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Using a combination of automated diffraction tomography and precession electron diffraction techniques, quasi-kinematical electron diffraction data sets were collected from intermetallic Ni1+xTe1 embedded nanodomains and ion-thinned specimens of 6H-SiC semiconductor. Cell parameters and space groups were found automatically from the reconstructed 3D diffraction volume. The extracted intensities were used for fast ab initio structure determination by direct methods. [ABSTRACT FROM AUTHOR]

We have analyzed a ∼130 ks XMM-Newton observation of the dynamically confirmed black hole + Wolf-Rayet (BH+WR) X-ray binary (XB) IC10 X-1, covering ∼1 orbital cycle. This system experiences periodic intensity dips every ∼35 hr. We find that energy-independent evolution is rejected at a >5σ level. The spectral and timing evolution of IC10 X-1 are best explained by a compact disk blackbody and an extended Comptonized component, where the thermal component is completely absorbed and the Comptonized component is partially covered during the dip. We consider three possibilities for the absorber: cold material in the outer accretion disk, as is well documented for Galactic neutron star (NS) XBs at high inclination; a stream of stellar wind that is enhanced by traveling through the L1 point; and a spherical wind. We estimated the corona radius (rADC) for IC10 X-1 from the dip ingress to be ∼106 km, assuming absorption from the outer disk, and found it to be consistent with the relation between rADC and 1-30 keV luminosity observed in Galactic NS XBs that spans two orders of magnitude. For the other two scenarios, the corona would be larger. Prior BH mass (MBH) estimates range over 23-38 M☼, depending on the inclination and WR mass. For disk absorption, the inclination, i, is likely to be ∼60-80°, with MBH ∼ 24-41 M☼. Alternatively, the L1-enhanced wind requires i ∼ 80°, suggesting ∼24-33 M☼. For a spherical absorber, i ∼ 40°, and MBH ∼ 50-65 M☼. [ABSTRACT FROM AUTHOR]

Extended gas clouds have been previously detected surrounding the brightest known close-in transiting hot Jupiter exoplanets, HD 209458 b and HD 189733 b; we observed the distant but more extreme close-in hot Jupiter system, WASP-12, with Hubble Space Telescope (HST). Near-UV (NUV) transits up to three times deeper than the optical transit of WASP-12 b reveal extensive diffuse gas, extending well beyond the Roche lobe. The distribution of absorbing gas varies between visits. The deepest NUV transits are at wavelength ranges with strong stellar photospheric absorption, implying that the absorbing gas may have temperature and composition similar to those of the stellar photosphere. Our spectra reveal significantly enhanced absorption (greater than 3σ below the median) at ∼200 individual wavelengths on each of two HST visits; 65 of these wavelengths are consistent between the two visits, using a strict criterion for velocity matching that excludes matches with velocity shifts exceeding ∼20 km s–1. Excess transit depths are robustly detected throughout the inner wings of the Mg II resonance lines independently on both HST visits. We detected absorption in Fe II λ2586, the heaviest species yet detected in an exoplanet transit. The Mg II line cores have zero flux, emission cores exhibited by every other observed star of similar age and spectral type are conspicuously absent. WASP-12 probably produces normal Mg II profiles, but the inner portions of these strong resonance lines are likely affected by extrinsic absorption. The required Mg+ column is an order of magnitude greater than expected from the interstellar medium, though we cannot completely dismiss that possibility. A more plausible source of absorption is gas lost by WASP-12 b. We show that planetary mass loss can produce the required column. Our Visit 2 NUV light curves show evidence for a stellar flare. We show that some of the possible transit detections in resonance lines of rare elements may be due instead to non-resonant transitions in common species. We present optical observations and update the transit ephemeris. [ABSTRACT FROM AUTHOR]