Search Publications
The Effect of Hot Coronal Electrons on Extreme-Ultraviolet Spectral Lines of He II Emitted by Solar Transition Region Plasmas
Doschek, G. A.; Feldman, U.; Ralchenko, Yu.
The cause of the lower intensities of extreme-ultraviolet (EUV) He II lines emitted by coronal hole (CH) plasmas compared with quiet Sun (QS) plasmas has been the subject of many studies dating back over half a century. In this paper, we study the effect of small amounts of "hot" electrons at coronal temperatures (Te = 1.4 × 106
Anisotropy evolution of magnetic field fluctuation through the bow shock
Glassmeier, K. -H.; Narita, Y.
Measurement of energy distributions in the wave vector domain reveals how anisotropy of turbulent magnetic field fluctuations evolves as the solar wind encounters the terrestrial bow shock and the magnetosphere. While fluctuations in the solar wind, the magnetosheath, and the magnetospheric cusp regions are characterized by the perpendicular wave …
Kinematics of high proper motion stars determined from high resolution spectra in ground-based ultraviolet
Klochkova, V. G.; Tavolganskaya, N. S.
Radial velocities for 15 stars with high proper motions were measured as a result of spectral observations, conducted with the NES echelle spectrograph of the 6-m BTA telescope in the wavelength range of 3550–5100 Å with a spectral resolution of R=60000. The standard deviation of the measured velocity does not exceed σ ≤ 0.9 km/s for the stars wit…
The Formation of Spheroids in Early-type Spirals: Clues from Their Globular Clusters
Chandar, Rupali; Goudfrooij, Paul; Puzia, Thomas H. +1 more
We use deep Hubble Space Telescope images taken with the Advanced Camera for Surveys (ACS) in the F475W and F814W filters to investigate the globular cluster (GC) systems in four edge-on Sa spiral galaxies covering a factor of four in luminosity. The specific frequencies of the blue GCs in the galaxies in our sample fall in the range 0.34-0.84, si…
Heliospheric Current Sheet Distortions from Adjacent Outflowing Transients: Multi-spacecraft Observations
Lavraud, B.; Fazakerley, A. N.; Owen, C. J. +2 more
The heliospheric current sheet (HCS) is a permanent solar wind feature, with well predicted Earth passages, but it can be structured and its main orientation can be highly distorted. We report new observations from 2 spacecraft in the solar wind (supported by observations from 3 spacecraft in the nightside magnetosheath), showing an evolution acro…
The red-giant CoRoT target HR 7349
Auvergne, M.; Eggenberger, P.; Baudin, F. +19 more
HR 7349 is a bright [V=5.8] red giant observed by CoRoT in the seismofield of the first long run. The outstanding CoRoT light curve allowed the detection of several solar-like oscillation modes (both radial and non-radial). On top of these seismic constraints, our observational knowledge on HR 7349 benefits as well from a precise parallax and deta…
Subarcsecond radio continuum mapping in and around the spiral galaxy NGC3351 using MERLIN
Terlevich, Roberto; Terlevich, Elena; Richards, Anita M. S. +6 more
We report subarcsecond-scale radio continuum observations of a field of 35 × 22 arcmin2 centred in NGC3351 obtained with the Multi-Element Radio Linked Interferometer Network (MERLIN). We found 23 radio sources in this field, six of which are projected within the D25 isophote of the galaxy and three are located inside the cen…
INTEGRAL and Swift/XRT observations of the source PKS 0208-512
Torres, D. F.; Zhang, S.; Wang, J. -M. +3 more
Aims: The active galaxy PKS 0208-512, detected at lower energies by COMPTEL, has been claimed to be a MeV blazar from EGRET. We report on the most recent INTEGRAL observations of the blazar PKS 0208-512, which are supplemented by Swift ToO observations.
Methods: The high energy X-ray and γ-ray emission of PKS 0208-512 during August-Decem…
Using a new set of space-borne particle monitors to investigate solar-terrestrial relations
Anastasiadis, A.; Daglis, I. A.; Tziotziou, K. +2 more
Context. We investigated the solar origin of Solar Particle Events (SPEs) which occurred during four time periods of the 23rd solar cycle with intense solar activity and were detected by the Standard Radiation Environment Monitor (SREM) onboard the INTEGRAL satellite. SREM is a second generation ESA particle radiation monitor, already flying onboa…
Orbital Solutions and Absolute Elements of the Eclipsing Binary EE Aquarii
Sowell, James R.; Wronka, Marissa Diehl; Gold, Caitlin +1 more
EE Aqr is a 7.9 mag Algol variable with a 12 hr orbital period. The Wilson-Devinney program is used to simultaneously solve 11 previously published light curves together with two existing radial velocity curves. The resulting masses are M 1 = 2.24 ± 0.13 M sun and M 2 = 0.72 ± 0.04 M sun, and the radii a…