Paper
The Luminosity Function and Clustering of H$α$ Emitting Galaxies at $z\approx4-6$ from a Complete NIRCam Grism Redshift Survey
Authors
Xiaojing Lin, Eiichi Egami, Fengwu Sun, Haowen Zhang, Xiaohui Fan, Jakob M. Helton, Feige Wang, Andrew J. Bunker, Zheng Cai, Daniel J. Eisenstein, Daniel T. Jaffe, Zhiyuan Ji, Xiangyu Jin, Maria Anne Pudoka, Sandro Tacchella, Wei Leong Tee, Pierluigi Rinaldi, Brant Robertson, Yang Sun, Christopher N. A. Willmer, Chris Willott, Junyu Zhang, Yongda Zhu
Abstract
We study the luminosity function (LF) and clustering properties of 888 H emitters (HAEs) at in the GOODS-N field. The sample, built from JWST CONGRESS and FRESCO NIRCam grism surveys using a novel redshift assignment algorithm, spans 62 arcmin and reaches . We identify two prominent filamentary protoclusters at and , hosting 98 and 144 HAEs, respectively. The observed H LFs show similar shallow faint-end slopes for both protocluster and field galaxies at , and for the protocluster at ( to ). In contrast, the field LF at is much steeper (), suggesting that protocluster galaxies at are more evolved, resembling those at . The observed star formation rate density from H, integrated down to 0.45 , is and at and , with protoclusters contributing 25% and 55%, respectively. This implies that a large fraction of star formation at occurs in protoclusters. We conduct the first star-formation-rate-limited 3D clustering analysis at . We find the filamentary protocluster geometry flattens the power-law shape of the HAE auto-correlation functions, with slopes much shallower than typically assumed. The auto-correlation function of field HAEs have correlation lengths of at and at . Comparing the observed correlation functions with the UniverseMachine simulation, we infer the dark matter (sub-)halo masses of HAEs to be at , with a scatter of 0.4 dex.