- ID:
- ivo://CDS.VizieR/J/ApJ/890/7
- Title:
- Environment of galaxies in the 5 CANDELS fields
- Short Name:
- J/ApJ/890/7
- Date:
- 17 Jan 2022 00:15:58
- Publisher:
- CDS
- Description:
- We present a robust method, weighted von Mises kernel density estimation, along with boundary correction to reconstruct the underlying number density field of galaxies. We apply this method to galaxies brighter than Hubble Space Telescope/F160w<=26 AB mag in the redshift range 0.4<=z<=5 in the five CANDELS fields (GOODS-N, GOODS-S, EGS, UDS, and COSMOS). We then use these measurements to explore the environmental dependence of the star formation activity of galaxies. We find strong evidence of environmental quenching for massive galaxies (M>~10^11^M_{sun}_) out to z~3.5 such that an overdense environment hosts >~20% more massive quiescent galaxies than an underdense region. We also find that environmental quenching efficiency grows with stellar mass and reaches ~60% for massive galaxies at z~0.5. The environmental quenching is also more efficient than stellar mass quenching for low-mass galaxies (M>~10^10^M_{sun}_) at low and intermediate redshifts (z<~1.2). Our findings concur thoroughly with the "overconsumption" quenching model where the termination of cool gas accretion (cosmological starvation) happens in an overdense environment and the galaxy starts to consume its remaining gas reservoir in depletion time. The depletion time depends on the stellar mass and could explain the evolution of environmental quenching efficiency with stellar mass.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/135/1311
- Title:
- Environments of moderate redshift radio galaxies
- Short Name:
- J/AJ/135/1311
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the local universe, high-power radio galaxies live in lower-density environments than low-luminosity radio galaxies. If this trend continued to higher redshifts, powerful radio galaxies would serve as efficient probes of moderate redshift groups and poor clusters. Photometric studies of radio galaxies at 0.3<~z<~0.5 suggest that the radio luminosity-environment correlation disappears at moderate redshifts, though this could be the result of foreground/background contamination affecting the photometric measures of environment. We have obtained multi-object spectroscopy in the fields of 14 lower luminosity (L_1.4GHz_<4x10^24^W/Hz) and higher luminosity (L_1.4GHz_>1.2x10^25^W/Hz) radio galaxies at z~0.3 to spectroscopically investigate the link between the environment and the radio luminosity of radio galaxies at moderate redshifts. Our results support the photometric analyses; there does not appear to be a correlation between the luminosity of a radio galaxy and its environment at moderate redshifts. Hence, radio galaxies are not efficient signposts for group environments at moderate redshifts.
- ID:
- ivo://CDS.VizieR/J/ApJ/613/129
- Title:
- Equivalent widths of QSOs
- Short Name:
- J/ApJ/613/129
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a search for variability in the equivalent widths (EWs) of narrow, associated (|{Delta}v|<=5000km/s) absorption lines found in the UV spectra of z<=1.5 quasars. The goal of this search was to use variability as a means of identifying absorption lines arising in gas that is intrinsic to the quasar central engine. We have compared archival Hubble Space Telescope (HST) Faint Object Spectrograph (FOS) spectra of quasars with recent spectra obtained as part of our own snapshot survey of the same objects with the Space Telescope Imaging Spectrograph (STIS). The intervals between observations are 4-10yr. We primarily focused on the C IV absorption lines, although we also studied other lines available in the same spectra (e.g., Ly{alpha}, N V, O VI).
- ID:
- ivo://CDS.VizieR/J/A+A/421/59
- Title:
- Equivalent widths of VMF73 and VMF74 galaxies
- Short Name:
- J/A+A/421/59
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a spectroscopic analysis of two galaxy clusters out to ~4Mpc at z~0.2. The two clusters VMF73 and VMF74 identified by Vikhlinin et al. (1998, Cat. <J/ApJ/502/558>) were observed with MOSCA at the Calar Alto 3.5m telescope. Both clusters lie in the ROSAT PSPC field R285 and were selected from the X-ray Dark Cluster Survey (Gilbank et al., 2004MNRAS.348..551G) that provides optical V- and I-band data. VMF73 and VMF74 are located at respective redshifts of z=0.25 and z=0.18 with velocity dispersions of 671km/s and 442km/s, respectively. The spectroscopic observations reach out to ~2.5 virial radii. Line strength measurements of the emission lines H_alpha and [OII]3727 are used to assess the star formation activity of cluster galaxies which show radial and density dependences. The mean and median of both line strength distributions as well as the fraction of star forming galaxies increase with increasing clustercentric distance and decreasing local galaxy density. Except for two galaxies with strong H_alpha and [OII] emission, all of the cluster galaxies are normal star forming or passive galaxies. Our results are consistent with other studies that show the truncation in star formation occurs far from the cluster centre.
- ID:
- ivo://CDS.VizieR/J/A+A/482/419
- Title:
- ESO Distant Cluster Survey, EDisCS. II
- Short Name:
- J/A+A/482/419
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present spectroscopic observations of galaxies in 15 survey fields as part of the ESO Distant Cluster Survey (EDisCS). We determine the redshifts and velocity dispersions of the galaxy clusters located in these fields, and we test for possible substructure in the clusters. We obtained multi-object mask spectroscopy using the FORS2 instrument at the VLT. We reduced the data with particular attention to the sky subtraction. We implemented the method of Kelson for performing sky subtraction prior to any rebinning/interpolation of the data. From the measured galaxy redshifts, we determine cluster velocity dispersions using the biweight estimator and test for possible substructure in the clusters using the Dressler-Shectman test. The method of subtracting the sky prior to any rebinning/interpolation of the data delivers photon-noise-limited results, whereas the traditional method of subtracting the sky after the data have been rebinned/interpolated results in substantially larger noise for spectra from tilted slits. Redshifts for individual galaxies are presented and redshifts and velocity dispersions are presented for 21 galaxy clusters. For the 9 clusters with at least 20 spectroscopically confirmed members, we present the statistical significance of the presence of substructure obtained from the Dressler-Shectman test, and substructure is detected in two of the clusters. Together with data from our previous paper, spectroscopy and spectroscopic velocity dispersions are now available for 26 EDisCS clusters with redshifts in the range 0.40-0.96 and velocity dispersions in the range 166-1080km/s.
- ID:
- ivo://CDS.VizieR/J/A+A/384/81
- Title:
- ESO Imaging Survey. CDF-S point sources
- Short Name:
- J/A+A/384/81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper describes the methodology currently being implemented in the EIS pipeline for analysing optical/infrared multi-colour data. The aim is to identify different classes of objects as well as possible undesirable features associated with the construction of colour catalogues. The tools developed are used for a preliminary analysis of the multi-colour point source catalogue constructed from the optical/infrared imaging data obtained for the Chandra Deep Field South (CDF-S). These data are publicly available, representing the first installment of the ongoing EIS Deep Public Survey.
- ID:
- ivo://CDS.VizieR/J/A+A/556/A141
- Title:
- ESO-UVES Advanced Data Products (EUADP) sample
- Short Name:
- J/A+A/556/A141
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present here a dataset of quasars observed with the Ultraviolet Visual Echelle Spectrograph (UVES) on the Very Large Telescope and available in the European Southern Observatory UVES Advanced Data Products (EUADP) archive. The sample is made up of a total of 250 high resolution quasar spectra with emission redshifts ranging from 0.191<=zem<=6.311. The total UVES exposure time of this dataset is 1560 h. Thanks to the high resolution of UVES spectra, it is possible to unambiguously measure the column density of absorbers with damping wings, down to N_HI_>~10^19^cm^-2^, which constitutes the sub-damped Ly{alpha} absorber (sub-DLA) threshold. Within the wavelength coverage of our UVES data, we find 150 damped Ly{alpha} systems (DLAs)/sub-DLAs in the range 1.5<zabs<4.7. Damped absorbers, seen in the spectra of background quasars, are unique probes to select HI-rich galaxies. These galaxies allow one to estimate the neutral gas mass over cosmological scales. The neutral gas mass is a possible indicator of gas consumption as star formation proceeds. The damped Ly{alpha} absorbers (DLAs; N_HI_>=2x10^20^cm^-2^) and sub-DLAs (10^19^<=N_HI_<=2x10^20^cm^-2^) are believed to contain a large fraction of neutral gas mass in the Universe. In aper I of the series, we presented the results of a search for DLAs and sub-DLAs in the European Southern Observatory (ESO) Ultraviolet Visual Echelle Spectrograph (UVES) advanced data products dataset of 250 quasars. Here we use an unbiased subsample of sub-DLAs from this dataset to derive their statistical properties. We built a subset of 122 quasars ranging from 1.5<z_em_<5.0, suitable for statistical analysis. The statistical sample was analyzed in conjunction with other sub-DLA samples from the literature. This resulted in a combined sample of 89 sub-DLAs over a redshift path of {Delta}z=193.
- ID:
- ivo://CDS.VizieR/J/A+A/507/85
- Title:
- ESO/VLT 3rd year type Ia supernova data set
- Short Name:
- J/A+A/507/85
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 139 spectra of 124 Type Ia supernovae (SNe Ia) that were observed at the ESO/VLT during the first three years of the Canada-France-Hawai Telescope (CFHT) supernova legacy survey (SNLS). This homogeneous data set is used to test for redshift evolution of SN Ia spectra, and will be used in the SNLS 3rd year cosmological analyses. Spectra have been reduced and extracted with a dedicated pipeline that uses photometric information from deep CFHT legacy survey (CFHT-LS) reference images to trace, at sub-pixel accuracy, the position of the supernova on the spectrogram as a function of wavelength. It also separates the supernova and its host light in ~60% of cases. The identification of the supernova candidates is performed using a spectrophotometric SN Ia model.
- ID:
- ivo://CDS.VizieR/J/AJ/137/3731
- Title:
- ESSENCE high-redshift supernova
- Short Name:
- J/AJ/137/3731
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of spectroscopic observations from the ESSENCE high-redshift supernova (SN) survey during its first four years of operation. This sample includes spectra of all SNe Ia whose light curves were presented by Miknaitis et al. (2007, Cat. J/ApJ/666/674) and used in the cosmological analyses of Davis et al. (2007ApJ...666..716D) and Wood-Vasey et al. (2007ApJ...666..694W). The sample represents 273hr of spectroscopic observations with 6.5-10m class telescopes of objects detected and selected for spectroscopy by the ESSENCE team. We present 184 spectra of 156 objects. Combining this sample with that of Matheson et al. (2008, Cat. J/AJ/135/1598), we have a total sample of 329 spectra of 274 objects. From this, we are able to spectroscopically classify 118 Type Ia SNe.
- ID:
- ivo://CDS.VizieR/J/ApJS/224/3
- Title:
- ESSENCE 6yr spectroscopic follow-up
- Short Name:
- J/ApJS/224/3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Equation of State: Supernovae trace Cosmic Expansion (ESSENCE) survey discovered 213 Type Ia supernovae at redshifts 0.1<z<0.81 between 2002 and 2008. We present their R- and I-band photometry, measured from images obtained using the MOSAIC II camera at the CTIO Blanco, along with rapid-response spectroscopy for each object. We use our spectroscopic follow-up observations to determine an accurate, quantitative classification, and precise redshift. Through an extensive calibration program we have improved the precision of the CTIO Blanco natural photometric system. We use several empirical metrics to measure our internal photometric consistency and our absolute calibration of the survey. We assess the effect of various potential sources of systematic bias on our measured fluxes, and estimate the dominant term in the systematic error budget from the photometric calibration on our absolute fluxes is ~1%.
