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3641. Subaru HSC counterpart candidates of GW170817
ID:
ivo://CDS.VizieR/J/PASJ/70/28
Title:
Subaru HSC counterpart candidates of GW170817
Short Name:
J/PASJ/70/28
Date:
21 Oct 2021
Publisher:
CDS
Description:
We perform a z-band survey for an optical counterpart of the binary neutron star coalescence GW170817 with Subaru/Hyper Suprime-Cam. Our untargeted transient search covers 23.6deg^2^ corresponding to the 56.6% credible region of GW170817 and reaches the 50% completeness magnitude of 20.6mag on average. As a result, we find 60 candidate extragalactic transients, including J-GEM17btc (also known as SSS17a/DLT17ck). While J-GEM17btc is associated with NGC 4993, which is firmly located inside the 3D skymap of GW170817, the other 59 candidates do not have distance information in the GLADE v2 catalog or NASA/IPAC Extragalactic Database. Among 59 of the candidates, 58 are located at the center of extended objects in the Pan-STARRS1 catalog, while one candidate has an offset. We present location, z-band apparent magnitude, and time variability of the candidates and evaluate the probabilities that they are located within the 3D skymap of GW170817. The probability for J-GEM17btc is 64%, which is much higher than for the other 59 candidates (9.3x10^-3^-2.1x10^-1^%). Furthermore, the possibility that at least one of the other 59 candidates is located within the 3D skymap is only 3.2%. Therefore, we conclude that J-GEM17btc is the most likely and distinguished candidate to be the optical counterpart of GW170817.
3642. Subaru new Ca filter transmission function
ID:
ivo://CDS.VizieR/J/ApJ/778/L13
Title:
Subaru new Ca filter transmission function
Short Name:
J/ApJ/778/L13
Date:
21 Oct 2021
Publisher:
CDS
Description:
Recent spectroscopic observations of the outer halo globular cluster (GC) NGC 2419 show that it is unique among GCs, in terms of chemical abundance patterns, and some suggest that it was originated in the nucleus of a dwarf galaxy. Here we show, from the Subaru narrowband photometry employing a calcium filter, that the red giant branch (RGB) of this GC is split into two distinct subpopulations. Comparison with spectroscopy has confirmed that the redder RGB stars in the hk[=(Ca-b)-(b-y)] index are enhanced in [Ca/H] by ~0.2dex compared to the bluer RGB stars. Our population model further indicates that the calcium-rich second generation stars are also enhanced in helium abundance by a large amount ({Delta}Y=0.19). Our photometry, together with the results for other massive GCs (e.g., {omega} Cen, M22, and NGC 1851), suggests that the discrete distribution of RGB stars in the hk index might be a universal characteristic of this growing group of peculiar GCs. The planned narrowband calcium photometry for the Local Group dwarf galaxies would help to establish an empirical connection between these GCs and the primordial building blocks in the hierarchical merging paradigm of galaxy formation.
3643. Subaru NIR obs. of Pleiades stars in SEEDS survey
ID:
ivo://CDS.VizieR/J/PASJ/68/92
Title:
Subaru NIR obs. of Pleiades stars in SEEDS survey
Short Name:
J/PASJ/68/92
Date:
21 Oct 2021
Publisher:
CDS
Description:
We find a new substellar companion to the Pleiades member star, Pleiades HII 3441, using the Subaru telescope with adaptive optics. The discovery is made as part of the high-contrast imaging survey to search for planetary-mass and substellar companions in the Pleiades and young moving groups. The companion has a projected separation of 0.49+/-0.02 (66+/-2au) and a mass of 68+/-5MJ based on three observations in the J-, H-, and Ks-bands. The spectral type is estimated to be M7 (~2700K), and thus no methane absorption is detected in the H band. Our Pleiades observations result in the detection of two substellar companions including one previously reported among 20 observed Pleiades stars, and indicate that the fraction of substellar companions in the Pleiades is about 10.0^+26.1^_-8.8_%. This is consistent with multiplicity studies of both the Pleiades stars and other open clusters.
3644. Subaru-UDGs in the Coma cluster
ID:
ivo://CDS.VizieR/J/ApJS/225/11
Title:
Subaru-UDGs in the Coma cluster
Short Name:
J/ApJS/225/11
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of ultra-diffuse galaxies (UDGs) in the Coma cluster. UDGs are a subset of low surface brightness (SB) galaxies with very large effective radii defined by van Dokkum et al. (2015ApJ...798L..45V). We surveyed the Subaru data archive for deep Suprime-Cam/Subaru R-band images, and used data covering the 1.7x2.7{deg} region of the Coma cluster. The data are ~1 magnitude deeper than the data of van Dokkum et al. in limiting SB. This paper explains the details of our sample selection procedure. This UDG catalog includes positions, magnitudes, effective radii, mean and central SBs, and colors (when available). Comparisons with previous galaxy catalogs in the literature are performed, and we show that the current catalog is the largest for UDGs. We also discuss that most of the UDGs are members of the Coma cluster, and the major axis of the UDGs tends to align toward the cluster center (radial alignment).
3645. Subdwarfs in the SDSS
ID:
ivo://CDS.VizieR/J/AJ/128/426
Title:
Subdwarfs in the SDSS
Short Name:
J/AJ/128/426
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a spectroscopic analysis of nearly 8000 late-type dwarfs in the Sloan Digital Sky Survey. Using the H{alpha} emission line as an activity indicator, we investigate the fraction of active stars as a function of spectral type and find a peak near type M8, confirming previous results.
3646. Substellar population of lambda Ori
ID:
ivo://CDS.VizieR/J/ApJ/610/1064
Title:
Substellar population of lambda Ori
Short Name:
J/ApJ/610/1064
Date:
21 Oct 2021
Publisher:
CDS
Description:
By collecting optical and infrared photometry and low-resolution spectroscopy, we have identified a large number of low-mass stars and brown dwarf candidates belonging to the young cluster (~5Myr) associated with the binary star {lambda} Orionis. The lowest mass object found is an M8.5 with an estimated mass of 0.02M_{Sun}_ (~0.01M_{Sun}_ for objects without spectroscopic confirmation). For those objects with spectroscopy, the measured strength of the H{alpha} emission line follows a distribution similar to other clusters with the same age range, with larger equivalent widths for cooler spectral types.
3647. S5 0716+714 UBVRI photometry
ID:
ivo://CDS.VizieR/J/A+A/402/151
Title:
S5 0716+714 UBVRI photometry
Short Name:
J/A+A/402/151
Date:
21 Oct 2021
Publisher:
CDS
Description:
4854 UBVRI photometric data on the BL Lacertae object S5 0716+71 taken from 8 Observatories in the period 1994-2001 are presented; a table for each optical band is given, containing the observation time, the source magnitude, the error on the source magnitude, and a label indicating the Observatory where the observation was done.
3648. SUDARE-VOICE variability-selection of AGN
ID:
ivo://CDS.VizieR/J/A+A/579/A115
Title:
SUDARE-VOICE variability-selection of AGN
Short Name:
J/A+A/579/A115
Date:
21 Oct 2021
Publisher:
CDS
Description:
One of the most peculiar characteristics of active galactic nuclei (AGNs) is their variability over all wavelengths. This property has been used in the past to select AGN samples and is foreseen to be one of the detection techniques applied in future multi-epoch surveys, complementing photometric and spectroscopic methods. In this paper, we aim to construct and characterise an AGN sample using a multi-epoch dataset in the r band from the SUDARE-VOICE survey. Our work makes use of the VST monitoring programme of an area surrounding the Chandra Deep Field South to select variable sources. We use data spanning a six-month period over an area of 2 square degrees, to identify AGN based on their photometric variability. The selected sample includes 175 AGN candidates with magnitude r<23mag. We distinguish different classes of variable sources through their lightcurves, as well as X-ray, spectroscopic, SED, optical, and IR information overlapping with our survey. We find that 12% of the sample (21/175) is represented by supernovae (SN). Of the remaining sources, 4% (6/154) are stars, while 66% (102/154) are likely AGNs based on the available diagnostics. We estimate an upper limit to the contamination of the variability selected AGN sample =~34%, but we point out that restricting the analysis to the sources with available multi-wavelength ancillary information, the purity of our sample is close to 80% (102 AGN out of 128 non-SN sources with multi-wavelength diagnostics). Our work thus confirms the efficiency of the variability selection method, in agreement with our previous work on the COSMOS field. In addition we show that the variability approach is roughly consistent with the infrared selection.
3649. Sulamitis and Clarissa asteroids spectra
ID:
ivo://CDS.VizieR/J/A+A/610/A25
Title:
Sulamitis and Clarissa asteroids spectra
Short Name:
J/A+A/610/A25
Date:
21 Oct 2021
Publisher:
CDS
Description:
The low-inclination (i<80{deg}) primitive asteroid families in the inner main belt, that is, Polana-Eulalia, Erigone, Sulamitis, and Clarissa, are considered to be the most likely sources of near-Earth asteroids (101955) Bennu and (162173) Ryugu. These two primitive NEAs will be visited by NASA OSIRIS-REx and JAXA Hayabusa 2 missions, respectively, with the aim of collecting samples of material from their surfaces and returning them back to Earth. In this context, the Primitive Asteroid Spectroscopic Survey (PRIMASS) was born, with the main aim to characterize the possible origins of these NEAs and constrain their dynamical evolution. As part of the PRIMASS survey we have already studied the Polana and Erigone collisional families in previously published works. The main goal of the work presented here is to compositionally characterize the Sulamitis and Clarissa families using visible spectroscopy. We have observed 97 asteroids (64 from Sulamitis and 33 from Clarissa) with the OSIRIS instrument (0.5-0.9um) at the 10.4m Gran Telescopio Canarias (GTC). We found that about 60% of the sampled asteroids from the Sulamitis family show signs of aqueous alteration on their surfaces. We also found that the majority of the Clarissa members present no signs of hydration. The results obtained here show similarities between Sulamitis-Erigone, and Clarissa-Polana collisional families.
3650. Sunyaev-Zel'dovich galaxy clusters surveyed by ACT
ID:
ivo://CDS.VizieR/J/ApJS/253/3
Title:
Sunyaev-Zel'dovich galaxy clusters surveyed by ACT
Short Name:
J/ApJS/253/3
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of 4195 optically confirmed Sunyaev-Zel'dovich (SZ) selected galaxy clusters detected with signal-to-noise ratio >4 in 13211deg^2^ of sky surveyed by the Atacama Cosmology Telescope (ACT). Cluster candidates were selected by applying a multifrequency matched filter to 98 and 150GHz maps constructed from ACT observations obtained from 2008 to 2018 and confirmed using deep, wide-area optical surveys. The clusters span the redshift range 0.04<z<1.91 (median z=0.52). The catalog contains 222 z>1 clusters, and a total of 868 systems are new discoveries. Assuming an SZ signal versus mass-scaling relation calibrated from X-ray observations, the sample has a 90% completeness mass limit of M_500c_>3.8x10^14^M_{sun}_, evaluated at z=0.5, for clusters detected at signal-to-noise ratio >5 in maps filtered at an angular scale of 2.4'. The survey has a large overlap with deep optical weak-lensing surveys that are being used to calibrate the SZ signal mass-scaling relation, such as the Dark Energy Survey (4566deg^2^), the Hyper Suprime-Cam Subaru Strategic Program (469deg^2^), and the Kilo Degree Survey (825deg^2^). We highlight some noteworthy objects in the sample, including potentially projected systems, clusters with strong lensing features, clusters with active central galaxies or star formation, and systems of multiple clusters that may be physically associated. The cluster catalog will be a useful resource for future cosmological analyses and studying the evolution of the intracluster medium and galaxies in massive clusters over the past 10Gyr.