The ellipticities of a sample of globular clusters in M31

Abstract

view Abstract Citations (20) References (27) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Ellipticities of a Sample of Globular Clusters in M31 Lupton, Robert H. Abstract I have obtained images for a sample of 18 globular clusters in M31. The mean ellipticity on the sky in the range 7-14 pc (2-4 arcsec) is 0.08 +/- 0.02 and 0.12 +/- 0.01 in the range 14-21 pc (4-6 arcsec), with corresponding true ellipticities of 0.12 and 0.18. The difference between the inner and outer parts is significant at a 99% level. The flattening of the inner parts is statistically indistinguishable from that of the Galactic globular clusters, while the outer parts are flatter than the Galactic clusters at a 99.8% confidence level, and have ellipticities comparable to the LMC clusters of SWB classes I-VII. There is a significant anticorrelation of ellipticity with line strength; such a correlation may in retrospect also be seen in the Galactic globular cluster system. For the M31 data, this anticorrelation is stronger in the inner parts of the galaxy. Publication: The Astronomical Journal Pub Date: May 1989 DOI: 10.1086/115078 Bibcode: 1989AJ.....97.1350L Keywords: Andromeda Galaxy; Ellipticity; Globular Clusters; Galactic Rotation; Metallicity; Signal To Noise Ratios; Astronomy; GALAXIES: INDIVIDUAL; GALAXIES: STELLAR CONTENT; CLUSTERS: GLOBULAR full text sources ADS | data products SIMBAD (21) NED (19)