Search Publications
Discovery of Redshifted He-like Iron Absorption Line from Luminous Accreting Neutron Star SMC X-1
Odaka, Hirokazu; Tamagawa, Toru; Nakano, Toshio +1 more
We have analyzed X-ray data of SMC X-1 obtained with Suzaku and discovered the combination of an absorption line and an underlying broadened emission line centered at 6.4 keV in an observation performed on 2012 May 19. This absorption line is centered at {6.61}-0.03+0.02 {keV} with an absorption strength of {5.9}-1.4
Microchannel Plate Efficiency to Detect Low Velocity Dust Impacts
James, David; Horányi, Mihály; Clark, George +2 more
Recent space experiments suggest that electron and ion energy analyzers using microchannel plates (MCPs) as detectors are also registering direct hits by nanodust particles. To allow the analysis and interpretation of these putative dust events, the detection efficiency of MCPs has to be characterized. We report on a series of experiments to inves…
Visual Orbit and Individual Masses of the Single-lined Spectroscopic Binary 94 AQR A (HD 219834A; MCA 74)
Docobo, José A.; Tamazian, Vakhtang S.; Campo, Pedro P. +1 more
By combining our improved visual orbit with the last spectroscopic solution of the single-lined spectroscopic binary, MCA 74 (ADS 16672Aa, Ab; HD 219834A), we derived its orbital solution to have a period of 6.321 years. Using the Gaia parallax, a systemic mass of 1.87 ± 0.09 {{ \mathcal M }}⊙ and a mass ratio of q = 0.725 were obtaine…
Thermal Evolution of the Nucleus of the Comet 67P for 120 Years: Numerical Simulations
Rusol, Andrey V.; Dorofeeva, Vera A.
The purpose of this paper is to estimate to what temperatures and to what depth the outer layers of the cometary nuclei are heated for several dozen revolutions around the Sun, and what changes in the composition of the volatiles occur in this case. This is important because it is not clear how much the experimentally obtained results on the compo…
The pc-scale radio structure of MIR-observed radio galaxies
Yuan, Ye; Gu, Min-Feng; Chen, Yong-Jun
We investigated the relationship between the accretion process and jet properties by utilizing very long baseline array (VLBA) and mid-infrared (MIR) data for a sample of 45 3CRR radio galaxies selected with a flux density at 178 MHz > 16.4 {Jy}, 5 GHz very large array (VLA) core flux density ≥ 7 {mJy} and MIR observations. The pc-scale radio s…
Propagating wave in active region-loops, located over the solar disk observed by the Interface Region Imaging Spectrograph
Zhang, J.; Zhang, B.; Hou, Y. J.
Aims: We aim to ascertain the physical parameters of a propagating wave over the solar disk detected by the Interface Region Imaging Spectrograph (IRIS).
Methods: Using imaging data from the IRIS and the Solar Dynamic Observatory (SDO), we tracked bright spots to determine the parameters of a propagating transverse wave in active region …
Gaia: 3-dimensional census of the Milky Way Galaxy
Gilmore, Gerard
Astrometry from space has unique advantages over ground-based observations: the all-sky coverage, relatively stable, and temperature and gravity invariant, operating environment delivers precision, accuracy and sample volume several orders of magnitude greater than ground-based results. Even more importantly, absolute astrometry is possible. The E…
Modeling, Analysis, and Interpretation of Photoelectron Energy Spectra at Enceladus Observed by Cassini
Schippers, P.; Coates, A. J.; Jones, G. H. +7 more
The Electron Spectrometer (ELS) of the Cassini Plasma Spectrometer has observed photoelectrons produced in the plume of Enceladus. These photoelectrons are observed during Enceladus encounters in the energetic particle shadow where the spacecraft is largely shielded from penetrating radiation by the moon. We present a complex electron spectrum at …
Collisional Heating of Interstellar Helium Flux at 1 AU
Gruntman, Mike
Because of relative motion of the local interstellar medium (LISM) with respect to the Sun, the interstellar wind, interstellar neutral helium atoms enter the heliosphere. Instruments on the Ulysses and Interstellar Boundary Explorer spacecraft measured directional dependencies of intensities, or sky maps, of helium atoms and determined the inters…
Far-infrared emission of massive stars
Krełowski, J.; Siebenmorgen, R.; Scicluna, P.
We present results of the analysis of a sample of 22 stars of spectral types from O7 to B5 and luminosity classes I-V for which spectra from the Infrared Spectrograph (IRS) of Spitzer are available. The IRS spectra of these stars are examined for signs of excess infrared (IR) emission by comparison with stellar atmospheric spectra. We find that th…