JWST spectra of SN 2022acko reveal CO masses of 1.55e-4 and 2.47e-4 solar masses, IME velocities ~300 km/s vs ~100 km/s for H/He/IGEs suggesting bipolar outflow, and substantially less molecule formation than higher-mass Type II SNe.
A Survey of z>5.7 Quasars in the Sloan Digital Sky Survey II: Discovery of Three Additional Quasars at z>6
4 Pith papers cite this work. Polarity classification is still indexing.
abstract
We present the discovery of three new quasars at z>6 in 1300 deg^2 of SDSS imaging data, J114816.64+525150.3 (z=6.43), J104845.05+463718.3 (z=6.23) and J163033.90+401209.6 (z=6.05). The first two objects have weak Ly alpha emission lines; their redshifts are determined from the positions of the Lyman break. They are only accurate to 0.05 and could be affected by the presence of broad absorption line systems. The last object has a Ly alpha strength more typical of lower redshift quasars. Based on a sample of six quasars at z>5.7 that cover 2870 deg^2 presented in this paper and in Paper I, we estimate the comoving density of luminous quasars at z 6 and M_{1450} < -26.8 to be (8 +/- 3)x10^{-10} Mpc^{-3} (for H_0 = 50 km/s/Mpc, Omega = 1). HST imaging of two z>5.7 quasars and high-resolution ground-based images (seeing 0.4'') of three additional z>5.7 quasars show that none of them is gravitationally lensed. The luminosity distribution of the high-redshfit quasar sample suggests the bright end slope of the quasar luminosity function at z 6 is shallower than Psi L^{-3.5} (2-sigma), consistent with the absence of strongly lensed objects.
citation-role summary
citation-polarity summary
verdicts
UNVERDICTED 4roles
background 1polarities
background 1representative citing papers
Machine learning on simulated images identifies that flux eruption events cause more diffuse, polarized, lower-flux millimeter emission with decreased Q-U loop rotation rate, achieving ~80% accuracy with random forests on summary statistics.
Cosmological hydrodynamical simulations predict that UV diversity in Little Red Dots encodes direct-collapse black hole ages via a rapid transition from BH- to stellar-dominated emission after ~30 Myr.
The paper reviews dust production, destruction and growth processes in galaxies, compiles literature data on comoving dust mass density, presents evidence for and against interstellar dust growth, and identifies the high-redshift dust budget as needing further study.
citing papers explorer
-
JWST Medium-Resolution Infrared Spectroscopy of SN 2022acko: Tracing Molecule Formation in the Nebular Phase
JWST spectra of SN 2022acko reveal CO masses of 1.55e-4 and 2.47e-4 solar masses, IME velocities ~300 km/s vs ~100 km/s for H/He/IGEs suggesting bipolar outflow, and substantially less molecule formation than higher-mass Type II SNe.
-
Identifying Observational Signatures of Flux Eruption Events in Supermassive Black Hole Accretion Flows with Machine Learning
Machine learning on simulated images identifies that flux eruption events cause more diffuse, polarized, lower-flux millimeter emission with decreased Q-U loop rotation rate, achieving ~80% accuracy with random forests on summary statistics.