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801. New infrared star clusters in southern Milky Way
ID:
ivo://CDS.VizieR/J/A+A/400/533
Title:
New infrared star clusters in southern Milky Way
Short Name:
J/A+A/400/533
Date:
21 Oct 2021
Publisher:
CDS
Description:
We carried out a 2MASS J, H and Ks survey of infrared star clusters in the Milky Way sector 230{deg}<l<350{deg}. This zone was the least studied in the literature, previously including only 12 infrared clusters or stellar groups with |b|<10{deg}, according to the recent catalogue by Bica et al. (2003, Cat. <J/A+A/397/177>). We concentrated efforts on embedded clusters, which are those expected in the areas of known radio and optical nebulae. The present study provides 179 new infrared clusters and stellar groups, which are interesting targets for detailed future infrared studies. The sample of catalogued infrared clusters and stellar groups in the Galaxy is now increased by 63%.
802. New L and T dwarfs from the SDSS
ID:
ivo://CDS.VizieR/J/AJ/131/2722
Title:
New L and T dwarfs from the SDSS
Short Name:
J/AJ/131/2722
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present near-infrared observations of 71 newly discovered L and T dwarfs, selected from imaging data of the Sloan Digital Sky Survey (SDSS) using the i-dropout technique. Sixty-five of these dwarfs have been classified spectroscopically according to the near-infrared L dwarf classification scheme of Geballe et al. (2002ApJ...564..466G) and the unified T dwarf classification scheme of Burgasser et al. (2006, Cat. <J/ApJ/637/1067>). The spectral types of these dwarfs range from L3 to T7 and include the latest types yet found in the SDSS. Six of the newly identified dwarfs are classified as early to mid-L dwarfs according to their photometric near-infrared colors, and two others are classified photometrically as M dwarfs. We also present new near-infrared spectra for five previously published SDSS L and T dwarfs, and one L dwarf and one T dwarf discovered by Burgasser et al. (2006, Cat. <J/ApJ/637/1067>) from the Two Micron All Sky Survey. The new SDSS sample includes 27 T dwarfs and 30 dwarfs with spectral types spanning the complex L-T transition (L7-T3).
803. New R Coronae Borealis stars
ID:
ivo://CDS.VizieR/J/A+A/635/A14
Title:
New R Coronae Borealis stars
Short Name:
J/A+A/635/A14
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalogue contains 2356 entries. It was created to list targets of interest that have similar near- and mid-infrared characteristics than R Coronae Borealis (RCB) stars which are hydrogen-deficient carbon-rich supergiant stars known to possess warm circumstellar shells. It is therefore a catalogue enriched in such objects and further spectroscopic follow-ups are needed to reveal the true nature of each target. The catalogue was produced from a series of selection criteria on the infrared colours and brightness of sources published in the WISE All-Sky data release, and also listed in the 2MASS catalogue. These sources spread over the entire sky. The selection criteria are described in section 2 of the paper.
804. New Sample of OH/IR stars
ID:
ivo://CDS.VizieR/J/A+AS/128/35
Title:
New Sample of OH/IR stars
Short Name:
J/A+AS/128/35
Date:
21 Oct 2021
Publisher:
CDS
Description:
Tables 2 and 3 present the positional and kinematic, and physical data for OH/IR stars found within 37 arcmin of the Galactic center (Sgr A*) respectively.
805. New star clusters discovered in the GLIMPSE survey
ID:
ivo://CDS.VizieR/J/ApJ/635/560
Title:
New star clusters discovered in the GLIMPSE survey
Short Name:
J/ApJ/635/560
Date:
21 Oct 2021
Publisher:
CDS
Description:
A systematic and automated search of the extensive GLIMPSE (Galactic Legacy Infrared Mid-Plane Survey Extraordinaire) mid-infrared survey data of the inner Galaxy was carried out to uncover new star clusters. This search has yielded 59 new clusters. Using our automated search algorithm, these clusters were identified as significant localized overdensities in the GLIMPSE point-source catalog (GLMC) and archive (GLMA). Subsequent visual inspection of the GLIMPSE image mosaics confirmed the existence of these clusters plus an additional 33 heavily embedded clusters missed by our detection algorithm, for a total of 92 newly discovered clusters.
806. New star clusters in the central plane region
ID:
ivo://CDS.VizieR/J/ApJ/856/152
Title:
New star clusters in the central plane region
Short Name:
J/ApJ/856/152
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the discovery of new star clusters in the central plane region (|l|<30{deg} and |b|<6{deg}) of the Milky Way. In order to overcome the extinction problem and the spatial limit of previous surveys, we use the Wide-field Infrared Survey Explorer (WISE) data to find clusters. We also use other infrared survey data in the archive for additional analysis. We find 923 new clusters, of which 202 clusters are embedded clusters. These clusters are concentrated toward the Galactic plane and show a symmetric distribution with respect to the Galactic latitude. The embedded clusters show a stronger concentration to the Galactic plane than the nonembedded clusters. The new clusters are found more in the first Galactic quadrant, while previously known clusters are found more in the fourth Galactic quadrant. The spatial distribution of the combined sample of known clusters and new clusters is approximately symmetric with respect to the Galactic longitude. We estimate reddenings, distances, and relative ages of the 15 class A clusters using theoretical isochrones. Ten of them are relatively old (age >800Myr) and five are young (age ~4Myr).
807. New Taurus members from stellar to planetary masses
ID:
ivo://CDS.VizieR/J/AJ/158/54
Title:
New Taurus members from stellar to planetary masses
Short Name:
J/AJ/158/54
Date:
06 Dec 2021 11:31:43
Publisher:
CDS
Description:
We present a large sample of new members of the Taurus star-forming region that extend from stellar to planetary masses. To identify candidate members at substellar masses, we have used color-magnitude diagrams and proper motions measured with several wide-field optical and infrared (IR) surveys. At stellar masses, we have considered the candidate members that were found in a recent analysis of high-precision astrometry from the Gaia mission. Using new and archival spectra, we have measured spectral types and assessed membership for these 161 candidates, 79 of which are classified as new members. Our updated census of Taurus now contains 519 known members. According to Gaia data, this census should be nearly complete for spectral types earlier than M6-M7 at A_J_<1. For a large field encompassing ~72% of the known members, the census should be complete for K<15.7 at A_J_<1.5, which corresponds to ~5-13 M_Jup_ for ages of 1-10 Myr based on theoretical evolutionary models. Our survey has doubled the number of known members at >=M9 and has uncovered the faintest known member in M_K_, which should have a mass of ~3-10 M_Jup_ for ages of 1-10 Myr. We have used mid-IR photometry from the Spitzer Space Telescope and the Wide-field Infrared Survey Explorer to determine whether the new members exhibit excess emission that would indicate the presence of circumstellar disks. The updated disk fraction for Taurus is ~0.7 at =<M3.5 and ~0.4 at >M3.5.
808. New T dwarfs identified in Pan-STARRS 1
ID:
ivo://CDS.VizieR/J/AJ/142/77
Title:
New T dwarfs identified in Pan-STARRS 1
Short Name:
J/AJ/142/77
Date:
21 Oct 2021
Publisher:
CDS
Description:
A complete well-defined sample of ultracool dwarfs is one of the key science programs of the Pan-STARRS 1 optical survey telescope (PS1). Here we combine PS1 commissioning data with the Two Micron All Sky Survey (2MASS) to conduct a proper motion search (0.1-2.0"/yr) for nearby T dwarfs, using optical+near-IR colors to select objects for spectroscopic follow-up. The addition of sensitive far-red optical imaging from PS1 enables discovery of nearby ultracool dwarfs that cannot be identified from 2MASS data alone. We have searched 3700deg^2^ of PS1 y-band (0.95-1.03um) data to y~19.5mag (AB) and J~16.5mag (Vega) and discovered four previously unknown bright T dwarfs. Three of the objects (with spectral types T1.5, T2, and T3.5) have photometric distances within 25pc and were missed by previous 2MASS searches due to more restrictive color selection criteria. The fourth object (spectral type T4.5) is more distant than 25pc and is only a single-band detection in 2MASS. We also examine the potential for completing the census of nearby ultracool objects with the PS1 3{PI} survey.
809. New ultra-cool dwarfs from SDSS and 2MASS
ID:
ivo://CDS.VizieR/J/A+A/497/619
Title:
New ultra-cool dwarfs from SDSS and 2MASS
Short Name:
J/A+A/497/619
Date:
21 Oct 2021
Publisher:
CDS
Description:
We try to identify ultra-cool dwarfs from the seventh Data Release of the Sloan Digital Sky Survey (SDSS DR7) with SDSS i-z and r-z colors. We also obtain proper motion data from SDSS, 2MASS, and UKIDSS and improve spectral typing from SDSS and 2MASS photometric colors.
810. New young stellar cluster towards IRAS 04186+5143
ID:
ivo://CDS.VizieR/J/MNRAS/452/1523
Title:
New young stellar cluster towards IRAS 04186+5143
Short Name:
J/MNRAS/452/1523
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the discovery of a new young stellar cluster in the outer Galaxy located at the position of an IRAS Point Source Catalog source that has been previously misidentified as an external galaxy. The cluster is seen in our near-infrared imaging towards IRAS 04186+5143 and in archive Spitzer images confirming the young stellar nature of the sources detected. There is also evidence of subclustering seen in the spatial distributions of young stars and of gas and dust. Near- and mid-infrared photometry indicates that the stars exhibit colours compatible with reddening by interstellar and circumstellar dust and are likely to be low- and intermediate-mass young stellar objects (YSOs) with a large proportion of Class I YSOs. Ammonia and CO lines were detected, with the CO emission well centred near the position of the richest part of the cluster. The velocity of the CO and NH3 lines indicates that the gas is Galactic and located at a distance of about 5.5kpc, in the outer Galaxy. Herschel data of this region characterize the dust environment of this molecular cloud core where the young cluster is embedded. We derive masses, luminosities, and temperatures of the molecular clumps where the young stars reside and discuss their evolutionary stages.