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101. UBV photometry of OB associations in LMC superbubbles
ID:
ivo://CDS.VizieR/J/ApJS/104/71
Title:
UBV photometry of OB associations in LMC superbubbles
Short Name:
J/ApJS/104/71
Date:
21 Oct 2021
Publisher:
CDS
Description:
This work presents UBV photometry of the stellar populations associated with seven superbubble nebulae and five classical H II regions in the Large Magellanic Cloud. Although the nebular morphology of the superbubbles appears to be substantially evolved compared to the classical nebulae, the color-magnitude diagrams do not reveal any noticeable correlation between the resident stellar population and nebular morphology. The photometry presented here will be used in a forthcoming paper to examine further the stellar content and dynamics of these superbubbles.
102. Ultraviolet Imaging Telescope
ID:
ivo://archive.stsci.edu/uit
Title:
Ultraviolet Imaging Telescope
Short Name:
UIT
Date:
22 Jul 2020 21:32:30
Publisher:
Space Telescope Science Institute Archive
Description:
The Ultraviolet Imaging Telescope UIT was one of three ultraviolet telescopes on the ASTRO-1 mission flown on the space shuttle Columbia during 2-10 December 1990. The same three instruments were later flown on the space shuttle Endeavour from 3-17 March 1995, as part of the ASTRO-2 mission. Exposures were obtained on 70-mm photographic film in the 1200-3300 Å range using broadband filters and later digitized using a Perkin-Elmer microdensitometer. Image resolution was 3" over a 40' field of view. Overall, UIT-1 obtained 821 exposures of 66 targets, and UIT-2 obtained 758 images of 193 targets.
103. Updated cat. of extended objects in Magellanic clouds
ID:
ivo://CDS.VizieR/J/AJ/159/82
Title:
Updated cat. of extended objects in Magellanic clouds
Short Name:
J/AJ/159/82
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of star clusters, associations, and related extended objects in the Small Magellanic Cloud (SMC) and the Magellanic Bridge with 2741 entries, a factor 2 more than a previous version from a decade ago. Literature data up until 2018 December are included. The identification of star clusters was carried out with digital atlases in various bands currently available in the Digitized Sky Survey (DSS) and the Machine Automatique a Mesurer pour l'Astronomie (MAMA) imaging surveys. In particular, we cross-identified recent cluster samples from the Visible and Infrared Survey Telescope for Astronomy (VISTA) near-infrared YJKs survey of the Magellanic System (VMC; Rubele+, 2015, J/MNRAS/449/639), Optical Gravitational Lensing Experiment IV (OGLE IV; Sitek+ 2017, J/AcA/67/363), and Survey of the MAgellanic Stellar History (SMASH; Piatti 2017ApJ...834L..14P) surveys, confirming new clusters and pointing out equivalencies. A major contribution of the present catalog consists of the accurate central positions for clusters and small associations, including a new sample of 45 clusters or candidates in the SMC and 19 in the Magellanic Bridge, as well as a compilation of the most reliable age and metallicity values from the literature. A general catalog must also deal with the recent discoveries of 27 faint and ultra-faint star clusters and galaxies projected on the far surroundings of the Clouds, most of them from the Dark Energy Survey. The information on these objects has been complemented with photometric, spectroscopic, and kinematical follow-up data from the literature. The underluminous galaxies around the Magellanic System, still very few as compared to the predictions from {Lambda} Cold Dark Matter simulations, can bring constraints to galaxy formation and hierarchical evolution. Furthermore, we provide diagnostics, when possible, of the nature of the ultra-faint clusters, searching for borders of the Magellanic System extensions into the Milky Way gravitational potential.
104. Variables and Nebulae in Sgr B
ID:
ivo://CDS.VizieR/J/A+AS/76/205
Title:
Variables and Nebulae in Sgr B
Short Name:
J/A+AS/76/205
Date:
21 Oct 2021
Publisher:
CDS
Description:
(no description available)
105. Variables and Nebulae in Sgr B
ID:
ivo://CDS.VizieR/J/A+AS/90/451
Title:
Variables and Nebulae in Sgr B
Short Name:
J/A+AS/90/451
Date:
21 Oct 2021
Publisher:
CDS
Description:
(no description available)
106. Very low-mass YSOs in NGC 1333
ID:
ivo://CDS.VizieR/J/AJ/136/1372
Title:
Very low-mass YSOs in NGC 1333
Short Name:
J/AJ/136/1372
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a deep near-infrared (NIR) imaging survey searching for very low mass young stellar objects (YSOs) in the embedded cluster associated with the Perseus molecular cloud. Our observations cover an area of ~5'x5' in the NGC 1333-S region at J-, H-, and Ks-bands. The 10{sigma} limiting magnitudes exceed 18mag in all three bands. Based on NIR color-color diagrams, embedded YSO candidates were identified using NIR excesses.
107. Vilnius photometry in IC 59 and IC 63
ID:
ivo://CDS.VizieR/J/AJ/161/149
Title:
Vilnius photometry in IC 59 and IC 63
Short Name:
J/AJ/161/149
Date:
20 Jan 2022
Publisher:
CDS
Description:
Optical and infrared continuum polarization from the interstellar medium is driven by radiative processes aligning the grains with the magnetic field. While a quantitative, predictive theory of radiative alignment torques (RATs) exists and has been extensively tested, several parameters of the theory remain to be fully constrained. In a recent paper, Medan & Andersson showed that the polarization efficiency (and therefore grain alignment efficiency) at different locations in the wall of the Local Bubble (LB) could be modeled as proportional to the integrated light intensity from the surrounding stars and OB associations. Here we probe that relationship at high radiation field intensities by studying the extinction and polarization in the two reflection nebulae IC59 and IC63 in the Sh2-185 HII region, illuminated by the B0 IV star {gamma}Cassiopeia. We combine archival visual polarimetry with new seven-band photometry in the Vilnius system, to derive the polarization efficiency from the material. We find that the same linear relationship seen in the LB wall also applies to the Sh2-185 region, strengthening the conclusion from the earlier study.
108. Vilnius Photometry in two Nebulae
ID:
ivo://CDS.VizieR/II/196
Title:
Vilnius Photometry in two Nebulae
Short Name:
II/196
Date:
21 Oct 2021
Publisher:
CDS
Description:
The results of photoelectric photometry of 564 stars in the Vilnius seven-color system in three areas near the North America and Pelican nebulae are given. Photometric spectral types, absolute magnitudes, colour excesses, interstellar extinctions and distances of the stars are determined. We find that the dark cloud separating both nebulae is at 580pc distance. A number of stars immersed into the dark cloud have been found. It seems that the dark cloud extends to south down to 40deg declination. The area southwest of {alpha} Cyg in the declination zones 42 and 43deg is comparatively transparent at least up to 1kpc.
109. V1647 Ori long-term optical & NIR observations
ID:
ivo://CDS.VizieR/J/ApJ/778/116
Title:
V1647 Ori long-term optical & NIR observations
Short Name:
J/ApJ/778/116
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a detailed study of McNeil's nebula (V1647 Ori) in its ongoing outburst phase starting from 2008 September to 2013 March. Our 124 nights of photometric observations were carried out in optical V, R, I, and near-infrared J, H, K bands, and 59 nights of medium-resolution spectroscopic observations were done in the 5200-9000{AA} wavelength range. All observations were carried out with the 2m Himalayan Chandra Telescope and 2m IUCAA Girawali Telescope. Our observations show that over the past four and a half years, V1647 Ori and region C near the Herbig-Haro object HH 22A have been undergoing a slow dimming at a rate of ~0.04mag/yr and ~0.05mag/yr, respectively, in R band, which is six times slower than the rate during a similar stage of V1647 Ori in the 2003 outburst. We detected change in flux distribution over the reflection nebula, implying changes in circumstellar matter distribution between the 2003 and 2008 outbursts. Apart from steady wind of velocity ~350km/s, we detected two episodic magnetic reconnection driven winds. Forbidden [OI]{lambda}6300 and [FeII]{lambda}7155 lines were also detected, implying shock regions probably from jets. We tried to explain the outburst timescales of V1647 Ori using the standard models of the FUors kind of outburst and found that pure thermal instability models like Bell and Lin cannot explain the variations in timescales. In the framework of various instability models we conclude that one possible reason for the sudden ending of the 2003 outburst in 2005 November was a low-density region or gap in the inner region (~1AU) of the disk.
110. VRI photometry in NGC 7129
ID:
ivo://CDS.VizieR/J/AJ/149/200
Title:
VRI photometry in NGC 7129
Short Name:
J/AJ/149/200
Date:
21 Oct 2021
Publisher:
CDS
Description:
NGC7129 is a bright reflection nebula located in the molecular cloud complex near l=105.4{deg}, b=+9.9{deg}, about 1.15kpc distant. Embedded within the reflection nebula is a young cluster dominated by a compact grouping of four early-type stars: BD+65{deg}1638 (B3V), BD+65{deg}1637 (B3e), SVS 13 (B5e), and LkH{alpha} 234 (B8e). About 80 H{alpha} emission sources brighter than V~23 are identified in the region, many of which are presumably T Tauri star members of the cluster. We also present deep (V~23), optical (VR_C_I_C_) photometry of a field centered on the reflection nebula and spectral types for more than 130 sources determined from low dispersion, optical spectroscopy. The narrow pre-main sequence evident in the color-magnitude diagram suggests that star formation was rapid and coeval. A median age of about 1.8Myr is inferred for the H{alpha} and literature-identified X-ray emission sources having established spectral types, using pre-main sequence evolutionary models. Our interpretation of the structure of the molecular cloud and the distribution of young stellar objects is that BD+65{deg}1638 is primarily responsible for evacuating the blister-like cavity within the molecular cloud. LkH{alpha} 234 and several embedded sources evident in near-infrared adaptive optics imaging have formed recently within the ridge of compressed molecular gas. The compact cluster of low-mass stars formed concurrently with the early-type members, concentrated within a central radius of ~0.7pc. Star formation is simultaneously occurring in a semi-circular arc some ~3pc in radius that outlines remaining dense regions of molecular gas. High dispersion, optical spectra are presented for BD+65{deg}1638, BD+65{deg}1637, SVS 13, LkH{alpha} 234, and V350 Cep. These spectra are discussed in the context of the circumstellar environments inferred for these stars.