Search Publications
A Study of the Long-Term Evolution of Quasi-Periodic Oscillations in the Accretion-Powered X-Ray Pulsar 4U 1626-67
Paul, Biswajit; Kumar, Brijesh; Kaur, Ramanpreet +1 more
We report here a study of the long-term properties of quasiperiodic oscillations (QPOs) in an unusual accreting X-ray pulsar, 4U 1626-67. This is a unique accretion-powered X-ray pulsar in which we have found the QPOs to be present during all sufficiently long X-ray observations with a wide range of X-ray observatories. In the present spin-down er…
Anisotropy Signatures of Solar Energetic Particle Transport in a Closed Interplanetary Magnetic Loop
Sáiz, A.; Ruffolo, D.; Bieber, J. W. +2 more
Recent studies have stressed the importance of solar energetic particle (SEP) transport under disturbed interplanetary conditions, including the case of detection inside a closed interplanetary magnetic loop ejected by a preceding solar event. In this case, particles might be observed to arrive from the far leg of the loop, thus arriving at the de…
A New Twist to an Old Story: HE 0450-2958 and the ULIRG → Optically Bright QSO Transition Hypothesis
Wilner, David J.; Wagg, Jeff; Papadopoulos, Padeli P. +1 more
We report on interferometric imaging of the CO J = 1-0 and J = 3-2 line emission from the controversial QSO/galaxy pair HE 0450-2958. The detected CO J = 1-0 line emission is found associated with the disturbed companion galaxy, not the luminous QSO, and implies Mgal(H2) ~ (1-2) × 1010 M⊙, which is gtrsi…
Suzaku Observation of the RCW86 Northeastern Shell
Yamaguchi, Hiroya; Koyama, Katsuji; Nakajima, Hiroshi +4 more
This paper reports on Suzaku results concerning the northeast shell of RCW86. With both spatial and spectral analyses, we separated the X-rays into three distinct components: low (kTe ∼ 0.3keV) and high (kTe ∼ 1.8keV) temperature plasmas and a non-thermal component, and discovered that their spatial distributions are differen…
Causal relationships between eruptive prominences and coronal mass ejections
Filippov, B.; Koutchmy, S.
A close association between eruptive prominences and CMEs, both slow and fast CMEs, was reported in many studies. Sometimes it was possible to follow the material motion starting from the prominence (filament) activation to the CME in the high corona. Remnants of the prominence were found in the bright core of the CME. However, detailed comparison…
High resolution radio study of the pulsar wind nebula within the supernova remnant G0.9+0.1
Decourchelle, A.; Giacani, E.; Dubner, G.
Aims: We have conducted a study in radio wavelengths and in X-rays of the pulsar wind nebula (PWN) in the supernova remnant (SNR) G0.9+0.1 with the goal of investigating in detail its morphology and to accurately determine its characteristic parameters.
Methods: To carry out this research we have observed the PWN at λ3.6 and 6 cm using the Aus…
High resolution spectroscopy of the inner ring of SN 1987A
Sollerman, J.; Lundqvist, P.; Spyromilio, J. +8 more
We discuss high resolution VLT/UVES observations (FWHM ~ 6 km s-1) from October 2002 (day ~5700 past explosion) of the shock interaction of SN 1987A and its circumstellar ring. A large number of narrow emission lines from the unshocked ring, with ion stages from neutral up to Ne V and Fe VII, have been identified. A nebular analysis of …
Modulated reconnection rate and energy conversion at the magnetopause under steady IMF conditions
Dandouras, I.; Buchert, S.; Vaivads, A. +4 more
We use the multi-spacecraft mission Cluster to make observational estimates of the local energy conversion across the dayside high-latitude magnetopause. The energy conversion is estimated during eleven complete magnetopause crossings under steady south-dawnward interplanetary magnetic field (IMF). We describe a new method to determine the reconne…
Near-infra-red spectroscopic ages of massive star clusters in M 82
Smith, L. J.; Gallagher, J. S., III; Mouhcine, M. +3 more
Context: Like other starburst galaxies, M 82 hosts compact, massive (>5 × 105 M⊙) young star clusters that are interesting both in their own right and as benchmarks for population synthesis models.
Aims: In addition to assessing or reassessing the properties of some of the brightest near-IR sources in M 82, this paper …
Evidence That Solar Flares Drive Global Oscillations in the Sun
Kjeldsen, H.; Karoff, C.
Solar flares are large explosions on the Sun's surface caused by a sudden release of magnetic energy. They are known to cause local short-lived oscillations traveling away from the explosion like water rings. Here we show that the energy in the solar acoustic spectrum is correlated with flares. This means that the flares drive global oscillations …