- ID:
- ivo://CDS.VizieR/J/ApJ/872/192
- Title:
- A spectroscopic census of A2029 members
- Short Name:
- J/ApJ/872/192
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A rich spectroscopic census of members of the local massive cluster A2029 includes 1215 members of A2029 and its two infalling groups, A2033 and the Southern Infalling Group. The two infalling groups are identified in spectroscopic, X-ray, and weak-lensing maps. We identify active galactic nuclei (AGNs), star-forming galaxies, E+A galaxies, and quiescent galaxies based on the spectroscopy. The fractions of AGN and post-starburst E+A galaxies in A2029 are similar to those of other clusters. We derive the stellar mass (M_*_)-metallicity relation of A2029 based on 227 star-forming members; A2029 members within 10^9^M_{sun}_<M_*_<10^9.5^M_{sun}_ are more metal-rich than Sloan Digital Sky Survey galaxies within the same mass range. We utilize the spectroscopic index D_n_4000, a strong age indicator, to trace past and future evolution of the A2029 system. The median D_n_4000 of the members decreases as the projected clustercentric distance increases for all three subsystems. The D_n_4000-M_*_ relations of the members in A2029 and its two infalling groups differ significantly, indicating the importance of stochastic effects for understanding the evolution of cluster galaxy populations.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/705/68
- Title:
- A Spitzer ultradeep survey (SUUSS)
- Short Name:
- J/ApJ/705/68
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We carried out an unbiased, spectroscopic survey using the low-resolution module of the infrared spectrograph (IRS) onboard Spitzer targeting two 2.6 square arcminute regions in the GOODS-North field. The IRS was used in a spectral mapping mode with 5hr of effective integration time per pixel. One region was covered between 14 and 21um and the other between 20 and 35um. We extracted spectra for 45 sources. About 84% of the sources have reported detections by GOODS at 24um, with a median f_{nu}_(24um)~100uJy. All but one source are detected in all four IRAC bands, 3.6 to 8um. We use a new cross-correlation technique to measure redshifts and estimate IRS spectral types; this was successful for ~60% of the spectra. Fourteen sources show significant polycyclic aromatic hydrocarbon emission, four mostly SiO absorption, eight present mixed spectral signatures (low PAH and/or SiO) and two show a single line in emission. For the remaining 17, no spectral features were detected. Redshifts range from z~0.2 to z~2.2, with a median of 1. IR luminosities are roughly estimated from 24um flux densities, and have median values of 2.2x10^11^L_{sun}_ and 7.5x10^11^L_{sun}_ at z~1 and z~2, respectively. This sample has fewer active galactic nuclei than previous faint samples observed with the IRS, which we attribute to the fainter luminosities reached here.
- ID:
- ivo://CDS.VizieR/J/ApJ/884/100
- Title:
- Astrochemical study along M83 circumnuclear ring
- Short Name:
- J/ApJ/884/100
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report an astrochemical study on the evolution of interstellar molecular clouds and consequent star formation in the center of the barred spiral galaxy M83. We used the Atacama Large Millimeter/submillimeter Array (ALMA) to image molecular species indicative of shocks (SiO and CH_3_OH), dense cores (N_2_H^+^), and photodissociation regions (CN and CCH), as well as a radio recombination line (H41{alpha}) tracing active star-forming regions. M83 has a circumnuclear gas ring that is joined at two intersections by gas streams from the leading- edge gas lanes on the bar. We found elevated abundances of the shock and dense-core tracers in one of the orbit-intersecting areas, and found peaks of CN and H41{alpha} downstream. In the other orbit-intersection area, we found a similar enhancement of the shock tracers, but less variation of other tracers, and no sign of active star formation in the stream. We propose that the observed chemical variation or lack of it is due to the presence or absence of collision-induced evolution of molecular clouds and induced star formation. This work presents the clearest case of the chemical evolution in the circumnuclear rings of barred galaxies thanks to the ALMA resolution and sensitivity.
- ID:
- ivo://CDS.VizieR/J/A+A/590/A31
- Title:
- ASTRODEEP Frontier Fields Catalogues
- Short Name:
- J/A+A/590/A31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present multiwavelength photometric catalogues (HST, Spitzer and Hawk-I K band) for the first two of the Frontier Fields, Abell2744 and MACSJ0416 (plus their parallel fields). To detect faint sources even in the central regions of the clusters, we develop a robust and repeatable procedure that uses the public codes Galapagos and Galfit to model and remove most of the light contribution from both the brightest cluster members as well as the ICL. We perform the detection on the HST H160 processed image to obtain a pure H-selected sample. We also add a sample of sources which are undetected in the H160 image but appear on a stacked infrared image. Photometry in the other HST bands is obtained using SExtractor, performed again on residual images after the Galfit procedure for foreground light removal. Photometry on the Hawk-I and IRAC bands has been obtained using our PSF-matching deconfusion code T-PHOT. A similar procedure, but without the need for the foreground light removal, is adopted for the Parallel fields. The procedure allows for the detection and the photometric measurements of ~2500 sources per field. We deliver and release complete photometric H-detected catalogues, with the addition of a complementary sample of infrared-detected sources. All objects have multiwavelength coverage including B to H HST bands, plus K band from Hawk-I, and 3.6 - 4.5 {\mu}m from Spitzer. Full and detailed treatment of photometric errors is included. We perform basic sanity checks on the reliability of our results. The multiwavelength catalogues are publicly available and are ready to be used for scientific purposes. Our procedures allows for the detection of outshined objects near the bright galaxies, which, coupled with the magnification effect of the clusters, can reveal extremely faint high redshift sources. Full analysis on photometric redshifts is presented in a companion Paper II. We present the first public release of photometric redshifts, galaxy rest-frame properties and associated magnification values in the cluster and parallel pointings of the first two Frontier Fields, Abell-2744 and MACS-J0416. We exploit a multi-wavelength catalogue ranging from HST to ground-based K and Spitzer IRAC which is specifically designed to enable detection and measurement of accurate fluxes in crowded cluster regions. The multi-band information is used to derive photometric redshifts and physical properties of sources detected either in the H-band image alone or from a stack of four WFC3 bands. To minimize systematics median photometric redshifts are assembled from six different approaches to photo-z estimates. Their reliability is assessed through a comparison with available spectroscopic samples. State of the art lensing models are used to derive magnification values on an object-by-object basis by taking into account sources positions and redshifts. We show that photometric redshifts reach a remarkable ~3-5% accuracy. After accounting for magnification the H band number counts are found in agreement at bright magnitudes with number counts from the CANDELS fields, while extending the presently available samples to galaxies intrinsically as faint as H160~32-33 thanks to strong gravitational lensing. The Frontier Fields allow to probe the galaxy stellar mass distribution at 0.5-1.5dex lower masses, depending on magnification, with respect to extragalactic wide fields, including sources at Mstar~10^7-10^8^M_{sun}_ at z>5. Similarly, they allow the detection of objects with intrinsic SFRs>1dex lower than in the CANDELS fields reaching 0.1-1M_{sun}_/yr at z~6-10.
- ID:
- ivo://CDS.VizieR/J/A+A/649/A22
- Title:
- ASTRODEEP-GS43 catalogue
- Short Name:
- J/A+A/649/A22
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- We present ASTRODEEP-GS43, a new multiwavelength photometric catalogue of the GOODS-South field, which builds and improves upon the previously released CANDELS catalogue. We provide photometric fluxes and corresponding uncertainties in 43 optical and infrared bands (25 wide and 18 medium filters), as well as photometric redshifts and physical properties of the 34930 CANDELS H-detected objects, plus an additional sample of 178 H-dropout sources, of which 173 are Ks-detected and 5 IRAC-detected. We keep the CANDELS photometry in 7 bands (CTIOU, Hubble Space Telescope WFC3 and ISAAC-K), and measure from scratch the fluxes in the other 36 (VIMOS, HST ACS, HAWK-I Ks, Spitzer IRAC, and 23 from Subaru SuprimeCAM and Magellan-Baade Fourstar) with state-of-the-art techniques of template-fitting. We then compute new photometric redshifts with three different software tools, and take the median value as best estimate. We finally evaluate new physical parameters from SED fitting, comparing them to previously published ones. Comparing to a sample of 3931 high quality spectroscopic redshifts, for the new photo-z's we obtain a normalized median absolute deviation (NMAD) of 0.015 with 3.01% of outliers (0.011, 0.22% on the bright end at I_814_<22.5), similarly to the best available published samples of photometric redshifts, such as the COSMOS UltraVISTA catalogue. The ASTRODEEP-GS43 results are in qualitative agreement with previously published catalogues of the GOODS-South field, improving on them particularly in terms of SED sampling and photometric redshift estimates. The catalogue is available for download from the Astrodeep website.
- ID:
- ivo://CDS.VizieR/J/MNRAS/396/1231
- Title:
- Astrophotometric catalogue of NGC 891
- Short Name:
- J/MNRAS/396/1231
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep VI images obtained with the Advanced Camera for Surveys on board the Hubble Space Telescope, covering three fields in the north-east side of the edge-on disc galaxy NGC 891. The observed fields span a wide range of galactocentric distances along the eastern minor axis, extending from the plane of the disc to 12kpc, and out to ~25kpc along the major axis. The photometry of individual stars reaches ~2.5mag below the tip of the red giant branch. We use the astrophotometric catalogue to probe the stellar content and metallicity distribution across the thick disc and spheroid of NGC 891.
- ID:
- ivo://CDS.VizieR/J/ApJS/250/23
- Title:
- AstroSat/UVIT and Chandra X-ray sources in M31
- Short Name:
- J/ApJS/250/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An ultraviolet (UV) survey of M31 has been carried out during 2017-19 with the Ultra-Violet Imaging Telescope (UVIT) instrument on board the AstroSat Observatory. Here we match the M31 UVIT source catalog with the Chandra source catalog. We find 67 UVIT/Chandra sources detected in a varying number of UV and X-ray bands. The UV and X-ray photometry is analyzed using power-law and blackbody models. The X-ray types include 15 low-mass X-ray binaries (LMXBs) and five active galactic nuclei. Crossmatches with catalogs of stars, clusters, and other source types yield the following: 20 of the UVIT/Chandra sources match with M31 globular clusters, and nine with foreground stars. Three more globular clusters and two more foreground stars are consistent with the UVIT source positions although outside the Chandra match radius of 1". The UV emission of the UVIT/Chandra sources associated with globular clusters is consistent with emission from blue horizontal branch stars rather than from the X-ray source. The LMXBs in globular clusters are among the most luminous globular clusters in M31. Comparison with stellar evolutionary tracks shows that the UVIT/Chandra sources with high UV blackbody temperatures are consistent with massive (10-30M_{sun}_) stars in M31.
- ID:
- ivo://CDS.VizieR/J/AJ/83/1549
- Title:
- A study of field galaxies. I.
- Short Name:
- J/AJ/83/1549
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As a first step towards a redetermination of the luminosity function and space distribution of field galaxies, we present data on a magnitude limited sample of galaxies in eight fields in the north and south galactic polar caps. Redshifts, accurate to about 100 km/s have been obtained for 164 of 184 galaxies brighter than J=15.0 (B~15.5) We have also measured magnitudes and colors for a large sample of 807 galaxies, complete to J~15.7.
- ID:
- ivo://CDS.VizieR/J/A+AS/31/439
- Title:
- A Survey of HII Regions in M31
- Short Name:
- J/A+AS/31/439
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An H-alpha survey, using a focal reducer and narrow-band interference filters, has resulted in the detection of nearly a thousand HII regions in M31. The catalog gives their positions, dimensions, and surface brightnesses. The surface brightnesses are on an absolute scale; the photographic measures were calibrated by using photoelectric measures from two different sources. The detection limit reached corresponds to an emission measure of 40cm^-6^pc at a temperature of 10000K.
- ID:
- ivo://CDS.VizieR/J/A+A/281/15
- Title:
- Asymmetries in radio source structures
- Short Name:
- J/A+A/281/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)