- ID:
- ivo://CDS.VizieR/J/ApJS/241/35
- Title:
- Period-luminosity relations of RSGs in M33 & M31
- Short Name:
- J/ApJS/241/35
- Date:
- 11 Mar 2022
- Publisher:
- CDS
- Description:
- Based on previously selected preliminary samples of red supergiants (RSGs) in M33 and M31, the foreground stars and luminous asymptotic giant branch stars are further excluded, which leads to the samples of 717 RSGs in M33 and 420 RSGs in M31. With the time-series data from the Intermediate Palomar Transient Factory survey spanning nearly 2000 days, the period and amplitude of RSGs are analyzed. According to the light-curve characteristics, they are classified into four categories in which 84 and 56 objects in M33 and M31, respectively, are semi-regular variables. For these semi-regular variables, the pulsation mode is identified by comparing with the theoretical model, which yielded 19 (7) sources in the first overtone mode in M33 (M31), and the other 65 (49) RSGs in M33 (M31) in the fundamental mode. The period-luminosity (P-L) relation is analyzed for the RSGs in the fundamental mode. The P-L relation is found to be tight in the infrared, i.e., the Two Mircon All-Sky Survey (2MASS) JHK_S_ bands and the short-wavelength bands of Spitzer. Meanwhile, the inhomogeneous extinction causes the P-L relation scattering in the V band, and the dust emission causes the less tight P-L relation in the Spitzer/[8.0] and [24] bands. The derived P-L relations in the 2MASS/K_S_ band are in agreement with those of RSGs in the Small Magellanic Cloud, the Large Magellanic Cloud, and the Milky Way within the uncertainty range. It is found that the number ratio of RSGs pulsating in the fundamental mode to the first overtone mode increases with metallicity.
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- ID:
- ivo://CDS.VizieR/III/150A
- Title:
- Perkins Revised MK Types for the Cooler Stars
- Short Name:
- III/150A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The original catalog of standard stars classified on the Revised MK system published in 1989 contains 1054 standard stars of spectral types G0 and later (G, K, M, and a few S stars) classified at the Perkins Observatory. The present version of the catalog takes into account the revisions (before 14h of RA) presented by Philip C. Keenan and Gerald H. Newsom at the Department of Astronomy of the Ohio State University (http://www-astronomy.mps.ohio-state.edu/MKCool) dated 2000 January; the Sun (G2V star) has been omitted from the catalog. Accurate positions were added in 2003. The revised MK system is described by Keenan (1987PASP...99..713K). The spectrograms used for the classification were taken at four different observatories; hence, extensive comparisons have been made to ensure consistency between the Northern and Southern Hemispheres. The list provides a consistent set of standards in most parts of the sky and over a considerable range in magnitude, for stars later than G0. The catalog is not a survey complete to any magnitude and is not intended for statistical studies.
- ID:
- ivo://CDS.VizieR/J/MNRAS/466/2006
- Title:
- Phoenix dwarf galaxy RV and [Fe/H] catalog
- Short Name:
- J/MNRAS/466/2006
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Transition type dwarf galaxies are thought to be systems undergoing the process of transformation from a star-forming into a passively evolving dwarf, which makes them particularly suitable to study evolutionary processes driving the existence of different dwarf morphological types. Here we present results from a spectroscopic survey of ~200 individual red giant branch stars in the Phoenix dwarf, the closest transition type with a comparable luminosity to 'classical' dwarf galaxies. We measure a systemic heliocentric velocity Vhelio=-21.2+/-1.0km/s. Our survey reveals the clear presence of prolate rotation that is aligned with the peculiar spatial distribution of the youngest stars in Phoenix. We speculate that both features might have arisen from the same event, possibly an accretion of a smaller system. The evolved stellar population of Phoenix is relatively metal-poor (<[Fe/H]>=-1.49+/-0.04dex) and shows a large metallicity spread (sigma_[Fe/H]_=0.51+/-0.04dex), with a pronounced metallicity gradient of -0.13+/-0.01dex/arcmin similar to luminous, passive dwarf galaxies. We also report a discovery of an extremely metal-poor star candidate in Phoenix and discuss the importance of correcting for spatial sampling when interpreting the chemical properties of galaxies with metallicity gradients. This study presents a major leap forward in our knowledge of the internal kinematics of the Phoenix transition type dwarf galaxy and the first wide area spectroscopic survey of its metallicity properties.
- ID:
- ivo://CDS.VizieR/J/A+A/439/1137
- Title:
- PHOENIX model chromospheres of M dwarfs
- Short Name:
- J/A+A/439/1137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an extensive identification catalog of chromospheric emission lines in the optical range. The data were obtained with ESO's Kueyen telescope equipped with the UVES spectrograph from March, 13th to 16th in 2002. The instrument was operated in dichroic mode (spectral coverage from 3030 to 3880 and from 4580 to 6680{AA}). The data for the stars Prox Cen, UV Ceti and LHS 292 were obtained with the same instrument in winter 2000/2001 with a monochroic setup providing only the blue part of the spectrum. We tabulated measured wavelength, equivalent width (EW) and FWHM for every line and star and also provide the rest wavelength from the Moore catalog which was used for identification (Moore 1972). Few lines were identified with the NIST database. The spectra were all corrected for radial velocity besides Kelu-1, DENIS-P J1058.7-1548 and 2MASSI J1315309-264951. DENIS-P J1058.7-1548 has no detected lines, and therefore no data in the table.
- ID:
- ivo://CDS.VizieR/J/A+A/589/A49
- Title:
- Photometric brown-dwarf classification
- Short Name:
- J/A+A/589/A49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a homogeneous sample of 1361 L and T dwarfs brighter than J=17.5 (of which 998 are new), from an effective area of 3070deg^2^, classified by the photo-type method to an accuracy of one spectral sub-type using izY JHKW1W2 photometry from SDSS+UKIDSS+WISE. Other than a small bias in the early L types, the sample is shown to be effectively complete to the magnitude limit, for all spectral types L0 to T8. The nature of the bias is an incompleteness estimated at 3% because peculiar blue L dwarfs of type L4 and earlier are classified late M. There is a corresponding overcompleteness because peculiar red (likely young) late M dwarfs are classified early L. Contamination of the sample is confirmed to be small: so far spectroscopy has been obtained for 19 sources in the catalogue and all are confirmed to be ultracool dwarfs. We provide coordinates and izY JHKW1W2 photometry of all sources. We identify an apparent discontinuity, {Delta}m~0.4mag., in the Y-K colour between spectral types L7 and L8. We present near-infrared spectra of nine sources identified by photo-type as peculiar, including a new low-gravity source ULAS J005505.68+013436.0, with spectroscopic classification L2{gamma}. We provide revised izYJHKW1W2 template colours for late M dwarfs, types M7 to M9.
- ID:
- ivo://CDS.VizieR/J/A+AS/140/29
- Title:
- Photometric monitoring of 47 late-type stars
- Short Name:
- J/A+AS/140/29
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present continuous multicolor photometry for 47 stars from October 1996 through June 1997. Altogether, 7073 V(RI)_c_, UBV, and by data points, each the average of three individual readings, were acquired with three automatic photoelectric telescopes (APTs) at Fairborn Observatory in southern Arizona. Most of our targets are chromospherically active single and binary stars of spectral type G to K but there are also four pre-main-sequence objects and three pulsating stars in our sample. The light variability is generally due to rotational modulation of an asymmetrically spotted stellar surface and therefore precise rotational periods and their seasonal variations are determined from Fourier analysis. We also report on photometric variations of {gamma} CrB (A0V) with a period of 0.44534 days. All data are available in numerical form.
- ID:
- ivo://CDS.VizieR/J/ApJ/781/4
- Title:
- Photometry of high proper motion objects from WISE
- Short Name:
- J/ApJ/781/4
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- I have used multi-epoch astrometry from the Wide-field Infrared Survey Explorer to perform a search for a distant companion to the Sun via its parallactic motion. I have not found an object of this kind down to W2=14.5. This limit corresponds to analogs of Saturn and Jupiter at 28000 and 82000AU, respectively, according to models of the Jovian planets by Fortney and coworkers. Models of brown dwarfs by Burrows and coworkers predict fainter fluxes at a given mass for the age of the solar system, producing a closer distance limit of 26000 AU for a Jupiter-mass brown dwarf. These constraints exclude most combinations of mass and separation at which a solar companion has been suggested to exist by various studies over the years.
- ID:
- ivo://CDS.VizieR/II/25
- Title:
- Photometry of orange-red CaI triplet in Late-Type Stars
- Short Name:
- II/25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Calcium absorption lines were measured using narrow-band photometry on 296 high and low velocity G8-K5 stars of all luminosity classes. Because the blue-violet region of the stellar spectra is too crowded for narrow-band photometry, this investigation of abundance involved measurements of the orange-red CaI triplet 4(3)P-5(3)S, with wavelengths 6102.7, 6122.2 and 6162.2{AA}. "Calcium triplet ratio" is defined as "the measured light intensity ratios, comparison/central regions, calibrated in terms of a standard lamp as described in previous Cambridge papers". The catalog (table I of paper) includes HD number, (B-V) color index, Mg b ratio, H{alpha} ratio, Calcium triplet ratio, and a running number.
- ID:
- ivo://CDS.VizieR/II/45
- Title:
- Photometry of strong CN stars
- Short Name:
- II/45
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A group of 185 late G and K giants, selected from the US Naval Observatory Catalog of Photoelectric Observations (Cat. II/4) because they had Ultraviolet deficiences, were observed with the intermediate band photometric system of the David Dunlap Observatory (defined by McClure and van den Bergh 1968AJ.....73..313M). The DDO photometry is included in Cat. II/17.
- ID:
- ivo://CDS.VizieR/J/MNRAS/482/5379
- Title:
- Physical & orbital properties of detached EBs
- Short Name:
- J/MNRAS/482/5379
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have identified and photometrically characterized a sample of 230 detached close-orbiting eclipsing binaries with low-mass main-sequence components (LMMS) from the Catalina Sky Survey. These low-mass stars have both components below 1.0M_{sun}_, orbital periods shorter than 2-days and effective temperatures below to 5720K. The adopted method provided a robust estimate of stellar parameters (as mass and fractional radius) by using only light curves and photometric colors, since no spectroscopic information was available for these objects. Each light curve was modeled with the JKTEBOP code together with an asexual genetic algorithm to obtain the most coherent values for the fitted parameters. This new sample of short-period detached eclipsing binaries, with low-mass main-sequence stars (LMMS) considerably increases the number of previously known systems. Which allows us to derive masses and radii in statistically significant samples for the investigation of the correlation between radius inflation and other basic stellar parameters.
