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Chandra, HST/STIS, NICER, Swift, and TESS Detail the Flare Evolution of the Repeating Nuclear Transient ASASSN -14ko
DOI: 10.3847/1538-4357/acd455 Bibcode: 2023ApJ...951..134P

Holoien, Thomas W. -S.; Vallely, Patrick J.; Auchettl, Katie +9 more

ASASSN-14ko is a nuclear transient at the center of the AGN ESO 253-G003 that undergoes periodic flares. Optical flares were first observed in 2014 by the All-Sky Automated Survey for Supernovae (ASAS-SN) and their peak times are well-modeled with a period of ${115.2}_{-1.2}^{+1.3}$ days and period derivative of -0.0026 ± 0.0006. Here we present A…

2023 The Astrophysical Journal
eHST 26
Statistics of Galactic-scale Quasar Pairs at Cosmic Noon
DOI: 10.3847/1538-4357/aca662 Bibcode: 2023ApJ...943...38S

Shen, Yue; Oguri, Masamune; Kratter, Kaitlin M. +8 more

The statistics of galactic-scale quasar pairs can elucidate our understanding of the dynamical evolution of supermassive black hole (SMBH) pairs, the duty cycles of quasar activity in mergers, or even the nature of dark matter, but they have been challenging to measure at cosmic noon, the prime epoch of massive galaxy and SMBH formation. Here we m…

2023 The Astrophysical Journal
Gaia eHST 26
RELICS: Small-scale Star Formation in Lensed Galaxies at z = 6-10
DOI: 10.3847/1538-4357/aca8a8 Bibcode: 2023ApJ...943....2W

Ravindranath, Swara; Windhorst, Rogier; Bradač, Maruša +13 more

Detailed observations of star-forming galaxies at high redshift are critical to understanding the formation and evolution of the earliest galaxies. Gravitational lensing provides an important boost, allowing observations at physical scales unreachable in unlensed galaxies. We present three lensed galaxies from the RELICS survey at z phot

2023 The Astrophysical Journal
eHST 26
Multi-messenger Model for the Prompt Emission from GRB 221009A
DOI: 10.3847/2041-8213/acb6d7 Bibcode: 2023ApJ...944L..34R

Bošnjak, Željka; Petropoulou, Maria; Rudolph, Annika +1 more

We present a multi-messenger model for the prompt emission from GRB 221009A within the internal shock scenario. We consider the time-dependent evolution of the outflow with its impact on the observed light curve from multiple collisions, as well as the self-consistent generation of the electromagnetic spectrum in synchrotron and inverse Compton-do…

2023 The Astrophysical Journal
INTEGRAL 26
The Sloan Digital Sky Survey Reverberation Mapping Project: The Black Hole Mass-Stellar Mass Relations at 0.2 ≲ z ≲ 0.8
DOI: 10.3847/1538-4357/acddda Bibcode: 2023ApJ...954..173L

Koekemoer, Anton M.; Trump, Jonathan R.; Brandt, W. N. +7 more

We measure the correlation between black hole mass M BH and host stellar mass M * for a sample of 38 broad-line quasars at 0.2 ≲ z ≲ 0.8 (median redshift z med = 0.5). The black hole masses are derived from a dedicated reverberation mapping program for distant quasars, and the stellar masses are derived from two-ba…

2023 The Astrophysical Journal
eHST 26
UV-Optical Disk Reverberation Lags despite a Faint X-Ray Corona in the Active Galactic Nucleus Mrk 335
DOI: 10.3847/1538-4357/acbcd3 Bibcode: 2023ApJ...947...62K

Kaspi, Shai; Fabian, Andrew C.; Komossa, S. +37 more

We present the first results from a 100-day Swift, NICER, and ground-based X-ray-UV-optical reverberation mapping campaign of the Narrow-line Seyfert 1 Mrk 335, when it was in an unprecedented low X-ray flux state. Despite dramatic suppression of the X-ray variability, we still observe UV-optical lags as expected from disk reverberation. Moreover,…

2023 The Astrophysical Journal
XMM-Newton 26
Near-Sun In Situ and Remote-sensing Observations of a Coronal Mass Ejection and its Effect on the Heliospheric Current Sheet
DOI: 10.3847/1538-4357/ace62e Bibcode: 2023ApJ...954..168R

Lario, D.; Bale, S. D.; Raouafi, N. E. +20 more

During the thirteenth encounter of the Parker Solar Probe (PSP) mission, the spacecraft traveled through a topologically complex interplanetary coronal mass ejection (ICME) beginning on 2022 September 5. PSP traversed through the flank and wake of the ICME while observing the event for nearly two days. The Solar Probe ANalyzer and FIELDS instrumen…

2023 The Astrophysical Journal
SolarOrbiter 26
Early Results from GLASS-JWST. XXII. Rest-frame UV-Optical Spectral Properties of Lyα Emitting Galaxies at 3 < z < 6
DOI: 10.3847/2041-8213/acdbce Bibcode: 2023ApJ...952L..14R

Pentericci, Laura; Treu, Tommaso; Scarlata, Claudia +13 more

Lyα emission is possibly the best indirect diagnostic of Lyman continuum (LyC) escape since the conditions that favor the escape of Lyα photons are often the same that allow for the escape of LyC photons. In this work, we present the rest-frame UV-optical spectral characteristics of 11 Lyα emitting galaxies at 3 < z < 6-the redshift range th…

2023 The Astrophysical Journal
eHST JWST 26
CO Emission, Molecular Gas, and Metallicity in Main-sequence Star-forming Galaxies at z ∼ 2.3
DOI: 10.3847/1538-4357/aca46f Bibcode: 2023ApJ...942...24S

Siana, Brian; Shapley, Alice E.; Reddy, Naveen A. +9 more

We present observations of CO(3-2) in 13 main-sequence z = 2.0-2.5 star-forming galaxies at $\mathrm{log}({M}_{* }/{M}_{\odot })=10.2\mbox{--}10.6$ that span a wide range in metallicity (O/H) based on rest-optical spectroscopy. We find that ${L}_{\mathrm{CO}(3-2)}^{{\prime} }$ /SFR decreases with decreasing metallicity, implying that the CO lumino…

2023 The Astrophysical Journal
eHST 26
The Hot Circumgalactic Medium of the Milky Way: New Insights from XMM-Newton Observations
DOI: 10.3847/1538-4357/acd337 Bibcode: 2023ApJ...952...41B

Mathur, Smita; Gupta, Anjali; Das, Sanskriti +2 more

We present XMM-Newton observations around the sight line of Mrk 421. The emission spectrum of the Milky Way (MW) circumgalactic medium (CGM) shows that a two-phase model is a better fit to the data compared to a single-phase model; in addition to the warm-hot virial phase at log (T/K) = 6.30 ± 0.02, a hot super-virial phase at log (T/K) = ${6.88}_…

2023 The Astrophysical Journal
XMM-Newton 25