Search Publications
Multi-spacecraft Measurement of Turbulence within a Magnetic Reconnection Jet
Khotyaintsev, Yu. V.; Matthaeus, W. H.; Chapman, S. C. +3 more
The relationship between magnetic reconnection and plasma turbulence is investigated using multipoint in situ measurements from the Cluster spacecraft within a high-speed reconnection jet in the terrestrial magnetotail. We show explicitly that work done by electromagnetic fields on the particles, {\boldsymbol{J}}\cdot {\boldsymbol{E}}, has a non-G…
Star-formation histories of local luminous infrared galaxies
Pérez-González, Pablo G.; Arribas, Santiago; Colina, Luis +7 more
We present analysis of the integrated spectral energy distribution (SED) from the ultraviolet (UV) to the far-infrared and Hα of a sample of 29 local systems and individual galaxies with infrared (IR) luminosities between 1011L⊙ and 1011.8L⊙. We combined new narrow-band Hα + [N ii] and broad-band g, r op…
Hydrogen Ly-α and Ly-β full Sun line profiles observed with SUMER/SOHO (1996-2009)
Vial, J. -C.; Wilhelm, K.; Curdt, W. +2 more
Context. Accurate hydrogen spectra emitted by the entire solar disc in the Ly-α and Ly-βlines are valuable for deriving the distribution and the behaviour of atomic hydrogen in the heliosphere, for understanding the UV emissions of solar type stars better, and finally for estimating the solar energy input that mainly initiates the chemical process…
Interplay between heartbeat oscillations and wind outflow in microquasar IGR J17091-3624
Bianchi, Stefano; Janiuk, Agnieszka; Capitanio, Fiamma +1 more
Aims: During the bright outburst in 2011, the black hole candidate IGR J17091-3624 exhibited strong quasi-periodic flare-like events (on timescales of tens of seconds) in some characteristic states, the so-called heartbeat state. From the theoretical point of view, these oscillations may be modeled by the process of accretion disk instability…
Infrared emission of young HII regions: a Herschel/Hi-GAL study
Smith, M. D.; Testi, L.; Molinari, S. +7 more
Context. Investigating the relationship between radio and infrared emission of Hii regions may help shed light on the nature of the ionizing stars and the formation mechanism of early-type stars in general.
Aims: We have taken advantage of recent unbiased surveys of the Galactic plane such as Herschel/Hi-GAL and VLA/CORNISH to study a bona fi…
Evidence for High-frequency QPOs with a 3:2 Frequency Ratio from a 5000 Solar Mass Black Hole
Cenko, S. Bradley; Zoghbi, Abderahmen; Tombesi, Francesco +3 more
Following the discovery of 3:2 resonance quasi-periodic oscillations (QPOs) in M82X-1, we have constructed power density spectra (PDS) of all 15 (sufficiently long) XMM-Newton observations of the ultraluminous X-ray source NGC 1313 X-1 (LX ≈ 2 × 1040 erg s-1). We detect a strong QPO at a frequency of 0.29 ± 0.01 Hz…
Gale crater and impact processes - Curiosity's first 364 Sols on Mars
Bridges, Nathan T.; Mangold, Nicolas; Wiens, Roger C. +18 more
Impact processes at all scales have been involved in the formation and subsequent evolution of Gale crater. Small impact craters in the vicinity of the Curiosity MSL landing site and rover traverse during the 364 Sols after landing have been studied both from orbit and the surface. Evidence for the effect of impacts on basement outcrops may includ…
Effects of the variability of the nucleus of NGC 1275 on X-ray observations of the surrounding intracluster medium
Fabian, A. C.; Pinto, C.; Russell, H. R. +2 more
The active galaxy NGC 1275 lies at the centre of the Perseus cluster of galaxies, which is the X-ray brightest cluster in the Sky. The nucleus shows large variability over the past few decades. We compile a light curve of its X-ray emission covering about 40 years and show that the bright phase around 1980 explains why the inner X-ray bubbles were…
The morphology of the sub-giant branch and red clump reveal no sign of age spreads in intermediate-age clusters
Bastian, N.; Niederhofer, F.
A recent surprise in stellar cluster research, made possible through the precision of Hubble Space Telescope photometry, was that some intermediate-age (1-2 Gyr) clusters in the Large and Small Magellanic Clouds have main-sequence turn-off (MSTO) widths that are significantly broader than would be expected for a simple stellar population (SSP). On…
First INTEGRAL Observations of V404 Cygni during the 2015 Outburst: Spectral Behavior in the 20-650 keV Energy Range
Ubertini, Pietro; Bazzano, Angela; Jourdain, Elisabeth +3 more
In 2015 June, the source V404 Cygni (= GS2023+38) underwent an extraordinary outburst. We present the results obtained during the first revolution dedicated to this target by the INTEGRAL mission and focus on the spectral behavior in the hard X-ray domain, using both SPI and IBIS instruments. The source exhibits extreme variability and reaches flu…