Search Publications
Far Ultraviolet Spectroscopy of Seven Nova-Like Variables
Sion, Edward M.; Ballouz, Ronald-Louis; Mizusawa, Trisha +6 more
We present the results of a multicomponent synthetic spectral analysis of the archival far ultraviolet spectra of several key nova-like variables including members of the SW Sex, RW Tri, UX UMa, and VY Scl subclasses: KR Aur, RW Tri, V825 Her, V795 Her, BP Lyn, V425 Cas, and HL Aqr. Accretion rates as well as the possible flux contribution of the …
Updated phase coherent timing solution of the isolated neutron star RX J0720.4-3125 using recent XMM-Newton and Chandra observations
Haberl, F.; de Vries, C. P.; Vink, J. +4 more
Aims: Since the last phase coherent timing solution of the nearby radio-quiet isolated neutron star RX J0720.4-3125 six new XMM-Newton and three Chandra observations were carried out. The phase coherent timing solutions from previous authors were performed without restricting to a fixed energy band. However, we recently showed that the phase …
Characterization of Transitions in the Solar Wind Parameters
Perri, S.; Balogh, A.
The distinction between fast and slow solar wind streams and the dynamically evolved interaction regions is reflected in the characteristic fluctuations of both the solar wind and the embedded magnetic field. High-resolution magnetic field data from the Ulysses spacecraft have been analyzed. The observations show rapid variations in the magnetic f…
Post-flare evolution of AR 10923 with Hinode/XRT
Parenti, S.; Reale, F.; Reeves, K. K.
Context. Flares are dynamic events which involve rapid changes in coronal magnetic topology end energy release. Even if they may be localized phenomena, the magnetic disturbance at their origin may propagate and be effective in a larger part of the active region.
Aims: We investigate the temporal evolution of a flaring active region with resp…
Observed Core of a Gradual Solar Energetic Particle Event
Thompson, B. J.; Valtonen, E.; Kocharov, L. +2 more
Using space-borne particle and EUV detection and radio spectrograms from both ground-based and space-borne instruments, we study the first phase of the major solar energetic particle (SEP) event associated with the western solar flare and fast and wide coronal mass ejection (CME) on 2000 April 4. The SEP event being observed at the magnetic connec…
Periodic variability in the emission spectrum of T Tauri
Ismailov, N. Z.; Quliev, N. K.; Khalilov, O. V. +1 more
Context. Long timescale periodic variations in T Tauri stars may be related to changes in their protoplanetary disks.
Aims: A lengthy homogeneous series of spectral observations of the CTTS T TauN has been analyzed.
Methods: We search for periodicity in the equivalent widths of the emission lines in the optical and in the UV.
Result…
Suzaku Observation of the Anomalous X-Ray Pulsar 1E 1841-045
Terada, Yukikatsu; Ueno, Masaru; Takahashi, Hiromitsu +7 more
We report on the results of a Suzaku observation of the anomalous X-ray pulsar (AXP) 1E 1841-045 at the center of the supernova remnant Kes 73. We confirmed that the energy-dependent spectral models obtained by previous separate observations were also satisfied over a wide energy range from 0.4 to ∼70 keV, simultaneously. Here, the models below ∼1…
Absolute Radiometric Calibration of the EUNIS-06 170-205 Å Channel and Calibration Update for Coronal Diagnostic Spectrometer/Normal-Incidence Spectrometer
Brosius, Jeffrey W.; Thomas, Roger J.; Davila, Joseph M. +2 more
The Extreme-Ultraviolet Normal-Incidence Spectrograph sounding-rocket payload was flown on 2006 April 12 (EUNIS-06), carrying two independent imaging spectrographs covering wavebands of 300-370 Å in first order and 170-205 Å in second order, respectively. The absolute radiometric response of the EUNIS-06 long-wavelength (LW) channel was directly m…
EUV Spectra of the Full Solar Disk: Analysis and Results of the Cosmic Hot Interstellar Plasma Spectrometer (CHIPS)
Hurwitz, M.; Sirk, M. M.; Marchant, W.
We analyze EUV spectra of the full solar disk from the Cosmic Hot Interstellar Plasma Spectrometer (CHIPS) spanning a period of two years. The observations were obtained via a fortuitous off-axis light path in the 140 - 275 Å passband. The general appearance of the spectra remained relatively stable over the two-year time period, but did show sign…
A joint Chandra and XMM-Newton view of Abell 3158: a massive off-centre cool gas clump as a robust diagnostic of a merger stage
Xu, Haiguang; Zhang, Zhongli; Gu, Liyi +5 more
In previous works, the nearby galaxy cluster Abell 3158 was reported to possess a relatively regular, relaxed morphology in the X-ray band. By analysing the Chandra and XMM-Newton archived data of Abell 3158, we have identified a bow-edge-shaped discontinuity in the X-ray surface brightness distribution about 120h-171 kpc wes…