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- ID:
- ivo://CDS.VizieR/J/ApJ/734/43
- Title:
- X-ray, optical and radio monitoring of 3C 111
- Short Name:
- J/ApJ/734/43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of extensive multi-frequency monitoring of the radio galaxy 3C 111 between 2004 and 2010 at X-ray (2.4-10keV), optical (R band), and radio (14.5, 37, and 230GHz) wave bands, as well as multi-epoch imaging with the Very Long Baseline Array (VLBA) at 43GHz. Over the six years of observation, significant dips in the X-ray light curve are followed by ejections of bright superluminal knots in the VLBA images. This shows a clear connection between the radiative state near the black hole, where the X-rays are produced, and events in the jet. The X-ray continuum flux and Fe line intensity are strongly correlated, with a time lag shorter than 90 days and consistent with zero.
- ID:
- ivo://CDS.VizieR/J/PASJ/56/965
- Title:
- X-ray properties of ASCA objects
- Short Name:
- J/PASJ/56/965
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Utilizing ASCA archival data of about 300 objects of elliptical galaxies, groups, and clusters of galaxies, we performed systematic measurements of the X-ray properties of hot gas in their systems, and compiled them in this paper. The steepness of the luminosity-temperature (LT) relation, L_X_{prop.to}(kT)^alpha^, in the range of kT~1.5-15keV is alpha=3.17+/-0.15, consistent with previous measurements.
- ID:
- ivo://CDS.VizieR/J/MNRAS/428/3089
- Title:
- X-ray properties of BzK-selected galaxies
- Short Name:
- J/MNRAS/428/3089
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the X-ray properties of BzK-selected galaxies at z~2 using deep X-ray data in the Chandra Deep Field-South (CDFS) and Chandra Deep Field-North (CDFN). A subset of these BzK galaxies have been proposed as Compton-thick active galactic nucleus (AGN) candidates based on a high ratio of infrared (IR) to ultraviolet (UV) star formation rates (SFRs). With the benefit of deep 24{mu}m observations, our sample of these IR-excess galaxies is larger than previous studies and combined with the deepest X-ray data yield new insights into the population. We identify 701 and 534 star-forming BzK galaxies (sBzK galaxies) in the range z=1.2-3.0 in CDFS and CDFN, respectively. Of these we directly detect in X-rays 49 sBzK galaxies in CDFS and 32 sBzK galaxies in CDFN.
- ID:
- ivo://CDS.VizieR/J/A+A/501/485
- Title:
- X-ray properties of Chandra red galaxies
- Short Name:
- J/A+A/501/485
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the X-ray properties of the extremely red objects (ERO) population observed by Chandra with three partially overlapping pointings (up to ~90ks) over an area of ~500arcmin^2^, down to a 0.5-8keV flux limit of ~10-15erg/cm^2^/s. We selected EROs using a multi-band photometric catalog down to a Ks-band magnitude of ~19.3 (Vega system); 14 EROs were detected in X-rays, corresponding to ~9% of the overall X-ray source population (149 X-ray sources) and to ~5% of the ERO population (288). The X-ray emission of all X-ray detected EROs is consistent with that of an active galactic nucleus (AGN) (>~3.5x10^42^erg/s at photometric redshifts z>1), in agreement with previous X-ray observations, with an indication of increasing absorption between the three X-ray brightest EROs and the 11 X-ray faintest EROs.
- ID:
- ivo://CDS.VizieR/J/MNRAS/422/494
- Title:
- X-ray properties of optically selected ETGs
- Short Name:
- J/MNRAS/422/494
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the X-ray properties of 393 optically selected early-type galaxies (ETGs) over the redshift range of z~~0.0-1.2 in the Chandra Deep Fields (CDFs). To measure the average X-ray properties of the ETG population, we use X-ray stacking analyses with a subset of 158 passive ETGs (148 of which were individually undetected in X-ray). This ETG subset was constructed to span the redshift ranges of z=0.1-1.2 in the ~~4Ms CDF-South and ~~2Ms CDF-North and z=0.1-0.6 in the ~~250ks Extended-CDF-South where the contribution from individually undetected active galactic nuclei (AGN) is expected to be negligible in our stacking.
- ID:
- ivo://CDS.VizieR/J/ApJ/713/L11
- Title:
- X-ray properties of Seyfert 1 galaxies
- Short Name:
- J/ApJ/713/L11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use publicly available XMM-Newton data to systematically compare the hard X-ray photon indices, {Gamma}_2-10keV_, and the iron K{alpha} emission lines of narrow- and broad-line Seyfert 1 (NLS1 and BLS1) galaxies. We compile a flux-limited (f_2-10keV_>=1x10^-12^erg/s/cm^2^) sample including 114 radio-quiet objects, with the 2-10keV luminosity ranging from 10^41^ to 10^45^erg/s. 86 out of these 114 AGNs are included in the CAIXA catalogue (Bianchi et al. 2009, Cat. J/A+A/495/421). The redshift range of the present sample is z<0.37, with only seven objects having z>0.2.
- ID:
- ivo://CDS.VizieR/J/MNRAS/396/2011
- Title:
- X-ray+Radio sources in XBootes
- Short Name:
- J/MNRAS/396/2011
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- With the goal of investigating the nature and the environment of the faint radio sources (at mJy level), here are presented results of X-ray identifications of Faint Imaging Radio Survey at Twenty centimetres (FIRST) in the 9deg^2^ Bootes field of the National Optical Astronomy Observatory (NOAO) Deep Wide Field Survey (NDWFS), using data from the Chandra XBootes survey. A total of 92 (10 per cent) FIRST radio sources are identified above the X-ray flux limit f_X_)(0.5-7)keV=8x10^-15^erg/s/cm^2^, and 79 optical counterparts are common to both the radio and X-ray sources. Spectroscopic identifications [obtained from the Sloan Digital Sky Survey (SDSS) survey] were available for 22 sources (27 per cent).
- ID:
- ivo://CDS.VizieR/J/MNRAS/360/782
- Title:
- X-ray-selected normal galaxies
- Short Name:
- J/MNRAS/360/782
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we estimate the local (z<0.22) X-ray luminosity function of 'normal' galaxies derived from the XMM-Newton Needles in the Haystack Survey. This is an on-going project that aims to identify X-ray-selected normal galaxies (i.e. non-AGN dominated) in the local Universe. We are using a total of 70 XMM-Newton fields covering an area of 11deg^2^ which overlap with the Sloan Digital Sky Survey Data Release 2. Normal galaxies are selected on the basis of their resolved optical light profile, their low X-ray-to-optical flux ratio [log(fx/fo)<-2] and soft X-ray colours. We find a total of 28 candidate normal galaxies to the 0.58keV band flux limit of 2x10^-15^erg/cm2/s. Optical spectra are available for most sources in our sample (82 per cent). These provide additional evidence that our sources are bona fide normal galaxies with X-ray emission coming from diffuse hot gas emission and/or X-ray binaries rather than a supermassive black hole.
- ID:
- ivo://CDS.VizieR/J/ApJ/797/91
- Title:
- X-Ray source properties for NGC 2207/IC 2163
- Short Name:
- J/ApJ/797/91
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a comprehensive study of the total X-ray emission from the colliding galaxy pair NGC 2207/IC 2163, based on Chandra, Spitzer, and GALEX data. We detect 28 ultraluminous X-ray sources (ULXs), 7 of which were not detected previously because of X-ray variability. Twelve sources show significant long-term variability, with no correlated spectral changes. Seven sources are transient candidates. One ULX coincides with an extremely blue star cluster (B-V=-0.7). We confirm that the global relation between the number and luminosity of ULXs and the integrated star-formation rate (SFR) of the host galaxy also holds on local scales. We investigate the effects of dust extinction and age on the X-ray binary (XRB) population on subgalactic scales. The distributions of N_X_ and L_X_ are peaked at L_IR_/L_NUV_~1, which may be associated with an age of ~10 Myr for the underlying stellar population. We find that approximately one-third of the XRBs are located in close proximity to young star complexes. The luminosity function of the XRBs is consistent with that typical for high-mass XRBs and appears unaffected by variability. We disentangle and compare the X-ray diffuse spectrum with that of the bright XRBs. The hot interstellar medium dominates the diffuse X-ray emission at E<~1 keV and has a temperature kT=0.28_-0.04_^+0.05^ keV and intrinsic 0.5-2 keV luminosity of 7.9x10^40^ erg/s, a factor of ~2.3 higher than the average thermal luminosity produced per unit SFR in local star-forming galaxies. The total X-ray output of NGC 2207/IC 2163 is 1.5x10^41^ erg/s, and the corresponding total integrated SFR is 23.7 M_{sun}_/yr.
