Blue Stragglers , Young White Dwarfs and UV - excess stars in the core of 47 Tuc

نویسندگان

  • Francesco R. Ferraro
  • Roberto P. Mignani
  • Barbara Paltrinieri
چکیده

We used a set of archived HST/WFPC2 images to probe the stellar population in the core of the nearby Galactic Globular Cluster (GGC) 47 Tuc. From the ultraviolet (UV) Color Magnitude Diagrams (CMDs) obtained for ∼ 4 000 stars detected within the Planetary Camera (PC) field of view we have pinpointed a number of interesting objects: (i) 43 blue stragglers stars (BSSs) including 20

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

A Far - Ultraviolet Survey of 47 Tucanae . II . The Long - Period Cataclysmic Variable AKO 9

We present time-resolved, far-ultraviolet (FUV) spectroscopy and photometry of the 1.1 day eclipsing binary system AKO 9 in the globular cluster 47 Tucanae. AKO 9’s FUV spectrum is blue and exhibits prominent C iv and He ii emission lines. The spectrum broadly resembles that of long-period, cataclysmic variables in the galactic field. Combining our time-resolved FUV data with archival optical p...

متن کامل

A Far - Ultraviolet Survey of 47 Tucanae . II . The Long - Period Cataclysmic Variable AKO 9 1

We present time-resolved, far-ultraviolet (FUV) spectroscopy and photometry of the 1.1 day eclipsing binary system AKO 9 in the globular cluster 47 Tucanae. The FUV spectrum of AKO 9 is blue and exhibits prominent C iv and He ii emission lines. The spectrum broadly resembles that of long-period, cataclysmic variables (CVs) in the galactic field. Combining our time-resolved FUV data with archiva...

متن کامل

Two distinct sequences of blue straggler stars in the globular cluster

Stars in globular clusters are generally believed to have all formed at the same time, early in the Galaxy's history 1. 'Blue stragglers' are stars sufficiently massive 2 that they should have evolved into white dwarfs long ago. Two possible mechanisms have been proposed for their formation: mass transfer between binary companions 3 , and stellar mergers induced by direct collisions between two...

متن کامل

Star cluster ecology IVa: Dissection of an open star cluster—photometry

The evolution of star clusters is studied using N-body simulations in which the evolution of single stars and binaries are taken self-consistently into account. Initial conditions are chosen to represent relatively young Galactic open clusters, such as the Pleiades, Praesepe and the Hyades. The calculations include a realistic mass function, primordial binaries and the external potential of the...

متن کامل

ar X iv : a st ro - p h / 98 04 16 4 v 1 1 6 A pr 1 99 8 The Hot Stars of Old Open Clusters : M 67 , NGC 188 and NGC 6791

We analyze ultraviolet (∼ 1500 Å) images of the old open clusters M67, NGC 188, and NGC 6791 obtained with Ultraviolet Imaging Telescope (UIT) during the second flight of the Astro observatory in March 1995. Twenty stars are detected on the UIT image of M67, including 11 blue stragglers, seven white dwarf candidates, and the yellow giant – white dwarf binary S1040. The ultraviolet photometry of...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2001