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Imaging Parity-violating Modes in the CMB
Contaldi, Carlo R.
Correlations of polarization components in the coordinate frame are a natural basis for searches of parity-violating modes in the cosmic microwave background. This fact can be exploited to build estimators of parity-violating modes that are local and robust with respect to partial-sky coverage or inhomogeneous weighting. As an example application …
Colour gradients in cluster ellipticals at z ∼ 1.4: the hidden content of the galaxy central regions
Gargiulo, A.; Saracco, P.; De Propris, R. +1 more
We present F775W-F850LP (rest-frame UV - U) and F850LP-F160W (rest-frame U - R) colour gradients for a sample of 17 elliptical galaxies morphologically selected in the cluster XMMU J2235.3-2557 at z = 1.39. We detected significant negative (redder inwards) U - R colour gradients in ∼70 per cent of the galaxies and flat gradients for the remaining …
Cosmological N-body simulations with generic hot dark matter
Brandbyge, Jacob; Hannestad, Steen
We have calculated the non-linear effects of generic fermionic and bosonic hot dark matter components in cosmological N-body simulations. For sub-eV masses, the non-linear power spectrum suppression caused by thermal free-streaming resembles the one seen for massive neutrinos, whereas for masses larger than 1 eV, the non-linear relative suppressio…
Measuring the Sun's motion with stellar streams
Malhan, Khyati; Ibata, Rodrigo A.
We present a method for measuring the Sun's motion using the proper motions of Galactic halo star streams. The method relies on the fact that the motion of the stars perpendicular to a stream from a low-mass progenitor is close to zero when viewed from a non-rotating frame at rest with respect to the Galaxy, and that the deviation from zero is due…
Observations of the γ-ray pulsar J1932+1916 in X-rays
Shternin, P.; Zyuzin, D.; Danilenko, A. +2 more
We present the analysis of the archival Suzaku and Swift X-ray observations of the young γ-ray pulsar J1932+1916 field. The data revealed a point-like object at the γ-ray position of the pulsar and diffuse X-ray emission around it. Spectra of the point-like source and diffuse emission are well-described by absorbed power-law models with spectral p…
On a correlation among azimuthal velocities and the flyby anomaly sign
Acedo, L.; Bel, Ll.
Data of six flybys, those of Galileo I, Galileo II, NEAR, Cassini, Rosetta, and Messenger were reported by Anderson et al. (2008). Four of them: Galileo I, NEAR, Rosetta, and Messenger gain Newtonian energy during the flyby transfer, while Galileo II and Cassini lose energy. In both cases this is a surprising anomaly since Newtonian forces origina…
Optical spectroscopy of candidates for quasars at 3 < z < 5.5 from the XMM-newton X-ray survey. A distant X-ray quasar at z = 5.08
Sazonov, S. Yu.; Eselevich, M. V.; Khorunzhev, G. A. +2 more
We present the results of optical spectroscopy for 19 quasar candidates at photometric redshifts z phot ≳ 3, 18 of which enter into the Khorunzhev et al. (2016) catalog (K16). This is a catalog of quasar candidates and known type 1 quasars selected among the X-ray sources of the 3XMM-DR4 catalog of the XMM-Newton serendipitous survey. W…
The nature of X-ray spectral variability in MCG-6-30-15
Papadakis, I. E.; Kammoun, E. S.
The flux-flux plot (FFP) method can provide model-independent clues regarding the X-ray variability of active galactic nuclei. To use it properly, the bin size of the light curves should be as short as possible, provided the average counts in the light-curve bins are larger than ∼200. We apply the FFP method, performed in 2013, to the simultaneous…
Multiple X-ray bursts and the model of a spreading layer of accreting matter over the neutron star surface
Grebenev, S. A.; Chelovekov, I. V.
We report the detection of series of close type I X-ray bursts consisting of two or three events with a recurrence time much shorter than the characteristic (at the observed mean accretion rate) time of matter accumulation needed for a thermonuclear explosion to be initiated on the neutron star surface during the JEM-X/INTEGRAL observations of sev…
Vertical Thermospheric Density Profiles From EUV Solar Occultations Made by PROBA2 LYRA for Solar Cycle 24
Dominique, M.; Eparvier, F. G.; Thiemann, E. M. B. +1 more
A new data set of summed neutral N2 and O number density profiles, spanning altitudes between 150 and 400 km, and observed during Northern Winter from 2010 to 2016 is presented. The neutral density profiles are derived from solar occultation measurements made by the 0.1-20 nm Zr channel on the Large Yield Radiometer (LYRA) instrument on…