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23 GHz VLBI Observations of SN 2008ax
(EDP Sciences, 2009)
We report on phase-referenced 23 GHz Very-Long-Baseline-Interferometry (VLBI) observations of the type IIb supernova SN 2008ax, made with the Very Long Baseline Array (VLBA) on 2 April 2008 (33 days after explosion). These ...
A Decade of SN 1993J: Discovery of Radio Wavelength Effects in the Expansion Rate
(EDP Sciences, 2009)
We studied the growth of the shell-like radio structure of supernova SN 1993J in M 81 from September 1993 to October 2003 with very-long-baseline interferometry (VLBI) observations at the wavelengths of 3.6, 6, and 18 cm. ...
Second and Third Season QUaD Cosmic Microwave Background Temperature and Polarization Power Spectra
(IOP Publishing, 2009)
We report results from the second and third seasons of observation with the QUaD experiment. Angular power spectra of the cosmic microwave background are derived for both temperature and polarization at both 100 GHz and ...
Infall and Outflow of Molecular Gas in Sgr B2
(American Astronomical Society, 2008)
Observations of two \(H_2CO (3_{03}-2_{02} and 3_{21}-2_{20})\) lines and continuum emission at 1.3 mm toward Sgr B2(N) and Sgr B2(M) have been carried out with the SMA. The mosaic maps of Sgr B2(N) and Sgr B2(M) in both ...
Parity Violation Constraints Using Cosmic Microwave Background Polarization Spectra from 2006 and 2007 Observations by the QUaD Polarimeter
(American Physical Society, 2009)
We constrain parity-violating interactions to the surface of last scattering using spectra from the QUaD experiment’s second and third seasons of observations by searching for a possible systematic rotation of the polarization ...
Energy Relaxation In Collisions Of Hydrogen And Deuterium With Oxygen Atoms
(American Geophysical Union, 2009)
Collision energy transfer processes between hydrogen, deuterium, and oxygen atoms in the upper atmospheres of the terrestrial planets are studied. A new set of interaction potentials has been constructed using an accurate ...
The Solar Wind Charge-eXchange Contribution to the Local Soft X-ray Background: Model to Data Comparison in the 0.1-1.0 keV Band
(Springer Verlag, 2008)
The major sources of the Soft X-ray Background (SXRB), besides distinct structures as supernovae and superbubbles (e.g. Loop I), are: (i) an absorbed extragalactic emission following a power law, (ii) an absorbed thermal ...
A Turbulent Model of Gamma-Ray Burst Variability
(Royal Astronomical Society, 2009)
A popular paradigm to explain the rapid temporal variability observed in gamma-ray burst (GRB) light curves is the internal shock model. We propose an alternative model in which the radiating fluid in the GRB shell is ...
Collision-Induced Spin Exchange of Alkali-Metal Atoms With \(^3\)He: An Ab Initio Study
(American Physical Society, 2009)
We present a rigorous quantum study of spin-exchange transitions in collisions of the alkali-metal atoms
with \(^3\)He in the presence of an external magnetic field. Using accurate ab initio interaction potentials, we ...
Scattering of \(Yb\) and \(Yb^+\)
(American Physical Society, 2009)
We calculate the cross sections for scattering of a neutral ytterbium atom with its positive ion at energies up to 30 eV. We identify peaks in the forward direction as arising from elastic collisions and those in the ...