Suppressed star formation by a merging cluster system

July 2017 • 2017MNRAS.469L..20M

Authors • Mansheim, A. S. • Lemaux, B. C. • Tomczak, A. R. • Lubin, L. M. • Rumbaugh, N. • Wu, P. -F. • Gal, R. R. • Shen, L. • Dawson, W. A. • Squires, G. K.

Abstract • We examine the effects of an impending cluster merger on galaxies in the large-scale structure (LSS) RX J0910 at z =1.105. Using multiwavelength data, including 102 spectral members drawn from the Observations of Redshift Evolution in Large Scale Environments (ORELSE) survey and precise photometric redshifts, we calculate star formation rates and map the specific star formation rate density of the LSS galaxies. These analyses along with an investigation of the colour-magnitude properties of LSS galaxies indicate lower levels of star formation activity in the region between the merging clusters relative to the outskirts of the system. We suggest that gravitational tidal forces due to the potential of the merging haloes may be the physical mechanism responsible for the observed suppression of star formation in galaxies caught between the merging clusters.


IPAC Authors


Gordon Squires

Senior Scientist