- ID:
- ivo://CDS.VizieR/J/ApJ/818/182
- Title:
- Early-type galaxies at z<0.04 star formation rates
- Short Name:
- J/ApJ/818/182
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We address the relation between star formation and active galactic nucleus (AGN) activity in a sample of 231 nearby (0.0002<z<0.0358) early-type galaxies by carrying out a multi-wavelength study using archival observations in the UV, IR, and radio. Our results indicate that early-type galaxies in the current epoch are rarely powerful AGNs, with P<10^22^W/Hz for a majority of the galaxies. Only massive galaxies are capable of hosting powerful radio sources while less massive galaxies are hosts to lower radio power sources. Evidence of ongoing star formation is seen in approximately 7% of the sample. The star formation rate (SFR) of these galaxies is less than 0.1M_{sun}_/yr. They also tend to be radio faint (P<10^22^W/Hz). There is a nearly equal fraction of star-forming galaxies in radio faint (P<10^22^W/Hz) and radio bright galaxies (P>=10^22^W/Hz) suggesting that both star formation and radio mode feedback are constrained to be very low in our sample. We notice that our galaxy sample and the Brightest Cluster Galaxies follow similar trends in radio power versus SFR. This may be produced if both radio power and SFR are related to stellar mass.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/796/60
- Title:
- ECDFS galaxies photometric redshifts & counterparts
- Short Name:
- J/ApJ/796/60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present photometric redshifts and associated probability distributions for all detected sources in the Extended Chandra Deep Field South (ECDFS). This work makes use of the most up-to-date data from the Cosmic Assembly Near-IR Deep Legacy Survey (CANDELS) and the Taiwan ECDFS Near-Infrared Survey (TENIS) in addition to other data. We also revisit multi-wavelength counterparts for published X-ray sources from the 4Ms CDFS and 250ks ECDFS surveys, finding reliable counterparts for 1207 out of 1259 sources (~96%). Data used for photometric redshifts include intermediate-band photometry deblended using the TFIT method, which is used for the first time in this work. Photometric redshifts for X-ray source counterparts are based on a new library of active galactic nuclei/galaxy hybrid templates appropriate for the faint X-ray population in the CDFS. Photometric redshift accuracy for normal galaxies is 0.010 and for X-ray sources is 0.014 and outlier fractions are 4% and 5.2%, respectively. The results within the CANDELS coverage area are even better, as demonstrated both by spectroscopic comparison and by galaxy-pair statistics. Intermediate-band photometry, even if shallow, is valuable when combined with deep broadband photometry. For best accuracy, templates must include emission lines.
- ID:
- ivo://CDS.VizieR/J/ApJ/642/L13
- Title:
- ECDFS MUSYC galaxies UBVRIzNB5000 photometry
- Short Name:
- J/ApJ/642/L13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We selected 40 candidate Ly{alpha}-emitting galaxies (LAEs) at z~3.1 with observed-frame equivalent widths greater than 150{AA} and inferred emission-line fluxes above 2.5x10^-17^ergs/cm^2^/s from deep narrowband and broadband MUSYC images of the Extended Chandra Deep Field South. Covering 992-arcmin^2^, this is the largest "blank field" surveyed for LAEs at z~3, allowing an improved estimate of the space density of this population of (3+/-1)x10^4^h/Mpc^3^. Spectroscopic follow-up of 23 candidates yielded 18 redshifts, all at z~3.1. Over 80% of the LAEs are dimmer in continuum magnitude than the typical Lyman break galaxy (LBG) spectroscopic limit of R=25.5 (AB), with a median continuum magnitude R~27 and very blue continuum colors, V-z~=0.
- ID:
- ivo://CDS.VizieR/J/A+A/506/501
- Title:
- Eclipsing binaries in CoRoT-LRc01 field
- Short Name:
- J/A+A/506/501
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present here the list of planetary transit candidates detected in the first long run observed by CoRoT: LRc01, towards the galactic center in the direction of Aquila, which lasted from May to October 2007. We analyzed 3719 (33%) sources in the chromatic bands and 7689 in the monochromatic band. Instrumental noise and the stellar variability were treated with several detrending tools, on which subsequently several transit search algorithms were applied. Forty two sources were classified as planetary transit candidates and up to now 26 cases have been solved. One planet (CoRoT-2b) and one brown-dwarf (CoRoT-3b) have been the subjects of detailed publications.
- ID:
- ivo://CDS.VizieR/J/ApJ/831/89
- Title:
- Eclipsing LMXB at the center of 3FGL J0427.9-6704
- Short Name:
- J/ApJ/831/89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of an eclipsing low-mass X-ray binary at the center of the 3FGL error ellipse of the unassociated Fermi/Large Area Telescope {gamma}-ray source 3FGL J0427.9-6704. Photometry from OGLE and the SMARTS 1.3m telescope and spectroscopy from the SOAR telescope have allowed us to classify the system as an eclipsing low-mass X-ray binary (P=8.8hr) with a main-sequence donor and a neutron-star accretor. Broad double-peaked H and He emission lines suggest the ongoing presence of an accretion disk. Remarkably, the system shows separate sets of absorption lines associated with the accretion disk and the secondary, and we use their radial velocities to find evidence for a massive (~1.8-1.9M_{sun}_) neutron-star primary. In addition to a total X-ray eclipse with a duration of ~2200s observed with NuSTAR, the X-ray light curve also shows properties similar to those observed among known transitional millisecond pulsars: short-term variability, a hard power-law spectrum ({Gamma}~1.7), and a comparable 0.5-10keV luminosity (~2.4x10^33^erg/s). We find tentative evidence for a partial (~60%) {gamma}-ray eclipse at the same phase as the X-ray eclipse, suggesting the {gamma}-ray emission may not be confined to the immediate region of the compact object. The favorable inclination of this binary is promising for future efforts to determine the origin of {gamma}-rays among accreting neutron stars.
- ID:
- ivo://CDS.VizieR/J/A+A/492/637
- Title:
- Eddington ratios of faint AGN
- Short Name:
- J/A+A/492/637
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use one of the deepest spectroscopic samples of broad-line active galactic nuclei (AGN) currently available, extracted from the VIMOS VLT Deep Survey (VVDS, Cat. <III/250>), to compute the MgII and CIV virial-mass estimates of 120 super-massive black holes in the redshift range 1.0<z<1.9 and 2.6<z<4.3.
- ID:
- ivo://CDS.VizieR/J/A+A/391/1039
- Title:
- Effective temperature of metal-poor A-type stars
- Short Name:
- J/A+A/391/1039
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Effective temperatures (T_eff_) can be determined from (V-J)_0_, (V-H)_0_ and (V-K)_0_ colours that are derived from 2MASS magnitudes. This gives another way to estimate the T_eff_ of faint blue halo stars (V<~15) whose temperatures are now usually deduced from (B_V)_0_. Transformations (adapted from Carpenter, 2001AJ....121.2851C) are used to change colours derived from the 2MASS data to the Johnson system. T_eff_ is then derived from these colours using an updated Kurucz model. Tables are given to derive T_eff_ as a function of (V-J)_0_, (V-H)_0_ and (V-K)_0_ for a variety of metallicities and suitable for blue horizontal branch and main sequence stars. The temperatures obtained in this way are compared with those in the recent literature for various stars with 5<=V<=15 and T_eff_ in the range 6500 to 9500K; systematic differences are ~100K. An exception is the sample of BHB stars observed by Wilhelm et al. (1999, Cat. <J/AJ/117/2329>) whose T_eff_ are significantly cooler than those we derive by an amount that increases with increasing temperature. Description:
- ID:
- ivo://CDS.VizieR/J/A+A/450/735
- Title:
- Effective temperatures and radii of stars
- Short Name:
- J/A+A/450/735
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents a method to determine effective temperatures, angular semi-diameters and bolometric corrections for population I and II FGK type stars based on V and 2MASS IR photometry. Accurate calibration is accomplished by using a sample of solar analogues, whose average temperature is assumed to be equal to the solar effective temperature of 5777K.
- ID:
- ivo://CDS.VizieR/J/A+AS/129/505
- Title:
- Effective temperatures by Infrared Flux Method
- Short Name:
- J/A+AS/129/505
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Effective temperatures for 420 stars with spectral types between A0 and K3, and luminosity classes between II and V, selected for a flux calibration of the Infrared Space Observatory, ISO, have been determined using the Infrared Flux Method (IRFM). The determinations are based on narrow and wide band photometric data obtained for this purpose, and take into account previously published narrow-band measures of temperature.
- ID:
- ivo://CDS.VizieR/J/AN/321/277
- Title:
- Effective temperatures of K-M giants
- Short Name:
- J/AN/321/277
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A high-resolution spectroscopic survey in the 6380-6460{AA} region of 224 slowly-rotating M-K class III giants is presented. Spectral line-depth ratio are calibrated against effective temperature obtained from B-V and V-I color indices in the range 3200-7500K (M6-A9). A table of polynomial coefficients for 12 line-ratio-Teff relations can be used to derive Teff of F-M stars to within 33K (rms), and of early-F and mid-to-late M stars to within 77-106K (rms).
