Search Publications
Energetic proton back-precipitation onto the solar atmosphere in relation to long-duration gamma-ray flares
Laitinen, T.; Dalla, S.; de Nolfo, G. A. +4 more
Context. Gamma-ray emission during long-duration gamma-ray flare (LDGRF) events is thought to be caused mainly by > 300 MeV protons interacting with the ambient plasma at or near the photosphere. Prolonged periods of the gamma-ray emission have prompted the suggestion that the source of the energetic protons is acceleration at a coronal mass ej…
Probing Kepler's hottest small planets via homogeneous search and analysis of optical secondary eclipses and phase variations
Scandariato, G.; Pagano, I.; Fossati, L. +5 more
Context. High-precision photometry can lead to the detection of secondary eclipses and phase variations of highly irradiated planets.
Aims: We performed a homogeneous search and analysis of optical occultations and phase variations of the most favorable ultra-short-period (USP) (P < 1 days) sub-Neptunes (Rp < 4 R⊕)…
Open clusters housing classical Cepheids in Gaia DR3
Hao, C. J.; Xu, Y.; Lin, Z. H. +4 more
The latest Gaia Data Release 3 provides an opportunity to expand the census of Galactic open clusters harboring classical Cepheid variables, thereby bolstering the cosmic distance scale. A comprehensive analysis yielded a total of 50 classical Cepheids associated with 45 open clusters, of which 39 open cluster-classical Cepheid pairs are considere…
Pulsating hydrogen-deficient white dwarfs and pre-white dwarfs observed with TESS. III. Asteroseismology of the DBV star GD 358
Kepler, S. O.; Hermes, J. J.; Kawaler, S. D. +14 more
Context. The collection of high-quality photometric data by space telescopes, such as the completed Kepler mission and the ongoing TESS program, is revolutionizing the area of white-dwarf asteroseismology. Among the different kinds of pulsating white dwarfs, there are those that have He-rich atmospheres, and they are called DBVs or V777 Her variab…
The impostor revealed: SN 2016jbu was a terminal explosion
Lyman, J. D.; Fraser, M.; Elias-Rosa, N. +2 more
In this Letter, we present recent observations from the Hubble Space Telescope of the interacting transient SN 2016jbu at +5 yr. We find no evidence for any additional outburst from SN 2016jbu, and the optical source has now faded significantly below the progenitor magnitudes from early 2016. Similar to recent observations of SN 2009ip and SN 2015…
Discovery of eRASSt J192932.9-560346: A bright, two-pole accreting, eclipsing polar
Gromadzki, Mariusz; Buckley, David A. H.; Schwope, Axel +5 more
We report the discovery of a bright (V ~ 15), eclipsing, two-pole accreting magnetic cataclysmic variable (CV), a polar, as counterpart of the SRG/eROSITA and Gaia transients eRASSt J192932.9-560346 and Gaia21bxo. Frequent large-amplitude changes of its brightness at X-ray and optical wavelengths by more than four magnitudes are indicative of a CV…
Variable mass accretion and failed wind explain changing-look phenomena in NGC 1365
Stalin, C. S.; Hryniewicz, K.; Adhikari, T. P. +2 more
Changing-look active galactic nuclei (CLAGNs) show a complex nature in their X-ray spectral shape and line-of-sight column-density variation. The physical mechanisms responsible for these variations are unclear. Here, we study the spectral properties of a CLAGN, NGC 1365 using combined XMM-Newton and NuSTAR observations to understand the CL behavi…
The Close AGN Reference Survey (CARS). Tracing the circumnuclear star formation in the super-Eddington NLS1 Mrk 1044
Jahnke, K.; Gaspari, M.; Combes, F. +11 more
Context. The host galaxy conditions for rapid supermassive black hole growth are poorly understood. Narrow-line Seyfert 1 (NLS1) galaxies often exhibit high accretion rates and are hypothesized to be prototypes of active galactic nuclei (AGN) at an early stage of their evolution.
Aims: We present adaptive optics (AO) assisted VLT MUSE NFM obs…
SN 1987A: Tracing the flux decline and spectral evolution through a comparison of SRG/eROSITA and XMM-Newton observations
Haberl, F.; Freyberg, M. J.; Maggi, P. +3 more
Context. SN 1987A is the supernova closest to us observed in the past four centuries. It provides the unique opportunity of witnessing the birth and evolution of a supernova remnant. Monitoring the source in X-rays provides insights into the physics of the shock, the X-ray emitting plasma, and the interaction of the shock with the structures in th…
Constraining the overcontact phase in massive binary evolution. II. Period stability of known O+O overcontact systems
Mahy, Laurent; Abdul-Masih, Michael; Marchant, Pablo +2 more
Context. Given that mergers are often invoked to explain many exotic phenomena in massive star evolution, understanding the evolutionary phase directly preceding a merger, the overcontact phase, is of crucial importance. Despite this, large uncertainties exist in our understanding of the evolution of massive overcontact binaries.
Aims: We aim…