Search Publications
Particle dynamics in a non-flaring solar active region model
Parnell, C. E.; Neukirch, T.; Threlfall, J. +1 more
Aims: The aim of this work is to investigate and characterise particle behaviour in an (observationally-driven) 3D magnetohydrodynamic (MHD) model of the solar atmosphere above a slowly evolving, non-flaring active region.
Methods: We use a relativistic guiding-centre particle code to investigate the behaviour of selected particle orbits…
On the accretion process in a high-mass star forming region. A multitransitional THz Herschel-HIFI study of ammonia toward G34.26+0.15
Menten, K. M.; Persson, C. M.; Olberg, M. +8 more
Aims: Our aim is to explore the gas dynamics and the accretion process in the early phase of high-mass star formation.
Methods: The inward motion of molecular gas in the massive star forming region G34.26+0.15 is investigated by using high-resolution profiles of seven transitions of ammonia at THz frequencies observed with Herschel-HIFI.…
The 2015 outburst of the accreting millisecond pulsar IGR J17511-3057 as seen by INTEGRAL, Swift, and XMM-Newton
Torres, D. F.; Romano, P.; Ferrigno, C. +5 more
We report on INTEGRAL, Swift, and XMM-Newton observations of IGR J17511-3057 performed during the outburst that occurred between March 23 and April 25, 2015. The source reached a peak flux of 0.7(2) × 10-9 erg cm-2 s-1 and decayed to quiescence in approximately a month. The X-ray spectrum was dominated by a power l…
Planck's Dusty GEMS. II. Extended [CII] emission and absorption in the Garnet at z = 3.4 seen with ALMA
Kneissl, R.; Le Floc'h, E.; Falgarone, E. +9 more
We present spatially resolved ALMA [CII] observations of the bright (flux density S350 = 400 mJy at 350 µm), gravitationally lensed, starburst galaxy PLCK G045.1+61.1 at z = 3.427, the "Garnet". This source is part of our set of "Planck's Dusty GEMS", discovered with the Planck's all-sky survey. Two emission-line clouds with a rel…
X-ray and optical spectroscopy of the massive young open cluster IC 1805
Nazé, Y.; Rauw, G.
Context. Very young open clusters are ideal places to study the X-ray properties of a homogeneous population of early-type stars. In this respect, the IC 1805 open cluster is very interesting as it hosts the O4 If+ star HD 15570 thought to be in an evolutionary stage intermediate between a normal O-star and a Wolf-Rayet star.
Aims:…
Triangulum galaxy viewed by Planck
Chemin, L.; Nucita, A. A.; De Paolis, F. +9 more
We used Planck data to study the M 33 galaxy and find a substantial temperature asymmetry with respect to its minor axis projected onto the sky plane. This temperature asymmetry correlates well with the HI velocity field at 21 cm, at least within a galactocentric distance of 0.5°, and it is found to extend up to about 3° from the galaxy center. We…
Herschel/HIFI observations of the circumstellar ammonia lines in IRC+10216
Menten, K. M.; Olofsson, H.; Marston, A. P. +14 more
Context. A discrepancy exists between the abundance of ammonia (NH3) derived previously for the circumstellar envelope (CSE) of
Aims: To address the discrepancy described above…
IGR J17451-3022: A dipping and eclipsing low mass X-ray binary
Ponti, G.; Romano, P.; Ferrigno, C. +10 more
In this paper we report on the available X-ray data collected by INTEGRAL, Swift, and XMM-Newton during the first outburst of the INTEGRAL transient IGR J17451-3022, discovered in 2014 August. The monitoring observations provided by the JEM-X instruments on board INTEGRAL and the Swift /XRT showed that the event lasted for about 9 months and that …
Investigating the cores of fossil systems with Chandra
Bharadwaj, V.; Sanders, J. S.; Reiprich, T. H. +1 more
Aims: We aim to systematically investigate the cores of a sample of fossil galaxy groups and clusters ("fossil systems"), using Chandra data, to see what hints they can offer about the properties of the intracluster medium in these particular objects.
Methods: We chose a sample of 17 fossil systems from literature with archival Chandra d…
Long-term R and V-band monitoring of some suitable targets for the link between ICRF and the future Gaia celestial reference frame
Souchay, J.; Taris, F.; Andrei, A. +3 more
Context. The Gaia astrometric mission of the European Space Agency was launched on December 2013. It will provide a catalog of 500 000 quasars. Some of these targets will be chosen to build an optical reference system that will be linked to the International Celestial Reference Frame (ICRF). The astrometric coordinates of these sources will have r…