- ID:
- ivo://CDS.VizieR/J/AJ/147/99
- Title:
- Spectroscopy of 73 stripped core-collapse supernovae
- Short Name:
- J/AJ/147/99
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 645 optical spectra of 73 supernovae (SNe) of Types IIb, Ib, Ic, and broad-lined Ic. All of these types are attributed to the core collapse of massive stars, with varying degrees of intact H and He envelopes before explosion. The SNe in our sample have a mean redshift ${<}cz${>} = 4200 km/s. Most of these spectra were gathered at the Harvard-Smithsonian Center for Astrophysics (CfA) between 2004 and 2009. For 53 SNe, these are the first published spectra. The data coverage ranges from mere identification (1-3 spectra) for a few SNe to extensive series of observations (10-30 spectra) that trace the spectral evolution for others, with an average of 9 spectra per SN. For 44 SNe of the 73 SNe presented here, we have well-determined dates of maximum light to determine the phase of each spectrum. Our sample constitutes the most extensive spectral library of stripped-envelope SNe to date. We provide very early coverage (as early as 30 days before V-band max) for photospheric spectra, as well as late-time nebular coverage when the innermost regions of the SN are visible (as late as 2 yr after explosion, while for SN 1993J, we have data as late as 11.6 yr). This data set has homogeneous observations and reductions that allow us to study the spectroscopic diversity of these classes of stripped SNe and to compare these to SNe-gamma-ray bursts. We undertake these matters in follow-up papers.
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- ID:
- ivo://CDS.VizieR/J/ApJ/834/210
- Title:
- Spectroscopy of strong lensing galaxy clusters
- Short Name:
- J/ApJ/834/210
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an extensive spectroscopic follow-up campaign of 29 strong lensing (SL) selected galaxy clusters discovered primarily in the Second Red-Sequence Cluster Survey (RCS-2). Our spectroscopic analysis yields redshifts for 52 gravitational arcs present in the core of our galaxy clusters, which correspond to 35 distinct background sources that are clearly distorted by the gravitational potential of these clusters. These lensed galaxies span a wide redshift range of 0.8<=z<=2.9, with a median redshift of z_s_=1.8+/-0.1. We also measure reliable redshifts for 1004 cluster members, allowing us to obtain robust velocity dispersion measurements for 23 of these clusters, which we then use to determine their dynamical masses by using a simulation-based {sigma}_DM_-M_200_ scaling relation. The redshift and mass ranges covered by our SL sample are 0.22<=z<=1.01 and 5x10^13^M_200_/h_70_^-1^M_{sun}_<=1.9x10^15^, respectively. We analyze and quantify some possible effects that might bias our mass estimates, such as the presence of substructure, the region where cluster members are selected for spectroscopic follow-up, the final number of confirmed members, and line-of-sight effects. We find that 10 clusters of our sample with N_mem_>~20 show signs of dynamical substructure. However, the velocity data of only one system is inconsistent with a uni-modal distribution. We therefore assume that the substructures are only marginal and not of comparable size to the clusters themselves. Consequently, our velocity dispersion and mass estimates can be used as priors for SL mass reconstruction studies and also represent an important step toward a better understanding of the properties of the SL galaxy cluster population.
- ID:
- ivo://CDS.VizieR/J/ApJ/850/94
- Title:
- Spectroscopy of the fields of gravitational lenses
- Short Name:
- J/ApJ/850/94
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Strong gravitational lensing provides an independent measurement of the Hubble parameter (H_0_). One remaining systematic is a bias from the additional mass due to a galaxy group at the lens redshift or along the sightline. We quantify this bias for more than 20 strong lenses that have well-sampled sightline mass distributions, focusing on the convergence {kappa} and shear {gamma}. In 23% of these fields, a lens group contributes >=1% convergence bias; in 57%, there is a similarly significant line-of-sight group. For the nine time-delay lens systems, H0 is overestimated by 11_-2_^+3^% on average when groups are ignored. In 67% of fields with total {kappa}>=0.01, line-of-sight groups contribute >~2x more convergence than do lens groups, indicating that the lens group is not the only important mass. Lens environment affects the ratio of four (quad) to two (double) image systems; all seven quads have lens groups while only 3 of 10 doubles do, and the highest convergences due to lens groups are in quads. We calibrate the {gamma}-{kappa} relation: log({kappa}_tot_)=(1.94+/-0.34)log({gamma}_tot_)+(1.31+/-0.49) with an rms scatter of 0.34dex. Although shear can be measured directly from lensed images, unlike convergence, it can be a poor predictor of convergence; for 19% of our fields, {kappa} is >~2{gamma}. Thus, accurate cosmology using strong gravitational lenses requires precise measurement and correction for all significant structures in each lens field.
- ID:
- ivo://CDS.VizieR/J/AJ/132/2596
- Title:
- Spectroscopy of Ultraluminous IR galaxies
- Short Name:
- J/AJ/132/2596
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the types of nuclear environments that produce OH megamasers (OHMs) with a study of the optical spectra of 40 OHM host galaxies and a control sample of 30 non-masing (ultra)luminous infrared galaxies ([U]LIRGs). The optical spectrophotometry provides spatially resolved spectra of multiple nuclei in a few of these merging systems. Of the 40 OHMs classified, 33% are starbursts, 42% are LINERs, and 25% are Seyfert 2 galaxies; the classification of the non-masing control sample is similar.
- ID:
- ivo://CDS.VizieR/J/ApJ/668/853
- Title:
- Spectroscopy of UltraStrong Emission Line galaxies
- Short Name:
- J/ApJ/668/853
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the results of a narrowband search for ultrastrong emission line galaxies (USELs) with EW(H{beta})>=30{AA}. A total of 542 candidate galaxies are found in a one-half square degree survey using two ~120{AA} filters centered at 8150 and 9140{AA} with Subaru SuprimeCam. Follow-up spectroscopy for randomly selected objects in the candidate sample with Keck II DEIMOS shows that they consist of [OIII] {lambda}5007-, [OII] {lambda}3727-, and H{alpha}-selected strong emission line galaxies at intermediate redshift (z<1) and Ly{alpha}-emitting galaxies at high redshift (z>>5).
- ID:
- ivo://CDS.VizieR/J/ApJ/693/1713
- Title:
- Spectroscopy of X-ray sources in ECDF-S
- Short Name:
- J/ApJ/693/1713
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results of our optical spectroscopy program aimed to provide redshifts and identifications for the X-ray sources in the Extended Chandra Deep Field South. A total of 339 sources were targeted using the IMACS spectrograph at the Magellan telescopes and the VIMOS spectrograph at the VLT. We measured redshifts for 186 X-ray sources, including archival data and a literature search. We find that the active galactic nucleus (AGN) host galaxies have on average redder rest-frame optical colors than nonactive galaxies, and that they live mostly in the "green valley". The dependence of the fraction of AGNs that are obscured on both luminosity and redshift is confirmed at high significance and the observed AGN spatial density is compared with the expectations from existing luminosity functions. These AGNs show a significant difference in the mid-IR to X-ray flux ratio for obscured and unobscured AGNs, which can be explained by the effects of dust self-absorption on the former. This difference is larger for lower luminosity sources, which is consistent with the dust opening angle depending on AGN luminosity.
- ID:
- ivo://CDS.VizieR/J/A+A/618/A85
- Title:
- Spectroscopy of 3<z<4 quiescent galaxies
- Short Name:
- J/A+A/618/A85
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Keck-MOSFIRE H and K spectra for a sample of 24 candidate quiescent galaxies at 3<z<4, identified from their rest-frame UVJ colors and photometric redshifts in the ZFOURGE and 3DHST surveys. With median integration times of one hour in H and five in K, we obtain spectroscopic redshifts for half of the sample, using either Balmer absorption lines or nebular emission lines. We confirm the high accuracy of the photometric redshifts for this spectroscopically-confirmed sample, with a median |Zphot-Zspec|/(1+Zspec) of 1.2%. Two galaxies turn out to be dusty H{alpha} emitters at lower redshifts (z<2.5), and these are the only two detected in the sub-mm with ALMA. High equivalent-width [OIII] emission is observed in two galaxies, contributing up to 30% of the K-band flux and mimicking the UVJ colors of an old stellar population. This implies a failure rate of only 20% for the UVJ selection at these redshifts. Lastly, Balmer absorption features are identified in four galaxies, among the brightest of the sample, confirming the absence of OB stars. We then modeled the spectra and photometry of all quiescent galaxies with a wide range of star-formation histories. We find specific star-formation rates (sSFR) lower than 0.15Gyr^-1^ (a factor of ten below the main sequence) for all but one galaxy, and lower than 0.01Gyr^-1^ for half of the sample. These values are consistent with the observed H{beta} and [OII] luminosities, and the ALMA non-detections. The implied formation histories reveal that these galaxies have quenched on average 300Myr prior to being observed, between z=3.5 and 5, and that half of their stars were formed by z~5.5 with a mean SFR~300M_{sun}_/yr. We finally compared the UVJ selection to a selection based instead on the sSFR, as measured from the photometry. We find that galaxies a factor of ten below the main sequence are 40% more numerous than UVJ-selected quiescent galaxies, implying that the UVJ selection is pure but incomplete. Current models fail at reproducing our observations, and underestimate either the number density of quiescent galaxies by more than an order of magnitude, or the duration of their quiescence by a factor two. Overall, these results confirm the existence of an unexpected population of quiescent galaxies at z>3, and offer the first insights on their formation histories.
- ID:
- ivo://CDS.VizieR/J/MNRAS/478/4952
- Title:
- SPIDERS BCGs gri photometry
- Short Name:
- J/MNRAS/478/4952
- Date:
- 10 Dec 2021 13:51:48
- Publisher:
- CDS
- Description:
- We present a sample of 329 low-to intermediate-redshift (0.05<z<0.3) brightest cluster galaxies (BCGs) in X-ray-selected clusters from the SPectroscopic IDentification of eRosita Sources survey, a spectroscopic survey within Sloan Digital Sky Survey-IV (SDSS-IV). We define our BCGs by simultaneous consideration of legacy X-ray data from ROSAT, maximum-likelihood outputs from an optical cluster-finder algorithm and visual inspection. Using SDSS imaging data, we fit Sersic profiles to our BCGs in three bands (g, r, i) with SIGMA a GALFIT-based software wrapper. We examine the reliability of our fits by running our pipeline on ~10^4^ point spread function-convolved model profiles injected into eight random cluster fields; we then use the results of this analysis to create a robust subsample of 198 BCGs. We outline three cluster properties of interest: overall cluster X-ray luminosity (L_X_), cluster richness as estimated by REDMAPPER ({lambda}),and cluster halo mass (M_200_), which is estimated via velocity dispersion. In general, there are significant correlations with BCG stellar mass between all three environmental properties, but no significant trends arise with either Sersic index or effective radius. There is no major environmental dependence on the strength of the relation between effective radius and BCG stellar mass. Stellar mass therefore arises as the most important factor governing BCG morphology. Our results indicate that our sample consists of a large number of relaxed, mature clusters containing broadly homogeneous BCGs up to z~0.3, suggesting that there is little evidence for much ongoing structural evolution for BCGs in these systems.
- ID:
- ivo://CDS.VizieR/J/ApJ/907/123
- Title:
- Spin Parity of Spiral Galaxies. III.
- Short Name:
- J/ApJ/907/123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is a revised catalog of spiral winding direction of SDSS spiral galaxies published by Shamir (2017PASA...34...11S). Whether the spiral pattern as projected on the sky is S-wise or Z-wise (Shamir called them counter clock wise and clockwise, respectively) can be an unambiguous tool to identify whether the galaxy spin vector is pointing toward or away from us as all the spirals are safely regarded as trailing spirals (Iye et al., 2019ApJ...886..113S). We used Shamir's catalog to analyze the dipole anisotropy in their large-scale structure and found that there exist rather massive duplicated entries and a few other minor errors in the original catalog. In this revised version those duplicated entries are cleaned keeping the judgment of the spiral winding direction due to Shamir (2017PASA...34...11S) except for a several obviously inconsistent cases. These corrections were necessary to make analysis of the large scale distribution of spin vectors of galaxies of the SDSS sample in our paper.
- ID:
- ivo://CDS.VizieR/J/ApJS/244/30
- Title:
- Spitzer catalog of Herschel star-forming galaxies
- Short Name:
- J/ApJS/244/30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The largest Herschel extragalactic surveys, H-ATLAS and HerMES, have selected a sample of "ultrared" dusty star-forming galaxies (DSFGs) with rising SPIRE flux densities (S_500_>S_350_>S_250_; the so-called "500{mu}m risers") as an efficient way for identifying DSFGs at higher redshift (z>4). In this paper, we present a large Spitzer follow-up program of 300 Herschel ultrared DSFGs. We have obtained high-resolution Atacama Large Millimeter/submillimeter Array, Northern Extended Millimeter Array, and SMA data for 63 of them, which allow us to securely identify the Spitzer/IRAC counterparts and classify them as gravitationally lensed or unlensed. Within the 63 ultrared sources with high-resolution data, ~65% appear to be unlensed and ~27% are resolved into multiple components. We focus on analyzing the unlensed sample by directly performing multiwavelength spectral energy distribution modeling to derive their physical properties and compare with the more numerous z~2 DSFG population. The ultrared sample has a median redshift of 3.3, stellar mass of 3.7x10^11^M_{sun}_, star formation rate (SFR) of 730M_{sun}_/yr, total dust luminosity of 9.0x10^12^L_{sun}_, dust mass of 2.8x10^9^M_{sun}_, and V-band extinction of 4.0, which are all higher than those of the ALESS DSFGs. Based on the space density, SFR density, and stellar mass density estimates, we conclude that our ultrared sample cannot account for the majority of the star-forming progenitors of the massive, quiescent galaxies found in infrared surveys. Our sample contains the rarer, intrinsically most dusty, luminous, and massive galaxies in the early universe that will help us understand the physical drivers of extreme star formation.