Search Publications
Quest for the Donor Star in the Magnetic Precataclysmic Variable V1082 Sgr
González, J. F.; Zharikov, S.; Tovmassian, G. +3 more
We obtained high-resolution spectra and multicolor photometry of V1082 Sgr to study the donor star in this 20.8 hr orbital period binary, which is assumed to be a detached system. We measured the rotational velocity (v\sin i=26.5+/- 2.0 km s-1), which, coupled with the constraints on the white dwarf mass from the X-ray spectroscopy, lea…
Photometric and spectral observations of two W UMa stars with periods of one third of a day
Kjurkchieva, D. P.; Marchev, D. V.; Popov, V. A.
Impact of measurement errors on the inferred stellar asteroseismic ages. Statistical models for intermediate age main sequence and red giant branch stars
Valle, G.; Dell'Omodarme, M.; Prada Moroni, P. G. +1 more
Aims: We aim to perform a theoretical investigation on the direct impact of measurement errors in the observational constraints on the recovered age for stars in main sequence (MS) and red giant branch (RGB) phases. We assumed that a mix of classical (effective temperature Teff and metallicity [Fe/H]) and asteroseismic (Δν and ν
Scale heights and detached haze layers in the mesosphere of Venus from SPICAV IR data
Montmessin, F.; Fedorova, A.; Korablev, O. +3 more
SPICAV IR, one channel of SPICAV/SOIR instrument suite onboard Venus Express, performed solar occultation measurements of the atmosphere at terminators in 0.65-1.7 µm spectral range. We analyze the properties of the upper part of the Venus aerosol layer (upper haze, 70 - 95 km altitude) from 798 observations performed from May 2006 through N…
Testing the Distance Scale of the Gaia TGAS Catalogue by the Kinematic Method
Bobylev, V. V.; Bajkova, A. T.
We have studied the simultaneous and separate solutions of the basic kinematic equations obtained using the stellar velocities calculated on the basis of data from the Gaia TGAS and RAVE5 catalogues. By comparing the values of Ω'0 found by separately analyzing only the line-of-sight velocities of stars and only their proper motions, we …
Probing the Quiet Solar Atmosphere from the Photosphere to the Corona
Gontikakis, Costis; Tziotziou, Kostas; Kontogiannis, Ioannis +1 more
We investigate the morphology and temporal variability of a quiet-Sun network region in different solar layers. The emission in several extreme ultraviolet (EUV) spectral lines through both raster and slot time-series, recorded by the EUV Imaging Spectrometer (EIS) on board the Hinode spacecraft is studied along with Hα observations and high-resol…
Properties and relationship between solar eruptive flares and Coronal Mass Ejections during rising phase of Solar Cycles 23 and 24
Moon, Y. -J.; Shanmugaraju, A.; Umapathy, S. +2 more
Statistical relationship between major flares and the associated CMEs during rising phases of Solar Cycles 23 and 24 are studied. Totally more than 6000 and 10,000 CMEs were observed by SOHO/LASCO (Solar and Heliospheric Observatory/Large Angle Spectrometric Coronagraph) during 23rd [May 1996-June 2002] and 24th [December 2008-December 2014] solar…
Photometric Modeling and VIS-IR Albedo Maps of Tethys From Cassini-VIMS
Clark, R. N.; Stephan, K.; D'Aversa, E. +6 more
We report about the derivation of visible (VIS) and infrared (IR) albedo maps and spectral indicators of Saturn's satellite Tethys from the complete Cassini-Visual and Infrared Mapping Spectrometer (VIMS) data set. The application of a photometric correction is necessary to remove illumination and viewing effects from the I/F spectra, to compute s…
Three-dimensional density and compressible magnetic structure in solar wind turbulence
Narita, Yasuhito; Roberts, Owen W.; Escoubet, C. -Philippe
The three-dimensional structure of both compressible and incompressible components of turbulence is investigated at proton characteristic scales in the solar wind. Measurements of the three-dimensional structure are typically difficult, since the majority of measurements are performed by a single spacecraft. However, the Cluster mission consisting…
A search for polycyclic aromatic hydrocarbons over the Martian South Polar Residual Cap
Muller, J. -P.; Sidiropoulos, P.; Campbell, J. D.
We present our research on compositional mapping of the Martian South Polar Residual Cap (SPRC), especially the detection of organic signatures within the dust content of the ice, based on hyperspectral data analysis. The SPRC is the main region of interest for this investigation, because of the unique CO2 ice sublimation features that …