collaborators

21 papers

astro-ph.SR2026

Luminous Red Novae as shock-powered transients I: Electron-scattering wings and deviations from Case B

Albert Sneppen, Kenta Hotokezaka, Christopher M. Irwin

Luminous red novae (LRNe) are a class of optical transients resulting from the mergers of binary stars or common envelope events. The population displays heterogeneous light curves…

astro-ph.GA2026

The metallicities of little red dot host galaxies: LRDs are metal poor, but not pristine

G. P. Nikopoulos, D. Watson, C. L. Pollock +4

Little Red Dots (LRDs) are a population of high-z sources discovered by JWST whose compactness, broad permitted lines, strong absorption features, continuum shapes and luminosities…

astro-ph.GA2026

TBD LBD: The nature of `little blue dots'

Albert Sneppen, Darach Watson, James H. Matthews +1

Previous Sirocco radiative-transfer models of gas-cocooned AGN predicted lower-column counterparts to little red dots (LRDs): compact, X-ray-weak sources with bluer continuum slope…

astro-ph.GA2026

Quenching of X-ray emission in little red dots by both Compton-thick gas and high accretion rates

Albert Sneppen, Darach Watson, James H. Matthews +1

Little red dots (LRDs) are candidate high-redshift supermassive black holes accreting in dense gas. They remain undetected in X-rays. In previous work, we provided the first quanti…

astro-ph.GA2026

Paschen Jumps in Little Red Dots: Evidence for Nebular Continua

Albert Sneppen, James H. Matthews, Darach Watson +6

''Little Red Dots'' (LRDs) are broad-line sources at high redshift, initially identified by their compact morphologies, red colours and prominent Balmer breaks. The origin of their…

astro-ph.HE2026

Strontium and helium in the kilonova AT2017gfo: Origin of the 1μm feature constrained via NLTE calculations

Aayush Arya, Rasmus Damgaard, Albert Sneppen +4

Mergers of neutron stars are believed to be one of the primary sites for the synthesis of the universe's heavy elements via the rapid neutron capture process. AT2017gfo, the kilono…