NOAO >   Observing Info >   Approved Programs >   2015A-0304

# Program Information for 2015A-0304

PI: Sukyoung K Yi, Yonsei University, yi@yonsei.ac.kr
Address: Astronomy Department, 630, College of Science, Yonsei Univ., 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749 South Korea

CoI: Seulhee Oh, Yonsei University
CoI: Yun-Kyeong Sheen, Universidad de Concepcion

Title: A Spectroscopic Follow-up to Deep Optical Imaging for 3 Abell clusters at z ~ 0.08

Abstract: Galaxy mergers are suspected to play important roles in galaxy formation. In theory, galaxy mergers were more frequent in the early universe and in sparse environments. The fraction of mergers were indeed found to be high ($\sim40\%$) in the field environments when extra-deep ($\mu_r < 28 mag/arcsec^2$) imaging was performed (van Dokkum 2005). To our surprise, the first set of {\em clusters} at z $\sim0.1$ using CTIO Blanco MOSAIC imager and Hydra MOS revealed a post-merger galaxy fraction that was as high as that in the field. We expanded our deep imaging campaign to other clusters using Magellan, CFHT, and du Pont telescopes, but only 8 clusters among 20 with deep imaging have confirmed membership with 90\% completeness. Using the wide field-of- view, multi-object spectrograph of Hydra on WIYN, we request 3 nights to obtain 2000 galaxy spectra of 3 Abell clusters at z $\sim0.08$ to continue our study of galaxy mergers and morphological diversity in cluster environment. Spectroscopic redshift from this observation will be complemented with SDSS which covers 21-46\% of galaxies in the field of clusters proposed here. Since we already have extra-deep images of the clusters, the combination will provide a very useful pseudo-complete catalogue of their member galaxies.

Program Type: Standard/Extragalactic

Scheduled Nights:
Run 1 (2015A):  WIYN/HYDR -- 3n on May 19 - May 21 2015

National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360

 NOAO >   Observing Info >   Approved Programs >   2015A-0304