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2651. Spectroscopy of 73 stripped core-collapse supernovae
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.
2652. Spectroscopy of strong lensing galaxy clusters
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.
2653. Spectroscopy of the B[e] star VES 695
ID:
ivo://CDS.VizieR/J/ApJ/700/209
Title:
Spectroscopy of the B[e] star VES 695
Short Name:
J/ApJ/700/209
Date:
21 Oct 2021
Publisher:
CDS
Description:
FS CMa type stars are a group of Galactic objects with the B[e] phenomenon. They exhibit strong emission-line spectra and infrared excesses, which are most likely due to recently formed circumstellar dust. The group content and identification criteria were described in the first two papers of the series. In this paper we report our spectroscopic and photometric observations of the optical counterpart of IRAS 00470+6429 obtained in 2003-2008. The optical spectrum is dominated by emission lines, most of which have P Cyg type profiles. We detected significant brightness variations, which may include a regular component, and variable spectral line profiles in both shape and position. The presence of a weak LiI6708{AA} line in the spectrum suggests that the object is most likely a binary system with a B2-B3 spectral-type primary companion of a luminosity logL/L_{sun}_=3.9+/-0.3 and a late-type secondary companion. We estimate a distance toward the object to be 2.0+/-0.3kpc from the Sun.
2654. Spectroscopy of the fields of gravitational lenses
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.
2655. Spectroscopy of the foreground population in Orion A
ID:
ivo://CDS.VizieR/J/AJ/153/188
Title:
Spectroscopy of the foreground population in Orion A
Short Name:
J/AJ/153/188
Date:
21 Oct 2021
Publisher:
CDS
Description:
We perform a spectroscopic survey of the foreground population in Orion A with MMT/Hectospec. We use these data, along with archival spectroscopic data and photometric data, to derive spectral types, extinction values, and masses for 691 stars. Using the Spitzer Space Telescope data, we characterize the disk properties of these sources. We identify 37 new transition disk (TD) objects, 1 globally depleted disk candidate, and 7 probable young debris disks. We discover an object with a mass of less than 0.018-0.030 M_{sun}_, which harbors a flaring disk. Using the H{alpha} emission line, we characterize the accretion activity of the sources with disks, and confirm that the fraction of accreting TDs is lower than that of optically thick disks (46%+/-7% versus 73%+/-9%, respectively). Using kinematic data from the Sloan Digital Sky Survey and APOGEE INfrared Spectroscopy of the Young Nebulous Clusters program (IN-SYNC), we confirm that the foreground population shows similar kinematics to their local molecular clouds and other young stars in the same regions. Using the isochronal ages, we find that the foreground population has a median age of around 1-2 Myr, which is similar to that of other young stars in Orion A. Therefore, our results argue against the presence of a large and old foreground cluster in front of Orion A.
2656. Spectroscopy of the Galactic bar. I.
ID:
ivo://CDS.VizieR/J/ApJ/691/1387
Title:
Spectroscopy of the Galactic bar. I.
Short Name:
J/ApJ/691/1387
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use Fabry-Perot absorption line imaging spectroscopy to measure radial velocities using the CaII line in 3360 stars toward three lines of sight in the Milky Way's bar: Baade's Window and offset position at (l,b)~(+/-5.0,-3.5{deg}). This sample includes 2488 bar red clump giants, 339 bar M/K-giants, and 318 disk main-sequence stars. We measure the first four moments of the stellar velocity distribution of the red clump giants, and find it to be symmetric and flat-topped. We also measure the line-of-sight average velocity and dispersion of the red clump giants as a function of distance in the bar.
2657. Spectroscopy of the LV2 proplyd in Orion
ID:
ivo://CDS.VizieR/J/AJ/130/1707
Title:
Spectroscopy of the LV2 proplyd in Orion
Short Name:
J/AJ/130/1707
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present high spatial resolution spectroscopic observations of the proplyd 167-317 (LV2) near the Trapezium cluster in the Orion Nebula, obtained during the system verification run of the Gemini Multi-Object Spectrograph (GMOS) Integral Field Unit (IFU) at the Gemini South Observatory. We have detected 38 forbidden and permitted emission lines associated with the proplyd and its redshifted jet.
2658. Spectroscopy of {theta}1 Ori C system
ID:
ivo://CDS.VizieR/J/other/Ap/54.81
Title:
Spectroscopy of {theta}1 Ori C system
Short Name:
J/other/Ap/54.81
Date:
21 Oct 2021
Publisher:
CDS
Description:
The spectral-double system escaping from multiple system theta1 Ori C is investigated. Radial velocities of both components are measured, for them are constructed and solved curves of radial velocity. Physical parameters of stars and their chemical composition are determined.
2659. Spectroscopy of TTau and Herbig Ae/Be candidates
ID:
ivo://CDS.VizieR/J/ApJ/657/884
Title:
Spectroscopy of TTau and Herbig Ae/Be candidates
Short Name:
J/ApJ/657/884
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present our diagnosis of the role that massive stars play in the formation of low- and intermediate-mass stars in OB associations (the lambda Ori region, Ori OB1, and Lac OB1 associations).
2660. Spectroscopy of Tuc-Hor candidate members
ID:
ivo://CDS.VizieR/J/AJ/147/146
Title:
Spectroscopy of Tuc-Hor candidate members
Short Name:
J/AJ/147/146
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the selection and spectroscopic confirmation of 129 new late-type (SpT=K3-M6) members of the Tucana-Horologium moving group, a nearby (d~40pc), young ({tau}~40Myr) population of comoving stars. We also report observations for 13 of the 17 known Tuc-Hor members in this spectral type range, and that 62 additional candidates are likely to be unassociated field stars; the confirmation frequency for new candidates is therefore 129/191=67%. We have used radial velocities, H{alpha} emission, and Li_6708_ absorption to distinguish between contaminants and bona fide members. Our expanded census of Tuc-Hor increases the known population by a factor of ~3 in total and by a factor of ~8 for members with SpT>=K3, but even so, the K-M dwarf population of Tuc-Hor is still markedly incomplete. Our expanded census allows for a much more detailed study of Tuc-Hor than was previously feasible. The spatial distribution of members appears to trace a two-dimensional sheet, with a broad distribution in X and Y, but a very narrow distribution (+/-5pc) in Z. The corresponding velocity distribution is very small, with a scatter of +/-1.1km/s about the mean UVW velocity for stars spanning the entire 50pc extent of Tuc-Hor. We also show that the isochronal age ({tau}~20-30Myr) and the lithium depletion boundary age ({tau}~40Myr) disagree, following the trend in other pre-main-sequence populations for isochrones to yield systematically younger ages. The H{alpha} emission line strength follows a trend of increasing equivalent width with later spectral type, as is seen for young clusters. We find that moving group members have been depleted of measurable lithium for spectral types of K7.0-M4.5. None of our targets have significant infrared excesses in the WISE W3 band, yielding an upper limit on warm debris disks of F<0.7%. Finally, our purely kinematic and color-magnitude selection procedure allows us to test the efficiency and completeness for activity-based selection of young stars. We find that 60% of K-M dwarfs in Tuc-Hor do not have ROSAT counterparts and would have been omitted in X-ray-selected samples. In contrast, GALEX UV-selected samples using a previously suggested criterion for youth achieve completeness of 77% and purity of 78%, and we suggest new SpT-dependent selection criteria that will yield >95% completeness for {tau}~40Myr populations with GALEX data available.

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