Search Publications
Albatross: a scalable simulation-based inference pipeline for analysing stellar streams in the Milky Way
Weniger, Christoph; Alvey, James; Gerdes, Mathis
Stellar streams are potentially a very sensitive observational probe of galactic astrophysics, as well as the dark matter population in the Milky Way. On the other hand, performing a detailed, high-fidelity statistical analysis of these objects is challenging for a number of key reasons. First, the modelling of streams across their (potentially bi…
eRASSt J074426.3 + 291606: prompt accretion disc formation in a 'faint and slow' tidal disruption event
Salvato, M.; Liu, Z.; Buchner, J. +10 more
We report on multiwavelength observations of the tidal disruption event (TDE) candidate eRASSt J074426.3 + 291606 (J0744), located in the nucleus of a previously quiescent galaxy at z = 0.0396. J0744 was first detected as a new, ultra-soft X-ray source (photon index ~4) during the second SRG/eROSITA All-Sky Survey (eRASS2), where it had brightened…
Hidden Cooling Flows in clusters of Galaxies II: a wider sample
Fabian, A. C.; Pinto, C.; Ferland, G. J. +3 more
We have recently uncovered Hidden Cooling Flows (HCFs) in the XMM Reflection Grating Spectrometer spectra of three clusters of galaxies; Centaurus, Perseus, and A1835. Here, we search for them in a wider sample of objects: the X-ray brightest group NGC 5044; four moderate X-ray luminosity clusters Sersic 159, A262, A2052, and RX J0821; and three h…
The ultraviolet habitable zone of exoplanets
Ghirlanda, G.; Ghisellini, G.; Borsa, F. +2 more
The dozens of rocky exoplanets discovered in the circumstellar habitable zone (CHZ) currently represent the most suitable places to host life as we know it outside the Solar system. However, the presumed presence of liquid water on the CHZ planets does not guarantee suitable environments for the emergence of life. According to experimental studies…
The multiwavelength view of shocks in the fastest nova V1674 Her
Mukai, K.; Sokoloski, J. L.; Buson, S. +41 more
Classical novae are shock-powered multiwavelength transients triggered by a thermonuclear runaway on an accreting white dwarf. V1674 Her is the fastest nova ever recorded (time to declined by two magnitudes is t2 = 1.1 d) that challenges our understanding of shock formation in novae. We investigate the physical mechanisms behind nova em…
A Bayesian approach for torque modelling of BeXRB pulsars with application to super-Eddington accretors
Vasilopoulos, G.; Wilson-Hodge, C. A.; Malacaria, C. +3 more
In this study, we present a method to estimate posterior distributions for standard accretion torque model parameters and binary orbital parameters for X-ray binaries using a nested sampling algorithm for Bayesian parameter estimation. We study the spin evolution of two Be X-ray binary systems in the Magellanic Clouds, RX J0520.5-6932 and RX J0209…
ALMACAL VIII: a pilot survey for untargeted extragalactic CO emission lines in deep ALMA calibration data
Hamanowicz, Aleksandra; Lagos, Claudia del P.; Ivison, Rob J. +6 more
We present a pilot, untargeted extragalactic carbon monoxide (CO) emission-line survey using ALMACAL, a project utilizing ALMA calibration data for scientific purposes. In 33 deep (Texp > 40 min) ALMACAL fields, we report six CO emission-line detections above S/N > 4, one-third confirmed by MUSE observations. With this pilot surve…
Abundances of CNO elements in z 0.3-0.4 Lyman continuum leaking galaxies
Chisholm, J.; Schaerer, D.; Ravindranath, S. +4 more
We present observations with the Space Telescope Imaging Spectrograph onboard the Hubble Space Telescope (HST) of 11 Lyman continuum (LyC) leaking galaxies at redshifts, z, in the range 0.29-0.43, with oxygen abundances 12+log(O/H) = 7.64-8.16, stellar masses M⋆ ~ 107.8-109.8 M⊙, and O32 = [O …
SRG/eROSITA discovery of a radio-faint X-ray candidate supernova remnant SRGe J003602.3+605421 = G121.1-1.9
Sunyaev, R. A.; Churazov, E. M.; Khabibullin, I. I. +2 more
We report the discovery of a candidate X-ray supernova remnant SRGe J003602.3+605421 = G121.1-1.9 in the course of the SRG/eROSITA all-sky survey. The object is located at (l, b) = (121.1°, -1.9°), is ≈36 arcmin in angular size, and has a nearly circular shape. Clear variations in the spectral shape of the X-ray emission across the object are dete…
TESS and CHEOPS discover two warm sub-Neptunes transiting the bright K-dwarf HD 15906
Alonso, R.; Deleuil, M.; Erikson, A. +119 more
We report the discovery of two warm sub-Neptunes transiting the bright (G = 9.5 mag) K-dwarf HD 15906 (TOI 461, TIC 4646810). This star was observed by the Transiting Exoplanet Survey Satellite (TESS) in sectors 4 and 31, revealing two small transiting planets. The inner planet, HD 15906 b, was detected with an unambiguous period but the outer pla…