AstroSat Study of the Globular Cluster NGC 2298: Probable Evolutionary Scenarios of Hot Horizontal Branch Stars

  title={AstroSat Study of the Globular Cluster NGC 2298: Probable Evolutionary Scenarios of Hot Horizontal Branch Stars},
  author={Sharmila Rani and Gajendra Pandey and Annapurni Subramaniam and Chul Chung and Snehalata Sahu and N. Kameswara Rao},
  journal={The Astrophysical Journal},
We present the far-UV (FUV) photometry of images acquired with UVIT on AstroSat to probe the horizontal branch (HB) population of the Galactic globular cluster NGC 2298. UV-optical color–magnitude diagrams (CMDs) are constructed for member stars in combination with Hubble Space Telescope UV Globular Cluster Survey data for the central region and Gaia and ground-based photometric data for the outer region. A blue HB (BHB) sequence with a spread and four hot HB stars are detected in all FUV… 


Hot UV-bright stars of galactic globular clusters
Context. We have performed a census of the UV-bright population in 78 globular clusters using wide-field UV telescopes. This population includes a variety of phases of post-horizontal branch (HB)
The peculiar horizontal branch of NGC 2808
We present an accurate analysis of the peculiar horizontal branch (HB) of the massive Galactic globular cluster NGC 2808, based on high-resolution far-UV and optical images of the central region of
The hot horizontal-branch stars in ω Centauri
Context. UV observations of some massive globular clusters have revealed a significant population of stars hotter and fainter than the hot end of the horizontal branch (HB), the so-called blue hook
Helium enhanced stars and multiple populations along the horizontal branch of NGC 2808: direct spectroscopic measurements
We present an abundance analysis of 96 horizontal branch (HB) stars in NGC 2808, a globular cluster exhibiting a complex multiple stellar population p attern. These stars are distributed in different
Horizontal Branch Stars in the Core of M32
We present the deepest near-UV image of M32 to date, which for the first time resolves hot horizontal branch (HB) stars in an elliptical galaxy. Given the near-solar metallicity of M32, much larger
The Horizontal Branch population of NGC 1851 as revealed by the Ultra-violet Imaging Telescope (UVIT)
We present the UV photometry of the globular cluster NGC 1851 using images acquired with the Ultra-violet Imaging Telescope (UVIT) onboard the ASTROSAT satellite. PSF-fitting photometric data derived
Hubble Space Telescope Observations of New Horizontal-Branch Structures in the Globular Cluster ω Centauri*
The globular cluster ω Centauri contains the largest known population of very hot horizontal-branch (HB) stars. We have used the Hubble Space Telescope to obtain a far-UV/optical color-magnitude
Spectroscopic and photometric evidence of two stellar populations in the Galactic globular cluster NGC 6121 (M 4)
Aims. We present abundance analysis based on high resolution spectra of 105 isolated red giant branch (RGB) stars in the Galactic Globular Cluster NGC 6121 (M 4). Our aim is to study its star
The Dearth of UV-Bright Stars in M32: Implications for Stellar Evolution Theory*
Using the Space Telescope Imaging Spectrograph on the Hubble Space Telescope, we have obtained deep, far-ultraviolet images of the compact elliptical galaxy M32. When combined with earlier
Discovery of Blue Hook Stars in the Massive Globular Cluster M54
We present BV photometry centered on the globular cluster M54 (NGC 6715). The color-magnitude diagram clearly shows a blue horizontal branch extending anomalously beyond the zero-age