Search Publications
Absence of the strahl during times of slow wind
Goldstein, Melvyn L.; Gurgiolo, Chris
It is not uncommon during periods when the solar wind speed is less than 425 km s-1 to observe near 1 AU no evidence of a strahl population in either the electron solar wind or within the foreshock. Estimating the fluid flow within each energy step returned from the Plasma Electron And Current Experiment (PEACE) on board Cluster-2 often…
The vertical transport of methane from different potential emission types on Mars
Patel, M. R.; Lewis, S. R.; Holmes, J. A.
The contrasting evolutionary behavior of the vertical profile of methane from three potential release scenarios is analyzed using a global circulation model with assimilated temperature profiles. Understanding the evolving methane distribution is essential for interpretation of future retrievals of the methane vertical profile taken by instruments…
Derivation of sideband gain ratio for Herschel/HIFI
Kester, Do; Higgins, Ronan; Teyssier, David
Context. Heterodyne mixers are commonly used for high-resolution spectroscopy at radio telescopes. When used as a double sideband system, the accurate flux calibration of spectral lines acquired by those detectors is highly dependent on the system gains in the respective mixer sidebands via the so-called sideband gain ratio (SBR). As such, the SBR…
Spatially radiative properties of 3C 58 and G21.5-0.9
Zhang, Li; Lu, Fang-Wu; Gao, Quan-Gui +1 more
Observations of two pulsar wind nebulae (PWNe) 3C 58 and G21.5-0.9 indicate that they have mostly symmetric spherical morphologies, emit photons from radio to γ-rays and have the radial variations of the photon indices in X-ray band. The spatially radiative properties of 3C 58 and G21.5-0.9 are modelled in the frame of a spatially dependent model.…
A method to predict magnetopause expansion in radial IMF events by MHD simulations
Å afránková, J.; Němeček, Z.; Sibeck, D. G. +2 more
This paper presents a method for taking into account changes of solar wind parameters in the foreshock using global MHD simulations. We simulate four events with very distant subsolar magnetopause crossings that occurred during quasi-radial interplanetary magnetic field (IMF) intervals lasting from one to several hours. Using previous statistical …
Precise CCD positions of Himalia using Gaia DR1 in 2015-2016
Wang, N.; Peng, Q. Y.; Peng, H. W.
In order to obtain high-precision CCD positions of Himalia, the sixth Jovian satellite, a total of 598 CCD observations have been obtained during the years 2015-2016. The observations were made by using the 2.4 and 1 m telescopes administered by Yunnan Observatories over 27 nights. Several factors that would influence the positional precision of H…
Structure and Dynamics of Cool Flare Loops Observed by the Interface Region Imaging Spectrograph
Heinzel, P.; Berlicki, A.; Liu, W. +1 more
Flare loops were well observed with the Interface Region Imaging Spectrograph (IRIS) during the gradual phase of two solar flares on 2014 March 29 and 2015 June 22. Cool flare loops are visible in various spectral lines formed at chromospheric and transition-region temperatures and exhibit large downflows which correspond to the standard scenario.…
Detection of Coronal Mass Ejections Using Multiple Features and Space-Time Continuity
Zhang, Ling; Yin, Jian-qin; Lin, Jia-ben +2 more
Coronal Mass Ejections (CMEs) release tremendous amounts of energy in the solar system, which has an impact on satellites, power facilities and wireless transmission. To effectively detect a CME in Large Angle Spectrometric Coronagraph (LASCO) C2 images, we propose a novel algorithm to locate the suspected CME regions, using the Extreme Learning M…
Radiative energy balance of Venus: An approach to parameterize thermal cooling and solar heating rates
Kappel, D.; Arnold, G.; Haus, R.
Thermal cooling rates QC and solar heating rates QH in the atmosphere of Venus at altitudes between 0 and 100 km are investigated using the radiative transfer and radiative balance simulation techniques described by Haus et al. (2015b, 2016). QC strongly responds to temperature profile and cloud parameter changes, …
The Stochastic X-Ray Variability of the Accreting Millisecond Pulsar MAXI J0911-655
Bult, Peter
In this work, I report on the stochastic X-ray variability of the 340 Hz accreting millisecond pulsar MAXI J0911-655. Analyzing pointed observations of the XMM-Newton and NuSTAR observatories, I find that the source shows broad band-limited stochastic variability in the 0.01{--}10 {Hz} range with a total fractional variability of ∼ 24 % rms in the…