Use of Cross-Correlation Function to Study Formation Mechanism of Massive Elliptical Galaxies

作者:De Tuli*; Chattopadhyay Tanuka; Chattopadhyay Asis Kumar
来源:Publications of the Astronomical Society of Australia, 2014, 31: e047.
DOI:10.1017/pasa.2014.42

摘要

Spatial clustering nature of galaxies has been studied previously through auto correlation function. The same type of cross-correlation function has been used in the present work to investigate parametric clustering nature of galaxies with respect to masses and sizes of galaxies. Here, formation and evolution of several components of nearby massive early type galaxies (M-* %26gt;= 1.3 x 10(11)M(circle dot)) have been envisaged through cross-correlations, in the mass-size parametric plane, with high redshift (0.2 %26lt;= z %26lt;= 7) ETGs. It is found that the inner most components of nearby ETGs have significant correlation (similar to 0.5 +/- (0.02-0.07)) with ETGs in the highest redshift range (2 %26lt;= z %26lt;= 7) called %26apos;red nuggets%26apos; whereas intermediate components are highly correlated (similar to 0.65 +/- (0.03-0.07)) with ETGs in the redshift range 0.5 %26lt;= z %26lt;= 0.75. The outermost part has no correlation in any range, suggesting a scenario through in situ accretion. The above formation scenario is consistent with the previous results obtained for NGC5128 and to some extent for nearby elliptical galaxies after considering a sample of ETGs at high redshift with stellar masses greater than or equal to 10(8.73)M(circle dot). So the present work indicates a three phase formation instead of two as discussed in previous works.

  • 出版日期2014-11-20