Search Publications
Herschel-PACS observations of [OI] and H2O in Chamaeleon II
Duchêne, G.; Dent, W. R. F.; Kamp, I. +11 more
Context. Gas plays a major role in the dynamical evolution of protoplanetary discs. Its coupling with the dust is the key to our understanding of planetary formation. Studying the gas content is therefore a crucial step towards understanding protoplanetary discs evolution. Such a study can be made through spectroscopic observations of emission lin…
New view on exoplanet transits. Transit of Venus described using three-dimensional solar atmosphere STAGGER-grid simulations
Tanga, P.; Chiavassa, A.; Asplund, M. +5 more
Context. An important benchmark for current observational techniques and theoretical modeling of exoplanet atmospheres is the transit of Venus (ToV). Stellar activity and, in particular, convection-related surface structures, potentially cause fluctuations that can affect the transit light curves. Surface convection simulations can help interpreti…
Supercriticality of ICME and CIR shocks
Zhou, Xiaoyan; Smith, Edward J.
Interplanetary coronal mass ejection (ICME) and corotating interaction region (CIR) shocks are characterized in terms of supercriticality introduced by Edmiston and Kennel (1984) to classify shocks based on whether dissipation is provided by electron resistivity alone or also requires ion viscosity. The condition for determining supercriticality i…
Characterization of an Acousto-optic tunable filter for development of a near-IR spectrometer for planetary science
Agrawal, Prince; Nandi, A.; Sudhakar, M. +4 more
The development of a spectrometer is being carried out in the Near-Infrared (NIR) wavelength range of 1.0-1.7 µm using an Acousto-Optic Tunable Filter (AOTF). The AOTF is based on Tellurium-di-oxide (TeO2) crystal that acts as a dispersing medium and is driven by an external Radio Frequency (RF) signal. The characterization of AOT…
How do fast impulse CMEs related to powerful flares but unrelated to eruptive filaments appear and move?
Fainshtein, V. G.; Zagainova, Iu. S.
GOES-12/SXI and SDO/AIA data were used to examine the formation and initial stage of movement for several fast pulse 'halo'-type coronal mass ejections (HCMEs) that were related to GOES M and X class flares but unrelated to solar filament eruptions. According to their formation, the HCMEs under study can be subdivided into three groups: (i) Most o…
Experimental test of the ρ(1-α) evolution for rotational discontinuities: cluster magnetopause observations
Marghitu, O.; Klecker, B.; Paschmann, G. +1 more
Rotational discontinuities (RDs) are governed by two relations: the Walén relation predicting that the plasma velocity observed in the deHoffmann-Teller frame equals the local Alfvén velocity and another relation that connects the variation in plasma mass density, ρ, to variations in the pressure anisotropy factor, α, defined as α: ≡(p
Dust Heating By Low-mass Stars in Massive Galaxies at z< 1
Taniguchi, Y.; Kajisawa, M.; Ichikawa, T. +3 more
Using the Hubble Space Telescope/Wide Field Camera 3 imaging data and multi-wavelength photometric catalog, we investigated the dust temperature of passively evolving and star-forming galaxies at 0.2\lt z\lt 1.0 in the CANDELS fields. We estimated the stellar radiation field by low-mass stars from the stellar mass and surface brightness profile of…
Coronae of stars with supersolar elemental abundances
Behar, Ehud; Peretz, Uria; Drake, Stephen A.
Coronal elemental abundances are known to deviate from the photospheric values of their parent star, with the degree of deviation depending on the first ionization potential (FIP). This study focuses on the coronal composition of stars with supersolar photospheric abundances. We present the coronal abundances of six such stars: 11 LMi, ι Hor, HR 7…
Discovery of an optical and X-ray synchrotron jet in NGC 7385
Birkinshaw, M.; Worrall, D. M.; Rawes, J.
We report the discovery of optical and X-ray synchrotron emission from the brighter radio jet in galaxy NGC 7385 using data from HST and Chandra. The jet has a projected length of 5 kpc and a similar morphology to other known optical jets in low-power radio galaxies. We also report a strong jet-cloud interaction which appears to be deflecting the …
The use of the Poynting vector in interpreting ULF waves in magnetospheric waveguides
Wright, A. N.; Elsden, T.
We numerically model ultralow frequency (ULF) waves in the magnetosphere assuming an ideal, low-β, inhomogeneous plasma waveguide. The waveguide is based on the hydromagnetic box model. We develop a novel boundary condition that drives the magnetospheric boundary by pressure perturbations, in order to simulate solar wind dynamic pressure fluctuati…