Search Publications
Comprehensive Determination of the Hinode/EIS Roll Angle
Warren, Harry P.; Brooks, David H.; Baker, Deborah +5 more
We present a new coalignment method for the EUV Imaging Spectrometer (EIS) on board the Hinode spacecraft. In addition to the pointing offset and spacecraft jitter, this method determines the roll angle of the instrument, which has never been systematically measured, and which is therefore usually not corrected. The optimal pointing for EIS is com…
Seasonal variation of north-south asymmetry in the intensity of Saturn Kilometric Radiation from 2004 to 2017
Morioka, Akira; Tsuchiya, Fuminori; Misawa, Hiroaki +9 more
This study investigates the long-term variation of Saturn Kilometric Radiation (SKR) intensity observed by the Radio and Plasma Wave Science (RPWS) instrument on board the Cassini spacecraft from 2004 (southern summer) to 2017 (northern summer). The results show that the SKR intensity was brighter in the summer hemisphere than in the winter hemisp…
Data-driven stellar parameters for southern TESS FGK targets
Henning, Th; Deacon, N. R.; Kossakowski, D. E.
We present stellar parameter estimates for 939 457 southern FGK stars that are candidate targets for the Transiting Exoplanet Survey Satellite (TESS) mission. Using a data-driven method similar to the CANNON, we build a model of stellar colours as a function of stellar parameters. We then use these in combination with stellar evolution models to e…
Structure of Our Galactic Bulge from CN Measurements
Lee, Jae-Woo
The double red clumps (DRCs) are now dominantly believed to be the strong observational line of evidence of the so-called X-shaped Galactic bar structures. Recently, Lee et al. reported a subtle mean δCN(3839) difference between the DRCs and suggested a dichotomic picture that can be seen in globular clusters: the faint red clump is the first gene…
Cosmic Ray Modulation with the Maximum CME Speed Index During Solar Cycles 23 and 24
Kilcik, Ali; Sarp, Volkan; Yurchyshyn, Vasyl +2 more
We analyzed modulation of cosmic-ray intensities (CRIs) during Solar Cycles 23 and 24 by using the international sunspot numbers (ISSN) and the maximum CME speed index (MCMESI) as proxies for solar activity. Temporal variations, cross-correlations, and hysteresis patterns of CRI, MCMESI, and ISSN data were investigated. As a result, we concluded t…
Plasma Transport in Saturn's Low-Latitude Ionosphere: Cassini Data
Wahlund, J. -E.; Waite, J. H.; Cravens, T. E. +7 more
In 2017 the Cassini Orbiter made the first in situ measurements of the upper atmosphere and ionosphere of Saturn. The Ion and Neutral Mass Spectrometer in its ion mode measured densities of light ion species (H+, H2+, H3+, and He+), and the Radio and Plasma Wave Science instrument m…
Chemical Composition of Globular Clusters of Milky Way Subsystems from Gaia DR2 Data
Bobylev, V. V.; Bajkova, A. T.; Korchagin, V. I. +1 more
Results of a study of the kinematic and chemical properties of globular clusters of the Milky Way based on data from the Gaia DR2 catalog and meaurements with the Hubble Space Telescope are presented. A new method for dividing globular clusters into Galatic subsystems based on the elements of their Galactic orbits is proposed. Samples of globular …
A study of full space motions of outer Galactic disc A and F stars in two deep pencil beams
Monguió, M.; Harris, A.; Drew, J. E.
A and F stars can be used as probes of outer Galactic disc kinematics: here we extend the work of Harris et al. by cross-matching their A/F sample with Gaia DR2 to bring in proper motions. These are combined with the already measured radial velocities and spectrophotometric distances to obtain full space motions. We use this sample of 1173 stars, …
A revisit to the enigmatic variable star 21 Comae
Kallinger, Thomas; Pribulla, Theodor; Walczak, Przemysław +12 more
The magnetic chemically peculiar (Ap/CP2) star 21 Com has been extensively studied in the past, albeit with widely differing and sometimes contradictory results, in particular concerning the occurrence of short-term variability between about 5 to 90 min. We have performed a new investigation of 21 Com using Microvariability and Oscillations of Sta…
Concerning the occurrence of bow shocks around high-mass X-ray binaries
Prišegen, M.
Context. We investigate the occurrence of stellar bow shocks around high-mass X-ray binaries (HMXBs) in the Galaxy.
Aims: We seek to conduct a survey of HMXBs in the mid-infrared to search for the presence of bow shocks around these objects.
Methods: Telescopes operating in the mid-infrared, such as the Spitzer Space Telescope or Wide-fi…