Related papers: Little Red Dots as Direct-collapse Black Hole Nurs…
JWST reveals numerous high-z galaxies and Supermassive Black Holes (SMBHs), suggesting that stars and SMBH seeds formation at $z \gtrsim 10$ may be more efficient than previously derived. One popular SMBH seed scenario is the Direct…
The James Webb Space Telescope (JWST) has unveiled numerous massive black holes (BHs) in faint, broad-line active galactic nuclei (AGNs). The discovery highlights the presence of dust-reddened AGN populations, referred to as "little red…
The discovery of Little Red Dots (LRDs) -- a population of compact, high-redshift, dust-reddened galaxies -- is one of the most surprising results from JWST. However, the nature of LRDs is still debated: does the near-infrared emission…
As an unprecedented large population in the early universe, the JWST-discovered little red dots (LRDs) have garnered much attention for formation of massive black holes and galaxies, but their nature remains a mystery. The LRDs appearing as…
The birth of seeds of massive black holes (BHs) and nascent galaxies at cosmic dawn takes place in dense gaseous environments, which play a crucial role in shaping their coevolution and radiation spectra. We investigate gas accretion during…
Little Red Dots, discovered by the James Webb Space Telescope, are hypothesized to be active galactic nuclei containing a supermassive black hole, possibly surrounded by a dense stellar cluster, large amounts of gas, and likely by a…
It has been proposed that the first, intermediate-mass ($\approx 10^{5-6}~M_\odot$) black holes might form through direct collapse of unpolluted gas in atomic-cooling halos exposed to a strong Lyman-Werner (LW) or near-infrared (NIR)…
I hypothesize a physical explanation for the "Little Red Dots" (LRDs) discovered by the James Webb Space Telescope (JWST). The first star formation in the universe occurs in dense clusters, some of which may undergo runaway collapse and…
Recent observations by the James Webb Space Telescope have uncovered a population of compact, red object ($z\sim 4\text{--}7$) known as little red dots (LRDs). The presence of broad Balmer emission lines indicates active galactic nuclei…
Recent discoveries of faint active galactic nuclei (AGN) at the redshift frontier have revealed a plethora of broad \Halpha emitters with optically red continua, named Little Red Dots (LRDs), which comprise 15-30\% of the high redshift…
Recent James Webb Space Telescope observations have revealed a peculiar class of galaxies at redshifts $z \gtrsim 6$, characterized by extremely high central stellar densities and overmassive central supermassive black holes (SMBHs),…
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…
The central engines of Little Red Dots (LRDs) may be ``black hole stars" (BH*s), early stages of black hole growth characterized by dense gas envelopes. So far, the most direct evidence for BH*s comes from a handful of sources where the…
We explore the observational implications of a model in which primordial black holes (PBHs) with a broad birth mass function ranging in mass from a fraction of a solar mass to $\sim$10$^6$ M$_{\odot}$, consistent with current observational…
The James Webb Space Telescope (JWST) has uncovered many compact galaxies at high redshift with broad hydrogen and helium lines, including the enigmatic population of little red dots (LRDs). The nature of these galaxies is debated and is…
Little Red Dots (LRDs), newly identified compact and dusty galaxies with an unexpectedly high number density observed by JWST, have an unusual "V-shaped" rest-frame UV to near-infrared spectral energy distribution (SED). A group of…
We present a theoretical model in which the recently detected over-massive black holes (OBHs), and possibly Little Red Dots (LRDs), arise during a halo-driven transient phase preceding the established coevolution of supermassive black holes…
We analyze the early growth stage of direct-collapse black holes (DCBHs) with $\sim 10^{5} \ \rm M_\odot$, which are formed by collapse of supermassive stars in atomic-cooling halos at $z \gtrsim 10$. A nuclear accretion disk around a…
We argue that the "Little Red Dots" (LRDs) discovered with the James Webb Space Telescope are quasi-stars in their late stages of evolution. Quasi-stars are hypothetical objects predicted to form following the core collapse of supermassive…
The direct collapse (DC) is a promising mechanism that provides massive seed black holes (BHs) with $\sim 10^{5}~M_{\odot}$ in the early universe. To study a long-term accretion growth of a DCBH thus formed, we perform cosmological…