Search Publications
Missions
Journals
Publication Years
The eROSITA Final Equatorial-Depth Survey (eFEDS). The Stellar Counterparts of eROSITA sources identified by machine learning and Bayesian algorithms
Schmitt, J. H. M. M.; Salvato, M.; Czesla, S. +3 more
Stars are ubiquitous X-ray emitters and will be a substantial fraction of the X-ray sources detected in the on-going all-sky survey performed by the eROSITA instrument aboard the Spectrum Roentgen Gamma (SRG) observatory. We use the X-ray sources in the eROSITA Final Equatorial-Depth Survey (eFEDS) field observed during the SRG performance verific…
Systematic Korea Microlensing Telescope Network planetary anomaly search - III. One wide-orbit planet and two stellar binaries
Han, Cheongho; Udalski, Andrzej; Lee, Chung-Uk +36 more
Only a few wide-orbit planets around old stars have been detected, which limits our statistical understanding of this planet population. Following the systematic search for planetary anomalies in microlensing events found by the Korea Microlensing Telescope Network, we present the discovery and analysis of three events that were initially thought …
511 keV line constraints on feebly interacting particles from supernovae
Calore, Francesca; Carenza, Pierluca; Giannotti, Maurizio +4 more
Feebly interacting particles with masses with O (10 - 100 ) MeV can be copiously produced by core-collapse supernovae (SNe). In this paper we consider the case of MeV-ish sterile neutrinos and dark photons mixed with ordinary neutrinos and photons, respectively. Furthermore, both sterile neutrinos and dark photons may decay into positrons on their…
Diffuse Galactic emission spectrum between 0.5 and 8.0 MeV
Calore, Francesca; Siegert, Thomas; Serpico, Pasquale D. +2 more
The last measurement of the diffuse emission spectrum of the Milky Way in the megaelectronvolt (MeV) photon energy range was performed by CGRO/COMPTEL more than 20 yr ago. We report a new analysis with the spectrometer SPI aboard INTEGRAL in the band 0.5-8.0 MeV, finally superseding the signal-to-noise ratio (S/N) of the historic observations. Thi…
Discovery of a thin lithium plateau among metal-poor red giant branch stars
Salaris, M.; Bonifacio, P.; Spite, M. +5 more
The surface lithium abundance, A(Li), of warm metal-poor dwarf stars exhibits a narrow plateau down to [Fe/H] ~ −2.8 dex, while at lower metallicities the average value drops by 0.3 dex with a significant star-by-star scatter (called `lithium meltdown'). This behaviour is in conflict with predictions of standard stellar evolution models calculated…
Observations of the initial formation and evolution of spiral galaxies at 1 < z < 3 in the CANDELS fields
Conselice, Christopher J.; Simmons, Brooke; Masters, Karen +4 more
Many aspects concerning the formation of spiral and disc galaxies remain unresolved, despite their discovery and detailed study over the past 150 yr. As such, we present the results of an observational search for proto-spiral galaxies and their earliest formation, including the discovery of a significant population of spiral-like and clumpy galaxi…
TOI-2257 b: A highly eccentric long-period sub-Neptune transiting a nearby M dwarf
Bouchy, F.; Queloz, D.; Stern, D. +64 more
Context. Thanks to the relative ease of finding and characterizing small planets around M-dwarf stars, these objects have become cornerstones in the field of exoplanet studies. The current paucity of planets in long-period orbits around M dwarfs makes such objects particularly compelling as they provide clues about the formation and evolution of t…
The Metallicity and Distance of NGC 2403 from Blue Supergiants
Bresolin, Fabio; Kudritzki, Rolf-Peter; Urbaneja, Miguel A.
We present the first quantitative spectral analysis of blue supergiant stars in the nearby galaxy NGC 2403. Out of a sample of 47 targets observed with the LRIS spectrograph at the Keck I telescope we have extracted 16 B- and A-type supergiants for which we have data of sufficient quality to carry out a comparison with model spectra of evolved mas…
The Eel Pulsar Wind Nebula: A PeVatron-candidate Origin for HAWC J1826-128 and HESS J1826-130
Woo, Jooyun; An, Hongjun; Gelfand, Joseph D. +8 more
HAWC J1826-128 is one of the brightest Galactic TeV γ-ray sources detected by the High Altitude Water Cherenkov (HAWC) observatory, with photon energies extending up to nearly ~100 TeV. This HAWC source spatially coincides with the H.E.S.S. TeV source HESS J1826-130 and the "Eel" pulsar wind nebula (PWN), which is associated with the GeV pulsar PS…
Compton-thick AGN in the NuSTAR Era. VIII. A joint NuSTAR-XMM-Newton Monitoring of the Changing-look Compton-thick AGN NGC 1358
Pozzi, F.; Buchner, J.; Feltre, A. +18 more
We present the multi-epoch monitoring with NuSTAR and XMM-Newton of NGC 1358, a nearby Seyfert 2 galaxy whose properties made it a promising candidate X-ray changing-look active galactic nucleus (AGN), i.e., a source whose column density could transition from its 2017 Compton-thick (having LOS hydrogen column density N H,LOS > 10