Search Publications
Stereoscopic Polar Plume Reconstructions from STEREO/SECCHI Images
Solanki, S. K.; Plunkett, S. P.; Feng, L. +7 more
We present stereoscopic reconstructions of the location and inclination of polar plumes of two data sets based on the two simultaneously recorded images taken by the EUVI telescopes in the SECCHI instrument package onboard the Solar TErrestrial RElations Observatory spacecraft. The 10 plumes investigated show a superradial expansion in the coronal…
The stellar population content of the thick disc and halo of the Milky Way analogue NGC 891
Rejkuba, M.; Mouhcine, M.; Ibata, R.
We present deep VI images obtained with the Advanced Camera for Surveys on board the Hubble Space Telescope, covering three fields in the north-east side of the edge-on disc galaxy NGC 891. The observed fields span a wide range of galactocentric distances along the eastern minor axis, extending from the plane of the disc to 12 kpc, and out to ∼25 …
The jovian anticyclone BA. III. Aerosol properties and color change
Hueso, R.; Sánchez-Lavega, A.; García-Melendo, E. +2 more
A study of the vertical cloud structure of oval BA and its red color change is presented in this third part of our complete analysis. A large interest in Jupiter's anticyclone BA was created by its reddening that occurred between 2005 and 2006. In this work we quantify the color change in oval BA by using images taken with the Advanced Camera for …
Oxygen ion escape from Venus in a global hybrid simulation: role of the ionospheric O+ ions
Kallio, E.; Janhunen, P.; Barabash, S. +4 more
We study the solar wind induced oxygen ion escape from Venus' upper atmosphere and the Venus Express observations of the Venus-solar wind interaction by the HYB-Venus hybrid simulation code. We compare the simulation to the magnetic field and ion observations during an orbit of nominal upstream conditions. Further, we study the response of the ind…
Is There a Dark Matter Signal in the Galactic Positron Annihilation Radiation?
Rothschild, R. E.; Higdon, J. C.; Lingenfelter, R. E.
Assuming Galactic positrons do not go far before annihilating, a difference between the observed 511 keV annihilation flux distribution and that of positron production, expected from β+ decay in Galactic iron nucleosynthesis, was evoked as evidence of a new source and signal of dark matter. We show, however, that the dark matter sources…
Testing magnetically confined wind shock models for β Cephei using XMM-Newton and Chandra phase-resolved X-ray observations
Sanz-Forcada, J.; Neiner, C.; Favata, F. +2 more
Aims: We have performed a set of high- and low-spectral resolution phase-resolved X-ray observations of the magnetic B star β Cep, for which theoretical models predict the presence of a confined wind emitting X-rays from stationary shocks. Given the peculiar geometry of β Cep, some of the models predict strong rotational modulation of the X-ray em…
The nature of late-type spiral galaxies: structural parameters, optical and near-infrared colour profiles and dust extinction
Balcells, Marc; Peletier, Reynier F.; Falcón-Barroso, Jesús +1 more
We analyse V- and H-band surface photometry of a sample of 18 Sb-Sd galaxies. Combining high-resolution Hubble Space Telescope (HST) images with ground-based near-infrared observations, we extract photometric profiles, which cover the whole disc and provide the highest possible resolution. This is the first photometric study of late-type spirals f…
Texes Observations of M Supergiants: Dynamics and Thermodynamics of Wind Acceleration
Harper, Graham M.; Brown, Alexander; Ryde, Nils +4 more
We have detected [Fe II] 17.94 µm and 24.52 µm emission from a sample of M supergiants (µ Cep, α Sco, α Ori, CE Tau, AD Per, and α Her) using the Texas Echelon Cross Echelle Spectrograph on NASA's Infrared Telescope Facility. These low opacity emission lines are resolved at R sime 50, 000 and provide new diagnostics of the dynami…
X-ray spectral identification of three candidate quiescent low-mass X-ray binaries in the globular cluster NGC 6304
Pavlov, George G.; Guillot, Sebastien; Zavlin, Vyacheslav E. +3 more
We report the search for low-mass X-ray binaries in quiescence (qLMXBs) in the globular cluster NGC 6304 using XMM-Newton observations. We present the spectral analysis leading to the identification of three candidate qLMXBs within the field of this globular cluster (GC), each consistent with the X-ray spectral properties of previously identified …
Endpoint Brightenings in Erupting Filaments
Wang, Y. -M.; Kliem, B.; Muglach, K.
Two well known phenomena associated with erupting filaments are the transient coronal holes that form on each side of the filament channel and the bright post-event arcade with its expanding double row of footpoints. Here we focus on a frequently overlooked signature of filament eruptions: the spike- or fan-shaped brightenings that appear to mark …