Search Publications
A dynamical study of the multiple system 17 Cygni ABFG
Romanenko, L. G.
Adynamical study of the relative motions of the components of the inner pairs AB (ADS 12913) and FG (ADS 12889) of the quadruple heirarchical system 17 Cygni (WDS 19464+3344) is presented, as well as analysis of themotions of the outer pair AB-FG. The study is based on CCD observations obtained on the 26-inch refractor of the Pulkovo Observatory (…
Compton thick absorber in type 1 quasar 3C 345 revealed by Suzaku and Swift/BAT
Eguchi, Satoshi
The archival data of 3C 345, a type 1 quasar at z = 0.5928, obtained with Suzaku and Swift/BAT are analysed. Though previous studies of this source applied only a simple broken power-law model, a heavily obscuring material is found to be required by considering Akaike information criteria. The application of the numerical torus model by Murphy &am…
Acceleration and particle transport in collisionless plasma in the process of dipolarization and nonstationary turbulence
Popov, V. Yu.; Petrukovich, A. A.; Zelenyi, L. M. +3 more
This work is devoted to studying the processes of the acceleration of plasma particles in thin current sheets that appear during magnetospheric substorms in the Earth's magnetosphere tail. A numerical model of magnetic dipolarization accompanied by plasma turbulence has been constructed and studied. The model allows one to investigate the particle…
A Simple Pile-up Model for Time Series Analysis
Sevilla, Diego J. R.
In this paper, a simple pile-up model is presented. This model calculates the probability P(n| N) of having n counts if N particles collide with a sensor during an exposure time. Through some approximations, an analytic expression depending on only one parameter is obtained. This parameter characterizes the pile-up magnitude, and depends on featur…
X-ray selection of Compton-Thick AGN at high redshift
Lanzuisi, G.
Compton-Thick (CT) active galactic nuclei (AGN) are a key ingredient of cosmic X-ray background (CXB) synthesis models, but are still an elusive component of the AGN population beyond the local universe. Multiwavelength surveys are the only way to find them at z > ∼ 0.1, and a deep X-ray coverage is crucial in order to clearly identify them amo…
On the nature of the candidate T-Tauri star V501 Aurigae★
Neuhäuser, R.; Ginski, C.; Mugrauer, M. +18 more
We report new multicolour photometry and high-resolution spectroscopic observations of the long-period variable V501 Aur, previously considered to be a weak-lined T-Tauri star belonging to the Taurus-Auriga star-forming region. The spectroscopic observations reveal that V501 Aur is a single-lined spectroscopic binary system with a 68.8-d orbital p…
Cassini UVIS observations of Titan ultraviolet airglow intensity dependence with solar zenith angle
West, R. A.; Esposito, L. W.; Royer, E. M. +3 more
The Cassini Ultraviolet Imaging Spectrometer (UVIS) observed the airglow (dayglow and nightglow) of Titan over a range of solar zenith angles (SZA) from 14 to 150° on five separate observations obtained between 2008 and 2012. The modeling of the solar cycle normalized UVIS observations indicates that a Chapman layer function provides a satisfactor…
Evolution of an equatorial coronal hole structure and the released coronal hole wind stream: Carrington rotations 2039 to 2050
Wimmer-Schweingruber, Robert F.; Berger, Lars; Heidrich-Meisner, Verena +2 more
Context. The Sun is a highly dynamic environment that exhibits dynamic behavior on many different timescales. Variability is observed both in closed and in open field line regions in the solar corona. In particular, coronal holes exhibit temporal and spatial variability. Signatures of these coronal dynamics are inherited by the coronal hole wind s…
X-ray study of extended emission around M 86 observed with Suzaku
Fujimoto, Ryuichi; Tanaka, Keigo; Hishi, Ukyo +4 more
We analyzed the Suzaku data of M 86 and its adjacent regions to study the extended emission around it. The M 86 core, the plume, and the tail extending toward the northwest were clearly detected, as well as the extended halo around them. From the position angle ∼ 45° to ∼ 275°, the surface brightness distribution of the core and the extended halo …
Nep-Akari Evolution with Redshift of Dust Attenuation in 8 ㎛ Selected Galaxies
Buat, V.; Burgarella, D.; Serjeant, S. +8 more
We built a 8um selected sample of galaxies in the NEP-AKARI field by defining 4 redshift bins with the four AKARI bands at 11, 15, 18 and 24 microns (0.15<z<0.49, 0.75<z<1.34, 1.34<z<1.7 and 1.7<z<2.05) . Our sample contains 4079 sources, 599 are securely detected with Herschel/PACS. Also adding ultraviolet (UV) data from G…