Feedback-regulated Super Massive Black Hole Seed Formation

The nature of the seeds of high-redshift supermassive black holes (SMBHs) is a key question in cosmology. Direct collapse black holes (DCBH) that form in pristine, atomic-line cooling halos, illuminated by a Lyman-Werner (LW) UV flux exceeding a critical threshold Jcrit represent an attractive possibility. We investigate when and where these conditions are met during cosmic evolution. For the LW intensity, JLW, we account for departures from the background value in close proximity to star form-ing galaxies. For the pristine halo fraction, we account for both (i) supernova driven outflows, and (ii) the inherent pollution from progenitor halos. We estimate the abun-dance of DCBH formation sites, nDCBH(z), and find that it increases with cosmic time from nDCBH(z = 20) ∼ 10−12 − 10−7 cMpc−3 to nDCBH(z = 10) ∼ 10−10 − 10−5 cMpc−3. Our analysis shows the possible importance of galactic winds, which can suppress the predicted nDCBH by several orders of magnitude, and cause DCBH for-mation to preferentially occur around the UV-brightest (MUV ∼ −21±1) star forming galaxies. Our analysis further highlights the dependence of these predictions on (i) the escape fraction of LW photons, (ii) Jcrit, and (iii) the galactic outflow prescription