Galaxy Merger Fractions in Two Clusters at z 2 Using the Hubble Space Telescope Academic Article uri icon

abstract

  • Abstract We measure the fraction of galaxygalaxy mergers in two clusters at z2 using imaging and grism observations from the Hubble Space Telescope. The two galaxy cluster candidates were originally identified as overdensities of objects using deep mid-infrared imaging and observations from the Spitzer Space Telescope, and were subsequently followed up with HST/WFC3 imaging and grism observations. We identify galaxygalaxy merger candidates using high-resolution imaging with the WFC3 in the F105W, F125W, and F160W bands. Coarse redshifts for the same objects are obtained with grism observations in G102 for the z1.6 cluster (IRC0222A) and G141 for the z2 cluster (IRC0222B). Using visual classifications as well as a variety of selection techniques, we measure merger fractions of in IRC0222A and in IRC0222B. In comparison, we measure a merger fraction of for field galaxies at z2. Our study indicates that the galaxygalaxy merger fraction in clusters at z2 is enhanced compared to the field population, but note that more cluster measurements at this epoch are needed to confirm our findings.

published proceedings

  • ASTROPHYSICAL JOURNAL

altmetric score

  • 7.58

author list (cited authors)

  • Watson, C., Tran, K., Tomczak, A., Alcorn, L., Salazar, I. V., Gupta, A., ... Willmer, C.

citation count

  • 22

complete list of authors

  • Watson, Courtney||Tran, Kim-Vy||Tomczak, Adam||Alcorn, Leo||Salazar, Irene V||Gupta, Anshu||Momcheva, Ivelina||Papovich, Casey||van Dokkum, Pieter||Brammer, Gabriel||Lotz, Jennifer||Willmer, Christopher NA

publication date

  • March 2019