- ID:
- ivo://CDS.VizieR/J/AJ/159/24
- Title:
- Spectroscopy & Kepler data of the EB star V404 Lyr
- Short Name:
- J/AJ/159/24
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first high-resolution spectra for the eclipsing binary V404Lyr showing {gamma}Dor pulsations, which we use to study its absolute properties. By fitting models to the disentangling spectrum of the primary star, we found that it has an effective temperature of T_eff,1_=7330{+/-}150K and a rotational velocity of v_1_sini=148{+/-}18km/s. The simultaneous analysis of our double-lined radial velocities and the pulsation-subtracted Kepler data gives us accurate stellar and system parameters of V404Lyr. The masses, radii, and luminosities are M1=2.17{+/-}0.06M_{sun}_, R1=1.91{+/-}0.02R_{sun}_, and L1=9.4{+/-}0.8L_{sun}_ for the primary, and M2=1.42{+/-}0.04M_{sun}_, R2=1.79{+/-}0.02R_{sun}_, and L2=2.9{+/-}0.2L_{sun}_ for the secondary. The tertiary component orbiting the eclipsing pair has a mass of M_3b_=0.71{+/-}0.15M_{sun}_ in an orbit of P_3b_=642{+/-}3d, e_3b_=0.21{+/-}0.04, and a_3b_=509{+/-}2R_{sun}_. The third light of l_3_=4.1{+/-}0.2% could be partly attributable to the K-type circumbinary object. By applying a multiple frequency analysis to the eclipse-subtracted light residuals, we detected 45 frequencies with signal-to-noise amplitude ratios larger than 4.0. Identified as independent pulsation modes, seven frequencies (f_1_-f_6_, f_9_), their new pulsation constants, and the location in the Hertzsprung-Russell diagram indicate that the pulsating primary is a {gamma}Dor-type variable star.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/395/855
- Title:
- Spectroscopy (310-1040nm) of HH 202
- Short Name:
- J/MNRAS/395/855
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of deep echelle spectrophotometry of the brightest knot of the Herbig-Haro object HH 202 in the Orion Nebula - HH 202-S - using the Ultraviolet Visual Echelle Spectrograph in the spectral range from 3100 to 10400{AA} The high spectral resolution of the observations has permitted to separate the component associated with the ambient gas from that associated with the gas flow. We derive electron densities and temperatures from different diagnostics for both components, as well as the chemical abundances of several ions and elements from collisionally excited lines, including the first determinations of Ca^+^ and Cr^+^ abundances in the Orion Nebula. We also calculate the He+, C^2+^, O+ and O^2+^ abundances from recombination lines.
- ID:
- ivo://CDS.VizieR/J/ApJ/834/9
- Title:
- Spectroscopy obs. of LeoA, Aqr & Sgr dwarf gal.
- Short Name:
- J/ApJ/834/9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Keck/DEIMOS spectroscopy of individual stars in the relatively isolated Local Group dwarf galaxies Leo A, Aquarius, and the Sagittarius dwarf irregular galaxy. The three galaxies-but especially Leo A and Aquarius-share in common delayed star formation histories (SFHs) relative to many other isolated dwarf galaxies. The stars in all three galaxies are supported by dispersion. We found no evidence of stellar velocity structure, even for Aquarius, which has rotating HI gas. The velocity dispersions indicate that all three galaxies are dark-matter-dominated, with dark-to-baryonic mass ratios ranging from 4.4_-0.8_^+1.0^ (SagDIG) to 9.6_-1.8_^+2.5^ (Aquarius). Leo A and SagDIG have lower stellar metallicities than Aquarius, and they also have higher gas fractions, both of which would be expected if Aquarius were further along in its chemical evolution. The metallicity distribution of Leo A is inconsistent with a closed or leaky box model of chemical evolution, suggesting that the galaxy was pre-enriched or acquired external gas during star formation. The metallicities of stars increased steadily for all three galaxies, but possibly at different rates. The [{alpha}/Fe] ratios at a given [Fe/H] are lower than that of the Sculptor dwarf spheroidal galaxy, which indicates more extended SFHs than Sculptor, consistent with photometrically derived SFHs. Overall, the bulk kinematic and chemical properties for the late-forming dwarf galaxies do not diverge significantly from those of less delayed dwarf galaxies, including dwarf spheroidal galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/853/36
- Title:
- Spectroscopy obs. of 20 Planck gal. cluster cand.
- Short Name:
- J/ApJ/853/36
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Gemini and Keck spectroscopic redshifts and velocity dispersions for 20 clusters detected via the Sunyaev-Zel'dovich (SZ) effect by the Planck space mission, with estimated masses in the range 2.3x10^14^M_{sun}_<M_500_^Pl^<9.4x10^14^M_{sun}_. Cluster members were selected for spectroscopic follow-up with Palomar, Gemini, and Keck optical and (in some cases) infrared imaging. Seven cluster redshifts were measured for the first time with this observing campaign, including one of the most distant Planck clusters confirmed to date, at z=0.782+/-0.010, PSZ2 G085.95+25.23. The spectroscopic redshift catalogs of members of each confirmed cluster are included as online tables. We show the galaxy redshift distributions and measure the cluster velocity dispersions. The cluster velocity dispersions obtained in this paper were used in a companion paper to measure the Planck mass bias and to constrain the cluster velocity bias.
- ID:
- ivo://CDS.VizieR/J/A+A/394/395
- Title:
- Spectroscopy of Abell 222 and Abell 223
- Short Name:
- J/A+A/394/395
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This spectroscopic study of the neighboring massive clusters Abell 222 and Abell 223 is based on MOS using EMMI at the NTT. Photometry was obtained from WFI images taken with the ESO/MPG 2.2m telescope. Data for objects coincident with objects from Proust et al., 2000A&A...355..443P, is listed for comparison.
- ID:
- ivo://CDS.VizieR/J/AJ/124/2453
- Title:
- Spectroscopy of active galaxies in nearby clusters
- Short Name:
- J/AJ/124/2453
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used optical spectroscopy to investigate the active galaxy populations in a sample of 20 nearby Abell clusters. The targets were identified on the basis of 1.4GHz radio emission, which identifies them as either active galactic nuclei (AGNs) or galaxies forming stars at rates comparable to or greater than that of the Milky Way. The spectra were used to characterize the galaxies via their emission and absorption features.
- ID:
- ivo://CDS.VizieR/J/MNRAS/383/845
- Title:
- Spectroscopy of AE Circinus
- Short Name:
- J/MNRAS/383/845
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new optical spectroscopy and photometry, Two-Micron All-Sky Survey (2MASS) infrared observations and 24yr of combined American Association of Variable Star Observers (AAVSO) and Association Francaise des Observateurs d'Etoiles Variables (AFOEV) photometry of the symbiotic star candidate AE Cir. The long-term light curve is characterized by outbursts lasting several years and having a slow decline of ~2x10^-4^mag/d. The whole range of variability of the star in the V band is about 4mag. The periodogram of the photometric data reveals strong signals at ~342 and 171d. The presence of the emission feature at {lambda}6830{AA} at minimum and the detection of absorption lines of a ~K5 type star confirm the symbiotic classification and suggest that AE Cir is a new member of the small group of s-type yellow symbiotic stars. We estimate a distance of 9.4kpc. Our spectrum taken at the high state shows a much flatter spectral energy distribution, the disappearance of the {lambda}6830{AA} emission feature and the weakness of the HeII 4686 emission relative to the Balmer emission lines. Our observations indicate the presence of emission-line flickering in time-scales of minutes in 2001. The peculiar character of AE Cir is revealed in the visibility of the secondary star at the high and low state, the light curve resembling a dwarf nova superoutburst and the relatively short low states. The data are hard to reconciliate with standard models for symbiotic star outbursts.
- ID:
- ivo://CDS.VizieR/J/A+A/328/261
- Title:
- Spectroscopy of Alpha Cen
- Short Name:
- J/A+A/328/261
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This table presents the results of a spectroscopic analysis (differentially to the Sun) of the two components of the binary system Alpha Centauri. This analysis has been carried out on the basis of extensive high resolution and high signal-to-noise spectra taken at the European Southern Observatory (La Silla, Chile).
2529. Spectroscopy of Be stars
- ID:
- ivo://CDS.VizieR/J/A+A/378/861
- Title:
- Spectroscopy of Be stars
- Short Name:
- J/A+A/378/861
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 270 spectra enclosed are those used in the atlas and are described in the Table 1 of the paper: stars with magnitudes and spectral types, dates of observations and other data. All are normalized and corrected from the radial velocity due to Earth movement, but not corrected from the radial velocity of the star itself. The heliocentric Julian day of the mid-exposure appears in the header with a comment keyword. Very often it cannot be derived by a simple formula from the beginning and the time exposure, when the spectrum is the result of the sum of several successive ones, or when clouds have obliged to interrupt the exposure. For this reason, it is always indicated. The HD number of the star appears always in the name of the file, with additional letters to distinguish the different spectra of a same star. The tracings of the atlas (72 FITS files) are described in the subsection 2.4 of the paper and available with the electronic version.
- ID:
- ivo://CDS.VizieR/J/ApJ/700/1216
- Title:
- Spectroscopy of Be stars in open clusters
- Short Name:
- J/ApJ/700/1216
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We recently discovered a large number of highly active Be stars in the open cluster NGC 3766, making it an excellent location to study the formation mechanism of Be star disks. To explore whether similar disk appearances and/or disappearances are common among the Be stars in other open clusters, we present here multiple epochs of H{alpha} spectroscopy for 296 stars in eight open clusters. We identify 12 new transient Be stars and confirm 17 additional Be stars with relatively stable disks. By comparing the H{alpha} equivalent widths to the photometric y-H{alpha} colors, we present a method to estimate the strength of the H{alpha} emission when spectroscopy is not available. For a subset of 128 stars in four open clusters, we also use blue optical spectroscopy and available Stromgren photometry to measure their projected rotational velocities, effective temperatures, and polar surface gravities. We combine our Be star detections from these four clusters to investigate physical differences between the transient Be stars, stable Be stars, and normal B-type stars with no line emission. Both types of Be stars are faster rotating populations than normal B-type stars, and we find no significant physical differences between the transient and stable Be stars in our sample.
