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Wind mass transfer in S-type symbiotic binaries. II. Indication of wind focusing
Skopal, A.; Shagatova, N.; Cariková, Z.
Context. The wind mass transfer from a giant to its white dwarf companion in symbiotic binaries is not well understood. For example, the efficiency of wind mass transfer of the canonical Bondi-Hoyle accretion mechanism is too low to power the typical luminosities of the accretors. However, recent observations and modelling indicate a considerably …
The Wide-angle Outflow of the Lensed z = 1.51 AGN HS 0810+2554
Cappi, M.; Chartas, G.; Giustini, M. +4 more
We present results from X-ray observations of the gravitationally lensed z = 1.51 active galactic nucleus (AGN) HS 0810+2554 performed with the Chandra X-ray Observatory and XMM-Newton. Blueshifted absorption lines are detected in both observations at rest-frame energies ranging between ∼1 and 12 keV at ≳99% confidence. The inferred velocities of …
Photometric and Astrometric Vagaries of the Enigma Star KIC 8462852
Makarov, Valeri V.; Goldin, Alexey
We apply a principal component analysis (PCA)-based pre-whitening method to the entire collection of main Kepler mission long-cadence data for KIC 8462852 spanning four years. This technique removes the correlated variations of instrumental origin in both the detected light curves and astrometry, resolving intrinsic changes in flux and image posit…
Hubble and Keck Telescope Observations of Active Asteroid 288P/300163 (2006 VW139)
Mutchler, Max; Jewitt, David; Agarwal, Jessica +2 more
We present Hubble Space Telescope (HST) and Keck 10 m telescope observations of active asteroid 288P/300163 (2006 VW139) taken to examine ejected dust. The nucleus is a C-type object with absolute magnitude HV = 17.0 ± 0.1 and estimated diameter ∼2.6 km (for assumed visual geometric albedo pV = 0.04). Variations in the bright…
Testing gravity at large scales with H I intensity mapping
Pourtsidou, Alkistis
We investigate the possibility of testing Einstein's general theory of relativity (GR) and the standard cosmological model via the EG statistic using neutral hydrogen (H I) intensity mapping. We generalize the Fourier space estimator for EG to include H I as a biased tracer of matter and forecast statistical errors using H I …
Richness-based masses of rich and famous galaxy clusters
Andreon, S.
We present a catalog of galaxy cluster masses derived by exploiting the tight correlation between mass and richness, I.e., a properly computed number of bright cluster galaxies. The richness definition adopted in this work is properly calibrated, shows a small scatter with mass, and has a known evolution, which means that we can estimate accurate …
Modified ion-Weibel instability as a possible source of wave activity at Comet 67P/Churyumov-Gerasimenko
Motschmann, Uwe; Glassmeier, Karl-Heinz; Meier, Patrick
We analytically discuss wave excitation in a homogeneous three component plasma consisting of solar wind protons, electrons and a beam of cometary water ions applied to the plasma environment of comet 67P/Churyumov-Gerasimenko. The resulting dispersion relations are studied in a solar wind rest frame, where a cometary current is solely generated b…
Giant lobes of Centaurus A as seen in radio and γ-ray images obtained with the Fermi-LAT and Planck satellites
Aharonian, Felix; Yang, Rui-zhi; Sun, Xiao-na +1 more
The γ-ray data of Fermi-LAT on the giant lobes of Centaurus A are analysed together with the high frequency radio data obtained with the Planck satellite. The large γ-ray photon statistics, accumulated during seven years of observations, and the recently updated Fermi-LAT collaboration software tools allow substantial extension of the detected γ-r…
A high mass progenitor for the Type Ic Supernova 2007gr inferred from its environment
Ramirez-Ruiz, Enrico; Maund, Justyn R.
We present an analysis of late-time Hubble Space Telescope Wide Field Camera 3 (WFC3) and Wide Field Planetary Camera 2 (WFPC2) observations of the site of the Type Ic supernova (SN) 2007gr in NGC 1058. The SN is barely recovered in the late-time WFPC2 observations, while a possible detection in the later WFC3 data is debatable. These observations…
Examining molecular clouds in the Galactic Centre region using X-ray reflection spectra simulations
Terrier, R.; Goldwurm, A.; Chernyakova, M. +1 more
In the centre of our Galaxy lies a supermassive black hole, identified with the radio source Sagittarius A⋆. This black hole has an estimated mass of around 4 million solar masses. Although Sagittarius A⋆ is quite dim in terms of total radiated energy, having a luminosity that is a factor of 1010 lower than its Edd…