We construct an integrated spectrum of the intermediate-age, solar-metallicity Galactic cluster M67, from individual spectroscopic observations of bona fide cluster members. The spectrum so obtained is used as a template to test our stellar population synthesis models, in an age and metallicity regime where such models remain largely untested. As a result, we demonstrate that our models predict a spectroscopic age of 3.5+/-0.5Gyr for M67, which is the same age we obtain from fitting isochrones to the color-magnitude diagram of the cluster. Full consistency is reached when using either H{beta}, H{gamma}, or H{delta} as the age indicator. We also check if the models, when applied to the cluster integrated spectrum, predict elemental abundances in agreement with the known detailed abundance pattern of the cluster. The models also pass the latter test, by predicting the abundances of iron, magnesium, carbon, and nitrogen in agreement with detailed abundance analyses of cluster stars to within 0.1dex. Encouraged by the high degree of consistency of our models, we apply them to the study of the integrated spectrum of the central 3" of the compact elliptical galaxy M32.
Lick line-index and photometry of globular clusters
Short Name:
J/A+A/415/123
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalog contains Lick line-index and photometric measurements of extragalactic globular clusters in seven early-type galaxies (NGC 1380, 2434, 3115, 3379, 3585, 5846, and 7192) with different morphological types (E/S0) located in field and group/cluster environments. High-quality spectra were taken with the FORS2 instrument at ESO's Very Large Telescope. ~50% of our data allows an age resolution {Delta}t/t~0.3 and a metallicity resolution ~0.25-0.4dex, depending on the absolute metallicity. Globular cluster candidates are selected from deep B, V, R, I, K FORS2/ISAAC photometry with 80-100% success rate inside one effective radius. Using combined optical/near-infrared colour-colour diagrams we present a method to efficiently reduce fore-/background contamination down to <~10%.
Using high-quality data on 149 galaxies within 10Mpc, I find no correlation between luminosity and peculiar velocity at all. There is no unequivocal sign on scales of 12Mpc of the expected gravitational effect of the brightest galaxies, in particular infall toward groups, or of infall toward the supergalactic plane on any scale. Either dark matter is not distributed in the same way as luminous matter in this region, or peculiar velocities are not due to fluctuations in mass. The sensitivity of peculiar velocity studies to the background model is highlighted.
We present new V-band differential photometry and radial velocity measurements of the unevolved, 1.18 day period, F+G-type, double-lined eclipsing binary VZ Cep. We determine accurate values for the absolute masses, radii, and effective temperatures.
We present results from light curve fits to the photometry of 13 chromospherically active stars, covering the time evolution of the rotational phase of their primary light curve minimum and the light curve amplitude.
Light curve and radial velocities for 7 host stars
Short Name:
J/AJ/162/7
Date:
18 Mar 2022 09:35:03
Publisher:
CDS
Description:
We report the discovery and characterization of seven transiting exoplanets from the HATNet survey. The planets, which are hot Jupiters and Saturns transiting bright Sun-like stars, include: HAT-P-58b (with mass M_p_=0.37M_J_, radius R_p_=1.33R_J_, and orbital period P=4.0138days), HAT-P-59b (M_p_=1.54M_J_, R_p_=1.12R_J_, P=4.1420days), HAT-P-60b (M_p_=0.57M_J_, R_p_=1.63R_J_, P=4.7948days), HAT-P-61b (M_p_=1.06M_J_, R_p_=0.90R_J_, P=1.9023days), HAT-P-62b (M_p_=0.76M_J_, R_p_=1.07R_J_, P=2.6453days), HAT-P-63b (M_p_=0.61M_J_, R_p_=1.12R_J_, P=3.3777days), and HAT-P-64b (M_p_=0.58M_J_, R_p_= 1.70R_J_, P=4.0072days). The typical errors on these quantities are 0.06M_J_, 0.03R_J_, and 0.2s, respectively. We also provide accurate stellar parameters for each of the host stars. With V=9.710{+/-}0.050mag, HAT-P-60 is an especially bright transiting planet host, and an excellent target for additional follow-up observations. With R_p_=1.703{+/-}0.070R_J_, HAT-P-64b is a highly inflated hot Jupiter around a star nearing the end of its main-sequence lifetime, and is among the largest known planets. Five of the seven systems have long-cadence observations by TESS which are included in the analysis. Of particular note is HAT-P-59 (TOI-1826.01) which is within the northern continuous viewing zone of the TESS mission, and HAT-P-60, which is the TESS candidate TOI-1580.01.
BD+42 2782 was recently discovered to be a variable star with a W UMa-type, eclipsing-binary light curve. We have obtained the first photoelectric light curves (R_C_, I_C_) and also the first radial velocity curves for this binary.
Multiwavelength observations of the optical afterglow of GRB 050319 were performed from 1.31 to 9.92hr after the burst. Our R-band light curves, combined with other published data, can be described by the smooth broken power-law function, with {alpha}_1_=-0.84+/-0.02 to {alpha}_2_=-0.48+/-0.03, 0.04 days after the gamma-ray burst. The optical light curves are characterized by shallow decays as was also observed in the X-rays which may have a similar origin, related to energy injection. However, our observations indicate that there is still a puzzle concerning the chromatic breaks in the R-band light curve (at 0.04 days) and the X-ray light curve (at 0.004 days) that remains to be solved.
We present multicolor optical observations of the nearby (z=0.1685) gamma-ray burst GRB 030329 obtained with the same instrumentation over a time period of 6 hours, for a total of an unprecedented 475 quasi-simultaneous BVR observations.
We perform lightcurve inversion for 491 asteroids to retrieve phase curve parameters, rotation periods, pole longitudes and latitudes, and convex and triaxial ellipsoid shapes by using the sparse photometric observations from Gaia Data Release 2 and the dense ground-based observations from the DAMIT data base. We develop a method for the derivation of reference absolute magnitudes and phase curves from the Gaia data, allowing for comparative studies among hundreds of asteroids.
