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The Power of the Rings: The GRB 221009A Soft X-Ray Emission from Its Dust-scattering Halo
Pintore, Fabio; Mereghetti, Sandro; Esposito, Paolo +11 more
GRB 221009A is the brightest gamma-ray burst (GRB) ever detected that has occurred at low Galactic latitude. Owing to this exceptional combination, its prompt X-ray emission could be detected for weeks in the form of expanding X-ray rings produced by scattering in Galactic dust clouds. We report on the analysis of 20 rings, generated by dust at di…
Carbon dredge-up required to explain the Gaia white dwarf colour-magnitude bifurcation
Blouin, Simon; Tremblay, Pier-Emmanuel; Bédard, Antoine
The Gaia colour-magnitude diagram reveals a striking separation between hydrogen-atmosphere white dwarfs and their helium-atmosphere counterparts throughout a significant portion of the white dwarf cooling track. However, pure-helium atmospheres have Gaia magnitudes that are too close to the pure-hydrogen case to explain this bifurcation. To repro…
Interrogating Solar Flare Loop Models with IRIS Observations 2: Plasma Properties, Energy Transport, and Future Directions
Kerr, Graham S.
During solar flares a tremendous amount of magnetic energy is released and transported through the Sun's atmosphere and out into the heliosphere. Despite over a century of study, many unresolved questions surrounding solar flares are still present. Among those are how does the solar plasma respond to flare energy deposition, and what are the impor…
Water-rich Disks around Late M Stars Unveiled: Exploring the Remarkable Case of Sz 114
Zhang, Ke; Pascucci, Ilaria; Banzatti, Andrea +18 more
We present an analysis of the JDISCS JWST/MIRI-MRS spectrum of Sz 114, an accreting M5 star surrounded by a large dust disk with a shallow gap at ~39 au. The spectrum is molecule-rich; we report the detection of water, CO, CO2, HCN, C2H2, and H2. The only identified atomic/ionic transition is from [Ne II…
The demographics of obscured AGN from X-ray spectroscopy guided by multiwavelength information
Aird, James; Lapi, Andrea; Carrera, Francisco J. +10 more
A complete census of active galactic nuclei (AGNs) is a prerequisite for understanding the growth of supermassive black holes across cosmic time. A significant challenge towards this goal is the whereabouts of heavily obscured AGN that remain uncertain. This paper sets new constraints on the demographics of this population by developing a methodol…
The mystery in Gaia DR3 triples: occurrence rates, orientations, and eccentricities of wide tertiaries around close binaries
Hwang, Hsiang-Chih
The formation of close binaries has been an open question for decades. A large fraction of close binaries are in triple systems, suggesting that their formation may be associated with the Kozai-Lidov mechanism. However, this picture remains under debate because the configurations of many observed triples are unlikely to trigger the Kozai-Lidov mec…
X-SHYNE: X-shooter spectra of young exoplanet analogs. I. A medium-resolution 0.65-2.5 µm one-shot spectrum of VHS 1256−1257 b
Bayo, A.; Tremblin, P.; Lagrange, A. -M. +13 more
We present simultaneous 0.65-2.5 µm medium resolution (3300 ≤ Rλ ≤ 8100) VLT/X-shooter spectra of the relatively young (150-300 Myr) low-mass (19 ± 5MJup) L-T transition object VHS 1256−1257 b, a known spectroscopic analog of HR8799d. The companion is a prime target for the JWST Early Release Science (ERS) and one of th…
Precise physical conditions for the warm gas outflows in the nearby active galaxy IC 5063
Morganti, Raffaella; Oosterloo, Tom; Holden, Luke R. +1 more
Active galactic nucleus (AGN)-driven outflows are now routinely used in models of galaxy evolution as a feedback mechanism; however, many of their properties remain highly uncertain. Perhaps the greatest source of uncertainty is the electron density of the outflowing gas, which directly affects derived kinetic powers and mass outflow rates. Here w…
High-energy Neutrinos from the Inner Circumnuclear Region of NGC 1068
Gallagher, John S.; Lopez Rodriguez, Enrique; Halzen, Francis +1 more
High-energy neutrinos are detected by the IceCube Observatory in the direction of NGC 1068, the archetypical type II Seyfert galaxy. The neutrino flux, surprisingly, is more than an order of magnitude higher than the γ-ray upper limits at measured TeV energy, posing tight constraints on the physical conditions of a neutrino production site. We rep…
The Masses of a Sample of Radial-velocity Exoplanets with Astrometric Measurements
Zhao, Gang; Wang, Wei; Xiao, Guang-Yao +6 more
Being one of the most fundamental physical parameter of astronomical objects, mass plays a vital role in the study of exoplanets, including their temperature structure, chemical composition, formation, and evolution. However, nearly a quarter of the known confirmed exoplanets lack measurements of their masses. This is particularly severe for those…