Search Publications
Study of Mars Magnetosheath Fluctuations using the Kurtosis Technique: Mars Express Observations
Fraenz, M.; Bolzan, M. J. A.; Echer, E. +1 more
Reconstructing AGN X-ray spectral parameter distributions with Bayesian methods. II. Population inference
Paltani, Stéphane; Salvato, Mara; Eckert, Dominique +1 more
We present a new Bayesian method for reconstructing the parent distributions of X-ray spectral parameters of active galactic nuclei (AGN) in large surveys. The method uses the probability distribution function (PDF) of posteriors obtained by fitting a consistent physical model to each object with a Bayesian method. The PDFs are often broadly distr…
Herschel discovery of far-infrared emission from the hotspot D in the radio galaxy Cygnus A
Isobe, Naoki; Tashiro, Makoto S.; Sunada, Yuji +3 more
The far-infrared counterpart of hotspot D, the terminal hotspot of the eastern jet hosted by the radio galaxy Cygnus A, is detected with Herschel Aperture photometry of the source performed in 5 photometric bands covering the wavelength range of 70-350 $\mu$m. After removing the contamination from another nearby hotspot, E, the far-infrared intens…
Fast prograde coronal flows in solar active regions
Chamberlin, Phillip C.; Fletcher, Lyndsay; Mulay, Sargam M. +6 more
We report the discovery and characterization of high-speed (>100 km s-1) horizontal flows in solar active regions, making use of the Sun-as-a-star spectroscopy in the range 5-105 nm provided by the EVE (Extreme Ultraviolet Variability Experiment) spectrometers on the Solar Dynamics Observatory. These apparent flows are persistent on …
Toward Understanding the B[e] Phenomenon. IX. Nature and Binarity of MWC645
Miroshnichenko, A. S.; Manset, N.; Zharikov, S. V. +14 more
We present the results of optical and near-IR spectroscopy and multicolor photometry of the emission-line star MWC 645, which exhibits the B[e] phenomenon. The presence of positionally variable absorption lines of a cool star detected for the first time indicates that the object is a binary system. Using a combination of the photometric and spectr…
Chandra revisits WR 48a: testing colliding wind models in massive binaries
Skinner, Stephen L.; Zhekov, Svetozar A.; Gagné, Marc
We present results of new Chandra High-Energy Transmission Grating (HETG) observations (2019 November-December) of the massive Wolf-Rayet binary WR 48a. Analysis of these high-quality data showed that the spectral lines in this massive binary are broadened (full width at half-maximum, FWHM = 1400 km s-1) and marginally blueshifted (~-10…
Subpixel-Scale Topography Retrieval of Mars Using Single-Image DTM Estimation and Super-Resolution Restoration
Tao, Yu; Michael, Greg; Muller, Jan-Peter +5 more
We propose using coupled deep learning based super-resolution restoration (SRR) and single-image digital terrain model (DTM) estimation (SDE) methods to produce subpixel-scale topography from single-view ESA Trace Gas Orbiter Colour and Stereo Surface Imaging System (CaSSIS) and NASA Mars Reconnaissance Orbiter High Resolution Imaging Science Expe…
Study of Complex Absorption and Reflection in a Unique Intermediate Polar Paloma
Dutta, Anirban; Rana, Vikram
We present the broadband (0.3-40.0 keV) X-ray analysis of a unique intermediate polar Paloma using simultaneous data from XMM-Newton and NuSTAR observatories. The X-ray power spectra show strong modulations over orbital period compared to spin period. The orbit-folded light curves show a single broad hump-like structure with strong dips for soft t…
Characterizing X-ray activity cycles of young solar-like stars with solar observations
Stelzer, Beate; Orlando, Salvatore; Coffaro, Martina
Throughout an activity cycle, magnetic structures rise to the stellar surface, evolve and decay. Tracing their evolution on a stellar corona allows us to characterize the X-ray cycles. However, directly mapping magnetic structures is feasible only for the Sun, while such structures are spatially unresolved with present-day X-ray instruments on ste…
Simultaneous X-ray/UV Observations of Ultraluminous X-ray Source Holmberg II X-1 with Indian Space Mission Astrosat
Vinokurov, A.; Solovyeva, Y.; Atapin, K. +11 more
We present the results of eight epochs of simultaneous UV and X-ray observations of the highly variable ultraluminous X-ray source (ULX) Holmberg II X-1 with AstroSat—Indian multiwavelength space satellite. During the entire observation period from late 2016 to early 2020, Holmberg II X-1 showed a moderate X-ray luminosity about of