Zobrazeno 1 - 10
of 101
pro vyhledávání: '"Davis, David S."'
Autor:
Teng, Stacy H., Mushotzky, Richard F., Sambruna, Rita M., Davis, David S., Reynolds, Christopher S.
We present the analysis of 2.1 years of Fermi/LAT data on 491 Seyfert galaxies detected by the Swift/BAT survey. Only the two nearest objects, NGC 1068 and NGC 4945, which were identified in the Fermi First-year Catalog, are detected. Using the Swift
Externí odkaz:
http://arxiv.org/abs/1109.2734
We present the mass-X-ray observable scaling relationships for clusters of galaxies using the XMM-Newton cluster catalog of Snowden et al. Our results are roughly consistent with previous observational and theoretical work, with one major exception.
Externí odkaz:
http://arxiv.org/abs/0912.4078
Autor:
Georganopoulos, Markos, Sambruna, Rita M., Kazanas, Demosthenes, Cillis, Analia N., Cheung, Chi C., Perlman, Eric S., Blundell, Katherine M., Davis, David S.
We describe a new method for measuring the extragalactic background light (EBL) through the detection of $\gamma$-ray inverse Compton (IC) emission due to scattering of the EBL photons off relativistic electrons in the lobes of radio galaxies. Our me
Externí odkaz:
http://arxiv.org/abs/0808.4086
Publikováno v:
Astrophys.J.646:143-160,2006
We present the results of the 2-dimensional XMM-Newton Group Survey (2dXGS), an archival study of nearby galaxy groups. In this paper we consider eleven nearby systems (z<0.012) in Mulchaey et al. (2003), which span a broad range in X-ray luminosity
Externí odkaz:
http://arxiv.org/abs/astro-ph/0611858
Autor:
Burgett, William S., Vick, Michael M., Davis, David S., Colless, Matthew, De Propris, Roberto, Baldry, Ivan, Baugh, Carlton, Bland-Hawthorn, Joss, Bridges, Terry, Cannon, Russell, Cole, Shaun, Collins, Chris, Couch, Warrick, Cross, Nicholas, Dalton, Gavin, Driver, Simon, Efstathiou, George, Ellis, Richard, Frenk, Carlos, Glazebrook, Karl, Hawkins, Edward, Jackson, Carole, Lahav, Ofer, Lewis, Ian, Lumsden, Stuart, Maddox, Steve, Madgwick, Darren, Norberg, Peder, Peacock, John A., Percival, Will, Peterson, Bruce, Sutherland, Will, Taylor, Keith
Publikováno v:
Mon.Not.Roy.Astron.Soc.352:605,2004
Complementary one-, two-, and three-dimensional tests for detecting the presence of substructure in clusters of galaxies are applied to recently obtained data from the 2dF Galaxy Redshift Survey. The sample of 25 clusters used in this study includes
Externí odkaz:
http://arxiv.org/abs/astro-ph/0405021
Autor:
Davis, David S., Mushotzky, Richard F.
Publikováno v:
Astrophys.J. 604 (2004) 653-661
We present the results from a ~53 ksec XMM observation of NGC 2276. This galaxy has an unusual optical morphology with the disk of this spiral appearing to be truncated along the western edge. This XMM observation shows that the X-ray source at the w
Externí odkaz:
http://arxiv.org/abs/astro-ph/0312211
A search was conducted for a hot intragroup medium in 109 low-redshift galaxy groups observed with the ROSAT PSPC. Evidence for diffuse, extended X-ray emission is found in at least 61 groups. Approximately one-third of these detections have not been
Externí odkaz:
http://arxiv.org/abs/astro-ph/0302393
We have analyzed the ASCA data of 29 nearby clusters of galaxies systematically, and obtained temperatures, iron abundances, and X-ray luminosities of their intracluster medium (ICM). We also estimate ICM mass using the beta model, and then evaluate
Externí odkaz:
http://arxiv.org/abs/astro-ph/9911388
A temperature map of the A3266 galaxy cluster has been derived from the ASCA GIS observations. It shows an asymmetric pattern of heating indicative of an ongoing merger between a group sized sub-cluster and the main cluster. The galaxy distribution s
Externí odkaz:
http://arxiv.org/abs/astro-ph/9909243
We have analyzed the ASCA SIS and GIS data for seventeen groups and determined the average temperature and abundance of the hot x-ray emitting gas. For groups with gas temperatures less than 1.5 keV we find that the abundance is correlated with the g
Externí odkaz:
http://arxiv.org/abs/astro-ph/9808085