0 Assigned ID: 3969 ----- Attempting Submission 1 (Fri May 19 13:23:02 GMT 2023) ----- HST Phase I Proposal 3969 successfully submitted. Receipt: # 3969-1 ----- Attempting Submission 2 (Wed May 24 20:16:56 GMT 2023) ----- HST Phase I Proposal 3969 successfully submitted. Receipt: # 3969-2 ----- Attempting Submission 3 (Wed May 24 20:29:36 GMT 2023) ----- We propose to use HST-WFC3 IR grism data to construct a sample of spectroscopically confirmed galaxy pairs and advanced stage mergers in the CANDELS fields over the redshift range 0.4 < z < 2.3 and investigate how star formation and morphology depend on a pair's redshift and separation. We will use photometrically identified galaxy pair candidates over this redshift range and with separations from 1-150 kpc and stellar mass ratios spanning the range 1-10 and identify new pairs that are blended in our photometry. Along with this sample of galaxy pairs, we will also use a sample of advanced stage and post-mergers selected from the CANDELS an COSMOS ACS/WFC3 imaging to piece together the entire merger timeline, from first passage, to coalescence, to merger remnant. We will then measure the star formation rate for each galaxy to look for trends along this merger sequence, relative to a control sample of mass- and redshift-matched isolated galaxies. We will address the question of how much enhancement is seen in the star formation rate of a galaxy during a merger and whether this changes as a function of redshift. How much does this enhancement contribute to the overall decline of the cosmic star formation rate density? The PI (Kartaltepe) is an expert in galaxy morphology, identifying galaxy mergers at high redshift, and has experience analyzing HST observations, including WFC3 grism data. Our team has experience with near-infrared spectroscopy and WFC3 grism data in particular. Kartaltepe and Pforr are both experienced with measuring star formation rates, particularly from the FIR and through SED fitting techniques. Pattnaik, Larson, and Coffin are experienced with extragalactic spectroscopy, redshift measurements, and emission line fitting. Larson is experienced in the analysis of grism spectroscopy. Galaxies 0 Regular false false false false false false SUPPORTED