- ID:
- ivo://CDS.VizieR/J/ApJ/833/281
- Title:
- Candidate rotating M dwarfs from PS1-MDS
- Short Name:
- J/ApJ/833/281
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on an ongoing project to investigate activity in the M dwarf stellar population observed by the Pan-STARRS1 Medium-Deep Survey (PS1-MDS). Using a custom-built pipeline, we refine an initial sample of ~4 million sources in PS1-MDS to a sample of 184148 candidate cool stars using color cuts. Motivated by the well-known relationship between rotation and stellar activity, we use a multiband periodogram analysis and visual vetting to identify 270 sources that are likely rotating M dwarfs. We derive a new set of polynomials relating M dwarf PS1 colors to fundamental stellar parameters and use them to estimate the masses, distances, effective temperatures, and bolometric luminosities of our sample. We present a catalog containing these values, our measured rotation periods, and cross-matches to other surveys. Our final sample spans periods of <~1-130 days in stars with estimated effective temperatures of ~2700-4000K. Twenty-two of our sources have X-ray cross-matches, and they are found to be relatively X-ray bright as would be expected from selection effects. Our data set provides evidence that Kepler-based searches have not been sensitive to very slowly rotating stars (P_rot_>~70 day), implying that the observed emergence of very slow rotators in studies of low-mass stars may be a systematic effect. We also see a lack of low-amplitude (<2%) variability in objects with intermediate (10-40 day) rotation periods, which, considered in conjunction with other observational results, may be a signpost of a loss of magnetic complexity associated with a phase of rapid spin-down in intermediate-age M dwarfs. This work represents just a first step in exploring stellar variability in data from the PS1-MDS and, in the farther future, Large Synoptic Survey Telescope.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/158/77
- Title:
- Candidates and members of the Pisces-Eridanus stream
- Short Name:
- J/AJ/158/77
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Pisces-Eridanus (Psc-Eri), a nearby (d~80-226 pc) stellar stream stretching across ~120{deg} of the sky, was recently discovered with Gaia data. The stream was claimed to be ~1 Gyr old, which would make it an exceptional discovery for stellar astrophysics, as star clusters of that age are rare and tend to be distant, limiting their utility as benchmark samples. We test this old age for Psc-Eri in two ways. First, we compare the rotation periods for 101 low-mass members (measured using time-series photometry from the Transiting Exoplanet Survey Satellite) to those of well-studied open clusters. Second, we identify 34 new high-mass candidate members, including the notable stars {lambda} Tauri (an Algol-type eclipsing binary) and HD 1160 (host to a directly imaged object near the hydrogen-burning limit). We conduct an isochronal analysis of the color-magnitude data for these highest-mass members, again comparing our results to those for open clusters. Both analyses show that the stream has an age consistent with that of the Pleiades, i.e., ~120 Myr. This makes the Psc-Eri stream an exciting source of young benchmarkable stars and, potentially, exoplanets located in a more diffuse environment that is distinct from that of the Pleiades and of other dense star clusters.
- ID:
- ivo://CDS.VizieR/J/ApJ/872/199
- Title:
- Candidate spectrophotometric standard DA WDs
- Short Name:
- J/ApJ/872/199
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present precise photometry and spectroscopy for 23 candidate spectrophotometric standard white dwarfs. The selected stars are distributed in the Northern hemisphere and around the celestial equator, and are all fainter than r~16.5mag. This network of stars, when established as standards and together with the three Hubble Space Telescope primary CALSPEC white dwarfs, will provide a set of spectrophotometric standards to directly calibrate data products to better than 1%. In future deep photometric surveys and facilities, these new faint standard white dwarfs will have enough signal-to-noise ratio to be measured accurately while still avoiding saturation. They will also fall within the dynamic range of large telescopes and their instruments for the foreseeable future. This paper discusses the provenance of the observational data for our candidate standard stars.
- ID:
- ivo://CDS.VizieR/J/MNRAS/413/1581
- Title:
- Candidate subdwarfs and white dwarfs
- Short Name:
- J/MNRAS/413/1581
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometry from the Two-Micron All-Sky Survey (2MASS), United States Naval Observatory CCD Astrograph Catalog (UCAC3) and SuperCosmos catalogues, together with proper motions from the Tycho-2, Kharkiv Proper Motions (XPM) and UCAC3 catalogues, is used to select all-sky samples of 28 candidate white dwarfs, 1826 evolved and 7641 unevolved subdwarfs for R from 9-17mag. The samples are separated from main-sequence stars with an admixture of less than 10 per cent, owing to an analysis of the distribution of the stars in colour index versus reduced proper-motion diagrams for various latitudes using related Monte Carlo simulations. It is shown that the XPM and UCAC3 catalogues have the same level of proper-motion accuracy. Most of the selected stars have at least six-band photometry. This allows us to eliminate some admixtures and reveal some binaries. Empirical calibrations of absolute magnitude versus colour index and reduced proper motion for Hipparcos stars give us distances and a three-dimensional (3D) distribution for all the selected stars. It is shown that the subdwarf samples are almost complete for the Tycho-2 stars, i.e. to 11mag or 150pc from the Sun. For fainter stars from the XPM and UCAC3 catalogues, the subdwarf samples are complete only to 20-60 per cent because of the selection method and incompleteness of the catalogues.
- ID:
- ivo://CDS.VizieR/J/MNRAS/453/2653
- Title:
- Carbon stars in the Galaxy and its satellites
- Short Name:
- J/MNRAS/453/2653
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We assemble 121 spectroscopically confirmed halo carbon stars, drawn from the literature, exhibiting measurable variability in the Catalina Surveys. We present their periods and amplitudes, which are used to estimate distances from period-luminosity relationships. The location of the carbon stars - and their velocities when available - allow us to trace the streams of the Sagittarius (Sgr) dwarf spheroidal galaxy. These are compared to a canonical numerical simulation of the accretion of Sgr. We find that the data match this model well for heliocentric distances of 15-50kpc, except for a virtual lack of carbon stars in the trailing arm just north of the Galactic plane, and there is only tentative evidence of the leading arm south of the plane. The majority of the sample can be attributed to the Sgr accretion. We also find groups of carbon stars which are not part of Sgr; most of which are associated with known halo substructures. A few have no obvious attribution and may indicate new substructure. We find evidence that there may be a structure behind the Sgr leading stream apocentre, at ~100kpc, and a more distant extension to the Pisces Overdensity also at ~100kpc. We study a further 75 carbon stars for which no good period data could be obtained, and for which NIR magnitudes and colours are used to estimate distances. These data add support for the features found at distances beyond 100kpc.
- ID:
- ivo://CDS.VizieR/J/AcA/64/359
- Title:
- Catalog of binary UV Ceti stars
- Short Name:
- J/AcA/64/359
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A catalogue of nearby UV Ceti type flare stars in (137) visual binary systems is presented in the form of two separate tables of information. The catalogue has developed from Catalogue and Bibliography of UV Cet stars (Gershberg et al., 1999, Cat. J/A+AS/139/555) and the list of nearby flare stars (Pettersen, 1991MmSAI..62..217P) by including more recent and additional information from catalogues of binary stars (WDS, Mason et al., 2001-2014, Cat. B/wds; ORB6, Hartkopf et al. 2006-2014; DM3, Mason+ 2006-2014) and data from the Catalog of Nearby Stars, Preliminary 3rd Version (Gliese et al., 1991, Cat. V/70), from Hipparcos, the New Reduction (van Leeuwen 2007, Cat. I/311) and from SIMBAD. Some issues relating to the mass, luminosity and spectrum relations of flare stars are also discussed.
- ID:
- ivo://CDS.VizieR/J/ApJ/786/29
- Title:
- Catalog of distances to molecular clouds
- Short Name:
- J/ApJ/786/29
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Distance measurements to molecular clouds are important but are often made separately for each cloud of interest, employing very different data and techniques. We present a large, homogeneous catalog of distances to molecular clouds, most of which are of unprecedented accuracy. We determine distances using optical photometry of stars along lines of sight toward these clouds, obtained from PanSTARRS-1. We simultaneously infer the reddenings and distances to these stars, tracking the full probability distribution function using a technique presented in Green et al. (2014ApJ...783..114G). We fit these star-by-star measurements using a simple dust screen model to find the distance to each cloud. We thus estimate the distances to almost all of the clouds in the Magnani et al. (1985ApJ...295..402M, MBM) catalog, as well as many other well-studied clouds, including Orion, Perseus, Taurus, Cepheus, Polaris, California, and Monoceros R2, avoiding only the inner Galaxy. Typical statistical uncertainties in the distances are 5%, though the systematic uncertainty stemming from the quality of our stellar models is about 10%. The resulting catalog is the largest catalog of accurate, directly measured distances to molecular clouds. Our distance estimates are generally consistent with available distance estimates from the literature, though in some cases the literature estimates are off by a factor of more than two.
- ID:
- ivo://CDS.VizieR/J/AJ/151/59
- Title:
- Catalog of Earth-Like Exoplanet Survey Targets
- Short Name:
- J/AJ/151/59
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Locating planets in circumstellar habitable zones (HZs) is a priority for many exoplanet surveys. Space-based and ground-based surveys alike require robust toolsets to aid in target selection and mission planning. We present the Catalog of Earth-Like Exoplanet Survey Targets (CELESTA), a database of HZs around 37000 nearby stars. We calculated stellar parameters, including effective temperatures, masses, and radii, and we quantified the orbital distances and periods corresponding to the circumstellar HZs. We gauged the accuracy of our predictions by contrasting CELESTA's computed parameters to observational data. We ascertain a potential return on investment by computing the number of HZs probed for a given survey duration. A versatile framework for extending the functionality of CELESTA into the future enables ongoing comparisons to new observations, and recalculations when updates to HZ models, stellar temperatures, or parallax data become available. We expect to upgrade and expand CELESTA using data from the Gaia mission as the data become available.
- ID:
- ivo://CDS.VizieR/J/ApJS/234/1
- Title:
- Catalog of M, L, & T dwarfs from PS1 3{pi} Survey
- Short Name:
- J/ApJS/234/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 9888 M, L and T dwarfs detected in the Pan-STARRS1 3{pi} Survey (PS1), covering three-quarters of the sky. Our catalog contains nearly all known objects of spectral types L0-T2 in the PS1 field, with objects as early as M0 and as late as T9, and includes PS1, 2MASS, AllWISE, and Gaia DR1 photometry. We analyze the different types of photometry reported by PS1 and use two types in our catalog in order to maximize both depth and accuracy. Using parallaxes from the literature, we construct empirical SEDs for field ultracool dwarfs spanning 0.5-12{mu}m. We determine typical colors of M0-T9 dwarfs and highlight the distinctive colors of subdwarfs and young objects. We combine astrometry from PS1, 2MASS, and Gaia DR1 to calculate new proper motions for our catalog. We achieve a median precision of 2.9mas/yr, a factor of ~3-10 improvement over previous large catalogs. Our catalog contains proper motions for 2405 M6-T9 dwarfs and includes the largest set of homogeneous proper motions for L and T dwarfs published to date, 406 objects for which there were no previous measurements, and 1176 objects for which we improve upon previous literature values. We analyze the kinematics of ultracool dwarfs in our catalog and find evidence that bluer but otherwise generic late-M and L field dwarfs (i.e., not subdwarfs) tend to have tangential velocities higher than those of typical field objects. With the public release of the PS1 data, this survey will continue to be an essential tool for characterizing the ultracool dwarf population.
- ID:
- ivo://CDS.VizieR/J/AJ/141/21
- Title:
- CCD distance estimates of SCR targets
- Short Name:
- J/AJ/141/21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present CCD photometric distance estimates of 100 SCR (SuperCOSMOS RECONS) systems with {mu}>=0.18"/yr, 29 of which are new discoveries previously unpublished in this series of papers. These distances are estimated using a combination of new VRI photometry acquired at CTIO and JHK magnitudes extracted from 2MASS. The estimates are improvements over those determined using photographic plate BRI magnitudes from SuperCOSMOS plus JHK, as presented in the original discovery papers. In total, 77 of the 100 systems investigated are predicted to be within 25pc.
