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43
Sep 23, 2013
09/13
by
A. Alonso-Herrero; P. G. Perez-Gonzalez; D. M. Alexander; G. H. Rieke; D. Rigopoulou; E. Le Floc'h; P. Barmby; C. Papovich; J. R. Rigby; F. E. Bauer; W. N. Brandt; E. Egami; S. P. Willner; H. Dole; J. -S. Huang
texts
eye 43
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We investigate the nature of a sample of 92 Spitzer/MIPS 24 micron selected galaxies in the CDFS, showing power law-like emission in the Spitzer/IRAC 3.6-8 micron bands. The main goal is to determine whether the galaxies not detected in X-rays (47% of the sample) are part of the hypothetical population of obscured AGN not detected even in deep X-ray surveys. The majority of the IR power-law galaxies are ULIRGs at z>1, and those with LIRG-like IR luminosities are usually detected in X-rays....
Source: http://arxiv.org/abs/astro-ph/0511507v1
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12
Jun 27, 2018
06/18
by
A. Del Moro; D. M. Alexander; F. E. Bauer; E. Daddi; D. D. Kocevski; D. H. McIntosh; F. Stanley; W. N. Brandt; D. Elbaz; C. M. Harrison; B. Luo; J. R. Mullaney; Y. Q. Xue
texts
eye 12
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We present the infrared (IR) and X-ray properties of a sample of 33 mid-IR luminous quasars ($\nu$L(6 micron)>6x10$^{44}$ erg/s) at redshift z~1-3, identified through detailed spectral energy distribution analyses of distant star-forming galaxies, using the deepest IR data from Spitzer and Herschel in the GOODS-Herschel fields. The aim is to constrain the fraction of obscured, and Compton-thick (CT, N$_H$>1.5x10$^{24}$ cm$^{-2}$) quasars at the peak era of nuclear and star-formation...
Topics: Astrophysics of Galaxies, Astrophysics
Source: http://arxiv.org/abs/1504.03329
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49
Sep 22, 2013
09/13
by
A. Del Moro; D. M. Alexander; J. R. Mullaney; E. Daddi; M. Pannella; F. E. Bauer; A. Pope; M. Dickinson; D. Elbaz; P. D. Barthel; M. A. Garrett; W. N. Brandt; V. Charmandaris; R. R. Chary; K. Dasyra; R. Gilli; R. C. Hickox; H. S. Hwang; R. J. Ivison; S. Juneau; E. Le Floc'h; B. Luo; G. E. Morrison; E. Rovilos; M. T. Sargent; Y. Q. Xue
texts
eye 49
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We present here a new spectral energy distribution (SED) fitting approach that we adopt to select radio-excess sources amongst distant star-forming galaxies in the GOODS-Herschel (North) field and to reveal the presence of hidden, highly obscured AGN. Through extensive SED analysis of 458 galaxies with radio 1.4 GHz and mid-IR 24 um detections using some of the deepest Chandra X-ray, Spitzer and Herschel infrared, and VLA radio data available to date, we have robustly identified a sample of 51...
Source: http://arxiv.org/abs/1210.2521v1
42
42
Sep 22, 2013
09/13
by
A. E. Hornschemeier; D. M. Alexander; F. E. Bauer; W. N. Brandt; R. Chary; C. Conselice; N. A. Grogin; A. M. Koekemoer; B. Mobasher; M. Paolillo; S. Ravindranath; E. J. Schreier
texts
eye 42
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We have identified a sample of 10 highly reliable off-nuclear (> 2 kpc) X-ray sources at z=0.03-0.25 in late-type host galaxies within the two GOODS fields (i.e., the two Chandra Deep Fields). The combination of the superb spatial resolution and great depth of the HST ACS and Chandra ACIS coverage in the GOODS fields is critical to the identification of these sources. We extend the study of this enigmatic population up to higher redshifts and larger look-back times than has been possible...
Source: http://arxiv.org/abs/astro-ph/0308408v1
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42
Sep 18, 2013
09/13
by
A. J. Barger; L. L. Cowie; P. Capak; D. M. Alexander; F. E. Bauer; E. Fernandez; W. N. Brandt; G. P. Garmire; A. E. Hornschemeier
texts
eye 42
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We present an optical and NIR catalog for the X-ray sources in the 2 Ms Chandra observation of the Hubble Deep Field-North region. We have high-quality multicolor images of all 503 X-ray point sources and reliable spectroscopic redshifts for 284. We spectroscopically identify six z>1 type II quasars. Our spectroscopic completeness for the R
Source: http://arxiv.org/abs/astro-ph/0306212v1
79
79
Sep 18, 2013
09/13
by
Anton M. Koekemoer; D. M. Alexander; F. E. Bauer; J. Bergeron; W. N. Brandt; E. Chatzichristou; S. Cristiani; S. M. Fall; N. A. Grogin; M. Livio; V. Mainieri; L. Moustakas; P. Padovani; P. Rosati; E. J. Schreier; C. M. Urry
texts
eye 79
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We describe a possible new class of X-ray sources that have robust detections in ultra-deep Chandra data, yet have no detections at all in our deep multi-band GOODS Hubble Space Telescope (HST) ACS images, which represent the highest quality optical imaging obtained to date on these fields. These extreme X-ray / Optical ratio sources ("EXO"s) have values of Fx/Fopt at least an order of magnitude above those generally found for other AGN, even those that are harbored by reddened hosts....
Source: http://arxiv.org/abs/astro-ph/0306407v1
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49
Sep 18, 2013
09/13
by
B. D. Lehmer; W. N. Brandt; D. M. Alexander; E. F. Bell; A. E. Hornschemeier; D. H. McIntosh; F. E. Bauer; R. Gilli; V. Mainieri; D. P. Schneider; J. D. Silverman; A. T. Steffen; P. Tozzi; C. Wolf
texts
eye 49
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We report on the X-ray evolution over the last ~9 Gyr of cosmic history (i.e., since z = 1.4) of late-type galaxy populations in the Chandra Deep Field-North and Extended Chandra Deep Field-South (CDF-N and E-CDF-S, respectively; jointly CDFs) survey fields. Our late-type galaxy sample consists of 2568 galaxies, which were identified using rest-frame optical colors and HST morphologies. We utilized X-ray stacking analyses to investigate the X-ray emission from these galaxies, emphasizing the...
Source: http://arxiv.org/abs/0803.3620v2
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50
Sep 20, 2013
09/13
by
B. D. Lehmer; W. N. Brandt; D. M. Alexander; E. F. Bell; D. H. McIntosh; F. E. Bauer; G. Hasinger; V. Mainieri; T. Miyaji; D. P. Schneider; A. T. Steffen
texts
eye 50
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We investigate the evolution over the last 6.3 Gyr of cosmic time (i.e., since z ~ 0.7) of the average X-ray properties of early-type galaxies within the Extended Chandra Deep Field-South (E-CDF-S). Our early-type galaxy sample includes 539 objects with red-sequence colors and Sersic indices larger than n = 2.5, which were selected jointly from the COMBO-17 (Classifying Objects by Medium-Band Observations in 17 Filters) and GEMS (Galaxy Evolution from Morphologies and SEDs) surveys. We utilize...
Source: http://arxiv.org/abs/astro-ph/0612003v1
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112
Jul 20, 2013
07/13
by
D. J. Rosario; P. Santini; D. Lutz; L. Shao; R. Maiolino; D. M. Alexander; B. Altieri; P. Andreani; H. Aussel; F. E. Bauer; S. Berta; A. Bongiovanni; W. N. Brandt; M. Brusa; J. Cepa; A. Cimatti; T. J. Cox; E. Daddi; D. Elbaz; A. Fontana; N. M. Förster Schreiber; R. Genzel; A. Grazian; E. Le Floch; B. Magnelli; V. Mainieri; H. Netzer; R. Nordon; I. Pérez Garcia; A. Poglitsch; P. Popesso; F. Pozzi; L. Riguccini; G. Rodighiero; M. Salvato; M. Sanchez-Portal; E. Sturm; L. J. Tacconi; I....
texts
eye 112
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(Abridged) We study relationships between the SFR and the nuclear properties of X-ray selected AGNs out to z=2.5, using far-IR data in three extragalactic deep fields as part of the PACS Evolutionary Probe (PEP) program. Guided by studies of intrinsic infra-red AGN SEDs, we show that the majority of the FIR emission in AGNs is produced by cold dust heated by star-formation. We uncover characteristic redshift-dependent trends between the mean FIR luminosity (L_fir) and accretion luminosity...
Source: http://arxiv.org/abs/1203.6069v2
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52
Sep 21, 2013
09/13
by
D. M. Alexander; F. E. Bauer; W. N. Brandt; E. Daddi; R. C. Hickox; B. D. Lehmer; B. Luo; Y. Q. Xue; M. Young; A. Comastri; A. Del Moro; A. C. Fabian; R. Gilli; A. D. Goulding; V. Mainieri; J. R. Mullaney; M. Paolillo; D. A. Rafferty; D. P. Schneider; O. Shemmer; C. Vignali
texts
eye 52
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We use the 4Ms CDF-S survey to place direct X-ray constraints on the ubiquity of z~2 heavily obscured AGNs in K 1E43 erg/s) heavily obscured and Compton-thick AGNs at z~2. Our space-density constraints are conservative lower limits but they are already consistent with the range of predictions from X-ray background models.
Source: http://arxiv.org/abs/1106.1443v1
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49
Sep 18, 2013
09/13
by
D. M. Alexander; R. R. Chary; A. Pope; F. E. Bauer; W. N. Brandt; E. Daddi; M. Dickinson; D. Elbaz; N. A. Reddy
texts
eye 49
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Many models that seek to explain the origin of the unresolved X-ray background predict that Compton-thick Active Galactic Nuclei (AGNs) are ubiquitious at high redshift. However, few distant Compton-thick AGNs have been reliably identified to date. Here we present Spitzer-IRS spectroscopy and 3.6-70um photometry of a z=2.2 optically identified AGN (HDF-oMD49) that is formally undetected in the 2Ms Chandra Deep Field-North (CDF-N) survey. The Spitzer-IRS spectrum and spectral energy distribution...
Source: http://arxiv.org/abs/0803.0636v4
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116
Jul 20, 2013
07/13
by
E. A. Richards; F. E. Bauer; A. J. Barger; L. Cowie
texts
eye 116
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Using a combination of radio and optical imaging at 0.1\arcs to 0.2\arcs resolution with the VLA/MERLIN and HST has led to a breakthrough in our understanding of radio emission from distant (0.1 4-6) and submillimeter sources with S > 2 mJy at 850 microns as measured with SCUBA on the JCMT. The far-infrared luminosities of these galaxies exceeds even the most intense starbursts found in the local universe (e.g., Arp 220), suggesting they are in the process of converting the bulk of their...
Source: http://arxiv.org/abs/astro-ph/9910497v2
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28
Sep 20, 2013
09/13
by
E. D. Feigelson; A. E. Hornschemeier; G. Micela; F. E. Bauer; D. M. Alexander; W. N. Brandt; F. Favata; S. Sciortino; G. P. Garmire; Penn State; Johns Hopkins; Palermo; Cambridge; ESTEC
texts
eye 28
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The extremely sensitive Chandra Deep Field-North (CDF-N) pencil-beam X-ray survey is used to identify and characterize the X-ray emission from old high-latitude main sequence Galactic stars. Our principal goal is to investigate the expected long-term decay of magnetic activity of late-type stars due to the gradual spindown of stellar rotation from a magnetized stellar wind. Eleven X-ray sources constitute a well-defined sample of 2 G, 2 K0-K4, and 7 M2-M5 stars with median distance around 300...
Source: http://arxiv.org/abs/astro-ph/0405026v1
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46
Sep 18, 2013
09/13
by
E. Daddi; D. M. Alexander; M. Dickinson; R. Gilli; A. Renzini; D. Elbaz; A. Cimatti; R. Chary; D. Frayer; F. E. Bauer; W. N. Brandt; M. Giavalisco; N. A. Grogin; M. Huynh; J. Kurk; M. Mignoli; G. Morrison; A. Pope; S. Ravindranath
texts
eye 46
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Approximately 20-30% of 1.46.2 keV. The stacked X-ray spectrum rises steeply at >10 keV, suggesting that these sources host Compton-thick Active Galactic Nuclei (AGNs) with column densities N_H~10^{24} cm^-2 and an average, unobscured X-ray luminosity L_{2-8 keV}~(1-4)x10^43 erg/s. Their sky density(~3200 deg^-2) and space density (~2.6x10^-4 Mpc^-3) are twice those of X-ray detected AGNs at z~2, and much larger than those of previously-known Compton thick sources at similar redshifts. The...
Source: http://arxiv.org/abs/0705.2832v2
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50
Sep 18, 2013
09/13
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E. Daddi; M. Dickinson; G. Morrison; R. Chary; A. Cimatti; D. Elbaz; D. Frayer; A. Renzini; A. Pope; D. M. Alexander; F. E. Bauer; M. Giavalisco; M. Huynh; J. Kurk; M. Mignoli
texts
eye 50
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Examining a sample of massive galaxies at 1.410^{11}L_sun, show a mid-IR excess which is likely due to the presence of obscured active nuclei, as shown in a companion paper. There is a tight and roughly linear correlation between stellar mass and SFR for 24um-detected galaxies. For a given mass, the SFR at z=2 was larger by a factor of ~4 and ~30 relative to that in star forming galaxies at z=1 and z=0, respectively. Typical ultraluminous infrared galaxies (ULIRGs) at z=2 are relatively...
Source: http://arxiv.org/abs/0705.2831v2
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51
Sep 19, 2013
09/13
by
E. Daddi; M. Dickinson; R. Chary; A. Pope; G. Morrison; D. M. Alexander; F. E. Bauer; W. N. Brandt; M. Giavalisco; H. Ferguson; K. -S. Lee; C. Papovich; A. Renzini
texts
eye 51
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We investigate the multi-wavelength emission of BzK selected star forming galaxies at z~2 in the Great Observatories Origins Deep Survey (GOODS) North region. Most (82%) of the sources are individually detected at 24um in the Spitzer MIPS imaging, and one fourth (26%) in the VLA radio data. Significant detections of the individually undetected objects are obtained through stacking in the radio, submm and X-ray domains. The typical star forming galaxy with stellar mass ~10^{11}Mo at z=2 is an...
Source: http://arxiv.org/abs/astro-ph/0507504v1
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65
Sep 23, 2013
09/13
by
F. E. Bauer; D. M. Alexander; W. N. Brandt; D. P. Schneider; E. Treister; A. E. Hornschemeier; G. P. Garmire
texts
eye 65
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We investigate the X-ray number counts in the 1-2 Ms Chandra Deep Fields (CDFs) to determine the contributions of faint X-ray source populations to the extragalactic X-ray background (XRB). X-ray sources were separated into Active Galactic Nuclei (AGN), star-forming galaxies, and Galactic stars based on several criteria. We find that AGN continue to dominate the number counts in the 0.5-2.0 keV and 2-8 keV bands. At flux limits of ~2.5e-17 erg cm-2 s-1 (0.5-2.0 keV) and ~1.4e-16 erg cm-2 s-1...
Source: http://arxiv.org/abs/astro-ph/0408001v2
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16
Jun 28, 2018
06/18
by
G. B. Lansbury; P. Gandhi; D. M. Alexander; R. J. Assef; J. Aird; A. Annuar; D. R. Ballantyne; M. Balokovic; F. E. Bauer; S. E. Boggs; W. N. Brandt; M. Brightman; F. E. Christensen; F. Civano; A. Comastri; W. W. Craig; A. Del Moro; B. W. Grefenstette; C. J. Hailey; F. A. Harrison; R. C. Hickox; M. Koss; S. M. LaMassa; B. Luo; S. Puccetti; D. Stern; E. Treister; C. Vignali; L. Zappacosta; W. W. Zhang
texts
eye 16
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The intrinsic column density (NH) distribution of quasars is poorly known. At the high obscuration end of the quasar population and for redshifts z 1.5e24 cm^-2) type 2 quasars (CTQSO2s); five new NuSTAR observations are reported herein, and four have been previously published. The candidate CTQSO2s lie at z ~ 90 net source counts at 8-24 keV). For these NuSTAR-detected sources direct (i.e., X-ray spectral) constraints on the intrinsic AGN properties are feasible, and we measure column...
Topics: High Energy Astrophysical Phenomena, Astrophysics, Astrophysics of Galaxies
Source: http://arxiv.org/abs/1506.05120
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45
Sep 19, 2013
09/13
by
J. D. Silverman; V. Mainieri; M. Salvato; G. Hasinger; J. Bergeron; P. Capak; G. Szokoly; A. Finoguenov; R. Gilli; P. Rosati; P. Tozzi; C. Vignali; D. M. Alexander; W. N. Brandt; B. D. Lehmer; B. Luo; D. Rafferty; Y. Q. Xue; I. Balestra; F. E. Bauer; M. Brusa; A. Comastri; J. Kartaltepe; A. M. Koekemoer; T. Miyaji; D. P. Schneider; E. Treister; L. Wisotski; M. Schramm
texts
eye 45
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We present the results of a program to acquire high-quality optical spectra of X-ray sources detected in the E-CDF-S and its central area. New spectroscopic redshifts are measured for 283 counterparts to Chandra sources with deep exposures (t~2-9 hr per pointing) using multi-slit facilities on both the VLT and Keck thus bringing the total number of spectroscopically-identified X-ray sources to over 500 in this survey field. We provide a comprehensive catalog of X-ray sources detected in the...
Source: http://arxiv.org/abs/1009.1923v1
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58
Sep 21, 2013
09/13
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J. R. Mullaney; M. Pannella; E. Daddi; D. M. Alexander; D. Elbaz; R. C. Hickox; F. Bournaud; B. Altieri; H. Aussel; D. Coia; H. Dannerbauer; K. Dasyra; M. Dickinson; H. S. Hwang; J. Kartaltepe; R. Leiton; G. Magdis; B. Magnelli; P. Popesso; I. Valtchanov; F. E. Bauer; W. N. Brandt; A. Del Moro; D. J. Hanish; R. J. Ivison; S. Juneau; B. Luo; D. Lutz; M. T. Sargent; D. Scott; Y. Q. Xue
texts
eye 58
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We present a study of the infrared properties of X-ray selected, moderate luminosity (Lx=10^{42}-10^{44}ergs/s) active galactic nuclei (AGNs) up to z~3, to explore the links between star formation in galaxies and accretion onto their central black holes. We use 100um and 160um fluxes from GOODS-Herschel -the deepest survey yet undertaken by the Herschel telescope- and show that in >94 per cent of cases these fluxes are dominated by the host. We find no evidence of any correlation between the...
Source: http://arxiv.org/abs/1106.4284v3
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13
Jun 26, 2018
06/18
by
M. Brightman; M. Balokovic; D. Stern; P. Arevalo; D. R. Ballantyne; F. E. Bauer; S. E. Boggs; W. W. Craig; F. E. Christensen; A. Comastri; F. Fuerst; P. Gandhi; C. J. Hailey; F. A. Harrison; R. C. Hickox; M. Koss; S. LaMassa; S. Puccetti; E. Rivers; R. Vasudevan; D. J. Walton; W. W. Zhang
texts
eye 13
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The covering factor of Compton-thick obscuring material associated with the torus in active galactic nuclei (AGN) is at present best understood through the fraction of sources exhibiting Compton-thick absorption along the line of sight ($N_{H}>1.5\times10^{24}$ cm$^{-2}$) in the X-ray band, which reveals the average covering factor. Determining this Compton-thick fraction is difficult however, due to the extreme obscuration. With its spectral coverage at hard X-rays ($>$10 keV), NuSTAR is...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1502.07353
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16
Jun 27, 2018
06/18
by
M. Nicholl; S. J. Smartt; A. Jerkstrand; C. Inserra; S. A. Sim; T. -W. Chen; S. Benetti; M. Fraser; A. Gal-Yam; E. Kankare; K. Maguire; K. Smith; M. Sullivan; S. Valenti; D. R. Young; C. Baltay; F. E. Bauer; S. Baumont; D. Bersier; M. -T. Botticella; M. Childress; M. Dennefeld; M. Della Valle; N. Elias-Rosa; U. Feindt; L. Galbany; E. Hadjiyska; L. Le Guillou; G. Leloudas; P. Mazzali; R. McKinnon; J. Polshaw; D. Rabinowitz; S. Rostami; R. Scalzo; B. P. Schmidt; S. Schulze; J. Sollerman; F....
texts
eye 16
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We assemble a sample of 24 hydrogen-poor super-luminous supernovae (SLSNe). Parameterizing the light curve shape through rise and decline timescales shows that the two are highly correlated. Magnetar-powered models can reproduce the correlation, with the diversity in rise and decline rates driven by the diffusion timescale. Circumstellar interaction models can exhibit a similar rise-decline relation, but only for a narrow range of densities, which may be problematic for these models. We find...
Topics: Solar and Stellar Astrophysics, Astrophysics, High Energy Astrophysical Phenomena, Cosmology and...
Source: http://arxiv.org/abs/1503.03310
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11
Jun 27, 2018
06/18
by
Michael J. Koss; C. Romero-Canizales; L. Baronchelli; S. H. Teng; M. Balokovic; S. Puccetti; F. E. Bauer; P. Arevalo; R. Assef; D. R. Ballantyne; W. N. Brandt; M. Brightman; A. Comastri; P. Gandhi; F. A. Harrison; B. Luo; K. Schawinski; D. Stern; E. Treister
texts
eye 11
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We present new NuSTAR and Chandra observations of NGC 3393, a galaxy reported to host the smallest separation dual AGN resolved in the X-rays. While past results suggested a 150 pc separation dual AGN, three times deeper Chandra imaging, combined with adaptive optics and radio imaging suggest a single, heavily obscured, radio-bright AGN. Using VLA and VLBA data, we find an AGN with a two-sided jet rather than a dual AGN and that the hard X-ray, UV, optical, NIR, and radio emission are all from...
Topics: High Energy Astrophysical Phenomena, Astrophysics, Astrophysics of Galaxies
Source: http://arxiv.org/abs/1505.03524
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44
Sep 19, 2013
09/13
by
N. A. Grogin; C. J. Conselice; E. Chatzichristou; D. M. Alexander; F. E. Bauer; A. E. Hornschemeier; S. Jogee; A. M. Koekemoer; V. G. Laidler; M. Livio; R. A. Lucas; M. Paolillo; S. Ravindranath; E. J. Schreier; B. D. Simmons; C. M. Urry
texts
eye 44
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We investigate morphological structure parameters and local environments of distant moderate-luminosity active galactic nucleus (AGN) host galaxies in the overlap between the HST/ACS observations of the Great Observatories Origins Deep Survey (GOODS) and the two Chandra Deep Fields. We compute near-neighbor counts and BViz asymmetry (A) and concentration (C) indices for ~35,500 GOODS/ACS galaxies complete to z_850 ~ 26.6, including the resolved hosts of 322 X-ray-selected AGNs. Distributions of...
Source: http://arxiv.org/abs/astro-ph/0507091v1
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42
Sep 18, 2013
09/13
by
P. Santini; D. J. Rosario; L. Shao; D. Lutz; R. Maiolino; D. M. Alexander; B. Altieri; P. Andreani; H. Aussel; F. E. Bauer; S. Berta; A. Bongiovanni; W. N. Brandt; M. Brusa; J. Cepa; A. Cimatti; E. Daddi; D. Elbaz; A. Fontana; N. M. Forster Schreiber; R. Genzel; A. Grazian; E. Le Floc'h; B. Magnelli; V. Mainieri; R. Nordon; A. M. Perez Garcia; A. Poglitsch; P. Popesso; F. Pozzi; L. Riguccini; G. Rodighiero; M. Salvato; M. Sanchez-Portal; E. Sturm; L. J. Tacconi; I. Valtchanov; S. Wuyts
texts
eye 42
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We compare the average star formation (SF) activity in X-ray selected AGN hosts with mass-matched control inactive galaxies,including star forming and quiescent sources, at 0.510sigma) for bright AGNs. However, when comparing to star forming galaxies only, AGN hosts are broadly consistent with the locus of their `main sequence'. We investigate the relative far-IR luminosity distributions of active and inactive galaxies, and find a higher fraction of PACS detected, hence normal and highly star...
Source: http://arxiv.org/abs/1201.4394v3
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44
Sep 18, 2013
09/13
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R. M. Bandyopadhyay; J. C. A. Miller-Jones; K. M. Blundell; F. E. Bauer; Ph. Podsiadlowski; A. J. Gosling; Q. D. Wang; E. Pfahl; S. Rappaport
texts
eye 44
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We present near-IR imaging of a sample of the faint, hard X-ray sources discovered in the 2001 Chandra ACIS-I survey towards the Galactic Centre (GC) (Wang et al. 2002). These ~800 discrete sources represent an important and previously undetected population within the Galaxy. From our VLT observations of 77 X-ray sources, we identify candidate K-band counterparts to 75% of the Chandra sources in our sample. The near-IR magnitudes and colours of the majority of candidate counterparts are...
Source: http://arxiv.org/abs/astro-ph/0509346v1
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35
Sep 22, 2013
09/13
by
R. M. Bandyopadhyay; J. C. A. Miller-Jones; K. M. Blundell; F. E. Bauer; Ph. Podsiadlowski; Q. D. Wang; S. Rappaport; E. Pfahl
texts
eye 35
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We present results from the first near-IR imaging of the weak X-ray sources discovered in the Chandra/ACIS-I survey (Wang et al. 2002) towards the Galactic Centre (GC). These ~800 discrete sources, which contribute significantly to the GC X-ray emission, represent an important and previously unknown population within the Galaxy. From our VLT observations we will identify likely IR counterparts to a sample of the hardest sources, which are most likely X-ray binaries. With these data we can place...
Source: http://arxiv.org/abs/astro-ph/0501327v1
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129
Sep 17, 2013
09/13
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W. N. Brandt; D. M. Alexander; A. E. Hornschemeier; G. P. Garmire; D. P. Schneider; A. J. Barger; F. E. Bauer; P. S. Broos; L. L. Cowie; L. K. Townsley; D. N. Burrows; G. Chartas; E. D. Feigelson; R. E. Griffiths; J. A. Nousek; W. L. W. Sargent
texts
eye 129
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An extremely deep X-ray survey (about 1 Ms) of the Hubble Deep Field North and its environs (about 450 arcmin^2) has been performed with the Advanced CCD Imaging Spectrometer on board the Chandra X-ray Observatory. This is one of the two deepest X-ray surveys ever performed; for point sources near the aim point it reaches 0.5-2.0 keV and 2-8 keV flux limits of 3 x 10^{-17} erg/cm^2/s and 2 x 10^{-16} erg/cm^2/s, respectively. Here we provide source catalogs along with details of the...
Source: http://arxiv.org/abs/astro-ph/0108404v1
