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4271. New high proper motion stars (-90<DE< -47)
ID:
ivo://CDS.VizieR/J/AJ/129/413
Title:
New high proper motion stars (-90<DE< -47)
Short Name:
J/AJ/129/413
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the discovery of 141 new high proper motion systems ({mu}>=0.4"/yr) in the southern sky (DE=-90 to -47{deg}) brighter than UKST plate R_59F_=16.5 via our SuperCOSMOS-RECONS search. When combined with the nine systems having {mu}>=1.0"/yr and/or late spectral type from the initial phases of this effort, we find that 73 of the 150 total systems are moving faster than 0.5"/yr and are therefore new members of the classic Luyten Half-Second sample. These constitute a 21% increase in the sample of stars with {mu}>=0.5"/yr in the declination region searched, thereby comprising an important addition to this long-neglected region of the sky. Distance estimates are provided for the entire sample, based on a combination of photographic plate magnitudes and Two Micron All Sky Survey photometry, using the relations recently presented by Hambly et al. for the presumed main-sequence stars. Three systems are anticipated to be within 10pc, and an additional 15 are within 25pc. Nine of these 18 nearby systems have proper motions falling between 0.4"/yr and 0.6"/yr, hinting at a large population of nearby stars with fast, but not extremely high, proper motions that have not been thoroughly investigated.
4272. New high proper motion stars (-47<{delta}<00)
ID:
ivo://CDS.VizieR/J/AJ/130/1658
Title:
New high proper motion stars (-47<{delta}<00)
Short Name:
J/AJ/130/1658
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the discovery of 152 new high proper motion systems ({mu}>=0.4"/yr) in the southern sky ({delta}=-47{deg} to 00{deg}) brighter than UKST plate R_59F_=16.5 via our SuperCOSMOS-RECONS (SCR) search. This paper complements Paper XII (2005, Cat. <J/AJ/129/413>) in the Solar Neighborhood series, which covered the region from {delta}=-90{deg} to -47{deg} and discussed all 147 new systems from the southernmost phase of the search. Among the total of 299 systems from both papers, there are 148 (71 in Paper XII (2005, Cat. <J/AJ/129/413>), 77 in this paper) new systems moving faster than 0.5"/yr that are additions to the classic Luyten Half Second sample (1979, Cat. <I/87>). These constitute an 8% increase in the sample of all stellar systems with {mu}>=0.5"/yr in the southern sky.
4273. New high proper motion stars in the northern sky
ID:
ivo://CDS.VizieR/J/AJ/125/1598
Title:
New high proper motion stars in the northern sky
Short Name:
J/AJ/125/1598
Date:
21 Oct 2021
Publisher:
CDS
Description:
We define an enhanced spectral classification scheme for M dwarf stars and use it to derive spectral classification of 104 northern stars with proper motions larger than 0.5"/yr that we discovered in a survey of high proper motion stars at low Galactic latitudes. The final tally is as follows: 54 M dwarfs, 25 sdK and sdM subdwarfs, 14 esdK and esdM extreme subdwarfs, and 11 DA and DC white dwarfs. Among the most interesting cases, we find one star to be the coolest subdwarf ever reported (LSR 2036+5059, with spectral type sdM7.5), a new M9.0 dwarf only about 6 pc distant (LSR 1835+3259), and a new M6.5 dwarf only 7 pc from the Sun (LSR 2124+4003). Spectroscopic distances suggests that 27 of the M dwarfs, three of the white dwarfs, and one of the subdwarfs (LSR 2036+5059) are within 25 pc of the Sun, making them excellent candidates for inclusion in the solar neighborhood census. Estimated sky-projected velocities suggest that most of our subdwarfs and extreme subdwarfs have halo kinematics. We find that several white dwarfs and nonmetal-poor M dwarfs also have kinematics consistent with the halo, and we briefly discuss their possible origin.
4274. New hot subdwarf stars
ID:
ivo://CDS.VizieR/J/MNRAS/457/3396
Title:
New hot subdwarf stars
Short Name:
J/MNRAS/457/3396
Date:
21 Oct 2021
Publisher:
CDS
Description:
Recent massive sky surveys in different bandwidths are providing new opportunities to modern astronomy. The Virtual Observatory (VO) represents the adequate framework to handle the huge amount of information available and filter out data according to specific requirements. In this work, we applied a selection strategy to find new, uncatalogued hot subdwarfs making use of VO tools. We used large area catalogues like GALEX, Sloan Digital Sky Survey (SDSS), SuperCosmos and Two Micron All Sky Survey (2MASS) to retrieve photometric and astrometric information of stellar objects. To these objects, we applied colour and proper motion filters, together with an effective temperature cutoff, aimed at separating hot subdwarfs from other blue objects such as white dwarfs, cataclysmic variables or main-sequence OB stars. As a result, we obtained 437 new, uncatalogued hot subdwarf candidates. Based on previous results, we expect our procedure to have an overall efficiency of at least 80 per cent. Visual inspection of the 68 candidates with SDSS spectrum showed that 65 can be classified as hot subdwarfs: 5 sdOs, 25 sdOBs and 35 sdBs. This success rate above 95 per cent proves the robustness and efficiency of our methodology. The spectral energy distribution of 45 per cent of the subdwarf candidates showed infrared excesses, a signature of their probable binary nature. The stellar companions of the binary systems so detected are expected to be late-type main-sequence stars. A detailed determination of temperatures and spectral classification of the cool companions will be presented in a forthcoming work.
4275. New hot subdwarf stars
ID:
ivo://CDS.VizieR/J/A+A/530/A2
Title:
New hot subdwarf stars
Short Name:
J/A+A/530/A2
Date:
21 Oct 2021
Publisher:
CDS
Description:
Recent massive sky surveys in different bandwidths are providing new opportunities to modern astronomy. The Virtual Observatory (VO) provides the adequate framework to handle the huge amount of information available and filter out data according to specific requirements. Hot subdwarf stars are faint, blue objects, and are the main contributors to the far-UV excess observed in elliptical galaxies. They offer an excellent laboratory to study close and wide binary systems, and to scrutinize their interiors through asteroseismology, since some of them undergo stellar oscillations. However, their origins are still uncertain, and increasing the number of detections is crucial to undertake statistical studies. In this work, we aim at defining a strategy to find new, uncatalogued hot subdwarfs.
4276. New infrared carbon stars in IRAS PSC
ID:
ivo://CDS.VizieR/J/A+AS/122/489
Title:
New infrared carbon stars in IRAS PSC
Short Name:
J/A+AS/122/489
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present new results of a search for infrared carbon stars (IRCS) based on the combination of IRAS and near infrared colours. A sample of 207 stars with IRAS colours that characterize IRCS is selected and measured in the JHKL photometric bands. Using a [12-25] vs. K-L colour diagram, 20 new IRCS candidates are proposed. Medium resolution spectra in the ~6000-9000{AA} range of 8 of these candidates confirm their carbon rich nature. In addition we propose a few stars with LRS class "4n" as oxygen-rich candidates, and a few stars with LRS classes "0n" and "1n" as carbon-rich.
4277. New IR photometric study of Ap and Am stars
ID:
ivo://CDS.VizieR/J/AJ/153/218
Title:
New IR photometric study of Ap and Am stars
Short Name:
J/AJ/153/218
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper, 426 well known confirmed Ap and Am stars are photometrically studied in the infrared. The 2MASS, Wide-field Infrared Survey Explorer (WISE), and IRAS data are employed to make analyses. The results in this paper have shown that in the 1-3 {mu}m region over 90% Ap and Am stars have no or little infrared excesses, and infrared radiations in the near-infrared from these stars are probably dominated by the free-free emissions. It is also shown that in the 3-12 {mu}m region, the majority of Ap stars and Am stars have very similar behavior, i.e., in the W1-W2 (3.4-4.6 {mu}m) region, over half of Ap and Am stars have clear infrared excesses, which are possibly due to the binarity, the multiplicity, and/or the debris disk, but in the W2-W3 (4.6-12 {mu}m) region they have no or little infrared excess. In addition, in the 12-22 {mu}m region, some of Ap stars and Am stars show the infrared excesses and infrared radiations for these Ap and Am stars are probably due to the free-free emissions. In addition, it is seen that the probability of being the binarity, the multiplicity and/or the debris disk for Am stars is much higher than that for Ap stars. Furthermore, it can be seen that, in general, no relations can be found between infrared colors and spectral types either for Ap stars or for Am stars.
4278. 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).
4279. New lens candidates in CFHTLS
ID:
ivo://CDS.VizieR/J/A+A/592/A75
Title:
New lens candidates in CFHTLS
Short Name:
J/A+A/592/A75
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a new search for galaxy-scale strong lensing systems in CFHTLS Wide. Our lens-finding technique involves a preselection of potential lens galaxies, applying simple cuts in size and magnitude. We then perform a Principal Component Analysis of the galaxy images, ensuring a clean removal of the light profile. Lensed features are searched for in the residual images using the clustering topometric algorithm DBSCAN. We find 1098 lens candidates that we inspect visually, leading to a cleaned sample of 109 new lens candidates. Using realistic image simulations we estimate the completeness of our sample and show that it is independent of source surface brightness, Einstein ring size (image separation) or lens redshift. We compare the properties of our sample to previous lens searches in CFHTLS. Including the present search, the total number of lenses found in CFHTLS amounts to 678, which corresponds to ~4 lenses per square degree down to i(AB)=24.8. This is equivalent to ~60.000 lenses in total in a survey as wide as Euclid, but at the CFHTLS resolution and depth.
4280. New light elements for 28 red periodic var.
ID:
ivo://CDS.VizieR/J/other/PZP/9.6
Title:
New light elements for 28 red periodic var.
Short Name:
J/other/PZP/9.6
Date:
21 Oct 2021
Publisher:
CDS
Description:
We could study the variables thanks to the publicly available electronic archives of CCD observations of the ASAS-3 project (Pojmanski 2002, Cat. <II/264>) and to images of the US Naval Observatory Image and Catalogue Archive (https://www.usno.navy.mil/USNO/astrometry/optical-IR-prod/icas). We recovered the variables NSV 07168, NSV 07291, NSV 07352, NSV 07388 and NSV 07406 suspected by Luyten (1933AN....249..395L); NSV 07161, NSV 07188, NSV 07203, NSV 07208, NSV 07260, NSV 07286, NSV 07347, NSV 07387, NSV 07392 and NSV 07422 suspected by Luyten (1933AN....250..259L); NSV 07130, NSV 07228, NSV 07238 and NSV 07425 suspected by Luyten (1934AN....253..135L); NSV 07117, NSV 07131, NSV 07137 and NSV 07382 suspected by Luyten (1935AN....256..325L); NSV 07411 suspected by Luyten (1936AN....258..121L); NSV 07309 suspected by Luyten (1937AN....261..451L); NSV 07353 suspected by Luyten (1937AN....263..181L). Finding charts for these suspected variables have never been published.