Related papers: Derived Parameters for NGC 6791 from High-Metallic…

We have analyzed archival far-ultraviolet spectra of the UV-bright star III-60 in the globular cluster NGC 6723 obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) and the Cosmic Origins Spectrograph (COS). We find that the…

Spectral absorption features can be used to constrain the stellar initial mass function (IMF) in the integrated light of galaxies. Spectral indices used at low redshift are in the far red, and therefore increasingly hard to detect at higher…

Deep and extensive CCD photometric observations $UBV(RI)_{C}H_{\alpha}$ were carried out in the area of the open cluster NGC 3293. The new data set allows to see the entire cluster sequence down to $M_{V} \approx +4.5$, revealing that stars…

We use very deep near-infrared photometry of the Hubble Deep Field South taken with ISAAC/VLT to identify a population of high redshift galaxies with rest- frame optical colors similar to those of nearby galaxies. The galaxies are chosen by…

We have identified a large number of possible very low mass members of the cluster IC2391 based primarily on their location in an I versus (R-I)_C CM diagram. We have obtained new photometry and low resolution ($\Delta \lambda = 2.7$ \AA)…

We investigate the nature of the substantial population of high-z galaxies with Js-Ks>2.3 discovered as part of our FIRES survey. This colour cut efficiently isolates z>2 galaxies with red rest-frame optical colors ("Distant Red Galaxies"…

We have used R_C I_C CCD photometry from the Isaac Newton telescope and intermediate resolution spectroscopy from the Gemini North telescope to identify and characterise low-mass (0.15<M/M_sun<1.3) pre-main sequence stars in the young open…

We present low-resolution near-infrared stacked spectra from the 3D-HST survey up to $z=2.0$ and fit them with commonly used stellar population synthesis models: BC03 (Bruzual & Charlot, 2003), FSPS10 (Flexible Stellar Population Synthesis,…

The spectral and reddening properties of 211 highly reddened proper motion members with $V < 15$ mag in 6 young galactic star clusters are investigated using low resolution spectroscopic, broad-band $UBVRIJHK$ and mid-IR data. We report…

The B,V CCD photometry of 916 stars in the field of the high galactic latitude intermediate age open cluster NGC 1245 is presented. The cluster parameters were estimated with the help of V vs (B-V) colour-magnitude diagram (CMD). After…

We present the first detailed analysis of the detached eclipsing binary V15 in the super-metal rich open cluster NGC 6253. We obtain the following absolute parameters: M_p=1.303+-0.006 Msun, R_p=1.71+-0.03 Rsun, L_p=2.98+-0.10 Lsun for the…

We present deep V,I photometry of two $9.4' x 9.4' field in the outer regions of the M33 galaxy. We obtain a robust detection of the luminosity of the Red Giant Branch Tip (I{TRGB}=20.72 +- 0.08) from which we derived a new estimate of the…

Distances and absolute ages for the globular clusters NGC6397, NGC6752, and 47 Tuc are obtained using Main Sequence Fitting. Accurate reddenings and metal abundances (errors of 0.005 mag and 0.04 dex) are obtained by comparing B-V, b-y…

Precision UBVRI photometry of NGC 7789 is combined with Gaia data to map reddening variations across the cluster face. HYDRA spectra, Gaia astrometry, and isochrone fitting constrain the absolute reddening, apparent modulus, and age to…

We fit various colour-magnitude diagrams (CMDs) of the Galactic globular clusters NGC\,6397 and NGC\,6809 (M55) by isochrones from the Dartmouth Stellar Evolution Database (DSED) and Bag of Stellar Tracks and Isochrones (BaSTI) for…

Chandra images present evidence for a non-uniform spatial distribution of discrete X-ray sources in the elliptical galaxy NGC 4261. This non-uniform distribution is inconsistent with the optical morphology of NGC 4261 at greater than a…

We present new isochrone fits to colour-magnitude diagrams of the Galactic globular clusters NGC\,288, NGC\,362, and NGC\,6218 (M12). We utilize a lot of photometric bands from the ultraviolet to mid-infrared by use of data from the {\it…

NGC 6791 is one of the most studied open clusters, it is massive ($\sim5000\,M_{\odot}$), located at the solar circle, old ($~8\,$Gyr) and yet the most metal-rich cluster (${\rm [Fe/H]}\simeq0.4$) known in the Milky Way. By performing an…

The open cluster NGC 6791 is among the oldest, most massive and metal-rich open clusters in the Galaxy. High-resolution $H$-band spectra from the Apache Point Observatory Galactic Evolution Experiment (APOGEE) of 11 red giants in NGC 6791…

We present a 1620 A image of the nearby globular cluster NGC 6752 obtained with the Ultraviolet Imaging Telescope (UIT) during the Astro-2 mission of the Space Shuttle Endeavour in 1995 March. An ultraviolet-visible color-magnitude diagram…