# A search for high-redshift direct collapse black hole candidates in the PEARLS north ecliptic pole field

**Authors:** Armin Nabizadeh, Erik Zackrisson, Fabio Pacucci, Peter W. Maksym, Weihui Li, Francesca Civano, Seth H. Cohen, Jordan C. J. D'Silva, Anton M. Koekemoer, Jake Summers, Rogier A. Windhorst, Nathan Adams, Christopher J. Conselice, Dan Coe, Simon P. Driver, Brenda Frye, Norman A. Grogin, Rolf A. Jansen, Madeline A. Marshall, Mario Nonino  
**arXiv:** [2308.07260](https://arxiv.org/abs/2308.07260)  
**Date:** 2023-08-14  
**Summary page:** https://www.summarizepaper.com/en/paper/2308.07260v1/

## Key points

- Direct-collapse black holes (DCBHs) are believed to be progenitors of supermassive black holes observed in quasars at high redshifts.
- DCBHs form in HI-cooling halos in the early Universe and have masses ranging from $10^4$ to $10^5 M_\odot$.
- Surrounding gas accretion can make DCBH seeds bright enough for detection with the James Webb Space Telescope (JWST) up to redshifts of about 15.
- A search for high-redshift DCBH candidates was conducted in the North Ecliptic Pole Time Domain Field (NEP) using JWST cycle-1 "PEARLS" survey data.
- Three objects consistent with DCBH models were identified, but distinguishing them from other sources remains challenging across different redshifts.
- Follow-up spectroscopy is necessary to determine the true nature of these objects.
- Two of the identified DCBH candidates are suitable for practical follow-up spectroscopy.
- The study sets a conservative upper limit on the comoving density of host halos capable of hosting similar DCBHs at $z\approx 6$-13, which is approximately $7\times 10^{-4}$ cMpc$^{-3}$.
- The study provides valuable insights into searching for high-redshift DCBH candidates and highlights challenges in distinguishing them from other astrophysical sources.

## Summary

. Direct-collapse black holes (DCBHs) are believed to be the progenitors of supermassive black holes that power quasars observed at high redshifts. These DCBHs form in HI-cooling halos in the early Universe and have masses ranging from $10^4$ to $10^5 M_\odot$. The efficient accretion of surrounding gas onto these DCBH seeds can make them bright enough for detection with the James Webb Space Telescope (JWST) up to redshifts of about 15. In this study, the authors conducted a search for high-redshift DCBH candidates in the North Ecliptic Pole Time Domain Field (NEP) using data from the JWST cycle-1 "Prime Extragalactic Areas for Reionization and Lensing Science" (PEARLS) survey. They analyzed a region covering 34 arcmin$^{2}$ using 8 NIRCam filters, reaching a maximum depth of approximately 29 AB mag. The researchers identified three objects with spectral energy distributions consistent with DCBH models proposed by Pacucci et al. (2016). However, they noted that even with data from multiple filters, distinguishing these objects from dusty galaxies and obscured active galactic nuclei remains challenging across a wide range of redshifts. Follow-up spectroscopy would be necessary to determine the true nature of these objects. Two of the identified DCBH candidates are bright enough for practical follow-up spectroscopy. Based on their sample and assumptions about the typical duration of the steep-slope state of DCBHs, the authors set a conservative upper limit on the comoving density of host halos capable of hosting similar DCBHs at $z\approx 6$-13, which is approximately $7\times 10^{-4}$ cMpc$^{-3}$. Overall, this study provides valuable insights into the search for high-redshift DCBH candidates and highlights the challenges in distinguishing them from other astrophysical sources. The results contribute to our understanding of the formation and evolution of supermassive black holes in the early Universe.