Search Publications
Statistical study of coronal mass ejection source locations: 2. Role of active regions in CME production
Wang, Yuming; Shen, Chenglong; Wang, S. +3 more
This is the second paper of the statistical study of coronal mass ejection (CME) source locations, in which the relationship between CMEs and active regions (ARs) is statistically studied on the basis of the information of CME source locations and the ARs automatically extracted from magnetic synoptic charts of Michelson Doppler Imager (MDI) durin…
Gas temperature profiles in galaxy clusters with Swift XRT: observations and capabilities to map near R200
Moretti, A.; Molendi, S.; Gastaldello, F. +1 more
Aims: We investigate the possibility of using the X-ray telescope (XRT) on board the Swift satellite to improve the current accuracy of the intra-cluster medium (ICM) temperature measurements in the region close to the virial radius of nearby clusters.
Methods: We present the spectral analysis of the Swift XRT observations of 6 galaxy cl…
On the Spin-down and Magnetic Field of the X-ray Pulsar 1E 1207.4-5209
Gotthelf, E. V.; Halpern, J. P.
We analyze all of the archival X-ray timing data from the years 2000-2008 on the weakly magnetized central compact object (CCO) pulsar 1E 1207.4-5209 in an attempt to measure its dipole magnetic field strength via spin-down. because most of these observations were not planned for the purpose of phase-coherent timing, the resulting ephemeris is not…
Hot electrons as tracers of large-scale structure of magnetotail current sheets
Petrukovich, A. A.; Zelenyi, L. M.; Nakamura, R. +1 more
This paper is devoted to the investigation of the vertical electron temperature distribution in thin currents sheets of the Earth magnetotail. The dependence of electron temperature on magnetic field Te(Bx) is examined for 62 thin currents sheet crossings by the Cluster spacecraft. The profiles Te(Bx) ar…
Nonlinear Force-Free Reconstruction of the Global Solar Magnetic Field: Methodology
Contopoulos, I.; Kalapotharakos, C.; Georgoulis, M. K.
We present a novel numerical method that allows the calculation of nonlinear force-free magnetostatic solutions above a boundary surface on which only the distribution of the normal magnetic field component is given. The method relies on the theory of force-free electrodynamics and applies directly to the reconstruction of the solar coronal magnet…
Discovery of the correspondence between intra-cluster radio emission and a high pressure region detected through the Sunyaev-Zel'dovich effect
Croston, J. H.; Bourdin, H.; Mazzotta, P. +9 more
We analyzed new 237 MHz and 614 MHz GMRT data of the most X-ray luminous galaxy cluster, RX J1347-1145. Our radio results are compared with the MUSTANG 90 GHz Sunyaev-Zel'dovich effect map and with re-processed Chandra and XMM-Newton archival data of this cluster. We point out for the first time in an unambiguous way the correspondence between a r…
Rotational modeling of Hyperion
Thomas, Peter C.; Harbison, Rebecca A.; Nicholson, Philip C.
Saturn's moon, Hyperion, is subject to strongly-varying solid body torques from its primary and lacks a stable spin state resonant with its orbital frequency. In fact, its rotation is chaotic, with a Lyapunov timescale on the order of 100 days. In 2005, Cassini made three close passes of Hyperion at intervals of 40 and 67 days, when the moon was i…
An optical/NIR survey of globular clusters in early-type galaxies. I. Introduction and data reduction procedures
Larsen, S. S.; Kuntschner, H.; Chies-Santos, A. L. +3 more
Context. The combination of optical and near-infrared (NIR) colours has the potential to break the age/metallicity degeneracy and offers a better metallicity sensitivity than optical colours alone. Previous tudies of extragalactic globular clusters (GCs) with this colour combination, however, have suffered from small samples or have been restricte…
Thermal properties of the asteroid (2867) Steins as observed by VIRTIS/Rosetta
Erard, S.; Drossart, P.; Capaccioni, F. +6 more
Context. To investigate thermal properties of the small asteroid (2867) Steins, we analyzed its surface thermal emission measured by the VIRTIS instrument during the Rosetta spacecraft (ESA) flyby that occurred in September 2008. VIRTIS performed the first thermal mapping of an asteroid surface.
Aims: We determine the thermal properties of di…
Fokker-Planck Models for M15 Without a Central Black Hole: The Role of the Mass Function
Cohn, Haldan N.; Lugger, Phyllis M.; Murphy, Brian W.
We have developed a set of dynamically evolving Fokker-Planck models for the collapsed-core globular star cluster M15, which directly address the issue of whether a central black hole is required to fit Hubble Space Telescope (HST) observations of the stellar spatial distribution and kinematics. As in our previous work reported by Dull et al., we …