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The SRG/eROSITA all-sky survey. First X-ray catalogues and data release of the western Galactic hemisphere
Zhang, X.; Haberl, F.; Burwitz, V. +142 more
The eROSITA telescope array aboard the Spektrum Roentgen Gamma (SRG) satellite began surveying the sky in December 2019, with the aim of producing all-sky X-ray source lists and sky maps of an unprecedented depth. Here we present catalogues of both point-like and extended sources using the data acquired in the first six months of survey operations…
An Updated Mass-Radius Analysis of the 2017-2018 NICER Data Set of PSR J0030+0451
Chakrabarty, Deepto; Bogdanov, Slavko; Salmi, Tuomo +12 more
In 2019 the NICER collaboration published the first mass and radius inferred for PSR J0030+0451, thanks to NICER observations, and consequent constraints on the equation of state characterizing dense matter. Two independent analyses found a mass of ~1.3-1.4 M ⊙ and a radius of ~13 km. They also both found that the hot spots were all loc…
A NICER View of the Nearest and Brightest Millisecond Pulsar: PSR J0437–4715
Remillard, Ronald A.; Bogdanov, Slavko; Salmi, Tuomo +17 more
We report Bayesian inference of the mass, radius, and hot X-ray emitting region properties—using data from the Neutron Star Interior Composition ExploreR (NICER)—for the brightest rotation-powered millisecond X-ray pulsar, PSR J0437‑4715. Our modeling is conditional on informative tight priors on mass, distance, and binary inclination obtained fro…
ULTRASAT: A Wide-field Time-domain UV Space Telescope
Mazeh, T.; Gal-Yam, A.; Tal-Or, L. +41 more
The Ultraviolet Transient Astronomy Satellite (ULTRASAT) is scheduled to be launched to geostationary orbit in 2027. It will carry a telescope with an unprecedentedly large field of view (204 deg2) and near-ultraviolet (NUV; 230–290 nm) sensitivity (22.5 mag, 5σ, at 900 s). ULTRASAT will conduct the first wide-field survey of transient …
A lanthanide-rich kilonova in the aftermath of a long gamma-ray burst
Kilpatrick, Charles D.; Lee, Chung-Uk; Im, Myungshin +24 more
Observationally, kilonovae are astrophysical transients powered by the radioactive decay of nuclei heavier than iron, thought to be synthesized in the merger of two compact objects1-4. Over the first few days, the kilonova evolution is dominated by a large number of radioactive isotopes contributing to the heating rate2,5. On…
The Radius of the High-mass Pulsar PSR J0740+6620 with 3.6 yr of NICER Data
Chakrabarty, Deepto; Bogdanov, Slavko; Salmi, Tuomo +14 more
We report an updated analysis of the radius, mass, and heated surface regions of the massive pulsar PSR J0740+6620 using Neutron Star Interior Composition Explorer (NICER) data from 2018 September 21 to 2022 April 21, a substantial increase in data set size compared to previous analyses. Using a tight mass prior from radio-timing measurements and …
SO2, silicate clouds, but no CH4 detected in a warm Neptune
Henning, Thomas; Östlin, Göran; Güdel, Manuel +43 more
WASP-107b is a warm (approximately 740 K) transiting planet with a Neptune-like mass of roughly 30.5 M⊕ and Jupiter-like radius of about 0.94 RJ (refs. 1,2), whose extended atmosphere is eroding3. Previous observations showed evidence for water vapour and a thick, high-altitude condensate layer in the at…
Deep Synoptic Array Science: First FRB and Host Galaxy Catalog
Hallinan, Gregg; Hodges, Mark; Lamb, James W. +19 more
Fast radio bursts (FRBs) are a powerful and mysterious new class of transients that are luminous enough to be detected at cosmological distances. By associating FRBs to host galaxies, we can measure intrinsic and environmental properties that test FRB origin models, in addition to using them as precise probes of distant cosmic gas. The Deep Synopt…
A Systematic Analysis of the X-Ray Emission in Optically Selected Tidal Disruption Events: Observational Evidence for the Unification of the Optically and X-Ray-selected Populations
Cenko, S. Bradley; van Velzen, Sjoert; Gezari, Suvi +4 more
We present a systematic analysis of the X-ray emission of a sample of 17 optically selected, X-ray-detected tidal disruption events (TDEs) discovered between 2014 and 2021. The X-ray light curves show a diverse range of temporal behaviors, with most sources not following the expected power-law decline. The X-ray spectra are mostly extremely soft a…
X-ray eruptions every 22 days from the nucleus of a nearby galaxy
Gendreau, Keith; van Velzen, Sjoert; Gezari, Suvi +15 more
Galactic nuclei showing recurrent phases of activity and quiescence have recently been discovered. Some have recurrence times as short as a few hours to a day and are known as quasi-periodic X-ray eruption (QPE) sources. Others have recurrence times as long as hundreds to a thousand days and are called repeating nuclear transients. Here we present…