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Suzaku observations of Jovian diffuse hard X-ray emission
Miyoshi, Yoshizumi; Ezoe, Yuichiro; Ishikawa, Kumi +6 more
We report on results of systematic analyses of the entire three X-ray data sets of Jupiter taken by Suzaku in 2006, 2012, and 2014. Jovian diffuse hard X-ray emission was discovered by Suzaku in 2006 when the solar activity went toward its minimum. The diffuse emission was spatially consistent with the Jovian inner magnetosphere and was spectrally…
Dust dissipation timescales in the intermediate and outer regions of protoplanetary disks
Nakagawa, Takao; Kwon, Jungmi; Takita, Satoshi +2 more
Dust and gas in protoplanetary disks dissipate as central stars evolve. In order to estimate the dust dissipation timescales in the protoplanetary disks, we stacked the WISE 12 and 22, and the AKARI 90 µm survey images of known T Tauri stars and derived the average fluxes, well below the survey flux limit in the 90 µm band. We classifi…
X-Ray Flux and Spectral Variability of BL Lacertae Objects Mrk 421, Mrk 501, and 1ES1426+428 with Suzaku Satellite
Abdelbar, Ahmed M.; Beheary, M. M.; Saad, A. Ata +1 more
We present a detailed spectral study of Suzaku observations of three blazars (Mrk 421, Mrk 501, and 1ES1426+428). The X-ray properties of our sample are derived by extracting the BL Lacertae sample spectra, and fitted by five models. The fit was in the soft X-ray band (0.8 - 10.0 keV). These models give similar results. By comparing the fits from …
A Morphological Classification Model to Identify Unresolved PanSTARRS1 Sources. II. Update to the PS1 Point Source Catalog
Miller, A. A.; Hall, X. J.
We present an update to the PanSTARRS-1 Point Source Catalog (PS1 PSC), which provides morphological classifications of PS1 sources. The original PS1 PSC adopted stringent detection criteria that excluded hundreds of millions of PS1 sources from the PSC. Here, we adapt the supervised machine learning methods used to create the PS1 PSC and apply th…
Ripples, Transverse Aeolian Ridges, and Dark-Toned Sand Dunes on Mars: A Case Study in Terra Sabaea
Lu, Y.; Edgett, K. S.; Wu, Y. Z.
Ripples, transverse aeolian ridges (TARs), and dark-toned sand sheets and dunes are common aeolian bedforms on the Martian surface. They are important for understanding the nature of present-day Martian sediments and regional aeolian processes. Here we present a case study investigation of ripples, TARs, a dark-toned sand sheet, and dunes in an un…
HATS-34b and HATS-46b: re-characterization using TESS and Gaia
Hartman, Joel D.; Louden, Emma M.
We present a revised characterization of the previously discovered transiting planet systems HATS-34 and HATS-46. We make use of the newly available space-based light curves from the NASA TESS mission and high-precision parallax and absolute photometry measurements from the ESA Gaia mission to determine the mass and radius of the planets and host …
Spitzer Mid-infrared Study of Sh 2-208: Evolution of Protoplanetary Disks in Low-metallicity Environments
Yasui, Chikako
This study presents sensitive mid-infrared (MIR) photometry obtained with the Spitzer/IRAC for a young cluster in Sh 2-208 (S208) located in one of the lowest-metallicity H II regions in the Galaxy, $[{\rm{O}}/{\rm{H}}]=-0.8$ dex. Previous studies suggested that the cluster is ~0.5 Myr old and has a distance of D = 4 kpc, which is consistent with …
Energetic particle distributions in space physics represented by the Pearson differential equation for the kappa distribution
Shizgal, Bernie D.
The kappa distribution has been used for decades as a numerical fitting function to represent the energetic particle distributions measured with satellite instruments. The distributions are generally either a three dimensional distribution in the particle velocity or the one dimensional distribution in a velocity component in a particular directio…
Implications of the Low-frequency Turnover in the Spectrum of Radio Knot C in DG Tau
Björnsson, C. -I.
The synchrotron spectrum of radio knot C in the protostellar object DG Tau has a low-frequency turnover. This is used to show that its magnetic field strength is likely to be at least 10 mG, which is roughly two orders of magnitude larger than previously estimated. The earlier, lower value is due to an overestimate of the emission volume together …
Chandra X-Ray Observations of V830 Tau: A T Tauri Star Hosting an Evanescent Planet
Skinner, Stephen L.; Güdel, Manuel
The radial velocity study by Donati et al. (2016) reported the detection of a close-in giant planet in a 4.93 day orbit around the ~2 Myr old weak-lined T Tauri star V830 Tau. Because of the stringent timescale constraints that a very young host star like V830 Tau would place on hot-Jupiter formation models and inward-migration mechanisms, indepen…