Search Publications
Reducing loss of significance in the computation of Earth-based two-way Doppler observables for small body missions
Li, Fei; Ye, Mao; Barriot, Jean-Pierre +5 more
Two-way Doppler measurement is a typical Earth-based radiometric technique for interplanetary spacecraft navigation and gravity science investigation. The most widely used model for the computation of two-way Doppler observables is Moyer's differenced-range Doppler (DRD) formula, which is based on a Schwarzschild approximation of the Solar-System …
Absolute parameters of young stars: PU Pup
Erdem, Ahmet; Sürgit, Derya; Budding, Edwin +2 more
We present combined photometric and spectroscopic analyses of the southern binary star PU Pup. High-resolution spectra of this system were taken at the University of Canterbury Mt. John Observatory in the years 2008 and again in 2014-2015. We find the light contribution of the secondary component to be only ~2% of the total light of the system in …
Photometric and period analysis of the eclipsing binary system V2783 Ori
Bulut, İ.; Bulut, A.
In this study we performed the first detailed photometric and period analysis of the recently discovered eclipsing binary star V2783 Ori. The analysis of the light curve has shown that the system is in a detached configuration, with the orbital eccentricity e = 0.274 ± 0.008. The photometric mass ratio of V2783 Ori determined from the light curve …
Search for Magnetars in the Galaxy M31 as Periodic X-ray Sources Based on XMM-Newton Data
Popov, S. B.; Pshirkov, M. S.; Zolotukhin, I. Yu.
Several years ago a series of powerful millisecond radio bursts with close dispersion measures was detected toward the galaxy M31. Taking the hypothesis about the possible association of these radio bursts with a magnetar in M31 as a starting point, we have searched for periodic X-ray signal sources using data from the XMM-Newton X-ray telescope. …
The Evolution of the Luminosity Function for Luminous Compact Blue Galaxies to z = 1
Pisano, D. J.; Bershady, M. A.; Crawford, S. M. +2 more
Luminous compact blue galaxies (LCBGs) are compact, star-forming galaxies that are rarely observed in the local universe but abundant at z = 1. This increase in LCBG number density over cosmic lookback time roughly follows the increase in the star formation rate density of the universe over the same period. We use publicly available data in the CO…
Dynamics of material ejected from the Hatmehit depression and landslides on comet 67P/Churyumov-Gerasimenko
Czechowski, Leszek; Kossacki, Konrad J.
In this work we investigate trajectories and regions of deposition of material ejected from depression Hatmehit on comet 67P/Churyumov-Gerasimenko. This depression, located on the lobe Head, could be a result of endogenic, possibly still ongoing, activity. We calculated trajectories of the ejecta with different initial velocities and we determined…
On Charon's Far-ultraviolet Surface Reflectance
Parker, Joel Wm.; Stern, S. Alan; Verbiscer, Anne J. +3 more
We present the first measurements of Charon's far-ultraviolet (FUV) surface reflectance, obtained by the Alice spectrograph on New Horizons. We find no measurable flux shortward of 1650 Å, and Charon's geometric albedo is <0.019 (3σ) at 1600 Å. From 1650 to 1725 Å, Charon's geometric albedo increases to 0.166 ± 0.068 and remains nearly constant…
The SIXS Instrument on Bepicolumbo, and Its Use for Space Weather Observations, and in Conjunction with MIXS
Muinonen, Karri; Huovelin, Juhani; Bunce, E. +2 more
The Solar Intensity X-ray and particle Spectrometer (SIXS) on BepiColumbo Mercury Planetary Orbiter (MPO) will investigate the direct solar X-rays and protons and electrons which pass the spacecraft on their way to Mercury. It has an innovative compact design, and the Mercury Imaging X-ray Spectrometer, with which it is paired, is similarly highly…
Infrared Emission Properties of Active Galactic Nuclei from Swift-BAT Hard X-Ray Survey
Yang, Xiao-Hong
The Swift/Burst Alert Telescope (BAT) 105-month survey detected 1632 hard X-ray sources in the 14-195 keV band, which includes 1105 active galactic nuclei (AGNs) that are unbiased against Compton-thin obscuration. We use a series of two-color diagrams to analyze the near, mid (MIR), and far-infrared properties of the Swift/BAT AGNs, based on data …
In Which Magnetotail Hemisphere is a Satellite? Problems Using in Situ Magnetic Field Data
Gunell, H.; Hamrin, M.; Pitkänen, T. +2 more
In Earth's magnetotail plasma sheet, the sunward tailward Bx component of the magnetic field is often used to separate the region above and below the cross tail current sheet. Using a three dimensional magneto hydrodynamic simulation, we show that high speed flows do not only affect the north south magnetic field component (causing dipo…