43
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
favorite 0
comment 0
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
20
20
Jun 28, 2018
06/18
by
A. Annuar; P. Gandhi; D. M. Alexander; G. B. Lansbury; P. Arévalo; D. R. Ballantyne; M. Baloković; F. E. Bauer; S. E. Boggs; W. N. Brandt; M. Brightman; F. E. Christensen; W. W. Craig; A. Del Moro; C. J. Hailey; F. A. Harrison; R. C. Hickox; G. Matt; S. Puccetti; C. Ricci; J. R. Rigby; D. Stern; D. J. Walton; L. Zappacosta; W. Zhang
texts
eye 20
favorite 0
comment 0
We present two NuSTAR observations of the local Seyfert 2 active galactic nucleus (AGN) and an ultraluminous X-ray source (ULX) candidate in NGC 5643. Together with archival data from Chandra, XMM-Newton and Swift-BAT, we perform a high-quality broadband spectral analysis of the AGN over two decades in energy ($\sim$0.5-100 keV). Previous X-ray observations suggested that the AGN is obscured by a Compton-thick (CT) column of obscuring gas along our line-of-sight. However, the lack of...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1509.03322
37
37
Sep 23, 2013
09/13
by
A. Comastri; P. Ranalli; K. Iwasawa; C. Vignali; R. Gilli; I. Georgantopoulos; X. Barcons; W. N. Brandt; H. Brunner; M. Brusa; N. Cappelluti; F. J. Carrera; F. Civano; F. Fiore; G. Hasinger; V. Mainieri; A. Merloni; F. Nicastro; M. Paolillo; S. Puccetti; P. Rosati; J. D. Silverman; P. Tozzi; G. Zamorani; I. Balestra; F. E. Bauer; B. Luo; Y. Q. Xue
texts
eye 37
favorite 0
comment 0
We present the first results of the spectroscopy of distant, obscured AGN as obtained with the ultra-deep (~3.3 Ms) XMM-Newton survey in the Chandra Deep Field South (CDFS). One of the primary goals of the project is to characterize the X-ray spectral properties of obscured and heavily obscured Compton-thick AGN over the range of redhifts and luminosities that are relevant in terms of their contribution to the X-ray background. The ultra-deep exposure, coupled with the XMM detector's spectral...
Source: http://arxiv.org/abs/1012.4011v2
49
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
favorite 0
comment 0
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
12
12
Jun 26, 2018
06/18
by
A. Finoguenov; M. Tanaka; M. Cooper; V. Allevato; N. Cappelluti; A. Choi; C. Heymans; F. E. Bauer; F. Ziparo; P. Ranalli; J. Silverman; W. N. Brandt; Y. Q. Xue; J. Mulchaey; L. Howes; C. Schmid; D. Wilman; A. Comastri; G. Hasinger; V. Mainieri; B. Luo; P. Tozzi; P. Rosati; P. Capak; P. Popesso
texts
eye 12
favorite 0
comment 0
Ultra-deep observations of ECDF-S with Chandra and XMM-Newton enable a search for extended X-ray emission down to an unprecedented flux of $2\times10^{-16}$ ergs s$^{-1}$ cm$^{-2}$. We present the search for the extended emission on spatial scales of 32$^{\prime\prime}$ in both Chandra and XMM data, covering 0.3 square degrees and model the extended emission on scales of arcminutes. We present a catalog of 46 spectroscopically identified groups, reaching a redshift of 1.6. We show that the...
Topics: Cosmology and Nongalactic Astrophysics, Astrophysics, Astrophysics of Galaxies, High Energy...
Source: http://arxiv.org/abs/1501.03506
42
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
favorite 0
comment 0
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
44
44
Sep 20, 2013
09/13
by
A. J. Barger; L. L. Cowie; P. Capak; D. M. Alexander; F. E. Bauer; W. N. Brandt; G. P. Garmire; A. E. Hornschemeier
texts
eye 44
favorite 0
comment 0
Deep Chandra X-ray exposures provide an efficient route for locating optically faint active galactic nuclei (AGN) at high redshifts. We use deep multicolor optical data to search for z>5 AGN in the 2 Ms X-ray exposure of the Chandra Deep Field-North. Of the 423 X-ray sources bright enough (z' 6. The z>5 object is spectroscopically confirmed at z=5.19. Only 31 of the 77 sources with z'>25.2 are undetected in the B or V bands at the 2-sigma level and could lie at z>5. There are too...
Source: http://arxiv.org/abs/astro-ph/0301232v1
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
favorite 0
comment 0
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
49
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
favorite 0
comment 0
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
48
48
Sep 20, 2013
09/13
by
B. D. Lehmer; W. N. Brandt; D. M. Alexander; F. E. Bauer; D. P. Schneider; P. Tozzi; J. Bergeron; G. P. Garmire; R. Giacconi; R. Gilli; G. Hasinger; A. E. Hornschemeier; A. M. Koekemoer; V. Mainieri; T. Miyaji; M. Nonino; P. Rosati; J. D. Silverman; G. Szokoly; C. Vignali
texts
eye 48
favorite 0
comment 0
We present Chandra point-source catalogs for the Extended Chandra Deep Field-South (E-CDF-S) survey. The E-CDF-S consists of four contiguous 250 ks Chandra observations covering an approximately square region of total solid angle ~0.3 deg^2, which flank the existing ~1 Ms Chandra Deep Field-South (CDF-S). The survey reaches sensitivity limits of 1.1 X 10^-16 erg/cm^2/s and 6.7 X 10^-16 erg/cm^2/s for the 0.5-2.0 keV and 2-8 keV bands, respectively. We detect 762 distinct X-ray point sources...
Source: http://arxiv.org/abs/astro-ph/0506607v2
50
50
Sep 21, 2013
09/13
by
B. D. Lehmer; Y. Q. Xue; W. N. Brandt; D. M. Alexander; F. E. Bauer; M. Brusa; A. Comastri; R. Gilli; A. E. Hornschemeier; B. Luo; M. Paolillo; A. Ptak; O. Shemmer; D. P. Schneider; P. Tozzi; C. Vignali
texts
eye 50
favorite 0
comment 0
We present 0.5-2 keV, 2-8 keV, 4-8 keV, and 0.5-8 keV cumulative and differential number counts (logN-logS) measurements for the recently completed ~4 Ms Chandra Deep Field-South (CDF-S) survey, the deepest X-ray survey to date. We implement a new Bayesian approach, which allows reliable calculation of number counts down to flux limits that are factors of ~1.9-4.3 times fainter than the previously deepest number-counts investigations. In the soft band, the most sensitive bandpass in our...
Source: http://arxiv.org/abs/1204.1977v1
48
48
Sep 21, 2013
09/13
by
B. Luo; W. N. Brandt; J. D. Silverman; I. V. Strateva; F. E. Bauer; P. Capak; J. Kartaltepe; B. D. Lehmer; V. Mainieri; M. Salvato; G. Szokoly; D. P. Schneider; C. Vignali
texts
eye 48
favorite 0
comment 0
We report the discovery of the most-distant double-peaked emitter, CXOECDFS J033115.0-275518, at z=1.369. A Keck/DEIMOS spectrum shows a clearly double-peaked broad Mg II $\lambda2799$ emission line, with FWHM 11000 km/s for the line complex. The line profile can be well fit by an elliptical relativistic Keplerian disk model. This is one of a handful of double-peaked emitters known to be a luminous quasar, with excellent multiwavelength coverage and a high-quality X-ray spectrum. CXOECDFS...
Source: http://arxiv.org/abs/0901.2929v1
13
13
Jun 28, 2018
06/18
by
C. Vignali; K. Iwasawa; A. Comastri; R. Gilli; G. Lanzuisi; P. Ranalli; N. Cappelluti; V. Mainieri; I. Georgantopoulos; F. J. Carrera; J. Fritz; M. Brusa; W. N. Brandt; F. E. Bauer; F. Fiore; F. Tombesi
texts
eye 13
favorite 0
comment 0
In active galactic nuclei (AGN)-galaxy co-evolution models, AGN winds and outflows are often invoked to explain why super-massive black holes and galaxies stop growing efficiently at a certain phase of their lives. They are commonly referred to as the leading actors of feedback processes. Evidence of ultra-fast (v>0.05c) outflows in the innermost regions of AGN has been collected in the past decade by sensitive X-ray observations for sizable samples of AGN, mostly at low redshift. Here we...
Topics: High Energy Astrophysical Phenomena, Astrophysics, Astrophysics of Galaxies
Source: http://arxiv.org/abs/1509.05413
112
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
favorite 0
comment 0
(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
70
70
Sep 19, 2013
09/13
by
D. M. Alexander; F. E. Bauer; W. N. Brandt; D. P. Schneider; A. E. Hornschemeier; C. Vignali; A. J. Barger; P. S. Broos; L. L. Cowie; G. P. Garmire; L. K. Townsley; M. W. Bautz; G. Chartas; W. L. W. Sargent
texts
eye 70
favorite 0
comment 0
We present catalogs for the ~2 Ms Chandra Deep Field-North, currently the deepest X-ray observation of the Universe in the 0.5-8.0 keV band. Five hundred and three (503) X-ray sources are detected over an ~448 sq.arcmin area in up to seven bands; 20 of these X-ray sources lie in the Hubble Deep Field-North. Source positions are determined using matched-filter and centroiding techniques; the median positional uncertainty is ~0.3 arcsecs. The X-ray colors of the detected sources indicate a broad...
Source: http://arxiv.org/abs/astro-ph/0304392v1
28
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
favorite 0
comment 0
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
43
43
Sep 18, 2013
09/13
by
F. E. Bauer; C. Vignali; D. M. Alexander; W. N. Brandt; G. P. Garmire; A. E. Hornschemeier; P. Broos; L. Townsley; D. P. Schneider
texts
eye 43
favorite 0
comment 0
We briefly report here on our ongoing X-ray spectroscopy and variability analyses of 136 faint X-ray sources discovered in the 2 Ms Chandra Deep Field North observations spanning 1.4x10-15 to 2x10-13 ergs s-1 cm-2. Most sources are adequatley fitted with a simple intrinsic absorption plus power-law model, although the resulting photon index is much lower than the canonical average unabsorbed spectral slope found locally (suggesting additional spectral complexity). Among the 136 sources, 7% show...
Source: http://arxiv.org/abs/astro-ph/0210310v1
44
44
Sep 18, 2013
09/13
by
F. E. Bauer; C. Vignali; D. M. Alexander; W. N. Brandt; G. P. Garmire; A. E. Hornschemeier; P. S. Broos; L. K. Townsley; D. P. Schneider
texts
eye 44
favorite 0
comment 0
We investigate the nature of the faint X-ray source population through X-ray spectroscopy and variability analyses of 136 AGN detected in the 2 Ms Chandra Deep Field-North survey with > 200 background-subtracted 0.5-8.0 keV counts [F(0.5-8.0 keV)=(1.4-200)e-15 erg cm^{-2} s^{-1}]. Our preliminary spectral analyses yield median spectral parameters of Gamma=1.61 and intrinsic N_H=6.2e21 cm^{-2} (z=1 assumed when no redshift available) when the AGN spectra are fitted with a simple absorbed...
Source: http://arxiv.org/abs/astro-ph/0212389v1
12
12
Jun 28, 2018
06/18
by
F. Ursini; A. Marinucci; G. Matt; S. Bianchi; A. Tortosa; D. Stern; P. Arévalo; D. R. Ballantyne; F. E. Bauer; A. C. Fabian; F. A. Harrison; A. M. Lohfink; C. S. Reynolds; D. J. Walton
texts
eye 12
favorite 0
comment 0
We present an analysis of the 3-79 keV NuSTAR spectrum of the low-luminosity active galactic nucleus NGC 7213. In agreement with past observations, we find a lower limit to the high-energy cut-off of Ec > 140 keV, no evidence for a Compton-reflected continuum, and the presence of an iron Kalpha complex, possibly produced in the broad-line region. From the application of the MYTorus model, we find that the line-emitting material is consistent with the absence of a significant Compton...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1507.01775
16
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
favorite 0
comment 0
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
55
55
Sep 21, 2013
09/13
by
J. D. Silverman; V. Mainieri; B. D. Lehmer; D. M. Alexander; F. E. Bauer; J. Bergeron; W. N. Brandt; R. Gilli; G. Hasinger; D. P. Schneider; P. Tozzi; C. Vignali; A. M. Koekemoer; T. Miyaji; P. Popesso; P. Rosati; G. Szokoly
texts
eye 55
favorite 0
comment 0
We present an analysis of 109 moderate-luminosity (41.9 < Log L{0.5-8.0 keV} < 43.7) AGN in the Extended Chandra Deep Field-South survey, which is drawn from 5,549 galaxies from the COMBO-17 and GEMS surveys having 0.4 < z < 1.1. These obscured or optically-weak AGN facilitate the study of their host galaxies since the AGN provide an insubstantial amount of contamination to the galaxy light. We find that the color distribution of AGN host galaxies is highly dependent upon (1) the...
Source: http://arxiv.org/abs/0709.3455v2
45
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
favorite 0
comment 0
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
58
58
Sep 21, 2013
09/13
by
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
favorite 0
comment 0
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
13
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
favorite 0
comment 0
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
16
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
favorite 0
comment 0
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
53
53
Sep 18, 2013
09/13
by
M. P. Muno; F. E. Bauer; F. K. Baganoff; R. M. Bandyopadhyay; G. C. Bower; W. N. Brandt; P. S. Broos; A. Cotera; S. S. Eikenberry; G. P. Garmire; S. D. Hyman; N. E. Kassim; C. C. Lang; T. J. W. Lazio; C. Law; J. C. Mauerhan; M. R. Morris; T. Nagata; S. Nishiyama; S. Park; S. V. Ramirez; S. R. Stolovy; R. Wijnands; Q. D. Wang; Z. Wang; F. Yusef-Zadeh
texts
eye 53
favorite 0
comment 0
We present a catalog of 9017 X-ray sources identified in Chandra observations of a 2 by 0.8 degree field around the Galactic center. We increase the number of known X-ray sources in the region by a factor of 2.5. The catalog incorporates all of the ACIS-I observations as of 2007 August, which total 2.25 Msec of exposure. At the distance to the Galactic center (8 kpc), we are sensitive to sources with luminosities >4e32 erg/s (0.5-8.0 keV; 90% confidence) over an area of one square degree,...
Source: http://arxiv.org/abs/0809.1105v1
11
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
favorite 0
comment 0
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
42
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
favorite 0
comment 0
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
44
44
Sep 18, 2013
09/13
by
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
favorite 0
comment 0
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
35
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
favorite 0
comment 0
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
105
105
Sep 18, 2013
09/13
by
T. X. Thuan; F. E. Bauer; P. Papaderos; Y. I. Izotov
texts
eye 105
favorite 0
comment 0
We present an X-ray study of the three most metal-deficient blue compact dwarf (BCD) galaxies known in the local Universe, based on deep Chandra observations of SBS 0335-052 (0.025 solar abundance), SBS 0335-052W (0.02 solar abundance) and I Zw 18 (0.02 solar abundance). All three are detected, with more than 90% of their X-ray emission arising from point-like sources. The 0.5-10.0 keV luminosities of these point sources are in the range (1.3-8.5)x1e39 erg/s. We interpret them to be single or a...
Source: http://arxiv.org/abs/astro-ph/0401349v1
129
129
Sep 17, 2013
09/13
by
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
favorite 0
comment 0
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
57
57
Sep 23, 2013
09/13
by
Y. Q. Xue; B. Luo; W. N. Brandt; F. E. Bauer; B. D. Lehmer; P. S. Broos; D. P. Schneider; D. M. Alexander; M. Brusa; A. Comastri; A. C. Fabian; R. Gilli; G. Hasinger; A. E. Hornschemeier; A. Koekemoer; T. Liu; V. Mainieri; M. Paolillo; D. A. Rafferty; P. Rosati; O. Shemmer; J. D. Silverman; I. Smail; P. Tozzi; C. Vignali
texts
eye 57
favorite 1
comment 0
[abridged] We present point-source catalogs for the 4Ms Chandra Deep Field-South (CDF-S), which is the deepest Chandra survey to date and covers an area of 464.5 arcmin^2. We provide a main source catalog, which contains 740 X-ray point sources that are detected with wavdetect at a false-positive probability threshold of 1E-5 and also satisfy a binomial-probability source-selection criterion of P
Source: http://arxiv.org/abs/1105.5643v1
