Related papers: Fast rotating Blue Stragglers in the globular clus…

Blue lurkers (BLs) are rejuvenated main-sequence stars hidden among normal main-sequence stars on color-magnitude diagrams of star clusters. In comparison, the blue straggler stars, formed via similar mass transfers or mergers, occupy a…

We have constructed the Spectral Energy Distributions (SEDs) of a sample of Blue Straggler Stars (BSSs) in the core of the globular cluster 47 Tucanae, taking advantage of the large set of high resolution images, ranging from the…

We present a spectroscopic analysis of HST/STIS and FOS low- and intermediate-resolution spectroscopy of 55 stars (turn-off stars, horizontal branch stars and blue stragglers) in four globular clusters (47 Tucanae, M3, NGC6752, and…

By combining high-resolution (HST-WFPC2) and wide-field ground based (2.2m ESO-WFI) and space (GALEX) observations, we have collected a multi-wavelength photometric data base (ranging from the far UV to the near infrared) of the galactic…

We present a combination of high-resolution Hubble Space Telescope and wide-field ground-based and Galaxy Evolution Explorer data of the Galactic Globular Cluster M10 (NGC6254). By using this large data-set we determined the center of…

In this paper we report on the most significant results from a statistical analysis of the main properties of globular cluster blue straggler stars (BSS) extracted from the HST snapshot database of photometrically homogeneous CMDs (Piotto…

We report the discovery of a variable blue straggler in the core of the globular cluster M5, based on a 12-hour long series of images obtained with the Planetary Camera aboard the Hubble Space Telescope. In addition, we present the light…

We present new Blue Straggler Star (BSS) catalogs in 38 Milky Way globular clusters (GCs) based on multi-passband and multi-epoch treasury survey data from the Hubble Space Telescope. We measure precise astrometry and relative proper…

We present high resolution UVES+VLT spectroscopic observations of 61 stars in the extended blue horizontal branches of the Galactic globular clusters NGC 1904 (M79), NGC 2808, NGC 6093 (M80), and NGC 7078 M15). Our data reveal for the first…

In this paper I present an overview of the main observational properties of a special class of exotic objects (the so-called Blue Straggler Stars, BSSs) in Galactic Globular Clusters (GCs). The BSS specific frequency and their radial…

We have analyzed high-resolution spectra of relatively cool blue stragglers and main sequence turnoff stars in the old open cluster M67 (NGC 2682). We attempt to identify blue stragglers whose spectra are least contaminated by binary…

This chapter presents an overview of the main observational results obtained to date about Blue Straggler Stars (BSSs) in Galactic Globular Clusters (GCs). The BSS specific frequency, radial distribution, chemical composition and rotational…

We use two stellar populations in the globular cluster 47 Tucanae to trace its dynamical history: blue stragglers and low mass main sequence stars. We assumed that the blue stragglers were formed through stellar collisions in all regions of…

The central regions of six Galactic Globular Clusters (GGCs) (M3, M80, M10, M13, M92 and NGC 288) have been imaged using HST-WFPC2 and the ultraviolet (UV) filters (F255W, F336W). The selected sample covers a large range in both central…

We used data from the HST UV Legacy Survey of Galactic Globular Clusters to select the Blue Straggler Star (BSS) population in four intermediate/high density systems (namely NGC 2808, NGC 6388, NGC 6541 and NGC 7078) through a "UV-guided…

We used a proper combination of multiband high-resolution and wide field multi-wavelength observations collected at three different telescopes (HST, LBT and CFHT) to probe Blue Straggler Star (BSS) populations in the globular cluster M53.…

We make use of the Hubble Space Telescope proper-motion catalogs derived by Bellini et al. (2014) to produce the first radial velocity-dispersion profiles sigma(R) for blue straggler stars (BSSs) in Galactic globular clusters (GCs), as well…

The field of the globular cluster M12 (NGC 6218) was monitored between 1995 and 2009 in a search for variable stars. $BV$ light curves were obtained for 36 periodic or likely periodic variables. Thirty-four of these are new detections.…

We have used high resolution WFPC2-HST and wide field ground-based observations to construct a catalog of blue straggler stars (BSS) which spans the entire radial extent of the globular cluster NGC 6752. The BSS sample is the most extensive…

We investigate the effects of changes in the blue straggler formation rate in globular clusters on the blue straggler distribution in the color-magnitude diagram. We find that the blue straggler distribution is highly sensitive to the past…