Search Publications
Secondary-electron radiation accompanying hadronic GeV-TeV gamma-rays from supernova remnants
Wang, Wei; Li, Zhuo; Huang, Yan +1 more
The synchrotron radiation from secondary electrons and positrons (SEPs) generated by hadronic interactions in the shock of supernova remnant (SNR) could be a distinct evidence of cosmic ray (CR) production in SNR shocks. Here, we provide a method where the observed gamma-ray flux from SNRs, created by pion decays, is directly used to derive the SE…
Evolution of MAXI J1631-479 during the January 2019 outburst observed by INTEGRAL/IBIS
Masetti, N.; Charles, P. A.; Bird, A. J. +8 more
We report on a recent bright outburst from the new X-ray binary transient MAXI J1631-479, observed in January 2019. In particular, we present the 30-200 keV analysis of spectral transitions observed with INTEGRAL/IBIS during its Galactic plane monitoring program. In the MAXI and BAT monitoring period, we observed two different spectral transitions…
The Ophiuchus stream progenitor: a new type of globular cluster and its possible Sagittarius connection
Bovy, Jo; Fattahi, Azadeh; Navarro, Julio F. +2 more
The Ophiuchus stream is a short arc-like stellar feature of uncertain origin located ∼5 kpc North of the Galactic centre. New proper motions from the second Gaia data release reconcile the direction of motion of stream members with the stream arc, resolving a puzzling mismatch reported in earlier work. We use N-body simulations to show that the st…
Leveraging HST with MUSE: II. Na-abundance variations in intermediate age star clusters
Martocchia, S.; Salaris, M.; Larsen, S. +13 more
Ancient (>10 Gyr) globular clusters (GCs) show chemical abundance variations in the form of patterns among certain elements, e.g. N correlates with Na and anticorrelates with O. Recently, N abundance spreads have also been observed in massive star clusters that are significantly younger than old GCs, down to an age of ~2 Gyr. However, so far N …
Chandra observations of the planetary nebula IC 4593
Bianchi, L.; Chu, Y. -H.; Guerrero, M. A. +2 more
The Advanced CCD Imaging Spectrometer (ACIS-S) camera on board the Chandra X-ray Observatory has been used to discover a hot bubble in the planetary nebula (PN) IC 4593, the most distant PN detected by Chandra so far. The data are used to study the distribution of the X-ray-emitting gas in IC 4593 and to estimate its physical properties. The hot b…
On the Geometry of the X-ray emission from pulsars a consistent inclination and beaming solution for the Be/X-ray pulsar SXP 1062
Zezas, A.; Coe, M. J.; Roy, A. +4 more
SXP 1062 is a long-period X-ray pulsar (XRP) with a Be optical companion located in the Small Magellanic Cloud. First discovered in 2010 from XMM-Newton data, it has been the target of multiple observational campaigns due to the seeming incongruity between its long spin period and recent birth. In our continuing modelling efforts to determine the …
Infrared colours and spectral energy distributions of hard X-ray selected obscured and Compton-thick active galactic nuclei
Goto, T.; Güver, T.; Kilerci Eser, Ece +2 more
We investigate the infrared colours and spectral energy distributions (SEDs) of 338 X-ray selected active galactic nuclei (AGNs) from the Swift/Burst Alert Telescope (BAT) 105-month survey catalogue, which have been detected using AKARI, in order to find new selection criteria for Compton-thick AGNs. By combining data from the Galaxy Evolution Exp…
Unveiling Vela - variability of interstellar lines in the direction of the Vela supernova remnant - III. Na D and Ca II K
Muneer, S.; Lambert, David L.; Reddy, Arumalla B. S. +4 more
High-resolution optical spectra were obtained in 2017-2019 with The Southern African Large Telescope of 15 stars in the direction of the Vela supernova remnant. Interstellar Ca II H & K and Na I D lines are discussed in this paper. In particular, the line profiles are compared with profiles at a comparable spectral resolution obtained in 1993-…
The detection of solid phosphorus and fluorine in the dust from the coma of comet 67P/Churyumov-Gerasimenko
Cottin, Hervé; Fray, Nicolas; Bardyn, Anaïs +8 more
Here, we report the detection of phosphorus and fluorine in solid particles collected from the inner coma of comet 67P/Churyumov-Gerasimenko measured with the COmetary Secondary Ion Mass Analyser (COSIMA) instrument on-board the Rosetta spacecraft, only a few kilometers away from the comet nucleus. We have detected phosphorus-containing minerals f…
A catalogue of intermediate-duration Type I X-ray bursts observed with the INTEGRAL satellite
Lund, N.; Chenevez, J.; Brandt, S. +1 more
We present a catalogue of long-duration bursts observed with the Joint European X-ray Monitor and IBIS/ISGRI instruments onboard the INTEGRAL satellite. The 14 bursts have e-folding times ranging from 55 s to ≈17 min, and are therefore classified as intermediate-duration bursts, caused by the ignition of an unusually thick helium layer. Though sev…