What does SILVERRUSH galaxy clustering reveal about reionization and early host haloes?

The SILVERRUSH survey measures clustering for roughly two thousand Lyman-alpha emitters near redshifts six and seven.

Systematic Identification of LAEs for Visible Exploration and Reionization Research Using Subaru HSC (SILVERRUSH). I. Program strategy and clustering properties of ~2000 Lya emitters at z = 6-7 over the 0.3-0.5 Gpc2 survey area

Systematic Identification of LAEs for Visible Exploration and Reionization Research Using Subaru HSC (SILVERRUSH). I. Program strategy and clustering properties of ~2000 Lya emitters at z = 6-7 over the 0.3-0.5 Gpc2 survey area. Ouchi, Masami; Harikane, Yuichi; Shibuya, Takatoshi; Shimasaku, Kazuhiro; Taniguchi, Yoshiaki; Konno, Akira; Kobayashi, Masakazu; Kajisawa, Masaru; Nagao, Tohru; Ono, Yoshiaki; Inoue, Akio K.; Umemura, Masayuki; Mori, Masao, et al., Publications of the Astronomical Society of Japan, 70, 13O (2018).

arXiv:1704.07455

Approach

Subaru/HSC narrowband samples at redshifts 5.7 and 6.6 are analysed with angular correlation functions, reionization models and halo occupation models.

Main result

The measured clustering evolves weakly between the samples. Model comparisons constrain neutral hydrogen and indicate relatively low-mass host haloes for luminous emitters.

Scientific implications

Clustering links the observed galaxy population with both dark matter structure and the patchy ionization of the early intergalactic medium.

Scope and limitations

Neutral fractions and halo masses are model-dependent inferences. Reionization itself can alter the clustering signal and bias host-halo estimates.