Search Publications
Radio observations of the region around the pulsar wind nebula HESS J1303-631 with ATCA
Johnston, Simon; Sushch, Iurii; Oya, Igor +2 more
Radio observations of the region surrounding PSR J1301-6305 at 5.5 GHz and 7.5 GHz were conducted with ATCA on September 5, 2013. The observations were dedicated to the search of the radio counterpart of the evolved pulsar wind nebula (PWN) HESS J1303-631, which has been detected in X-rays and GeV-TeV γ-rays. The collected data do not reveal any s…
ALMA Compact Array observations of the Fried Egg nebula. Evidence for large-scale asymmetric mass-loss from the yellow hypergiant IRAS 17163-3907
Galván-Madrid, R.; Olofsson, H.; Justtanont, K. +12 more
Yellow hypergiants are rare and represent a fast evolutionary stage of massive evolved stars. That evolutionary phase is characterised by a very intense mass loss, the understanding of which is still very limited. Here we report ALMA Compact Array observations of a 50''-mosaic toward the Fried Egg nebula, around one of the few Galactic yellow hype…
The cosmological analysis of X-ray cluster surveys. III. 4D X-ray observable diagrams
Pierre, M.; Faccioli, L.; Clerc, N. +4 more
Context. Despite compelling theoretical arguments, the use of clusters as cosmological probes is, in practice, frequently questioned because of the many uncertainties surrounding cluster-mass estimates.
Aims: Our aim is to develop a fully self-consistent cosmological approach of X-ray cluster surveys, exclusively based on observable quantitie…
Spectroscopic confirmation of the low-latitude object FSR 1716 as an old globular cluster
Kunder, Andrea; Wojno, Jennifer; Koch, Andreas
Star clusters are invaluable tracers of the Galactic components and the discovery and characterization of low-mass stellar systems can be used to appraise their prevailing disruption mechanisms and time scales. However, owing to significant foreground contamination, high extinction, and still uncharted interfaces of the underlying Milky Way compon…
Radio and X-ray properties of the source G29.37+0.1 linked to HESS J1844-030
Giacani, E.; Castelletti, G.; Petriella, A. +2 more
Aims: We report on the first detailed multiwavelength study of the radio source G29.37+0.1, which is an as-yet-unclassified object linked to the very-high-energy γ-emitting source HESS J1844-030. The origin of the multiwavelength emission toward G29.37+0.1 has not been clarified so far, leaving open the question about the physical relationshi…
Dusty globules in the Crab Nebula
Gahm, G. F.; Grenman, T.; Elfgren, E.
Context. Dust grains are widespread in the Crab Nebula. A number of small, dusty globules, are visible as dark spots against the background of continuous synchrotron emission in optical images.
Aims: Our aim is to catalogue such dusty globules and investigate their properties.
Methods: From existing broad-band images obtained with the Hu…
Evidence for two-loop interaction from IRIS and SDO observations of penumbral brightenings
Patsourakos, S.; Nindos, A.; Alissandrakis, C. E. +1 more
Aims: We investigate small scale energy release events which can provide clues on the heating mechanism of the solar corona.
Methods: We analyzed spectral and imaging data from the Interface Region Imaging Spectrograph (IRIS), images from the Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatoty (SDO), and magnetograms…
An X-ray view of HD 166734, a massive supergiant system
Nazé, Yaël; Mahy, Laurent; Gosset, Eric +1 more
The X-ray emission of the O+O binary HD 166734 was monitored using Swift and XMM-Newton observatories, leading to the discovery of phase-locked variations. The presence of an f line in the He-like triplets further supports a wind-wind collision as the main source of the X-rays in HD 166734. While temperature and absorption do not vary significantl…
Coronal X-ray emission and planetary irradiation in HD 209458
Schmitt, J. H. M. M.; Czesla, S.; Salz, M. +2 more
HD 209458 is one of the benchmark objects in the study of hot Jupiter atmospheres and their evaporation through planetary winds. The expansion of the planetary atmosphere is thought to be driven by high-energy extreme ultraviolet (EUV) and X-ray irradiation. We obtained new Chandra High Resolution Camera (HRC-I) data, which unequivocally show that…
The XMM deep survey in the CDF-S. X. X-ray variability of bright sources
Vignali, C.; Gilli, R.; Ranalli, P. +6 more
Aims: We aim to study the variability properties of bright hard X-ray selected active galactic nuclei (AGN) in the redshift range between 0.3 and 1.6 detected in the Chandra Deep Field South (XMM-CDFS) by a long ( 3 Ms) XMM observation.
Methods: Taking advantage of the good count statistics in the XMM CDFS, we search for flux and spectra…