Related papers: The Evolved Red Stellar Content of M32
We have used deep ACS/WFC images of M33 to check nature of extended objects detected by the ground based survey of Zloczewski et al. (2008). A total of 24 candidates turned out to be genuine compact stellar clusters. In addition we detected…
We have used the CFHT REDEYE infrared camera to obtain deep J and K' images of four fields in the globular cluster M13. The composite K, J-K color-magnitude diagram (CMD) extends from the upper red giant branch (RGB) to 2 magnitudes below…
Using new narrowband color observations of early-type galaxies in clusters, we reconstruct the color-magnitude relation (CMR) with a higher degree of accuracy than previous work. We then use the spectroscopically determined ages and…
We present a study of the evolved stellar populations in the dwarf spheroidal galaxy Fornax based on JHK imaging photometry. The observations cover an 18.5x18.5 arcmin central area with a mosaic of NTT/SOFI images. Our data sample all the…
Observations in the IJKs wave bands covering the central 20'x20' of the Local Group galaxy NGC 6822 have been performed from the William Herschel Telescope in La Palma. They have allowed us to characterize, for the first time in the…
We examine the star-forming history (SFH) of the M31 disk during the past few hundred Myr. The luminosity functions (LFs) of main sequence stars at distances R_GC > 21 kpc (i.e. > 4 disk scale lengths) are matched by models that assume a…
JHK images obtained with the Canada-France-Hawaii Telescope (CFHT) Adaptive Optics Bonnette (AOB) are used to investigate the near-infrared photometric properties of red giant branch (RGB) and horizontal branch (HB) stars in eight…
Deep J, H, and K images are used to probe the evolved stellar contents in the central regions of the Sculptor group galaxies NGC55, NGC300, and NGC7793. The brightest stars are massive red supergiants (RSGs) with K ~ 15 - 15.5. The peak RSG…
We present high-resolution optical and near-infrared HST observations of two adjacent regions in the fossil starburst region in M82, B1 and B2. Age estimates date the cluster population in the fossil starburst between ~2 x 10^8 and ~10 x…
We present near-infrared JHKs imaging as well as K-band multi-object spectroscopy of the massive stellar content of W3 Main using LUCI at the LBT. We confirm 13 OB stars by their absorption line spectra in W3 Main and spectral types between…
We have carried out an infrared search for obscured AGB stars in the Magellanic Clouds. The survey uncovered a number of obscured AGB stars as well as some supergiants with infrared excess. We present photometry of the sources and discuss…
We derive ages, metallicities and [alpha/Fe] ratios from the integrated spectra of 23 globular clusters in M31, by employing multivariate fits to two stellar population models. In parallel we analyze spectra of 21 Galactic globular clusters…
Observations in the near-infrared domain showed the presence of the flat core of bright late-type stars inside $\sim 0.5\,{\rm pc}$ from the Galactic center supermassive black hole (Sgr A*), while young massive OB/Wolf-Rayet stars form a…
Stellar photometry of nearby irregular galaxies of the Local Group is used to identify and study the young and old stellar populations of these galaxies. An analysis of the spatial distributions of stars of different ages in face-on…
We present color-magnitude diagrams and luminosity functions of stars in two halo regions of the irregular galaxy in M82, based on F555W and F814W photometry taken with the Hubble Space Telescope and Wide Field Planetary Camera 2. The…
We present the first detection of 24 {\mu}m variability in 24 sources in the Local Group galaxy M33. These results are based on 4 epochs of MIPS observations, which are irregularly spaced over ~750 days. We find that these sources are…
We present theoretical surface-brightness fluctuations (SBF) amplitudes for single-burst stellar populations of young and intermediate age ($25 Myr \leq t \leq 5 Gyr$), and $Z=0.0003$, 0.001, 0.004, 0.008, 0.01, 0.02, and 0.04. We pay…
Broad-band near-infrared images are used to probe the photometric properties of the brightest asymptotic giant branch (AGB) stars within 2 arcminutes of the centers of the dwarf elliptical galaxies NGC 147, NGC 185, and NGC 205. Based on…
Mid-infrared observations (3.6 - 24 microns) of normal giant elliptical galaxies with the Spitzer space telescope are consistent with pure populations of very old stars with no evidence of younger stars. Most of the stars in giant…
We present a demographic analysis of integrated star formation and gas properties for a sample of galaxies representative of the overall population at z~0. This research was undertaken in order to characterise the nature of star formation…