16 citations · 35 across the 12 of their papers we have counts for
13 papers
Chemical signatures from the first stars embedded in metal-poor gas in galaxies at cosmic dawn
Clara L. Pollock, Kasper E. Heintz, Elka Rusta +15
The first generation of stars formed from pristine, neutral hydrogen gas. The most massive of these exploded as supernovae within a few million years of their birth, producing the…
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…
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…
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…
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…
A hot, nebular-dominated galaxy interacting with a pristine PopIII system uncovered by JWST
Henriette Reumert, Kasper E. Heintz, Clara L. Pollock +6
The discovery of galaxies with extremely strong nebular continuum emission at high redshifts provide novel, unique insights into the conditions under which the first super-massive…
The day-long, repeating GRB 250702BDE / EP250702a: A unique extragalactic transient
Andrew J. Levan, Antonio Martin-Carrillo, Tanmoy Laskar +42
Gamma-ray bursts (GRBs) are singular outbursts of high-energy radiation with durations typically lasting from milliseconds to minutes and, in extreme cases, a few hours. They are a…
The optical constants and grain sizes of interstellar dust measured directly using the dust scattered x-ray halo of GRB 221009A
Albert Sneppen, Darach Watson
X-ray scattering is a powerful probe of the optical constants and grain size distribution of interstellar dust. Bright, transient sources are excellent tools for this, since they f…
Helium as an Indicator of the Neutron-Star Merger Remnant Lifetime and its Potential for Equation of State Constraints
Albert Sneppen, Oliver Just, Andreas Bauswein +9
The time until black hole formation in a binary neutron-star (NS) merger contains invaluable information about the nuclear equation of state (EoS) but has thus far been difficult t…
Helium features are inconsistent with the spectral evolution of the kilonova AT2017gfo
Albert Sneppen, Rasmus Damgaard, Darach Watson +3
The spectral features observed in kilonovae (KNe) reveal the elemental composition and the velocity structures of matter ejected from neutron star mergers. In the spectra of the ki…
Emergence hour-by-hour of -process features in the kilonova AT2017gfo
Albert Sneppen, Darach Watson, Rasmus Damgaard +4
The spectral features in the optical/near-infrared counterparts of neutron star mergers (kilonovae, KNe), evolve dramatically on hour timescales. To examine the spectral evolution…
Kilonova evolution -- the rapid emergence of spectral features
Albert Sneppen, Darach Watson, James H. Gillanders +1
Kilonovae (KNe) are one of the fastest types of optical transients known, cooling rapidly in the first few days following their neutron-star merger origin. We show here that KN spe…
Towards inferring the geometry of kilonovae
Christine E. Collins, Luke J. Shingles, Andreas Bauswein +11
Recent analysis of the kilonova, AT2017gfo, has indicated that this event was highly spherical. This may challenge hydrodynamics simulations of binary neutron star mergers, which u…