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2321. New planetary nebulae in LMC
ID:
ivo://CDS.VizieR/J/MNRAS/365/401
Title:
New planetary nebulae in LMC
Short Name:
J/MNRAS/365/401
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report our initial discovery of 73 new planetary nebulae (PNe) in the Large Magellanic Cloud (LMC) following confirmatory 2dF spectroscopy on the Anglo-Australian Telescope. Preliminary candidate sources come from a 10 per cent sub-area of our new deep, high-resolution H{alpha} map of the central 25deg^2^ of the LMC obtained with the UK Schmidt Telescope. The depth of the high-resolution map was extended to R_equiv_~22 for H{alpha} (4.5x10^-17^erg/cm^2^/s/{AA}) by a process of multi-exposure median co-addition of a dozen 2-h H{alpha} exposures. The resulting map is at least 1-mag deeper than the best wide-field narrow-band LMC images currently available. This depth, combined with our selection technique, has also led to the discovery of extended asymptotic giant branch (AGB) haloes around many new and previously known LMC PNe for the first time. Once complete, our new survey is expected to triple the LMC PN population and have significant implications for the LMC PN luminosity function, kinematics, abundance gradients, chemical evolution and, via study of the AGB haloes, the initial to final mass relation for low- to intermediate-mass stars.
2322. 181 new planet candidates with TESS
ID:
ivo://CDS.VizieR/J/AJ/161/273
Title:
181 new planet candidates with TESS
Short Name:
J/AJ/161/273
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Transiting Exoplanet Survey Satellite (TESS) mission measured light from stars in ~75% of the sky throughout its 2yr primary mission, resulting in millions of TESS 30-minute-cadence light curves to analyze in the search for transiting exoplanets. To search this vast data trove for transit signals, we aim to provide an approach that both is computationally efficient and produces highly performant predictions. This approach minimizes the required human search effort. We present a convolutional neural network, which we train to identify planetary transit signals and dismiss false positives. To make a prediction for a given light curve, our network requires no prior transit parameters identified using other methods. Our network performs inference on a TESS 30-minute-cadence light curve in ~5ms on a single GPU, enabling large-scale archival searches. We present 181 new planet candidates identified by our network, which pass subsequent human vetting designed to rule out false positives. Our neural network model is additionally provided as open-source code for public use and extension.
2323. New SDSS and Washington photometry in Segue 3
ID:
ivo://CDS.VizieR/J/AJ/154/57
Title:
New SDSS and Washington photometry in Segue 3
Short Name:
J/AJ/154/57
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present new SDSS and Washington photometry of the young outer-halo stellar system Segue 3. Combined with archival VI-observations, our most consistent results yield Z=0.006+/-0.001, log(Age)=9.42+/-0.08, (m-M)_0_=17.35+/-0.08, and E(B-V)=0.09+/-0.01, with a high binary fraction of 0.39+/-0.05 derived using the Padova models. We confirm that mass-segregation has occurred, supporting the hypothesis that this cluster is being tidally disrupted. A three-parameter King model yields a cluster radius of r_cl_=0.017{deg}+/-0.007{deg}, a core radius of r_c_=0.003{deg}+/-0.001{deg}, and a tidal radius of r_t_=0.04{deg}+/-0.02{deg}. A comparison of Padova and Dartmouth model-grids indicates that the cluster is not significantly {alpha}-enhanced, with a mean [Fe/H]=-0.55_-0.12_^+0.15^dex, and a population age of only 2.6+/-0.4Gyr. We rule out a statistically significant age spread at the main-sequence turnoff because of a narrow subgiant branch, and discuss the role of stellar rotation and cluster age, using Dartmouth and Geneva models: approximately 70% of the Seg 3 stars at or below the main-sequence turnoff have enhanced rotation. Our results for Segue 3 indicate that it is younger and more metal-rich than all previous studies have reported to date. From colors involving Washington C and SDSS-u filters, we identify several giants and a possible blue straggler for future follow-up spectroscopic studies, and we produce spectral energy distributions of previously known members and potential Segue 3 sources with Washington (CT_1_), Sloan (ugri), and VI-filters. Segue 3 shares the characteristics of unusual stellar systems that have likely been stripped from external dwarf galaxies as they are being accreted by the Milky Way, or that have been formed during such an event. Its youth, metallicity, and location are all inconsistent with Segue 3 being a cluster native to the Milky Way.
2324. 90 new SNIa from SDSS DR7
ID:
ivo://CDS.VizieR/J/MNRAS/430/1746
Title:
90 new SNIa from SDSS DR7
Short Name:
J/MNRAS/430/1746
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using a method to discover and classify supernovae (SNe) in galaxy spectra, we find 90 Type Ia SNe (SNe Ia) and 10 Type II SNe among the ~700000 galaxy spectra in the Sloan Digital Sky Survey Data Release 7 that have star-formation histories (SFHs) derived with the VErsatile SPectral Analysis code (VESPA). We use the SN Ia sample to measure SN Ia rates per unit stellar mass.
2325. New spectral types for Tycho2 stars
ID:
ivo://CDS.VizieR/J/PAZh/34/21
Title:
New spectral types for Tycho2 stars
Short Name:
J/PAZh/34/21
Date:
21 Oct 2021
Publisher:
CDS
Description:
We compare the spectroscopic and trigonometric parallaxes of common stars from the Tycho-2 Spectral Type and Hipparcos Catalogues. This comparison has revealed that the distance estimations for the overwhelming majority of stars by both methods yield very similar results. However, there is a small fraction of stars for which the distance estimates differences.
2326. 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.
2327. New times of maximum of CY Aqr
ID:
ivo://CDS.VizieR/J/other/JAD/16.2
Title:
New times of maximum of CY Aqr
Short Name:
J/other/JAD/16.2
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a collection of 102 new times of maximum of the SX Phoenicis star CY Aquarii. These times, together with 20 times of maximum taken from the literature, lead to a new local linear ephemeris for 2003-2009 with a formally slightly shorter period than the one for 1996-2002. It will require at least another half decade of additional monitoring before any significant update to any model can be considered. Such monitoring should preferably occur at regular intervals, be done in a consistent photometric band, and at high time resolution. A set of 114 new times of maximum obtained since 2002 leads to a new local linear ephemeris for 2003-2009: Tmax=2426159.512(+/-0.001)+0.061038349E(+/-0.000000002).
2328. New UBVRI color distribution in E galaxies
ID:
ivo://CDS.VizieR/J/A+A/383/30
Title:
New UBVRI color distribution in E galaxies
Short Name:
J/A+A/383/30
Date:
21 Oct 2021
Publisher:
CDS
Description:
Colour distributions have been obtained for 36 E and 4 SA0 galaxies of the northern Local Supercluster, observed in 2000/2001 at the 120cm telescope of Observatoire de Haute-Provence: field 11.6'x11.6'; scale 0.68"/pix. The radial profiles of the V magnitude and the colours U-B, B-V, V-R and V-I, were measured in greatly enlarged radial ranges, as compared to previous work, and with an improved accuracy. The colour system is the one of Cousins.
2329. 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.
2330. New ultracool subdwarfs
ID:
ivo://CDS.VizieR/J/A+A/598/A92
Title:
New ultracool subdwarfs
Short Name:
J/A+A/598/A92
Date:
21 Oct 2021
Publisher:
CDS
Description:
We developed an efficient method to search for late-type subdwarfs. We carried out a search cross-matching SDSS, 2MASS, and UKIDSS with VO tools. We considered different photometric and proper motion criteria for our selection. We identified 100 late-type subdwarf candidates. We obtained our own low-resolution optical spectra for 71 of our candidates and retrieved Sloan spectra for 30 of them (9 in common to the 71). We classified 92 candidates based on optical spectra. Our new discoveries include 49 subdwarfs, 25 extreme subdwarfs, six ultrasubdwarfs, one subdwarf/extreme subdwarf, and two dwarfs/subdwarfs. In addition, we discovered three early-L subdwarfs. We double the numbers of cool subdwarfs and derived a surface density of late-type subdwarfs.