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- ID:
- ivo://CDS.VizieR/J/AJ/161/231
- Title:
- A list of ~330000 stars Kepler missed
- Short Name:
- J/AJ/161/231
- Date:
- 09 Mar 2022 22:00:00
- Publisher:
- CDS
- Description:
- The Kepler Mission revolutionized exoplanet science and stellar astrophysics by obtaining highly precise photometry of over 200000 stars over 4yr. A critical piece of information to exploit Kepler data is its selection function, since all targets had to be selected from a sample of half a million stars on the Kepler CCDs using limited information. Here we use Gaia DR2 to reconstruct the Kepler selection function and explore possible biases with respect to evolutionary state, stellar multiplicity, and kinematics. We find that the Kepler target selection is nearly complete for stars brighter than Kp<14mag and was effective at selecting main-sequence stars, with the fraction of observed stars decreasing from 95% to 60% between 14<Kp<16mag. We find that the observed fraction for subgiant stars is only 10% lower, confirming that a significant number of subgiants selected for observation were believed to be main-sequence stars. Conversely we find a strong selection bias against low-luminosity red giant stars (R~3-5R_{sun}_, Teff~5500K), dropping from 90% at Kp=14mag to below 30% at Kp=16mag, confirming that the target selection was efficient at distinguishing dwarfs from giants. We compare the Gaia Re-normalized Unit Weight Error (RUWE) values of the observed and nonobserved main-sequence stars and find a difference in elevated (>1.2) RUWE values at ~{sigma} significance, suggesting that the Kepler target selection shows some bias against either close or wide binaries. We furthermore use the Gaia proper motions to show that the Kepler selection function was unbiased with respect to kinematics.
- ID:
- ivo://CDS.VizieR/V/17A
- Title:
- A list of Supergiant Stars
- Short Name:
- V/17A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue is a compilation of about 5000 stars classified as supergiants (class I or II) in the literature. The following information is given: DM and HD identifications, coordinates, photometry, radial velocity and MK classification
- ID:
- ivo://CDS.VizieR/J/AZh/92/834
- Title:
- A list of tantalum lines
- Short Name:
- J/AZh/92/834
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The list contains wavelengths of spectral lines of neutral and single ionized tantalum for accurate calibration of the Hamilton echelle spectrograph installed at the Shane 3-m telescope of the Lick observatory that was in operation before June 9, 2011 (S&J Box, Westinghouse WL23418, symbol ThAr02). Furthermore, the list may be used for wavelength calibration of another Lick lamp (symbol ThAr07, Westinghouse Box, Westinghouse WL32809) that was in operation from February 17, 1995 to June 19, 2011.
- ID:
- ivo://nasa.heasarc/pigssboofd
- Title:
- Allen Telescope Array Pi GHz Sky Survey (PiGSS) Boo Field Source Catalog
- Short Name:
- PIGSSBOOFD
- Date:
- 14 Feb 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Pi GHz Sky Survey (PiGSS) is a key project of the Allen Telescope Array (ATA). PiGSS is a 3.1 GHz survey of radio continuum emission in the extragalactic sky with an emphasis on synoptic observations that measure the static and time-variable properties of the sky. During the 2.5 year campaign, PiGSS will twice observe ~250,000 radio sources in the 10,000 deg<sup>2</sup> region of the sky with b > 30 degrees to an rms sensitivity of ~1 mJy. Additionally, sub-regions of the sky will be observed multiple times to characterize variability on timescales of days to years. Presented here are the results from observations of a 10 deg<sup>2</sup> region in the Bootes constellation overlapping the NOAO Deep Wide Field Survey field. The PiGSS image was constructed from 75 daily observations distributed over a 4 month period and has an rms flux density between 200 and 250 µJy. This represents a deeper image by a factor of 4-8 than the authors will achieve over the entire 10,000 deg<sup>2</sup>. In this table, they provide flux densities, source sizes, and spectral indices for the 425 sources detected in the image. They identify ~100 new flat-spectrum radio sources, and project that, when completed, PiGSS will identify 104 flat-spectrum sources. In their paper the authors identify one source that is a possible transient radio source. This survey provides new limits on faint radio transients and variables with characteristic durations of months. This table was created by the HEASARC in March 2011 based on electronic versions of Tables 2 and 4 from the reference paper which were obtained from the ApJ web site. The HEASARC changed the sign of the values of the last parameter in Table 4 (herein called spectral_index_3_error) from negative to positive. In March 2013, after receiving a clarification from Steve Croft, the HEASARC corrected the names of the 4 parameters describing the source sizes (to reflect the fact that they were diameters nor radii) to major_axis, minor_axis, fit_major_axis and fit_minor_axis. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/pigsselcnf
- Title:
- Allen Telescope Array Pi GHz Sky Survey (PiGSS) Deep Fields Source Catalog
- Short Name:
- PIGSSELCNF
- Date:
- 14 Feb 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains results from a total of 459 repeated 3.1-GHz radio continuum observations (of which 379 were used in a search for transient sources) of the ELAIS-N1, Coma, Lockman Hole, and NOAO Deep Wide Field Survey (NDWFS) fields as part of the Allen Telescope Array (ATA) Pi GHz Sky Survey (PiGSS). The observations were taken in 2 simultaneous 100-MHz wide bands centered at 3.04 and 3.14 GHz approximately once per day between 2009 May and 2011 April. Each image covers 11.8 square degrees and has 100" FWHM resolution. Deep images for each of the four fields have rms noise between 180 and 310 µJy (µJy), and the corresponding catalogs contain ~200 sources in each field. Typically 40-50 of these sources are detected in each single-epoch image. This represents one of the shortest cadence, largest area, multi-epoch surveys undertaken at these frequencies. The authors compared the catalogs generated from the combined images to those from individual epochs, and from monthly averages, as well as to legacy surveys. They undertook a search for transients, with particular emphasis on excluding false positive sources,but find no confirmed transients, defined here as sources that can be shown to have varied by at least a factor of 10. However, the authors found one source that brightened in a single-epoch image to at least six times the upper limit from the corresponding deep image. They also found a source associated with a z = 0.6 quasar which appears to have brightened by a factor ~3 in one of their deep images, when compared to catalogs from legacy surveys. The authors place new upper limits on the number of transients brighter than 10 mJy: fewer than 0.08 transients deg<sup>-2</sup> with characteristic timescales of months to years; fewer than 0.02 deg<sup>-2</sup> with timescales of months; and fewer than 0.009 deg<sup>-2</sup> with timescales of days. In this study, the authors accepted only as real sources those that are independently detected in both frequencies in at least one epoch (with a position matching tolerance of 50", corresponding to a false match probability of <2%). Their threshold of ~ 4.2 sigma for detection in a single image corresponds to a threshold of ~ 5.9 sigma in the dual-image catalog. They generated catalogs for the deep fields, consisting only of sources detected at both frequencies, and these are contained in the present HEASARC table. Notice that the authors previously published a list of 425 radio sources in the NDWFS field in the constellation of Bootes in an earlier paper (Bower et al 2010, ApJ, 725, 1792, available as the HEASARC database table PIGSSBOOFD). In the 2013 paper, they have performed a partial re-analysis of these data to conform with the updated analysis techniques used on the other three fields. This table was created by the HEASARC in March 2013 based on electronic versions of Tables 2, 3, 4 and 5 (source lists for each of the 4 fields, ELAIS N1, Lockman, Coma, and NDWFS, respectively) from the reference paper which were obtained from the ApJ web site. The HEASARC has created a new parameter called field_name which identifies in which table/field the source can be found. Thus, to select only sources in the Lockman Hole field, the user should select field_name= 'Lockman'. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/atats
- Title:
- Allen Telescope Array Twenty-cm Survey (ATATS) Source Catalog
- Short Name:
- ATATS
- Date:
- 14 Feb 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the source catalog from the Allen Telescope Array Twenty-centimeter Survey (ATATS), a multi-epoch (12 visits), 690 deg<sup>2</sup> radio image and catalog at 1.4 GHz. The survey is designed to detect rare, very bright transients as well as to verify the capabilities of the ATA to form large mosaics. The combined image using data from all 12 ATATS epochs has an rms noise sigma = 3.94 mJy beam<sup>-1</sup> and a dynamic range of 180, with a circular beam of 150 arcseconds FWHM. It contains 4408 sources to a limiting sensitivity of 5 sigma = 20 mJy beam<sup>-1</sup>. The authors compare the catalog generated from this 12-epoch combined image to the NRAO VLA Sky Survey (NVSS), a legacy survey at the same frequency, and find that they can measure source positions to better than ~ 20 arcseconds. For sources above the ATATS completeness limit, the median flux density is 97% of the median value for matched NVSS sources, indicative of an accurate overall flux calibration. The authors examine the effects of source confusion due to the effects of differing resolution between the ATATS and NVSS on their ability to compare flux densities. They detect no transients at flux densities greater than 40 mJy in comparison with NVSS and place a 2 sigma upper limit of 0.004 deg<sup>-2</sup> on the transient rate for such sources. These results suggest that the >~ 1 Jy transients reported by Matsumara et al. (2009, AJ, 138, 787) may not be true transients, but rather variable sources at their flux density threshold. This table was created by the HEASARC in September 2010 based on the electronic version of Table 2 from the reference paper which was obtained from the ApJ web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://CDS.VizieR/J/ApJ/742/112
- Title:
- All quiescent magnitudes for CI Aql and U Sco
- Short Name:
- J/ApJ/742/112
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- I report on the cumulative results from a program started 24 years ago designed to measure the orbital period change of recurrent novae (RNe) across an eruption. The goal is to use the orbital period change to measure the mass ejected during each eruption as the key part of trying to measure whether the RNe white dwarfs are gaining or losing mass over an entire eruption cycle, and hence whether they can be progenitors for Type Ia supernovae. This program has now been completed for two eclipsing RNe: CI Aquilae (CI Aql) across its eruption in 2000 and U Scorpii (U Sco) across its eruption in 1999. For CI Aql, I present 78 eclipse times from 1991 to 2009 (including four during the tail of the 2000 eruption) plus two eclipses from 1926 and 1935. For U Sco, I present 67 eclipse times, including 46 times during quiescence from 1989 to 2009, plus 21 eclipse times in the tails of the 1945, 1999, and 2010 eruptions. The eclipse times during the tails of eruptions are systematically and substantially shifted with respect to the ephemerides from the eclipses in quiescence, with this being caused by shifts of the center of light during the eruption. These eclipse times are plotted on an O-C diagram and fitted to models with a steady period change (dP/dt) between eruptions (caused by, for example, conservative mass transfer) plus an abrupt period change ({Delta}P) at the time of eruption. The primary uncertainty arises from the correlation between {Delta}P with dP/dt, such that a more negative dP/dt makes for a more positive {Delta}P. For CI Aql, the best fit is {Delta}P=-3.7^+9.2^_-7.3_x10^-7^. For U Sco, the best fit is {Delta}P=(+43+/-69)x10^-7^ days. These period changes can directly give a dynamical measure of the mass ejected (M_ejecta_) during each eruption with negligible sensitivity to the stellar masses and no uncertainty from distances. For CI Aql, the 1{sigma} upper limit is M_ejecta_<10x10^-7^ M_{sun}_. For U Sco, I derive M_ejecta_=(43+/-67)x10^-7^ M_{sun}_.
- ID:
- ivo://CDS.VizieR/J/AcA/50/177
- Title:
- All Sky Automated Survey Catalog
- Short Name:
- J/AcA/50/177
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results of the first two years of observations using the All Sky Automated Survey prototype camera are presented. More than 140000 stars in 50 Selected Fields covering 300 square degrees were monitored each clear night in the I-band resulting in the ASAS Photometric I-band Catalog containing over 5*10^7^ individual measurements. Nightly monitoring of over 100 standard stars confirms that most of our data remains within {sigma}_I_=0.03mag of the standard I system. Search for the stars varying on the time scales longer than a day revealed about 3800 variable stars (mostly irregular, pulsating and binaries) brighter than 13mag. Only 630 of them are known or suspected variables included in the GCVS (Kholopov 1985, Cat. <II/214>). Among the stars brighter than I~7.5 (which are saturated on our frames) we have found about 50 variables (12 are in the GCVS, 6 others in the Hipparcos catalog (Cat. <I/239>). Because of the large volume of data we present here only selected tables and light curves, but the complete ASAS Catalog of Variable Stars (currently divided into Periodic and Miscellaneous sections) and all photometric data are available on the Internet http://www.astrouw.edu.pl/~gp/asas/asas.html or http://archive.princeton.edu/~asas/
- ID:
- ivo://CDS.VizieR/J/AcA/48/35
- Title:
- All Sky Automated Survey variable stars
- Short Name:
- J/AcA/48/35
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results of the first two months of observations using the All Sky Survey prototype camera are presented. More than 45000 stars in 24 Selected Fields covering 140 square degrees were monitored a few times per night resulting in the I-band catalog containing 10^7^ individual measurements. Period search revealed 126 variable stars brighter than 13mag with periods less than 20d. Only 30 of them are known variable stars included in the General Catalogue of Variable Stars (<II/214>). The other 90 objects are newly detected variable stars - mainly eclipsing binaries (75%) and pulsating stars (17%). We estimate that completeness of the current catalogs of variable stars is smaller than 50% already for the stars brighter than 9mag. The catalog is accessible over the WWW: http://www.astrouw.edu.pl/~gp/asas/asas.html
