Search Publications
Brightest cluster galaxies in the extended GMRT radio halo cluster sample. Radio properties and cluster dynamics
Kale, R.; Giacintucci, S.; Venturi, T. +4 more
Aims: First-ranked galaxies in clusters, usually referred to as brightest cluster galaxies (BCGs), show exceptional properties over the whole electromagnetic spectrum. They are the most massive elliptical galaxies and show the highest probability to be radio loud. Moreover, their special location at the centres of galaxy clusters raises the q…
Short-period X-ray oscillations in super-soft novae and persistent super-soft sources
Ness, J. -U.; Henze, M.; Wilms, J. +10 more
Context. Transient short-period (<100 s) oscillations have been found in the X-ray light curves of three novae during their super-soft source (SSS) phase and in one persistent SSS.
Aims: We pursue an observational approach to determine possible driving mechanisms and relations to fundamental system parameters such as the white dwarf mass. …
Insights into gas heating and cooling in the disc of NGC 891 from Herschel far-infrared spectroscopy⋆⋆⋆
Fritz, J.; Cooray, A.; Lebouteiller, V. +15 more
We present Herschel PACS and SPIRE spectroscopy of the most important far-infrared cooling lines in the nearby, edge-on spiral galaxy, NGC 891: [Cii] 158 µm, [Nii] 122, 205 µm, [Oi] 63, 145 µm, and [Oiii] 88 µm. We find that the photoelectric heating efficiency of the gas, traced via the ([Cii]+[Oi]63)/FTIR ratio…
An automated classification approach to ranking photospheric proxies of magnetic energy build-up
McAteer, R. T. J.; Al-Ghraibah, A.; Boucheron, L. E.
Aims: We study the photospheric magnetic field of ~2000 active regions over solar cycle 23 to search for parameters that may be indicative of energy build-up and its subsequent release as a solar flare in the corona.
Methods: We extract three sets of parameters: (1) snapshots in space and time: total flux, magnetic gradients, and neutral…
The evolution of the emission measure distribution in the core of an active region
Del Zanna, Giulio; Tripathi, Durgesh; Mason, Helen +2 more
We study the spatial distribution and evolution of the slope of the emission measure (EM) between 1 MK and 3 MK in the core of the active region (AR) NOAA 11193, first when it appeared near the central meridian and then again when it reappeared after a solar rotation. We use observations recorded by the Extreme-ultraviolet Imaging Spectrometer (EI…
Spatially resolved physical conditions of molecular gas and potential star formation tracers in M 83, revealed by the Herschel SPIRE FTS
Bournaud, F.; Lebouteiller, V.; Madden, S. C. +19 more
We investigate the physical properties of the molecular and ionized gas, and their relationship to the star formation and dust properties in M 83, based on submillimeter imaging spectroscopy from within the central 3.5' (~4 kpc in diameter) around the starburst nucleus. The observations use the Fourier Transform Spectrometer (FTS) of the Spectral …
Depletion of chlorine into HCl ice in a protostellar core. The CHESS spectral survey of OMC-2 FIR 4
Ceccarelli, C.; Dominik, C.; Lis, D. C. +9 more
Context. The freezeout of gas-phase species onto cold dust grains can drastically alter the chemistry and the heating-cooling balance of protostellar material. In contrast to well-known species such as carbon monoxide (CO), the freezeout of various carriers of elements with abundances <10-5 has not yet been well studied.
Aims: O…
Rotating dust particles in the coma of comet 67P/Churyumov-Gerasimenko
Jorda, L.; Lamy, P. L.; Bertaux, J. -L. +43 more
Context. During September and October 2014, the OSIRIS cameras onboard the ESA Rosetta mission detected millions of single particles. Many of these dust particlesappear as long tracks (due to both the dust proper motion and the spacecraft motion during the exposure time) with a clear brightness periodicity.
Aims: We interpret the observed per…
Estimate of the erosion rate from H2O mass-loss measurements from SWAN/SOHO in previous perihelions of comet 67P/Churyumov-Gerasimenko and connection with observed rotation rate variations
Bertaux, Jean-Loup
Context. The SWAN Lyman α photometer onboard SOHO monitored the hydrogen cloud around comet 67P/Churyumov-Gerasimenko (67P) postperihelion at the three last perihelions in 1996, 2002, and 2009.
Aims: Combining the SWAN results with some new Rosetta data allows estimating the erosion rate of the comet, quantified by the thickness of a layer th…
Eta Carinae's 2014.6 spectroscopic event: Clues to the long-term recovery from its Great Eruption
Weis, K.; Davidson, K.; Humphreys, R. M. +9 more
Aims: Every 5.5 years, η Car's light curve and spectrum change remarkably across all observed wavelength bands. These so-called spectroscopic events are most likely caused by the close approach of a companion. We compare the recent spectroscopic event in mid-2014 to the events in 2003 and 2009 and investigate long-term trends.
Methods: E…