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The high-energy environment in the super-Earth system CoRoT-7
Schmitt, J. H. M. M.; Czesla, S.; Lalitha, S. +3 more
High-energy irradiation of exoplanets has been identified to be a key influence on the stability of these planets' atmospheres. So far, irradiation-driven mass-loss has been observed only in two Hot Jupiters, and the observational data remain even more sparse in the super-Earth regime. We present an investigation of the high-energy emission in the…
Searching for the orbital period of the ultraluminous X-ray source NGC 1313 X-2
Falomo, R.; Soria, R.; Zampieri, L. +2 more
We analysed the longest phase-connected photometric data set available for NGC 1313 X-2, looking for the ∼6-day modulation reported by Liu et al.. The folded B-band light curve shows a ∼6-day periodicity with a significance slightly larger than 3σ. The low statistical significance of this modulation, along with the lack of detection in the V band,…
X-ray follow-up observations of the two γ-ray pulsars PSR J1459-6053 and PSR J1614-2230
Hill, A. B.; Guillemot, L.; Rea, N. +6 more
Aims: We have observed two newly detected γ-ray pulsars, PSR J1459-6053 and PSR J1614-2230, in the X-ray domain with XMM-Newton to try to enlarge the sample of pulsars for which multi-wavelength data exist. We use these data with the aim of understanding the pulsar emission mechanisms of these pulsars.
Methods: We analysed the X-ray spec…
Re-examining the XMM-Newton spectrum of the black hole candidate XTE J1652-453
Fabian, A. C.; Reis, R. C.; Walton, D. J. +1 more
The XMM-Newton spectrum of the black hole candidate XTE J1652-453 shows a broad and strong Fe Kα emission line, generally believed to originate from reflection of the inner accretion disc. These data have been analysed by Hiemstra et al. using a variety of phenomenological models. We re-examine the spectrum with a self-consistent relativistic refl…
Magnetic Helicity Transported by Flux Emergence and Shuffling Motions in Solar Active Region NOAA 10930
Zhang, Y.; Takizawa, K.; Kitai, R.
We present a new methodology which can determine magnetic helicity transport by the passage of helical magnetic field lines from the sub-photosphere and the shuffling motions of footpoints of preexisting coronal field lines separately. It is well known that only the velocity component, which is perpendicular to the magnetic field (υ B )…
Non-thermal "Burst-on-Tail" of Long-Duration Solar Event on 26 October 2003
Struminsky, A.; Zimovets, I.
Observations of a rare long-duration solar event of GOES class X1.2 from 26 October 2003 are presented. This event showed a pronounced burst of hard X-ray and microwave emission, which was extremely delayed (> 60 min) with respect to the main impulsive phase and did not have any significant response visible in soft X-ray emission. We refer to t…
Extranuclear Hα-emitting complexes in low-z (U)LIRGs: precursors of tidal dwarf galaxies?
Colina, L.; Arribas, S.; Miralles-Caballero, D.
This paper characterizes the physical and kinematic properties of external massive star-forming regions in a sample of (U)LIRGs. We use high angular resolution ACS images from the Hubble Space Telescope (HST) in F435W (~B) and F814W (~I) bands, as well as Hα -line emission maps obtained with integral field spectroscopy. We find 31 external Hα -emi…
The radio spectra of reddened Two Micron All Sky Survey quasi-stellar objects: evidence for young radio jets
Georgakakis, A.; Hopkins, A. M.; Afonso, J. +1 more
Multifrequency radio continuum observations (1.4-22 GHz) of a sample of reddened quasi-stellar objects (QSOs) are presented. We find a high incidence (13/16) of radio spectral properties, such as low-frequency turnovers, high-frequency spectral breaks or steep power-law slopes, similar to those observed in powerful compact steep spectrum (CSS) and…
Correlations Between CME Parameters and Sunspot Activity
Du, Zhanle
Smoothed monthly mean coronal mass ejection (CME) parameters (speed, acceleration, central position angle, angular width, mass, and kinetic energy) for Cycle 23 are cross-analyzed, showing that there is a high correlation between most of them. The CME acceleration (a) is highly correlated with the reciprocal of its mass (M), with a correlation coe…
Magnetic field amplification in electron phase-space holes and related effects
Baumjohann, W.; Treumann, R. A.
Three-dimensional electron phase-space holes are shown to have positive charges on the plasma background, which produce a radial electric field and force the trapped electron component into an azimuthal drift. In this way electron holes generate magnetic fields in the hole. We solve the cylindrical hole model exactly for the hole charge, electric …