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Oscillations in the wake of a flare blast wave

Innes, D. E.; Stenborg, G.; Tothova, D.

Context. Oscillations of coronal loops in the Sun have been reported in both imaging and spectral observations at the onset of flares. Images reveal transverse oscillations, whereas spectra detect line-of-sight velocity or Doppler-shift oscillations. The Doppler-shift oscillations are commonly interpreted as longitudinal modes.
Aims: Our aim …

INTEGRAL and Swift observations of IGR J19294+1816 in outburst

Walter, R.; Ferrigno, C.; Bozzo, E. +1 more

Context. IGR J19294+1816 was discovered by INTEGRAL in 2009 during a bright X-ray outburst and was classified as a possible Be X-ray binary or supergiant fast X-ray transient.
Aims: On 2010 October 28, the source displayed a second X-ray outburst and a two months-long monitoring with Swift was carried out to follow the evolution of the source…

Aram Chaos and its constraints on the surface heat flux of Mars

Zegers, Tanja E.; Schumacher, Sandra

The surface heat flux of a planet is an important parameter to characterize its internal activity and to determine its thermal evolution. Here we report on a new method to constrain the surface heat flux of Mars during the Hesperian. For this, we explore the consequences for the martian surface heat flux from a recently presented new hypothesis fo…

Understanding the Dynamics of Magnetic Reconnection Layer

Yamada, Masaaki

We review progress in understanding the dynamics of a typical magnetic reconnection layer by describing the historical development of theory and the recent findings and discoveries in space and laboratory plasmas. The emphasis is on the dynamics of electrons moving with respect to ions in the collision-free neutral sheet. We make a detailed compar…

The Curious Case of the Alpha Persei Corona: A Dwarf in Supergiant's Clothing?

Ayres, Thomas R.

Alpha Persei (HD 20902: F5 Iab) is a luminous, nonvariable supergiant located at the blue edge of the Cepheid instability strip. It is one of the brightest coronal X-ray sources in the young open cluster bearing its name, yet warm supergiants as a class generally avoid conspicuous high-energy activity. The Cosmic Origins Spectrograph on the Hubble…

Unlocking the nature of ultraluminous X-ray sources using their X-ray spectra

Done, C.; Roberts, T. P.; Gladstone, J. C.

We explore the nature of ultraluminous X-ray sources through detailed investigations of their spectral shape using some of the highest quality data available in the XMM-Newton public archives. Phenomenological models allow us to characterise their spectra, while more 'physically-motivated' models enable us to explore the physical processes underly…

Kink-like mode of a double gradient instability in a compressible plasma current sheet

Korovinskiy, D. B.; Semenov, V. S.; Erkaev, N. V. +4 more

A linear MHD instability of the electric current sheet, characterized by a small normal magnetic field component, varying along the sheet, is investigated. The tangential magnetic field component is modeled by a hyperbolic function, describing Harris-like variations of the field across the sheet. For this problem, which is formulated in a 3D domai…

Water ice sublimation-related landforms on Mars

Mangold, N.

Suzaku X-Ray Follow-Up Observation of Weak-Lensing-Detected Halos in the Field around ZwCl 0823.2+0425

Smith, Graham P.; Babul, Arif; Nakazawa, Kazuhiro +6 more

We present the results of a Suzaku X-ray follow-up observation of weak-lensing-detected halos in the field around galaxy cluster ZwCl 0823.2+0425. We clearly detected X-ray emission associated with most of these halos, and determined their detailed physical parameters, such as the X-ray luminosity, temperature, and metal abundance, for the first t…

Period switching in the symbiotic star BX Mon

Formiggini, Liliana; Leibowitz, Elia M.

We report on a detailed analysis of the optical light curve (LC) of the symbiotic system BX Mon, the data of which were gathered from the literature. The LC covers the period from 1889 December to 2009 March, with a gap of no observations between 1940 March and 1972 February. The LC is characterized by strong oscillations of peak-to-peak amplitude…