H N O L O G Y A Q UA RT E R LY R E S E A R C H & D E V E LO P M E N T MAG A Z I N E - VO LUM E 9 , N O. 2 Drought dilemmas Sandia Technology (ISSN: 1547-5190) is a quarterly magazine published by Sandia National Laboratories. Sandia is a mul- tiprogram engineering and science laboratory operated by Sandia Corporation, a Lockheed Martin company, for the U.S. Department of Energy. With main facilities in Albuquerque, New

  1. S A N D I A T E C H N O L O G Y A Q UA RT E R LY R E S E A R

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

    Closer to fusion Biofuels on tap FALL 2007 S A N D I A T E C H N O L O G Y A Q UA RT E R LY R E S E A R C H & D E V E LO P M E N T MAG A Z I N E - VO LUM E 9 , N O. 3 Simulation: Making engineers better Sandia Technology (ISSN: 1547-5190) is a quarterly maga- zine published by Sandia National Laboratories. Sandia is a multiprogram engineering and science laboratory operated by Sandia Corporation, a Lockheed Martin company, for the U.S. Department of Energy. With main facilities in

  2. METALLICITIES, DUST, AND MOLECULAR CONTENT OF A QSO-DAMPED Ly{alpha} SYSTEM REACHING log N(H I) = 22: AN ANALOG TO GRB-DLAs

    SciTech Connect (OSTI)

    Guimaraes, R.; Noterdaeme, P.; Petitjean, P.; Ledoux, C.; Srianand, R.; Rahmani, H.; Lopez, S.

    2012-06-15

    We present the elemental abundance and H{sub 2} content measurements of a damped Ly{alpha} (DLA) system with an extremely large H I column density, log N(H I) (cm{sup -2}) = 22.0 {+-} 0.10, at z{sub abs} = 3.287 toward the QSO SDSS J081634+144612. We measure column densities of H{sub 2}, C I, C I*, Zn II, Fe II, Cr II, Ni II, and Si II from a high signal-to-noise and high spectral resolution VLT-UVES spectrum. The overall metallicity of the system is [Zn/H] = -1.10 {+-} 0.10 relative to solar. Two molecular hydrogen absorption components are seen at z = 3.28667 and 3.28742 (a velocity separation of Almost-Equal-To 52 km s{sup -1}) in rotational levels up to J = 3. We derive a total H{sub 2} column density of log N(H{sub 2}) (cm{sup -2}) = 18.66 and a mean molecular fraction of f = 2N(H{sub 2})/[2N(H{sub 2}) + N(H I)] = 10{sup -3.04{+-}0.37}, typical of known H{sub 2}-bearing DLA systems. From the observed abundance ratios we conclude that dust is present in the interstellar medium of this galaxy, with an enhanced abundance in the H{sub 2}-bearing clouds. However, the total amount of dust along the line of sight is not large and does not produce any significant reddening of the background QSO. The physical conditions in the H{sub 2}-bearing clouds are constrained directly from the column densities of H{sub 2} in different rotational levels, C I and C I*. The kinetic temperature is found to be T Almost-Equal-To 75 K and the particle density lies in the range n{sub H} = 50-80 cm{sup -3}. The neutral hydrogen column density of this DLA is similar to the mean H I column density of DLAs observed at the redshift of {gamma}-ray bursts (GRBs). We explore the relationship between GRB-DLAs and the high column density end of QSO-DLAs finding that the properties (metallicity and depletion) of DLAs with log N(H I) > 21.5 in the two populations do not appear to be significantly different.

  3. Libya: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Natural Gas Reserves 1,539,000,000,000 Cubic Meters (cu m) 23 2010 CIA World Factbook Oil Reserves 47,000,000,000 Barrels (bbl) 9 2010 CIA World Factbook Energy Maps featuring...

  4. S A N D I A T E C H N O L O G Y A Q UA RT E R LY R E S E A R

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

    Record-setting solar power Green jet fuel SUMMER 2008 In this issue: S A N D I A T E C H N O L O G Y A Q UA RT E R LY R E S E A R C H & D E V E LO P M E N T MAG A Z I N E - VO LUM E 1 0 , N O. 1 Energized Sandia Technology (ISSN: 1547-5190) is a quarterly maga- zine published by Sandia National Laboratories. Sandia is a multiprogram engineering and science laboratory operated by Sandia Corporation, a Lockheed Martin company, for the U.S. Department of Energy. With main facilities in

  5. Tru-ly Clean - What Does It Mean?

    SciTech Connect (OSTI)

    Hopkins, A.

    2008-07-01

    The evolution and genesis of the definition of transuranic waste (known as TRU) and its application to the cleanup criteria applied to soils contaminated with transuranics, specifically plutonium, has been a matter of discussion at contaminated sites in the United States and elsewhere. Cleanup decisions and the processes that led up to those decisions have varied at several plutonium contaminated sites within the United States and without the pacific region. The sites with radionuclide soil action levels include Bikini and Enewetak Atolls, Republic of the Marshall Islands; Johnston Atoll, Hawaii; the Hanford Site in Washington State; the Nevada Test Site; the Rocky Flats Environmental Technology Site in Colorado; the Chariot Site in north Alaska; and the Maralinga Site in Australia. The soil-action level developed for Rocky Flats by the U.S. Department of Energy, U.S. Environmental Protection Agency, and the Colorado Department of Public Health and Environment for plutonium is one of the higher soil-action levels approved by regulatory agencies that is considered protective for future use of land at a cleanup site. The Republic of the Marshall Islands has adopted a relatively conservative cleanup standard to accommodate the subsistence lifestyle of the islanders, while the Rocky Flats Environmental Technology Site has been transferred to the U.S. Department of the Interior to be used as a fish and wildlife refuge, a land use that resulted in a less conservative plutonium soil cleanup level. (authors)

  6. Estimated use of explosives in the mining industries of Algeria, Iran, Iraq, and Libya

    SciTech Connect (OSTI)

    Wilburn, D.R.; Russell, J.A.; Bleiwas, D.I.

    1995-09-01

    This work was performed under Memorandum of Agreement B291534 Between the Lawrence Livermore National Laboratory (LLNL) and the United States Bureau of Mines. The Bureau of Mines authors are members of the Minerals Availability Field Office (MAFO) in Denver, CO, which uses an extensive network of information sources to develop and maintain the Minerals Availability database concerning mining and minerals properties worldwide. This study was initiated and directed by F. Heuze at LLNL. A previous study on the same subject had been commissioned by LLNL from the Mining Journal Research Services (MJRS) in London ,UK. Its results were integrated into this report. MJRS is shown as one of the numerous sources which were used for this work. All sources are listed in the report. This document is arranged in four sections, one for each country, in alphabetical order. Thie outline is the same for each country.

  7. Ly{alpha} EMITTERS AT z = 7 IN THE SUBARU/XMM-NEWTON DEEP SURVEY...

    Office of Scientific and Technical Information (OSTI)

    AND LUMINOSITY FUNCTION Citation Details In-Document Search Title: Lyalpha EMITTERS AT z 7 IN THE SUBARUXMM-NEWTON DEEP SURVEY FIELD: PHOTOMETRIC CANDIDATES AND LUMINOSITY ...

  8. IGM CONSTRAINTS FROM THE SDSS-III/BOSS DR9 Ly? FOREST TRANSMISSION...

    Office of Scientific and Technical Information (OSTI)

    SPACE; LIMITING VALUES; LYMAN LINES; NOISE; OSCILLATIONS; PROBABILITY; QUASARS; RED SHIFT; UNIVERSE Word Cloud More Like This Full Text Journal Articles DOI: 10.1088...

  9. SEARCHING FOR z {approx} 7.7 Ly{alpha} EMITTERS IN THE COSMOS...

    Office of Scientific and Technical Information (OSTI)

    GALACTIC EVOLUTION; GALAXIES; HYDROGEN; LUMINOSITY; MASS; MONTE CARLO METHOD; RED SHIFT; STARS; TELESCOPES; UNIVERSE Word Cloud More Like This Full Text Journal Articles...

  10. THE END OF HELIUM REIONIZATION AT z {approx_equal} 2.7 INFERRED FROM COSMIC VARIANCE IN HST/COS He II Ly{alpha} ABSORPTION SPECTRA

    SciTech Connect (OSTI)

    Worseck, Gabor; Xavier Prochaska, J. [Department of Astronomy and Astrophysics, UCO/Lick Observatory, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States); McQuinn, Matthew [Department of Astronomy, University of California, 601 Campbell Hall, Berkeley, CA 94720 (United States); Dall'Aglio, Aldo; Wisotzki, Lutz [Astrophysikalisches Institut Potsdam, An der Sternwarte 16, 14482 Potsdam (Germany); Fechner, Cora; Richter, Philipp [Institut fuer Physik und Astronomie, Universitaet Potsdam, Karl-Liebknecht-Str. 24/25, 14476 Potsdam (Germany); Hennawi, Joseph F. [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, 69117 Heidelberg (Germany); Reimers, Dieter, E-mail: gworseck@ucolick.org [Hamburger Sternwarte, Universitaet Hamburg, Gojenbergsweg 112, 21029 Hamburg (Germany)

    2011-06-01

    We report on the detection of strongly varying intergalactic He II absorption in HST/COS spectra of two z{sub em} {approx_equal} 3 quasars. From our homogeneous analysis of the He II absorption in these and three archival sightlines, we find a marked increase in the mean He II effective optical depth from <{tau}{sub eff},He{sub ii}>{approx_equal}1 at z {approx_equal} 2.3 to <{tau}{sub eff},He{sub ii}>{approx}>5 at z {approx_equal} 3.2, but with a large scatter of 2{approx}<{tau}{sub eff},He{sub ii}{approx}<5 at 2.7 < z < 3 on scales of {approx}10 proper Mpc. This scatter is primarily due to fluctuations in the He II fraction and the He II-ionizing background, rather than density variations that are probed by the coeval H I forest. Semianalytic models of He II absorption require a strong decrease in the He II-ionizing background to explain the strong increase of the absorption at z {approx}> 2.7, probably indicating He II reionization was incomplete at z{sub reion} {approx}> 2.7. Likewise, recent three-dimensional numerical simulations of He II reionization qualitatively agree with the observed trend only if He II reionization completes at z{sub reion} {approx_equal} 2.7 or even below, as suggested by a large {tau}{sub eff},He{sub ii}{approx}>3 in two of our five sightlines at z < 2.8. By doubling the sample size at 2.7 {approx}< z {approx}< 3, our newly discovered He II sightlines for the first time probe the diversity of the second epoch of reionization when helium became fully ionized.

  11. Halo mass dependence of H I and O VI absorption: evidence for differential kinematics

    SciTech Connect (OSTI)

    Mathes, Nigel L.; Churchill, Christopher W.; Nielsen, Nikole M.; Trujillo-Gomez, Sebastian [New Mexico State University, Las Cruces, NM 88003 (United States); Kacprzak, Glenn G. [Swinburne University of Technology, Victoria 3122 (Australia); Charlton, Jane; Muzahid, Sowgat [The Pennsylvania State University, University Park, PA 16802 (United States)

    2014-09-10

    We studied a sample of 14 galaxies (0.1 < z < 0.7) using HST/WFPC2 imaging and high-resolution HST/COS or HST/STIS quasar spectroscopy of Ly?, Ly?, and O VI ??1031, 1037 absorption. The galaxies, having 10.8 ? log (M {sub h}/M {sub ?}) ? 12.2, lie within D = 300 kpc of quasar sightlines, probing out to D/R {sub vir} = 3. When the full range of M {sub h} and D/R {sub vir} of the sample are examined, ?40% of the H I absorbing clouds can be inferred to be escaping their host halo. The fraction of bound clouds decreases as D/R {sub vir} increases such that the escaping fraction is ?15% for D/R {sub vir} < 1, ?45% for 1 ? D/R {sub vir} < 2, and ?90% for 2 ? D/R {sub vir} < 3. Adopting the median mass log M {sub h}/M {sub ?} = 11.5 to divide the sample into 'higher' and 'lower' mass galaxies, we find a mass dependency for the hot circumgalactic medium kinematics. To our survey limits, O VI absorption is found in only ?40% of the H I clouds in and around lower mass halos as compared to ?85% around higher mass halos. For D/R {sub vir} < 1, lower mass halos have an escape fraction of ?65%, whereas higher mass halos have an escape fraction of ?5%. For 1 ? D/R {sub vir} < 2, the escape fractions are ?55% and ?35% for lower mass and higher mass halos, respectively. For 2 ? D/R {sub vir} < 3, the escape fraction for lower mass halos is ?90%. We show that it is highly likely that the absorbing clouds reside within 4R {sub vir} of their host galaxies and that the kinematics are dominated by outflows. Our finding of 'differential kinematics' is consistent with the scenario of 'differential wind recycling' proposed by Oppenheimer et al. We discuss the implications for galaxy evolution, the stellar to halo mass function, and the mass-metallicity relationship of galaxies.

  12. WorldWide Science.org

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

    Estonia Ethiopia Finland France Germany Ghana Greece Honduras India Indonesia Ireland Italy Japan Kenya Latvia Lesotho Libya Lithuania Madagascar Malawi Malaysia Mauritius Mexico ...

  13. This Week In Petroleum Summary Printer-Friendly Version

    Gasoline and Diesel Fuel Update (EIA)

    and political pressures that have already curtailed output. Libya's precarious security environment creates downside production risk from the potential for additional disruptions...

  14. Microsoft PowerPoint - 1_Cruz_Import Export_NMMSS 2013 Presentation...

    National Nuclear Security Administration (NNSA)

    to restricted destinations - a specific license may be required: Afghanistan Andorra Angola Burma Djibouti India Israel Libya Pakistan South Sudan 12 Nameaddress of...

  15. Fact #578: July 6, 2009 World Oil Reserves, Production, and Consumptio...

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

    Supporting Information World Oil Reserves, Production, and Consumption, 2007 Crude oil ... United Arab Emirates, Algeria, Libya, Nigeria, Indonesia, Gabon, and Ecuador. OPEC ...

  16. Shipping and Receiving

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

    shipping should be used at all other times. Shipping materials to Cuba, Iran, Libya, North Korea, Sudan, and Syria is prohibited; contact Berkeley Lab Procurement for more...

  17. Shipping and Receiving

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

    necessary; regular shipping should be used at all other times. Shipping materials to Cuba, Iran, Libya, North Korea, Sudan, and Syria is prohibited; contact Berkeley Lab...

  18. Costs of Imported Crude Oil by Selected Country

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Baharain, Iran, Iraq, Kuwait, Neutral Zone, Qatar, Saudi Arabia, and United Arab Emirates. c Includes Algeria, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi...

  19. untitled

    Gasoline and Diesel Fuel Update (EIA)

    Baharain, Iran, Iraq, Kuwait, Neutral Zone, Qatar, Saudi Arabia, and United Arab Emirates. c Includes Algeria, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi...

  20. untitled

    Gasoline and Diesel Fuel Update (EIA)

    Baharain, Iran, Iraq, Kuwait, Neutral Zone, Qatar, Saudi Arabia, and United Arab Emirates. b Includes Algeria, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi...

  1. Table 25. Landed Costs of Imported Crude Oil by Selected Country

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Baharain, Iran, Iraq, Kuwait, Neutral Zone, Qatar, Saudi Arabia, and United Arab Emirates. b Includes Algeria, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi...

  2. Table Definitions, Sources, and Explanatory Notes

    Gasoline and Diesel Fuel Update (EIA)

    Gulf Includes Bahrain, Iran, Iraq, Kuwait, Qatar, Saudi Arabia, and the United Arab Emirates. Total OPEC Includes Algeria, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar,...

  3. This Week In Petroleum Summary Printer-Friendly Version

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    that it will respect existing contracts, IOCs seeking to purchase oil from Libya or invest in the country's oil sector must be able to identify their institutional and financial...

  4. This Week In Petroleum Summary Printer-Friendly Version

    Gasoline and Diesel Fuel Update (EIA)

    in July, down from 1.5 million bbld in April. Additional deterioration in the security environment in Iraq or Libya could further reduce OPEC production in the short term. In...

  5. The Availability and Price of Petroleum and Petroleum Products...

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

    by an average of 0.8 million bbld in September and October 2013. Increased global crude oil production, particularly from Libya and Iraq, in the past two months, at a time when...

  6. The Availability and Price of Petroleum and Petroleum Products...

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

    boosted global liquid fuels production relative to year-ago levels. However, OPEC crude oil production decreased slightly from year-ago levels, as production gains in Libya and...

  7. Measuring the Costs of U.S. Oil Dependence and the Benefits of...

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

    exporters operating as OPEC." Prof. M. Adelman, MIT, 2004. Algeria Angola Ecuador Iran Iraq Kuwait Libya Nigeria Qatar Saudi Arabia UAE Venezuela 0 20 40 60 80 100 120...

  8. ,"U.S. Total Crude Oil and Products Imports"

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

    from Libya of Crude Oil and Petroleum Products (Thousand Barrels)","U.S. Imports from Nigeria of Crude Oil and Petroleum Products (Thousand Barrels)","U.S. Imports from Qatar of...

  9. This Week In Petroleum Summary Printer-Friendly Version

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    of political unrest in North Africa, including violent uprisings in Libya that have led to the shutdown of much of its oil production. The spot prices for West Texas...

  10. Section J - K: Documents, Exhibits, and Other Attachments

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

    ... Korea (Democratic People's Republic of) - Terrorist Section J - Page 13 of 27 Request for Proposal DE-RP36-07GO97036 Kyrgyzstan Libya - Terrorist Moldavia Pakistan Russia ...

  11. Slide 1

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

    The Integrated World Oil Market 0 20 40 60 80 100 120 140 0 20 40 60 80 100 120 140 Sidi Kerir Iran Light Libya Es Sider Libyan and Iranian Prices per barrel, 1979 - 2009 300 ...

  12. East Coast Utilities prepare for Hurricane Sandy | OpenEI Community

    Open Energy Info (EERE)

    Please report your outage to 1-800-833-7476, http:bit.lywbqiUb or through our mobile app at http:bit.lyL3Bvs4 . Please check our outage map for updates: http:bit.ly...

  13. Spring 2015 Henderson Hall Education and Career Fair

    Broader source: Energy.gov [DOE]

    Location: Smith Gym, Henderson Hall, Arlington, VAPOC: DOECorporateRecruitment@hq.doe.govWebsite: http://bit.ly/1FRIJOF

  14. Anisotropic Lyman-alpha emission

    SciTech Connect (OSTI)

    Zheng, Zheng; Wallace, Joshua

    2014-10-20

    As a result of resonant scatterings off hydrogen atoms, Ly? emission from star-forming galaxies provides a probe of the (hardly isotropic) neutral gas environment around them. We study the effect of the environmental anisotropy on the observed Ly? emission by performing radiative transfer calculations for models of neutral hydrogen clouds with prescriptions of spatial and kinematic anisotropies. The environmental anisotropy leads to corresponding anisotropy in the Ly? flux and spectral properties and induces correlations among them. The Ly? flux (or observed luminosity) depends on the viewing angle and shows an approximate correlation with the initial Ly? optical depth in the viewing direction relative to those in all other directions. The distribution of Ly? flux from a set of randomly oriented clouds is skewed to high values, providing a natural contribution to the Ly? equivalent width (EW) distribution seen in observation. A narrower EW distribution is found at a larger peak offset of the Ly? line, similar to the trend suggested in observation. The peak offset appears to correlate with the line shape (full width at half-maximum and asymmetry), pointing to a possibility of using Ly? line features alone to determine the systemic redshifts of galaxies. The study suggests that anisotropies in the spatial and kinematic distributions of neutral hydrogen can be an important ingredient in shaping the observed properties of Ly? emission from star-forming galaxies. We discuss the implications of using Ly? emission to probe the circumgalactic and intergalactic environments of galaxies.

  15. The Lyman alpha reference sample. II. Hubble space telescope imaging results, integrated properties, and trends

    SciTech Connect (OSTI)

    Hayes, Matthew; stlin, Gran; Duval, Florent; Sandberg, Andreas; Guaita, Lucia; Melinder, Jens; Rivera-Thorsen, Thger; Adamo, Angela; Schaerer, Daniel; Verhamme, Anne; Orlitov, Ivana; Mas-Hesse, J. Miguel; Ot-Floranes, Hctor; Cannon, John M.; Pardy, Stephen; Atek, Hakim; Kunth, Daniel; Laursen, Peter; Herenz, E. Christian

    2014-02-10

    We report new results regarding the Ly? output of galaxies, derived from the Lyman Alpha Reference Sample, and focused on Hubble Space Telescope imaging. For 14 galaxies we present intensity images in Ly?, H?, and UV, and maps of H?/H?, Ly? equivalent width (EW), and Ly?/H?. We present Ly? and UV radial light profiles and show they are well-fitted by Srsic profiles, but Ly? profiles show indices systematically lower than those of the UV (n ? 1-2 instead of ? 4). This reveals a general lack of the central concentration in Ly? that is ubiquitous in the UV. Photometric growth curves increase more slowly for Ly? than the far ultraviolet, showing that small apertures may underestimate the EW. For most galaxies, however, flux and EW curves flatten by radii ?10 kpc, suggesting that if placed at high-z only a few of our galaxies would suffer from large flux losses. We compute global properties of the sample in large apertures, and show total Ly? luminosities to be independent of all other quantities. Normalized Ly? throughput, however, shows significant correlations: escape is found to be higher in galaxies of lower star formation rate, dust content, mass, and nebular quantities that suggest harder ionizing continuum and lower metallicity. Six galaxies would be selected as high-z Ly? emitters, based upon their luminosity and EW. We discuss the results in the context of high-z Ly? and UV samples. A few galaxies have EWs above 50 , and one shows f{sub esc}{sup Ly?} of 80%; such objects have not previously been reported at low-z.

  16. Energy level structure and transition probabilities in the spectra...

    Office of Scientific and Technical Information (OSTI)

    H.M. 74 ATOMIC AND MOLECULAR PHYSICS; 36 MATERIALS SCIENCE; DYSPROSIUM IONS; ENERGY LEVELS; ERBIUM IONS; EUROPIUM IONS; GADOLINIUM IONS; HOLMIUM IONS; LANTHANUM...

  17. Oil and gas developments in North Africa in 1986

    SciTech Connect (OSTI)

    Michel, R.C.

    1987-10-01

    Licensed oil acreage in the 6 North Africa countries (Algeria, Egypt, Libya, Morocco, Sudan and Tunisia) totaled 1,500,000 km/sup 2/ at the end of 1986, down 290,000 km/sup 2/ from 1985. About 50% of the relinquishments were in Libya. Most oil and gas discoveries were made in Egypt (16 oil and 2 gas). Several oil finds were reported in onshore Libya, and 1 was reported in Algeria in the southeastern Sahara. According to available statistics, development drilling decreased from 1985 levels, except in Tunisia. A 6.3% decline in oil production took place in 1986, falling below the 3 million bbl level (2,912,000 b/d). Only sparse data are released on the gas output in North Africa. 6 figures, 27 tables.

  18. Narrowband Lyman-continuum imaging of galaxies at z ? 2.85

    SciTech Connect (OSTI)

    Mostardi, R. E.; Shapley, A. E.; Nestor, D. B.; Steidel, C. C.; Trainor, R. F.; Reddy, N. A.

    2013-12-10

    We present results from a survey for z ? 2.85 Lyman-continuum (LyC) emission in the HS1549+1933 field and place constraints on the amount of ionizing radiation escaping from star-forming galaxies. Using a custom narrowband filter (NB3420) tuned to wavelengths just below the Lyman limit at z ? 2.82, we probe the LyC spectral region of 49 Lyman break galaxies (LBGs) and 91 Ly? emitters (LAEs) spectroscopically confirmed at z ? 2.82. Four LBGs and seven LAEs are detected in NB3420. Using V-band data probing the rest-frame nonionizing UV, we observe that many NB3420-detected galaxies exhibit spatial offsets between their LyC and nonionizing UV emission and are characterized by extremely blue NB3420V colors, corresponding to low ratios of nonionizing to ionizing radiation (F {sub UV}/F {sub LyC}) that are in tension with current stellar population synthesis models. We measure average values of (F {sub UV}/F {sub LyC}) for our LBG and LAE samples, correcting for foreground galaxy contamination and H I absorption in the intergalactic medium. We find (F{sub UV}/F{sub LyC}){sub corr}{sup LBG}=8245 and (F{sub UV}/F{sub LyC}){sub corr}{sup LAE}=7.43.6. These flux density ratios correspond, respectively, to relative LyC escape fractions of f{sub esc,} {sub rel}{sup LBG}=5%--8% and f{sub esc,} {sub rel}{sup LAE}=18%--49%, absolute LyC escape fractions of f{sub esc}{sup LBG}=1%--2% and f{sub esc}{sup LAE}=5%--15%, and a comoving LyC emissivity from star-forming galaxies of 8.8-15.0 10{sup 24} erg s{sup 1} Hz{sup 1} Mpc{sup 3}. In order to study the differential properties of galaxies with and without LyC detections, we analyze narrowband Ly? imaging and rest-frame near-infrared imaging, finding that while LAEs with LyC detections have lower Ly? equivalent widths on average, there is no substantial difference in the rest-frame near-infrared colors of LBGs or LAEs with and without LyC detections. These preliminary results are consistent with an orientation-dependent model where LyC emission escapes through cleared paths in a patchy interstellar medium.

  19. Microsoft Word - Highlights.doc

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

    11 1 Short-Term Energy Outlook March 2011 March 8, 2011 Release Highlights  West Texas Intermediate (WTI) and other crude oil spot prices have risen about $15 per barrel since mid-February partly in response to the disruption of crude oil exports from Libya. Continuing unrest in Libya as well as other North African and Middle Eastern countries has led to the highest crude oil prices since 2008. As a result, EIA has raised its forecast for the average cost of crude oil to refiners to $105 per

  20. VTKADIOSSCHEMAREADER

    Energy Science and Technology Software Center (OSTI)

    003354WKSTN00 ADIOS Schema reader for VTK https://www.dropbox.com/s/ly94k82xdd41hyi/AdiosSchemaReader-master.zip

  1. Black Engineering of the Year Awards and STEM Conference Career Fair

    Broader source: Energy.gov [DOE]

    Location: Washington Marriott Wardman Park, 2660 Woodley Road, NW, Washington, DC 20008Website Link: http://bit.ly/1CbVvraPOC: Dameone Ferguson (NNSA)

  2. Pittsburgh Forum on Veteran Employment/Career Fair

    Broader source: Energy.gov [DOE]

    Location: Heinz Field, 100 Art Rooney Avenue, Pittsburgh, PAPOC:  Donna FriendWebsite: http://bit.ly/1q90WNk

  3. Careers & the disABLED Career Expo

    Broader source: Energy.gov [DOE]

    Location: Ronald Reagan Bldg, Washington, DCAttendees:  Terri Sosa (Science)POC:  Donna FriendWebsite: http://bit.ly/1tlHhNr

  4. InMon,

    Gasoline and Diesel Fuel Update (EIA)

    gas (common- tenance infrastructure. (Denver, also a Clean City, has also ly known as propane); coal-derived liquid fuels; fuels other than alcohol that are derived from...

  5. Risk of Hippocampal Metastases in Small Cell Lung Cancer Patients at Presentation and After Cranial Irradiation: A Safety Profile Study for Hippocampal Sparing During Prophylactic or Therapeutic Cranial Irradiation

    SciTech Connect (OSTI)

    Kundapur, Vijayananda; Ellchuk, Tasha; Ahmed, Shahid; Gondi, Vinai

    2015-03-15

    Purpose: Neurocognitive impairment (NI) in patients with small cell lung cancer (SCLC) after whole brain radiation treatment (WBRT) is a significant cause of morbidity. Hippocampal avoidance (HA) during WBRT may mitigate or prevent NI in such patients. However, this has not been tested in SCLC patients. The estimated risk of metastases in the HA region (HM) in patients with SCLC at diagnosis or after WBRT is unknown. Our study aimed to determine the risk of HM in patients with SCLC and to assess correlated clinical factors. Methods and Materials: Patients with SCLC who experienced brain metastases (BM) at presentation (de novo) or after WBRT treated at the Saskatoon Cancer Centre between 2005 and 2012 were studied. Relevant neuroimaging was independently reviewed by a neuroradiologist. HM was defined as metastases within 5 mm of the hippocampus. Logistic regression analysis was performed to assess correlation between various clinical variables and HM. Results: Seventy eligible patients were identified. Of 59 patients presenting with de novo BM, 3 patients (5%, 95% confidence interval [CI]: 0%-10.7%) had HM. Collectively there were 359 (range, 1-33) de novo BM with 3 (0.8%, 95% CI: 0%-1.7%) HM deposits. Twenty patients experienced progression of metastatic disease in the brain after WBRT. Of the 20 patients, only 1 patient (5%, 95% CI: 0%-14.5%) experienced HM. On logistic regression, no factors significantly correlated with HM. Conclusion: The overall incidence of HM before or after WBRT in SCLC patients is low, providing preliminary support for the safety of HA during planned clinical trials of HA-WBRT for SCLC.

  6. ON THE DETECTION OF IONIZING RADIATION ARISING FROM STAR-FORMING GALAXIES AT REDSHIFT z {approx} 3-4: LOOKING FOR ANALOGS OF 'STELLAR RE-IONIZERS'

    SciTech Connect (OSTI)

    Vanzella, Eros; Cristiani, Stefano; Nonino, Mario; Guo Yicheng; Giavalisco, Mauro; Grazian, Andrea; Castellano, Marco; Fontana, Adriano; Giallongo, Emanuele; Pentericci, Laura; Galametz, Audrey; Dickinson, Mark; Faber, S. M.; Newman, Jeffrey; Siana, Brian D.

    2012-05-20

    We use the spatially resolved, multi-band photometry in the GOODS South field acquired by the CANDELS project to constrain the nature of candidate Lyman continuum (LyC) emitters at redshift z {approx} 3.7 identified using ultradeep imaging below the Lyman limit (1{sigma} limit of Almost-Equal-To 30 AB in a 2'' diameter aperture). In 19 candidates out of a sample of 20 with flux detected at >3{sigma} level, the light centroid of the candidate LyC emission is offset from that of the Lyman break galaxy (LBG) by up to 1.''5. We fit the spectral energy distribution of the LyC candidates to spectral population synthesis models to measure photometric redshifts and the stellar population parameters. We also discuss the differences in the UV colors between the LBG and the LyC candidates, and how to estimate the escape fraction of ionizing radiation (f{sub esc}) in cases, like in most of our galaxies, where the LyC emission is spatially offset from the host galaxy. In all but one case we conclude that the candidate LyC emission is most likely due to lower redshift interlopers. Based on these findings, we argue that the majority of similar measurements reported in the literature need further investigation before it can be firmly concluded that LyC emission is detected. Our only surviving LyC candidate is an LBG at z = 3.795, which shows the bluest (B - V) color among LBGs at similar redshift, a stellar mass of M {approx} 2 Multiplication-Sign 10{sup 9} M{sub Sun }, weak interstellar absorption lines, and a flat UV spectral slope with no Ly{alpha} in emission. We estimate its f{sub esc} to be in the range 25%-100%, depending on the dust and intergalactic attenuation.

  7. Research Highlight

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

    H.E. Revercomb, H.M. Woolf, and H.B. Howell, 1998: "Meteorological applications of temperature and water vapor retrievals from the ground-based atmospheric emitted radiance...

  8. DOE International Energy Advisors | Department of Energy

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

    Stuttgart, Germany USNORTHCOM: U.S. Northern Command Peterson Air Force Base, CO USPACOM: U.S. Pacific Command Camp H.M. Smith, HI USSOUTHCOM: U.S. Southern Command Miami, FL

  9. Albany, OR * Anchorage, AK * Morgantown, WV * Pittsburgh, PA...

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

    modeling consistent with Biot's poroelastic theory was developed and imple- mented in FLAC and TOUGH2. * H-M models for fractured porous rocks were developed and implemented in a...

  10. NREL: Photovoltaics Research - Hao-Chih Yuan

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

    Yuan, "Multi-scale surface texture to improve blue response of nanoporous black silicon solar cells," to appear in Appl. Phys. Lett. J. Oh, T.G. Deutsch, H.-C. Yuan, and H.M....

  11. Harmonization of Federal and International Regulations

    Office of Environmental Management (EM)

    DOT/PHMSA Update Michael Conroy U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration Office of Hazardous Materials Safety Radioactive Materials - 2 - HM-230 (1/26/04) Harmonized with 2000 Version of IAEA's 1996 Edition - 3 - Changes to the IAEA Regulations Since 2000 2003 Amendment 2005 Edition 2009 Edition U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration Harmonization Rulemaking (HM-250) * Harmonize with 2009 Edition of

  12. Emerging Technologies Applicable to the Safe and Secure Transportation of Hazardous Materials

    Office of Environmental Management (EM)

    National Transportation Stakeholders Forum May 16, 2012 HMCRP Project HM-04: Emerging Technologies Applicable to Hazardous Materials Transportation Safety and Security 2 The HM-04 Team * Battelle - Prime - Bill Tate, Project Director/PI & Co-Author * Dr. Mark Abkowitz, Vanderbilt University - Co-Author * American Transportation Research Institute (ATRI) - Dan Murray, Lead * Visionary Solutions, LLC - Dan Hoglund, Lead * Olin Chemical Chlor-Alkali Division - Don Loftis 3 Project Objectives *

  13. Pulverized coal injection (PCI) at Inland`s No. 7 blast furnace

    SciTech Connect (OSTI)

    Carter, W.L.; Greenawald, P.B.; Ranade, M.G.; Ricketts, J.A.; Zuke, D.A.

    1995-12-01

    Fuel injection at the tuyeres has always been part of normal operating practice on this blast furnace. It has been used as much because of the beneficial effects on furnace operation as for the replacement of some of the coke that would otherwise be consumed. Fuel oil was used at first, but since the early 1980s it was more economical to inject natural gas. Studies in 1990 indicated that natural gas could be increased to 75 kg/tHM on No. 7 Furnace, and this would result in a coke rate of approximately 360 kg/tHM. It was apparent that coal injection offered significantly more opportunity for coke savings. Coke rate could be lowered to 300 kg/tHM with coal injected at 175 kg/tHM. Some combustion limitations were expected at that level. A coke rate of 270 kg/tHM with coal at 200 kg/tHM may be possible once these limitations are overcome. Furnace permeability was expected to limit the ability to reduce coke rate any further. In addition, the relative cost of coal would be significantly lower than the cost of coke it replaced. This lead to the decision late in 1991 to install pulverized coal injection (PCI) equipment for all of Inland`s blast furnaces. This paper will deal with PCI experience at No. 7 Blast Furnace.

  14. Oil and gas developments in North Africa in 1985

    SciTech Connect (OSTI)

    Michel, R.C.

    1986-10-01

    Petroleum rights in the 6 North African countries (Algeria, Egypt, Libya, Morocco, Sudan, and Tunisia) covered in this paper were 1,839,817 km/sup 2/ at the end of 1985, a decrease of 3% from the 1,896,446 km/sup 2/ held at the end of 1984. This decrease mainly is due to significant relinquishments made in Algeria, Egypt, and Tunisia. Morocco, however, had an increase of 18,087 km/sup 2/. Oil discoveries were reported in Algeria (possibly 5), Libya (at least 2), and Egypt (16). Only 1 gas find was made (in Morocco). According to sparse information, development drilling may have decreased markedly during 1985. Oil and condensate production increased by 3.1% to approximately 3,054,000 b/d compared to about 2,963,400 b/d in 1984. No statistics are currently available on gas production in North Africa. 8 figures, 27 tables.

  15. 2011 SPR Report to Congress | Department of Energy

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

    SPR Report to Congress 2011 SPR Report to Congress Highlights from the report include: Drawdown 2011 - Libya Collective Action On June 23, 2011, President Obama authorized the sale and drawdown of 30 million barrels of crude oil from the Strategic Petroleum Reserve as the United States' share of a coordinated 60 million barrel release of oil from member countries of the IEA that had been announced the same day. The Strategic Petroleum Reserve conducted an online competitive sale that resulted in

  16. East Coast (PADD 1) Imports from All Countries

    Gasoline and Diesel Fuel Update (EIA)

    Import Area: East Coast (PADD 1) Midwest (PADD 2) Gulf Coast (PADD 3) Rocky Mountain (PADD 4) West Coast (PADD 5) Period/Unit: Monthly-Thousand Barrels Monthly-Thousand Barrels per Day Annual-Thousand Barrels Annual-Thousand Barrels per Day Country: All Countries Persian Gulf OPEC Algeria Angola Ecuador Iraq Kuwait Libya Nigeria Qatar Saudi Arabia United Arab Emirates Venezuela Non OPEC Albania Argentina Aruba Australia Austria Azerbaijan Bahamas Bahrain Barbados Belarus Belgium Bosnia and

  17. Technically Recoverable Shale Oil and Shale Gas Resources:

    Gasoline and Diesel Fuel Update (EIA)

    Libya Independent Statistics & Analysis www.eia.gov U.S. Department of Energy Washington, DC 20585 September 2015 September 2015 U.S. Energy Information Administration | Technically Recoverable Shale Oil and Shale Gas Resources i This report was prepared by the U.S. Energy Information Administration (EIA), the statistical and analytical agency within the U.S. Department of Energy. By law, EIA's data, analyses, and forecasts are independent of approval by any other officer or employee of the

  18. Presentation title: This can be up to 2 lines

    Gasoline and Diesel Fuel Update (EIA)

    April 12, 2011 2011 Summer Transportation Fuels Outlook Key factors driving the short-term outlook 2 2011 Summer Transportation Fuels Outlook * Disruption of crude oil and liquefied natural gas supply from Libya and uncertainty over security of supply from other countries in the Middle East and North Africa region * Strong growth in world consumption, driven by growth in emerging economies * Slow growth in non-OPEC production * Reliance on drawdown of inventories and increasing oil production

  19. Short-Term Energy Outlook - U.S. Energy Information Administration (EIA)

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

    3b : Non-OPEC Petroleum and Other Liquids Supply (Million Barrels per Day) Either scripts and active content are not permitted to run or Adobe Flash Player version ${version_major}.${version_minor}.${version_revision} or greater is not installed. Get Adobe Flash Player - = no data available OPEC = Organization of Petroleum Exporting Countries: Algeria, Angola, Ecuador, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, the United Arab Emirates, Venezuela. Notes: The approximate

  20. Total Crude Oil and Products Imports from All Countries

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

    Country: All Countries Persian Gulf OPEC Algeria Angola Ecuador Iraq Kuwait Libya Nigeria Qatar Saudi Arabia United Arab Emirates Venezuela Non OPEC Albania Argentina Aruba Australia Austria Azerbaijan Bahamas Bahrain Barbados Belarus Belgium Belize Benin Bolivia Bosnia and Herzegovina Brazil Brunei Bulgaria Burma Cameroon Canada Chad Chile China Colombia Congo (Brazzaville) Congo (Kinshasa) Cook Islands Costa Rica Croatia Cyprus Czech Republic Denmark Dominican Republic Egypt El Salvador

  1. Total Net Imports of Crude Oil and Petroleum Products into the U.S.

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

    Country: Total All Countries Persian Gulf OPEC Algeria Angola Ecuador Iran Iraq Kuwait Libya Nigeria Qatar Saudi Arabia United Arab Emirates Venezuela Non OPEC Afghanistan Albania Andora Anguilla Antigua and Barbuda Argentina Armenia Aruba Australia Austria Azerbaijan Bahamas Bahrain Bangladesh Barbados Belarus Belgium Belize Benin Bermuda Bolivia Bosnia and Herzegovina Botswana Brazil Brunei Bulgaria Burkina Faso Burma Cambodia Cameroon Canada Cayman Islands Chad Chile China Cocos (Keeling)

  2. U.S. Imports from All Countries

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

    Import Area: U.S. Period/Unit: Monthly-Thousand Barrels Monthly-Thousand Barrels per Day Annual-Thousand Barrels Annual-Thousand Barrels per Day Country: All Countries Persian Gulf OPEC Algeria Angola Ecuador Iraq Kuwait Libya Nigeria Qatar Saudi Arabia United Arab Emirates Venezuela Non OPEC Albania Argentina Aruba Australia Austria Azerbaijan Bahamas Bahrain Barbados Belarus Belgium Belize Benin Bolivia Bosnia and Herzegovina Brazil Brunei Bulgaria Burma Cameroon Canada Chad Chile China

  3. Request for Proposal No. DE-SOL-0008418 Section J, Appendix D

    National Nuclear Security Administration (NNSA)

    D SECTION J APPENDIX D SENSITIVE FOREIGN NATIONS CONTROL 1. Pursuant to the Contract Section I Clause 952.204-71 entitled "Sensitive Foreign Nations Controls," "sensitive foreign nations" is one of the countries listed below: Algeria Armenia Azerbaijan Belarus China (People's Republic of China) Cuba Georgia Hong Kong India Iran Iraq Israel Kazakhstan Kyrgyzstan Libya Moldova North Korea (Democratic People's Republic of) Pakistan Russia Sudan Syria Taiwan Tajikistan

  4. Microsoft Word - SEC J_Appendix D - Sensitive Foreign Nations Control

    National Nuclear Security Administration (NNSA)

    D, Page 1 SECTION J APPENDIX D SENSITIVE FOREIGN NATIONS CONTROL 1. Pursuant to the Contract Section I Clause entitled "Sensitive Foreign Nations Controls," "sensitive foreign nations" is one of the countries listed below: Algeria Armenia Azerbaijan Belarus China (People's Republic of China) Cuba Georgia Hong Kong India Iran Iraq Israel Kazakhstan Kyrgyzstan Libya Moldova North Korea (Democratic People's Republic of) Pakistan Russia Sudan Syria Taiwan Tajikistan Turkmenistan

  5. Central Washington University: 2014 Engineering Technologies, Safety & Construction Fair

    Broader source: Energy.gov [DOE]

    Location: 400 E. University Way Ellensburg, WA 98926, SURC BallroomPOC: Heather BainWebsite: http://bit.ly/1pgOpN7

  6. HBCU College Festival sponsored by Alfred Street Baptist Church

    Broader source: Energy.gov [DOE]

    Location: T.C. Williams High School, 3330 King St, Alexandria, VA 22302Attendees: Rauland Sharp (HC) and Dameone Ferguson (NNSA)POC: Chester Scott Website: http://bit.ly/1BARRqp

  7. Gallaudet University Spring 2015 Career Fair

    Broader source: Energy.gov [DOE]

    Gallaudet University, Field House Gymnasium, 800 Florida Avenue NE, Washington, DC 20002Contact:DOECorporateRecruitment@hq.doe.govhttp://bit.ly/1vjfWjFThis event was rescheduled due to inclement...

  8. 03-10-05.cdr

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

    as of 030905: 4,337 standard waste boxes 1,356 ten-drum overpacks 60,833 waste drums 27,031 cubic meters Operations: First on, last out A "TRU-ly" unique waste story ......

  9. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    ... We present an analysis of the star formation rates (SFRs) of these galaxies as a function ... the H and Ly luminosity functions in a 100, 000 Mpcsup 3more volume of space. ...

  10. IES TM-30-15: Learn the Basics, See the Results

    Energy Savers [EERE]

    IES Method for Evaluating Light Source Color Rendition http:bit.ly1IWZxVu Optics Express journal article that provides overview of the IES method: Development of the...

  11. Social Media | Argonne National Laboratory

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

    Timeline Photos from Facebook More Twitter @argonne 4 hours ago Missed "What is the Brain Initiative?" Fear not, science-y goodness awaits you here @C2ST - http:bit.ly...

  12. Naval Support Activity (NSA) in Bethesda Employment Education Fair

    Broader source: Energy.gov [DOE]

    Location: NSA Bethesda Fitness Center (Gymnasium, Bldg 17), 8901 Wisconsin Ave., Bethesda, MD 20889Attendees: Donna Friend (HC) and Rauland Sharp (HC)POC: Donna FriendWebsite: http://bit.ly/1yTjTNu

  13. 2013 Progress Report -- DOE Joint Genome Institute None 59 BASIC...

    Office of Scientific and Technical Information (OSTI)

    bit.lyJGI-Vision for the Institute. A central focus of this Strategic Vision is to bridge the gap between sequenced genomes and an understanding of biological functions at the...

  14. TITLE AUTHORS SUBJECT SUBJECT RELATED DESCRIPTION PUBLISHER AVAILABILI...

    Office of Scientific and Technical Information (OSTI)

    bit ly JGI Vision for the Institute A central focus of this Strategic Vision is to bridge the gap between sequenced genomes and an understanding of biological functions at the...

  15. "Title","Creator/Author","Publication Date","OSTI Identifier...

    Office of Scientific and Technical Information (OSTI)

    bit.lyJGI-Vision for the Institute. A central focus of this Strategic Vision is to bridge the gap between sequenced genomes and an understanding of biological functions at the...

  16. Veterans Employment Forum

    Broader source: Energy.gov [DOE]

    Location: 614 SW 11th Avenue, Portland, OR 97205, 2nd Floor Library RoomPOC: Heather BainWebsite: http://bit.ly/1t6XjaO

  17. NARROWBAND IMAGING OF ESCAPING LYMAN-CONTINUUM EMISSION IN THE SSA22 FIELD

    SciTech Connect (OSTI)

    Nestor, Daniel B.; Shapley, Alice E.; Steidel, Charles C.; Siana, Brian

    2011-07-20

    We present the results of an ultradeep, narrowband imaging survey for Lyman-continuum (LyC) emission at z {approx} 3 in the SSA22a field. We employ a custom narrowband filter centered at {lambda} = 3640 A (NB3640), which probes the LyC region for galaxies at z {>=} 3.06. We also analyze new and archival NB4980 imaging tuned to the wavelength of the Ly{alpha} emission line at z = 3.09, and archival broadband B, V, and R images of the non-ionizing UV continuum. Our NB3640 images contain 26 z {>=} 3.06 Lyman break galaxies (LBGs) as well as a set of 130 Ly{alpha} emitters (LAEs), identified by their excess NB4980 flux relative to the BV continuum. Six LBGs and 28 LAEs are detected in the NB3640 image. LBGs appear to span a range of NB3640-R colors, while LAEs appear bimodal in their NB3640-R properties. We estimate average UV-to-LyC flux density ratios, corrected for foreground contamination and intergalactic medium absorption, finding (F{sub UV}/F{sub LyC}){sup LBG}{sub corr} = 11.3{sup +10.3}{sub -5.4}, which implies an LBG LyC escape fraction f{sup LyC}{sub esc} {approx} 0.1, and (F{sub UV}/F{sub LyC}){sup LAE}{sub corr} = 2.2{sup +0.9}{sub -0.6}. The strikingly blue LAE flux density ratios defy interpretation in terms of standard stellar population models. Assuming (F{sub UV}/F{sub LyC}){sup LBG}{sub corr} applies down to L = 0.1L*, we estimate a galaxy contribution to the intergalactic hydrogen ionization rate that is consistent with independent estimates based on the Ly{alpha} forest opacity at z {approx_equal} 3. If we assume that (F{sub UV}/F{sub LyC}){sup LAE}{sub corr} holds at the faintest luminosities, the galaxy contribution significantly exceeds that inferred from the Ly{alpha} forest. We interpret our results in terms of a model where LyC photons escape over only {approx}10%-20% of solid angle. When advantageously oriented, a galaxy will exhibit a low UV-to-LyC ratio, an effect enhanced for more compact galaxies. This model, however, does not adequately explain the extremely blue NB3640-R colors measured for some LAEs in our sample. Further follow-up study of these faint LAEs is crucial, given the potentially important contribution similar objects make to the process of reionization.

  18. Structure of 5-hydroxymethylcytosine-specific restriction enzyme, AbaSI, in complex with DNA

    SciTech Connect (OSTI)

    Horton, John R.; Borgaro, Janine G.; Griggs, Rose M.; Quimby, Aine; Guan, Shengxi; Zhang, Xing; Wilson, Geoffrey G.; Zheng, Yu; Zhu, Zhenyu; Cheng, Xiaodong

    2014-07-03

    AbaSI, a member of the PvuRts1I-family of modification-dependent restriction endonucleases, cleaves DNA containing 5-hydroxymethylctosine (5hmC) and glucosylated 5hmC (g5hmC), but not DNA containing unmodified cytosine. AbaSI has been used as a tool for mapping the genomic locations of 5hmC, an important epigenetic modification in the DNA of higher organisms. Here we report the crystal structures of AbaSI in the presence and absence of DNA. These structures provide considerable, although incomplete, insight into how this enzyme acts. AbaSI appears to be mainly a homodimer in solution, but interacts with DNA in our structures as a homotetramer. Each AbaSI subunit comprises an N-terminal, Vsr-like, cleavage domain containing a single catalytic site, and a C-terminal, SRA-like, 5hmC-binding domain. Two N-terminal helices mediate most of the homodimer interface. Dimerization brings together the two catalytic sites required for double-strand cleavage, and separates the 5hmC binding-domains by ~ 70 , consistent with the known activity of AbaSI which cleaves DNA optimally between symmetrically modified cytosines ~ 22 bp apart. The eukaryotic SET and RING-associated (SRA) domains bind to DNA containing 5-methylcytosine (5mC) in the hemi-methylated CpG sequence. They make contacts in both the major and minor DNA grooves, and flip the modified cytosine out of the helix into a conserved binding pocket. In contrast, the SRA-like domain of AbaSI, which has no sequence specificity, contacts only the minor DNA groove, and in our current structures the 5hmC remains intra-helical. A conserved, binding pocket is nevertheless present in this domain, suitable for accommodating 5hmC and g5hmC. We consider it likely, therefore, that base-flipping is part of the recognition and cleavage mechanism of AbaSI, but that our structures represent an earlier, pre-flipped stage, prior to actual recognition.

  19. Final Technical Report

    SciTech Connect (OSTI)

    Stoessel, Chris

    2013-11-13

    This project developed a new high-performance R-10/high SHGC window design, reviewed market positioning and evaluated manufacturing solutions required for broad market adoption. The project objectives were accomplished by: identifying viable technical solutions based on modeling of modern and potential coating stacks and IGU designs; development of new coating material sets for HM thin film stacks, as well as improved HM IGU designs to accept multiple layers of HM films; matching promising new coating designs with new HM IGU designs to demonstrate performance gains; and, in cooperation with a window manufacturer, assess the potential for high-volume manufacturing and cost efficiency of a HM-based R-10 window with improved solar heat gain characteristics. A broad view of available materials and design options was applied to achieve the desired improvements. Gated engineering methodologies were employed to guide the development process from concept generation to a window demonstration. The project determined that a slightly de-rated window performance allows formulation of a path to achieve the desired cost reductions to support end consumer adoption.

  20. Two plateaux for palladium hydride and the effect of helium from tritium decay on the desorption plateau pressure for palladium tritide

    SciTech Connect (OSTI)

    Walters, R.T.; Lee, M.W. )

    1991-10-01

    Two plateaux are observed in the desorption isotherm for palladium hydride: a lower plateau pressure for a hydrogen/metal atom ratio (H/M) less than about 0.3 and a slightly higher plateau pressure for H/M greater than about 0.3. This higher pressure corresponds to the reported pressure for palladium hydride. These observations were made for a large surface area palladium powder exposed to both protium and tritium. Helium buildup form tritium decay decreases the lower plateau pressure but does not affect the observations for H/M greater than about 0.3. In this paper, a multiple-energy hydrogen site occupancy model is proposed to explain qualitatively both the dual plateau and the helium effect in palladium hydride.

  1. A REFINED ESTIMATE OF THE IONIZING EMISSIVITY FROM GALAXIES AT z {approx_equal} 3: SPECTROSCOPIC FOLLOW-UP IN THE SSA22a FIELD

    SciTech Connect (OSTI)

    Nestor, Daniel B.; Shapley, Alice E.; Kornei, Katherine A.; Steidel, Charles C.; Siana, Brian

    2013-03-01

    We investigate the contribution of star-forming galaxies to the ionizing background at z {approx} 3, building on previous work based on narrowband (NB3640) imaging in the SSA22a field. We use new Keck/LRIS spectra of Lyman break galaxies (LBGs) and narrowband-selected Ly{alpha} emitters (LAEs) to measure redshifts for 16 LBGs and 87 LAEs at z > 3.055, such that our NB3640 imaging probes the Lyman-continuum (LyC) region. When we include the existing set of spectroscopically confirmed LBGs, our total sample with z > 3.055 consists of 41 LBGs and 91 LAEs, of which 9 LBGs and 20 LAEs are detected in our NB3640 image. With our combined imaging and spectroscopic data sets, we critically investigate the origin of NB3640 emission for detected LBGs and LAEs. We remove from our samples three LBGs and three LAEs with spectroscopic evidence of contamination of their NB3640 flux by foreground galaxies and statistically model the effects of additional, unidentified foreground contaminants. The resulting contamination and LyC-detection rates, respectively, are 62% {+-} 13% and 8% {+-} 3% for our LBG sample, and 47% {+-} 10% and 12% {+-} 2% for our LAE sample. The corresponding ratios of non-ionizing UV to LyC flux density, corrected for intergalactic medium (IGM) attenuation, are 18.0{sup +34.8} {sub -7.4} for LBGs and 3.7{sup +2.5} {sub -1.1} for LAEs. We use these ratios to estimate the total contribution of star-forming galaxies to the ionizing background and the hydrogen photoionization rate in the IGM, finding values larger than, but consistent with, those measured in the Ly{alpha} forest. Finally, the measured UV to LyC flux-density ratios imply model-dependent LyC escape fractions of f {sup LyC} {sub esc} {approx} 5%-7% for our LBG sample and f {sup LyC} {sub esc} {approx} 10%-30% for our fainter LAE sample.

  2. Structure of Naegleria Tet-like dioxygenase (NgTet1) in complexes with a reaction intermediate 5-hydroxymethylcytosine DNA

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

    Hashimoto, Hideharu; Pais, June E.; Dai, Nan; Corrêa, Jr., Ivan R.; Zhang, Xing; Zheng, Yu; Cheng, Xiaodong

    2015-08-31

    The family of ten-eleven translocation (Tet) dioxygenases is widely distributed across the eukaryotic tree of life, from mammals to the amoeboflagellate Naegleria gruberi. Like mammalian Tet proteins, the Naegleria Tet-like protein, NgTet1, acts on 5-methylcytosine (5mC) and generates 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC) and 5-carboxylcytosine (5caC) in three consecutive, Fe(II)- and α-ketoglutarate-dependent oxidation reactions. The two intermediates, 5hmC and 5fC, could be considered either as the reaction product of the previous enzymatic cycle or the substrate for the next cycle. Here we present a new crystal structure of NgTet1 in complex with DNA containing a 5hmC. Along with the previously solvedmore » NgTet1–5mC structure, the two complexes offer a detailed picture of the active site at individual stages of the reaction cycle. In the crystal, the hydroxymethyl (OH-CH2-) moiety of 5hmC points to the metal center, representing the reaction product of 5mC hydroxylation. The hydroxyl oxygen atom could be rotated away from the metal center, to a hydrophobic pocket formed by Ala212, Val293 and Phe295. Such rotation turns the hydroxyl oxygen atom away from the product conformation, and exposes the target CH2 towards the metal-ligand water molecule, where a dioxygen O2 molecule would occupy to initiate the next round of reaction by abstracting a hydrogen atom from the substrate. The Ala212-to-Val (A212V) mutant profoundly limits the product to 5hmC, probably due to the reduced hydrophobic pocket size restricts the binding of 5hmC as a substrate.« less

  3. Structure of Naegleria Tet-like dioxygenase (NgTet1) in complexes with a reaction intermediate 5-hydroxymethylcytosine DNA

    SciTech Connect (OSTI)

    Hashimoto, Hideharu; Pais, June E.; Dai, Nan; Corra, Jr., Ivan R.; Zhang, Xing; Zheng, Yu; Cheng, Xiaodong

    2015-08-31

    The family of ten-eleven translocation (Tet) dioxygenases is widely distributed across the eukaryotic tree of life, from mammals to the amoeboflagellate Naegleria gruberi. Like mammalian Tet proteins, the Naegleria Tet-like protein, NgTet1, acts on 5-methylcytosine (5mC) and generates 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC) and 5-carboxylcytosine (5caC) in three consecutive, Fe(II)- and ?-ketoglutarate-dependent oxidation reactions. The two intermediates, 5hmC and 5fC, could be considered either as the reaction product of the previous enzymatic cycle or the substrate for the next cycle. Here we present a new crystal structure of NgTet1 in complex with DNA containing a 5hmC. Along with the previously solved NgTet15mC structure, the two complexes offer a detailed picture of the active site at individual stages of the reaction cycle. In the crystal, the hydroxymethyl (OH-CH2-) moiety of 5hmC points to the metal center, representing the reaction product of 5mC hydroxylation. The hydroxyl oxygen atom could be rotated away from the metal center, to a hydrophobic pocket formed by Ala212, Val293 and Phe295. Such rotation turns the hydroxyl oxygen atom away from the product conformation, and exposes the target CH2 towards the metal-ligand water molecule, where a dioxygen O2 molecule would occupy to initiate the next round of reaction by abstracting a hydrogen atom from the substrate. The Ala212-to-Val (A212V) mutant profoundly limits the product to 5hmC, probably due to the reduced hydrophobic pocket size restricts the binding of 5hmC as a substrate.

  4. Influence of Lymphatic Invasion on Locoregional Recurrence Following Mastectomy: Indication for Postmastectomy Radiotherapy for Breast Cancer Patients With One to Three Positive Nodes

    SciTech Connect (OSTI)

    Matsunuma, Ryoichi; Oguchi, Masahiko; Fujikane, Tomoko; Matsuura, Masaaki; Sakai, Takehiko; Kimura, Kiyomi; Morizono, Hidetomo; Iijima, Kotaro; Izumori, Ayumi; Miyagi, Yumi; Nishimura, Seiichiro; Makita, Masujiro; Gomi, Naoya; Horii, Rie; Akiyama, Futoshi; Iwase, Takuji

    2012-07-01

    Purpose: The indication for postmastectomy radiotherapy (PMRT) in breast cancer patients with one to three positive lymph nodes has been in discussion. The purpose of this study was to identify patient groups for whom PMRT may be indicated, focusing on varied locoregional recurrence rates depending on lymphatic invasion (ly) status. Methods and Materials: Retrospective analysis of 1,994 node-positive patients who had undergone mastectomy without postoperative radiotherapy between January 1990 and December 2000 at our hospital was performed. Patient groups for whom PMRT should be indicated were assessed using statistical tests based on the relationship between locoregional recurrence rate and ly status. Results: Multivariate analysis showed that the ly status affected the locoregional recurrence rate to as great a degree as the number of positive lymph nodes (p < 0.001). Especially for patients with one to three positive nodes, extensive ly was a more significant factor than stage T3 in the TNM staging system for locoregional recurrence (p < 0.001 vs. p = 0.295). Conclusion: Among postmastectomy patients with one to three positive lymph nodes, patients with extensive ly seem to require local therapy regimens similar to those used for patients with four or more positive nodes and also seem to require consideration of the use of PMRT.

  5. The mystery of spectral breaks: Lyman continuum absorption by photon-photon pair production in the Fermi GeV spectra of bright blazars

    SciTech Connect (OSTI)

    Stern, Boris E. [Institute for Nuclear Research, Russian Academy of Sciences, Prospekt 60-letiya Oktyabrya 7a, Moscow 117312 (Russian Federation); Poutanen, Juri, E-mail: stern.boris@gmail.com, E-mail: juri.poutanen@utu.fi [Tuorla Observatory, University of Turku, Vislntie 20, FI-21500 Piikki (Finland)

    2014-10-10

    We re-analyze Fermi/LAT ?-ray spectra of bright blazars using the new Pass 7 version of the detector response files and detect breaks at ?5 GeV in the rest-frame spectra of 3C 454.3 and possibly also 4C +21.35, associated with the photon-photon pair production absorption by the He II Lyman continuum (LyC). We also detect significant breaks at ?20 GeV associated with hydrogen LyC in both the individual spectra and the stacked redshift-corrected spectrum of several bright blazars. The detected breaks in the stacked spectra univocally prove that they are associated with atomic ultraviolet emission features of the quasar broad-line region (BLR). The dominance of the absorption by the hydrogen Ly complex over He II, a small detected optical depth, and break energy consistent with head-on collisions with LyC photons imply that the ?-ray emission site is located within the BLR, but most of the BLR emission comes from a flat disk-like structure producing little opacity. Alternatively, the LyC emission region size might be larger than the BLR size measured from reverberation mapping, and/or the ?-ray emitting region is extended. These solutions would resolve the long-standing issue of how the multi-hundred GeV photons can escape from the emission zone without being absorbed by softer photons.

  6. untitled

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

    Ac cc co om mp plliis sh hm me en nt ts s A Ac cc co om mp plliis sh hm me en nt ts s 2 20 00 06 6 2 20 00 06 6 F Fe eb br ru ua ar ry y * * 2 20 00 06 6 THE LITTLE ROBOT THAT COULD . . . Meet the Sandia robot that helped secure a radiation source at White Sands Missile Range. Details on page 5. L La ab bs s L La ab bs s Sandia National Laboratories W elcome to this year's edition of the annual Lab News Labs Accomplishments. Throughout this 16-page document, you'll find a resounding affirmation

  7. Oil and gas developments in North Africa in 1984

    SciTech Connect (OSTI)

    Michel, R.Ch.

    1985-10-01

    Petroleum rights in the 6 North African countries (Algeria, Egypt, Libya, Morocco, Sudan, and Tunisia) covered in this paper were 1,906,065 km/sup 2/ at the end of 1984, an increase of 4.6% from the 1,821,966 km/sup 2/ in force at the end of 1983. This increase is due to large awards in the Sudan despite significant relinquishments elsewhere. Seismic surveys conducted during 1984 decreased to about 510.5 crew-months onshore and 29.5 crew-months offshore. However, exploration in and off Egypt was higher compared to 1983. Exploratory drilling was lower, with only 125 wells drilled compared to 179 tests completed in 1983. The main decrease was in Egypt and Sudan, but drilling in Libya resulted in 20 more completions. A significant oil discovery was made in the offshore part of the Sirte basin, off southwest Cyrenaica. The success rate in North Africa ranged from 19% to 50% (Libya). Development drilling increased during 1984, as higher activity appears to have taken place in 3 countries. Oil production, with an estimated daily rate of 2,952,570 bbl, was up 2.8% from 1983 (2,871,460 BOPD). In Egypt, 7 fields located in the Gulf of Suez area went on stream during the year. Political unrest, which prevailed in southern Sudan during most of 1984, will likely delay the start-up of production in several fields. No statistics are available on gas production in North African countries.

  8. Oil and gas developments in North Africa in 1984

    SciTech Connect (OSTI)

    Michel, R.C.

    1985-10-01

    Petroleum rights in the 6 North African countries (Algeria, Egypt, Libya, Morocco, Sudan, and Tunisia) covered in this paper were 1,906,065 km/sup 2/ at the end of 1984. An increase of 4.6% from the 1,821,966 km/sup 2/ in force at the end of 1983. This increase is due to large awards in the Sudan despite significant relinquishments elsewhere. Seismic surveys conducted during 1984 decreased to about 510.5 crew-months onshore and 29.5 crew-months offshore. However, exploration in and off Egypt was higher compared to 1983. Exploratory drilling was lower, with only 125 wells drilled compared to 179 tests completed in 1983. The main decrease was in Egypt and Sudan, but drilling in Libya resulted in 20 more completions. A significant oil discovery was made in the offshore part of the Sirte basin, off southwest Cyrenaica. The success rate in North America ranged from 19% to 50% (Libya). Development drilling increased during 1984, as higher activity appears to have taken place in 3 countries. Oil production, with an estimated daily rate of 2,952,570 bbl, was 2.8% from 1983 (2,871,460 BOPD). In Egypt, 7 fields located in the Gulf of Suez area went on stream during the year. Political unrest, which prevailed in southern Sudan during most of 1984, will likely delay the start-up of production in several fields. No statistics are available on gas production in North African countries. 9 figures, 27 tables.

  9. Africa: Unrest and restrictive terms limit abundant potential. [Oil and gas exploration and development in Africa

    SciTech Connect (OSTI)

    Not Available

    1993-08-01

    This paper summarizes the drilling and exploration activity of the oil and gas industries of Egypt, Libya, Tunisia, Algeria, Morocco, Nigeria, Cameroon, Gabon, the Congo, Angola, and South Africa. Information is provided on current and predicted trends in well drilling activities (both onshore and offshore), numbers of new wells, footage information, production statistics and what fields accounted for this production, and planned new exploration activities. The paper also describes the current status of government policies and political problems affecting the oil and gas industry.

  10. Turmoil doesn`t dampen enthusiasm

    SciTech Connect (OSTI)

    1997-08-01

    The paper discusses the outlook for the African gas and oil industries. Though Africa remains politically and economically volatile, its vast energy potential is becoming increasingly attractive to foreign oil and gas companies. Separate evaluations are given for Algeria, Egypt, Nigeria, Angola, Libya, Congo, Gabon, Tunisia, Cameroon, Cote D`Ivoire, and briefly for South Africa, Sudan, Equatorial Guinea, Ghana, Zaire, Benin, Mozambique, Chad, Namibia, Tanzania, Eritrea, Guinea-Bissau, Senegal, Morocco, Sao Tome and Principe, Ethiopia, Niger, Madagascar, Rwanda, Mauritania, Seychelles, Uganda, and Liberia.

  11. Short-Term Energy Outlook September 2013

    Gasoline and Diesel Fuel Update (EIA)

    (STEO) Highlights  Monthly average crude oil prices increased for the fourth consecutive month in August 2013, as supply disruptions in Libya increased and concerns over the conflict in Syria intensified. The U.S. Energy Information Administration's (EIA) forecast for Brent crude oil spot price, which averaged $108 per barrel during the first half of 2013, averages $109 per barrel over the second half of 2013 and $102 per barrel in 2014, $5 per barrel and $2 per barrel higher than forecast in

  12. Short-Term Energy Outlook Supplement: Status of Libyan Loading Ports and Oil and Natural Gas Fields

    Gasoline and Diesel Fuel Update (EIA)

    Short-Term Energy Outlook Supplement: Status of Libyan Loading Ports and Oil and Natural Gas Fields Tuesday, September 10, 2013, 10:00AM EST Overview During July and August 2013, protests at major oil loading ports in the central-eastern region of Libya forced the complete or partial shut-in of oil fields linked to the ports. As a result of protests at ports and at some oil fields, crude oil production fell to 1.0 million barrels per day (bbl/d) in July and 600,000 bbl/d in August, although the

  13. Word Pro - S3

    Gasoline and Diesel Fuel Update (EIA)

    6 U.S. Energy Information Administration / Monthly Energy Review February 2016 Table 3.3c Petroleum Trade: Imports From OPEC Countries (Thousand Barrels per Day) Algeria a Angola b Ecuador c Iraq Kuwait d Libya e Nigeria f Saudi Arabia d Vene- zuela Other g Total OPEC 1960 Average ...................... a ( ) b ( ) c ( ) 22 182 e ( ) f ( ) 84 911 34 1,233 1965 Average ...................... a ( ) b ( ) c ( ) 16 74 42 f ( ) 158 994 155 1,439 1970 Average ...................... 8 b ( ) c ( ) - 48

  14. Non-OPEC oil supply continues to grow

    SciTech Connect (OSTI)

    Knapp, D.H.

    1995-12-25

    Global reserves of crude oil remain at 1 trillion bbl, according to OGJ`s annual survey of producing countries. Significant gains are in Brazil, Colombia, Congo, Egypt, Libya, Nigeria, Oman, and Papua New Guinea. Decreases were reported by Indonesia, Norway, the U.K., Iran, Canada, Mexico, and the US. Natural gas reserves slipped to 4.9 quadrillion cu ft. The major production trend is a lasting surge from outside of OPEC. This year`s Worldwide Production report begins with a detailed analysis of this crucial development by an international authority. This article discusses the OECD outlook by region and the turnaround in production in the former Soviet Union.

  15. Revised Manuscript

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

    Energy Levels of Light Nuclei A 7 D.R. Tilley a,b , C.M. Cheves a,c , J.L. Godwin a,c , G.M. Hale d , H.M. Hofmann e , J.H. Kelley a,b , C.G. Sheu a,c and H.R. Weller a,c a ...

  16. Revised Manuscript

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

    Energy Levels of Light Nuclei A 6 D.R. Tilley a,b , C.M. Cheves a,c , J.L. Godwin a,c , G.M. Hale d , H.M. Hofmann e , J.H. Kelley a,b , C.G. Sheu a,c and H.R. Weller a,c a ...

  17. Bench-Scale Cross Flow Filtration of

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

    1 W.F. Feltz D.D. Turner H.B. Howell W.L. Smith R.O. Knuteson H.M. Woolf J. Comstock C. ... One of the first examples demonstrating this procedure was given by Smith (1970). ...

  18. African oil plays

    SciTech Connect (OSTI)

    Clifford, A.J. )

    1989-09-01

    The vast continent of Africa hosts over eight sedimentary basins, covering approximately half its total area. Of these basins, only 82% have entered a mature exploration phase, 9% have had little or no exploration at all. Since oil was first discovered in Africa during the mid-1950s, old play concepts continue to bear fruit, for example in Egypt and Nigeria, while new play concepts promise to become more important, such as in Algeria, Angola, Chad, Egypt, Gabon, and Sudan. The most exciting developments of recent years in African oil exploration are: (1) the Gamba/Dentale play, onshore Gabon; (2) the Pinda play, offshore Angola; (3) the Lucula/Toca play, offshore Cabinda; (4) the Metlaoui play, offshore Libya/Tunisia; (5) the mid-Cretaceous sand play, Chad/Sudan; and (6) the TAG-I/F6 play, onshore Algeria. Examples of these plays are illustrated along with some of the more traditional oil plays. Where are the future oil plays likely to develop No doubt, the Saharan basins of Algeria and Libya will feature strongly, also the presalt of Equatorial West Africa, the Central African Rift System and, more speculatively, offshore Ethiopia and Namibia, and onshore Madagascar, Mozambique, and Tanzania.

  19. "Ask Argonne" - Charlie Catlett, Computer Scientist, Part 2

    ScienceCinema (OSTI)

    Catlett, Charlie

    2014-07-15

    A few weeks back, computer scientist Charlie Catlett talked a bit about the work he does and invited questions from the public during Part 1 of his "Ask Argonne" video set (http://bit.ly/1joBtzk). In Part 2, he answers some of the questions that were submitted. Enjoy!

  20. Slide 1

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

    nif ica ntl y Re du ce s Lo ng -Te rm Mo rtg ag e Co sts At Co mp let ion , Sh ifts ... ifi ca nt ly Re du ce s Lo ng -T er m Mo rtg ag e Co st s At Co m pl et io n, Sh ift ...

  1. "Ask Argonne" - Robert Jacob, Climate Scientist, Part 2

    ScienceCinema (OSTI)

    Jacob, Robert

    2014-11-24

    Previously, climate scientist Robert Jacob talked a bit about the work he does and invited questions from the public during Part 1 of his "Ask Argonne" video set (http://bit.ly/1aK6WDv). In Part 2, he answers some of the questions that were submitted.

  2. THE PHOTON UNDERPRODUCTION CRISIS

    SciTech Connect (OSTI)

    Kollmeier, Juna A. [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Weinberg, David H.; McEwen, Joseph [Astronomy Department and CCAPP, Ohio State University, Columbus, OH 43210 (United States); Oppenheimer, Benjamin D.; Danforth, Charles [Astronomy Department, University of Colorado, Boulder, CO 80309 (United States); Haardt, Francesco [Dipartimento di Scienza e Alta Tecnologia, Universit dell'Insubria, Via Valleggio 11, I-22100 Como (Italy); Katz, Neal; Fardal, Mark [Astronomy Department, University of Massachusetts, Amherst, MA 01003 (United States); Dav, Romeel [University of the Western Cape, Bellville, Cape Town 7535 (South Africa); Madau, Piero [Department of Astronomy and Astrophysics, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States); Ford, Amanda B. [Astronomy Department, University of Arizona, Tucson, AZ 85721 (United States); Peeples, Molly S., E-mail: jak@obs.carnegiescience.edu [Space Telescope Science Institute, Baltimore, MD 21218 (United States)

    2014-07-10

    We examine the statistics of the low-redshift Ly? forest from smoothed particle hydrodynamic simulations in light of recent improvements in the estimated evolution of the cosmic ultraviolet background (UVB) and recent observations from the Cosmic Origins Spectrograph (COS). We find that the value of the metagalactic photoionization rate (?{sub HI}) required by our simulations to match the observed properties of the low-redshift Ly? forest is a factor of five larger than the value predicted by state-of-the art models for the evolution of this quantity. This mismatch in ?{sub HI} results in the mean flux decrement of the Ly? forest being overpredicted by at least a factor of two (a 10? discrepancy with observations) and a column density distribution of Ly? forest absorbers systematically and significantly elevated compared to observations over nearly two decades in column density. We examine potential resolutions to this mismatch and find that either conventional sources of ionizing photons (galaxies and quasars) must contribute considerably more than current observational estimates or our theoretical understanding of the low-redshift universe is in need of substantial revision.

  3. "Ask Argonne" - Charlie Catlett, Computer Scientist, Part 2

    SciTech Connect (OSTI)

    Catlett, Charlie

    2014-06-17

    A few weeks back, computer scientist Charlie Catlett talked a bit about the work he does and invited questions from the public during Part 1 of his "Ask Argonne" video set (http://bit.ly/1joBtzk). In Part 2, he answers some of the questions that were submitted. Enjoy!

  4. NREL Analysis Insights: Renewable Energy On The Grid, Redefining...

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

    ... A P R I L 2 0 1 5 A N A LY S I S I N S I G H T S Flexible Load - Demand Response Resources Demand response (DR) is a load management practice of deliberately reducing or adding ...

  5. A SPECTROSCOPIC SEARCH FOR LEAKING LYMAN CONTINUUM AT z {approx} 0.7

    SciTech Connect (OSTI)

    Bridge, Carrie R.; Siana, Brian; Salvato, Mara; Rudie, Gwen C.; Teplitz, Harry I.; Scarlata, Claudia; Colbert, James; Armus, Lee; Conselice, Christopher J.; Ferguson, Henry C.; Brown, Thomas M.; Giavalisco, Mauro; De Mello, Duilia F.; Gardner, Jonathan P.

    2010-09-01

    We present the results of rest-frame, UV slitless spectroscopic observations of a sample of 32 z {approx} 0.7 Lyman break galaxy (LBG) analogs in the COSMOS field. The spectroscopic search was performed with the Solar Blind Channel on the Hubble Space Telescope. We report the detection of leaking Lyman continuum (LyC) radiation from an active galactic nucleus-starburst composite. While we find no direct detections of LyC emission in the remainder of our sample, we achieve individual lower limits (3{sigma}) of the observed non-ionizing UV-to-LyC flux density ratios, f{sub {nu}} (1500 A)/f{sub {nu}}(830 A) of 20 to 204 (median of 73.5) and 378.7 for the stack. Assuming an intrinsic Lyman break of 3.4 and an intergalactic medium transmission of LyC photons along the line of sight to the galaxy of 85%, we report an upper limit for the relative escape fraction in individual galaxies of 0.02-0.19 and a stacked 3{sigma} upper limit of 0.01. We find no indication of a relative escape fraction near unity as seen in some LBGs at z {approx} 3. Our UV spectra achieve the deepest limits to date at any redshift for the escape fraction in individual sources. The contrast between these z {approx} 0.7 low escape fraction LBG analogs with z {approx} 3 LBGs suggests that either the processes conducive to high f{sub esc} are not being selected for in the z {approx}< 1 samples or the average escape fraction is decreasing from z {approx} 3 to z {approx} 1. We discuss possible mechanisms that could affect the escape of LyC photons.

  6. Walk the Line: The Development of Route Selection Standards for Spent Nuclear Fuel and High-level Radioactive Waste in the United States - 13519

    SciTech Connect (OSTI)

    Dilger, Fred; Halstead, Robert J.; Ballard, James D.

    2013-07-01

    Although storage facilities for spent nuclear fuel (SNF) and high-level radioactive waste (HLRW) are widely dispersed throughout the United States, these materials are also relatively concentrated in terms of geographic area. That is, the impacts of storage occur in a very small geographic space. Once shipments begin to a national repository or centralized interim storage facility, the impacts of SNF and HLRW will become more geographically distributed, more publicly visible, and almost certainly more contentious. The selection of shipping routes will likely be a major source of controversy. This paper describes the development of procedures, regulations, and standards for the selection of routes used to ship spent nuclear fuel and high-level radioactive waste in the United States. The paper begins by reviewing the circumstances around the development of HM-164 routing guidelines. The paper discusses the significance of New York City versus the Department of Transportation and application of HM-164. The paper describes the methods used to implement those regulations. The paper will also describe the current HM-164 designated routes and will provide a summary data analysis of their characteristics. This analysis will reveal the relatively small spatial scale of the effects of HM 164. The paper will then describe subsequent developments that have affected route selection for these materials. These developments include the use of 'representative routes' found in the Department of Energy (DOE) 2008 Supplemental Environmental Impact Statement for the formerly proposed Yucca Mountain geologic repository. The paper will describe recommendations related to route selection found in the National Academy of Sciences 2006 report Going the Distance, as well as recommendations found in the 2012 Final Report of the Blue Ribbon Commission on America's Nuclear Future. The paper will examine recently promulgated federal regulations (HM-232) for selection of rail routes for hazardous materials transport. The paper concludes that while the HM 164 regime is sufficient for certain applications, it does not provide an adequate basis for a national plan to ship spent nuclear fuel and high-level radioactive waste to centralized storage and disposal facilities over a period of 30 to 50 years. (authors)

  7. Conceptual study of measures against heat generation for TRU fuel fabrication system

    SciTech Connect (OSTI)

    Kawaguchi, Koichi; Namekawa, Takashi

    2007-07-01

    To lower the reprocessing cost and the environmental burden, the Japan Atomic Energy Agency (JAEA) has developed low decontamination TRU fuel fabrication system. TRU fuel contains MA of 1.2 to 5 wt% and its decay heat is estimated a few tens W/kg-HM. As the heat affects fuel quality through oxidation of fuel material and members, it is necessary to remove decay heat. In this work, authors designed concepts of the measures against heat generation at typical equipments using with the thermal hydraulics analysis technique. As a result, it is shown that it is possible to cool fuel materials with specific heat generation up to 20 W/kg-HM enough, though more detailed study is required for comprehensive equipments. (authors)

  8. A new phase in palladium hydride technology

    SciTech Connect (OSTI)

    Walters, R.T.

    1991-12-31

    Two plateaux are observed in both the absorption and desorption isotherms of palladium hydride. For the absorption isotherm, a change in plateau pressure is observed at a hydrogen-to-metal (H/M) ratio of about 0.35 for all temperatures studied. For the desorption isotherm, the change in plateau pressure appears to be a function of temperature, ranging from an H/M ratio of 0.18 at 80{degrees}C to 0.3 at 140{degrees}C. These data are interpreted as being experimentally observed boundaries to an equilibrium phase line located in the miscibility gap of the palladium/hydrogen phase diagram. This new phase does not appear to be a stoichiometric compounds, but rather its composition seems to vary with temperature. 6 refs., 4 figs.

  9. A new phase in palladium hydride technology

    SciTech Connect (OSTI)

    Walters, R.T.

    1991-01-01

    Two plateaux are observed in both the absorption and desorption isotherms of palladium hydride. For the absorption isotherm, a change in plateau pressure is observed at a hydrogen-to-metal (H/M) ratio of about 0.35 for all temperatures studied. For the desorption isotherm, the change in plateau pressure appears to be a function of temperature, ranging from an H/M ratio of 0.18 at 80{degrees}C to 0.3 at 140{degrees}C. These data are interpreted as being experimentally observed boundaries to an equilibrium phase line located in the miscibility gap of the palladium/hydrogen phase diagram. This new phase does not appear to be a stoichiometric compounds, but rather its composition seems to vary with temperature. 6 refs., 4 figs.

  10. September 2015 Most Viewed Documents for Physics | OSTI, US Dept of Energy,

    Office of Scientific and Technical Information (OSTI)

    Office of Scientific and Technical Information September 2015 Most Viewed Documents for Physics Plastic Gamma Sensors: An Application in Detection of Radioisotopes S. Mukhopadhyay (2003) 123 Cathodic arc plasma deposition Anders, Andre (2002) 105 Energy level structure and transition probabilities in the spectra of the trivalent lanthanides in LaF/sub 3/. [Tables, diagrams] Carnall, W.T.; Crosswhite, H.; Crosswhite, H.M. (1978) 103 Synchrotron power supply light source note Fathizadeh, M.

  11. DETECTION OF $sup 54$Mn IN FOOD SAMPLES (Journal Article) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    DETECTION OF $sup 54$Mn IN FOOD SAMPLES Citation Details In-Document Search Title: DETECTION OF $sup 54$Mn IN FOOD SAMPLES Authors: Neilson, H. ; Yakabe, H.M. Publication Date: 1966-01-01 OSTI Identifier: 4590897 Resource Type: Journal Article Resource Relation: Journal Name: Health Physics (England); Journal Volume: Vol: 12; Other Information: Orig. Receipt Date: 31-DEC-66 Research Org: Food and Drug Administration, Washington, D.C. Country of Publication: Country unknown/Code not available

  12. Slide 1

    Office of Scientific and Technical Information (OSTI)

    Rapid Field Measurement of Dissolved Inorganic Carbon Based on CO 2 Analysis VESPER, DJ 1 , EDENBORN, HM 2 (1) Dept. of Geology and Geography, West Virginia University, Morgantown, WV 26506, (2) Geosciences Division, National Energy Technology Lab; U.S. Department of Energy, P.O. Box 10940, Pittsburgh, PA 15236. Paper #210840 Dissolved inorganic carbon (DIC) is commonly measured in water and is an important parameter for understanding carbonate equilibrium, carbon cycling, and water-rock

  13. December 2015 Most Viewed Documents for Physics | OSTI, US Dept of Energy,

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

    Office of Scientific and Technical Information Physics Cathodic arc plasma deposition Anders, Andre (2002) 147 Synchrotron power supply light source note Fathizadeh, M. (1991) 114 Plastic Gamma Sensors: An Application in Detection of Radioisotopes S. Mukhopadhyay (2003) 112 Energy level structure and transition probabilities in the spectra of the trivalent lanthanides in LaF/sub 3/. [Tables, diagrams] Carnall, W.T.; Crosswhite, H.; Crosswhite, H.M. (1978) 93 Selected component failure rate

  14. June 2015 Most Viewed Documents for Physics | OSTI, US Dept of Energy,

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

    Office of Scientific and Technical Information June 2015 Most Viewed Documents for Physics Cathodic arc plasma deposition Anders, Andre (2002) 118 Plastic Gamma Sensors: An Application in Detection of Radioisotopes S. Mukhopadhyay (2003) 93 Energy level structure and transition probabilities in the spectra of the trivalent lanthanides in LaF/sub 3/. [Tables, diagrams] Carnall, W.T.; Crosswhite, H.; Crosswhite, H.M. (1978) 89 Modification to the Monte Carlo N-Particle (MCNP) Visual Editor

  15. Cyber Securing Control Systems

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

    Industrial Control Systems Integration into the DoD Networks A Briefing in Response to House Report 113-102, Accompanying the FY14 National Defense Authorization Act Unclassified - Distribution Statement A August, 2015 Cyber Securing Control Systems Acquisition, Technology and Logistics 2 DoD Scope of Platform IT & Control Systems * Acquisitions / Weapon Systems - H,M & E (ships / subs, missiles, UVs, etc.) - Training Simulators, 3D printing, etc. * EI&E - Buildings & linear

  16. Regulatory compliance guide for DOT-7A type A packaging design

    SciTech Connect (OSTI)

    Kelly, D.L.

    1996-06-04

    The purpose of this guide is to provide instruction for assuring that the regulatory design requirements for a DOT-7A Type A packaging are met. This guide also supports the testing and evaluation activities that are performed on new packaging designs by a DOE-approved test facility through the DOE`s DOT-7A Test Program. This Guide was updated to incorporate regulatory changes implemented by HM-169A (49 CFR, `Transportation`).

  17. Most Viewed Documents for Physics: December 2014 | OSTI, US Dept of Energy,

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

    Office of Scientific and Technical Information Most Viewed Documents for Physics: December 2014 Cathodic arc plasma deposition Anders, Andre (2002) 57 Plastic Gamma Sensors: An Application in Detection of Radioisotopes S. Mukhopadhyay (2003) 48 Klystron beam-bunching lecture Carlsten, B. (1996) 46 Energy level structure and transition probabilities in the spectra of the trivalent lanthanides in LaF/sub 3/. [Tables, diagrams] Carnall, W.T.; Crosswhite, H.; Crosswhite, H.M. (1978) 45

  18. THRESHOLD RADIOACTIVITY FOR BULK FOOD SAMPLES BY GAMMA SPECTROSCOPY

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect THRESHOLD RADIOACTIVITY FOR BULK FOOD SAMPLES BY GAMMA SPECTROSCOPY Citation Details In-Document Search Title: THRESHOLD RADIOACTIVITY FOR BULK FOOD SAMPLES BY GAMMA SPECTROSCOPY Authors: Yakabe, H.M. ; Neilson, H. Publication Date: 1965-02-01 OSTI Identifier: 4654936 Resource Type: Journal Article Resource Relation: Journal Name: J. Assoc. Offic. Agr. Chemists; Journal Volume: Vol: 48; Other Information: Orig. Receipt Date: 31-DEC-65 Research Org: Div. of

  19. Wakefield and RF Kicks Due to Coupler Asymmetry in TESLA-Type Accelerating Cavities

    SciTech Connect (OSTI)

    Bane, K.L.F.; Adolphsen, C.; Li, Z.; /SLAC; Dohlus, M.; Zagorodnov, I.; /DESY; Gonin, I.; Lunin, A.; Solyak, N.; Yakovlev, V.; /Fermilab; Gjonaj, E.; Weiland, T.; /Darmstadt, Tech. Hochsch.

    2008-07-07

    In a future linear collider, such as the International Linear Collider (ILC), trains of high current, low emittance bunches will be accelerated in a linac before colliding at the interaction point. Asymmetries in the accelerating cavities of the linac will generate fields that will kick the beam transversely and degrade the beam emittance and thus the collider performance. In the main linac of the ILC, which is filled with TESLA-type superconducting cavities, it is the fundamental (FM) and higher mode (HM) couplers that are asymmetric and thus the source of such kicks. The kicks are of two types: one, due to (the asymmetry in) the fundamental RF fields and the other, due to transverse wakefields that are generated by the beam even when it is on axis. In this report we calculate the strength of these kicks and estimate their effect on the ILC beam. The TESLA cavity comprises nine cells, one HM coupler in the upstream end, and one (identical, though rotated) HM coupler and one FM coupler in the downstream end (for their shapes and location see Figs. 1, 2) [1]. The cavity is 1.1 m long, the iris radius 35 mm, and the coupler beam pipe radius 39 mm. Note that the couplers reach closer to the axis than the irises, down to a distance of 30 mm.

  20. Africa: the emphasis is exploration

    SciTech Connect (OSTI)

    Not Available

    1980-08-15

    Individual country reports on drilling, oil and gas production, and petroleum exploration and reserves are given for Africa. Nigeria was the continent's largest oil producer in 1979, averaging 2.3 million bpd, followed closely by Libya with 2.07 million bpd. Algeria cut production of crude oil in 1979 to a level of 1,194,350 bpd, and increased gas production to 2031 mmcfd. In Egypt, the return of Israeli-occupied oil fields and a surge in productive capacity enabled production averaging 524,000 bpd. Brief country reports are included for Gabon, Angola, Republic of the Congo, Cameroun, Tunisia, Morocco, Zaire, Ivory Coast, Ghana, Niger, Chad, Republic of South Africa, Sudan, Tanzania, Equatorial Guinea, Seychelles Islands, Mauritania, Republic of Mali, Benin, Kenya, Madagascar, Botswana, Gambia, Mozambique, and Senegal.

  1. Net Imports of Total Crude Oil and Products into the U.S. by Country

    Gasoline and Diesel Fuel Update (EIA)

    2010 2011 2012 2013 2014 2015 View History Total All Countries 9,441 8,450 7,393 6,237 5,065 4,651 1973-2015 Persian Gulf 1,705 1,842 2,149 1,988 1,861 1,496 1993-2015 OPEC* 4,787 4,429 4,093 3,483 2,996 2,652 1993-2015 Algeria 510 355 241 108 109 105 1993-2015 Angola 393 346 233 215 154 136 1993-2015 Ecuador 135 147 117 153 116 104 1993-2015 Iran 0 0 1993-2014 Iraq 415 459 476 341 369 229 1996-2015 Kuwait 197 191 305 328 311 206 1993-2015 Libya 70 15 60 58 5 7 2004-2015 Nigeria 1,006 803 419

  2. Word Pro - S11

    Gasoline and Diesel Fuel Update (EIA)

    66 U.S. Energy Information Administration / Monthly Energy Review February 2016 Table 11.1a World Crude Oil Production: OPEC Members (Thousand Barrels per Day) Algeria Angola Ecuador Iran Iraq Kuwait a Libya Nigeria Qatar Saudi Arabia a United Arab Emirates Vene- zuela Total OPEC b 1973 Average .................... 1,097 162 209 5,861 2,018 3,020 2,175 2,054 570 7,596 1,533 3,366 29,661 1975 Average .................... 983 165 161 5,350 2,262 2,084 1,480 1,783 438 7,075 1,664 2,346 25,790 1980

  3. East Coast (PADD 1) Distillate Fuel Oil Imports

    Gasoline and Diesel Fuel Update (EIA)

    Jul-15 Aug-15 Sep-15 Oct-15 Nov-15 Dec-15 View History All Countries 104 104 76 92 133 130 1981-2015 Persian Gulf 1995-2015 OPEC* 10 1993-2015 Algeria 1994-2010 Angola 1995-2003 Kuwait 1995-2012 Libya 2013-2013 Nigeria 10 1993-2015 Qatar 1995-2015 Saudi Arabia 1995-2015 United Arab Emirates 1995-2014 Venezuela 1993-2014 Non OPEC* 104 104 76 92 133 120 1993-2015 Argentina 1995-2015 Aruba 2005-2012 Bahamas 1994-2014 Bahrain 1995-2007 Belarus 2006-2009 Belgium 1995-2015 Brazil 1994-2014 Cameroon

  4. SPECIAL SEMINAR - The NOTTE experiment, or how to become a Total Solar Eclipse chaser

    SciTech Connect (OSTI)

    2011-02-08

    The NOTTE experiment (Neutrino Oscillations with Telescope during Total Eclipse) aims at searching for visible photons emitted through a possible radiative decay of solar neutrinos. The experiment and the expeditions organized by a group of physicists and astrophysicists from INFN and INAF Bologna hunting for Total Solar Eclipses from 1998 to 2006 wil be described. The results of observations performed during total solar eclipse expeditions in 2001 (Zambia) and 2006 (Sahara desert, Libya) are presented and a beautiful photo gallery will be shown. Other peculiar observations that can be made during a solar eclipse are also illustrated. The seminar will be followed by a brief presentation of future camps for solar eclipse chasers and scientists organized in 2008 in Russia, Kazakhstan, China and Mongolia, in 2009 in Shanghai and on the Easter Island in 2010.

  5. SPECIAL SEMINAR - The NOTTE experiment, or how to become a Total Solar Eclipse chaser

    ScienceCinema (OSTI)

    None

    2011-10-06

    The NOTTE experiment (Neutrino Oscillations with Telescope during Total Eclipse) aims at searching for visible photons emitted through a possible radiative decay of solar neutrinos. The experiment and the expeditions organized by a group of physicists and astrophysicists from INFN and INAF Bologna hunting for Total Solar Eclipses from 1998 to 2006 wil be described. The results of observations performed during total solar eclipse expeditions in 2001 (Zambia) and 2006 (Sahara desert, Libya) are presented and a beautiful photo gallery will be shown. Other peculiar observations that can be made during a solar eclipse are also illustrated. The seminar will be followed by a brief presentation of future camps for solar eclipse chasers and scientists organized in 2008 in Russia, Kazakhstan, China and Mongolia, in 2009 in Shanghai and on the Easter Island in 2010.

  6. Latest Jurassic-early Cretaceous regressive facies, northeast Africa craton

    SciTech Connect (OSTI)

    van Houten, F.B.

    1980-06-01

    Nonmarine to paralic detrital deposits accumulated in six large basins between Algeria and the Arabo-Nubian shield during major regression in latest Jurassic and Early Cretaceous time. The Ghadames Sirte (north-central Libya), and Northern (Egypt) basins lay along the cratonic margin of northeastern Africa. The Murzuk, Kufra, and Southern (Egypt) basins lay in the south within the craton. Data for reconstructing distribution, facies, and thickness of relevant sequences are adequate for the three northern basins only. High detrital influx near the end of Jurassic time and in mid-Cretaceous time produced regressive nubian facies composed largely of low-sinuosity stream and fahdelta deposits. In the west and southwest the Ghadames, Murzuk, and Kufra basins were filled with a few hundred meters of detritus after long-continued earlier Mesozoic aggradation. In northern Egypt the regressive sequence succeeded earlier Mesozoic marine sedimentation; in the Sirte and Southern basins correlative deposits accumulated on Precambrian and Variscan terranes after earlier Mesozoic uplift and erosion. Waning of detrital influx into southern Tunisia and adjacent Libya in the west and into Israel in the east initiated an Albian to early Cenomanian transgression of Tethys. By late Cenomanian time it had flooded the entire cratonic margin, and spread southward into the Murzuk and Southern basins, as well as onto the Arabo-Nubian shield. Latest Jurassic-earliest Cretaceous, mid-Cretaceous, and Late Cretaceous transgressions across northeastern Africa recorded in these sequences may reflect worldwide eustatic sea-level rises. In contrast, renewed large supply of detritus during each regression and a comparable subsidence history of intracratonic and marginal basins imply regional tectonic control. 6 figures.

  7. Theoretical model for plasma expansion generated by hypervelocity impact

    SciTech Connect (OSTI)

    Ju, Yuanyuan; Zhang, Qingming Zhang, Dongjiang; Long, Renrong; Chen, Li; Huang, Fenglei; Gong, Zizheng

    2014-09-15

    The hypervelocity impact experiments of spherical LY12 aluminum projectile diameter of 6.4?mm on LY12 aluminum target thickness of 23?mm have been conducted using a two-stage light gas gun. The impact velocity of the projectile is 5.2, 5.7, and 6.3?km/s, respectively. The experimental results show that the plasma phase transition appears under the current experiment conditions, and the plasma expansion consists of accumulation, equilibrium, and attenuation. The plasma characteristic parameters decrease as the plasma expands outward and are proportional with the third power of the impact velocity, i.e., (T{sub e}, n{sub e})???v{sub p}{sup 3}. Based on the experimental results, a theoretical model on the plasma expansion is developed and the theoretical results are consistent with the experimental data.

  8. MEMQRANDUM

    Office of Legacy Management (LM)

    ,:?' _. .,. (p. z-3 ;: = 381 I!.0 MEMQRANDUM TO: FILE DATE +a& 7 -- -_ --------____ FROM: SUBJECT: SITE NAME: C ALTERNATE --------------'------------------------ OdYS NAME: -------------____-____ CITY: GOIS, STATE: -------- ----------------- c= OWNER(S) ------__ Past: c 36C~ Current: c, dfS --------- ----------- -------------------------- 'Owner contacted yes IJ no; if yes, date contacted_lySj 0 7 t(-zN/tr/y) TYPE OF OPERATION -----------______ 0 Research & Development 0 Production scale

  9. A LYMAN BREAK GALAXY IN THE EPOCH OF REIONIZATION FROM HUBBLE SPACE TELESCOPE GRISM SPECTROSCOPY

    SciTech Connect (OSTI)

    Rhoads, James E.; Malhotra, Sangeeta; Cohen, Seth; Zheng Zhenya; Stern, Daniel; Dickinson, Mark; Pirzkal, Norbert; Grogin, Norman; Koekemoer, Anton; Peth, Michael A.; Spinrad, Hyron; Reddy, Naveen; Hathi, Nimish; Budavari, Tamas; Ferreras, Ignacio; Gardner, Jonathan P.; Gronwall, Caryl; Haiman, Zoltan; Kuemmel, Martin; Meurer, Gerhardt; and others

    2013-08-10

    We present observations of a luminous galaxy at z = 6.573-the end of the reionization epoch-which has been spectroscopically confirmed twice. The first spectroscopic confirmation comes from slitless Hubble Space Telescope Advanced Camera for Surveys grism spectra from the PEARS survey (Probing Evolution And Reionization Spectroscopically), which show a dramatic continuum break in the spectrum at rest frame 1216 A. The second confirmation is done with Keck + DEIMOS. The continuum is not clearly detected with ground-based spectra, but high wavelength resolution enables the Ly{alpha} emission line profile to be determined. We compare the line profile to composite line profiles at z = 4.5. The Ly{alpha} line profile shows no signature of a damping wing attenuation, confirming that the intergalactic gas is ionized at z = 6.57. Spectra of Lyman breaks at yet higher redshifts will be possible using comparably deep observations with IR-sensitive grisms, even at redshifts where Ly{alpha} is too attenuated by the neutral intergalactic medium to be detectable using traditional spectroscopy from the ground.

  10. Mechanism and computational model for Lyman-{alpha}-radiation generation by high-intensity-laser four-wave mixing in Kr-Ar gas

    SciTech Connect (OSTI)

    Louchev, Oleg A.; Saito, Norihito; Wada, Satoshi; Bakule, Pavel; Yokoyama, Koji; Ishida, Katsuhiko; Iwasaki, Masahiko

    2011-09-15

    We present a theoretical model combined with a computational study of a laser four-wave mixing process under optical discharge in which the non-steady-state four-wave amplitude equations are integrated with the kinetic equations of initial optical discharge and electron avalanche ionization in Kr-Ar gas. The model is validated by earlier experimental data showing strong inhibition of the generation of pulsed, tunable Lyman-{alpha} (Ly-{alpha}) radiation when using sum-difference frequency mixing of 212.6 nm and tunable infrared radiation (820-850 nm). The rigorous computational approach to the problem reveals the possibility and mechanism of strong auto-oscillations in sum-difference resonant Ly-{alpha} generation due to the combined effect of (i) 212.6-nm (2+1)-photon ionization producing initial electrons, followed by (ii) the electron avalanche dominated by 843-nm radiation, and (iii) the final breakdown of the phase matching condition. The model shows that the final efficiency of Ly-{alpha} radiation generation can achieve a value of {approx}5x10{sup -4} which is restricted by the total combined absorption of the fundamental and generated radiation.

  11. A DEEP HUBBLE SPACE TELESCOPE SEARCH FOR ESCAPING LYMAN CONTINUUM FLUX AT z {approx} 1.3: EVIDENCE FOR AN EVOLVING IONIZING EMISSIVITY

    SciTech Connect (OSTI)

    Siana, Brian; Bridge, Carrie R.; Teplitz, Harry I.; Chary, Ranga-Ram; Colbert, James W.; Scarlata, Claudia; Ferguson, Henry C.; Brown, Thomas M.; Giavalisco, Mauro; Dickinson, Mark; De Mello, Duilia F.; Conselice, Christopher J.; Gardner, Jonathan P.

    2010-11-01

    We have obtained deep Hubble Space Telescope far-UV images of 15 starburst galaxies at z {approx} 1.3 in the GOODS fields to search for escaping Lyman continuum (LyC) photons. These are the deepest far-UV images (m{sub AB} = 28.7, 3{sigma}, 1'' diameter) over this large an area (4.83 arcmin{sup 2}) and provide some of the best escape fraction constraints for any galaxies at any redshift. We do not detect any individual galaxies, with 3{sigma} limits to the LyC ({approx}700 A) flux 50-149 times fainter (in f{sub {nu}}) than the rest-frame UV (1500 A) continuum fluxes. Correcting for the mean intergalactic medium (IGM) attenuation (factor {approx}2), as well as an intrinsic stellar Lyman break (factor {approx}3), these limits translate to relative escape fraction limits of f{sub esc,rel} < [0.03, 0.21]. The stacked limit is f{sub esc,rel}(3{sigma}) < 0.02. We use a Monte Carlo simulation to properly account for the expected distribution of line-of-sight IGM opacities. When including constraints from previous surveys at z {approx} 1.3 we find that, at the 95% confidence level, no more than 8% of star-forming galaxies at z {approx} 1.3 can have relative escape fractions greater than 0.50. Alternatively, if the majority of galaxies have low, but non-zero, escaping LyC, the escape fraction cannot be more than 0.04. In light of some evidence for strong LyC emission from UV-faint regions of Lyman break galaxies (LBGs) at z {approx} 3, we also stack sub-regions of our galaxies with different surface brightnesses and detect no significant LyC flux at the f{sub esc,rel} < 0.03 level. Both the stacked limits and the limits from the Monte Carlo simulation suggest that the average ionizing emissivity (relative to non-ionizing UV emissivity) at z {approx} 1.3 is significantly lower than has been observed in LBGs at z {approx} 3. If the ionizing emissivity of star-forming galaxies is in fact increasing with redshift, it would help to explain the high photoionization rates seen in the IGM at z>4 and reionization of the IGM at z>6.

  12. The correlation between reactivity and ash mineralogy of coke

    SciTech Connect (OSTI)

    Kerkkonen, O.; Mattila, E.; Heiniemi, R.

    1996-12-31

    Rautaruukki is a modern integrated Finnish steel works having a production of 2.4 mil. t/year of flat products. The total fuel consumption of the two blast furnaces in 1994 was 435 kg/t HM. Coke used was 345 kg/t HM and oil injection was 90 kg/t HM. The coking plant was taken in to operation in 1987 and is the only one in Finland, which means that the coking tradition is very short. Coke production is 0.9 mil. t/year. The coking blends include 70--80% medium volatile coals having a wide range of total dilatation. From time to time disturbances in the operation of the blast furnaces have occurred in spite of the fact that the reactivity of the coke used has remained constant or even decreased. It was thought necessary to investigate the factors affecting coke reactivity, in order to better understand the results of the reactivity test. This paper deals with carbonization tests done in a 7 kg test oven using nine individual coals having volatile-matter contents of 17--36% (dry) and seven blends made from these coals. Coke reactivity with CO{sub 2} at 1100 C (CRI) and coke strength after reaction (CSR) were determined using the test developed by the Nippon Steel Corporation. The influence of coke carbon form, porosity and especially ash mineralogy on the coke reactivity were examined. The effects of some additives; petroleum coke (pet coke), the spillage material from the coke ovens and oxidized coal, on coke quality were also studied. Typical inorganic minerals found in coals were added to one of the high volatile coals, which was then coked to determine the affect of the minerals on the properties of the coke produced.

  13. TASK PLAN: Tribal Issues Topic Group

    Office of Environmental Management (EM)

    Task Plan 1 Tribal Issues Topic Group 7/12/00 Task Plan 1 Page 1 Status: Active DOE Lead: National Transportation Program (NTP-AL; Judith Holm @ 505-845-4767) Start Date: January 1998 End Date: TBD Subject: TEC Topic Group - Tribal Issues rpose: To address issues such as: (1) HM-164 as it relates to Tribes; (2) to complete the Tribal column of the Rail Topic Group Regulatory Matrix; (3) to determine Tribal authority to stop and inspect shipments of radioactive materials; (4) to provide tribal

  14. Comprehensive Energy Assessment: EE and RE Project Optimization Modeling for United States Pacific Command (USPACOM) American Recovery and Reinvestment Act (ARRA) FEMP Technical Assistance

    SciTech Connect (OSTI)

    Brigantic, Robert T.; Papatyi, Anthony F.; Perkins, Casey J.

    2010-09-30

    This report summarizes a study and corresponding model development conducted in support of the United States Pacific Command (USPACOM) as part of the Federal Energy Management Program (FEMP) American Reinvestment and Recovery Act (ARRA). This research was aimed at developing a mathematical programming framework and accompanying optimization methodology in order to simultaneously evaluate energy efficiency (EE) and renewable energy (RE) opportunities. Once developed, this research then demonstrated this methodology at a USPACOM installation - Camp H.M. Smith, Hawaii. We believe this is the first time such an integrated, joint EE and RE optimization methodology has been constructed and demonstrated.

  15. Temperature and epi thickness dependence of the heavy ion induced latchup threshold for a CMOS/epi 16K static RAM

    SciTech Connect (OSTI)

    Smith, L.S.; Nichols, D.K.; Coss, J.R.; Price, W.E.; Binder, D.

    1987-12-01

    Data have been obtained with krypton and xenon ions for the latchup threshold vs. temperature of four different versions of a Harris CMOS/epi 16K static RAM. These special versions of the HM6516 RAM have 12-micron, 9-micron, 7-micron and 5-micron epi thicknesses, as grown. The test data showed a marked improvement in latchup resistance with decreasing epi thickness and with decreasing temperature over the range of 25/sup 0/C (operating chip ambient) to 100/sup 0/C.s.

  16. PROBING THE SOLAR WIND ACCELERATION REGION WITH THE SUN-GRAZING COMET C/2002 S2

    SciTech Connect (OSTI)

    Giordano, S.; Raymond, J. C.; Lamy, P.; Uzzo, M.; Dobrzycka, D.

    2015-01-01

    Comet C/2002 S2, a member of the Kreutz family of sungrazing comets, was discovered in white-light images of the Large Angle and Spectromeric Coronagraph Experiment coronagraph on the Solar and Heliospheric Observatory (SOHO) on 2002 September 18 and observed in H I Ly? emission by the SOHO Ultraviolet Coronagraph Spectrometer (UVCS) instrument at four different heights as it approached the Sun. The H I Ly? line profiles detected by UVCS are analyzed to determine the spectral parameters: line intensity, width, and Doppler shift with respect to the coronal background. Two-dimensional comet images of these parameters are reconstructed at the different heights. A novel aspect of the observations of this sungrazing comet data is that, whereas the emission from most of the tail is blueshifted, that along one edge of the tail is redshifted. We attribute these shifts to a combination of solar wind speed and interaction with the magnetic field. In order to use the comet to probe the density, temperature, and speed of the corona and solar wind through which it passes, as well as to determine the outgassing rate of the comet, we develop a Monte Carlo simulation of the H I Ly? emission of a comet moving through a coronal plasma. From the outgassing rate, we estimate a nucleus diameter of about 9 m. This rate steadily increases as the comet approaches the Sun, while the optical brightness decreases by more than a factor of 10 and suddenly recovers. This indicates that the optical brightness is determined by the lifetimes of the grains, sodium atoms, and molecules produced by the comet.

  17. Intergalactic medium emission observations with the cosmic web imager. I. The circum-QSO medium of QSO 1549+19, and evidence for a filamentary gas inflow

    SciTech Connect (OSTI)

    Martin, D. Christopher; Chang, Daphne; Matuszewski, Matt; Morrissey, Patrick; Rahman, Shahin; Moore, Anna; Steidel, Charles C.

    2014-05-10

    The Palomar Cosmic Web Imager (PCWI), an integral field spectrograph designed to detect and map low surface brightness emission, has obtained imaging spectroscopic maps of Ly? from the circum-QSO medium (CQM) of QSO HS1549+19 at redshift z = 2.843. Extensive extended emission is detected from the CQM, consistent with fluorescent and pumped Ly? produced by the ionizing and Ly? continuum of the QSO. Many features present in PCWI spectral images match those detected in narrow-band images. Filamentary structures with narrow line profiles are detected in several cases as long as 250-400 kpc. One of these is centered at a velocity redshifted with respect to the systemic velocity, and displays a spatially collimated and kinematically cold line profile increasing in velocity width approaching the QSO. This suggests that the filament gas is infalling onto the QSO, perhaps in a cold accretion flow. Because of the strong ionizing flux, the neutral column density is low, typically N(H I)?10{sup 12}--10{sup 15} cm{sup ?2}, and the line center optical depth is also low (typically ?{sub 0} < 10), insufficient to display well separated double peak emission characteristic of higher line optical depths. With a simple ionization and cloud model we can very roughly estimate the total gas mass (log M {sub gas} = 12.5 0.5) and the total (log M {sub tot} = 13.3 0.5). We can also calculate a kinematic mass from the total line profile (2 10{sup 13} M {sub ?}), which agrees with the mass estimated from the gas emission. The intensity-binned spectrum of the CQM shows a progression in kinematic properties consistent with heirarchical structure formation.

  18. 2page.indd

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

    P D AT E S O U T H W E S T E R N P O W E R A D M I N I S T R A T I O N S U P P L E M E N T A L E D I T I O N J U LY 1 3 , 2 0 0 6 PMA Partnership Implements New SCADA System at Springfield Operations Center Southwestern successfully installed its new Supervisory Control and Data Acquisition (SCADA) system at its Operations Center in Springfield, MO, on June 20, 2006. This new software, developed in cooperation with Western Area Power Administration (Western), essentially replaces the old

  19. 7-9-draft3.indd

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

    Administration, like: Mike Deihl Administrator Tulsa, Oklahoma Special thanks to: Ladell Butts Scott Carpenter Dallas Cooper Linda Dunham Ruben Garcia Tom Green Janet Hagar Gregg Happle William Hiller Sean Long Stan Mason Linda Mummey Beth Nielsen Fritha Ohlson George Robbins Dave Sargent Aiden Smith Jane Thomas Mistie Yost U P D AT E S O U T H W E S T E R N P O W E R A D M I N I S T R A T I O N J U LY - S E P T E M B E R 2 0 0 7 Hilltop Helps Ease Transmission Woes The electricity is flowing a

  20. Assessing

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

    dental disease in minutes Understanding climate change Keeping watch on the world SPRING 2007 S A N D I A T E C H N O L O G Y A Q UA RT E R LY R E S E A R C H & D E V E LO P M E N T MAG A Z I N E - VO LUM E 9 , N O. 1 Sandia Technology (ISSN: 1547-5190) is a quarterly maga- zine published by Sandia National Laboratories. Sandia is a multiprogram engineering and science laboratory operated by Sandia Corporation, a Lockheed Martin company, for the Department of Energy. With main facilities in

  1. One West Third Street Tulsa Oklahoma

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

    Conley Jennings Lineman Springfield, MO Special thanks to: Marshall Boyken Mike Deihl Ruben Garcia Bethel Herrold William Hiller Beth Nielsen George Robbins Gary Swartzlander Cris Van Horn Rutha Williams Jan Woolverton U P D AT E S O U T H W E S T E R N P O W E R A D M I N I S T R A T I O N J U LY - S E P T E M B E R 2 0 0 5 Strategic Workshop Unites Hydropower Community At the invitation of the U.S. Army Corps of Engineers (Corps), Federal power customers joined representatives of the Corps,

  2. wjj42a6.tmp

    National Nuclear Security Administration (NNSA)

    DOIUEA-1300 X4%L!)y The Nevada Test Site Development Corporation's Desert Rock S& Park at the Nevada Test Site United 'StatesDepartment of Energy Nevada Operations Office Las Vegas, Nevada Available for public sale, in paper, from: U.S. Department of Commerce National Technical Information Service 5285 Port Royal Road Sprin@e14 VA 22161 Phone: (800) 553-6847 Fax: (703) 605-6900 Email: orders(i$ntis.fedworldgov Online ordering: ht@-Avww. ntis.govlorderihg. htm Available electronically at

  3. DOE Loan Programs Office Update

    Energy Savers [EERE]

    P E N S O L I C I TAT I O N S | A P P LY N O W IN THIS UPDATE: FEBRUARY 2015 SUPPORTING THE AMERICAN AUTO INDUSTRY UPDATED ATVM LOAN PROGRAM GUIDANCE NEW GREENHOUSE GAS EMISSIONS WORKSHEET CURRENT OPEN SOLICITATIONS SUPPORTING THE FUTURE OF THE AMERICAN AUTO INDUSTRY Last month, President Obama underscored the importance of innovation in the American auto industry during his visit to one of the many factories upgraded with a $5.9 billion loan to the Ford Motor Company through the Advanced

  4. Employment Information Session | Department of Energy

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

    Employment Information Session December 21, 2015 3:30PM to 4:30PM EST Employment Information Session Students and recent graduates will learn about various internship and entry-level opportunities available at the U.S. Department of Energy Date: Monday, December 21, 2015 Time: 3:30-4:30 pm EST Location: Virtual Follow the link: http://bit.ly/1Z8AHJC to register for this session by December 18th All of our programs require U.S. Citizenship. For more information and other eligibility requirements

  5. Analysis Insights, August 2015: Sustainable Transportation (Brochure), NREL (National Renewable Energy Laboratory)

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

    046 A U G U S T 2 0 1 5 A N A LY S I S I N S I G H T S SUSTAINABLE TRANSPORTATION Moving People and Goods in Ways that are Cleaner, Greener, Smarter 2 SUSTAINABLE TRANSPORTATION Moving people and goods from point A to B has never been easier, but our current transportation systems also take a toll on our environment. Transportation currently accounts for 71% of total U.S. petroleum use and 33% of the nation's total carbon emissions. With new technology, can we make our transportation system

  6. Inverse Design of Mn-based ternary p-type wide-gap oxides

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

    ZnO is an important prototypical wide-gap oxide semiconductor. The discrepancy between band- structure theory and ARPES is removed by a correction for the Zn-d band energy in GW calculations. Significance and Impact The present approach improves the capability for property prediction and design of energy materials. Benchmarking Band-Structure Calculations Against Angular-Resolved Photoemission Spectroscopy (ARPES) for ZnO L.Y. Lim, S. Lany, Y.J. Chang, E. Rotenberg, A. Zunger, M.F. Toney,

  7. Tl

    Office of Legacy Management (LM)

    d ' . ,$! li ,' ?I ./ Tl ,,, . * :I _ (.~"O lY Y i, t/ Ye D&J /J )./) $j,J-i ,,.,..____- ~\t, ,Twb EGxG Energy Measurements Group ,&3.3 ;LLi- \\. \ Y. @ WAMD 010 1% L{ 'i:,; November 30, 1979 NY, 5,. j,:,i, we-- #i#~*~ :.a,.,,.,, .I,*,>!: X~? ,, ,,., ,$a>.:.,;, .%' " ,i c"_m.J 6. i< cm I I,., y SUMMARY REPORT AERIAL RADIOLOGICAL SURVEY NIAGARA FALLS AREA NIAGARA FALLS, NEW YORK DATE O F SURVEY: SEPTEMBER 1979 APPROVED FOR DISTRIBUTION: CL. // w----. 7'. -P.

  8. WAR DEPARTaMMeNT

    Office of Legacy Management (LM)

    i ..I WAR DEPARTaMMeNT Imentory~at ~etnl Bydridaa aa of 2i Js+ua?y is 20 toxss Bozml. .' imsntary Of 10 t0z.w allc7fs 10 tom as BX0683. p 5 Production of heels at Ravsre Coppsr & Brass Com_saay: ~ ExLrwion ia axpested to continua at 30 tons par waskand, whioh _ ..-,:~ is squix&mt to 130 tons per average nonth.Bcri;lg Febrmryx ht is estiziited ~.;'i thxt extrusionail be 6% on old specification bilf&a snd 30;; on nsv billets. It is estixstad or:ly nsa apasifioatim billets will be

  9. I~

    Office of Legacy Management (LM)

    __, I,- __.j .^,, ~~.,l~, _I.x__ . ,,,,, ,_^_ ,,_xx,. ,~.__~_x -,-.. _1 ,.,., - I~ .c \ -- - g-' . @ ~--~Z~, Ls-u &. 0 -*,- hiK ,,-& b TO FILE ' = .-. r. AUG 2 9 1945 A~TPPHC~~~ METALS COPUDOP~TIO~ '* ~,ci~ly~1~~ 41 BROAD STREET (In duplicate) November 6, 1942 The District Engineer, u. s . Zngineer Office, Zanhattarn District, P. 0. 30x 4.2, Station P., i?C:: York, X.Y. Attention: Idajo- Thomas T. Crenshav:. Gentlemen: Classification Cancc!!A ZG? ;~yp~~ Follo~5.nS our conversation of

  10. LA-10256-MS

    Office of Legacy Management (LM)

    10256-MS Los Alamos National Laboratory is operated by the University of California for the United States Department of Energy under contract W-7405-ENG-36. Radiological Survey and Evaluation of the Fallout Area fom the Trinity Test: Chupadera Mesa and White Sands Misile Range, New Mexco - ~ ~S1S' :ts rV T Los Alamos National Laboratory Ly© /.aU U UwHjm ©,Los Alamos, New Mexico 87545 An Affirmative Action/Equal Opportunity Employer Prepared by Kathy Derouin, Group HSE-8 DISCLAIMER This report

  11. U.S. NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT

    Office of Legacy Management (LM)

    -., * : . ; * c i. :i; $i 4 5 ' I jr 1 ly i *- 1 U.S. NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT Region I Report No. 078-154-A - Part1 of 2 Subject: Radioactive Material in Norton, Massachusetts Uncontrolled ' :-- . . . _ > Location, Investigation at: Norton and Attleboro, Massachusetts Investigation conducted: November 14, 28-30; December 1, 7, 8, 21, 1978; January 9-12, 1978 Investigators: ?-9,7G Phys'ical Security-Inspector I dati sibntd rl,puet ryyl Ilty Inspector

  12. Lamp Divisions

    Office of Legacy Management (LM)

    --- /A;; i :' r%i;in~house ilEc;' i:Z3:~cra:ion Lamp Divisions , _.. (I +i. 0 :,,,rg. . I . . -= i?e p/q! qe)-' &se pw E.rcale?l iev, Je!sey 07m March 20, 1 gs? ::r . J. A. Jones I ti. 5. Muclear Regulatory Commission .> = ..- haterials Licensing Branch -s - ,.I, - - Division of Fuel Cycle and hateri al Safety LY. , $2 - _ . ' -' . 3 _- - Yeshington, C. C. 2@555 - :_ :--, =-- -- .-?J -.: y...., : :- 7 Dear Mr. Jones : y-- --, ? . *I 2=15 2 r; X -P The following is our final report of the

  13. O Ti-tE LOVE

    Office of Legacy Management (LM)

    ' ItqQtJulRl' IICt' O Ti-tE LOVE ~t?Al. . . At2D Al.CLkTED IChTTEtt~ . ' . . . : . ' . i I . . . . .mr TttE HOt\' ORAULE~ STANLEY FItZl:; SFCAKER ' . : ,J WE\J i' ORti STATE ASSH' rtrLY l r . . isay 29,.1980 Consultant to the Kew York ' , .' .I, " ..' . ,"' ! -. . . : . . . I.. . . . . ~. ,:- 9.. :. .' , * Ill . ,.. , ,i / All . ' %: : . : . . -. ;:. * :... . _ -. .' . . . I . ' J n' f armed. ?%c firtdingo and backup documentatiin embodied in thi preliminafy report compel the Task

  14. THE AEROSPACE CORPORATION

    Office of Legacy Management (LM)

    .55 LyEnfant Plaro. S.W., Washingzon, D.C. 20024.2174, Telephone: (202) 488-6000 7117-03.87.cdy.27 27 May 1987 Mr. 'Andrew Wallo, III, NE:23 Division of Facility & Site Decommissioning Projects U.S. Department of Energy Germantown, Maryland: 20545 Dear Mr. Wallo: I STATUS OF ACTIONS - FUSRAP SITE LIST Aerospace recently completed .a comprehensive review of sites listed in the FUSRAP Site Investigation and Remedial Action Summary Report, dated Uecember 31, 1986. The primary objectives of this

  15. Microsoft Word - DR_benefits_Congress_v9_2 03 06 12pm.doc

    Office of Environmental Management (EM)

    pp u ly Demand Price of Electricity Supply Quantity of Electricity P P DR Q DR Q Demand DR BENEFITS OF DEMAND RESPONSE IN ELECTRICITY MARKETS AND RECOMMENDATIONS FOR ACHIEVING THEM A REPORT TO THE UNITED STATES CONGRESS PURSUANT TO SECTION 1252 OF THE ENERGY POLICY ACT OF 2005 U.S. Department of Energy February 2006 U.S. Department of Energy Benefits of Demand Response and Recommendations ii U.S. Department of Energy Benefits of Demand Response and Recommendations iii The Secretary [of Energy]

  16. 00 cover com_tech

    National Nuclear Security Administration (NNSA)

    pier final project report cec-500-2006-022 Suggested Practices for Avian Protection On Power Lines: The State of the Art in 2006 Avian Power Line Interaction Committee T H I S PA G E I N T E N T I O N A L LY L E F T B L A N K Avian Power Line Interaction Committee pier final project report cec-500-2006-022 Suggested Practices for Avian Protection On Power Lines: The State of the Art in 2006 Prepared by: Avian Power Line Interaction Committee Avian Power Line Interaction Committee Additional

  17. Recent developments in blast furnace process control within British Steel

    SciTech Connect (OSTI)

    Warren, P.W.

    1995-12-01

    British Steel generally operates seven blast furnaces on four integrated works. All furnaces have been equipped with comprehensive instrumentation and data logging computers over the past eight years. The four Scunthorpe furnaces practice coal injection up to 170 kg/tHM (340 lb/THM), the remainder injecting oil at up to 100 kg/tHM (200 lb/THM). Distribution control is effected by Paul Wurth Bell-Less Tops on six of the seven furnaces, and Movable Throat Armour with bells on the remaining one. All have at least one sub burden probe. The blast furnace operator has a vast quantity of data and signals to consider and evaluate when attempting to achieve the objective of providing a consistent supply of hot metal. Techniques have been, and are being, developed to assist the operator to interpret large numbers of signals. A simple operator guidance system has been developed to provide advice, based on current operating procedures and interpreted data. Further development will involve the use of a sophisticated Expert System software shell.

  18. The B*B? coupling using relativistic heavy quarks

    SciTech Connect (OSTI)

    Flynn, J. M.; Fritzsch, P.; Kawanai, T.; Lehner, C.; Samways, B.; Sachrajda, C. T.; Van de Water, R. S.; Witzel, O.

    2015-06-23

    We report on a calculation of the B*B? coupling in lattice QCD. The strong matrix element (B?|B*) is directly related to the leading order low-energy constant in heavy meson chiral perturbation theory (HM?PT) for B mesons. We carry out our calculation directly at the b-quark mass using a non-perturbatively tuned clover action that controls discretization effects of order |p?a| and (ma)n for all n. Our analysis is performed on RBC/UKQCD gauge configurations using domain-wall fermions and the Iwasaki gauge action at two lattice spacings of a1 = 1.729(25) GeV, a1 = 2.281 (28) GeV, and unitary pion masses down to 290 MeV. We achieve good statistical precision and control all systematic uncertainties, giving a final result for the HM?PT coupling gb = 0.56(3)stat(7)sys in the continuum and at the physical light-quark masses. Furthermore, this is the first calculation performed directly at the physical b-quark mass and lies in the region one would expect from carrying out an interpolation between previous results at the charm mass and at the static point.

  19. Why the Gulf War still matters: Foreign perspectives on the war and the future of international security. Report No. 16

    SciTech Connect (OSTI)

    Garrity, P.J.

    1993-07-01

    This report summarizes the main findings of a Center for National Security Studies (CNSS) project that examined how a number of nations other than the United States have reacted to the course and outcome of the Persian Gulf War of 1991. The project was built around studies of key countries on which the Gulf War might reasonably be expected to have had a significant impact: Argentina, the ASEAN states, Brazil, China, Cuba, Egypt, France, Germany, India, Iran, Iraq, Israel, Italy, Japan, Jordan, Libya, North Korea, Russia, Saudi Arabia, South Korea, Spain, Syria, Taiwan, the United Kingdom, Vietnam, and the states of the former Yugoslavia. These country studies were written by well-recognized independent experts following a common set of guidelines provided by CNSS. When the country studies were completed, they were reviewed and supplemented through a series of peer assessments and workshops. The report represents a synthesis of material generated through this process, and is intended to stimulate thought and further analysis on the critical topics discussed herein.

  20. East Coast (PADD 1) Total Crude Oil and Products Imports

    Gasoline and Diesel Fuel Update (EIA)

    2010 2011 2012 2013 2014 2015 View History All Countries 922,432 859,818 727,383 661,835 605,839 627,574 1981-2015 Persian Gulf 32,645 36,655 49,578 36,276 39,750 28,276 1993-2015 OPEC* 297,725 276,478 216,695 191,739 122,057 96,004 1993-2015 Algeria 28,538 27,871 29,164 9,781 6,440 4,234 1993-2015 Angola 44,554 45,631 30,832 30,371 25,299 17,880 1993-2015 Ecuador 550 347 1,813 1,223 411 931 1995-2015 Iraq 8,024 12,382 17,247 3,260 15,112 8,123 1995-2015 Kuwait 325 250 605 591 1995-2014 Libya

  1. Africa gaining importance in world LPG trade

    SciTech Connect (OSTI)

    Haun, R.R.; Otto, K.W.; Whitley, S.C.

    1997-05-12

    Major LPG projects planned or under way in Africa will increase the importance of that region`s presence in world LPG trade. Supplies will nearly double between 1995 and 2005, at which time they will remain steady for at least 10 years. At the same time that exports are leveling, however, increasing domestic demand for PG is likely to reduce export-market participation by Algeria, Nigeria, Egypt, and Libya. The growth of Africa`s participation in world LPG supply is reflected in comparisons for the next 15--20 years. Total world supply of LPG in 1995 was about 165 million metric tons (tonnes), of which Africans share was 7.8 million tonnes. By 2000, world supply will grow to slightly more than 200 million tonnes, with Africa`s share expected to increase to 13.2 million tonnes (6.6%). And by 2005, world LPG supply will reach nearly 230 million tonnes; Africa`s overall supply volumes by that year will be nearly 16.2 million tonnes (7%). World LPG supply for export in 1995 was on order of 44 million tonnes with Africa supply about 4 million tonnes (9%). By 2005, world export volumes of LPG will reach nearly 70 million tonnes; Africa`s share will have grown by nearly 10 million tonnes (14.3%).

  2. World crude output overcomes Persian Gulf disruption

    SciTech Connect (OSTI)

    Not Available

    1992-02-01

    Several OPEC producers made good on their promises to replace 2.7 MMbpd of oil exports that vanished from the world market after Iraq took over Kuwait. Even more incredibly, they accomplished this while a breathtaking 1.2- MMbopd reduction in Soviet output took place during the course of 1991. After Abu Dhabi, Indonesia, Iran, Libya, Nigeria, Saudi Arabia and Venezuela turned the taps wide open, their combined output rose 2.95 MMbopd. Put together with a 282,000-bopd increase by Norway and contributions from smaller producers, this enabled world oil production to remain within 400,000 bopd of its 1990 level. The 60.5-MMbopd average was off by just 0.7%. This paper reports that improvement took place in five of eight regions. Largest increases were in Western Europe and Africa. Greatest reductions occurred in Eastern Europe and the Middle East. Fifteen nations produced 1 MMbopd or more last year, compared with 17 during 1990.

  3. Discovery of eight z ? 6 quasars from Pan-STARRS1

    SciTech Connect (OSTI)

    Baados, E.; Venemans, B. P.; Morganson, E.; Decarli, R.; Walter, F.; Rix, H.-W.; Farina, E. P.; Chambers, K. C.; Morgan, J. S.; Burgett, W. S.; Kaiser, N.; Kudritzki, R.-P.; Fan, X.; McGreer, I.; Jiang, L.; De Rosa, G.; Simcoe, R.; Wei, A.; Price, P. A.; Greiner, J.; and others

    2014-07-01

    High-redshift quasars are currently the only probes of the growth of supermassive black holes and potential tracers of structure evolution at early cosmic time. Here we present our candidate selection criteria from the Panoramic Survey Telescope and Rapid Response System 1 and follow-up strategy to discover quasars in the redshift range 5.7 ? z ? 6.2. With this strategy we discovered eight new 5.7 ? z ? 6.0 quasars, increasing the number of known quasars at z > 5.7 by more than 10%. We additionally recovered 18 previously known quasars. The eight quasars presented here span a large range of luminosities (27.3 ? M {sub 1450} ? 25.4; 19.6 ? z {sub P1} ? 21.2) and are remarkably heterogeneous in their spectral features: half of them show bright emission lines whereas the other half show a weak or no Ly? emission line (25% with rest-frame equivalent width of the Ly? +N V line lower than 15 ). We find a larger fraction of weak-line emission quasars than in lower redshift studies. This may imply that the weak-line quasar population at the highest redshifts could be more abundant than previously thought. However, larger samples of quasars are needed to increase the statistical significance of this finding.

  4. GADRAS isotope ID users manual for analysis of gamma-ray measurements and API for Linux and Android .

    SciTech Connect (OSTI)

    Mitchell, Dean J; Harding, Lee T.

    2014-05-01

    Isotope identification algorithms that are contained in the Gamma Detector Response and Analysis Software (GADRAS) can be used for real-time stationary measurement and search applications on platforms operating under Linux or Android operating sys-tems. Since the background radiation can vary considerably due to variations in natu-rally-occurring radioactive materials (NORM), spectral algorithms can be substantial-ly more sensitive to threat materials than search algorithms based strictly on count rate. Specific isotopes or interest can be designated for the search algorithm, which permits suppression of alarms for non-threatening sources, such as such as medical radionuclides. The same isotope identification algorithms that are used for search ap-plications can also be used to process static measurements. The isotope identification algorithms follow the same protocols as those used by the Windows version of GADRAS, so files that are created under the Windows interface can be copied direct-ly to processors on fielded sensors. The analysis algorithms contain provisions for gain adjustment and energy lineariza-tion, which enables direct processing of spectra as they are recorded by multichannel analyzers. Gain compensation is performed by utilizing photopeaks in background spectra. Incorporation of this energy calibration tasks into the analysis algorithm also eliminates one of the more difficult challenges associated with development of radia-tion detection equipment.

  5. A study on a voloxidizer with an oxygen concentration controller for a scale-up DESIGN

    SciTech Connect (OSTI)

    Kim, Young-Hwan; Yoon, Ji-Sup; Park, Byung-Suk; Jung, Jae-Hoo

    2007-07-01

    For a oxidation of UO{sub 2} pellets of tens/kg in a vol-oxidizer, the existing devices take a long time, also, for their scale-up to an engineering scale, we need the optimum oxygen concentration with an maximum oxidation efficiency. In this study, we attained the optimum oxygen concentration to shorten the oxidation time of a simulation fuel using a vol-oxidizer with an oxygen concentration controller and sensor. We compared the characteristics of a galvanic sensor with a zirconium oxide (ZrO{sub 2}) one. The simulation fuel was manufactured with 14 metallic oxides, and used at a mass of 500 g HM/batch. At 500 deg. C, the galvanic and zirconium oxide sensors measured the oxidation time for the simulation fuel. Also, the oxidation time of the simulation fuel was measured according to a change of the oxygen concentration with the selected sensor, and the sample was analyzed. (authors)

  6. Wideband dichroic-filter design for LED-phosphor beam-combining

    DOE Patents [OSTI]

    Falicoff, Waqidi

    2010-12-28

    A general method is disclosed of designing two-component dichroic short-pass filters operable for incidence angle distributions over the 0-30.degree. range, and specific preferred embodiments are listed. The method is based on computer optimization algorithms for an N-layer design, specifically the N-dimensional conjugate-gradient minimization of a merit function based on difference from a target transmission spectrum, as well as subsequent cycles of needle synthesis for increasing N. A key feature of the method is the initial filter design, upon which the algorithm proceeds to iterate successive design candidates with smaller merit functions. This initial design, with high-index material H and low-index L, is (0.75 H, 0.5 L, 0.75 H)^m, denoting m (20-30) repetitions of a three-layer motif, giving rise to a filter with N=2 m+1.

  7. Multiphoton- and simultaneous conjugate Ramsey-Borde atom interferometers

    SciTech Connect (OSTI)

    Mueller, Holger; Chiow, Sheng-wey; Herrmann, Sven [Physics Department, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305 (United States); Chu, Steven [Physics Department, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305 (United States); Lawrence Berkeley National Laboratory and Department of Physics, University of California, Berkeley, 1 Cyclotron Road, Berkeley, CA 94720 (United States)

    2008-03-06

    We report on our experiment to measure h/M, the ratio of the Planck constant to the mass of Cs atoms, and thereby the fine-structure constant. The target accuracy is 1 part per billion or better. We focus on two recent milestones: (i) The first realization of atom interferometers based on light-pulse beam splitters that transfer the momentum of up to 12 photon pairs, which increases the useful signal (matter wave phase shift) by a factor of 144 compared to the beam splitters used in the best present atom interferometers. Moreover, they lead to a cancellation of important systematic effects. (ii) The first realization of a simultaneous pair of conjugate Ramsey-Borde interferometers. In these, the relative sign of the inertial term is reversed so that it can be cancelled. Simultaneous operation means that this holds for a time-dependent inertial term (vibrations) too, which promises a substantial improvement in the signal to noise ratio.

  8. Revised Manuscript

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

    5 October 2014 Energy Levels of Light Nuclei A = 5 D.R. Tilley a,b , C.M. Cheves a,c , J.L. Godwin a,c , G.M. Hale d , H.M. Hofmann e , J.H. Kelley a,b , C.G. Sheu a,c and H.R. Weller a,c a Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 b Department of Physics, North Carolina State University, Raleigh, NC 27695-8202 c Department of Physics, Duke University, Durham, NC 27708-0305 d Los Alamos National Laboratory, Los Alamos, NM 87545 e Universit¨ at Erlangen-N¨ urnberg,

  9. Conceptual design study on very small long-life gas cooled fast reactor using metallic natural Uranium-Zr as fuel cycle input

    SciTech Connect (OSTI)

    Monado, Fiber; Ariani, Menik; Su'ud, Zaki; Waris, Abdul; Basar, Khairul; Permana, Sidik; Aziz, Ferhat; Sekimoto, Hiroshi

    2014-02-12

    A conceptual design study of very small 350 MWth Gas-cooled Fast Reactors with Helium coolant has been performed. In this study Modified CANDLE burn-up scheme was implemented to create small and long life fast reactors with natural Uranium as fuel cycle input. Such system can utilize natural Uranium resources efficiently without the necessity of enrichment plant or reprocessing plant. The core with metallic fuel based was subdivided into 10 regions with the same volume. The fresh Natural Uranium is initially put in region-1, after one cycle of 10 years of burn-up it is shifted to region-2 and the each region-1 is filled by fresh Natural Uranium fuel. This concept is basically applied to all axial regions. The reactor discharge burn-up is 31.8% HM. From the neutronic point of view, this design is in compliance with good performance.

  10. The manufacture and performance of homogeneous microstructure SBR MOX fuel

    SciTech Connect (OSTI)

    Barker, Matthew A.; Stephenson, Keith; Weston, Rebecca

    2007-07-01

    In the early 1980's, British experience in the manufacture of mixed-oxide fast reactor fuel was used to develop a new thermal MOX manufacturing route called the Short Binder-less Route (SBR). Laboratory- scale development led to the manufacture of commercial PWR fuel in a small pilot plant, and the construction of the full-scale dual-line Sellafield MOX Plant (SMP). SMP's first MOX assemblies are now under irradiation. SBR MOX is manufactured with 100% co-milled feedstock, leading to a microstructure dominated by a solid solution of (U,Pu)O{sub 2} at the nominal enrichment. A comprehensive fuel performance research programme has demonstrated the benign performance of SBR MOX up to 54 MWd/kgHM. In particular, the homogeneous microstructure is believed to be instrumental in the favourable fission gas retention and PCI resistance properties. (authors)

  11. CRITICAL STAR FORMATION RATES FOR REIONIZATION: FULL REIONIZATION OCCURS AT REDSHIFT z Almost-Equal-To 7

    SciTech Connect (OSTI)

    Michael Shull, J.; Harness, Anthony; Trenti, Michele; Smith, Britton D. E-mail: trenti@colorado.edu E-mail: smit1685@msu.edu

    2012-03-10

    We assess the probable redshift (z{sub rei} Almost-Equal-To 7) for full reionization of the intergalactic medium (IGM) using a prescription for the comoving star formation rate (SFR) density ({rho}-dot{sub SFR}) required to maintain photoionization against recombination. Our newly developed online reionization simulator allows users to assess the required SFR and ionization histories, using a variety of assumptions for galactic and stellar populations, IGM clumping factor and temperature, and Lyman continuum (LyC) escape fraction. The decline in high-redshift galaxy candidates and Ly{alpha} emitters at z = 6-8 suggests a rising neutral fraction, with reionization at z {approx}> 7 increasingly difficult owing to increased recombination rates and constraints from the ionizing background and LyC mean free path. The required rate is {rho}-dot{sub SFR}{approx}(.018 M{sub sun}yr{sup -1}Mpc{sup -3})[(1+z)/8]{sup 3}(C{sub H}/3)(0.2/f{sub esc})T{sub 4}{sup -0.845} scaled to fiducial values of clumping factor C{sub H} = 3, escape fraction f{sub esc} = 0.2, electron temperature T{sub e} = 10{sup 4} K, and low-metallicity initial mass functions (IMFs) and stellar atmospheres. Our hydrodynamical + N-body simulations find a mean clumping factor C{sub H} Almost-Equal-To (2.9)[(1 + z)/6]{sup -1.1} in the photoionized, photoheated filaments at z = 5-9. The critical SFR could be reduced by increasing the minimum stellar mass, invoking a top-heavy IMF, or systematically increasing f{sub esc} at high z. The cosmic microwave background optical depth, {tau}{sub e} = 0.088 {+-} 0.015, could be explained by full reionization, producing {tau}{sub e} = 0.050 back to z{sub rei} Almost-Equal-To 7, augmented by {Delta}{tau}{sub e} Almost-Equal-To 0.01-0.04 in a partially ionized IGM at z > 7. In this scenario, the strongest 21 cm signal should occur at redshifted frequencies 124-167 MHz owing to IGM heating over an interval {Delta}z Almost-Equal-To 3 in the range z Almost-Equal-To 7.5-10.5.

  12. COSMIC ORIGINS SPECTROGRAPH OBSERVATIONS OF WARM INTERVENING GAS AT z {approx} 0.325 TOWARD 3C 263

    SciTech Connect (OSTI)

    Narayanan, Anand [Indian Institute of Space Science and Technology, Thiruvananthapuram 695547, Kerala (India); Savage, Blair D.; Wakker, Bart P., E-mail: anand@iist.ac.in, E-mail: savage@astro.wisc.edu, E-mail: wakker@astro.wisc.edu [Department of Astronomy, University of Wisconsin-Madison, 5534 Sterling Hall, 475 N. Charter Street, Madison, WI 53706-1582 (United States)

    2012-06-10

    We present HST/COS high-S/N observations of the z = 0.32566 multiphase absorber toward 3C 263. The Cosmic Origins Spectrograph (COS) data show absorption from H I (Ly{alpha} to Ly{theta}), O VI, C III, N III, Si III, and C II. The Ne VIII in this absorber is detected in the FUSE spectrum along with O III, O IV, and N IV. The low and intermediate ions are kinematically aligned with each other and H I and display narrow line widths of b {approx} 6-8 km s{sup -1}. The O VI {lambda}{lambda}1031, 1037 lines are kinematically offset by {Delta}v {approx} 12 km s{sup -1} from the low ions and are a factor of {approx}4 broader. All metal ions except O VI and Ne VIII are consistent with an origin in gas photoionized by the extragalactic background radiation. The bulk of the observed H I is also traced by this photoionized medium. The metallicity in this gas phase is Z {approx}> 0.15 Z{sub Sun} with carbon having near-solar abundances. The O VI and Ne VIII favor an origin in collisionally ionized gas at T = 5.2 Multiplication-Sign 10{sup 5} K. The H I absorption associated with this warm absorber is a broad-Ly{alpha} absorber (BLA) marginally detected in the COS spectrum. This warm gas phase has a metallicity of [X/H] {approx}-0.12 dex, and a total hydrogen column density of N( H) {approx} 3 Multiplication-Sign 10{sup 19} cm{sup -2}, which is {approx}2 dex higher than what is traced by the photoionized gas. Simultaneous detection of O VI, Ne VIII, and BLAs in an absorber can be a strong diagnostic of gas with T {approx} 10{sup 5}-10{sup 6} K corresponding to the warm phase of the warm-hot intergalactic medium or shock-heated gas in the extended halos of galaxies.

  13. THE FAR-ULTRAVIOLET 'CONTINUUM' IN PROTOPLANETARY DISK SYSTEMS. II. CARBON MONOXIDE FOURTH POSITIVE EMISSION AND ABSORPTION

    SciTech Connect (OSTI)

    France, Kevin; Schindhelm, Eric; Burgh, Eric B.; Brown, Alexander; Green, James C.; Herczeg, Gregory J.; Brown, Joanna M.; Harper, Graham M.; Linsky, Jeffrey L.; Yang Hao; Abgrall, Herve; Ardila, David R.; Bergin, Edwin; Bethell, Thomas; Calvet, Nuria; Ingleby, Laura; Espaillat, Catherine; Gregory, Scott G.; Hillenbrand, Lynne A.; Hussain, Gaitee

    2011-06-10

    We exploit the high sensitivity and moderate spectral resolution of the Hubble Space Telescope Cosmic Origins Spectrograph to detect far-ultraviolet (UV) spectral features of carbon monoxide (CO) present in the inner regions of protoplanetary disks for the first time. We present spectra of the classical T Tauri stars HN Tau, RECX-11, and V4046 Sgr, representative of a range of CO radiative processes. HN Tau shows CO bands in absorption against the accretion continuum. The CO absorption most likely arises in warm inner disk gas. We measure a CO column density and rotational excitation temperature of N(CO) = (2 {+-} 1) x 10{sup 17} cm{sup -2} and T{sub rot}(CO) 500 {+-} 200 K for the absorbing gas. We also detect CO A-X band emission in RECX-11 and V4046 Sgr, excited by UV line photons, predominantly H I Ly{alpha}. All three objects show emission from CO bands at {lambda} > 1560 A, which may be excited by a combination of UV photons and collisions with non-thermal electrons. In previous observations these emission processes were not accounted for due to blending with emission from the accretion shock, collisionally excited H{sub 2}, and photo-excited H{sub 2}, all of which appeared as a 'continuum' whose components could not be separated. The CO emission spectrum is strongly dependent upon the shape of the incident stellar Ly{alpha} emission profile. We find CO parameters in the range: N(CO) {approx} 10{sup 18}-10{sup 19} cm{sup -2}, T{sub rot}(CO) {approx}> 300 K for the Ly{alpha}-pumped emission. We combine these results with recent work on photo-excited and collisionally excited H{sub 2} emission, concluding that the observations of UV-emitting CO and H{sub 2} are consistent with a common spatial origin. We suggest that the CO/H{sub 2} ratio ({identical_to} N(CO)/N(H{sub 2})) in the inner disk is {approx}1, a transition between the much lower interstellar value and the higher value observed in solar system comets today, a result that will require future observational and theoretical study to confirm.

  14. Improved DC Gun Insulator Assembly

    SciTech Connect (OSTI)

    Sah, R.; Dudas, A.; Neubauer, M. L.; Poelker, M.; Surles-Law, K. E.L.

    2010-05-23

    Many user facilities such as synchrotron radiation light sources and free electron lasers require accelerating structures that support electric fields of 10-100 MV/m, especially at the start of the accelerator chain where ceramic insulators are used for very high gradient DC guns. These insulators are difficult to manufacture, require long commissioning times, and often exhibit poor reliability. Two technical approaches to solving this problem will be investigated. Firstly, inverted ceramics offer solutions for reduced gradients between the electrodes and ground. An inverted design will be presented for 350 kV, with maximum gradients in the range of 5-10 MV/m. Secondly, novel ceramic manufacturing processes will be studied, in order to protect triple junction locations from emission, by applying a coating with a bulk resistivity. The processes for creating this coating will be optimized to provide protection as well as be used to coat a ceramic with an appropriate gradient in bulk resistivity from the vacuum side to the air side of an HV standoff ceramic cylinder. Example insulator designs are being computer modelled, and insulator samples are being manufactured and tested

  15. Assessment of transition fuel cycle performance with and without a modified-open fuel cycle

    SciTech Connect (OSTI)

    Feng, B.; Kim, T. K.; Taiwo, T. A.

    2012-07-01

    The impacts of a modified-open fuel cycle (MOC) option as a transition step from the current once-through cycle (OTC) to a full-recycle fuel cycle (FRC) were assessed using the nuclear systems analysis code DANESS. The MOC of interest for this study was mono-recycling of plutonium in light water reactors (LWR-MOX). Two fuel cycle scenarios were evaluated with and without the MOC option: a 2-stage scenario with a direct path from the current fleet to the final FRC, and a 3-stage scenario with the MOC option as a transition step. The FRC reactor (fast reactor) was assumed to deploy in 2050 for both scenarios, and the MOC reactor in the 3-stage scenario was assumed to deploy in 2025. The last LWRs (using either UOX or MOX fuels) come online in 2050 and are decommissioned by 2110. Thus, the FRC is achieved after 2110. The reprocessing facilities were assumed to be available 2 years prior to the deployment of the MOC and FRC reactors with maximum reprocessing capacities of 2000 tHM/yr and 500 tHM/t for LWR-UOX and LWR-MOX used nuclear fuels (UNFs), respectively. Under a 1% nuclear energy demand growth assumption, both scenarios were able to sustain a full transition to the FRC without delay. For the 3-stage scenario, the share of LWR-MOX reactors reaches a peak of 15% of installed capacity, which resulted in 10% lower cumulative uranium consumption and SWU requirements compared to the 2-stage scenario during the transition period. The peak UNF storage requirement decreases by 50% in the 3-stage scenario, largely due to the earlier deployment of the reprocessing plants to support the MOC fuel cycle. (authors)

  16. Transmutation Analysis of Enriched Uranium and Deep Burn High Temperature Reactors

    SciTech Connect (OSTI)

    Michael A. Pope

    2012-07-01

    High temperature reactors (HTRs) have been under consideration for production of electricity, process heat, and for destruction of transuranics for decades. As part of the transmutation analysis efforts within the Fuel Cycle Research and Development (FCR&D) campaign, a need was identified for detailed discharge isotopics from HTRs for use in the VISION code. A conventional HTR using enriched uranium in UCO fuel was modeled having discharge burnup of 120 GWd/MTiHM. Also, a deep burn HTR (DB-HTR) was modeled burning transuranic (TRU)-only TRU-O2 fuel to a discharge burnup of 648 GWd/MTiHM. For each of these cases, unit cell depletion calculations were performed with SCALE/TRITON. Unit cells were used to perform this analysis using SCALE 6.1. Because of the long mean free paths (and migration lengths) of neutrons in HTRs, using a unit cell to represent a whole core can be non-trivial. The sizes of these cells were first set by using Serpent calculations to match a spectral index between unit cell and whole core domains. In the case of the DB-HTR, the unit cell which was arrived at in this way conserved the ratio of fuel to moderator found in a single block of fuel. In the conventional HTR case, a larger moderator-to-fuel ratio than that of a single block was needed to simulate the whole core spectrum. Discharge isotopics (for 500 nuclides) and one-group cross-sections (for 1022 nuclides) were delivered to the transmutation analysis team. This report provides documentation for these calculations. In addition to the discharge isotopics, one-group cross-sections were provided for the full list of 1022 nuclides tracked in the transmutation library.

  17. Tropical Africa: Land use, biomass, and carbon estimates for 1980

    SciTech Connect (OSTI)

    Brown, S.; Gaston, G.; Daniels, R.C.

    1996-06-01

    This document describes the contents of a digital database containing maximum potential aboveground biomass, land use, and estimated biomass and carbon data for 1980 and describes a methodology that may be used to extend this data set to 1990 and beyond based on population and land cover data. The biomass data and carbon estimates are for woody vegetation in Tropical Africa. These data were collected to reduce the uncertainty associated with the possible magnitude of historical releases of carbon from land use change. Tropical Africa is defined here as encompassing 22.7 x 10{sup 6} km{sup 2} of the earth`s land surface and includes those countries that for the most part are located in Tropical Africa. Countries bordering the Mediterranean Sea and in southern Africa (i.e., Egypt, Libya, Tunisia, Algeria, Morocco, South Africa, Lesotho, Swaziland, and Western Sahara) have maximum potential biomass and land cover information but do not have biomass or carbon estimate. The database was developed using the GRID module in the ARC/INFO{sup TM} geographic information system. Source data were obtained from the Food and Agriculture Organization (FAO), the U.S. National Geophysical Data Center, and a limited number of biomass-carbon density case studies. These data were used to derive the maximum potential and actual (ca. 1980) aboveground biomass-carbon values at regional and country levels. The land-use data provided were derived from a vegetation map originally produced for the FAO by the International Institute of Vegetation Mapping, Toulouse, France.

  18. Illicit Trafficking of Natural Radionuclides

    SciTech Connect (OSTI)

    Friedrich, Steinhaeusler; Lyudmila, Zaitseva

    2008-08-07

    Natural radionuclides have been subject to trafficking worldwide, involving natural uranium ore (U 238), processed uranium (yellow cake), low enriched uranium (<20% U 235) or highly enriched uranium (>20% U 235), radium (Ra 226), polonium (Po 210), and natural thorium ore (Th 232). An important prerequisite to successful illicit trafficking activities is access to a suitable logistical infrastructure enabling an undercover shipment of radioactive materials and, in case of trafficking natural uranium or thorium ore, capable of transporting large volumes of material. Covert en route diversion of an authorised uranium transport, together with covert diversion of uranium concentrate from an operating or closed uranium mines or mills, are subject of case studies. Such cases, involving Israel, Iran, Pakistan and Libya, have been analyzed in terms of international actors involved and methods deployed. Using international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (DSTO) and international experience gained from the fight against drug trafficking, a generic Trafficking Pathway Model (TPM) is developed for trafficking of natural radionuclides. The TPM covers the complete trafficking cycle, ranging from material diversion, covert material transport, material concealment, and all associated operational procedures. The model subdivides the trafficking cycle into five phases: (1) Material diversion by insider(s) or initiation by outsider(s); (2) Covert transport; (3) Material brokerage; (4) Material sale; (5) Material delivery. An Action Plan is recommended, addressing the strengthening of the national infrastructure for material protection and accounting, development of higher standards of good governance, and needs for improving the control system deployed by customs, border guards and security forces.

  19. THE CIRCUMGALACTIC MEDIUM OF MASSIVE GALAXIES AT z {approx} 3: A TEST FOR STELLAR FEEDBACK, GALACTIC OUTFLOWS, AND COLD STREAMS

    SciTech Connect (OSTI)

    Shen Sijing; Madau, Piero; Prochaska, J. Xavier [Department of Astronomy and Astrophysics, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States); Guedes, Javiera [Institute for Astronomy, ETH Zurich, Wolgang-Pauli-Strasse 27, CH-8093 Zurich (Switzerland); Mayer, Lucio [Institute of Theoretical Physics, University of Zurich, Winterthurerstrasse 190, CH-9057 Zurich (Switzerland); Wadsley, James [Department of Physics and Astronomy, McMaster University, Hamilton, ON L8S 4M1 (Canada)

    2013-03-10

    We present new results on the kinematics, thermal and ionization state, and spatial distribution of metal-enriched gas in the circumgalactic medium (CGM) of massive galaxies at redshift {approx}3, using the Eris suite of cosmological hydrodynamic ''zoom-in'' simulations. The reference run adopts a blastwave scheme for supernova feedback that produces large-scale galactic outflows, a star formation recipe based on a high gas density threshold, metal-dependent radiative cooling, and a model for the diffusion of metals and thermal energy. The effect of the local UV radiation field is added in post-processing. The CGM (defined as all gas at R > 0.2 R{sub vir} = 10 kpc, where R{sub vir} is the virial radius) contains multiple phases having a wide range of physical conditions, with more than half of its heavy elements locked in a warm-hot component at T > 10{sup 5} K. Synthetic spectra, generated by drawing sightlines through the CGM, produce interstellar absorption-line strengths of Ly{alpha}, C II, C IV, Si II, and Si IV as a function of the galactocentric impact parameter (scaled to the virial radius) that are in broad agreement with those observed at high redshift by Steidel et al. The covering factor of absorbing material declines less rapidly with impact parameter for Ly{alpha} and C IV compared to C II, Si IV, and Si II, with Ly{alpha} remaining strong (W{sub Ly{alpha}} > 300 mA) to {approx}> 5 R{sub vir} = 250 kpc. Only about one third of all the gas within R{sub vir} is outflowing. The fraction of sightlines within one virial radius that intercept optically thick, N{sub H{sub I}}>10{sup 17.2} cm{sup -2} material is 27%, in agreement with recent observations by Rudie et al. Such optically thick absorption is shown to trace inflowing ''cold'' streams that penetrate deep inside the virial radius. The streams, enriched to metallicities above 0.01 solar by previous episodes of star formation in the main host and in nearby dwarfs, are the origin of strong (N{sub C{sub II}}>10{sup 13} cm{sup -2}) C II absorption with a covering factor of 22% within R{sub vir} and 10% within 2 R{sub vir}. Galactic outflows do not cause any substantial suppression of the cold accretion mode. The central galaxy is surrounded by a large O VI halo, with a typical column density N{sub O{sub VI}} {approx}> 10{sup 14} cm{sup -2} and a near unity covering factor maintained all the way out to 150 kpc. This matches the trends recently observed in star-forming galaxies at low redshift by Tumlinson et al. Our zoom-in simulations of this single system appear then to reproduce quantitatively the complex baryonic processes that determine the exchange of matter, energy, and metals between galaxies and their surroundings.

  20. A=6Li (59AJ76)

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

    59AJ76) (See the Energy Level Diagram for 6Li) GENERAL: See also Table 6.2 [Table of Energy Levels] (in PDF or PS). Theory: See (MO54F, AD55, AU55, BA55S, IR55, LA55, OT55, FE56, ME56, NE56D, FR57, LE57F, LY57, SO57, TA57, PI58, SK58). 1. (a) 3H(3He, d)4He Qm = 14.319 Eb = 15.790 (b) 3H(3He, p)5He Qm = 11.136 (c) 3H(3He, p)4He + n Qm = 12.093 The relative intensities (43 ± 2, 6 ± 2, 51 ± 2) of reactions (a), (b) and (c), do not vary for E(3He) = 225 to 600 keV. The deuterons are isotropic

  1. Research News July 2015, Issue 10

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

    Alloy Raises the Bar for High-Temperature Performance page 3 the ENERGY lab NATIONAL ENERGY TECHNOLOGY LABORATORY From NETL's Office of Research & Development Researchnews July 2015, Issue 10 FE AT U RE ST O RY : A ll o y R a is e s th e B a r fo r H ig h -T e m p e ra F ro m N E T L' s O ff ic e o f R e s e a rc h & D e v e lo p m e n t R e s e a r c h n e w s Ju ly 20 15 , Is su e 10 Contents July 2015, Issue 10 2 Editorial: NETL's Educational Programs 3 Feature Story: Alloy Raises the

  2. untitled

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

    petrol Witnessing a birth WINTER 2008 S A N D I A T E C H N O L O G Y A Q UA RT E R LY R E S E A R C H & D E V E LO P M E N T MAG A Z I N E - VO LUM E 9 , N O. 4 Sunshine to petrol Beauty, molecules deep A l l i a n c e s > Sandia Technology (ISSN: 1547-5190) is a quarterly maga- zine published by Sandia National Laboratories. Sandia is a multiprogram engineering and science laboratory operated by Sandia Corporation, a Lockheed Martin company, for the U.S. Department of Energy. With main

  3. Cyber Wars Have SQUIDs, Will Travel A Trip to Nuclear North Korea

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

    lo s a l a m o s s c i e n c e a n d t e c h n o lo g y m ag a z i n e JUly 20 09 Wired for the Future Cyber Wars Have SQUIDs, Will Travel A Trip to Nuclear North Korea 1 663 lo s a l a m o s s c i e n c e a n d t e c h n o lo g y m ag a z i n e J U ly 2 0 0 9 During the Manhattan Project, Enrico Fermi, Nobel Laureate and leader of F-Division, meets with San Ildefonso Pueblo's Maria Martinez, famous worldwide for her extraordinary black pottery. features from terry wallace PrINcIPaL aSSocIatE

  4. EVIDENCE FOR A WEAK WIND FROM THE YOUNG SUN

    SciTech Connect (OSTI)

    Wood, Brian E.; Mller, Hans-Reinhard; Redfield, Seth; Edelman, Eric

    2014-02-01

    The early history of the solar wind has remained largely a mystery due to the difficulty of detecting winds around young stars that can serve as analogs for the young Sun. Here we report on the detection of a wind from the 500Myr old solar analog ?{sup 1} UMa (G1.5V), using spectroscopic observations from the Hubble Space Telescope. We detect H I Ly? absorption from the interaction region between the stellar wind and interstellar medium, i.e., the stellar astrosphere. With the assistance of hydrodynamic models of the ?{sup 1} UMa astrosphere, we infer a wind only half as strong as the solar wind for this star. This suggests that the Sun and solar-like stars do not have particularly strong coronal winds in their youth.

  5. Inelastic X-ray Scattering from Shocked Liquid Deuterium

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

    Regan, S. P.; Falk, K.; Gregori, G.; Radha, P. B.; Hu, S. X.; Boehly, T. R.; Crowley, B.; Glenzer, S. H.; Landen, O.; Gericke, D. O.; et al

    2012-12-28

    The Fermi-degenerate plasma conditions created in liquid deuterium by a laser-ablation—driven shock wave were probed with noncollective, spectrally resolved, inelastic x-ray Thomson scattering employing Cl Lyα line emission at 2.96 keV. Thus, these first x-ray Thomson scattering measurements of the microscopic properties of shocked deuterium show an inferred spatially averaged electron temperature of 8±5 eV, an electron density of 2.2(±0.5)×1023 cm-3, and an ionization of 0.8 (-0.25, +0.15). Our two-dimensional hydrodynamic simulations using equation-of-state models suited for the extreme parameters occurring in inertial confinement fusion research and planetary interiors are consistent with the experimental results.

  6. I I LI I L I

    Office of Legacy Management (LM)

    LI - I L I 1 II C c - ORNL/RASA-9618 OAK RlDGE NATlONAl. LA8ORATORY Results of the Independent Radiological Verification Survey at B&T Metals, 425 West Town Street, Columbus, Ohio (cooolv) M . E. Murray V. P. Patania C. A. Johnson M N M E D *wD OPEbM~ B V WUCNEEDllW?ME IWiARCH CoRpoRAng FoRTHEwITf@%tATeB ltEpAAMwTmBMeR(Ly ORNL-27 (34el ~~- L._~ This report has been reproduced directly from the best available copy. Avaiiable to DOE and DOE contractors from the Office of Scientific and

  7. INTERIOR

    Office of Legacy Management (LM)

    c m y 7 INTERIOR Seismic monitoring o f t h e RULISON underground L nuclear e x p l o s i o n near R i f l e , Colorado, on 10 September lyGg by R. M. Hamilton, B. E. Smith and J. H. Healy Own-File R e w r t 1970 This r e p r t i s prelircinary and has n o t been e d i t e d o r reviewed f o r conformity w i t h G e o l o g i c a l Survey standards and n o r e n c l a t u r e . RETURN T O NV TECHNICAL LIBRARY DISCLAIMER Portions of this document may be illegible in electronic image products.

  8. Neutral particle beam sensing and steering

    DOE Patents [OSTI]

    Maier, II, William B. (Los Alamos, NM); Cobb, Donald D. (Los Alamos, NM); Robiscoe, Richard T. (Los Alamos, NM)

    1991-01-01

    The direction of a neutral particle beam (NPB) is determined by detecting Ly.alpha. radiation emitted during motional quenching of excited H(2S) atoms in the beam during movement of the atoms through a magnetic field. At least one detector is placed adjacent the beam exit to define an optical axis that intercepts the beam at a viewing angle to include a volume generating a selected number of photons for detection. The detection system includes a lens having an area that is small relative to the NPB area and a pixel array located in the focal plane of the lens. The lens viewing angle and area pixel array are selected to optimize the beam tilt sensitivity. In one embodiment, two detectors are placed coplanar with the beam axis to generate a difference signal that is insensitive to beam variations other than beam tilt.

  9. Laser heating of solid matter by light pressure-driven shocks

    SciTech Connect (OSTI)

    Akli, K; Hansen, S B; Kemp, A J; Freeman, R R; Beg, F N; Clark, D; Chen, S; Hey, D; Highbarger, K; Giraldez, E; Green, J; Gregori, G; Lancaster, K; Ma, T; MacKinnon, A J; Norreys, P A; Patel, N; Patel, P; Shearer, C; Stephens, R B; Stoeckl, C; Storm, M; Theobald, W; Van Woerkom, L; Weber, R; Key, M H

    2007-05-04

    Heating by irradiation of a solid surface in vacuum with 5 x 10{sup 20} W cm{sup -2}, 0.8 ps, 1.05 {micro}m wavelength laser light is studied by x-ray spectroscopy of the K-shell emission from thin layers of Ni, Mo and V. A surface layer is heated to {approx} 5 keV with an axial temperature gradient of 0.6 {micro}m scale length. Images of Ni Ly{sub {alpha}} show the hot region has a {approx} 25 {micro}m diameter, much smaller than {approx} 70 {micro}m region of K{sub {alpha}} emission. 2D particle-in-cell (PIC) simulations suggest that the surface heating is due to a light pressure driven shock.

  10. Flim3.l Elaenbud

    Office of Legacy Management (LM)

    Fe 66 i.. y, N&i) -, mc . _ Flim3.l Elaenbud w. B. Ra* ' PBBDBm $ToIB SlllJBoLI 3!3HtwR3thaah ,- ". i ti?-,J~ -; Awvt 3% 1951 on hg?mt mlh, a visit Ma zsRcb to t&m ?!bylmd cha cQulpa?zy T&en3 Mnotfte r;au%s am proce88ed for the 8xtrac?tion of ru% sa2ar and lnuttle-gracie timrim ni*tratea. ?kywuod Chsrdcal Co. has been process- ~tharsmrtrrlalsforrpp~~ly50pacln~dbu&rcarjr~ 8t8xtiAl backgroMd in tlha haa.ing of tlLuhmbe8ring naataia&. mr this rn8oxl# it unb thopght aM8abls

  11. This

    Office of Legacy Management (LM)

    doc;nzWnt conslztr, of NO. fif 7 copies, Serieeb 3 1, i/ "0 Ihi/ 1 l . . . A &pm& I--' rltti 4-' aimoaf~m?k -0prrtiav Data: P F. Brown' 49 6 0 c ;i @v d _---- __ ,--_ ~-~ ..~.. __l_l ___ - - . . - . . --.", -~ ___-- -- _... - -.-.-- ' / L' / II. - ,sitied 4 (4 I &y . . --,~- e c Brd l * & "4 d t I w l mtlauo A&#ar8u8tfirrt,~~~ly5,~w,~~-' a$d 81th 6w ud m, 6n@--, -*Lllu *~~bla -lr mavlauualbo&lgn~~~tor8m~~88~~ &?aas-11. mda8ta~tlaof~llitiwf~fb,--

  12. Y H-S I-H HATIOHAL LEAth~~Y~~OF' OtUO ' Industrial Hygiene No.

    Office of Legacy Management (LM)

    H-S I-H HATIOHAL LEAth~~Y~~OF' OtUO ' Industrial Hygiene No. P.O. Box 158)At.' He&by~kation Sample Nos. ? Sk. 0 qq! Cinchnail 31;Obio Type of SampleCI" lz -- HEALTH AND SAFETY DIVISIQN Analyze for u Method &An.ly,i, ;i __ = - . -- Industrial Hygiene No. P.O. Box 158 Mt.~He&lly Qq99 Q' ' - Ciacian& 31. 01 Sample Nos. 992' I HtAL I H ANU SAFt H-S 1-H J MATI~ LEID-WAIJY. OF OIUO station rio Type of S&h d' r dQsr CYS ..- . . -.. ..- -. -- :TY DIVISICJN Analyze for d t I I I

  13. I

    Office of Legacy Management (LM)

    --&) /+' ) 3 -i/ ii!' M/k "3 . . * . ~T~&,TTSTT:~ .: -~53~~i!&i-:r~ 1: c r I * .I " / : , ; . . . 3. .i - w ~trial IIyi-;iene Orand Re&lh and safety Laboratmy Im,mdc Octokr 21, u% 2' ' - ' 1' !!T?H _ - .a r. ,...~.b,)i~XTia~ !I4%L, XYm 2. ..T* 2zdJ-- l ,,C 1 .rJh, !' 11., ;dv 2: ;" 11 I:r,t, :433kr 3- :r. L. r> .-. ? Ly-m-i, ! pm* j!., >- I I;- ,:r* : "y l hl~wt, li:.!l, iah pm ~iL.A.4 ;'A0 U.S. .' .LJf& Er++r;;;- LI3zL?.i !!w ' Lsriz Qcr&N.~~3

  14. Water vapor distribution in protoplanetary disks

    SciTech Connect (OSTI)

    Du, Fujun; Bergin, Edwin A.

    2014-09-01

    Water vapor has been detected in protoplanetary disks. In this work, we model the distribution of water vapor in protoplanetary disks with a thermo-chemical code. For a set of parameterized disk models, we calculate the distribution of dust temperature and radiation field of the disk with a Monte Carlo method, and then solve the gas temperature distribution and chemical composition. The radiative transfer includes detailed treatment of scattering by atomic hydrogen and absorption by water of Ly? photons, since the Ly? line dominates the UV spectrum of accreting young stars. In a fiducial model, we find that warm water vapor with temperature around 300 K is mainly distributed in a small and well-confined region in the inner disk. The inner boundary of the warm water region is where the shielding of UV field due to dust and water itself become significant. The outer boundary is where the dust temperature drops below the water condensation temperature. A more luminous central star leads to a more extended distribution of warm water vapor, while dust growth and settling tends to reduce the amount of warm water vapor. Based on typical assumptions regarding the elemental oxygen abundance and the water chemistry, the column density of warm water vapor can be as high as 10{sup 22} cm{sup 2}. A small amount of hot water vapor with temperature higher than ?300 K exists in a more extended region in the upper atmosphere of the disk. Cold water vapor with temperature lower than 100 K is distributed over the entire disk, produced by photodesorption of the water ice.

  15. HST/COS SPECTRA OF THREE QSOs THAT PROBE THE CIRCUMGALACTIC MEDIUM OF A SINGLE SPIRAL GALAXY: EVIDENCE FOR GAS RECYCLING AND OUTFLOW

    SciTech Connect (OSTI)

    Keeney, Brian A.; Stocke, John T.; Danforth, Charles W.; Shull, J. Michael; Green, James C. [Center for Astrophysics and Space Astronomy, Department of Astrophysical and Planetary Sciences, University of Colorado, 389 UCB, Boulder, CO 80309 (United States)] [Center for Astrophysics and Space Astronomy, Department of Astrophysical and Planetary Sciences, University of Colorado, 389 UCB, Boulder, CO 80309 (United States); Rosenberg, Jessica L. [Department of Physics and Astronomy, George Mason University, Fairfax, VA 22030 (United States)] [Department of Physics and Astronomy, George Mason University, Fairfax, VA 22030 (United States); Ryan-Weber, Emma V. [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Mail H30, P.O. Box 218, Hawthorn, 3122 VIC (Australia)] [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Mail H30, P.O. Box 218, Hawthorn, 3122 VIC (Australia); Savage, Blair D., E-mail: brian.keeney@colorado.edu [Department of Astronomy, University of Wisconsin-Madison, 5534 Sterling Hall, 475 North Charter Street, Madison, WI 53706 (United States)

    2013-03-01

    We have used the Cosmic Origins Spectrograph (COS) to obtain far-UV spectra of three closely spaced QSO sight lines that probe the circumgalactic medium (CGM) of an edge-on spiral galaxy, ESO 157-49, at impact parameters of 74 and 93 h {sup -1} {sub 70} kpc near its major axis and 172 h {sup -1} {sub 70} kpc along its minor axis. H I Ly{alpha} absorption is detected at the galaxy redshift in the spectra of all three QSOs, and metal lines of Si III, Si IV, and C IV are detected along the two major-axis sight lines. Photoionization models of these clouds suggest metallicities close to the galaxy metallicity, cloud sizes of {approx}1 kpc, and gas masses of {approx}10{sup 4} M {sub Sun }. Given the high covering factor of these clouds, ESO 157-49 could harbor {approx}2 Multiplication-Sign 10{sup 9} M {sub Sun} of warm CGM gas. We detect no metals in the sight line that probes the galaxy along its minor axis, but gas at the galaxy metallicity would not have detectable metal absorption with ionization conditions similar to the major-axis clouds. The kinematics of the major-axis clouds favor these being portions of a 'galactic fountain' of recycled gas, while two of the three minor-axis clouds are constrained geometrically to be outflowing gas. In addition, one of our QSO sight lines probes a second more distant spiral, ESO 157-50, along its major axis at an impact parameter of 88 h {sup -1} {sub 70} kpc. Strong H I Ly{alpha} and C IV absorption only are detected in the QSO spectrum at the redshift of ESO 157-50.

  16. THE He II POST-REIONIZATION EPOCH: HST/COS OBSERVATIONS OF THE QUASAR HS1700+6416

    SciTech Connect (OSTI)

    Syphers, David; Shull, J. Michael, E-mail: david.syphers@colorado.edu, E-mail: michael.shull@colorado.edu [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309 (United States)

    2013-03-10

    The reionization epoch of singly ionized helium (He II) is believed to start at redshifts z {approx} 3.5-4 and be nearly complete by z {approx_equal} 2.7. We explore the post-reionization epoch with far-ultraviolet spectra of the bright, high-redshift quasar HS1700+6416 taken by the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope, which show strong He II ({lambda}303.78) absorption shortward of the QSO redshift, z{sub QSO} = 2.75. We discuss these data as they probe the post-reionization history of He II and the local ionization environment around the quasar and transverse to the line of sight, finding that quasars are likely responsible for much of the ionization. We compare previous spectra taken by the Far-Ultraviolet Spectroscopic Explorer to the current COS data, which have a substantially higher signal-to-noise ratio. The Gunn-Peterson trough recovers at lower redshifts, with the effective optical depth falling from {tau}{sub eff} {approx_equal} 1.8 at z {approx} 2.7 to {tau}{sub eff} {approx_equal} 0.7 at z {approx} 2.3, higher than has been reported in earlier work. We see an interesting excess of flux near the He II Ly{alpha} break, which could be quasar line emission, although likely not He II Ly{alpha}. We present spectra of four possible transverse-proximity quasars, although the UV hardness data are not of sufficient quality to say if their effects are seen along the HS1700 sightline.

  17. Reconstitution of the cellular response to DNA damage in vitro using damage-activated extracts from mammalian cells

    SciTech Connect (OSTI)

    Roper, Katherine; Coverley, Dawn

    2012-03-10

    In proliferating mammalian cells, DNA damage is detected by sensors that elicit a cellular response which arrests the cell cycle and repairs the damage. As part of the DNA damage response, DNA replication is inhibited and, within seconds, histone H2AX is phosphorylated. Here we describe a cell-free system that reconstitutes the cellular response to DNA double strand breaks using damage-activated cell extracts and naieve nuclei. Using this system the effect of damage signalling on nuclei that do not contain DNA lesions can be studied, thereby uncoupling signalling and repair. Soluble extracts from G1/S phase cells that were treated with etoposide before isolation, or pre-incubated with nuclei from etoposide-treated cells during an in vitro activation reaction, restrain both initiation and elongation of DNA replication in naieve nuclei. At the same time, H2AX is phosphorylated in naieve nuclei in a manner that is dependent upon the phosphatidylinositol 3-kinase-like protein kinases. Notably, phosphorylated H2AX is not focal in naieve nuclei, but is evident throughout the nucleus suggesting that in the absence of DNA lesions the signal is not amplified such that discrete foci can be detected. This system offers a novel screening approach for inhibitors of DNA damage response kinases, which we demonstrate using the inhibitors wortmannin and LY294002. -- Highlights: Black-Right-Pointing-Pointer A cell free system that reconstitutes the response to DNA damage in the absence of DNA lesions. Black-Right-Pointing-Pointer Damage-activated extracts impose the cellular response to DNA damage on naieve nuclei. Black-Right-Pointing-Pointer PIKK-dependent response impacts positively and negatively on two separate fluorescent outputs. Black-Right-Pointing-Pointer Can be used to screen for inhibitors that impact on the response to damage but not on DNA repair. Black-Right-Pointing-Pointer LY294002 and wortmannin demonstrate the system's potential as a pathway focused screening approach.

  18. CHEMICAL DIFFERENCES BETWEEN SLUDGE SOLIDS AT THE F AND H AREA TANK FARMS

    SciTech Connect (OSTI)

    Reboul, S.

    2012-08-29

    The primary source of waste solids received into the F Area Tank Farm (FTF) was from PUREX processing performed to recover uranium and plutonium from irradiated depleted uranium targets. In contrast, two primary sources of waste solids were received into the H Area Tank Farm (HTF): a) waste from PUREX processing; and b) waste from H-modified (HM) processing performed to recover uranium and neptunium from burned enriched uranium fuel. Due to the differences between the irradiated depleted uranium targets and the burned enriched uranium fuel, the average compositions of the F and H Area wastes are markedly different from one another. Both F and H Area wastes contain significant amounts of iron and aluminum compounds. However, because the iron content of PUREX waste is higher than that of HM waste, and the aluminum content of PUREX waste is lower than that of HM waste, the iron to aluminum ratios of typical FTF waste solids are appreciably higher than those of typical HTF waste solids. Other constituents present at significantly higher concentrations in the typical FTF waste solids include uranium, nickel, ruthenium, zinc, silver, cobalt and copper. In contrast, constituents present at significantly higher concentrations in the typical HTF waste solids include mercury, thorium, oxalate, and radionuclides U-233, U-234, U-235, U-236, Pu-238, Pu-242, Cm-244, and Cm-245. Because of the higher concentrations of Pu-238 in HTF, the long-term concentrations of Th-230 and Ra-226 (from Pu-238 decay) will also be higher in HTF. The uranium and plutonium distributions of the average FTF waste were found to be consistent with depleted uranium and weapons grade plutonium, respectively (U-235 comprised 0.3 wt% of the FTF uranium, and Pu-240 comprised 6 wt% of the FTF plutonium). In contrast, at HTF, U-235 comprised 5 wt% of the uranium, and Pu-240 comprised 17 wt% of the plutonium, consistent with enriched uranium and high burn-up plutonium. X-ray diffraction analyses of various FTF and HTF samples indicated that the primary crystalline compounds of iron in sludge solids are Fe{sub 2}O{sub 3}, Fe{sub 3}O{sub 4}, and FeO(OH), and the primary crystalline compounds of aluminum are Al(OH){sub 3} and AlO(OH). Also identified were carbonate compounds of calcium, magnesium, and sodium; a nitrated sodium aluminosilicate; and various uranium compounds. Consistent with expectations, oxalate compounds were identified in solids associated with oxalic acid cleaning operations. The most likely oxidation states and chemical forms of technetium are assessed in the context of solubility, since technetium-99 is a key risk driver from an environmental fate and transport perspective. The primary oxidation state of technetium in SRS sludge solids is expected to be Tc(IV). In salt waste, the primary oxidation state is expected to be Tc(VII). The primary form of technetium in sludge is expected to be a hydrated technetium dioxide, TcO{sub 2} {center_dot} xH{sub 2}O, which is relatively insoluble and likely co-precipitated with iron. In salt waste solutions, the primary form of technetium is expected to be the very soluble pertechnetate anion, TcO{sub 4}{sup -}. The relative differences between the F and H Tank Farm waste provide a basis for anticipating differences that will occur as constituents of FTF and HTF waste residue enter the environment over the long-term future. If a constituent is significantly more dominant in one of the Tank Farms, its long-term environmental contribution will likely be commensurately higher, assuming the environmental transport conditions of the two Tank Farms share some commonality. It is in this vein that the information cited in this document is provided - for use during the generation, assessment, and validation of Performance Assessment modeling results.

  19. THE STELLAR-TO-HALO MASS RELATION OF LOCAL GALAXIES SEGREGATES BY COLOR

    SciTech Connect (OSTI)

    Rodrguez-Puebla, Aldo; Yang, Xiaohu; Foucaud, Sebastien; Jing, Y. P.; Avila-Reese, Vladimir; Drory, Niv

    2015-02-01

    By means of a statistical approach that combines different semi-empirical methods of galaxy-halo connection, we derive the stellar-to-halo mass relations (SHMR) of local blue and red central galaxies. We also constrain the fraction of halos hosting blue/red central galaxies and the occupation statistics of blue and red satellites as a function of halo mass, M {sub h}. For the observational input we use the blue and red central/satellite galaxy stellar mass functions and two-point correlation functions in the stellar mass range of 9 < log(M {sub *}/M {sub ?})<12. We find that: (1)the SHMR of central galaxies is segregated by color, with blue centrals having a SHMR above that of red centrals; at log(M {sub h}/M {sub ?}) ?12, the M {sub *}-to-M {sub h} ratio of the blue centrals is ?0.05, which is ?1.7times larger than the value of red centrals. (2) The constrained scatters around the SHMRs of red and blue centrals are ?0.14 and ?0.11dex, respectively. The scatter of the average SHMR of all central galaxies changes from ?0.20dex to ?0.14dex in the 11.3 < log(M {sub h}/M {sub ?})<15 range. (3) The fraction of halos hosting blue centrals at M{sub h}=10{sup 11} M {sub ?} is 87%, but at 2 10{sup 12} M {sub ?} decays to ?20%, approaching a few percent at higher masses. The characteristic mass at which this fraction is the same for blue and red galaxies is M{sub h}?710{sup 11} M {sub ?}. Our results suggest that the SHMR of central galaxies at large masses is shaped by mass quenching. At low masses processes that delay star formation without invoking too strong supernova-driven outflows could explain the high M {sub *}-to-M {sub h} ratios of blue centrals as compared to those of the scarce red centrals.

  20. The Russian Federation's Ministry of Atomic Energy: Programs and Developments

    SciTech Connect (OSTI)

    CM Johnson

    2000-07-24

    This paper reviews select programs driving the Ministry of Atomic Energy of the Russian Federation's (Minatom) efforts to raise funds, comments on their potential viability, and highlights areas likely to be of particular concern for the US over the next three to five years. The paper's findings are: (1) Despite numerous cabinet displacements throughout the Yeltsin administration, Yevgeny Adamov was reappointed Minister on four occasions. With Boris Yeltsin's January 1, 2000 resignation, Adamov's long-term position as the head of the Ministry is more tenuous, but he will likely retain his position until at least the March 2000 elections. Acting President Vladimir Putin is unlikely to reorganize his cabinet prior to that date and there are no signs that Putin is dissatisfied with Adamov's leadership of Minatom. (2) Adamov's chief priorities are downsizing Minatom's defense sector, increasing the oversight of subsidiary bodies by the central bureaucracy and consolidating commercial elements of the Ministry within an umbrella organization called Atomprom. (3) Viktor Mikhaylov, Adamov's predecessor and critic of his reform efforts, has been relieved of his duties as First Deputy Minister. While he retains his positions as Chief of the Science Councils and Chief Scientist at Arzamas-16, his influence on Minatom's direction is greatly diminished. Adamov will likely continue his efforts to further marginalize Mikhaylov in the coming year. (4) Securing extra-budgetary sources of income continues to be the major factor guiding Minatom's international business dealings. The Ministry will continue to aggressively promote the sale of nuclear technology abroad, often to countries with questionable nonproliferation commitments. (5) Given the financial difficulties in Russia and Minatom's client states, however, few nuclear development programs will come to fruition for a number of years, if ever. Nevertheless, certain peaceful nuclear cooperation agreements should be carefully monitored--particularly those negotiated with Cuba, Iran, Libya and Syria. (6) Waste management has also risen in importance for Minatom. Opportunities for raising funds by reprocessing, storing and permanently disposing of spent fuel from foreign states are being explored. Although currently prohibited by federal law, the Russian Parliament will likely pass legislation in support of this program.

  1. THE GREAT OBSERVATORIES ORIGINS DEEP SURVEY: CONSTRAINTS ON THE LYMAN CONTINUUM ESCAPE FRACTION DISTRIBUTION OF LYMAN-BREAK GALAXIES AT 3.4 < z < 4.5

    SciTech Connect (OSTI)

    Vanzella, E.; Nonino, M.; Fontanot, F.; Cristiani, S.; Tozzi, P.; Giavalisco, M.; Inoue, A. K.; Grazian, A.; Giallongo, E.; Boutsia, K.; Fontana, A.; Pentericci, L.; Dickinson, M.; Stern, D.; Ferguson, H.; Spinrad, H.; Rosati, P.

    2010-12-10

    We use ultra-deep ultraviolet VLT/VIMOS intermediate-band and VLT/FORS1 narrowband imaging in the GOODS Southern field to derive limits on the distribution of the escape fraction (f{sub esc}) of ionizing radiation for L {>=} L*{sub z=3} Lyman-break galaxies (LBGs) at redshift 3.4-4.5. Only one LBG, at redshift z = 3.795, is detected in its Lyman continuum (LyC; S/N {approx_equal} 5.5), the highest redshift galaxy currently known with a direct detection. Its ultraviolet morphology is quite compact (R{sub eff} = 0.8 kpc physical). Three out of seven active galactic nuclei are also detected in their LyC, including one at redshift z = 3.951 and z{sub 850} = 26.1. From stacked data (LBGs), we set an upper limit to the average f{sub esc} in the range 5%-20%, depending on how the data are selected (e.g., by magnitude and/or redshift). We undertake extensive Monte Carlo simulations that take into account intergalactic attenuation, stellar population synthesis models, dust extinction, and photometric noise in order to explore the moments of the distribution of the escaping radiation. Various distributions (exponential, log-normal, and Gaussian) are explored. We find that the median f{sub esc} is lower than {approx_equal}6% with an 84% percentile limit not larger than 20%. If this result remains valid for fainter LBGs down to current observational limits, then the LBG population might be not sufficient to account for the entire photoionization budget at the redshifts considered here, with the exact details dependent upon the assumed ionizing background and QSO contribution thereto. It is possible that f{sub esc} depends on the UV luminosity of the galaxies, with fainter galaxies having higher f{sub esc}, and estimates of f{sub esc} from a sample of faint LBGs from HUDF (i{sub 775} {<=}28.5) are in broad quantitative agreement with such a scenario.

  2. THE COLUMN DENSITY DISTRIBUTION AND CONTINUUM OPACITY OF THE INTERGALACTIC AND CIRCUMGALACTIC MEDIUM AT REDSHIFT (z) = 2.4

    SciTech Connect (OSTI)

    Rudie, Gwen C.; Steidel, Charles C. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, MS 249-17, Pasadena, CA 91125 (United States); Shapley, Alice E. [Department of Astronomy, University of California, Los Angeles, 430 Portola Plaza, Los Angeles, CA 90024 (United States); Pettini, Max, E-mail: gwen@astro.caltech.edu [Institute of Astronomy, Madingley Road, Cambridge CB3 0HA (United Kingdom)

    2013-06-01

    We present new high-precision measurements of the opacity of the intergalactic and circumgalactic medium (IGM; CGM) at (z) = 2.4. Using Voigt profile fits to the full Ly{alpha} and Ly{beta} forests in 15 high-resolution high-S/N spectra of hyperluminous QSOs, we make the first statistically robust measurement of the frequency of absorbers with H I column densities 14{approx}< log (N{sub H{sub I}}/cm{sup -2}){approx}<17.2. We also present the first measurements of the frequency distribution of H I absorbers in the volume surrounding high-z galaxies (the CGM, 300 pkpc), finding that the incidence of absorbers in the CGM is much higher than in the IGM. In agreement with Rudie et al., we find that there are fractionally more high-N{sub H{sub I}} absorbers than low-N{sub H{sub I}} absorbers in the CGM compared to the IGM, leading to a shallower power law fit to the CGM frequency distribution. We use these new measurements to calculate the total opacity of the IGM and CGM to hydrogen-ionizing photons, finding significantly higher opacity than most previous studies, especially from absorbers with log (N{sub H{sub I}}/cm{sup -2}) < 17.2. Reproducing the opacity measured in our data as well as the incidence of absorbers with log (N{sub H{sub I}}/cm{sup -2})>17.2 requires a broken power law parameterization of the frequency distribution with a break near N{sub H{sub I}} Almost-Equal-To 10{sup 15} cm{sup -2}. We compute new estimates of the mean free path ({lambda}{sub mfp}) to hydrogen-ionizing photons at z{sub em} = 2.4, finding {lambda}{sub mfp} = 147 {+-} 15 Mpc when considering only IGM opacity. If instead, we consider photons emanating from a high-z star-forming galaxy and account for the local excess opacity due to the surrounding CGM of the galaxy itself, the mean free path is reduced to {lambda}{sub mfp} = 121 {+-} 15 Mpc. These {lambda}{sub mfp} measurements are smaller than recent estimates and should inform future studies of the metagalactic UV background and of ionizing sources at z Almost-Equal-To 2-3.

  3. The BigBoss Experiment

    SciTech Connect (OSTI)

    Schelgel, D.; Abdalla, F.; Abraham, T.; Ahn, C.; Allende Prieto, C.; Annis, J.; Aubourg, E.; Azzaro, M.; Bailey, S.; Baltay, C.; Baugh, C.; Bebek, C.; Becerril, S.; Blanton, M.; Bolton, A.; Bromley, B.; Cahn, R.; Carton, P.-H.; Cervanted-Cota, J.L.; Chu, Y.; Cortes, M.; /APC, Paris /Brookhaven /IRFU, Saclay /Marseille, CPPM /Marseille, CPT /Durham U. / /IEU, Seoul /Fermilab /IAA, Granada /IAC, La Laguna / /IAC, Mexico / / /Madrid, IFT /Marseille, Lab. Astrophys. / / /New York U. /Valencia U.

    2012-06-07

    BigBOSS is a Stage IV ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with a wide-area galaxy and quasar redshift survey over 14,000 square degrees. It has been conditionally accepted by NOAO in response to a call for major new instrumentation and a high-impact science program for the 4-m Mayall telescope at Kitt Peak. The BigBOSS instrument is a robotically-actuated, fiber-fed spectrograph capable of taking 5000 simultaneous spectra over a wavelength range from 340 nm to 1060 nm, with a resolution R = {lambda}/{Delta}{lambda} = 3000-4800. Using data from imaging surveys that are already underway, spectroscopic targets are selected that trace the underlying dark matter distribution. In particular, targets include luminous red galaxies (LRGs) up to z = 1.0, extending the BOSS LRG survey in both redshift and survey area. To probe the universe out to even higher redshift, BigBOSS will target bright [OII] emission line galaxies (ELGs) up to z = 1.7. In total, 20 million galaxy redshifts are obtained to measure the BAO feature, trace the matter power spectrum at smaller scales, and detect redshift space distortions. BigBOSS will provide additional constraints on early dark energy and on the curvature of the universe by measuring the Ly-alpha forest in the spectra of over 600,000 2.2 < z < 3.5 quasars. BigBOSS galaxy BAO measurements combined with an analysis of the broadband power, including the Ly-alpha forest in BigBOSS quasar spectra, achieves a FOM of 395 with Planck plus Stage III priors. This FOM is based on conservative assumptions for the analysis of broad band power (k{sub max} = 0.15), and could grow to over 600 if current work allows us to push the analysis to higher wave numbers (k{sub max} = 0.3). BigBOSS will also place constraints on theories of modified gravity and inflation, and will measure the sum of neutrino masses to 0.024 eV accuracy.

  4. A HUBBLE SPACE TELESCOPE/COSMIC ORIGINS SPECTROGRAPH SEARCH FOR WARM-HOT BARYONS IN THE Mrk 421 SIGHT LINE

    SciTech Connect (OSTI)

    Danforth, Charles W.; Stocke, John T.; Keeney, Brian A.; Penton, Steven V.; Shull, J. Michael; Yao Yangsen; Green, James C., E-mail: danforth@colorado.edu [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, 389-UCB, Boulder, CO 80309 (United States)

    2011-12-10

    Thermally broadened Ly{alpha} absorbers (BLAs) offer an alternate method to using highly ionized metal absorbers (O VI, O VII, etc.) to probe the warm-hot intergalactic medium (WHIM, T = 10{sup 5}-10{sup 7} K). Until now, WHIM surveys via BLAs have been no less ambiguous than those via far-UV and X-ray metal-ion probes. Detecting these weak, broad features requires background sources with a well-characterized far-UV continuum and data of very high quality. However, a recent Hubble Space Telescope/Cosmic Origins Spectrograph (COS) observation of the z = 0.03 blazar Mrk 421 allows us to perform a metal-independent search for WHIM gas with unprecedented precision. The data have high signal-to-noise ratio (S/N Almost-Equal-To 50 per {approx}20 km s{sup -1} resolution element) and the smooth, power-law blazar spectrum allows a fully parametric continuum model. We analyze the Mrk 421 sight line for BLA absorbers, particularly for counterparts to the proposed O VII WHIM systems reported by Nicastro et al. based on Chandra/Low Energy Transmission Grating observations. We derive the Ly{alpha} profiles predicted by the X-ray observations. The S/N of the COS data is high (S/N Almost-Equal-To 25 pixel{sup -1}), but much higher S/N can be obtained by binning the data to widths characteristic of the expected BLA profiles. With this technique, we are sensitive to WHIM gas over a large (N{sub H}, T) parameter range in the Mrk 421 sight line. We rule out the claimed Nicastro et al. O VII detections at their nominal temperatures (T {approx} 1-2 Multiplication-Sign 10{sup 6} K) and metallicities (Z = 0.1 Z{sub Sun }) at {approx}> 2{sigma} level. However, WHIM gas at higher temperatures and/or higher metallicities is consistent with our COS non-detections.

  5. An HST COS 'SNAPSHOT' spectrum of the K supergiant ? Vel (K4Ib-II)

    SciTech Connect (OSTI)

    Carpenter, Kenneth G. [NASA/GSFC Code 667, Greenbelt, MD 20771 (United States); Ayres, Thomas R. [University of Colorado, CASA, 389-UCB, Boulder, CO 80309 (United States); Harper, Graham M. [School of Physics, Trinity College, Dublin 2 (Ireland); Kober, Gladys; Nielsen, Krister E.; Wahlgren, Glenn M., E-mail: Kenneth.G.Carpenter@nasa.gov [Deptartment of Physics, Catholic University of America, Washington, DC 20064 (United States)

    2014-10-10

    We present a far-ultraviolet spectrum of the K4 Ib-II supergiant ? Vel obtained with the Hubble Space Telescope's Cosmic Origins Spectrograph (COS) as a part of the SNAPshot program 'SNAPing coronal iron' (GO 11687). The observation covers a wavelength region (1326-1467 ) not previously recorded for ? Vel at a spectral resolving power of R ? 20,000 and displays strong emission and absorption features, superposed on a bright chromospheric continuum. Fluorescent excitation is responsible for much of the observed emission, mainly powered by strong H I Ly? and the O I (UV 2) triplet emission near ?1304. The molecular CO and H{sub 2} fluorescences are weaker than in the early-K giant ? Boo while the Fe II and Cr II lines, also pumped by H I Ly?, are stronger in ? Vel. This pattern of relative line strengths between the two stars is explained by the lower iron-group element abundance in ? Boo, which weakens that star's Fe II and Cr II emission without reducing the molecular fluorescences. The ? Vel spectrum shows fluorescent Fe II, Cr II, and H{sub 2} emission similar to that observed in the M supergiant ? Ori, but more numerous well-defined narrow emissions from CO. The additional CO emissions are visible in the spectrum of ? Vel since that star does not have the cool, opaque circumstellar shells that surround ? Ori and produce broad circumstellar CO (A-X) band absorptions that hide those emissions in the cooler star. The presence of Si IV emission in ? Vel indicates a ?8 10{sup 4} K plasma that is mixed into the cooler chromosphere. Evidence of the stellar wind is seen in the C II ??1334,1335 lines and in the blueshifted Fe II and Ni II wind absorption lines. Line modeling using Sobolev with Exact Integration for the C II lines indicates a larger terminal velocity (?45 versus ?30 km s{sup 1}) and turbulence (?27 versus <21 km s{sup 1}) with a more quickly accelerating wind (? = 0.35 versus 0.7) at the time of this COS observation in 2010 than derived from Goddard High Resolution Spectrograph data obtained in 1994. The Fe II and Ni II absorptions are blueshifted by 7.6 km s{sup 1} relative to the chromospheric emission, suggesting formation in lower levels of the accelerating wind and their widths indicate a higher turbulence in the ? Vel wind compared to ? Ori.

  6. Photoelectron imaging and theoretical study on the structure and chemical binding of the mixed-ligand M(I) complexes, [HMSH]{sup ?} (M = Cu, Ag, and Au)

    SciTech Connect (OSTI)

    Qin, Zhengbo; Liu, Zhiling; Cong, Ran; Xie, Hua; Tang, Zichao, E-mail: zctang@dicp.ac.cn, E-mail: fanhj@dicp.ac.cn; Fan, Hongjun, E-mail: zctang@dicp.ac.cn, E-mail: fanhj@dicp.ac.cn [State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China)] [State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China)

    2014-03-21

    We have reported a combined photoelectron imaging and theoretical study on gaseous mixed-ligand M(I) complexes of [HMSH]{sup ?} (M = Cu, Ag, and Au). With the aid of Franck-Condon simulations, vibrationally resolved photoelectron spectra yield accurate electron affinities of 3.269(6), 3.669(10), and 3.591(6) eV for [HCuSH], [HAgSH], and [HAuSH], respectively. And low-frequency modes are observed: 368(12) cm{sup ?1} for [HCuSH], 286(12) cm{sup ?1} for [HAgSH], and 327(12) cm{sup ?1} for [HAuSH], respectively. Extensive theoretical calculations are performed to aid in the spectral assignments and the calculated values agree well with the experimental observations. Although the S and H atoms have little discrepancy in electronegativity (2.20 for H and 2.54 for S), distinct bonding properties are demonstrated between HM and MS bond. It is revealed that there exists significant ionic bonding between MS in [HMSH]{sup ?} (M = Cu, Ag, and Au), while a gradual transition from ionic behavior between HCu in [HCuSH]{sup ?} to quite strong covalent bonding between HAu in [HAuSH]{sup ?}, supported by a variety of chemical bonding analyses.

  7. Full self-consistency versus quasiparticle self-consistency in diagrammatic approaches: Exactly solvable two-site Hubbard model

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

    Kutepov, A. L.

    2015-07-22

    Self-consistent solutions of Hedin's equations (HE) for the two-site Hubbard model (HM) have been studied. They have been found for three-point vertices of increasing complexity (Γ = 1 (GW approximation), Γ₁ from the first-order perturbation theory, and the exact vertex ΓE). Comparison is made between the cases when an additional quasiparticle (QP) approximation for Green's functions is applied during the self-consistent iterative solving of HE and when QP approximation is not applied. Results obtained with the exact vertex are directly related to the present open question—which approximation is more advantageous for future implementations, GW + DMFT or QPGW + DMFT.more » It is shown that in a regime of strong correlations only the originally proposed GW + DMFT scheme is able to provide reliable results. Vertex corrections based on Perturbation Theory systematically improve the GW results when full self-consistency is applied. The application of QP self-consistency combined with PT vertex corrections shows similar problems to the case when the exact vertex is applied combined with QP sc. An analysis of Ward Identity violation is performed for all studied in this work's approximations and its relation to the general accuracy of the schemes used is provided.« less

  8. Collaborative Lubricating Oil Study on Emissions: November 28, 2006 - March 31, 2011

    SciTech Connect (OSTI)

    Carroll, J. N.; Khalek, I. A.; Smith, L. R.; Fujita, E.; Zielinska, B.

    2011-10-01

    The Collaborative Lubricating Oil Study on Emissions (CLOSE) project was a pilot investigation of how fuels and crankcase lubricants contribute to the formation of particulate matter (PM) and semi-volatile organic compounds (SVOC) in vehicle exhaust. As limited vehicles were tested, results are not representative of the whole on-road fleet. Long-term effects were not investigated. Pairs of vehicles (one normal PM emitting, one high-PM emitting) from four categories were selected: light-duty (LD) gasoline cars, medium-duty (MD) diesel trucks, heavy-duty (HD) natural-gas-fueled buses, and HD diesel buses. HD vehicles procured did not exhibit higher PM emissions, and thus were labeled high mileage (HM). Fuels evaluated were non-ethanol gasoline (E0), 10 percent ethanol (E10), conventional low-sulfur TxLED diesel, 20% biodiesel (B20), and natural gas. Temperature effects (20 degrees F, 72 degrees F) were evaluated on LD and MD vehicles. Lubricating oil vintage effects (fresh and aged) were evaluated on all vehicles. LD and MD vehicles were operated on a dynamometer over the California Unified Driving Cycle, while HD vehicles followed the Heavy Duty Urban Dynamometer Driving Schedule. Regulated and unregulated emissions were measured. Chemical markers from the unregulated emissions measurements and a tracer were utilized to estimate the lubricant contribution to PM.

  9. For Stimul-Responsive Polymers with Enhanced Efficiency in Reservoir Recovery Processes

    SciTech Connect (OSTI)

    Charles McCormick; Roger Hester

    2003-02-28

    Acrylamide-based hydrophobically modified (HM) polybetaines containing N-butylphenylacrylamide (BPAM) and varying amounts of either sulfobetaine (3-(2-acrylamido-2-methylpropanedimethylammonio)-1-propanesulfonate, AMPDAPS) or carboxybetaine (4-(2-acrylamido-2-methylpropyldimethylammonio) butanoate, AMPDAB) comonomers were synthesized via micellar copolymerization. The terpolymers were characterized via {sup 13}C NMR and UV spectroscopies, classical and dynamic light scattering, and potentiometric titration. The response of aqueous polymer solutions to various external stimuli, including changes in solution pH, electrolyte concentration, and the addition of small molecule surfactants, was investigated using surface tension and rheological measurements. Low charge density terpolymers were found to show greater viscosity enhancement upon the addition of surfactant compared to the high charge density terpolymers. The addition of sodium dodecyl sulfate (SDS) produced the largest maximum in solution viscosity, while N-dodecyl-N,N,N-trimethylammonium bromide (DTAB), N-dodecyl-N,N-dimethylammonio-1-propanesulfonate (SB3-12), and Triton X-100 tended to show reduced viscosity enhancement. In most cases, the high charge density carboxybetaine terpolymer exhibited diminished solution viscosities upon surfactant addition. In our last report, we discussed solution thermodynamic theory that described changes in polymer coil conformation as a function of solution temperature and polymer molecular weight. These polymers contained no ionic charges. In this report, we expand polymer solution theory to account for the electrostatic interactions present in solutions of charged polymers. Polymers with ionic charges are referred to as polyions or polyelectrolytes.

  10. Estimation of average burnup of damaged fuels loaded in Fukushima Dai-ichi reactors by using the {sup 134}Cs/{sup 137}Cs ratio method

    SciTech Connect (OSTI)

    Endo, T.; Sato, S.; Yamamoto, A.

    2012-07-01

    Average burnup of damaged fuels loaded in Fukushima Dai-ichi reactors is estimated, using the {sup 134}Cs/{sup 137}Cs ratio method for measured radioactivities of {sup 134}Cs and {sup 137}Cs in contaminated soils within the range of 100 km from the Fukushima Dai-ichi nuclear power plants. As a result, the measured {sup 134}Cs/{sup 137}Cs ratio from the contaminated soil is 0.996{+-}0.07 as of March 11, 2011. Based on the {sup 134}Cs/{sup 137}Cs ratio method, the estimated burnup of damaged fuels is approximately 17.2{+-}1.5 [GWd/tHM]. It is noted that the numerical results of various calculation codes (SRAC2006/PIJ, SCALE6.0/TRITON, and MVP-BURN) are almost the same evaluation values of {sup 134}Cs/ {sup 137}Cs ratio with same evaluated nuclear data library (ENDF-B/VII.0). The void fraction effect in depletion calculation has a major impact on {sup 134}Cs/{sup 137}Cs ratio compared with the differences between JENDL-4.0 and ENDF-B/VII.0. (authors)

  11. Energy and greenhouse gas emission effects of corn and cellulosic ethanol with technology improvements and land use changes.

    SciTech Connect (OSTI)

    Wang, M.; Han, J.; Haq, Z; Tyner, .W.; Wu, M.; Elgowainy, A.

    2011-05-01

    Use of ethanol as a transportation fuel in the United States has grown from 76 dam{sup 3} in 1980 to over 40.1 hm{sup 3} in 2009 - and virtually all of it has been produced from corn. It has been debated whether using corn ethanol results in any energy and greenhouse gas benefits. This issue has been especially critical in the past several years, when indirect effects, such as indirect land use changes, associated with U.S. corn ethanol production are considered in evaluation. In the past three years, modeling of direct and indirect land use changes related to the production of corn ethanol has advanced significantly. Meanwhile, technology improvements in key stages of the ethanol life cycle (such as corn farming and ethanol production) have been made. With updated simulation results of direct and indirect land use changes and observed technology improvements in the past several years, we conducted a life-cycle analysis of ethanol and show that at present and in the near future, using corn ethanol reduces greenhouse gas emission by more than 20%, relative to those of petroleum gasoline. On the other hand, second-generation ethanol could achieve much higher reductions in greenhouse gas emissions. In a broader sense, sound evaluation of U.S. biofuel policies should account for both unanticipated consequences and technology potentials. We maintain that the usefulness of such evaluations is to provide insight into how to prevent unanticipated consequences and how to promote efficient technologies with policy intervention.

  12. Modification-dependent restriction endonuclease, MspJI, flips 5-methylcytosine out of the DNA helix

    SciTech Connect (OSTI)

    Horton, J. R.; Wang, H.; Mabuchi, M. Y.; Zhang, X.; Roberts, R. J.; Zheng, Y.; Wilson, G. G.; Cheng, X.

    2014-09-27

    MspJI belongs to a family of restriction enzymes that cleave DNA containing 5-methylcytosine (5mC) or 5-hydroxymethylcytosine (5hmC). MspJI is specific for the sequence 5(h)mC-N-N-G or A and cleaves with some variability 9/13 nucleotides downstream. Earlier, we reported the crystal structure of MspJI without DNA and proposed how it might recognize this sequence and catalyze cleavage. Here we report its co-crystal structure with a 27-base pair oligonucleotide containing 5mC. This structure confirms that MspJI acts as a homotetramer and that the modified cytosine is flipped from the DNA helix into an SRA-like-binding pocket. We expected the structure to reveal two DNA molecules bound specifically to the tetramer and engaged with the enzyme's two DNA-cleavage sites. A coincidence of crystal packing precluded this organization, however. We found that each DNA molecule interacted with two adjacent tetramers, binding one specifically and the other non-specifically. The latter interaction, which prevented cleavage-site engagement, also involved base flipping and might represent the sequence-interrogation phase that precedes specific recognition. MspJI is unusual in that DNA molecules are recognized and cleaved by different subunits. Such interchange of function might explain how other complex multimeric restriction enzymes act.

  13. Modification-dependent restriction endonuclease, MspJI, flips 5-methylcytosine out of the DNA helix

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

    Horton, J. R.; Wang, H.; Mabuchi, M. Y.; Zhang, X.; Roberts, R. J.; Zheng, Y.; Wilson, G. G.; Cheng, X.

    2014-09-27

    MspJI belongs to a family of restriction enzymes that cleave DNA containing 5-methylcytosine (5mC) or 5-hydroxymethylcytosine (5hmC). MspJI is specific for the sequence 5(h)mC-N-N-G or A and cleaves with some variability 9/13 nucleotides downstream. Earlier, we reported the crystal structure of MspJI without DNA and proposed how it might recognize this sequence and catalyze cleavage. Here we report its co-crystal structure with a 27-base pair oligonucleotide containing 5mC. This structure confirms that MspJI acts as a homotetramer and that the modified cytosine is flipped from the DNA helix into an SRA-like-binding pocket. We expected the structure to reveal two DNAmore » molecules bound specifically to the tetramer and engaged with the enzyme's two DNA-cleavage sites. A coincidence of crystal packing precluded this organization, however. We found that each DNA molecule interacted with two adjacent tetramers, binding one specifically and the other non-specifically. The latter interaction, which prevented cleavage-site engagement, also involved base flipping and might represent the sequence-interrogation phase that precedes specific recognition. MspJI is unusual in that DNA molecules are recognized and cleaved by different subunits. Such interchange of function might explain how other complex multimeric restriction enzymes act.« less

  14. Hydride compositions

    DOE Patents [OSTI]

    Lee, Myung, W.

    1994-01-01

    Disclosed are a composition for use in storing hydrogen and a method for making the composition. The composition comprises a mixture of two or more hydrides, each hydride having a different series of hydrogen sorption isotherms that contribute to the overall isotherms of the mixture. The hydrides are chosen so that the isotherms of the mixture have regions wherein the H equilibrium pressure increases with increasing hydrogen, preferably linearly. The isotherms of the mixture can be adjusted by selecting hydrides with different isotherms and by varying the amounts of the individual hydrides, or both. Preferably, the mixture is made up of hydrides that have isotherms with substantially flat plateaus and in nearly equimolar amounts. The composition is activated by degassing, exposing to H, and then heating below the softening temperature of any of the constituents. When the composition is used to store hydrogen, its hydrogen content can be found simply by measuring P{sub H}{sub 2} and determining H/M from the isothermic function of the composition.

  15. Hydride compositions

    DOE Patents [OSTI]

    Lee, Myung W.

    1995-01-01

    A composition for use in storing hydrogen, and a method for making the composition. The composition comprises a mixture of two or more hydrides, each hydride having a different series of hydrogen sorption isotherms that contribute to the overall isotherms of the mixture. The hydrides are chosen so that the isotherms of the mixture have regions wherein the hydrogen equilibrium pressure increases with increasing hydrogen, preferably linearly. The isotherms of the mixture can be adjusted by selecting hydrides with different isotherms and by varying the amounts of the individual hydrides, or both. Preferably, the mixture is made up of hydrides that have isotherms with substantially flat plateaus and in nearly equimolar amounts. The composition is activated by degassing, exposing to hydrogen and then heating at a temperature below the softening temperature of any of the. constituents so that their chemical and structural integrity is preserved. When the composition is used to store hydrogen, its hydrogen content can be found simply by measuring P.sub.H.sbsb.2 and determining H/M from the isothermic function of the composition.

  16. A Validation Study of Pin Heat Transfer for MOX Fuel Based on the IFA-597 Experiments

    SciTech Connect (OSTI)

    Phillippe, Aaron M; Clarno, Kevin T; Banfield, James E; Ott, Larry J; Philip, Bobby; Berrill, Mark A; Sampath, Rahul S; Allu, Srikanth; Hamilton, Steven P

    2014-01-01

    Abstract The IFA-597 (Integrated Fuel Assessment) experiments from the International Fuel Performance Experiments (IFPE) database were designed to study the thermal behavior of mixed oxide (MOX) fuel and the effects of an annulus on fission gas release in light-water-reactor fuel. An evaluation of nuclear fuel pin heat transfer in the FRAPCON-3.4 and Exnihilo codes for MOX fuel systems was performed, with a focus on the first 20 time steps ( 6 GWd/MT(iHM)) for explicit comparison between the codes. In addition, sensitivity studies were performed to evaluate the effect of the radial power shape and approximations to the geometry to account for the thermocouple hole, dish, and chamfer. The analysis demonstrated relative agreement for both solid (rod 1) and annular (rod 2) fuel in the experiment, demonstrating the accuracy of the codes and their underlying material models for MOX fuel, while also revealing a small energy loss artifact in how gap conductance is currently handled in Exnihilo for chamfered fuel pellets. The within-pellet power shape was shown to significantly impact the predicted centerline temperatures. This has provided an initial benchmarking of the pin heat transfer capability of Exnihilo for MOX fuel with respect to a well-validated nuclear fuel performance code.

  17. International Collaborations on Engineered Barrier Systems: Brief Overview of SKB-EBS Activities.

    SciTech Connect (OSTI)

    Jove-Colon, Carlos F.

    2015-10-01

    Research collaborations with international partners on the behavior and performance of engineered barrier systems (EBS) are an important aspect of the DOE-NE Used Fuel Disposition Campaign strategy in the evaluation of disposal design concepts. These international partnerships are a cost-effective way of engaging in key R&D activities with common goals resulting in effective scientific knowledge exchanges thus enhancing existing and future research programs in the USA. This report provides a brief description of the activities covered by the Swedish Nuclear Fuel and Waste Management Company (SKB) EBS Task Force (TF) (referred hereafter as SKB EBS TF) and potential future directions for engagement of the DOE-NE UFDC program in relevant R&D activities. Emphasis is given to SKB EBS TF activities that are still ongoing and aligned to the UFDC R&D program. This include utilization of data collected in the bentonite rock interaction experiment (BRIE) and data sets from benchmark experiments produced by the chemistry or C part of the SKB EBS TF. Potential applications of information generated by this program include comparisons/tests between model and data (e.g., reactive diffusion), development and implementation of coupled-process models (e.g., HM), and code/model benchmarking.

  18. A Fission Gas Release Model for High-Burnup LWR ThO{sub 2}-UO{sub 2} Fuel

    SciTech Connect (OSTI)

    Long, Yun; Yi Yuan; Kazimi, Mujid S.; Ballinger, Ronald G.; Pilat, Edward E.

    2002-06-15

    Fission gas release in thoria-urania fuel has been investigated by creating a specially modified FRAPCON-3 code. Because of the reduced buildup of {sup 239}Pu and a flatter distribution of {sup 233}U, the new model THUPS (Thoria-Urania Power Shape) was developed to calculate the radial power distribution, including the effects of both plutonium and {sup 233}U. Additionally, a new porosity model for the rim region was introduced at high burnup. The mechanisms of fission gas release in ThO{sub 2}-UO{sub 2} fuel are expected to be essentially similar to those of UO{sub 2} fuel; therefore, the general formulations of the existing fission gas release models in FRAPCON-3 were retained. However, the gas diffusion coefficient was adjusted to a lower level to account for the smaller observed release fraction in the thoria-based fuel. To model the accelerated fission gas release at high burnup properly, a new athermal fission gas release model was introduced. The modified version of FRAPCON-3 was calibrated using the measured fission gas release data from the light water breeder reactor. Using the new model to calculate the gas release in typical pressurized water reactor hot pins gives data that indicate that the ThO{sub 2}-UO{sub 2} fuel will have considerably lower fission gas release above a burnup of 50 MWd/kg HM.

  19. Annual report, spring 2015. Alternative chemical cleaning methods for high level waste tanks-corrosion test results

    SciTech Connect (OSTI)

    Wyrwas, R. B.

    2015-07-06

    The testing presented in this report is in support of the investigation of the Alternative Chemical Cleaning program to aid in developing strategies and technologies to chemically clean radioactive High Level Waste tanks prior to tank closure. The data and conclusions presented here were the examination of the corrosion rates of A285 carbon steel and 304L stainless steel when interacted with the chemical cleaning solution composed of 0.18 M nitric acid and 0.5 wt. % oxalic acid. This solution has been proposed as a dissolution solution that would be used to remove the remaining hard heel portion of the sludge in the waste tanks. This solution was combined with the HM and PUREX simulated sludge with dilution ratios that represent the bulk oxalic cleaning process (20:1 ratio, acid solution to simulant) and the cumulative volume associated with multiple acid strikes (50:1 ratio). The testing was conducted over 28 days at 50°C and deployed two methods to invest the corrosion conditions; passive weight loss coupon and an active electrochemical probe were used to collect data on the corrosion rate and material performance. In addition to investigating the chemical cleaning solutions, electrochemical corrosion testing was performed on acidic and basic solutions containing sodium permanganate at room temperature to explore the corrosion impacts if these solutions were to be implemented to retrieve remaining actinides that are currently in the sludge of the tank.

  20. Needs assessment activity report. Revision 1

    SciTech Connect (OSTI)

    1994-11-01

    As part of a Transportation Management Division task (TMD), the Packaging Programs and Testing Group within Westinghouse Hanford Company (WHC) has assessed the packaging needs of some of the mid- and small-sized US Department of Energy (DOE) sites by visiting them and meeting with their transportation and packaging personnel. To date, ten DOE facilities have been visited. As a result, these sites have been informed of some of the packaging activities that TMD has sponsored and is sponsoring, have been appraised of possible upcoming changes to transportation regulations, have discussed their short-term packaging needs, and have shared unique packaging they have developed which may be of use to other DOE facilities. Program successes include developing a questionnaire that discusses the potential impact of US Department of Transportation (DOT) Docket HM-169A, Transportation Regulations; Compatibility with Regulations of the International Atomic Energy Agency; Notice of Proposed Rule (DOT 1989), discovery of a need for a reusable Type A liquid sample packaging and starting its development within another TMD task, coordinating resources between Fermi Laboratory and Argonne National Laboratory, and widening the distribution of WHC-EP-0558, Test and Evaluation Document for DOT Specification 7A Type A Packaging (WHC 1994).

  1. Elastic Neutron Scattering at 96 MeV

    SciTech Connect (OSTI)

    Hildebrand, A.; Blomgren, J.; Atac, A.; Bergenwall, B.; Johansson, C.; Klug, J.; Mermod, P.; Nilsson, L.; Pomp, S.; Esterlund, M.; Dangtip, S.; Tippawan, U.; Phansuke, P.; Jonsson, O.; Renberg, P.-U.; Prokofiev, A.; Nadel-Turonski, P.; Elmgren, K.; Olsson, N.; Blideanu, V.

    2005-05-24

    A facility for detection of scattered neutrons in the energy interval 50-130 MeV, SCANDAL (SCAttered Nucleon Detection AssembLy), has recently been installed at the 20 - 180-MeV neutron beam line of The Svedberg Laboratory, Uppsala. Elastic neutron scattering from 12C, 16O, 56Fe, 89Y, and 208Pb has been studied at 96 MeV in the 10-70 deg. interval. The results from 12C and 208Pb have recently been published,6 while the data from 16O, 56Fe, and 89Y are under analysis. The achieved energy resolution, 3.7 MeV, is about an order of magnitude better than for any previous experiment above 65 MeV incident energy. The present experiment represents the highest neutron energy where the ground state has been resolved from the first excited state in neutron scattering. A novel method for normalization of the absolute scale of the cross section has been used. The estimated normalization uncertainty, 3%, is unprecedented for a neutron-induced differential cross section measurement on a nuclear target. The results are compared with modern optical model predictions, based on phenomenology or microscopic theory. Applications for these measurements are nuclear-waste incineration, single-event upsets in electronics, and fast-neutron therapy.

  2. METHOD AND APPARATUS FOR THE DETECTION OF LEAKS IN PIPE LINES

    DOE Patents [OSTI]

    Jefferson, S.; Cameron, J.F.

    1961-11-28

    A method is described for detecting leaks in pipe lines carrying fluid. The steps include the following: injecting a radioactive solution into a fluid flowing in the line; flushing the line clear of the radioactive solution; introducing a detector-recorder unit, comprising a radioactivity radiation detector and a recorder which records the detector signal over a time period at a substantially constant speed, into the line in association with a go-devil capable of propelling the detector-recorder unit through the line in the direction of the fluid flow at a substantia1ly constant velocity; placing a series of sources of radioactivity at predetermined distances along the downstream part of the line to make a characteristic signal on the recorder record at intervals corresponding to the location of said sources; recovering the detector-recorder unit at a downstream point along the line; transcribing the recorder record of any radioactivity detected during the travel of the detector- recorder unit in terms of distance along the line. (AEC)

  3. Quasar-Lyman ? forest cross-correlation from BOSS DR11: Baryon Acoustic Oscillations

    SciTech Connect (OSTI)

    Font-Ribera, Andreu; Kirkby, David; Blomqvist, Michael; Busca, Nicolas; Aubourg, ric; Bautista, Julian; Ross, Nicholas P.; Bailey, Stephen; Beutler, Florian; Carithers, Bill; Slosar, Ane; Rich, James; Delubac, Timothe; Bhardwaj, Vaishali; Bizyaev, Dmitry; Brewington, Howard; Brinkmann, Jon; Brownstein, Joel R.; Dawson, Kyle S.; and others

    2014-05-01

    We measure the large-scale cross-correlation of quasars with the Ly? forest absorption, using over 164,000 quasars from Data Release 11 of the SDSS-III Baryon Oscillation Spectroscopic Survey. We extend the previous study of roughly 60,000 quasars from Data Release 9 to larger separations, allowing a measurement of the Baryonic Acoustic Oscillation (BAO) scale along the line of sight c/(H(z = 2.36)r{sub s}) = 9.00.3 and across the line of sight D{sub A}(z = 2.36)/r{sub s} = 10.80.4, consistent with CMB and other BAO data. Using the best fit value of the sound horizon from Planck data (r{sub s} = 147.49Mpc), we can translate these results to a measurement of the Hubble parameter of H(z = 2.36) = 2268kms{sup ?1}Mpc{sup ?1} and of the angular diameter distance of D{sub A}(z = 2.36) = 159060Mpc. The measured cross-correlation function and an update of the code to fit the BAO scale (baofit) are made publicly available.

  4. A star-forming shock front in radio galaxy 4C+41.17 resolved with laser-assisted adaptive optics spectroscopy

    SciTech Connect (OSTI)

    Steinbring, Eric

    2014-07-01

    Near-infrared integral-field spectroscopy of redshifted [O III], H?, and optical continuum emission from the z = 3.8 radio galaxy 4C+41.17 is presented, obtained with the laser-guide-star adaptive optics facility on the Gemini North telescope. Employing a specialized dithering technique, a spatial resolution of 0.''10, or 0.7 kpc, is achieved in each spectral element, with a velocity resolution of ?70 km s{sup 1}. Spectra similar to local starbursts are found for bright knots coincident in archival Hubble Space Telescope ( HST) rest-frame ultraviolet images, which also allows a key line diagnostic to be mapped together with new kinematic information. There emerges a clearer picture of the nebular emission associated with the jet in 8.3 GHz and 15 GHz Very Large Array maps, closely tied to a Ly?-bright shell-shaped structure seen with HST. This supports a previous interpretation of that arc tracing a bow shock, inducing ?10{sup 1011} M {sub ?} star formation regions that comprise the clumpy broadband optical/ultraviolet morphology near the core.

  5. Measurements of Martin-Puplett Interferometer Limitations using Blackbody Source

    SciTech Connect (OSTI)

    Evtushenko, Pavel E.; Klopf, John M.

    2013-06-01

    Frequency domain measurements with Martin-Puplett interferometer is one of a few techniques capable of bunch length measurements at the level of ~ 100 fs. As the bunch length becomes shorter, it is important to know and be able to measure the limitations of the instrument in terms of shortest measurable bunch length. In this paper we describe an experiment using a blackbody source with the modified Martin-Puplett interferometer that is routine- ly used for bunch length measurements at the JLab FEL, as a way to estimate the shortest, measurable bunch length. The limitation comes from high frequency cut-off of the wire-grid polarizer currently used and is estimated to be 50 fs RMS. The measurements are made with the same Golay cell detector that is used for beam measure- ments. We demonstrate that, even though the blackbody source is many orders of magnitude less bright than the coherent transition or synchrotron radiation, it can be used for the measurements and gives a very good signal to noise ratio in combination with lock-in detection. We also compare the measurements made in air and in vacuum to characterize the very strong effect of the atmospheric absorption.

  6. A dual-channel, curved-crystal spectrograph for petawatt laser, x-ray backlighter source studies

    SciTech Connect (OSTI)

    Theobald, W.; Stoeckl, C.; Jaanimagi, P. A.; Nilson, P. M.; Storm, M.; Meyerhofer, D. D.; Sangster, T. C.; Hey, D.; MacKinnon, A. J.; Park, H.-S.; Patel, P. K.; Shepherd, R.; Snavely, R. A.; Key, M. H.; King, J. A.; Zhang, B.; Stephens, R. B.; Akli, K. U.; Highbarger, K.; Daskalova, R. L.; and others

    2009-08-15

    A dual-channel, curved-crystal spectrograph was designed to measure time-integrated x-ray spectra in the {approx}1.5 to 2 keV range (6.2-8.2 A wavelength) from small-mass, thin-foil targets irradiated by the VULCAN petawatt laser focused up to 4x10{sup 20} W/cm{sup 2}. The spectrograph consists of two cylindrically curved potassium-acid-phthalate crystals bent in the meridional plane to increase the spectral range by a factor of {approx}10 compared to a flat crystal. The device acquires single-shot x-ray spectra with good signal-to-background ratios in the hard x-ray background environment of petawatt laser-plasma interactions. The peak spectral energies of the aluminum He{sub {alpha}} and Ly{sub {alpha}} resonance lines were {approx}1.8 and {approx}1.0 mJ/eV sr ({approx}0.4 and 0.25 J/A sr), respectively, for 220 J, 10 ps laser irradiation.

  7. THE EXTRAGALACTIC BACKGROUND LIGHT FROM THE MEASUREMENTS OF THE ATTENUATION OF HIGH-ENERGY GAMMA-RAY SPECTRUM

    SciTech Connect (OSTI)

    Gong Yan; Cooray, Asantha [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States)

    2013-07-20

    The attenuation of high-energy gamma-ray spectrum due to the electron-positron pair production against the extragalactic background light (EBL) provides an indirect method to measure the EBL of the universe. We use the measurements of the absorption features of the gamma-rays from blazars as seen by the Fermi Gamma-ray Space Telescope to explore the EBL flux density and constrain the EBL spectrum, star formation rate density (SFRD), and photon escape fraction from galaxies out to z = 6. Our results are basically consistent with the existing determinations of the quantities. We find a larger photon escape fraction at high redshifts, especially at z = 3, compared to the result from recent Ly{alpha} measurements. Our SFRD result is consistent with the data from both gamma-ray burst and ultraviolet (UV) observations in the 1{sigma} level. However, the average SFRD we obtain at z {approx}> 3 matches the gamma-ray data better than the UV data. Thus our SFRD result at z {approx}> 6 favors the fact that star formation alone is sufficiently high enough to reionize the universe.

  8. THE GEOMETRY EFFECTS OF AN EXPANDING UNIVERSE ON THE DETECTION OF COOL NEUTRAL GAS AT HIGH REDSHIFT

    SciTech Connect (OSTI)

    Curran, S. J.

    2012-03-20

    Recent high-redshift surveys for 21 cm absorption in damped Ly{alpha} absorption systems (DLAs) take the number of published searches at z{sub abs} > 2 to 25, the same number as at z{sub abs} < 2, although the detection rate at high redshift remains significantly lower (20% compared to 60%). Using the known properties of the DLAs to estimate the unknown profile widths of the 21 cm non-detections and including the limits via a survival analysis, we show that the mean spin temperature/covering factor degeneracy at high redshift is, on average, double that of the low-redshift sample. This value is significantly lower than the previous factor of eight for the spin temperatures and is about the same factor as in the angular diameter distance ratios between the low- and high-redshift samples. That is, without the need for the several pivotal assumptions, which lead to an evolution in the spin temperature, we show that the observed distribution of 21 cm detections in DLAs can be accounted for by the geometry effects of an expanding universe. That is, as yet there is no evidence of the spin temperature of gas-rich galaxies evolving with redshift.

  9. A FOURTH H I 21 cm ABSORPTION SYSTEM IN THE SIGHT LINE OF MG J0414+0534: A RECORD FOR INTERVENING ABSORBERS

    SciTech Connect (OSTI)

    Tanna, A.; Webb, J. K.; Curran, S. J.; Whiting, M. T.; Bignell, C.

    2013-08-01

    We report the detection of a strong H I 21 cm absorption system at z = 0.5344, as well as a candidate system at z = 0.3389, in the sight line toward the z = 2.64 quasar MG J0414+0534. This, in addition to the absorption at the host redshift and the other two intervening absorbers, takes the total to four (possibly five). The previous maximum number of 21 cm absorbers detected along a single sight line is two and so we suspect that this number of gas-rich absorbers is in some way related to the very red color of the background source. Despite this, no molecular gas (through OH absorption) has yet been detected at any of the 21 cm redshifts, although, from the population of 21 cm absorbers as a whole, there is evidence for a weak correlation between the atomic line strength and the optical-near-infrared color. In either case, the fact that so many gas-rich galaxies (likely to be damped Ly{alpha} absorption systems) have been found along a single sight line toward a highly obscured source may have far-reaching implications for the population of faint galaxies not detected in optical surveys, a possibility which could be addressed through future wide-field absorption line surveys with the Square Kilometer Array.

  10. THE LOW-REDSHIFT INTERGALACTIC MEDIUM AS SEEN IN ARCHIVAL LEGACY HST/STIS AND FUSE DATA

    SciTech Connect (OSTI)

    Tilton, Evan M.; Danforth, Charles W.; Michael Shull, J. [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, 389-UCB, Boulder, CO 80309 (United States); Ross, Teresa L., E-mail: evan.tilton@colorado.edu, E-mail: charles.danforth@colorado.edu, E-mail: michael.shull@colorado.edu, E-mail: rosst@nmsu.edu [Department of Astronomy, New Mexico State University, Las Cruces, NM 88003 (United States)

    2012-11-10

    We present a comprehensive catalog of ultraviolet (HST/STIS and FUSE) absorbers in the low-redshift intergalactic medium (IGM) at z < 0.4. The catalog draws from much of the extensive literature on IGM absorption and reconciles discrepancies among several previous catalogs through a critical evaluation of all reported absorption features in light of new HST/COS data. We report on 746 H I absorbers down to a rest-frame equivalent width of 12 mA over a maximum redshift path length {Delta}z = 5.38. We also confirm 111 O VI absorbers, 29 C IV absorbers, and numerous absorption lines due to other metal ions. We characterize the bivariate distribution of absorbers in redshift and column density as a power law, {partial_derivative}{sup 2}N/{partial_derivative}z{partial_derivative}N) {proportional_to} N{sup -{beta}}, where {beta} = 2.08 {+-} 0.12 for O VI and {beta} = 1.68 {+-} 0.03 for H I. Utilizing a more sophisticated accounting technique than past work, our catalog accounts for {approx}43% of the baryons: 24% {+-} 2% in the photoionized Ly{alpha} forest and 19% {+-} 2% in the warm-hot IGM as traced by O VI. We discuss the large systematic effects of various assumed metallicities and ionization states on these calculations, and we implement recent simulation results in our estimates.

  11. HST/COS OBSERVATIONS OF THIRTEEN NEW He II QUASARS

    SciTech Connect (OSTI)

    Syphers, David; Anderson, Scott F.; Zheng Wei; Meiksin, Avery; Schneider, Donald P.; York, Donald G.

    2012-04-15

    The full reionization of intergalactic helium was a major event in the history of the intergalactic medium (IGM), and UV observations of the He II Gunn-Peterson trough allow us to characterize the end of this process at z {approx} 3. Due to intervening hydrogen absorption, quasars allowing such study are rare, with only 33 known in the literature, and most of those are very recent discoveries. We expand on our previous discovery work, and present 13 new He II quasars with redshifts 2.82 < z < 3.77, here selected with {approx}80% efficiency, and including several that are much brighter than the vast majority of those previously known. This is the largest sample of uniformly observed He II quasars covering such a broad redshift range, and they show evidence of IGM opacity increasing with redshift, as expected for the helium reionization epoch. No evidence of He II Ly{alpha} quasar emission is seen in individual or averaged spectra, posing a problem for standard models of the broad-line region. The current rapid advance in the study of He II quasars has been greatly facilitated by the Cosmic Origins Spectrograph on the Hubble Space Telescope, and we discuss the instrumental and other subtleties that must be taken into account in IGM He II observations.

  12. Evolution of Elastic X-ray Scattering in Laser-Shocked Warm Dense Li

    SciTech Connect (OSTI)

    Kugland, N L; Gregori, G; Bandyopadhyay, S; Brenner, C; Brown, C; Constantin, C; Glenzer, S H; Khattak, F; Kritcher, A L; Niemann, C; Otten, A; Pasley, J; Pelka, A; Roth, M; Spindloe, C; Riley, D

    2009-06-02

    We have studied the dynamics of warm dense Li with near-elastic x-ray scattering. Li foils were heated and compressed using shock waves driven by 4 ns long laser pulses. Separate 1 ns long laser pulses were used to generate a bright source of 2.96 keV Cl Ly-{alpha} photons for x-ray scattering, and the spectrum of scattered photons was recorded at a scattering angle of 120{sup o} using a HOPG crystal operated in the von Hamos geometry. A variable delay between the heater and backlighter laser beams measured the scattering time evolution. Comparison with radiation hydrodynamics simulations shows that the plasma is highly coupled during the first several nanoseconds, then relaxes to a moderate coupling state at later times. Near-elastic scattering amplitudes have been successfully simulated using the screened one-component plasma model. Our main finding is that the near-elastic scattering amplitudes are quite sensitive to the mean ionization state {bar Z}, and by extension to the choice of ionization model in the radiation-hydrodynamics simulations used to predict plasma properties within the shocked Li.

  13. The Eighth Data Release of the Sloan Digital Sky Survey: First Data from SDSS-III

    SciTech Connect (OSTI)

    Aihara, Hiroaki; Prieto, Carlos Allende; An, Deokkeun; Anderson, Scott F.; Aubourg, Eric; Balbinot, Eduardo; Beers, Timothy C.; Berlind, Andreas A.; Bickerton, Steven J.; Bizyaev, Dmitry; Blanton, Michael R.; /New York U., CCPP /Penn State U.

    2011-01-01

    The Sloan Digital Sky Survey (SDSS) started a new phase in August 2008, with new instrumentation and new surveys focused on Galactic structure and chemical evolution, measurements of the baryon oscillation feature in the clustering of galaxies and the quasar Ly{alpha} forest, and a radial velocity search for planets around {approx}8000 stars. This paper describes the first data release of SDSS-III (and the eighth counting from the beginning of the SDSS). The release includes 5-band imaging of roughly 5200 deg{sup 2} in the Southern Galactic Cap, bringing the total footprint of the SDSS imaging to 14,555 deg{sup 2}, or over a third of the Celestial Sphere. All the imaging data have been reprocessed with an improved sky-subtraction algorithm and a final, self-consistent recalibration and flat-field determination. This release also includes all data from the second phase of the Sloan Extension for Galactic Understanding and Evolution (SEGUE-2), consisting of spectroscopy of approximately 118,000 stars at both high and low Galactic latitudes. All the more than half a million stellar spectra obtained with the SDSS spectrograph have been reprocessed through an improved stellar parameters pipeline, which has better determination of metallicity for high metallicity stars.

  14. PIK3CA is implicated as an oncogene in ovarian cancer

    SciTech Connect (OSTI)

    Shayesteh, Laleh; Lu, Yiling; Kuo, Wen-Lin; Baldocchi, Russell; Godfrey, Tony; Collins, Colin; Pinkel, Daniel; Powell, Bethan; Mills,Gordon B.; Gray, Joe W.

    1998-03-25

    Ovarian cancer is the leading cause of death from gynecological malignancy and the fourth leading cause of cancer death among American women, yet little is known about its molecular aetiology. Studies using comparative genomic hybridization (CGH) have revealed several regions of recurrent, abnormal, DNA sequence copy number that may encode genes involved in the genesis or progression of the disease. One region at 3q26 found to be increased in copy number in approximately 40 percent of ovarian and other cancers contains PIK3CA, which encodes the p110 a catalytic subunit of phosphatidylinositol 3-kinase(PI3-kinase). The association between PIK3CA copy number and PI3-kinase activity makes PIK3CA a candidate oncogene because a broad range of cancer-related functions have been associated with PI3-kinase mediated signaling. These include proliferation, glucose transport and catabolism, cell adhesion, apoptosis, RAS signaling and oncogenic transformation. In addition, downstream effectors of PI3-kinase,AKT1 and AKT2, have been found to be amplified or activated in human tumors, including ovarian cancer. We show here that PIK3CA is frequently increased in copy number in ovarian cancers, that the increased copy number is associated with increased PIK3CA transcription, p110 a protein expression and PI3-kinase activity and that treatment with the PI3-kinase inhibitor LY294002 decreases proliferation and increases apoptosis. Our observations suggest PIK3CA is an oncogene that has an important role in ovarian cancer.

  15. T?:

    Office of Legacy Management (LM)

    . fj@L(n-- / S~~Jc,~ : T?: F=7Q?! x 3satimzi Leti Crn~:~;r!y of Ohio Ciximati, &io \ Ikl$s & d-/-d Lk *. * i= ' I # a f.-7 ,.a-- " .a.. L...i ;' 3 5 AK. _ ;. _' -~.; TI": 2 ,a -: - o- 4.2. 7 z' c: Ce 2. iLfiLLTs, ~<*~cXI)cT\&' ESp C&z; ~J-iO~~ T' j--$zjJ*aY 9, 1354 .\Tg&, xSL3' 3 --a L. J. A, QIigley, f.!.D, F. J. L!e 2.3 ;T3JECTf;!~ 9F ?Z!LY~ This trig :ms n?c!a to (2.1 ~hxrve hat trSza-C3g test ti a c3lC;-:s3ll tzm.ioat.ia4 of t:ze I'7;lnoce, rmls, ca?cL;s :@Is

  16. HLW Return from France to Germany - 15 Years of Experience in Public Acceptance and Technical Aspects - 12149

    SciTech Connect (OSTI)

    Graf, Wilhelm

    2012-07-01

    Since in 1984 the national reprocessing concept was abandoned the reprocessing abroad was the only existing disposal route until 1994. With the amendment of the Atomic Energy Act in 2001 spent fuel management changed completely since from 1 June 2005 any delivery of spent fuel to reprocessing plants was prohibited and the direct disposal of spent fuel became mandatory. Until 2005 the total amount of spent fuel to be reprocessed abroad added up to 6080 t HM, 5309 t HM thereof in France. The waste generated from reprocessing - alternatively an equivalent amount of radioactive material - has to be returned to the country of origin according to the commercial contracts signed between the German utilities and COGEMA, now AREVA NC, in France and BNFL, now INS in UK. In addition the German and the French government exchanged notes with the obligation of both sides to enable and support the return of reprocessing residues or equivalents to Germany. The return of high active vitrified waste from La Hague to the interim storage facility at Gorleben was demanding from the technical view i. e. the cask design and the transport. Unfortunately the Gorleben area served as a target for nuclear opponents from the first transport in 1996 to the latest one in 2011. The protection against sabotage of the railway lines and mass protests needed highly improved security measures. In France and Germany special working forces and projects have been set up to cope with this extraordinary situation. A complex transport organization was established to involve all parties in line with the German and French requirements during transport. The last transport of vitrified residues from France has been completed successfully so far thus confirming the efficiency of the applied measures. Over 15 years there was and still is worldwide no comparable situation it is still unique. Summing up, the exceptional project handling challenge that resulted from the continuous anti-nuclear civil disobedience in Germany over the whole 15-year long project running time could be faced efficiently. It has to be concluded that despite of all problems the anti-nuclear activities have caused so far, all transports of vitrified HLW have always been completed successfully by adapting the commonly established safety, security and public acceptance measures to the special conditions and needs in Germany and coordinating the activities of all parties involved but at the expense of high costs for industry and government and a challenging operational complexity. Apart from an anticipatory project planning a good communication between all involved industrial parties and the French and the German government was the key to the effective management of such shipments and to minimize the radiological, economic, environmental, public and political impact. The future will show how efficiently the gained experience can be used for further return projects which are to be realized since no reprocessed waste has yet been returned from UK and neither the medium-level nor the low-level radioactive waste has been transferred from France to Germany. (author)

  17. Performance evaluation of two-stage fuel cycle from SFR to PWR

    SciTech Connect (OSTI)

    Fei, T.; Hoffman, E.A.; Kim, T.K.; Taiwo, T.A.

    2013-07-01

    One potential fuel cycle option being considered is a two-stage fuel cycle system involving the continuous recycle of transuranics in a fast reactor and the use of bred plutonium in a thermal reactor. The first stage is a Sodium-cooled Fast Reactor (SFR) fuel cycle with metallic U-TRU-Zr fuel. The SFRs need to have a breeding ratio greater than 1.0 in order to produce fissile material for use in the second stage. The second stage is a PWR fuel cycle with uranium and plutonium mixed oxide fuel based on the design and performance of the current state-of-the-art commercial PWRs with an average discharge burnup of 50 MWd/kgHM. This paper evaluates the possibility of this fuel cycle option and discusses its fuel cycle performance characteristics. The study focuses on an equilibrium stage of the fuel cycle. Results indicate that, in order to avoid a positive coolant void reactivity feedback in the stage-2 PWR, the reactor requires high quality of plutonium from the first stage and minor actinides in the discharge fuel of the PWR needs to be separated and sent back to the stage-1 SFR. The electricity-sharing ratio between the 2 stages is 87.0% (SFR) to 13.0% (PWR) for a TRU inventory ratio (the mass of TRU in the discharge fuel divided by the mass of TRU in the fresh fuel) of 1.06. A sensitivity study indicated that by increasing the TRU inventory ratio to 1.13, The electricity generation fraction of stage-2 PWR is increased to 28.9%. The two-stage fuel cycle system considered in this study was found to provide a high uranium utilization (>80%). (authors)

  18. Catalytic ionic hydrogenation of ketones using tungsten or molybdenum catalysts with increased lifetimes

    DOE Patents [OSTI]

    Bullock, R. Morris; Kimmich, Barbara F. M.; Fagan, Paul J.; Hauptman, Elisabeth

    2003-09-02

    The present invention is a process for the catalytic hydrogenation of ketones and aldehydes to alcohols at low temperatures and pressures using organometallic molybdenum and tungsten complexes and the catalyst used in the process. The reactants include a functional group which is selected from groups represented by the formulas R*(C.dbd.O)R' and R*(C.dbd.O)H, wherein R* and R' are selected from hydrogen or any alkyl or aryl group. The process includes reacting the organic compound in the presence of hydrogen and a catalyst to form a reaction mixture. The catalyst is prepared by reacting Ph.sub.3 C.sup.+ A.sup.- with a metal hydride. A.sup.- represents an anion and can be BF.sub.4.sup.-, PF.sub.6.sup.-, CF.sub.3 SO.sub.3.sup.- or Bar'.sub.4.sup.-, wherein Ar'=3,5-bis(trifluoromethyl)phenyl. The metal hydride is represented by the formula: HM(CO).sub.2 [.eta..sup.5 :.eta..sup.1 --C.sub.5 H.sub.4 (XH.sub.2).sub.n PR.sub.2 ] wherein M represents a molybdenum (Mo) atom or a tungsten (W) atom; X is a carbon atom, a silicon atom or a combination of carbon (C) and silicon (Si) atoms; n is any positive integer; R represents two hydrocarbon groups selected from H, an aryl group and an alkyl group, wherein both R groups can be the same or different. The metal hydride is reacted with Ph.sub.3 C.sup.+ A.sup.- either before reacting with the organic compound or in the reaction mixture.

  19. SLUDGE WASHING AND DEMONSTRATION OF THE DWPF FLOWSHEET IN THE SRNL SHIELDED CELLS FOR SLUDGE BATCH 5 QUALIFICATION

    SciTech Connect (OSTI)

    Pareizs, J; Cj Bannochie, C; Damon Click, D; Dan Lambert, D; Michael Stone, M; Bradley Pickenheim, B; Amanda Billings, A; Ned Bibler, N

    2008-11-10

    Sludge Batch 5 (SB5) is predominantly a combination of H-modified (HM) sludge from Tank 11 that underwent aluminum dissolution in late 2007 to reduce the total mass of sludge solids and aluminum being fed to the Defense Waste Processing Facility (DWPF) and Purex sludge transferred from Tank 7. Following aluminum dissolution, the addition of Tank 7 sludge and excess Pu to Tank 51, Liquid Waste Operations (LWO) provided the Savannah River National Laboratory (SRNL) a 3-L sample of Tank 51 sludge for SB5 qualification. SB5 qualification included washing the sample per LWO plans/projections (including the addition of a Pu/Be stream from H Canyon), DWPF Chemical Process Cell (CPC) simulations, waste glass fabrication (vitrification), and waste glass chemical durability evaluation. This report documents: (1) The washing (addition of water to dilute the sludge supernatant) and concentration (decanting of supernatant) of the Tank 51 qualification sample to adjust sodium content and weight percent insoluble solids to Tank Farm projections. (2) The performance of a DWPF CPC simulation using the washed Tank 51 sample. This includes a Sludge Receipt and Adjustment Tank (SRAT) cycle, where acid is added to the sludge to destroy nitrite and remove mercury, and a Slurry Mix Evaporator (SME) cycle, where glass frit is added to the sludge in preparation for vitrification. The SME cycle also included replication of five canister decontamination additions and concentrations. Processing parameters for the CPC processing were based on work with a non radioactive simulant. (3) Vitrification of a portion of the SME product and Product Consistency Test (PCT) evaluation of the resulting glass. (4) Rheology measurements of the initial slurry samples and samples after each phase of CPC processing. This work is controlled by a Task Technical and Quality Assurance Plan (TTQAP) , and analyses are guided by an Analytical Study Plan. This work is Technical Baseline Research and Development (R&D) for the DWPF.

  20. Development of an IAEA Training Course for Future U.S. Inspectors

    SciTech Connect (OSTI)

    Savannah Avgerinos Fitzwater; Amanda R. Rynes; David S. Bracken; Richard R. M. Metcalf; James D. West

    2011-07-01

    U.S. citizens currently make up only 12% of the positions held in the IAEAs Department of Safeguards. While the United States has maintained a high level of support for the Agency over the duration of its history, the number of American inspectors currently in the field does not reflect this level of involvement. As a result, the National Nuclear Security Administrations Office of International Relations, as part of the Next Generation Safeguards Initiative (NGSI) mission, has tasked Idaho National Laboratory (INL) to develop a rigorous two week hands-on training program to encourage and operationally acclimatize U.S. Citizens who are interested in applying for IAEA inspector positions using IAEA authorized equipment at INL. Idaho National Laboratory is one-of-a-kind in its ability to train IAEA inspectors by including training at nuclear facilities on site and includes, for example, direct measurement of an active spent fuel storage cooling pond. This accredited course will introduce and train attendees on the major IAEA systems used in collecting nuclear safeguards data and performing safeguards inspections. Unique in the United States, these classes will give attendees direct hands-on training and will address equipment purpose, function, operating principles, application, and troubleshooting, based upon what would be expected of an IAEA Safeguards Inspector in the field and in the office. Upon completion, U.S. applicants will be better qualified to pursue a position in the IAEA Department of Safeguards Operational Divisions. In support, INL has recently established a new laboratory space to house state of the art nuclear safeguards instrumentation. Currently, equipment installed in the laboratory space includes attended systems: 3DLR (3-D Imaging Laser) for design information verification, a Digital Cerenkov Viewing Device for measurement of spent fuel, HM-5 handheld radiation detectors, quantitative neutron and gamma systems; unattended monitoring systems including: NGAM and MiniGRAND radiation systems and a DMOS camera system, and VACOSS/EOSS Optical Sealing Systems..

  1. Lignin-modifying enzymes of the white rot basidiomycete Ganoderma lucidum

    SciTech Connect (OSTI)

    D Merritt, C.S.; Reddy, C.A.

    1999-12-01

    Ganoderma lucidum, a white rot basidiomycete widely distributed worldwide, was studied for the production of the lignin-modifying enzymes laccase, manganese-dependent peroxidase (MnP), and lignin peroxidase (LiP). Laccase levels observed in high-nitrogen shaken cultures were much greater than those seen in low-nitrogen, malt extract, or wool-grown cultures and those reported for most other white rot fungi to date. Laccase production was readily seen in cultures grown with pine or poplar as the sole carbon and energy source. Cultures containing both pine and poplar showed 5- to 10-fold-higher levels of laccase than cultures containing pine or poplar alone. Since syringyl units are structural components important in poplar lignin and other hardwoods but much less so in pine lignin and other softwoods, pine cultures were supplemented with syringic acid, and this resulted in laccase levels comparable to those seen in pine-plus-poplar cultures. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of concentrated extracellular culture fluid from HM cultures showed two laccase activity bands, where as isoelectric focusing revealed five major laccase activity bands with estimated pIs of 3.0, 4.25, 4.5, and 5.1. Low levels of MnP activity were detected in poplar-grown cultures but not in cultures grown with pine, with pine plus syringic acid, or in HN medium. No LiP activity was seen in any of the media tested; however, probing the genomic DNA with the LiP cDNA (CLG4) from the white rot fungus Phanerochaete chrysosporium showed distinct hybridization bands suggesting the presence of lip-like sequences in G. lucidum.

  2. LOW-RESOLUTION SPECTROSCOPY OF GAMMA-RAY BURST OPTICAL AFTERGLOWS: BIASES IN THE SWIFT SAMPLE AND CHARACTERIZATION OF THE ABSORBERS

    SciTech Connect (OSTI)

    Fynbo, J. P. U.; Malesani, D.; Vreeswijk, P. M.; Hjorth, J.; Sollerman, J.; Thoene, C. C.; Jakobsson, P.; Bjoernsson, G.; De Cia, A.; Prochaska, J. X.; Nardini, M.; Chen, H.-W.; Bloom, J. S.; Castro-Tirado, A. J.; Gorosabel, J.; Christensen, L.; Fruchter, A. S.

    2009-12-01

    We present a sample of 77 optical afterglows (OAs) of Swift detected gamma-ray bursts (GRBs) for which spectroscopic follow-up observations have been secured. Our first objective is to measure the redshifts of the bursts. For the majority (90%) of the afterglows, the redshifts have been determined from the spectra. We provide line lists and equivalent widths (EWs) for all detected lines redward of Ly{alpha} covered by the spectra. In addition to the GRB absorption systems, these lists include line strengths for a total of 33 intervening absorption systems. We discuss to what extent the current sample of Swift bursts with OA spectroscopy is a biased subsample of all Swift detected GRBs. For that purpose we define an X-ray-selected statistical sample of Swift bursts with optimal conditions for ground-based follow-up from the period 2005 March to 2008 September; 146 bursts fulfill our sample criteria. We derive the redshift distribution for the statistical (X-ray selected) sample and conclude that less than 18% of Swift bursts can be at z > 7. We compare the high-energy properties (e.g., {gamma}-ray (15-350 keV) fluence and duration, X-ray flux, and excess absorption) for three subsamples of bursts in the statistical sample: (1) bursts with redshifts measured from OA spectroscopy; (2) bursts with detected optical and/or near-IR afterglow, but no afterglow-based redshift; and (3) bursts with no detection of the OA. The bursts in group (1) have slightly higher {gamma}-ray fluences and higher X-ray fluxes and significantly less excess X-ray absorption than bursts in the other two groups. In addition, the fractions of dark bursts, defined as bursts with an optical to X-ray slope {beta}{sub OX} < 0.5, is 14% in group (1), 38% in group (2), and >39% in group (3). For the full sample, the dark burst fraction is constrained to be in the range 25%-42%. From this we conclude that the sample of GRBs with OA spectroscopy is not representative for all Swift bursts, most likely due to a bias against the most dusty sight lines. This should be taken into account when determining, e.g., the redshift or metallicity distribution of GRBs and when using GRBs as a probe of star formation. Finally, we characterize GRB absorption systems as a class and compare them to QSO absorption systems, in particular the damped Ly{alpha} absorbers (DLAs). On average GRB absorbers are characterized by significantly stronger EWs for H I as well as for both low and high ionization metal lines than what is seen in intervening QSO absorbers. However, the distribution of line strengths is very broad and several GRB absorbers have lines with EWs well within the range spanned by QSO-DLAs. Based on the 33 z > 2 bursts in the sample, we place a 95% confidence upper limit of 7.5% on the mean escape fraction of ionizing photons from star-forming galaxies.

  3. Bringing simulation and observation together to better understand the intergalactic medium

    SciTech Connect (OSTI)

    Egan, Hilary; Smith, Britton D.; O'Shea, Brian W.; Shull, J. Michael

    2014-08-10

    The methods by which one characterizes the distribution of matter in cosmological simulations is intrinsically different from how one performs the same task observationally. In this paper, we make substantial steps toward comparing simulations and observations of the intergalactic medium (IGM) in a more sensible way. We present a pipeline that generates and fits synthetic QSO absorption spectra using sight lines cast through a cosmological simulation, and simultaneously identifies structure by directly analyzing the variations in H I and O VI number density. We compare synthetic absorption spectra with a less observationally motivated, but more straightforward density threshold-based method for finding absorbers. Our efforts focus on H I and O VI to better characterize the warm/hot IGM, a subset of the IGM that is challenging to conclusively identify observationally. We find that the two methods trace roughly the same quantities of H I and O VI above observable column density limits, but the synthetic spectra typically identify more substructure in absorbers. We use both methods to characterize H I and O VI absorber properties. We find that both integrated and differential column density distributions from both methods generally agree with observations. The distribution of Doppler parameters between the two methods are similar for Ly? and compare reasonably with observational results, but while the two methods agree with each other with O VI systems, they both are systematically different from observations. We find a strong correlation between O VI baryon fraction and O VI column density. We also discuss a possible bimodality in the temperature distribution of the gas traced by O VI.

  4. Imaging the heliosphere using neutral atoms from solar wind energy down to 15 eV

    SciTech Connect (OSTI)

    Galli, A.; Wurz, P.; Fuselier, S. A.; McComas, D. J.; Bzowski, M.; Sok?, J. M.; Kubiak, M. A.; Mbius, E.

    2014-11-20

    We study the spatial and temporal distribution of hydrogen energetic neutral atoms (ENAs) from the heliosheath observed with the IBEX-Lo sensor of the Interstellar Boundary EXplorer (IBEX) from solar wind energies down to the lowest available energy (15 eV). All available IBEX-Lo data from 2009 January until 2013 June were included. The sky regions imaged when the spacecraft was outside of Earth's magnetosphere and when the Earth was moving toward the direction of observation offer a sufficient signal-to-noise ratio even at very low energies. We find that the ENA ribbona 20 wide region of high ENA intensitiesis most prominent at solar wind energies whereas it fades at lower energies. The maximum emission in the ribbon is located near the poles for 2 keV and closer to the ecliptic plane for energies below 1 keV. This shift is an evidence that the ENA ribbon originates from the solar wind. Below 0.1 keV, the ribbon can no longer be identified against the globally distributed ENA signal. The ENA measurements in the downwind direction are affected by magnetospheric contamination below 0.5 keV, but a region of very low ENA intensities can be identified from 0.1 keV to 2 keV. The energy spectra of heliospheric ENAs follow a uniform power law down to 0.1 keV. Below this energy, they seem to become flatter, which is consistent with predictions. Due to the subtraction of local background, the ENA intensities measured with IBEX agree with the upper limit derived from Ly? observations.

  5. THE FIRST HIGH-REDSHIFT QUASAR FROM Pan-STARRS

    SciTech Connect (OSTI)

    Morganson, Eric; De Rosa, Gisella; Decarli, Roberto; Walter, Fabian; Rix, Hans-Walter; Chambers, Ken; Burgett, William; Flewelling, Heather; Hodapp, Klaus; Kaiser, Nick; Magnier, Eugene; Sweeney, Bill; Waters, Christopher; McGreer, Ian; Fan, Xiaohui; Greiner, Jochen; Price, Paul

    2012-06-15

    We present the discovery of the first high-redshift (z > 5.7) quasar from the Panoramic Survey Telescope and Rapid Response System 1 (Pan-STARRS1 or PS1). This quasar was initially detected as an i{sub P1} dropout in PS1, confirmed photometrically with the SAO Wide-field InfraRed Camera at Arizona's Multiple Mirror Telescope (MMT) and the Gamma-Ray Burst Optical/Near-Infrared Detector at the MPG 2.2 m telescope in La Silla. The quasar was verified spectroscopically with the MMT Spectrograph, Red Channel and the Cassegrain Twin Spectrograph at the Calar Alto 3.5 m telescope. Its near-infrared spectrum was taken at the Large Binocular Telescope Observatory (LBT) with the LBT Near-Infrared Spectroscopic Utility with Camera and Integral Field Unit for Extragalactic Research. It has a redshift of 5.73, an AB z{sub P1} magnitude of 19.4, a luminosity of 3.8 Multiplication-Sign 10{sup 47} erg s{sup -1}, and a black hole mass of 6.9 Multiplication-Sign 10{sup 9} M{sub Sun }. It is a broad absorption line quasar with a prominent Ly{beta} peak and a very blue continuum spectrum. This quasar is the first result from the PS1 high-redshift quasar search that is projected to discover more than 100 i{sub P1} dropout quasars and could potentially find more than 10 z{sub P1} dropout (z > 6.8) quasars.

  6. DES J0454–4448: Discovery of the first luminous z ≥ 6 quasar from the Dark Energy Survey

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

    Reed, S. L.

    2015-10-28

    We present the first results of a survey for high-redshift, z ≥ 6, quasars using izY multicolour photometric observations from the Dark Energy Survey (DES). Here we report the discovery and spectroscopic confirmation of the zAB, YAB = 20.2, 20.2 (M1450 = –26.5) quasar DES J0454–4448 with a redshift of z = 6.09±0.02 based on the onset of the Ly α forest and an H i near zone size of 4.1+1.1–1.2 proper Mpc. The quasar was selected as an i-band drop out with i–z = 2.46 and zAB < 21.5 from an area of ~300 deg2. It is the brightestmore » of our 43 candidates and was identified for spectroscopic follow-up solely based on the DES i–z and z–Y colours. The quasar is detected by WISE and has W1AB = 19.68. The discovery of one spectroscopically confirmed quasar with 5.7 < z < 6.5 and zAB ≤ 20.2 is consistent with recent determinations of the luminosity function at z ~ 6. DES when completed will have imaged ~5000 deg2 to YAB = 23.0 (5σ point source) and we expect to discover 50–100 new quasars with z > 6 including 3–10 with z > 7 dramatically increasing the numbers of quasars currently known that are suitable for detailed studies.« less

  7. The existence and nature of the interstellar bow shock

    SciTech Connect (OSTI)

    Ben-Jaffel, Lotfi; Strumik, M.; Ratkiewicz, R.; Grygorczuk, J.

    2013-12-20

    We report a new diagnosis of two different states of the local interstellar medium (LISM) near our solar system by using a sensitivity study constrained by several distinct and complementary observations of the LISM, solar wind, and inner heliosphere. Assuming the Interstellar Boundary Explorer (IBEX) He flow parameters for the LISM, we obtain a strength of ?2.7 0.2 ?G and a direction pointing away from galactic coordinates (28, 52) 3 for the interstellar magnetic field as a result of fitting Voyager 1 and Voyager 2 in situ plasma measurements and IBEX energetic neutral atoms ribbon. When using Ulysses parameters for the LISM He flow, we recently reported the same direction but with a strength of 2.2 0.1 ?G. First, we notice that with Ulysses He flow, our solution is in the expected hydrogen deflection plane (HDP). In contrast, for the IBEX He flow, the solution is ?20 away from the corresponding HDP plane. Second, the long-term monitoring of the interplanetary H I flow speed shows a value of ?26 km s{sup 1} measured upwind from the Doppler shift in the strong Ly? sky background emission line. All elements of the diagnosis seem therefore to support Ulysses He flow parameters for the interstellar state. In that frame, we argue that reliable discrimination between superfast, subfast, or superslow states of the interstellar flow should be based on most existing in situ and remote observations used together with global modeling of the heliosphere. For commonly accepted LISM ionization rates, we show that a fast interstellar bow shock should be standing off upstream of the heliopause.

  8. NGC 1365: A low column density state unveiling a low ionization disk wind

    SciTech Connect (OSTI)

    Braito, V.; Reeves, J. N.; Gofford, J.; Nardini, E.; Porquet, D.; Risaliti, G.

    2014-11-01

    We present the time-resolved spectral analysis of the XMM-Newton data of NGC 1365 collected during one XMM-Newton observation, which caught this 'changing-look' active galactic nucleus in a high flux state characterized also by a low column density (N {sub H} ? 10{sup 22} cm{sup 2}) of the X-ray absorber. During this observation, the low-energy photoelectric cut-off is at about ?1 keV and the primary continuum can be investigated with the XMM-Newton-RGS data, which show strong spectral variability that can be explained as a variable low N {sub H} that decreased from N {sub H} ? 10{sup 23} cm{sup 2} to 10{sup 22} cm{sup 2} in a 100 ks timescale. The spectral analysis of the last segment of the observation revealed the presence of several absorption features that can be associated with an ionized (log ? ? 2 erg cm s{sup 1}) outflowing wind (v {sub out} ? 2000 km s{sup 1}). We detected for the first time a possible P-Cygni profile of the Mg XII Ly? line associated with this mildly ionized absorber indicative of a wide angle outflowing wind. We suggest that this wind is a low ionization zone of the highly ionized wind present in NGC 1365, which is responsible for the iron K absorption lines and is located within the variable X-ray absorber. At the end of the observation, we detected a strong absorption line at E ? 0.76 keV most likely associated with a lower ionization zone of the absorber (log ? ? 0.2 erg cm s{sup 1}, N {sub H} ? 10{sup 22} cm{sup 2}), which suggests that the variable absorber in NGC 1365 could be a low ionization zone of the disk wind.

  9. THE SUBARU HIGH-z QUASAR SURVEY: DISCOVERY OF FAINT z ? 6 QUASARS

    SciTech Connect (OSTI)

    Kashikawa, Nobunari; Furusawa, Hisanori; Niino, Yuu [Optical and Infrared Astronomy Division, National Astronomical Observatory, Mitaka, Tokyo 181-8588 (Japan); Ishizaki, Yoshifumi; Onoue, Masafusa; Toshikawa, Jun; Ishikawa, Shogo [Department of Astronomy, School of Science, Graduate University for Advanced Studies, Mitaka, Tokyo 181-8588 (Japan); Willott, Chris J. [Herzberg Institute of Astrophysics, National Research Council, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Im, Myungshin [Center for the Exploration of the Origin of the Universe (CEOU), Astronomy Program, Department of Physics and Astronomy, Seoul National University, 1 Gwanak-rho, Gwanak-gu, Seoul 151-742 (Korea, Republic of); Shimasaku, Kazuhiro [Department of Astronomy, University of Tokyo, Hongo, Tokyo 113-0033 (Japan); Ouchi, Masami [Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8582 (Japan); Hibon, Pascale, E-mail: n.kashikawa@nao.ac.jp [Gemini Observatory, La Serena (Chile)

    2015-01-01

    We present the discovery of one or two extremely faint z ? 6 quasars in 6.5 deg{sup 2} utilizing a unique capability of the wide-field imaging of the Subaru/Suprime-Cam. The quasar selection was made in (i'-z{sub B} ) and (z{sub B} -z{sub R} ) colors, where z{sub B} and z{sub R} are bandpasses with central wavelengths of 8842 and 9841 , respectively. The color selection can effectively isolate quasars at z ? 6 from M/L/T dwarfs without the J-band photometry down to z{sub R} < 24.0, which is 3.5 mag deeper than the Sloan Digital Sky Survey (SDSS). We have selected 17 promising quasar candidates. The follow-up spectroscopy for seven targets identified one apparent quasar at z = 6.156 with M {sub 1450} = 23.10. We also identified one possible quasar at z = 6.041 with a faint continuum of M {sub 1450} = 22.58 and a narrow Ly? emission with HWHM =427 km s{sup 1}, which cannot be distinguished from Lyman ? emitters. We derive the quasar luminosity function at z ? 6 by combining our faint quasar sample with the bright quasar samples by SDSS and CFHQS. Including our data points invokes a higher number density in the faintest bin of the quasar luminosity function than the previous estimate employed. This suggests a steeper faint-end slope than lower z, though it is yet uncertain based on a small number of spectroscopically identified faint quasars, and several quasar candidates still remain to be diagnosed. The steepening of the quasar luminosity function at the faint end does increase the expected emission rate of the ionizing photon; however, it only changes by a factor of approximately two to six. This was found to still be insufficient for the required photon budget of reionization at z ? 6.

  10. Chemical constraints on the contribution of population III stars to cosmic reionization

    SciTech Connect (OSTI)

    Kulkarni, Girish; Hennawi, Joseph F. [Max Planck Institute for Astronomy, Knigstuhl 17, D-69117 Heidelberg (Germany); Rollinde, Emmanuel; Vangioni, Elisabeth, E-mail: girish@mpia-hd.mpg.de [Institut d'Astrophysique de Paris, UMR 7095, UPMC, Paris VI, 98 bis boulevard Arago, F-75014 Paris (France)

    2014-05-20

    Recent studies have highlighted that galaxies at z = 6-8 fall short of producing enough ionizing photons to reionize the intergalactic medium, and suggest that Population III stars could resolve this tension, because their harder spectra can produce ?10 more ionizing photons than Population II. We use a semi-analytic model of galaxy formation, which tracks galactic chemical evolution, to gauge the impact of Population III stars on reionization. Population III supernovae produce distinct metal abundances, and we argue that the duration of the Population III era can be constrained by precise relative abundance measurements in high-z damped Ly? absorbers (DLAs), which provide a chemical record of past star formation. We find that a single generation of Population III stars can self-enrich galaxies above the critical metallicity Z {sub crit} = 10{sup 4} Z {sub ?} for the Population III-to-II transition, on a very short timescale t {sub self-enrich} ? 10{sup 6} yr, owing to the large metal yields and short lifetimes of Population III stars. This subsequently terminates the Population III era, so they contribute ? 50% of the ionizing photons only for z ? 30, and at z = 10 contribute <1%. The Population III contribution can be increased by delaying metal mixing into the interstellar medium. However, comparing the resulting metal abundance pattern to existing measurements in z ? 6 DLAs, we show that the observed [O/Si] ratios of absorbers rule out Population III stars being a major contributor to reionization. Future abundance measurements of z ? 7-8 QSOs and gamma-ray bursts should probe the era when the chemical vestiges of Population III star formation become detectable.

  11. The OH rotational population and photodissociation of H{sub 2}O in DG Tauri

    SciTech Connect (OSTI)

    Carr, John S.; Najita, Joan R.

    2014-06-10

    We analyze the OH rotational emission in the Spitzer Space Telescope mid-infrared spectrum of the T Tauri star DG Tau. OH is observed in emission from upper level energies of 1900 K to 28,000 K. The rotational diagram cannot be fit with any single combination of temperature and column density and has slopes that correspond to excitation temperatures ranging from 200 K to 6000 K. The relative ?-doublet population within each rotational level is not equal, showing that the OH population is not in thermal equilibrium. The symmetric ?-doublet state is preferred in all rotational states, with an average of 0.5 for the population ratio of the anti-symmetric to symmetric state. We show that the population distribution of the high rotational lines and the ?-doublet ratio are consistent with the formation of OH following the photo-dissociation of H{sub 2}O by FUV photons in the second absorption band of water (?1150-1400 ), which includes Ly?. Other processes, OH formation from either photo-dissociation of water in the first absorption band (1450-1900 ) or the reaction O({sup 1} D) + H{sub 2}, or collisional excitation, cannot explain the observed emission in the high rotational states but could potentially contribute to the population of lower rotational levels. These results demonstrate that the photodissociation of water is active in DG Tau and support the idea that the hot rotational OH emission commonly observed in Classical T Tauri stars is due to the dissociation of H{sub 2}O by FUV radiation.

  12. COS OBSERVATIONS OF METAL LINE AND BROAD LYMAN-{alpha} ABSORPTION IN THE MULTI-PHASE O VI AND Ne VIII SYSTEM AT z = 0.20701 TOWARD HE 0226-4110

    SciTech Connect (OSTI)

    Savage, B. D. [Department of Astronomy, University of Wisconsin-Madison, 475 North Charter Street, Madison, WI 53706 (United States); Lehner, N. [Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46556 (United States); Narayanan, A. [Indian Institute of Space Science and Technology, Thiruvananthapuram 695547, Kerala (India)

    2011-12-20

    Observations of the QSO HE 0226-4110 (z{sub em} = 0.495) with the Cosmic Origins Spectrograph (COS) from 1134 to 1796 A with a resolution of {approx}17 km s{sup -1} and signal-to-noise ratio (S/N) per resolution element of 20-40 are used to study the multi-phase absorption system at z = 0.20701 containing O VI and Ne VIII. The system was previously studied with lower S/N observations with Far-Ultraviolet Spectroscopic Explorer (FUSE) and Space Telescope Imaging Spectrograph (STIS). The COS observations provide more reliable measures of the H I and metal lines present in the system and reveal the clear presence of broad Ly{alpha} (BLA) absorption with b = 72(+13, -6) km s{sup -1} and log N(H I) = 13.87 {+-} 0.08. Detecting BLAs associated with warm gas absorbers is crucial for determining the temperature, metallicity, and total baryonic content of the absorbers. The BLA is probably recording the trace amount of thermally broadened H I in the collisionally ionized plasma with log T {approx} 5.7 that also produces the O VI and Ne VIII absorption. The total hydrogen column in the collisionally ionized gas, log N(H) {approx} 20.1, exceeds that in the cooler photoionized gas in the system by a factor of {approx}22. The oxygen abundance in the collisionally ionized gas is [O/H] = -0.89 {+-} 0.08 {+-} 0.07. The absorber probably occurs in the circumgalactic environment (halo) of a foreground L = 0.25L{sub *} disk galaxy with an impact parameter of 109 h{sub 70}{sup -1} kpc identified by Mulchaey and Chen.

  13. THE COSMIC ORIGINS SPECTROGRAPH

    SciTech Connect (OSTI)

    Green, James C.; Michael Shull, J.; Snow, Theodore P.; Stocke, John [Department of Astrophysical and Planetary Sciences, University of Colorado, 391-UCB, Boulder, CO 80309 (United States); Froning, Cynthia S.; Osterman, Steve; Beland, Stephane; Burgh, Eric B.; Danforth, Charles; France, Kevin [Center for Astrophysics and Space Astronomy, University of Colorado, 389-UCB, Boulder, CO 80309 (United States); Ebbets, Dennis [Ball Aerospace and Technologies Corp., 1600 Commerce Street, Boulder, CO 80301 (United States); Heap, Sara H. [NASA Goddard Space Flight Center, Code 681, Greenbelt, MD 20771 (United States); Leitherer, Claus; Sembach, Kenneth [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Linsky, Jeffrey L. [JILA, University of Colorado and NIST, Boulder, CO 80309-0440 (United States); Savage, Blair D. [Department of Astronomy, University of Wisconsin-Madison, 475 North Charter Street, Madison, WI 53706 (United States); Siegmund, Oswald H. W. [Astronomy Department, University of California, Berkeley, CA 94720 (United States); Spencer, John; Alan Stern, S. [Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302 (United States); Welsh, Barry [Space Sciences Laboratory, University of California, 7 Gauss Way, Berkeley, CA 94720 (United States); and others

    2012-01-01

    The Cosmic Origins Spectrograph (COS) is a moderate-resolution spectrograph with unprecedented sensitivity that was installed into the Hubble Space Telescope (HST) in 2009 May, during HST Servicing Mission 4 (STS-125). We present the design philosophy and summarize the key characteristics of the instrument that will be of interest to potential observers. For faint targets, with flux F{sub {lambda}} Almost-Equal-To 1.0 Multiplication-Sign 10{sup -14} erg cm{sup -2} s{sup -1} A{sup -1}, COS can achieve comparable signal to noise (when compared to Space Telescope Imaging Spectrograph echelle modes) in 1%-2% of the observing time. This has led to a significant increase in the total data volume and data quality available to the community. For example, in the first 20 months of science operation (2009 September-2011 June) the cumulative redshift pathlength of extragalactic sight lines sampled by COS is nine times than sampled at moderate resolution in 19 previous years of Hubble observations. COS programs have observed 214 distinct lines of sight suitable for study of the intergalactic medium as of 2011 June. COS has measured, for the first time with high reliability, broad Ly{alpha} absorbers and Ne VIII in the intergalactic medium, and observed the He II reionization epoch along multiple sightlines. COS has detected the first CO emission and absorption in the UV spectra of low-mass circumstellar disks at the epoch of giant planet formation, and detected multiple ionization states of metals in extra-solar planetary atmospheres. In the coming years, COS will continue its census of intergalactic gas, probe galactic and cosmic structure, and explore physics in our solar system and Galaxy.

  14. CHARACTERIZING THE CIRCUMGALACTIC MEDIUM OF NEARBY GALAXIES WITH HST/COS AND HST/STIS ABSORPTION-LINE SPECTROSCOPY

    SciTech Connect (OSTI)

    Stocke, John T.; Keeney, Brian A.; Danforth, Charles W.; Shull, J. Michael; Froning, Cynthia S.; Green, James C.; Penton, Steven V. [Center for Astrophysics and Space Astronomy, Department of Astrophysical and Planetary Sciences, University of Colorado, 389 UCB, Boulder, CO 80309 (United States)] [Center for Astrophysics and Space Astronomy, Department of Astrophysical and Planetary Sciences, University of Colorado, 389 UCB, Boulder, CO 80309 (United States); Savage, Blair D., E-mail: john.stocke@colorado.edu [Department of Astronomy, University of Wisconsin, Madison, WI 53706 (United States)

    2013-02-15

    The circumgalactic medium (CGM) of late-type galaxies is characterized using UV spectroscopy of 11 targeted QSO/galaxy pairs at z {<=} 0.02 with the Hubble Space Telescope Cosmic Origins Spectrograph (COS) and {approx}60 serendipitous absorber/galaxy pairs at z {<=} 0.2 with the Space Telescope Imaging Spectrograph. CGM warm cloud properties are derived, including volume filling factors of 3%-5%, cloud sizes of 0.1-30 kpc, masses of 10-10{sup 8} M {sub Sun }, and metallicities of {approx}0.1-1 Z {sub Sun }. Almost all warm CGM clouds within 0.5 R {sub vir} are metal-bearing and many have velocities consistent with being bound, 'galactic fountain' clouds. For galaxies with L {approx}> 0.1 L*, the total mass in these warm CGM clouds approaches 10{sup 10} M {sub Sun }, {approx}10%-15% of the total baryons in massive spirals and comparable to the baryons in their parent galaxy disks. This leaves {approx}> 50% of massive spiral-galaxy baryons 'missing'. Dwarfs (<0.1 L*) have smaller area covering factors and warm CGM masses ({<=}5% baryon fraction), suggesting that many of their warm clouds escape. Constant warm cloud internal pressures as a function of impact parameter (P/k {approx} 10 cm{sup -3} K) support the inference that previous COS detections of broad, shallow O VI and Ly{alpha} absorptions are of an extensive ({approx}400-600 kpc), hot (T Almost-Equal-To 10{sup 6} K), intra-cloud gas which is very massive ({>=}10{sup 11} M {sub Sun }). While the warm CGM clouds cannot account for all the 'missing baryons' in spirals, the hot intra-group gas can, and could account for {approx}20% of the cosmic baryon census at z {approx} 0 if this hot gas is ubiquitous among spiral groups.

  15. HST-COS observations of AGNs. II. Extended survey of ultraviolet composite spectra from 159 active galactic nuclei

    SciTech Connect (OSTI)

    Stevans, Matthew L. [Present address: Astronomy Department, University of Texas, Austin, TX 78712, USA. (United States); Shull, J. Michael [Also at Institute of Astronomy, Cambridge University, Cambridge CB3 OHA, UK. (United Kingdom); Danforth, Charles W.; Tilton, Evan M., E-mail: stevans@astro.as.utexas.edu, E-mail: michael.shull@colorado.edu, E-mail: charles.danforth@colorado.edu, E-mail: evan.tilton@colorado.edu [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309 (United States)

    2014-10-10

    The ionizing fluxes from quasars and other active galactic nuclei (AGNs) are critical for interpreting their emission-line spectra and for photoionizing and heating the intergalactic medium. Using far-ultraviolet (FUV) spectra from the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST), we directly measure the rest-frame ionizing continua and emission lines for 159 AGNs at redshifts 0.001 < z {sub AGN} < 1.476 and construct a composite spectrum from 475 to 1875 . We identify the underlying AGN continuum and strong extreme ultraviolet (EUV) emission lines from ions of oxygen, neon, and nitrogen after masking out absorption lines from the H I Ly? forest, 7 Lyman-limit systems (N{sub H} {sub I}?10{sup 17.2} cm{sup 2}) and 214 partial Lyman-limit systems (14.5

  16. THE IMPACT OF STARBURSTS ON THE CIRCUMGALACTIC MEDIUM

    SciTech Connect (OSTI)

    Borthakur, Sanchayeeta; Heckman, Timothy; Strickland, David [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Wild, Vivienne [School of Physics and Astronomy, University of St. Andrews, St. Andrews, Fife, KY16 95S (United Kingdom); Scottish Universities Physics Alliance (SUPA) (United Kingdom); Schiminovich, David, E-mail: sanch@pha.jhu.edu [Department of Astronomy, Columbia University, New York, NY 10027 (United States)

    2013-05-01

    We present a study exploring the impact of a starburst on the properties of the surrounding circumgalactic medium (CGM): gas located beyond the galaxy's stellar body and extending out to the virial radius ({approx}200 kpc). We obtained ultraviolet spectroscopic data from the Cosmic Origins Spectrograph (COS) probing the CGM of 20 low-redshift foreground galaxies using background QSOs. Our sample consists of starburst and control galaxies. The latter comprises normal star-forming and passive galaxies with similar stellar masses and impact parameters as the starbursts. We used optical spectra from the Sloan Digital Sky Survey to estimate the properties of the starbursts, inferring average ages of {approx}200 Myr and burst fractions involving {approx}10% of their stellar mass. The COS data reveal highly ionized gas traced by C IV in 80%(4/5) of the starburst and in 17%(2/12) of the control sample. The two control galaxies with C IV absorbers differed from the four starbursts in showing multiple low-ionization transitions and strong saturated Ly{alpha} lines. They therefore appear to be physically different systems. We show that the C IV absorbers in the starburst CGM represent a significant baryon repository. The high detection rate of this highly ionized material in the starbursts suggests that starburst-driven winds can affect the CGM out to radii as large as 200 kpc. This is plausible given the inferred properties of the starbursts and the known properties of starburst-driven winds. This would represent the first direct observational evidence of local starbursts impacting the bulk of their gaseous halos, and as such provides new evidence of the importance of this kind of feedback in the evolution of galaxies.

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

    SciTech Connect (OSTI)

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

    2013-11-01

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

  18. HST-COS OBSERVATIONS OF AGNs. I. ULTRAVIOLET COMPOSITE SPECTRA OF THE IONIZING CONTINUUM AND EMISSION LINES

    SciTech Connect (OSTI)

    Shull, J. Michael; Stevans, Matthew; Danforth, Charles W., E-mail: michael.shull@colorado.edu, E-mail: matthew.stevans@colorado.edu, E-mail: charles.danforth@colorado.edu [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309 (United States)

    2012-06-20

    The ionizing fluxes from quasars and other active galactic nuclei (AGNs) are critical for interpreting the emission-line spectra of AGNs and for photoionization and heating of the intergalactic medium. Using ultraviolet spectra from the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST), we have directly measured the rest-frame ionizing continua and emission lines for 22 AGNs. Over the redshift range 0.026 < z < 1.44, COS samples the Lyman continuum and many far-UV emission lines (Ly{alpha} {lambda}1216, C IV {lambda}1549, Si IV/O IV] {lambda}1400, N V {lambda}1240, O VI {lambda}1035). Strong EUV emission lines with 14-22 eV excitation energies (Ne VIII {lambda}{lambda}770, 780, Ne V {lambda}569, O II {lambda}834, O III {lambda}833, {lambda}702, O IV {lambda}788, 608, 554, O V {lambda}630, N III {lambda}685) suggest the presence of hot gas in the broad emission-line region. The rest-frame continuum, F{sub {nu}}{proportional_to}{nu}{sup {alpha}{sub {nu}}}, shows a break at wavelengths {lambda} < 1000 A, with spectral index {alpha}{sub {nu}} = -0.68 {+-} 0.14 in the FUV (1200-2000 A) steepening to {alpha}{sub {nu}} = -1.41 {+-} 0.21 in the EUV (500-1000 A). The COS EUV index is similar to that of radio-quiet AGNs in the 2002 HST/FOS survey ({alpha}{sub {nu}} = -1.57 {+-} 0.17). We see no Lyman edge ({tau}{sub HI} < 0.03) or He I {lambda}584 emission in the AGN composite. Our 22 AGNs exhibit a substantial range of FUV/EUV spectral indices and a correlation with AGN luminosity and redshift, likely due to observing below the 1000 A spectral break.

  19. Absorption-line detections of 10{sup 5}-10{sup 6} K gas in spiral-rich groups of galaxies

    SciTech Connect (OSTI)

    Stocke, John T.; Keeney, Brian A.; Danforth, Charles W.; Syphers, David; Yamamoto, H.; Shull, J. Michael; Green, James C.; Froning, Cynthia [Center for Astrophysics and Space Astronomy, Department of Astrophysical and Planetary Sciences, University of Colorado, 389 UCB, Boulder, CO 80309 (United States); Savage, Blair D.; Wakker, Bart; Kim, Tae-Sun [Department of Astronomy, University of Wisconsin, Madison, WI 53706 (United States); Ryan-Weber, Emma V.; Kacprzak, Glenn G., E-mail: john.stocke@colorado.edu [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, VIC 3122 (Australia)

    2014-08-20

    Using the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope, the COS Science Team has conducted a high signal-to-noise survey of 14 bright QSOs. In a previous paper, these far-UV spectra were used to discover 14 'warm' (T ? 10{sup 5} K) absorbers using a combination of broad Ly? and broad O VI absorptions. A reanalysis of a few of this new class of absorbers using slightly relaxed fitting criteria finds as many as 20 warm absorbers could be present in this sample. A shallow, wide spectroscopic galaxy redshift survey has been conducted around these sight lines to investigate the warm absorber environment, which is found to be spiral-rich groups or cluster outskirts with radial velocity dispersions ? = 250-750 km s{sup 1}. While 2? evidence is presented favoring the hypothesis that these absorptions are associated with the galaxy groups and not with the individual, nearest galaxies, this evidence has considerable systematic uncertainties and is based on a small sample size so it is not entirely conclusive. If the associations are with galaxy groups, the observed frequency of warm absorbers (dN/dz = 3.5-5 per unit redshift) requires them to be very extended as an ensemble on the sky (?1 Mpc in radius at high covering factor). Most likely these warm absorbers are interface gas clouds whose presence implies the existence of a hotter (T ? 10{sup 6.5} K), diffuse, and probably very massive (>10{sup 11} M {sub ?}) intra-group medium which has yet to be detected directly.

  20. DISCOVERY OF A STRONG LENSING GALAXY EMBEDDED IN A CLUSTER AT z = 1.62

    SciTech Connect (OSTI)

    Wong, Kenneth C.; Suyu, Sherry H.; Tran, Kim-Vy H.; Papovich, Casey J.; Momcheva, Ivelina G.; Brammer, Gabriel B.; Koekemoer, Anton M.; Brodwin, Mark; Gonzalez, Anthony H.; Kacprzak, Glenn G.; Rudnick, Gregory H.; Halkola, Aleksi

    2014-07-10

    We identify a strong lensing galaxy in the cluster IRC 0218 (also known as XMM-LSS J0218205102) that is spectroscopically confirmed to be at z = 1.62, making it the highest-redshift strong lens galaxy known. The lens is one of the two brightest cluster galaxies and lenses a background source galaxy into an arc and a counterimage. With Hubble Space Telescope (HST) grism and Keck/LRIS spectroscopy, we measure the source redshift to be z {sub S} = 2.26. Using HST imaging in ACS/F475W, ACS/F814W, WFC3/F125W, and WFC3/F160W, we model the lens mass distribution with an elliptical power-law profile and account for the effects of the cluster halo and nearby galaxies. The Einstein radius is ?{sub E}=0.38{sub ?0.01}{sup +0.02} arcsec (3.2{sub ?0.1}{sup +0.2} kpc) and the total enclosed mass is M {sub tot}(Ly? and [O III] are likely to probe different regions in the source.

  1. NIR SPECTROSCOPIC OBSERVATION OF MASSIVE GALAXIES IN THE PROTOCLUSTER AT z = 3.09

    SciTech Connect (OSTI)

    Kubo, Mariko; Yamada, Toru; Ichikawa, Takashi; Kajisawa, Masaru; Matsuda, Yuichi; Tanaka, Ichi

    2015-01-20

    We present the results of near-infrared spectroscopic observations of the K-band-selected candidate galaxies in the protocluster at z = 3.09 in the SSA22 field. We observed 67 candidates with K {sub AB} < 24 and confirmed redshifts of the 39 galaxies at 2.0 < z {sub spec} < 3.4. Of the 67 candidates, 24 are certainly protocluster members with 3.04 ? z {sub spec} ? 3.12, which are massive red galaxies that have been unidentified in previous optical observations of the SSA22 protocluster. Many distant red galaxies (J K {sub AB} > 1.4), hyper extremely red objects (J K {sub AB} > 2.1), Spitzer MIPS 24 ?m sources, active galactic nuclei (AGNs) as well as the counterparts of Ly? blobs and the AzTEC/ASTE 1.1 mm sources in the SSA22 field are also found to be protocluster members. The mass of the SSA22 protocluster is estimated to be ?2-5 10{sup 14} M {sub ?}, and this system is plausibly a progenitor of the most massive clusters of galaxies in the current universe. The reddest (J K {sub AB} ? 2.4) protocluster galaxies are massive galaxies with M {sub star} ? 10{sup 11} M {sub ?} showing quiescent star formation activities and plausibly dominated by old stellar populations. Most of these massive quiescent galaxies host moderately luminous AGNs detected by X-ray. There are no significant differences in the [O III] ?5007/H? emission line ratios and [O III] ?5007 line widths and spatial extents of the protocluster galaxies from those of massive galaxies at z ? 2-3 in the general field.

  2. Overexpression of SnoN/SkiL, amplified at the 3q26.2 locus, in ovarian cancers: A role in ovarian pathogenesis

    SciTech Connect (OSTI)

    Nanjundan, Meera; Cheng, Kwai Wa; Zhang, Fan; Lahad, John; Kuo, Wen-Lin; Schmandt, Rosemarie; Smith-McCune, Karen; Fishman, David; Gray, Joe W.; Mills, Gordon B.

    2008-07-18

    High-resolution array comparative genomic hybridization of 235 serous epithelial ovarian cancers demonstrated a regional increase at 3q26.2 encompassing SnoN/SkiL, a coregulator of SMAD/TGF{beta} signaling. SnoN RNA transcripts were elevated in {approx}80% of advanced stage serous epithelial ovarian cancers. In both immortalized normal (TIOSE) and ovarian carcinoma cell lines (OVCA), SnoN RNA levels were increased by TGF{beta} stimulation and altered by LY294002 and JNK II inhibitor treatment suggesting that the PI3K and JNK signaling pathways may regulate TGF{beta}-induced increases in SnoN RNA. In TIOSE, SnoN protein levels were reduced 15min post TGF{beta}-stimulation, likely by proteosome-mediated degradation. In contrast, in OVCA, SnoN levels were elevated 3h post-stimulation potentially as a result of inhibition of the proteosome. To elucidate the role of SnoN in ovarian tumorigenesis, we explored the effects of both increasing and decreasing SnoN levels. In both TIOSE and OVCA, SnoN siRNA decreased cell growth between 20 and 50% concurrent with increased p21 levels. In TIOSE, transient expression of SnoN repressed TGF{beta} induction of PAI-1 promoters with little effect on the p21 promoter or resultant cell growth. In contrast to the effects of transient expression, stable expression of SnoN in TIOSE led to growth arrest through induction of senescence. Collectively, these results implicate SnoN levels in multiple roles during ovarian carcinogenesis: promoting cellular proliferation in ovarian cancer cells and as a positive mediator of cell cycle arrest and senescence in non-transformed ovarian epithelial cells.

  3. THE MULTI-OBJECT, FIBER-FED SPECTROGRAPHS FOR THE SLOAN DIGITAL SKY SURVEY AND THE BARYON OSCILLATION SPECTROSCOPIC SURVEY

    SciTech Connect (OSTI)

    Smee, Stephen A.; Barkhouser, Robert H.; Gunn, James E.; Carr, Michael A.; Lupton, Robert H.; Loomis, Craig; Uomoto, Alan; Roe, Natalie; Schlegel, David; Rockosi, Constance M.; Leger, French; Owen, Russell; Anderson, Lauren; Dawson, Kyle S.; Olmstead, Matthew D.; Brinkmann, Jon; Long, Dan; Honscheid, Klaus; Harding, Paul; Annis, James; and others

    2013-08-01

    We present the design and performance of the multi-object fiber spectrographs for the Sloan Digital Sky Survey (SDSS) and their upgrade for the Baryon Oscillation Spectroscopic Survey (BOSS). Originally commissioned in Fall 1999 on the 2.5 m aperture Sloan Telescope at Apache Point Observatory, the spectrographs produced more than 1.5 million spectra for the SDSS and SDSS-II surveys, enabling a wide variety of Galactic and extra-galactic science including the first observation of baryon acoustic oscillations in 2005. The spectrographs were upgraded in 2009 and are currently in use for BOSS, the flagship survey of the third-generation SDSS-III project. BOSS will measure redshifts of 1.35 million massive galaxies to redshift 0.7 and Ly{alpha} absorption of 160,000 high redshift quasars over 10,000 deg{sup 2} of sky, making percent level measurements of the absolute cosmic distance scale of the universe and placing tight constraints on the equation of state of dark energy. The twin multi-object fiber spectrographs utilize a simple optical layout with reflective collimators, gratings, all-refractive cameras, and state-of-the-art CCD detectors to produce hundreds of spectra simultaneously in two channels over a bandpass covering the near-ultraviolet to the near-infrared, with a resolving power R = {lambda}/FWHM {approx} 2000. Building on proven heritage, the spectrographs were upgraded for BOSS with volume-phase holographic gratings and modern CCD detectors, improving the peak throughput by nearly a factor of two, extending the bandpass to cover 360 nm < {lambda} < 1000 nm, and increasing the number of fibers from 640 to 1000 per exposure. In this paper we describe the original SDSS spectrograph design and the upgrades implemented for BOSS, and document the predicted and measured performances.

  4. The O VII X-Ray Forest Toward Markarian 421: Consistency between XMM-Newton and Chandra

    SciTech Connect (OSTI)

    Kaastra, J.S.; Werner, N.; Herder, J.W.A.den; /SRON, Utrecht; Paerels, F.B.S.; /Columbia U., Astron. Astrophys.; de Plaa, J.; /SRON, Utrecht; Rasmussen, A.P.; /KIPAC, Menlo; de Vries, C.P.; /SRON, Utrecht

    2006-04-28

    Recently the first detections of highly ionized gas associated with two Warm-Hot Intergalactic Medium (WHIM) filaments have been reported. The evidence is based on X-ray absorption lines due to O VII and other ions observed by Chandra towards the bright blazar Mrk 421. We investigate the robustness of this detection by a re-analysis of the original Chandra LETGS spectra, the analysis of a large set of XMM-Newton RGS spectra of Mrk 421, and additional Chandra observations. We address the reliability of individual spectral features belonging to the absorption components, and assess the significance of the detection of these components. We also use Monte Carlo simulations of spectra. We confirm the apparent strength of several features in the Chandra spectra, but demonstrate that they are statistically not significant. This decreased significance is due to the number of redshift trials that are made and that are not taken into account in the original discovery paper. Therefore these features must be attributed to statistical fluctuations. This is confirmed by the RGS spectra, which have a higher signal to noise ratio than the Chandra spectra, but do not show features at the same wavelengths. Finally, we show that the possible association with a Ly{alpha} absorption system also lacks sufficient statistical evidence. We conclude that there is insufficient observational proof for the existence of the two proposed WHIM filaments towards Mrk 421, the brightest X-ray blazar on the sky. Therefore, the highly ionized component of the WHIM still remains to be discovered.

  5. WATER PRODUCTION IN COMETS 2001 Q4 (NEAT) AND 2002 T7 (LINEAR) DETERMINED FROM SOHO/SWAN OBSERVATIONS

    SciTech Connect (OSTI)

    Combi, M. R.; Lee, Y.; Maekinen, J. T. T.; Bertaux, J.-L.; Quemerais, E.

    2009-06-15

    The SWAN all-sky camera on the Solar and Heliospheric Observatory (SOHO) spacecraft detected the hydrogen Lyman-alpha (Ly{alpha}) comae of comets 2001 Q4 NEAT and 2002 T7 LINEAR for large portions of their perihelion apparitions in 2003 and 2004. C/2001 Q4 NEAT was observed from 2003 September 14 through 2004 November 2, covering heliocentric distances from 3.23 AU before perihelion to 2.75 AU after, and C/2002 T7 LINEAR was observed from 2003 December 4 through 2004 August 6, covering heliocentric distances from 2.52 AU before perihelion to 2.09 AU after. We combined the full set of comet specific and full-sky observations and used our time-resolved model (TRM), which enables us to extract continuous values of the daily-average value of the water production rate throughout most of this entire period. The average power-law fit to the production rate variation of C/2001 Q4 NEAT with heliocentric distance, r, gives 3.5 x 10{sup 29} r {sup -1.7} and that for C/2002 T7 LINEAR gives 4.6 x 10{sup 29} r {sup -2.0}. Both comets show roughly a factor of 2 asymmetry in activity about perihelion, being more active before perihelion. C/2001 Q4 NEAT showed a production rate outburst about 30 days before perihelion (2004 April 15) and then a large extended increase above the nominal trend from 50 to 70 days after perihelion (2004 July 5-July 25)

  6. SOLAR RADIATION PRESSURE AND LOCAL INTERSTELLAR MEDIUM FLOW PARAMETERS FROM INTERSTELLAR BOUNDARY EXPLORER LOW ENERGY HYDROGEN MEASUREMENTS

    SciTech Connect (OSTI)

    Schwadron, N. A.; Moebius, E.; Kucharek, H.; Lee, M. A.; French, J.; Saul, L.; Wurz, P.; Bzowski, M.; Fuselier, S. A.; Livadiotis, G.; McComas, D. J.; Frisch, P.; Gruntman, M.; Mueller, H. R.

    2013-10-01

    Neutral hydrogen atoms that travel into the heliosphere from the local interstellar medium (LISM) experience strong effects due to charge exchange and radiation pressure from resonant absorption and re-emission of Ly?. The radiation pressure roughly compensates for the solar gravity. As a result, interstellar hydrogen atoms move along trajectories that are quite different than those of heavier interstellar species such as helium and oxygen, which experience relatively weak radiation pressure. Charge exchange leads to the loss of primary neutrals from the LISM and the addition of new secondary neutrals from the heliosheath. IBEX observations show clear effects of radiation pressure in a large longitudinal shift in the peak of interstellar hydrogen compared with that of interstellar helium. Here, we compare results from the Lee et al. interstellar neutral model with IBEX-Lo hydrogen observations to describe the distribution of hydrogen near 1 AU and provide new estimates of the solar radiation pressure. We find over the period analyzed from 2009 to 2011 that radiation pressure divided by the gravitational force (?) has increased slightly from ? = 0.94 0.04 in 2009 to ? = 1.01 0.05 in 2011. We have also derived the speed, temperature, source longitude, and latitude of the neutral H atoms and find that these parameters are roughly consistent with those of interstellar He, particularly when considering the filtration effects that act on H in the outer heliosheath. Thus, our analysis shows that over the period from 2009 to 2011, we observe signatures of neutral H consistent with the primary distribution of atoms from the LISM and a radiation pressure that increases in the early rise of solar activity.

  7. Analyzing Losses: Transuranics into Waste and Fission Products into Recycled Fuel

    SciTech Connect (OSTI)

    Steven J. Piet; Nick R. Soelberg; Samuel E. Bays; Robert E. Cherry; Layne F. Pincock; Eric L. Shaber; Melissa C. Teague; Gregory M. Teske; Kurt G. Vedros; Candido Pereira; Denia Djokic

    2010-11-01

    All mass streams from separations and fuel fabrication are products that must meet criteria. Those headed for disposal must meet waste acceptance criteria (WAC) for the eventual disposal sites corresponding to their waste classification. Those headed for reuse must meet fuel or target impurity limits. A loss is any material that ends up where it is undesired. The various types of losses are linked in the sense that as the loss of transuranic (TRU) material into waste is reduced, often the loss or carryover of waste into TRU or uranium is increased. We have analyzed four separation options and two fuel fabrication options in a generic fuel cycle. The separation options are aqueous uranium extraction plus (UREX+1), electrochemical, Atomics International reduction oxidation separation (AIROX), and melt refining. UREX+1 and electrochemical are traditional, full separation techniques. AIROX and melt refining are taken as examples of limited separations, also known as minimum fuel treatment. The fuels are oxide and metal. To define a generic fuel cycle, a fuel recycling loop is fed from used light water reactor (LWR) uranium oxide fuel (UOX) at 51 MWth-day/kg-iHM burnup. The recycling loop uses a fast reactor with TRU conversion ratio (CR) of 0.50. Excess recovered uranium is put into storage. Only waste, not used fuel, is disposed unless the impurities accumulate to a level so that it is impossible to make new fuel for the fast reactor. Impurities accumulate as dictated by separation removal and fission product generation. Our model approximates adjustment to fast reactor fuel stream blending of TRU and U products from incoming LWR UOX and recycling FR fuel to compensate for impurity accumulation by adjusting TRU:U ratios. Our mass flow model ignores postulated fuel impurity limits; we compare the calculated impurity values with those limits to identify elements of concern. AIROX and melt refining cannot be used to separate used LWR UOX-51 because they cannot separate U from TRU, it is then impossible to make X% TRU for fast reactors with UOX-51 used fuel with 1.3% TRU. AIROX and melt refining can serve in the recycle loop for about 3 recycles, at which point the accumulated impurities displace fertile uranium and the fuel can no longer be as critical as the original fast reactor fuel recipe. UREX+1 and electrochemical can serve in either capacity; key impurities appear to be lanthanides and several transition metals.

  8. Disorder dependent half-metallicity in Mn{sub 2}CoSi inverse Heusler alloy

    SciTech Connect (OSTI)

    Singh, Mukhtiyar; Saini, Hardev S.; Thakur, Jyoti; Reshak, Ali H.; Kashyap, Manish K.

    2013-12-15

    Heusler alloys based thin-films often exhibit a degree of atomic disorder which leads to the lowering of spin polarization in spintronic devices. We present ab-initio calculations of atomic disorder effects on spin polarization and half-metallicity of Mn{sub 2}CoSi inverse Heusler alloy. The five types of disorder in Mn{sub 2}CoSi have been proposed and investigated in detail. The A2{sub a}-type and B2-type disorders destroy the half-metallicity whereas it sustains for all disorders concentrations in DO{sub 3a}- and A2{sub b}-type disorder and for smallest disorder concentration studied in DO{sub 3b}-type disorder. Lower formation energy/atom for A2{sub b}-type disorder than other four disorders in Mn{sub 2}CoSi advocates the stability of this disorder. The total magnetic moment shows a strong dependence on the disorder and the change in chemical environment. The 100% spin polarization even in the presence of disorders explicitly supports that these disorders shall not hinder the use of Mn{sub 2}CoSi inverse Heusler alloy in device applications. - Graphical abstract: Minority-spin gap (E{sub g↓}) and HM gap (E{sub sf}) as a function of concentrations of various possible disorder in Mn{sub 2}CoSi inverse Heusler alloy. The squares with solid line (black color)/dotted line (blue color)/dashed line (red color) reperesents E{sub g↓} for DO{sub 3a}-/DO{sub 3b}-/A2{sub b}-type disorder in Mn{sub 2}CoSi and the spheres with solid line (black color)/dottedline (blue color)/dashed line (red color) represents E{sub sf} for DO{sub 3a}-/DO{sub 3b}-/A2{sub b}-type disorder in Mn{sub 2}CoSi. - Highlights: • The DO{sub 3}- and A2-type disorders do not affect the half-metallicity in Mn{sub 2}CoSi. • The B2-type disorder solely destroys half-metallicity in Mn{sub 2}CoSi. • The A2-type disorder most probable to occur out of all three types. • The total spin magnetic moment strongly depends on the disorder concentrations.

  9. SLUDGE BATCH 7 PREPARATION TANK 4 AND 12 CHARACTERIZATION

    SciTech Connect (OSTI)

    Bannochie, C.; Click, D.; Pareizs, J.

    2010-05-21

    Samples of PUREX sludge from Tank 4 and HM sludge from Tank 12 were characterized in preparation for Sludge Batch 7 (SB7) formulation in Tank 51. SRNL analyses on Tank 4 and Tank 12 were requested in separate Technical Assistance Requests (TAR). The Tank 4 samples were pulled on January 19, 2010 following slurry operations by F-Tank Farm. The Tank 12 samples were pulled on February 9, 2010 following slurry operations by H-Tank Farm. At the Savannah River National Laboratory (SRNL), two 200 mL dip samples of Tank 4 and two 200 mL dip samples of Tank 12 were received in the SRNL Shielded Cells. Each tank's samples were composited into clean 500 mL polyethylene storage bottles and weighed. The composited Tank 4 sample was 428.27 g and the composited Tank 12 sample was 502.15 g. As expected there are distinct compositional differences between Tank 4 and Tank 12 sludges. The Tank 12 slurry is much higher in Al, Hg, Mn, and Th, and much lower in Fe, Ni, S, and U than the Tank 4 slurry. The Tank 4 sludge definitely makes the more significant contribution of S to any sludge batch blend. This S, like that observed during SB6 washing, is best monitored by looking at the total S measured by digesting the sample and analyzing by inductively coupled plasma - atomic emission spectroscopy (ICPAES). Alternatively, one can measure the soluble S by ICP-AES and adjust the value upward by approximately 15% to have a pretty good estimate of the total S in the slurry. Soluble sulfate measurements by ion chromatography (IC) will be biased considerably lower than the actual total S, the difference being due to the non-sulfate soluble S and the undissolved S. Tank 12 sludge is enriched in U-235, and hence samples transferred into SRNL from the Tank Farm will need to be placed on the reportable special nuclear material inventory and tracked for total U per SRNL procedure requirements.

  10. Reduction of metastasis, cell invasion, and adhesion in mouse osteosarcoma by YM529/ONO-5920-induced blockade of the Ras/MEK/ERK and Ras/PI3K/Akt pathway

    SciTech Connect (OSTI)

    Tsubaki, Masanobu; Satou, Takao; Itoh, Tatsuki; Imano, Motohiro; Ogaki, Mitsuhiko; Yanae, Masashi; Depeartment of Pharmacy, Sakai Hospital, Kinki University School of Medicine, Sakai, Osaka 590-0132 ; Nishida, Shozo

    2012-03-15

    Osteosarcoma is one of the most common primary malignant bone tumors in children and adolescents. Some patients continue to have a poor prognosis, because of the metastatic disease. YM529/ONO-5920 is a nitrogen-containing bisphosphonate that has been used for the treatment of osteoporosis. YM529/ONO-5920 has recently been reported to induce apoptosis in various tumors including osteosarcoma. However, the mode of metastasis suppression in osteosarcoma by YM529/ONO-5920 is unclear. In the present study, we investigated whether YM529/ONO-5920 inhibited tumor cell migration, invasion, adhesion, or metastasis in the LM8 mouse osteosarcoma cell line. We found that YM529/ONO-5920 significantly inhibited metastasis, cell migration, invasion, and adhesion at concentrations that did not have antiproliferative effects on LM8 cells. YM529/ONO-5920 also inhibited the mRNA expression and protein activities of matrix metalloproteinases (MMPs). In addition, YM529/ONO-5920 suppressed phosphorylated extracellular signal-regulated kinase 1/2 (ERK1/2) and the serine/threonine protein kinase B (Akt) by the inhibition of Ras prenylation. Moreover, U0126, a mitogen-activated protein kinase kinase (MEK) 1/2 inhibitor, and LY294002, a phosphatidylinositol 3-kinase (PI3K) inhibitor, also inhibited LM8 cell migration, invasion, adhesion, and metastasis, as well as the mRNA expression and protein activities of MMP-1, MMP-2, MMP-9, and MT1-MMP. The results indicated that YM529/ONO-5920 suppressed the Ras/MEK/ERK and Ras/PI3K/Akt pathways, thereby inhibiting LM8 cell migration, invasion, adhesion, and metastasis. These findings suggest that YM529/ONO-5920 has potential clinical applications for the treatment of tumor cell metastasis in osteosarcoma. -- Highlights: ? We investigated whether YM529/ONO-5920 inhibited tumor metastasis in osteosarcoma. ? YM529/ONO-5920 inhibited metastasis, cell migration, invasion, and adhesion. ? YM529/ONO-5920 suppressed Ras signalings. ? YM529/ONO-5920 has potential clinical applications for the treatment in osteosarcoma.

  11. Search for [C II] emission in z = 6.5-11 star-forming galaxies

    SciTech Connect (OSTI)

    Gonzlez-Lpez, Jorge; Infante, Leopoldo; Riechers, Dominik A. E-mail: linfante@astro.puc.cl; and others

    2014-04-01

    We present the search for the [C II] emission line in three z > 6.5 Ly? emitters (LAEs) and one J-dropout galaxy using the Combined Array for Research in Millimeter-wave Astronomy and the Plateau de Bure Interferometer. We observed three bright z ? 6.5-7 LAEs discovered in the Subaru Deep Field (SDF) and the multiple imaged lensed z ? 11 galaxy candidate found behind the galaxy cluster MACSJ0647.7+7015. For the LAEs IOK-1 (z = 6.965), SDF J132415.7+273058 (z = 6.541), and SDF J132408.3+271543 (z = 6.554) we find upper limits for the [C II] line luminosity of <2.05, <4.52, and <10.56 10{sup 8} L {sub ?}, respectively. We find upper limits to the far-IR (FIR) luminosity of the galaxies using a spectral energy distribution template of the local galaxy NGC 6946 and taking into account the effects of the cosmic microwave background on the millimeter observations. For IOK-1, SDF J132415.7+273058, and SDF J132408.3+271543 we find upper limits for the FIR luminosity of <2.33, 3.79, and 7.72 10{sup 11} L {sub ?}, respectively. For the lensed galaxy MACS0647-JD, one of the highest-redshift galaxy candidates to date with z{sub ph}=10.7{sub ?0.4}{sup +0.6}, we put an upper limit in the [C II] emission of <1.36 10{sup 8} (?/15){sup 1} L {sub ?} and an upper limit in the FIR luminosity of <6.1 10{sup 10} (?/15){sup 1} L {sub ?} (where ? is the magnification factor). We explore the different conditions relevant for the search for [C II] emission in high-redshift galaxies as well as the difficulties for future observations with the Atacama Large Millimeter/submillimeter Array (ALMA) and the Cerro Chajnantor Atacama Telescope (CCAT).

  12. NEW PERSPECTIVE ON GALAXY OUTFLOWS FROM THE FIRST DETECTION OF BOTH INTRINSIC AND TRAVERSE METAL-LINE ABSORPTION

    SciTech Connect (OSTI)

    Kacprzak, Glenn G.; Cooke, Jeff; Martin, Crystal L.; Ho, Stephanie H.; Bouch, Nicolas; LeReun, Audrey; Schroetter, Ilane; Churchill, Christopher W.; Klimek, Elizabeth

    2014-09-01

    We present the first observation of a galaxy (z = 0.2) that exhibits metal-line absorption back-illuminated by the galaxy (down-the-barrel) and transversely by a background quasar at a projected distance of 58 kpc. Both absorption systems, traced by Mg II, are blueshifted relative to the galaxy systemic velocity. The quasar sight line, which resides almost directly along the projected minor axis of the galaxy, probes Mg I and Mg II absorption obtained from the Keck/Low Resolution Imaging Spectrometer as well as Ly?, Si II, and Si III absorption obtained from the Hubble Space Telescope/Cosmic Origins Spectrograph. For the first time, we combine two independent models used to quantify the outflow properties for down-the-barrel and transverse absorption. We find that the modeled down-the-barrel deprojected outflow velocities range between V {sub dtb} = 45-255 km s{sup 1}. The transverse bi-conical outflow model, assuming constant-velocity flows perpendicular to the disk, requires wind velocities V {sub outflow} = 40-80 km s{sup 1} to reproduce the transverse Mg II absorption kinematics, which is consistent with the range of V {sub dtb}. The galaxy has a metallicity, derived from H? and N II, of [O/H] = 0.21 0.08, whereas the transverse absorption has [X/H] = 1.12 0.02. The galaxy star formation rate is constrained between 4.6-15 M {sub ?} yr{sup 1} while the estimated outflow rate ranges between 1.6-4.2 M {sub ?} yr{sup 1} and yields a wind loading factor ranging between 0.1-0.9. The galaxy and gas metallicities, the galaxy-quasar sight-line geometry, and the down-the-barrel and transverse modeled outflow velocities collectively suggest that the transverse gas originates from ongoing outflowing material from the galaxy. The ?1 dex decrease in metallicity from the base of the outflow to the outer halo suggests metal dilution of the gas by the time it reached 58 kpc.

  13. ON THE KENNICUTT-SCHMIDT RELATION OF LOW-METALLICITY HIGH-REDSHIFT GALAXIES

    SciTech Connect (OSTI)

    Gnedin, Nickolay Y. [Particle Astrophysics Center, Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Kravtsov, Andrey V., E-mail: gnedin@fnal.go, E-mail: andrey@oddjob.uchicago.ed [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States)

    2010-05-01

    We present results of self-consistent, high-resolution cosmological simulations of galaxy formation at z {approx} 3. The simulations employ a recently developed recipe for star formation based on the local abundance of molecular hydrogen, which is tracked self-consistently during the course of simulation. The phenomenological H{sub 2} formation model accounts for the effects of dissociating UV radiation of stars in each galaxy, as well as self-shielding and shielding of H{sub 2} by dust, and therefore allows us to explore effects of lower metallicities and higher UV fluxes prevalent in high-redshift galaxies on their star formation. We compare stellar masses, metallicities, and star formation rates of the simulated galaxies to available observations of the Lyman break galaxies (LBGs) and find a reasonable agreement. We find that the Kennicutt-Schmidt (KS) relation exhibited by our simulated galaxies at z {approx} 3 is substantially steeper and has a lower amplitude than the z = 0 relation at {Sigma}{sub H} {approx_lt} 100 M{sub o-dot} pc{sup -2}. The predicted relation, however, is consistent with existing observational constraints for the z {approx} 3 damped Ly{alpha} and LBGs. Our tests show that the main reason for the difference from the local KS relation is lower metallicity of the interstellar medium in high-redshift galaxies. We discuss several implications of the metallicity-dependence of the KS relation for galaxy evolution and interpretation of observations. In particular, we show that the observed size of high-redshift exponential disks depends sensitively on their KS relation. Our results also suggest that significantly reduced star formation efficiency at low gas surface densities can lead to strong suppression of star formation in low-mass high-redshift galaxies and long gas consumption time scales over most of the disks in large galaxies. The longer gas consumption time scales could make disks more resilient to major and minor mergers and could help explain the prevalence of the thin stellar disks in the local universe.

  14. Functional Toll-like receptor 4 expressed in lactotrophs mediates LPS-induced proliferation in experimental pituitary hyperplasia

    SciTech Connect (OSTI)

    Sabatino, Mara Eugenia; Sosa, Liliana del Valle; Petiti, Juan Pablo; Mukdsi, Jorge Humberto; Mascanfroni, Ivn Daro; Pellizas, Claudia Gabriela; Gutirrez, Silvina; Torres, Alicia Ins; De Paul, Ana Luca

    2013-11-15

    Toll like receptor 4 (TLR4) has been characterized for its ability to recognize bacterial endotoxin lipopolysaccharide (LPS). Considering that infections or inflammatory processes might contribute to the progression of pituitary tumors, we analyzed the TLR4 functional role by evaluating the LPS effect on lactotroph proliferation in primary cultures from experimental pituitary tumors, and examined the involvement of PI3K-Akt and NF-?B activation in this effect. In addition, the role of 17?-estradiol as a possible modulator of LPS-induced PRL cell proliferation was further investigated. In estrogen-induced hyperplasic pituitaries, LPS triggered lactotroph cell proliferation. However, endotoxin failed to increase the number of lactotrophs taking up BrdU in normal pituitaries. Moreover, incubation with anti-TLR4 antibody significantly reduced LPS-induced lactotroph proliferation, suggesting a functional role of this receptor. As a sign of TLR4 activation, an LPS challenge increased IL-6 release in normal and tumoral cells. By flow cytometry, TLR4 baseline expression was revealed at the plasma membrane of tumoral lactotrophs, without changes noted in the percentage of double PRL/TLR4 positive cells after LPS stimulus. Increases in TLR4 intracellular expression were detected as well as rises in CD14, p-Akt and NF-?B after an LPS challenge, as assessed by western blotting. The TLR4/PRL and PRL/NF-?B co-localization was also corroborated by immunofluorescence and the involvement of PI3K/Akt signaling in lactotroph proliferation and IL-6 release was revealed through the PI3K inhibitor Ly-294002. In addition, 17?-estradiol attenuated the LPS-evoked increase in tumoral lactotroph proliferation and IL-6 release. Collectively these results demonstrate the presence of functional TLR4 in lactotrophs from estrogen-induced hyperplasic pituitaries, which responded to the proliferative stimulation and IL-6 release induced by LPS through TLR4/CD14, with a contribution of the PI3K-Akt and NF-?B signaling pathways. - Highlights: In hyperplastic pituitaries, LPS triggered the lactotroph cell proliferation and IL-6 release. Functional Toll-like receptor 4 (TLR4) is expressed at the plasma membrane of tumoral lactotrophs. Increases in TLR4 and CD14 intracellular expression levels were detected after an LPS challenge. The proliferative stimulation and IL-6 release involved the PI3K-Akt pathway and NF-?B activation. 17?-estradiol attenuated the LPS-evoked tumoral lactotroph proliferation and IL-6 secretion.

  15. CANDELS: THE CONTRIBUTION OF THE OBSERVED GALAXY POPULATION TO COSMIC REIONIZATION

    SciTech Connect (OSTI)

    Finkelstein, Steven L.; Pawlik, Andreas H.; Papovich, Casey; Ryan, Russell E.; Ferguson, Henry C.; Koekemoer, Anton M.; Grogin, Norman A.; Dickinson, Mark; Finlator, Kristian; Giavalisco, Mauro; Cooray, Asantha; Dunlop, James S.; Faber, Sandy M.; Kocevski, Dale D.

    2012-10-20

    We present measurements of the specific ultraviolet luminosity density from a sample of 483 galaxies at 6 {approx}< z {approx}< 8. These galaxies were selected from new deep near-infrared Hubble Space Telescope imaging from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey, Hubble UltraDeep Field 2009, and Wide Field Camera 3 Early Release Science programs. We investigate the contribution to reionization from galaxies that we observe directly, thus sidestepping the uncertainties inherent in complementary studies that have invoked assumptions regarding the intrinsic shape or the faint-end cutoff of the galaxy ultraviolet (UV) luminosity function. Due to our larger survey volume, wider wavelength coverage, and updated assumptions about the clumping of gas in the intergalactic medium (IGM), we find that the observable population of galaxies can sustain a fully reionized IGM at z = 6, if the average ionizing photon escape fraction (f {sub esc}) is {approx}30%. Our result contrasts with a number of previous studies that have measured UV luminosity densities at these redshifts that vary by a factor of five, with many concluding that galaxies could not complete reionization by z = 6 unless a large population of galaxies fainter than the detection limit were invoked, or extremely high values of f {sub esc} were present. The specific UV luminosity density from our observed galaxy samples at z = 7 and 8 is not sufficient to maintain a fully reionized IGM unless f {sub esc} > 50%. We examine the contribution from galaxies in different luminosity ranges and find that the sub-L* galaxies we detect are stronger contributors to the ionizing photon budget than the L > L* population, unless f {sub esc} is luminosity dependent. Combining our observations with constraints on the emission rate of ionizing photons from Ly{alpha} forest observations at z = 6, we find that we can constrain f {sub esc} < 34% (2{sigma}) if the observed galaxies are the only contributors to reionization, or <13% (2{sigma}) if the luminosity function extends to a limiting magnitude of M {sub UV} = -13. These escape fractions are sufficient to sustain an ionized IGM by z = 6. Current constraints on the high-redshift galaxy population imply that the volume ionized fraction of the IGM, while consistent with unity at z {<=} 6, appears to drop at redshifts not much higher than 7, consistent with a number of complementary reionization probes. If faint galaxies dominated the ionizing photon budget at z = 6-7, future extremely deep observations with the James Webb Space Telescope will probe deep enough to directly observe them, providing an indirect constraint on the global ionizing photon escape fraction.

  16. Strong chromatic microlensing in HE00471756 and SDSS1155+6346

    SciTech Connect (OSTI)

    Rojas, K.; Motta, V.; Mediavilla, E.; Jimnez-Vicente, J.; Muoz, J. A. E-mail: veronica.motta@uv.cl E-mail: falco@cfa.harvard.edu E-mail: jmunoz@uv.es

    2014-12-10

    We use spectra of the double-lensed quasars HE00471756 and SDSS1155+6346 to study their unresolved structure through the impact of microlensing. There is no significant evidence of microlensing in the emission line profiles except for the Ly? line of SDSS1155+6346, which shows strong differences in the shapes for images A and B. However, the continuum of the B image spectrum in SDSS1155+6346 is strongly contaminated by the lens galaxy, and these differences should be considered with caution. Using the flux ratios of the emission lines for image pairs as a baseline to remove macro-magnification and extinction, we have detected strong chromatic microlensing in the continuum measured by CASTLES (www.cfa.harvard.edu/castles/) in both lens systems, with amplitudes 0.09(?16000) ? |?m| ? 0.8(?5439) for HE00471756, and 0.2(?16000) ? |?m| ? 0.8(?5439) for SDSS1155+6346. Using magnification maps to simulate microlensing and modeling the accretion disk as a Gaussian source (I ? exp(R {sup 2}/2r {sub s}{sup 2})) of size r {sub s} ? ? {sup p}, we find r {sub s} = 2.5{sub ?1.4}{sup +3.0} ?(M/0.3M{sub ?}) lt-day and p = 2.3 0.8 at the rest frame for ? = 2045 for HE00471756 (log prior) and r {sub s} = 5.5{sub ?3.3}{sup +8.2} ?(M/0.3M{sub ?}) lt-day and p = 1.5 0.6 at the rest frame of ? = 1398 for SDSS1155+6346 (log prior). Contrary to other studied lens systems, the chromaticity detected in HE00471756 and SDSS1155+6346 is large enough to fulfill the thin disk prediction. The inferred sizes, however, are very large compared to the predictions of this model, especially in the case of SDSS1155+6346.

  17. UNDERSTANDING PHYSICAL CONDITIONS IN HIGH-REDSHIFT GALAXIES THROUGH C I FINE STRUCTURE LINES: DATA AND METHODOLOGY

    SciTech Connect (OSTI)

    Jorgenson, Regina A.; Wolfe, Arthur M.; Prochaska, J. Xavier

    2010-10-10

    We probe the physical conditions in high-redshift galaxies, specifically, the damped Ly{alpha} systems (DLAs) using neutral carbon (C I) fine structure lines and molecular hydrogen (H{sub 2}). We report five new detections of C I and analyze the C I in an additional two DLAs with previously published data. We also present one new detection of H{sub 2} in a DLA. We present a new method of analysis that simultaneously constrains both the volume density and the temperature of the gas, as opposed to previous studies that a priori assumed a gas temperature. We use only the column density of C I measured in the fine structure states and the assumption of ionization equilibrium in order to constrain the physical conditions in the gas. We present a sample of 11 C I velocity components in six DLAs and compare their properties to those derived by the global C II* technique. The resulting median values for this sample are (n(H I)) = 69 cm{sup -3}, (T) = 50 K, and (log(P/k)) = 3.86 cm{sup -3} K, with standard deviations, {sigma}{sub n(H{sub i})} = 134 cm{sup -3}, {sigma}{sub T} = 52 K, and {sigma}{sub log(P/k)} = 3.68 cm{sup -3} K. This can be compared with the integrated median values for the same DLAs: (n(H I)) = 2.8 cm{sup -3}, (T) = 139 K, and (log(P/k)) = 2.57 cm{sup -3} K, with standard deviations {sigma}{sub n(H{sub i})} = 3.0 cm{sup -3}, {sigma}{sub T} = 43 K, and {sigma}{sub log(P/k)} = 0.22 cm{sup -3} K. Interestingly, the pressures measured in these high-redshift C I clouds are similar to those found in the Milky Way. We conclude that the C I gas is tracing a higher-density, higher-pressure region, possibly indicative of post-shock gas or a photodissociation region on the edge of a molecular cloud. We speculate that these clouds may be direct probes of the precursor sites of star formation in normal galaxies at high redshift.

  18. HD/H{sub 2} AS A PROBE OF THE ROLES OF GAS, DUST, LIGHT, METALLICITY, AND COSMIC RAYS IN PROMOTING THE GROWTH OF MOLECULAR HYDROGEN IN THE DIFFUSE INTERSTELLAR MEDIUM

    SciTech Connect (OSTI)

    Liszt, H. S.

    2015-01-20

    We modeled recent observations of UV absorption of HD and H{sub 2} in the Milky Way and toward damped/subdamped Lyα systems at z = 0.18 and z >1.7. N(HD)/N(H{sub 2}) ratios reflect the separate self-shieldings of HD and H{sub 2} and the coupling introduced by deuteration chemistry. Locally, observations are explained by diffuse molecular gas with 16 cm{sup –3} ≲ n(H) ≲ 128 cm{sup –3} if the cosmic-ray ionization rate per H nucleus ζ {sub H} =2 × 10{sup –16} s{sup –1}, as inferred from H{sub 3} {sup +} and OH{sup +}. The dominant influence on N(HD)/N(H{sub 2}) is the cosmic-ray ionization rate with a much weaker downward dependence on n(H) at solar metallicity, but dust extinction can drive N(HD) higher as with N(H{sub 2}). At z > 1.7, N(HD) is comparable to the Galaxy but with 10 times smaller N(H{sub 2}) and somewhat smaller N(H{sub 2})/N(H I). Comparison of our Galaxy with the Magellanic Clouds shows that smaller H{sub 2}/H is expected at subsolar metallicity, and we show by modeling that HD/H{sub 2} increases with density at low metallicity, opposite to the Milky Way. Observations of HD would be explained with higher n(H) at low metallicity, but high-z systems have high HD/H{sub 2} at metallicity 0.04 ≲ Z ≲ 2 solar. In parallel, we trace dust extinction and self-shielding effects. The abrupt H{sub 2} transition to H{sub 2}/H ≈ 1%-10% occurs mostly from self-shielding, although it is assisted by extinction for n(H) ≲ 16 cm{sup –3}. Interior H{sub 2} fractions are substantially increased by dust extinction below ≲ 32 cm{sup –3}. At smaller n(H), ζ {sub H}, small increases in H{sub 2} triggered by dust extinction can trigger abrupt increases in N(HD)

  19. HST/COS OBSERVATIONS OF THE QUASAR HE 2347-4342: PROBING THE EPOCH OF He II PATCHY REIONIZATION AT REDSHIFTS z = 2.4-2.9

    SciTech Connect (OSTI)

    Shull, J. Michael; France, Kevin; Danforth, Charles W.; Smith, Britton [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, 389-UCB, Boulder, CO 80309 (United States); Tumlinson, Jason, E-mail: michael.shull@colorado.ed, E-mail: danforth@casa.colorado.ed, E-mail: kevin.france@colorado.ed, E-mail: britton.smith@colorado.ed, E-mail: tumlinson@stsci.ed [Space Telescope Science Institute, Baltimore, MD 21218 (United States)

    2010-10-20

    We report ultraviolet spectra of the high-redshift (z{sub em} {approx} 2.9) quasar, HE 2347 - 4342, taken by the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope. Spectra in the G130M (medium resolution, 1135-1440 A) and G140L (low resolution, 1030-2000 A) gratings exhibit patchy Gunn-Peterson absorption in the 303.78 A Ly{alpha} line of He II between z = 2.39-2.87 (G140L) and z = 2.74-2.90 (G130M). With COS, we obtain better spectral resolution, higher signal-to-noise ratio (S/N), and better determined backgrounds than previous studies, with sensitivity to abundance fractions x{sub He{sub II}} {approx} 0.01 in filaments of the cosmic web. The He II optical depths from COS are higher than those with the Far Ultraviolet Spectroscopic Explorer and range from {tau}{sub He{sub II}} {<=} 0.02 to {tau}{sub He{sub II}} {>=} 5, with a slow recovery in mean optical depth to ({tau}{sub He{sub II}}) {<=} 2 at z < 2.7. The He II/H I optical-depth ratio varies ({eta}{approx} 10-100 for 2.4 < z < 2.73 and {eta} = 5-500 for 2.75 < z < 2.89) on scales {Delta}z {approx}< 0.01 (10.8 Mpc in comoving radial distance at z = 2.8), with numerous flux-transmission windows between 1135 and 1186 A. The He II absorption extends to 1186.26 A (z = 2.905), including associated absorbers with z{sub abs} {approx} z{sub QSO} and minimal 'proximity effect' of flux transmission at the He II edge. We propose a QSO systemic redshift z{sub QSO} = 2.904 {+-} 0.002, some {Delta}z = 0.019 higher than that derived from O I {lambda}1302 emission. Three long troughs (4-10 A or 25-60 Mpc comoving distance) of strong He II absorption between z = 2.75and2.90 are uncharacteristic of the intergalactic medium if He II reionized at z{sub r} {approx} 3. Contrary to recent indirect estimates (z{sub r} = 3.2 {+-} 0.2) from H I optical depths, the epoch of He II reionization may extend to z {approx}< 2.7.

  20. CO AND H{sub 2} ABSORPTION IN THE AA TAURI CIRCUMSTELLAR DISK

    SciTech Connect (OSTI)

    France, Kevin; Burgh, Eric B.; Schindhelm, Eric; Brown, Alexander; Herczeg, Gregory J.; Yang, Hao; Linsky, Jeffrey L.; Abgrall, Herve; Roueff, Evelyne; Brown, Joanna M.

    2012-01-01

    The direct study of molecular gas in inner protoplanetary disks is complicated by uncertainties in the spatial distribution of the gas, the time variability of the source, and the comparison of observations across a wide range of wavelengths. Some of these challenges can be mitigated with far-ultraviolet spectroscopy. Using new observations obtained with the Hubble Space Telescope Cosmic Origins Spectrograph, we measure column densities and rovibrational temperatures for CO and H{sub 2} observed on the line of sight through the AA Tauri circumstellar disk. CO A - X absorption bands are observed against the far-UV continuum. The CO absorption is characterized by log{sub 10}(N({sup 12}CO)) = 17.5 {+-} 0.5 cm{sup -2} and T{sub rot}(CO) = 500{sup +500}{sub -200} K, although this rotational temperature may underestimate the local kinetic temperature of the CO-bearing gas. We also detect {sup 13}CO in absorption with an isotopic ratio of {approx}20. We do not observe H{sub 2} absorption against the continuum; however, hot H{sub 2} (v > 0) is detected in absorption against the Ly{alpha} emission line. We measure the column densities in eight individual rovibrational states, determining a total log{sub 10}(N(H{sub 2})) = 17.9{sup +0.6}{sub -0.3} cm{sup -2} with a thermal temperature of T(H{sub 2}) = 2500{sup +800}{sub -700} K. The high temperature of the molecules, the relatively small H{sub 2} column density, and the high inclination of the AA Tauri disk suggest that the absorbing gas resides in an inner disk atmosphere. If the H{sub 2} and CO are cospatial within a molecular layer {approx}0.6 AU thick, this region is characterized by {approx} 10{sup 5} cm{sup -3} with an observed (CO/H{sub 2}) ratio of {approx}0.4. We also find evidence for a departure from a purely thermal H{sub 2} distribution, suggesting that excitation by continuum photons and H{sub 2} formation may be altering the level populations in the molecular gas.

  1. DOE/EPRI Electricity Storage Handbook in Collaboration with NRECA.

    SciTech Connect (OSTI)

    Huff, Georgianne; Huff, Georgianne; Akhil, Abbas Ali; Akhil, Abbas Ali; Kaun, Benjamin C; Kaun, Benjamin C; Rastler, Dan M.; Rastler, Dan M.; Chen, Stella Bingqing; Chen, Stella Bingqing; Cotter, Andrew L.; Cotter, Andrew L.; Bradshaw, Dale T.; Bradshaw, Dale T.; Gauntlett, William D.; Gauntlett, William D.; Currier, Aileen B.; Currier, Aileen B.

    2015-02-01

    Th e Electricity Storage Handbook (Handbook) is a how - to guide for utility and rural cooperative engineers, planners , and decision makers to plan and implement energy storage projects . The H andbook also serves as an information resource for investors and venture capitalists , providing the latest develo pments in technologies and tools to guide their evaluation s of energy storage opportunities . It includes a comprehensive database of the cost of current storage systems in a wide variety of electric utility and customer services, along with interconnection schematics . A list of significant past and present energy storage projects is provided for a practical perspective . Th is Handbook, jointly sponsored by the U.S. Department of Energy and the Electric Power Research Institute in collaboration with the National Rural Electric Cooperative Associ ation , is published in electronic form at www.sandia.gov/ess . This Handbook is best viewed online. iii Rev. 1, September 2014 DOE/EPRI Electricity Storage Handbook in Collaboration with NRECA Revision Log Comments, inquiries, corrections, and suggestions can be submitted via the website www.sandia.gov/ess/ , beginning August 1 , 2013. REVISION LOG Rev . Number Date Purpose of Revision Document Number Name or Org. Rev. 0 July 2013 Update and revise the 2003 EPRI - DOE Handbook of Energy Storage for Transmission and Distribution Applications to provide how - to information for various stakeholders. SAND2013 - 5131 DOE (SNL), EPRI, NRECA Rev. 1 Sept. 2014 Chapter 2: * Added information highlighting thermal storage solution. Chapter 3: * Added subchapter highlighting tools available to use to evaluate a Storage solution from a model ing and simulation standpoint. * Added new Subsections 3.3.1 through 3.3.6 . Chapter 4: * With respect to the "AC battery" system: o Added a reference to the patent #4,894,764. o Added a picture of an AC battery . * Added information about KIUC and the RFI and RFP. Appendix A: * Added information regarding ES models and tools. Appendix B: * Expanded on three energy and power cost components. o Calculation of the sum of the energy and power components. o How these costs are highly system dependent and do not scale linear ly. * Expanded on d eri vation of the Total Plant Cost (TPC) and referenced costs that are components of the TPC. * Added explanation of equipment costs . Appendix F: * Added introductory text. Appendix G: * Added reference to AC battery patent . * Removed Hawaii battery projects information. SAND201 5 - XXXX iv Rev. 1, September 201

  2. Impact of Nuclear Energy Futures on Advanced Fuel Cycle Options

    SciTech Connect (OSTI)

    Brent W. Dixon; Steven J. Piet

    2004-10-01

    The Nuclear Waste Policy Act requires the Secretary of Energy to inform Congress before 2010 on the need for a second geologic repository for spent nuclear fuel. By that time, the spent fuel discharged from current commercial reactors will exceed the statutory limit of the first repository (63,000 MTiHM commercial, 7,000 MT non-commercial). There are several approaches to eliminate the need for another repository in this century. This paper presents a high-level analysis of these spent fuel management options in the context of a full range of possible nuclear energy futures. The analysis indicates the best option to implement varies depending on the nuclear energy future selected. The first step in understanding the need for different spent fuel management approaches is to understand the size of potential spent fuel inventories. A full range of potential futures for domestic commercial nuclear energy is considered. These energy futures are as follows: 1. Existing License Completion - Based on existing spent fuel inventories plus extrapolation of future plant-by-plant discharges until the end of each operating license, including known license extensions. 2. Extended License Completion - Based on existing spent fuel inventories plus a plant-by-plant extrapolation of future discharges assuming on all operating plants having one 20-year extension. 3. Continuing Level Energy Generation - Based on extension of the current ~100 GWe installed commercial base and average spent fuel discharge of 2100 MT/yr through the year 2100. 4. Continuing Market Share Generation Based on a 1.8% compounded growth of the electricity market through the year 2100, matched by growing nuclear capacity and associated spent fuel discharge. 5. Growing Market Share Generation - Extension of current nuclear capacity and associated spent fuel discharge through 2100 with 3.2% growth representing 1.5% market growth (all energy, not just electricity) and 1.7% share growth. Share growth results in tripling market share by 2100 from the current 8.4% to 25%, equivalent to continuing the average market growth of last 50 years for an additional 100 years. Five primary spent fuel management strategies are assessed against each of the energy futures to determine the number of geological repositories needed and how the first repository would be used. The geological repository site at Yucca Mountain, Nevada, has the physical potential to accommodate all the spent fuel that will be generated by the current fleet of domestic commercial nuclear reactors, even with license extensions. If new nuclear plants are built in the future as replacements or additions, the United States will need to adopt spent fuel treatment to extend the life of the repository. Should a significant number of new nuclear plants be built, advanced fuel recycling will be needed to fully manage the spent fuel within a single repository. The analysis also considers the timeframe for most efficient implementation of new spent fuel management strategies. The mix of unprocessed spent fuel and processed high level waste in Yucca Mountain varies with each future and strategy. Either recycling must start before there is too much unprocessed waste emplaced or unprocessed waste will have to be retrieved later with corresponding costs. For each case, the latest date to implement reprocessing without subsequent retrieval is determined.

  3. Preliminary core design studies for the advanced burner reactor over a wide range of conversion ratios.

    SciTech Connect (OSTI)

    Hoffman, E. A.; Yang, W. S.; Hill, R. N.; Nuclear Engineering Division

    2008-05-05

    A consistent set of designs for 1000 MWt commercial-scale sodium-cooled Advance Burner Reactors (ABR) have been developed for both metal and oxide-fueled cores with conversion ratios from breakeven (CR=1.0) to fertile-free (CR=0.0). These designs are expected to satisfy thermal and irradiation damage limits based on the currently available data. The very low conversion ratio designs require fuel that is beyond the current fuel database, which is anticipated to be qualified by and for the Advanced Burned Test Reactor. Safety and kinetic parameters were calculated, but a safety analysis was not performed. Development of these designs was required to achieve the primary goal of this study, which was to generate representative fuel cycle mass flows for system studies of ABRs as part of the Global Nuclear Energy Partnership (GNEP). There are slight variations with conversion ratio but the basic ABR configuration consists of 144 fuel assemblies and between 9 and 22 primary control assemblies for both the metal and oxide-fueled cores. Preliminary design studies indicated that it is feasible to design the ABR to accommodate a wide range of conversion ratio by employing different assembly designs and including sufficient control assemblies to accommodate the large reactivity swing at low conversion ratios. The assemblies are designed to fit within the same geometry, but the size and number of fuel pins within each assembly are significantly different in order to achieve the target conversion ratio while still satisfying thermal limits. Current irradiation experience would allow for a conversion ratio of somewhat below 0.75. The fuel qualification for the first ABR should expand this experience to allow for much lower conversion ratios and higher bunrups. The current designs were based on assumptions about the performance of high and very high enrichment fuel, which results in significant uncertainty about the details of the designs. However, the basic fuel cycle performance trends such as conversion ratio and mass flow parameters are less sensitive to these parameters and the current results should provide a good basis for static and dynamic system analysis. The conversion ratio is fundamentally a ratio of the macroscopic cross section of U-238 capture to that of TRU fission. Since the microscopic cross sections only change moderately with fuel design and isotopic concentration for the fast reactor, a specific conversion ratio requires a specific enrichment. The approximate average charge enrichment (TRU/HM) is 14%, 21%, 33%, 56%, and 100% for conversion ratios of 1.0, 0.75, 0.50, 0.25, and 0.0 for the metal-fueled cores. The approximate average charge enrichment is 17%, 25%, 38%, 60%, and 100% for conversion ratios of 1.0, 0.75, 0.50, 0.25, and 0.0 for the oxide-fueled core. For the split batch cores, the maximum enrichment will be somewhat higher. For both the metal and oxide-fueled cores, the reactivity feedback coefficients and kinetics parameters seem reasonable. The maximum single control assembly reactivity faults may be too large for the low conversion ratio designs. The average reactivity of the primary control assemblies was increased, which may cause the maximum reactivity of the central control assembly to be excessive. The values of the reactivity coefficients and kinetics parameters show that some values appear to improve significantly at lower conversion ratios while others appear far less favorable. Detailed safety analysis is required to determine if these designs have adequate safety margins or if appropriate design modifications are required. Detailed system analysis data has been generated for both metal and oxide-fueled core designs over the entire range of potential burner reactors. Additional data has been calculated for a few alternative fuel cycles. The systems data has been summarized in this report and the detailed data will be provided to the systems analysis team so that static and dynamic system analyses can be performed.

  4. TANK 4 CHARACTERIZATION, SETTLING, AND WASHING STUDIES

    SciTech Connect (OSTI)

    Bannochie, C.; Pareizs, J.; Click, D.; Zamecnik, J.

    2009-09-29

    A sample of PUREX sludge from Tank 4 was characterized, and subsequently combined with a Tank 51 sample (Tank 51-E1) received following Al dissolution, but prior to a supernate decant by the Tank Farm, to perform a settling and washing study to support Sludge Batch 6 preparation. The sludge source for the majority of the Tank 51-E1 sample is Tank 12 HM sludge. The Tank 51-E1 sample was decanted by SRNL prior to use in the settling and washing study. The Tank 4 sample was analyzed for chemical composition including noble metals. The characterization of the Tank 51-E1 sample, used here in combination with the Tank 4 sample, was reported previously. SRNL analyses on Tank 4 were requested by Liquid Waste Engineering (LWE) via Technical Task Request (TTR) HLE-TTR-2009-103. The sample preparation work is governed by Task Technical and Quality Assurance Plan (TTQAP), and analyses were controlled by an Analytical Study Plan and modifications received via customer communications. Additional scope included a request for a settling study of decanted Tank 51-E1 and a blend of decanted Tank 51-E1 and Tank 4, as well as a washing study to look into the fate of undissolved sulfur observed during the Tank 4 characterization. The chemistry of the Tank 4 sample was modeled with OLI Systems, Inc. StreamAnalyzer to determine the likelihood that sulfate could exist in this sample as insoluble Burkeite (2Na{sub 2}SO{sub 4} {center_dot} Na{sub 2}CO{sub 3}). The OLI model was also used to predict the composition of the blended tank materials for the washing study. The following conclusions were drawn from the Tank 4 analytical results reported here: (1) Any projected blend of Tank 4 and the current Tank 51 contents will produce a SB6 composition that is lower in Ca and U than the current SB5 composition being processed by DWPF. (2) Unwashed Tank 4 has a relatively large initial S concentration of 3.68 wt% on a total solids basis, and approximately 10% of the total S is present as an insoluble or undissolved form. (3) There is 19% more S than can be accounted for by IC sulfate measurement. This additional soluble S is detected by ICP-AES analysis of the supernate. (4) Total supernate and slurry sulfur by ICP-AES should be monitored during washing in addition to supernate sulfate in order to avoid under estimating the amount of sulfur species removed or remaining in the supernate. (5) OLI simulation calculations show that the presence of undissolved Burkeite in the Tank 4 sample is reasonable, assuming a small difference in the Na concentration that is well within the analytical uncertainties of the reported value. The following conclusions were drawn from the blend studies of Tank 4 and decanted Tank 51-E1: (1) The addition of Tank 4 slurry to a decanted Tank 51-E1 sample significantly improved the degree and time for settling. (2) The addition of Tank 4 slurry to a decanted Tank 51-E1 sample significantly improved the plastic viscosity and yield stress. (3) The SRNL washing test, where nearly all of the wash solution was decanted from the solids, indicates that approximately 96% or more of the total S was removed from the blend in these tests, and the removal of the sulfur tracks closely with that of Na. Insoluble (undissolved) S remaining in the washed sludge was calculated from an estimate of the final slurry liquid fraction, the S result in the slurry digestion, and the S in the final decant (which was very close to the method detection limit). Based on this calculated result, about 4% of the initial total S remained after these washes; this amount is equivalent to about 18% of the initially undissolved S.