GRB 221009A: Discovery of an Exceptionally Rare Nearby and Energetic Gamma-Ray Burst

Kavli Affiliate: Dheeraj R. Pasham | First 5 Authors: Maia A. Williams, Jamie A. Kennea, S. Dichiara, Kohei Kobayashi, Wataru B. Iwakiri | Summary: We report the discovery of the unusually bright long-duration gamma-ray burst (GRB), GRB 221009A, as observed by the Neil Gehrels Swift Observatory (Swift), Monitor of All-sky X-ray Image (MAXI), and Neutron […]


Continue.. GRB 221009A: Discovery of an Exceptionally Rare Nearby and Energetic Gamma-Ray Burst

GRB 221009A: Discovery of an Exceptionally Rare Nearby and Energetic Gamma-Ray Burst

Kavli Affiliate: Dheeraj R. Pasham | First 5 Authors: Maia A. Williams, Jamie A. Kennea, S. Dichiara, Kohei Kobayashi, Wataru B. Iwakiri | Summary: We report the discovery of the unusually bright long-duration gamma-ray burst (GRB), GRB 221009A, as observed by the Neil Gehrels Swift Observatory (Swift), Monitor of All-sky X-ray Image (MAXI), and Neutron […]


Continue.. GRB 221009A: Discovery of an Exceptionally Rare Nearby and Energetic Gamma-Ray Burst

DESI z >~ 5 Quasar Survey. I. A First Sample of 400 New Quasars at z ~ 4.7-6.6

Kavli Affiliate: Risa Wechsler | First 5 Authors: Jinyi Yang, Xiaohui Fan, Ansh Gupta, Adam Myers, Nathalie Palanque-Delabrouille | Summary: We report the first results of a high-redshift ($z$ >~ 5) quasar survey using the Dark Energy Spectroscopic Instrument (DESI). As a DESI secondary target program, this survey is designed to carry out a systematic […]


Continue.. DESI z >~ 5 Quasar Survey. I. A First Sample of 400 New Quasars at z ~ 4.7-6.6

DESI z >~ 5 Quasar Survey. I. A First Sample of 400 New Quasars at z ~ 4.7-6.6

Kavli Affiliate: Risa Wechsler | First 5 Authors: Jinyi Yang, Xiaohui Fan, Ansh Gupta, Adam Myers, Nathalie Palanque-Delabrouille | Summary: We report the first results of a high-redshift ($z$ >~ 5) quasar survey using the Dark Energy Spectroscopic Instrument (DESI). As a DESI secondary target program, this survey is designed to carry out a systematic […]


Continue.. DESI z >~ 5 Quasar Survey. I. A First Sample of 400 New Quasars at z ~ 4.7-6.6

Hubble Constant Measurement from Three Large-Separation Quasars Strongly Lensed by Galaxy Clusters

Kavli Affiliate: Michael D. Gladders | First 5 Authors: Kate Napier, Keren Sharon, Håkon Dahle, Matthew Bayliss, Michael D. Gladders | Summary: Tension between cosmic microwave background-based and distance ladder-based determinations of the Hubble constant ${rm H}_{rm 0}$ motivates pursuit of independent methods that are not subject to the same systematic effects. A promising alternative, […]


Continue.. Hubble Constant Measurement from Three Large-Separation Quasars Strongly Lensed by Galaxy Clusters

Mapping the X-ray variability of GRS1915+105 with machine learning

Kavli Affiliate: Ronald A. Remillard | First 5 Authors: Benjamin J. Ricketts, James F. Steiner, Cecilia Garraffo, Ronald A. Remillard, Daniela Huppenkothen | Summary: Black hole X-ray binary systems (BHBs) contain a close companion star accreting onto a stellar-mass black hole. A typical BHB undergoes transient outbursts during which it exhibits a sequence of long-lived […]


Continue.. Mapping the X-ray variability of GRS1915+105 with machine learning

Cosmic Web Dissection in Fuzzy Dark Matter Cosmologies

Kavli Affiliate: George Efstathiou | First 5 Authors: Tibor Dome, Anastasia Fialkov, Nina Sartorio, Philip Mocz, | Summary: On large cosmological scales, anisotropic gravitational collapse is manifest in the dark cosmic web. Its statistical properties are little known for alternative dark matter models such as fuzzy dark matter (FDM). In this work, we assess for […]


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NICER/NuSTAR Characterization of 4U 1957+11: A Near Maximally Spinning Black Hole Potentially in the Mass Gap

Kavli Affiliate: Ronald A. Remillard | First 5 Authors: Erin Barillier, Victoria Grinberg, David Horn, Michael A. Nowak, Ronald A. Remillard | Summary: 4U 1957+11 is a black hole candidate system that has been in a soft X-ray spectral state since its discovery. We present analyses of recent joint NICER and NuSTAR spectra, which are […]


Continue.. NICER/NuSTAR Characterization of 4U 1957+11: A Near Maximally Spinning Black Hole Potentially in the Mass Gap