- ID:
- ivo://CDS.VizieR/J/A+A/473/149
- Title:
- Photometry of sources in IRAS 16362-4845 cluster
- Short Name:
- J/A+A/473/149
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The IRAS 16362-4845 star-forming site in the RCW 108 complex contains an embedded compact cluster that includes some massive O-type stars. Star formation in the complex, and in particular in IRAS 16362-4845, has been proposed to be externally triggered by the action of NGC 6193. We present a photometric study of the IRAS 16362-4845 cluster sensitive enough to probe the massive brown dwarf regime. In particular, we try to verify an apparent scarcity of solar-type and low-mass stars reported in a previous paper (Comeron et al., 2005A&A...433..955C).
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/123/2822
- Title:
- Photometry of southern NLTT stars
- Short Name:
- J/AJ/123/2822
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present BVRI photometry of 180 bright, southern nearby-star candidates. The stars were selected from the New Luyten Two-Tenths proper-motion catalog (Cat. <I/98>) based on optical/infrared colors, constructed by combining Luyten's m_r_ estimates with near-infrared photometry from the Two Micron All Sky Survey (Cat. <B/2mass>) . Photometric parallaxes derived from V-Ks, V-I, and I-J colors, combined with the limited available astrometry, show that as many as 108 stars may lie within 20pc of the Sun. Of these, 53 are new to nearby-star catalogs, including three within 10pc of the Sun.
- ID:
- ivo://CDS.VizieR/J/ApJ/756/173
- Title:
- Photometry of type IIn SNe 2005ip and 2006jd
- Short Name:
- J/ApJ/756/173
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an observational study of the Type IIn supernovae (SNe IIn) 2005ip and 2006jd. Broadband UV, optical, and near-IR photometry, and visual-wavelength spectroscopy of SN 2005ip complement and extend upon published observations to 6.5 years past discovery. Our observations of SN 2006jd extend from UV to mid-infrared wavelengths, and like SN 2005ip, are compared to reported X-ray measurements to understand the nature of the progenitor. Both objects display a number of similarities with the 1988Z-like subclass of SN IIn including (1) remarkably similar early- and late-phase optical spectra, (2) a variety of high-ionization coronal lines, (3) long-duration optical and near-IR emission, and (4) evidence of cold and warm dust components. However, diversity is apparent, including an unprecedented late-time r-band excess in SN 2006jd. The observed differences are attributed to differences between the mass-loss history of the progenitor stars. We conclude that the progenitor of SN 2006jd likely experienced a significant mass-loss event during its pre-SN evolution akin to the great 19th century eruption of {eta} Carinae. Contrarily, as advocated by Smith et al., the circumstellar environment of SN 2005ip is found to be more consistent with a clumpy wind progenitor.
- ID:
- ivo://CDS.VizieR/J/A+A/567/A73
- Title:
- Photometry of VdBH 222 stars and field stars
- Short Name:
- J/A+A/567/A73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- It has been suggested that the compact open cluster VdBH 222 is a young massive distant object. We set out to characterise VdBH 222 using a comprehensive set of multi-wavelength observations. We obtained multi-band optical (UBVR) and near-infrared (JHKs) photometry of the cluster field, as well as multi-object and long-slit optical spectroscopy for a large sample of stars in the field. We applied classical photometric analysis, as well as more sophisticated methods using the CHORIZOS code, to determine the reddening to the cluster. We then plotted dereddened HR diagrams and determined cluster parameters via isochrone fitting.
- ID:
- ivo://CDS.VizieR/J/A+A/584/A31
- Title:
- Photometry of VVV CL041 cluster
- Short Name:
- J/A+A/584/A31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The ESO Public Survey VISTA Variables in the Via Lactea (VVV) provides deep multi-epoch infrared observations for an unprecedented 562 sq. deg of the Galactic bulge and adjacent regions of the disk. Nearly 150 new open clusters and cluster candidates have been discovered in this survey. We present the fourth article in a series of papers focussed on young and massive clusters discovered in the VVV survey. This article is dedicated to the cluster VVV CL041, which contains a new very massive star candidate, WR 62-2. Following the methodology presented in the first paper of the series, wide-field, deep JHKs VVV observations, combined with new infrared spectroscopy, are employed to constrain fundamental parameters (distance, reddening, mass, age) of VVV CL041.
- ID:
- ivo://CDS.VizieR/J/AJ/143/99
- Title:
- Photometry of W UMa eclipsing binaries
- Short Name:
- J/AJ/143/99
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on a BVRcIc survey of field W Ursae Majoris (UMa) binary stars and present accurate colors for 606 systems that have been observed on at least three photometric nights from a robotic observatory in southern Arizona. Comparison with earlier photometry for a subset of the systems shows good agreement. We investigate two independent methods of determining the interstellar reddening, although both have limitations that can render them less effective than desired. A subset of 101 systems shows good agreement between the two reddening methods.
- ID:
- ivo://CDS.VizieR/J/AJ/145/15
- Title:
- Photometry of YSOs in BRC 27 and BRC 34
- Short Name:
- J/AJ/145/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We used archival Spitzer Space Telescope mid-infrared data to search for young stellar objects (YSOs) in the immediate vicinity of two bright-rimmed clouds, BRC 27 (part of CMa R1) and BRC 34 (part of the IC 1396 complex). These regions both appear to be actively forming young stars, perhaps triggered by the proximate OB stars. In BRC 27, we find clear infrared excesses around 22 of the 26 YSOs or YSO candidates identified in the literature, and identify 16 new YSO candidates that appear to have IR excesses. In BRC 34, the one literature-identified YSO has an IR excess, and we suggest 13 new YSO candidates in this region, including a new Class I object. Considering the entire ensemble, both BRCs are likely of comparable ages, within the uncertainties of small number statistics and without spectroscopy to confirm or refute the YSO candidates. Similarly, no clear conclusions can yet be drawn about any possible age gradients that may be present across the BRCs.
- ID:
- ivo://CDS.VizieR/J/AJ/151/126
- Title:
- Photometry of YSOs in eight bright-rimmed clouds
- Short Name:
- J/AJ/151/126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We carried out deep- and wide-field near- and mid-infrared observations for a sample of eight bright-rimmed clouds (BRCs). Supplemented with the Spitzer archival data, we have identified and classified 44 to 433 young stellar objects (YSOs) associated with these BRCs. The Class I sources are generally located toward the places with higher extinction and are relatively closer to each other than the Class II sources, confirming that the young protostars are usually found in regions with denser molecular material. On the other hand the comparatively older population, Class II objects, are more randomly found throughout the regions, which can be due to their dynamical evolution. Using the minimal sampling tree analyses, we have extracted 13 stellar cores of eight or more members, which contain 60% of the total YSOs. The typical core is ~0.6pc in radii and somewhat elongated (aspect ratio of 1.45), of relatively low stellar density (surface density 60pc^-2^), consisting of a small (35) number of YSOs of relatively young sources (66% Class I), and partially embedded (median A_K_=1.1mag). But the cores show a wide range in their mass distribution (~20 to 2400M_{Sun}_), with a median value of around 130M_{Sun}_. We found the star-formation efficiencies in the cores to be between 3% and 30% with an average of ~14%, which agrees with the efficiencies needed to link the core mass function to the initial mass function. We also found a linear relation between the density of the clouds and the number of YSOs. The peaked nearest neighbor spacing distributions of the YSOs and the ratio of Jeans lengths to the YSO separations indicates a significant degree of non-thermally driven fragmentation in these BRCs.
- ID:
- ivo://CDS.VizieR/J/AJ/159/173
- Title:
- Photometry & RVs of 4 dwarfs hosting giant planets
- Short Name:
- J/AJ/159/173
- Date:
- 09 Dec 2021
- Publisher:
- CDS
- Description:
- We report the discovery of four transiting giant planets around K-dwarfs. The planets HATS-47b, HATS-48Ab, HATS-49b, and HATS-72b have masses of 0.369_-0.021_^+0.031^M_J_, 0.243_-0.030_^+0.022^M_J_, 0.353_-0.027_^+0.038^M_J_, and 0.1254{+/-}0.0039M_J_, respectively, and radii of 1.117{+/-}0.014R_J_, 0.800{+/-}0.015R_J_, 0.765{+/-}0.013R_J_, and 0.7224{+/-}0.0032R_J_, respectively. The planets orbit close to their host stars with orbital periods of 3.9228days, 3.1317days, 4.1480days, and 7.3279days, respectively. The hosts are main-sequence K-dwarfs with masses of 0.674_-0.012_^+0.016^M_{odot}_, 0.7279{+/-}0.0066M_{odot}_, 0.7133{+/-}0.0075M_{odot}_, and 0.7311{+/-}0.0028, and with V-band magnitudes of V=14.829{+/-}0.010, 14.35{+/-}0.11, 14.998{+/-}0.040 and 12.469{+/-}0.010. The super-Neptune HATS-72b (a.k.a. WASP-191b and TOI294.01) was independently identified as a transiting planet candidate by the HATSouth, WASP, and TESS surveys, and we present a combined analysis of all of the data gathered by each of these projects (and their follow-up programs). An exceptionally precise mass is measured for HATS-72b thanks to high-precision radial velocity (RV) measurements obtained with VLT/ESPRESSO, FEROS, HARPS, and Magellan/PFS. We also incorporate TESS observations of the warm Saturn-hosting systems HATS-47 (a.k.a. TOI1073.01), HATS-48A, and HATS-49. HATS-47 was independently identified as a candidate by the TESS team, while the other two systems were not previously identified from the TESS data. The RV orbital variations are measured for these systems using Magellan/PFS. HATS-48A has a resolved 5.4" neighbor in Gaia DR2, which is a common-proper-motion binary star companion to HATS-48A with a mass of 0.22M_{odot}_ and a current projected physical separation of ~1400au.
- ID:
- ivo://CDS.VizieR/J/AJ/117/102
- Title:
- Photometry + Spectroscopy in HDF + Flanking Fields
- Short Name:
- J/AJ/117/102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an HK' wide-field survey encompassing the Hubble Deep Field and its flanking fields. Our wide-field survey provides uniform coverage of a 61.8arcmin^2^ area to a depth equivalent to K=20.1 at 5{sigma}. We have also imaged the Hubble Deep Field in HK', providing uniform coverage of a 7.8arcmin^2^ area to a depth equivalent to K=21.2 at 5{sigma}. Using these data in combination with new deep University of Hawaii 8K V- and I-imaging obtained on the Canada-France-Hawaii Telescope, we find only a small population of objects with colors redder than an equivalent I-K=4mag, the color expected for an evolved elliptical galaxy at z>1. We infer that only a fraction of the local field elliptical galaxy population with M_K_<-23.4 could have formed in single bursts at high redshift. The HK' observations of the HDF and its flanking fields were made with the University of Hawaii 2.2m telescope (1996-02-06 to 1996-02-08 for the HDF, and 1997-04-17 to 1997-04-22 for the wider area) and the 3.6m Canada-France-Hawaii Telescope (CFHT, 1996-04-05 to 1996-04-08 for the HDF). The deep V- and I-band observations were made with the CFHT (1997-04-03 to 1997-04-08), and B-band observations with the Keck Low Resolution Imaging Spectrograph in a strip across the center of the HK wide-field image.
