- ID:
- ivo://CDS.VizieR/J/ApJ/811/117
- Title:
- R-band PTF observations of SNe IIb
- Short Name:
- J/ApJ/811/117
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The progenitor stars of several Type IIb supernovae (SNe) show indications of extended hydrogen envelopes. These envelopes might be the outcome of luminous energetic pre-explosion events, so-called precursor eruptions. We use the Palomar Transient Factory (PTF) pre-explosion observations of a sample of 27 nearby SNe IIb to look for such precursors during the final years prior to the SN explosion. No precursors are found when combining the observations in 15-day bins, and we calculate the absolute-magnitude-dependent upper limit on the precursor rate. At the 90% confidence level, SNe IIb have on average <0.86 precursors as bright as an absolute R-band magnitude of -14 in the final 3.5 years before the explosion and <0.56 events over the final year. In contrast, precursors among SNe IIn have a >~5 times higher rate. The kinetic energy required to unbind a low-mass stellar envelope is comparable to the radiated energy of a few-weeks-long precursor that would be detectable for the closest SNe in our sample. Therefore, mass ejections, if they are common in such SNe, are radiatively inefficient or have durations longer than months. Indeed, when using 60-day bins, a faint precursor candidate is detected prior to SN 2012cs (~2% false-alarm probability). We also report the detection of the progenitor of SN 2011dh that does not show detectable variability over the final two years before the explosion. The suggested progenitor of SN 2012P is still present, and hence is likely a compact star cluster or an unrelated object.
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- ID:
- ivo://CDS.VizieR/J/ApJS/238/32
- Title:
- 3rd MAXI/GSC X-ray cat at high Galactic latitude
- Short Name:
- J/ApJS/238/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the third MAXI/GSC catalog in the high Galactic latitude sky (|b|>10{deg}) based on the 7-year data from 2009 August 13 to 2016 July 31, complementary to that in the low Galactic latitude sky (|b|<10{deg}) (Hori+ 2018ApJS..235....7H). We compile 682 sources detected at significances of s_D,4-10keV_>=6.5 in the 4-10keV band. A two-dimensional image fit based on the Poisson likelihood algorithm (C-statistics) is adopted for the detections and constraints on their fluxes and positions. The 4-10keV sensitivity reaches ~0.48mCrab, or ~5.9x10^-12^erg/cm^2^/s, over half of the survey area. Compared with the 37-month Hiroi+ (2013, J/ApJS/207/36) catalog, which adopted a threshold of s_D,4-10keV_>=7, the source number increases by a factor of ~1.4. The fluxes in the 3-4keV and 10-20keV bands are further estimated, and hardness ratios (HRs) are calculated using the 3-4keV, 4-10keV, 3-10keV, and 10-20keV band fluxes. We also make the 4-10keV light curves in 1-year bins for all the sources and characterize their variabilities with an index based on a likelihood function and the excess variance. Possible counterparts are found from five major X-ray survey catalogs by Swift, Uhuru, RXTE, XMM-Newton, and ROSAT, as well as an X-ray galaxy cluster catalog (MCXC). Our catalog provides the fluxes, positions, detection significances, HRs, 1-year bin light curves, variability indices, and counterpart candidates.
- ID:
- ivo://CDS.VizieR/J/ApJS/224/1
- Title:
- redMaPPer cluster catalog from DES data
- Short Name:
- J/ApJS/224/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe updates to the redMaPPer algorithm, a photometric red-sequence cluster finder specifically designed for large photometric surveys. The updated algorithm is applied to 150deg^2^ of Science Verification (SV) data from the Dark Energy Survey (DES), and to the Sloan Digital Sky Survey (SDSS) DR8 photometric data set. The DES SV catalog is locally volume limited and contains 786 clusters with richness {lambda}>20 (roughly equivalent to M_500c_>~10^14^h_70_^-1^M_{sun}_) and 0.2<z<0.9. The DR8 catalog consists of 26311 clusters with 0.08<z<0.6, with a sharply increasing richness threshold as a function of redshift for z>~0.35. The photometric redshift performance of both catalogs is shown to be excellent, with photometric redshift uncertainties controlled at the {sigma}_z_/(1+z)~0.01 level for z<~0.7 , rising to ~0.02 at z~0.9 in DES SV. We make use of Chandra and XMM X-ray and South Pole Telescope Sunyaev-Zeldovich data to show that the centering performance and mass-richness scatter are consistent with expectations based on prior runs of redMaPPer on SDSS data. We also show how the redMaPPer photo-z and richness estimates are relatively insensitive to imperfect star/galaxy separation and small-scale star masks.
- ID:
- ivo://CDS.VizieR/J/ApJ/785/104
- Title:
- redMaPPer. I. Algorithm applied to SDSS DR8
- Short Name:
- J/ApJ/785/104
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe redMaPPer, a new red sequence cluster finder specifically designed to make optimal use of ongoing and near-future large photometric surveys. The algorithm has multiple attractive features: (1) it can iteratively self-train the red sequence model based on a minimal spectroscopic training sample, an important feature for high-redshift surveys. (2) It can handle complex masks with varying depth. (3) It produces cluster-appropriate random points to enable large-scale structure studies. (4) All clusters are assigned a full redshift probability distribution P(z). (5) Similarly, clusters can have multiple candidate central galaxies, each with corresponding centering probabilities. (6) The algorithm is parallel and numerically efficient: it can run a Dark Energy Survey-like catalog in ~500 CPU hours. (7) The algorithm exhibits excellent photometric redshift performance, the richness estimates are tightly correlated with external mass proxies, and the completeness and purity of the corresponding catalogs are superb. We apply the redMaPPer algorithm to ~10000deg^2^ of SDSS DR8 data and present the resulting catalog of ~25000 clusters over the redshift range z{isin}[0.08,0.55]. The redMaPPer photometric redshifts are nearly Gaussian, with a scatter {sigma}_z_~0.006 at z~0.1, increasing to {sigma}_z_~0.02 at z~0.5 due to increased photometric noise near the survey limit. The median value for |{Delta}z|/(1+z) for the full sample is 0.006. The incidence of projection effects is low (<= 5%). Detailed performance comparisons of the redMaPPer DR8 cluster catalog to X-ray and Sunyaev-Zel'dovich catalogs are presented in a companion paper.
- ID:
- ivo://CDS.VizieR/J/ApJS/157/1
- Title:
- Red-Sequence Cluster Survey
- Short Name:
- J/ApJS/157/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Red-Sequence Cluster Survey (RCS) is a ~100{deg}^2^, two-filter imaging survey in the R_C_ and z' filters, designed primarily to locate and characterize galaxy clusters to redshifts as high as z=1.4. This paper provides a detailed description of the survey strategy and execution, including a thorough discussion of the photometric and astrometric calibration of the survey data. These catalogs, representing about 10% of the total survey and comprising a total of 429 candidate clusters and groups, contain a total of 67 cluster candidates at a photometric redshift of 0.9<z<1.4, down to the chosen significance threshold of 3.29{sigma}.
- ID:
- ivo://CDS.VizieR/J/A+A/490/945
- Title:
- Redshifs of galaxies in 23 EIS fields
- Short Name:
- J/A+A/490/945
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have carried out a spectroscopic survey of low-redshift galaxy systems identified by the matched-filter technique in a moderately deep I-band survey. We present new redshifts for 747 galaxies in 23 ESO Imaging Survey (EIS) cluster fields. We use the "gap"-technique to search for significant overdensities in redshift space for identifying groups/clusters of galaxies corresponding to the original EIS matched-filter cluster candidates. In this way we spectroscopically confirm systems in 10 of the 23 cluster candidate fields with a matched-filter estimated redshift z_MF_=0.3-0.4 and with spectroscopic redshifts in the range from z=0.158 to z=0.534, with the observations favouring the confirmation of systems at the lower redshift end. After careful analysis of the redshift distribution, one system was split into two very close clumps in redshift space. We find that the systems identified in the present paper span a broad range of velocity dispersion and richness. The measured one-dimensional velocity dispersion range from 175km/s to 497km/s, consistent with the values obtained in previous papers using much larger samples for systems over the same redshift range. Both undersampling and contamination by substructures contribute to the uncertainty of these measurements. The richness range corresponds to clusters with an estimated total luminosity in the range 12L^*^-65L^*^, but these estimates are very uncertain as are their relation to the velocity dispersion (mass) of the systems. From the analysis of the colours of the galaxy populations we find that ~60% of the spectroscopically confirmed systems have a "significant" red sequence. We find that the colour of the red sequence galaxies matches passive stellar evolution predictions. With this paper we complete our spectroscopic survey of the fields of 58 EIS cluster candidates with estimated redshifts z<=0.4 (see also Hansen et al., 2002, Cat. <J/A+A/388/1>; Olsen et al., 2003, Cat. <J/A+A/409/439>, Olsen et al., 2005, Cat. <J/A+A/435/781>). We have measured a total of 1954 galaxy redshifts in the range z=0.0065 to z=0.6706. Of the 58 systems we confirm 42 (~75%) with redshifts between z=0.095 and z=0.534.
- ID:
- ivo://CDS.VizieR/J/ApJ/731/103
- Title:
- Redshift catalog for Swift long GRBs
- Short Name:
- J/ApJ/731/103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of the redshifts for most long-duration gamma-ray bursts (GRBs) by Swift from 2004 December 20 to 2008 July 23 (258 bursts in total). All available information is collected, including spectroscopic redshifts, photometric redshift limits, and redshifts calculated from various luminosity relations. Error bars for the redshifts derived from the luminosity relations are asymmetric, with tails extended to the high-redshift end, and this effect is evaluated by looking at the 30% of Swift bursts with spectroscopic redshifts. A simulation is performed to eliminate this asymmetric effect, and the resultant redshift distribution is deconvolved. We test and confirm this simulation on the sample of bursts with known spectroscopic redshifts and then apply it to the 70% of Swift bursts that do not have spectroscopic measures. A final intrinsic redshift distribution is then made for almost all Swift bursts, and the efficiency of the spectroscopic detections is evaluated. The efficiency of spectroscopic redshifts varies from near unity at low redshift to 0.5 at z=1, to near 0.3 at z=4, and to 0.1 at z=6. We also find that the fraction of GRBs with z>5 is ~10%, and this fraction is compared with simulations from a cosmological model.
- ID:
- ivo://CDS.VizieR/J/AJ/149/178
- Title:
- Redshift catalog of galaxies in GOODS-South field
- Short Name:
- J/AJ/149/178
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We combine Hubble Space Telescope (HST)/Wide Field Camera3 (WFC3) imaging and G141 grism observations from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) and 3D-HST surveys to produce a catalog of grism spectroscopic redshifts for galaxies in the CANDELS/GOODS-South field. The WFC3/G141 grism spectra cover a wavelength range of 1.1{<=}{lambda}{<=}1.7{mu}m with a resolving power of R~130 for point sources, thus providing rest-frame optical spectra for galaxies out to z~3.5. The catalog is selected in the H-band (F160W) and includes both galaxies with and without previously published spectroscopic redshifts. Grism spectra are extracted for all H-band detected galaxies with H<=24 and a CANDELS photometric redshift z_phot_>=0.6. The resulting spectra are visually inspected to identify emission lines, and redshifts are determined using cross-correlation with empirical spectral templates. To establish the accuracy of our redshifts, we compare our results against high-quality spectroscopic redshifts from the literature. Using a sample of 411 control galaxies, this analysis yields a precision of {sigma}_NMAD_=0.0028 for the grism-derived redshifts, which is consistent with the accuracy reported by the 3D-HST team. Our final catalog covers an area of 153arcmin^2^ and contains 1019 redshifts for galaxies in GOODS-S. Roughly 60% (608/1019) of these redshifts are for galaxies with no previously published spectroscopic redshift. These new redshifts span a range of 0.677{<=}z{<=}3.456 and have a median redshift of z=1.282. The catalog contains a total of 234 new redshifts for galaxies at z>1.5. In addition, we present 20 galaxy pair candidates identified for the first time using the grism redshifts in our catalog, including four new galaxy pairs at z~2, nearly doubling the number of such pairs previously identified.
- ID:
- ivo://CDS.VizieR/J/A+A/465/1099
- Title:
- Redshift catalog of 691 objects in CDFS
- Short Name:
- J/A+A/465/1099
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper prepares a series of papers analysing the Intermediate MAss Galaxy Evolution Sequence (IMAGES) up to a redshift of one. Intermediate mass galaxies (M_J<=-20.3) are selected from the Chandra Deep Field South (CDFS) for which we identify a serious lack of spectroscopically determined redshifts. Our primary aim in this study is therefore to obtain a sample of intermediate-mass galaxies with known spectroscopic redshift to be used for further analysis of their 3D-kinematics. We also intend to test whether this important cosmological field may be significantly affected by cosmic variance. The spectroscopic observations were carried out using VIMOS on the ESO VLT. The data reduction was done using a set of semi-automatic IRAF procedures developed by our team. We have spectroscopically identified 691 objects including 580 galaxies, 7 QSOs, and 104 stars.
- ID:
- ivo://CDS.VizieR/J/A+A/635/A98
- Title:
- Redshift catalogs of the Abell 2163 core
- Short Name:
- J/A+A/635/A98
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Abell 2163 at z~=0.201 is one of the most massive galaxy clusters known, very likely in a post-merging phase. Data from several observational windows suggest a complex mass structure with interacting subsystems, which makes the reconstruction of a realistic merging scenario very difficult. A missing key element in this sense is unveiling the cluster mass distribution at high resolution. We perform such a reconstruction of the cluster inner total mass through a strong lensing model based on new spectroscopic redshift measurements. We use data from the Multi Unit Spectroscopic Explorer on the Very Large Telescope to confirm 12 multiple images of four sources with redshift values from 1.16 to 2.72. We also discover four new multiple images and identify 29 cluster members and 35 foreground and background sources. The resulting galaxy member and image catalogs are used to build five cluster total mass models. The fiducial model consists of 111 small-scale subhalos, plus a diffuse component, which is centered ~2" away from the BCG belonging to the east Abell 2163 subcluster. We confirm that the latter is well represented by a single, large-scale mass component. Its strong elongation towards a second (west) subcluster confirms the existence of a preferential axis, corresponding to the merging direction. From the fiducial model, we extrapolate the cumulative projected total mass profile and measure a value of M(<300kpc)=1.43_-0.06_^+0.07^x10^14^M_{sun}_, which has a significantly reduced statistical error compared with previous estimates, thanks to the inclusion of the spectroscopic redshifts. Our strong lensing results are very accurate: the model-predicted positions of the multiple images are, on average, only 0.15" away from the observed ones.
