- ID:
- ivo://CDS.VizieR/J/AJ/157/111
- Title:
- Study of three early-type contact twin binaries
- Short Name:
- J/AJ/157/111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Three eclipsing binaries, CT Tau, GU Mon, and V701 Sco, are early-type contact binaries with infrared excess from circumbinary matter. We present the multi-color photometry for CT Tau and GU Mon, whose spectral types of B1V are identified by the low-precision spectra. Combining these new light curves (LCs) with previously reported LCs and radial velocity curves, we perform a synthesized analysis to estimate/update the stellar absolute parameters of the three systems. Their mass ratios are close to unity (i.e., q~1), which indicates that the binary system comprising of twin components may be undergoing a slow Case A mass transfer. From the period analysis, the light-time orbit in the (O-C) curve may result from the third condense companion around the binary system although no evidence could be provided by the third light l_3_. From the spectral energy distribution for three binaries, the excess infrared (IR) emissions are above the photospheric emissions, which can be seen at the 22.1 {mu}m for CT Tau and GU Mon, and 11.6 {mu}m, 14.5 {mu}m, and 22.1 {mu}m for V701 Sco, respectively. This kind of infrared excess for the early-type star may be attributed to the circumbinary matter by stellar wind.
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20992. Study of Two HgMn Stars
- ID:
- ivo://CDS.VizieR/J/AZh/71/588
- Title:
- Study of Two HgMn Stars
- Short Name:
- J/AZh/71/588
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Three spectra of HD182308 (HR 7361) and four spectra of HD178065 (HR 7245) were obtained from 1989 to 1990 with the Main Stellar Spectrograph of the 6-m telescope at the Special Astrophysical Observatory and with the Coude spectrograph of the 2-m telescope of the Rozhen Observatory of the Bulgarian Academy of Sciences. Spectra were obtained in the range of 3700-4900A with inverse dispersion of 9 A/mm. Spectral resolution was close to 0.25A. Elemental abundances of two HgMn stars, HD 178065 and HD 182308, were found. Objects: --------------------------------------- RA (2000) DE Designation(s) --------------------------------------- 19 19 46.03 +64 23 26.7 HD 182308 19 07 08.95 +00 38 29.3 HD 178065 ---------------------------------------
20993. S-type AGB stars in SMC
- ID:
- ivo://CDS.VizieR/J/ApJ/810/116
- Title:
- S-type AGB stars in SMC
- Short Name:
- J/ApJ/810/116
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have identified a new class of Asymptotic Giant Branch (AGB) stars in the Small and Large Magellanic Clouds (SMC/LMC) using optical to infrared photometry, light curves, and optical spectroscopy. The strong dust production and long-period pulsations of these stars indicate that they are at the very end of their AGB evolution. Period-mass-radius relations for the fundamental-mode pulsators give median current stellar masses of 1.14M_{sun}_ in the LMC and 0.94M_{sun}_ in the SMC (with dispersions of 0.21 and 0.18M_{sun}_, respectively), and models suggest initial masses of <1.5M_{sun}_ and <1.25 M_{sun}_, respectively. This new class of stars includes both O-rich and C-rich chemistries, placing the limit where dredge-up allows carbon star production below these masses. A high fraction of the brightest among them should show S star characteristics indicative of atmospheric C/O~1, and many will form O-rich dust prior to their C-rich phase. These stars can be separated from their less-evolved counterparts by their characteristically red J-[8] colors.
- ID:
- ivo://CDS.VizieR/J/MNRAS/439/1648
- Title:
- Subarcsecond mid-infrared atlas of local AGN
- Short Name:
- J/MNRAS/439/1648
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first subarcsecond-resolution mid-infrared (MIR) atlas of local active galactic nuclei (AGN). Our atlas contains 253 AGN with a median redshift of z=0.016, and includes all publicly available MIR imaging performed to date with ground-based 8-m class telescopes, a total of 895 independent measurements. Of these, more than 60% are published here for the first time. We detect extended nuclear emission in at least 21% of the objects, while another 19% appear clearly point-like, and the remaining objects cannot be constrained. Where present, elongated nuclear emission aligns with the ionization cones in Seyferts. Subarcsecond resolution allows us to isolate the AGN emission on scales of a few tens of parsecs and to obtain nuclear photometry in multiple filters for the objects. Median spectral energy distributions (SEDs) for the different optical AGN types are constructed and individual MIR 12 and 18um continuum luminosities are computed. These range over more than six orders of magnitude. In comparison to the arcsecond-scale MIR emission as probed by Spitzer, the continuum emission is much lower on subarcsecond scales in many cases. The silicate feature strength is similar on both scales and generally appears in emission (absorption) in type I (II) AGN. However, the polycyclic aromatic hydrocarbon emission appears weaker or absent on subarcsecond scales. The differences of the MIR SEDs on both scales are particularly large for AGN/starburst composites and close-by (and weak) AGN. The nucleus dominates over the total emission of the galaxy only at luminosities >~10^44^erg/s. The AGN MIR atlas is well suited not only for detailed investigation of individual sources but also for statistical studies of AGN unification.
- ID:
- ivo://jvo/subaru/hds
- Title:
- Subaru HDS Spectrum data service
- Short Name:
- SubaruHDS
- Date:
- 24 Jul 2024 03:30:55
- Publisher:
- JVO
- Description:
- This data service provides various data related to Subaru HDS.
20996. Subaru H images of UM673
- ID:
- ivo://CDS.VizieR/J/A+A/566/A36
- Title:
- Subaru H images of UM673
- Short Name:
- J/A+A/566/A36
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We performed a detailed photometric analysis of the lensed system UM673 (Q0142-100) and an analysis of the tentative lens models. High-resolution adaptive optics images of UM673 taken with the Subaru telescope in the H band were examined. We also analysed the J, H and K-band observational data of UM673 obtained with the 1.3m telescope at the CTIO observatory. We present photometry of quasar components A and B of UM673, the lens, and the nearby bright galaxy using H-band observational data obtained with the Subaru telescope. Based on the CTIO observations of UM673, we also present J- and H-band photometry and estimates of the J, H and K-band flux ratios between the two UM673 components in recent epochs. The near-infrared fluxes of the A and B components of UM673 and their published optical fluxes are analysed to measure extinction properties of the lensing galaxy. We estimate the extinction-corrected flux ratio between components A and B to be about 2.14 mag. We discuss lens models for the UM673 system constrained with the positions of the UM673 components, their flux ratio, and the previously measured time delay.
- 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.
20998. Subaru MOIRCS data service
- ID:
- ivo://jvo/subaru/moircs
- Title:
- Subaru MOIRCS data service
- Short Name:
- SUBARU_MOIRCS
- Date:
- 14 Nov 2019 03:50:26
- Publisher:
- JVO
- Description:
- MOIRCS (Multi-Object InfraRed Camera and Spectrograph) provides wide-field imaging and long-slit / multi-object (MOS) spectroscopic capabilities in the 0.9 ~ 2.5 µm spectral range under the natural seeing condition. The 4'?~7' field of view is covered by two Hawaii-2 2048?~2048 arrays with the spatial resolution of 0.117 arcsec/pixel.
- 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.
- 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.
