Related papers: Trumpler 20 - an old and rich open cluster
Infrared JKs-band photometry of the Galactic globular clusters M15 and, for the first time, M56 is presented. We estimated the reddening (E(B-V)=0.18+/-0.08 mag) and distance modulus ((m-M)_V=15.43+/-0.30 mag) towards the poorly studied…
We present an investigation of the open cluster Trumpler 2 using Gaia DR3 photometric, astrometric and spectroscopic data. 92 stars were identified as likely members of the cluster, with membership probabilities greater than 0.5. The mean…
With an apparent cluster diameter of 1.5{\deg} and an age of ~4 Myr, Trumpler 37 is an ideal target for photometric monitoring of young stars as well as for the search of planetary transits, eclipsing binaries and other sources of…
Context. The existence of lithium-rich low-mass red giant stars still represents a challenge for stellar evolution models. Stellar clusters are privileged environments for this kind of investigation. Aims. To investigate the chemical…
We have obtained spectra with resolution 2.5 Angstroms in the region 7500-9500 Angstroms for 116 red giants in 5 Galactic globular clusters and 6 old open clusters (5 with published metallicities, and one previously unmeasured). The…
We have identified a clustering of red galaxies from deep optical/IR images obtained as part of the Institute for Astronomy Deep Survey. Photometric spectral-energy distributions indicate that most of these galaxies comprise nearly pure old…
Fundamental astrophysical parameters have been derived for 20 open clusters (O\!Cs) using CCD~$U\!BV\!(RI)_C$ photometric data observed with the 84~cm telescope at the San Pedro M\'artir National Astronomical Observatory, M\'exico. The…
We present new photometry for the Galactic thick disk globular cluster Palomar 11 extending well past the main sequence turn-off in the V and I bands. This photometry shows noticeable red giant and subgiant branches. The difference in…
We present UBV photometry of the highly reddened and poorly studied open cluster Berkeley 55, revealing an important population of B-type stars and several evolved stars of high luminosity. Intermediate resolution far-red spectra of several…
We present homogeneous $V,I$ CCD photometry of nine stellar fields in the two inner quadrants of the Galactic plane. The lines-of-view to most of these fields aim in the direction of the very inner Galaxy, where the Galactic field is very…
NGC 6819 is a richly populated, older open cluster situated within the Kepler field. A CCD survey of the cluster on the uvbyCaHbeta system, coupled with proper-motion membership, has been used to isolate 382 highly probable, single-star…
We observed the Galactic open cluster Berkeley 50 in order to determine its stellar content, distance, and age. We obtained UBV photometry of 1145 stars in a 12.3' $\times$ 12.3' field, and used Gaia proper motions and parallaxes to…
We present a BVI optical photometric study of the old open cluster Ruprecht 6 using the data obtained with the SMARTS 1.0 m telescope at the CTIO, Chile. Its color-magnitude diagrams show the clear existence of the main-sequence stars, of…
We present UBVI photometry of the old open cluster NGC 1193. Color-magnitude diagrams (CMDs) of this cluster show a well defined main sequence and a sparse red giant branch. For the inner region of r<50 arcsec, three blue straggler…
NGC 2420 is a $\sim$2 Gyr-old well-populated open cluster that lies about 2 kpc beyond the solar circle, in the general direction of the Galactic anti-center. Most previous abundance studies have found this cluster to be mildly metal-poor,…
Using the highest-resolution X-ray observation of the Trumpler 15 star cluster taken by the Chandra X-ray Observatory, we estimate the total size of its stellar population by comparing the X-ray luminosity function of the detected sources…
We report on high resolution Echelle spectroscopy of 20 giant stars in the Galactic old open clusters NGC 6791 obtained with Hydra at the WIYN telescope. High precision radial velocity allow us to isolate 15 {\it bona fide} cluster members.…
We present deep CCD BVI photometry of the distant, old open cluster Berkeley 22, covering from the red giants branch (RGB) to about 6 magnitudes below the main sequence (MS) turn-off. Using the synthetic Colour - Magnitude Diagram method…
Deep color-magnitude diagrams are presented for poorly known open clusters Cr 261, Be 18, Be 54, Tr 5 and BH176. All clusters are old objects with age\geq 4 Gyr. BH176 is either old open cluster or young globular cluster. Extremely red…
We present the analysis of high resolution spectra of six red giant stars in the old open cluster Collinder 261. Reddening values for individual stars, derived from the relation between colours and temperatures (deduced from our fully…