- ID:
- ivo://CDS.VizieR/J/AJ/155/23
- Title:
- Low-mass fast rotators in the solar neighborhood
- Short Name:
- J/AJ/155/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The K2 mission is targeting large numbers of nearby (d<100 pc) GKM dwarfs selected from the SUPERBLINK proper motion survey ({mu}>40 mas/yr, V<20). Additionally, the mission is targeting low-mass, high proper motion stars associated with the local (d<500 pc) Galactic halo population also selected from SUPERBLINK. K2 campaigns 0 through 8 monitored a total of 26518 of these cool main-sequence stars. We used the auto-correlation function to search for fast rotators by identifying short-period photometric modulations in the K2 light curves. We identified 481 candidate fast rotators with rotation periods <4 days that show light-curve modulations consistent with starspots. Their kinematics show low average transverse velocities, suggesting that they are part of the young disk population. A subset (13) of the fast rotators is found among those targets with colors and kinematics consistent with the local Galactic halo population and may represent stars spun up by tidal interactions in close binary systems. We further demonstrate that the M dwarf fast rotators selected from the K2 light curves are significantly more likely to have UV excess and discuss the potential of the K2 mission to identify new nearby young GKM dwarfs on the basis of their fast rotation rates. Finally, we discuss the possible use of local halo stars as fiducial, non-variable sources in the Kepler fields.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/857/104
- Title:
- Low surface brightness galaxies from HSC-SSP
- Short Name:
- J/ApJ/857/104
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of extended low surface brightness galaxies (LSBGs) identified in the Wide layer of the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP). Using the first ~200deg^2^ of the survey, we have uncovered 781 LSBGs, spanning red (g-i>=0.64) and blue (g-i<0.64) colors and a wide range of morphologies. Since we focus on extended galaxies (r_eff_=2.5"-14"), our sample is likely dominated by low-redshift objects. We define LSBGs to have mean surface brightnesses \bar{mu}_eff_(g)>24.3mag/arcsec^2^, which allows nucleated galaxies into our sample. As a result, the central surface brightness distribution spans a wide range of {mu}_0_(g)=18-27.4mag/arcsec^2^, with 50% and 95% of galaxies fainter than 24.3 and 22mag/arcsec^2^, respectively. Furthermore, the surface brightness distribution is a strong function of color, with the red distribution being much broader and generally fainter than that of the blue LSBGs, and this trend shows a clear correlation with galaxy morphology. Red LSBGs typically have smooth light profiles that are well characterized by single-component Sersic functions. In contrast, blue LSBGs tend to have irregular morphologies and show evidence for ongoing star formation. We cross-match our sample with existing optical, HI, and ultraviolet catalogs to gain insight into the physical nature of the LSBGs. We find that our sample is diverse, ranging from dwarf spheroidals and ultradiffuse galaxies in nearby groups to gas-rich irregulars to giant LSB spirals, demonstrating the potential of the HSC-SSP to provide a truly unprecedented view of the LSBG population.
- ID:
- ivo://CDS.VizieR/J/ApJS/226/5
- Title:
- MACT survey. I. Opt. spectroscopy in Subaru Deep Field
- Short Name:
- J/ApJS/226/5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Deep rest-frame optical spectroscopy is critical for characterizing and understanding the physical conditions and properties of the ionized gas in galaxies. Here, we present a new spectroscopic survey called "Metal Abundances across Cosmic Time" or MACT, which will obtain rest-frame optical spectra for ~3000 emission-line galaxies. This paper describes the optical spectroscopy that has been conducted with MMT/Hectospec and Keck/DEIMOS for ~1900 z=0.1-1 emission-line galaxies selected from our narrowband and intermediate-band imaging in the Subaru Deep Field. In addition, we present a sample of 164 galaxies for which we have measured the weak [OIII]{lambda}4363 line (66 with at least 3{sigma} detections and 98 with significant upper limits). This nebular emission line determines the gas-phase metallicity by measuring the electron temperature of the ionized gas. This paper presents the optical spectra, emission-line measurements, interstellar properties (e.g., metallicity, gas density), and stellar properties (e.g., star formation rates, stellar mass). Paper II of the MACT survey (Ly et al. 2016ApJ...828...67L) presents the first results on the stellar mass-gas metallicity relation at z<=1 using the sample with [OIII]{lambda}4363 measurements.
- ID:
- ivo://CDS.VizieR/J/AJ/116/180
- Title:
- Magellanic clouds ultraviolet observations
- Short Name:
- J/AJ/116/180
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog is derived from wide-field far-ultraviolet (FUV; 1300-1800{AA}) images of the Large and Small Magellanic Clouds (LMC, SMC) obtained by the Ultraviolet Imaging Telescope (UIT) during the Astro-1 (1990 December 1-10) and Astro-2 (1995 March 2-18) missions. The FUV magnitudes are derived from point-spread function photometry for 37,333 stars in the LMC (the UIT FUV magnitudes for 11,306 stars in the SMC were presented by Cornett et al. (1997AJ....113.1011C), with a completeness limit of m_UV_ ~ 15mag and a detection limit of m_UV_ ~ 17.5. The average uncertainty in the photometry is ~ 0.1mag.
105. MaNGA catalog, DR15
- ID:
- ivo://CDS.VizieR/J/AJ/154/86
- Title:
- MaNGA catalog, DR15
- Short Name:
- J/AJ/154/86
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the sample design for the SDSS-IV MaNGA survey and present the final properties of the main samples along with important considerations for using these samples for science. Our target selection criteria were developed while simultaneously optimizing the size distribution of the MaNGA integral field units (IFUs), the IFU allocation strategy, and the target density to produce a survey defined in terms of maximizing signal-to-noise ratio, spatial resolution, and sample size. Our selection strategy makes use of redshift limits that only depend on i-band absolute magnitude (M_i_), or, for a small subset of our sample, M i and color (NUV-i). Such a strategy ensures that all galaxies span the same range in angular size irrespective of luminosity and are therefore covered evenly by the adopted range of IFU sizes. We define three samples: the Primary and Secondary samples are selected to have a flat number density with respect to M_i_ and are targeted to have spectroscopic coverage to 1.5 and 2.5 effective radii (Re), respectively. The Color-Enhanced supplement increases the number of galaxies in the low-density regions of color-magnitude space by extending the redshift limits of the Primary sample in the appropriate color bins. The samples cover the stellar mass range 5x10^8^<=M*<=3x10^11^M_{sun}/h^2^ and are sampled at median physical resolutions of 1.37 and 2.5kpc for the Primary and Secondary samples, respectively. We provide weights that will statistically correct for our luminosity and color-dependent selection function and IFU allocation strategy, thus correcting the observed sample to a volume-limited sample.
- ID:
- ivo://CDS.VizieR/J/ApJS/237/36
- Title:
- Merging dwarf galaxies in the local universe
- Short Name:
- J/ApJS/237/36
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the largest publicly available catalog of interacting dwarf galaxies. It includes 177 nearby merging dwarf galaxies of stellar mass M*<10^10^M_{sun}_ and redshifts z<0.02. These galaxies are selected by visual inspection of publicly available archival imaging from two wide-field optical surveys (SDSS-III and the Legacy Survey), and they possess low-surface-brightness features that are likely the result of an interaction between dwarf galaxies. We list UV and optical photometric data that we use to estimate stellar masses and star formation rates. So far, the study of interacting dwarf galaxies has largely been done on an individual basis, and lacks a sufficiently large catalog to give statistics on the properties of interacting dwarf galaxies, and their role in the evolution of low-mass galaxies. We expect that this public catalog can be used as a reference sample to investigate the effects of the tidal interaction on the evolution of star formation, and the morphology/structure of dwarf galaxies. Our sample is overwhelmingly dominated by star-forming galaxies, and they are generally found significantly below the red sequence in the color-magnitude relation. The number of early-type galaxies is only 3 out of 177. We classify them, according to observed low-surface-brightness features, into various categories including shells, stellar streams, loops, antennae, or simply interacting. We find that dwarf-dwarf interactions tend to prefer the low-density environment. Only 41 out of the 177 candidate dwarf-dwarf interaction systems have giant neighbors within a sky-projected distance of 700kpc and a line-of-sight radial velocity range +/-700km/s, and compared to the LMC-SMC, they are generally located at much larger sky-projected distances from their nearest giant neighbors.
- ID:
- ivo://CDS.VizieR/J/MNRAS/450/3811
- Title:
- M33 GALEX catalogue of UV point sources
- Short Name:
- J/MNRAS/450/3811
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The hottest stars (>10000K), and by extension typically the most massive ones, are those that will be prevalent in the ultraviolet (UV) portion of the electromagnetic spectrum, and we expect to numerous B, O and WR (WR) stars to be bright in UV data. In this paper, we update the previous point source UV catalogue of M33, created using the Ultraviolet Imaging Telescope (UIT), using data from the Galaxy Evolution Explorer (GALEX). We utilize point spread function photometry to optimally photometer sources in the crowded regions of the galaxy, and benefit from GALEX's increased sensitivity compared to UIT. We match our detections with data from the Local Group Galaxies Survey to create a catalogue with photometry spanning from the far-UV through the optical for a final list of 24738 sources. All of these sources have far-UV (FUV; 1516{AA}), near-UV (NUV; 2267{AA}) and V data, and a significant fraction also have U, B, R and I data as well. We also present an additional 3000 sources that have no matching optical counterpart. We compare all of our sources to a catalogue of known WR stars in M33 and find that we recover 114 of 206 stars with spatially-coincident UV point sources. Additionally, we highlight and investigate those sources with unique colours as well as a selection of other well-studied sources in M33.
- ID:
- ivo://CDS.VizieR/II/269
- Title:
- MSX Ultraviolet Point Source Catalog
- Short Name:
- II/269
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Midcourse Space Experiment (MSX) Ultraviolet Point Source Catalog contains 47,283 point sources from a set of 201 observations that surveyed approximately half the sky and from a set of 32 pointed observations toward specific targets. For each source, we provide position, UV magnitude and uncertainty in at least one of six filters and where possible an identification of a nearby source from the SIMBAD database. If a nearby source is identified, we include its proximity to the MSX source, and if known, the spectral type and the B and V magnitudes of the SIMBAD object. There were 11,565 matches between MSX and SIMBAD objects, and we estimate false identification to be about 3%. The limiting fluxes differ from filter to filter, and range from 10^-16^erg/s/cm2/{AA} for IUN4 to 7.8*10^-12^erg/s/cm2/{AA} for IUW3. Because of variations among the observation sets, the catalog is not complete to the limiting magnitudes for the filters. The UV instrument on MSX was named UVISI (Mill et al., 1994, Journal of Spacecraft and Rockets, 31, 900 (1994JSpRo..31..900M in ADS); Carbary et al., 1994, Applied Optics, 33, 4201 (1994ApOpt..33.4201C in ADS)). The fields-of-view for the narrow-field and wide-field UV imagers were 1.46x1.19deg (detector pixels of 20.6"x17.5") and 13.4x9.2deg (detector pixels of 3.12'x2.27'), respectively. Four filters were used with the narrow-field imager (IUN) with effective wavelengths centered at 2480{AA} (IUN3), 2310{AA} (IUN4), 2230{AA} (IUN5), and 2930{AA} (IUN6). Two filters were used with the wide-field imager (IUW) and centered at 1320{AA} (IUW3) and 1560{AA} (IUW6). Two data files are available for the MSX UV Point Source Catalog: the calibration data file and the catalog data file.
- ID:
- ivo://CDS.VizieR/J/AJ/121/3048
- Title:
- Multicolor photometry in NGC 1512 and NGC 5248
- Short Name:
- J/AJ/121/3048
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present broadband (U, V, I, and H) and narrowband (H{alpha}+[N II] and Pa{alpha}) images of the circumnuclear starburst rings in two nearby spiral galaxies, NGC 1512 and NGC 5248, obtained with the WFPC2 and NICMOS cameras on HST. Combined with previously published ultraviolet (UV) HST images at 2300{AA} these data provide a particularly wide wavelength range with which to study the properties of the stellar populations, the gas, and the dust in the rings.
- ID:
- ivo://CDS.VizieR/J/AJ/144/191
- Title:
- Multicolor photometry of 135 star clusters in M31
- Short Name:
- J/AJ/144/191
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present photometry for young star clusters in M31, which are selected from Caldwell et al. These star clusters have been observed as part of the Beijing-Arizona-Taiwan-Connecticut (BATC) Multicolor Sky Survey from 1995 February to 2008 March. The BATC images including these star clusters are taken with 15 intermediate-band filters covering 3000-10000{AA}. Combined with photometry in the GALEX far- and near-ultraviolet, broadband UBV RI, SDSS ugriz, and infrared JHK_s_ of Two Micron All Sky Survey, we obtain their accurate spectral energy distributions (SEDs) from 1538 to 20000{AA}. We derive these star clusters' ages and masses by comparing their SEDs with stellar population synthesis models. Our results are in good agreement with previous determinations. The mean value of age and mass of young clusters (<2Gyr) is about 385Myr and 2x10^4^M_{sun}_, respectively. There are two distinct peaks in the age distribution, a highest peak at age ~60Myr and a secondary peak around 250Myr, while the mass distribution shows a single peak around 10^4^M_{sun}_. A few young star clusters have two-body relaxation times greater than their ages, indicating that those clusters have not been well dynamically relaxed and therefore have not established the thermal equilibrium. There are several regions showing aggregations of young star clusters around the 10kpc ring and the outer ring, indicating that the distribution of the young star clusters is well correlated with M31's star-forming regions. The young massive star clusters (age<=100Myr and mass>=10^4^M_{sun}_) show apparent concentration around the ring splitting region, suggesting a recent passage of a satellite galaxy (M32) through M31 disk.