- ID:
- ivo://CDS.VizieR/J/ApJ/682/L117
- Title:
- A spectroscopic orbit for Regulus
- Short Name:
- J/ApJ/682/L117
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a radial velocity study of the rapidly rotating B star Regulus that indicates the star is a single-lined spectroscopic binary. The orbital period (40.11 days) and probable semimajor axis (0.35AU) are large enough that the system is not interacting at present. However, the mass function suggests that the secondary has a low mass (M_2_>0.30M_{sun}_), and we argue that the companion may be a white dwarf. Such a star would be the remnant of a former mass donor that was the source of the large spin angular momentum of Regulus itself.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/251/482
- Title:
- A spectroscopic survey of faint QSOs
- Short Name:
- J/MNRAS/251/482
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/AJ/155/240
- Title:
- A spectroscopic survey of field RHB stars
- Short Name:
- J/AJ/155/240
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A metallicity, chemical composition, and kinematic survey has been conducted for a sample of 340 candidate field red horizontal-branch (RHB) stars. Spectra with high resolution and high signal-to-noise ratio were gathered with the McDonald Observatory 2.7 m Tull and the Hobby-Eberly Telescope echelle spectrographs, and were used to determine effective temperatures, surface gravities, microturbulent velocities, [Fe/H] metallicities, and abundance ratios [X/Fe] for seven {alpha} and Fe-group species. The derived temperatures and gravities confirm that at least half of the candidates are true RHB stars, with (average) parameters T_eff_~5000 K and log g~2.5. From the {alpha} abundances alone, the thin and thick Galactic populations are apparent in our sample. Space motions for 90% of the program stars were computed from Hipparcos and Gaia parallaxes and proper motions. Correlations between chemical compositions and Galactic kinematics clearly indicate the existence of both thin-disk and thick-disk RHB stars.
1164. asPIC1.1 catalogue
- ID:
- ivo://CDS.VizieR/J/A+A/653/A98
- Title:
- asPIC1.1 catalogue
- Short Name:
- J/A+A/653/A98
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- The ESA PLAnetary Transits and Oscillations of stars (PLATO) mission will search for terrestrial planets in the habitable zone of solar-like stars. Because of telemetry limitations PLATO targets need to be pre-selected. In this paper we present an all sky catalog that will be fundamental to select the best PLATO fields and the most promising target stars, derive their fundamental parameters, analyze the instrumental performances and then plan and optimize follow-up observations. This catalog also represents a valuable resource for the general definition of stellar samples optimized for the search of transiting planets. We used Gaia Data Release 2 (DR2) astrometry and photometry and 3D maps of the local interstellar medium to isolate FGK (V<=13) and M(V<=16) dwarfs and subgiant stars. We present the first public release of the all sky PLATO Input Catalog (asPIC1.1) containing a total of 2675539 stars among which 2378177 FGK dwarfs and subgiants and 297362 M dwarfs. The median distance in our sample is 428pc for FGK stars and 146 pc for M dwarfs, respectively. We derived the reddening of our targets and developed an algorithm to estimate stellar fundamental parameters (Teff, radius, mass) from astrometric and photometric measurements. We show that our overall (internal+external) uncertainties on the stellar parameters determination is ~230K (4%) for the effective temperatures, ~0.1R_{sun}_ (9%) for the stellar radii and ~0.1M_{sun}_ (11%) for the stellar mass. We release a special target list containing all known planet hosts cross-matched with our catalog.
- ID:
- ivo://CDS.VizieR/J/ApJ/705/68
- Title:
- A Spitzer ultradeep survey (SUUSS)
- Short Name:
- J/ApJ/705/68
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We carried out an unbiased, spectroscopic survey using the low-resolution module of the infrared spectrograph (IRS) onboard Spitzer targeting two 2.6 square arcminute regions in the GOODS-North field. The IRS was used in a spectral mapping mode with 5hr of effective integration time per pixel. One region was covered between 14 and 21um and the other between 20 and 35um. We extracted spectra for 45 sources. About 84% of the sources have reported detections by GOODS at 24um, with a median f_{nu}_(24um)~100uJy. All but one source are detected in all four IRAC bands, 3.6 to 8um. We use a new cross-correlation technique to measure redshifts and estimate IRS spectral types; this was successful for ~60% of the spectra. Fourteen sources show significant polycyclic aromatic hydrocarbon emission, four mostly SiO absorption, eight present mixed spectral signatures (low PAH and/or SiO) and two show a single line in emission. For the remaining 17, no spectral features were detected. Redshifts range from z~0.2 to z~2.2, with a median of 1. IR luminosities are roughly estimated from 24um flux densities, and have median values of 2.2x10^11^L_{sun}_ and 7.5x10^11^L_{sun}_ at z~1 and z~2, respectively. This sample has fewer active galactic nuclei than previous faint samples observed with the IRS, which we attribute to the fainter luminosities reached here.
- ID:
- ivo://CDS.VizieR/J/AJ/138/1116
- Title:
- A Spitzer view of NGC 2264
- Short Name:
- J/AJ/138/1116
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have performed mid-IR photometry of the young open cluster NGC 2264 using the images obtained with the Spitzer Space Telescope Infrared Array Camera and Multiband Imaging Photometer for Spitzer instruments and presented a normalized classification scheme of young stellar objects in various color-color diagrams to make full use of the information from multicolor photometry. These results are compared with the classification scheme based on the slope of the spectral energy distribution (SED). From the spatial distributions of Class I and II stars, we have identified two subclusterings of Class I objects in the CONE region of Sung et al. (Cat. J/AJ/135/441). The disked stars in the other star-forming region S Mon are mostly Class II objects. In addition, we have derived a somewhat higher value of the primordial disk fraction for NGC 2264 members located below the main pre-main-sequence locus (so-called BMS stars). This result supports the idea that BMS stars are young stars with nearly edge-on disks.
- ID:
- ivo://CDS.VizieR/J/A+A/649/A60
- Title:
- Assignment & prediction of formaldoxime (CH2NOH)
- Short Name:
- J/A+A/649/A60
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Among the six atoms of N-containing molecules with the formula of CH_3_NO, only formamide (H_2_NCHO), the most stable structural isomer, has been detected in the interstellar medium (ISM). The formaldoxime isomer may be formed, for example, by the reaction of formaldehyde (H_2_CO) or methanimine (H_2_CNH) and hydroxylamine (H_2_NOH), which are all detected in the ISM. The lack of high accuracy millimeter- and submillimeter-wave measurements hinders the astronomical search for formaldoxime. The aim of this work is to provide the direct laboratory measurement of the millimeter- and submillimeter-wave spectrum of trans-formaldoxime. Formaldoxime was synthesized and its rotational spectrum was recorded at room temperature in a glass flow cell using the millimeter- and submillimeter-wave spectrometer in Lille. The SPFIT program in the CALPGM suite was used to fit the spectrum. Rotational lines of trans-formaldoxime from both the ground state and v_12_=1 vibrational excited states have been measured and assigned from 150 to 660GHz. Spectroscopic constants were derived to the tenth order using both Watson's A and S reduction Hamiltonian.
- ID:
- ivo://CDS.VizieR/B/assocdata
- Title:
- Associated data in VizieR
- Short Name:
- B/assocdata
- Date:
- 20 Mar 2022 05:13:55
- Publisher:
- CDS
- Description:
- The ObsCore VizieR table gather FITS images, spectra and time-series into a single table. The contents are the VizieR associated data, publilished in original article with the tables. The metadata comes from the ObsCore Data Model. ObsCore (Tody et al. 2011) is a standard of the Virtual Observatory used to map images,spectra or time-series resources with standardized metadata.
- ID:
- ivo://CDS.VizieR/J/ApJ/679/239
- Title:
- Associated MgII absorbers
- Short Name:
- J/ApJ/679/239
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We studied a sample of 415 associated (z_abs_~z_em_; relative velocity with respect to QSO in units of c, {beta}<0.01) MgII absorption systems with 1.0<=z_abs_<=1.86, in the spectra of SDSS DR3 QSOs, to determine the dust content and ionization state in the absorbers. We also compared these properties to those of a similarly selected sample of 809 intervening systems ({beta}>0.01), so as to understand their origin. Normalized, composite spectra were derived for absorption line measurements, for the full sample and for several subsamples, chosen on the basis of the line strengths and other absorber and QSO properties. From these, and from the equivalent widths in individual spectra, we conclude that the associated MgII absorbers have higher ionization (higher ratios of the strengths of CIV and MgII lines), than the intervening absorbers. The ionization decreases with increasing {beta}. Average extinction curves were obtained for the subsamples by comparing their geometric mean QSO spectra with those of matching (in z_em_ and i magnitude) samples of QSOs without absorption lines. There is clear evidence for SMC-like dust attenuation in these systems; the 2175{AA} absorption feature is absent. The extinction is almost twice that observed in intervening systems. We reconfirm that QSOs with nonzero FIRST radio flux are intrinsically redder than the QSOs with no detection in the FIRST survey.
- ID:
- ivo://CDS.VizieR/J/A+A/284/233
- Title:
- Association of HII regions and IRAS PSC sources
- Short Name:
- J/A+A/284/233
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
