Search Publications
Buoyancy-driven inflow to a relic cold core: the gas belt in radio galaxy 3C 386
Birkinshaw, M.; Worrall, D. M.; Kraft, R. P. +1 more
We report measurements from an XMM-Newton observation of the low-excitation radio galaxy 3C 386. The study focusses on an X-ray-emitting gas belt, which lies between and orthogonal to the radio lobes of 3C 386 and has a mean temperature of 0.94 ± 0.05 keV, cooler than the extended group atmosphere. The gas in the belt shows temperature structure w…
Ducted electromagnetic waves in the Martian ionosphere detected by the Mars Advanced Radar for Subsurface and Ionosphere Sounding radar
Huang, Qian; Zhang, Jie; Orosei, Roberto +1 more
In the data of the Mars Advanced Radar for Subsurface and Ionosphere Sounding on board the European Space Agency (ESA) mission Mars Express (MEX), a distinctive type of signals (called the "epsilon signature"), which is similar to that previously detected during radio sounding of the terrestrial F region ionosphere, is found. The signature is inte…
The complex high-mass star-forming region IRAS 15507-5359
Roth, M.; Elia, D.; Persi, P. +2 more
The far-infrared IRAS 15507-5359 source is known to be a medium-mass star-forming region associated with a compact H II region and a near-infrared embedded cluster. We present a survey of infrared-calibrated images ranging from 1.2 to 500 µm obtained with the Baade telescope at Las Campanas Observatory, and the Herschel space telescope with …
Classification of CMEs Based on Their Dynamics
Michalek, G.; Nicewicz, J.
A large set of coronal mass ejections CMEs (6621) has been selected to study their dynamics seen with the Large Angle and Spectroscopic Coronagraph (LASCO) onboard the Solar and Heliospheric Observatory (SOHO) field of view (LFOV). These events were selected based on having at least six height-time measurements so that their dynamic properties, in…
Variations of the X-ray INTEGRAL spectrum of the active galactic nucleus of NGC 4945
Fedorova, E. V.; Zhdanov, V. I.
Results of 11-year-long X-ray INTEGRAL observations of the nucleus of Seyfert galaxy NGC 4945 in the 3–500 keV range were processed. A two-component spectrum model, which includes strong radiation absorption in the Compton-thick torus around the AGN "central engine" and secondary radiation reflected from the torus walls, was used in the analysis. …
Transient X-Ray Source Population in the Magellanic-type Galaxy NGC 55
Jithesh, V.; Wang, Zhongxiang
We present the spectral and temporal properties of 15 candidate transient X-ray sources detected in archival XMM-Newton and Chandra observations of the nearby Magellanic-type, SB(s)m galaxy NGC 55. Based on an X-ray color classification scheme, the majority of the sources may be identified as X-ray binaries (XRBs), and six sources are soft, includ…
Gaia-GOSA: A Collaborative Service for Asteroid Observers
Santana-Ros, Toni; Marciniak, Anna; Bartczak, Prezemyslaw
We describe the Gaia-Ground-based Observational Service for Asteroids (Gaia-GOSA), which is a website aiming to facilitate asteroid observers in contributing to the Gaia mission by gathering lightcurves of selected targets. GOSA users can plan their observing runs by selecting the visible targets for a given date, collaborate with other observers …
Photoionization Modeling of the Low-luminosity Seyfert 1 Nucleus in NGC 3516
Devereux, Nick
Spectroscopic observations of the low-luminosity Seyfert 1 nucleus in NGC 3516 obtained with the Hubble Space Telescope show that the visible spectrum is dominated by Balmer emission lines of hydrogen (H) and a continuum luminosity that rises into the UV. The anomalous {{H}}α /Hβ emission line ratio, the Balmer emission line luminosity, and the di…
Spin State Estimation of Tumbling Small Bodies
Bhaskaran, Shyam; Olson, Corwin; Russell, Ryan P.
It is expected that a non-trivial percentage of small bodies that future missions may visit are in non-principal axis rotation (i.e. "tumbling"). The primary contribution of this paper is the application of the Extended Kalman Filter (EKF) Simultaneous Localization and Mapping (SLAM) method to estimate the small body spin state, mass, and moments …
Star formation in a diffuse high-altitude cloud?
Kerp, J.; Lenz, D.; Röhser, T.
Context. A recent discovery of two stellar clusters associated with the diffuse high-latitude cloud HRK 81.4-77.8 has important implications for star formation in the Galactic halo.
Aims: We derive a plausible distance estimate to HRK 81.4-77.8 primarily from its gaseous properties.
Methods: We spatially correlate state-of-the-art HI, fa…