ULTRAVIOLET MORPHOLOGIES OF GLOBULAR-CLUSTERS OBSERVED WITH THE ULTRAVIOLET IMAGING TELESCOPE

Authors
SMITH EP LANDSMAN WB HILL RS BOHLIN RC CHENG KP HINTZEN P MARAN SP OCONNELL RW ROBERTS MS SMITH AM STECHER TP
Citation
Ep. Smith et al., ULTRAVIOLET MORPHOLOGIES OF GLOBULAR-CLUSTERS OBSERVED WITH THE ULTRAVIOLET IMAGING TELESCOPE, The Astrophysical journal, 418(2), 1993, pp. 850-854
Citations number
28
Categorie Soggetti
Astronomy & Astrophysics
Journal title
The Astrophysical journal → ACNP
ISSN journal
0004637X
Volume
418
Issue
2
Year of publication
1993
Part
1
Pages
850 - 854
Database
ISI
SICI code
0004-637X(1993)418:2<850:UMOGOW>2.0.ZU;2-G
Abstract
We compare the ultraviolet (UV) and visible morphologies of globular c lusters M3, M13, M79, and omega Cen, based on observations with the Ul traviolet Imaging Telescope (UIT) and ground-based telescopes. Global similarities (e.g., core radii) are found, along with other interestin g features. These include a ring (r = 2.2') of UV-bright stars in omeg a Cen and a group of UV-bright objects near the center of M79. We find a color gradient in M79 but in no other cluster. The helium abundance in M79 is Y = 0.21 +/- 0.04, based on UV and visible color-magnitude diagrams.