Search Publications
Multi-wavelength observations and modelling of a canonical solar flare
Klimchuk, J. A.; Gallagher, P. T.; Milligan, R. O. +1 more
Aims: We investigate the temporal evolution of temperature, emission measure, energy loss, and velocity in a C-class solar flare from both observational and theoretical perspectives.
Methods: The properties of the flare were derived by following the systematic cooling of the plasma through the response functions of a number of instruments - th…
The Three-Dimensional Dynamic Structure of the Inner Orion Nebula
Abel, N. P.; O'Dell, C. R.; Henney, W. J. +2 more
The three-dimensional structure of the brightest part of the Orion Nebula is assessed in the light of published and newly established data. We find that the widely accepted model of a concave blister of ionized material needs to be altered in the southwest direction from the Trapezium, where we find that the Orion-S feature is a separate cloud of …
High-energy characteristics of the schizophrenic pulsar PSR J1846-0258 in Kes 75. Multi-year RXTE and INTEGRAL observations crossing the magnetar-like outburst
Kuiper, L.; Hermsen, W.
Aims: PSR J1846-0258 is a young rotation-powered pulsar with one of the highest surface magnetic field strengths, located in the centre of SN-remnant Kes-75. In June 2006 a magnetar-like outburst took place. Using multi-year RXTE and INTEGRAL observations covering the epoch of the outburst, we aim to study the temporal and spectral characteristics…
The X-ray view of giga-hertz peaked spectrum radio galaxies
Guainazzi, M.; Piconcelli, E.; Grandi, P. +5 more
Context: This paper presents the X-ray properties of a flux- and volume-limited complete sample of 16 giga-hertz peaked spectrum (GPS) galaxies.
Aims: This study addresses three basic questions in our understanding of the nature and evolution of GPS sources: a) What is the physical origin of the X-ray emission in GPS galaxies? b) Which physica…
The NGC 300 Transient: An Alternative Method for Measuring Progenitor Masses
Williams, Benjamin F.; Dolphin, Andrew; Dalcanton, Julianne J. +3 more
We present an alternative technique for measuring the precursor masses of transient events in stars undergoing late stage stellar evolution. We use the well-established techniques of stellar population modeling to age-date the stars surrounding the site of the recent transient event in NGC 300 (NGC 300 OT2008-1). The surrounding stars must share a…
Correlated X-Ray and Very High Energy Emission in the Gamma-Ray Binary LS I +61 303
Maraschi, L.; Covino, S.; Antonelli, L. A. +153 more
The discovery of very high energy (VHE) gamma-ray emitting X-ray binaries has triggered an intense effort to better understand the particle acceleration, absorption, and emission mechanisms in compact binary systems, which provide variable conditions along eccentric orbits. Despite this, the nature of some of these systems, and of the accelerated …
Some Like It Hot: Coronal Heating Observations from Hinode X-ray Telescope and RHESSI
Lin, L.; Golub, L.; Schmelz, J. T. +7 more
We have used Hinode X-Ray Telescope observations and RHESSI upper limits together to characterize the differential emission measure (DEM) from a quiescent active region. We find a relatively smooth DEM curve with the expected active region peak at log T = 6.4. We also find a high-temperature component with significant emission measure at log T gsi…
The velocity field of sunspot penumbrae. I. A global view
Franz, M.; Schlichenmaier, R.
Aims. We investigated the vertical penumbral plasma flow on small spatial scales using data recorded by the spectropolarimeter of the solar optical telescope onboard Hinode.
Methods: We computed maps of apparent Doppler velocities by comparing the spectral positions of the Fe I 630.15 nm & Fe I 630.25 nm lines with the averaged line profil…
New Observation of Failed Filament Eruptions: The Influence of Asymmetric Coronal Background Fields on Solar Eruptions
Liu, Y.; Shibata, K.; Lin, H. +3 more
Failed filament eruptions not associated with a coronal mass ejection (CME) have been observed and reported as evidence for solar coronal field confinement on erupting flux ropes. In those events, each filament eventually returns to its origin on the solar surface. In this Letter, a new observation of two failed filament eruptions is reported whic…
Possible pingo fields in the Utopia basin, Mars: Geological and climatical implications
de Pablo, Miguel Ángel; Komatsu, Goro
The presence of pingos on Mars has been hypothesized since the period of the Viking mission. In fact, a diverse range of pingo-like features has been found at various martian sites including Elysium, Chryse and Utopia Planitiae in the northern lowlands. Due to the morphology and the geological setting, some of those features were interpreted in di…