5,062 research outputs found
Electroweak radiative corrections to triple photon production at the ILC
In this paper, we present the precision predictions for three photon
production in the standard model (SM) at the ILC including the full
next-to-leading (NLO) electroweak (EW) corrections, high order initial state
radiation (h.o.ISR) contributions and beamstrahlung effects. We present the LO
and the NLO EW+h.o.ISR+beamstrahlung corrected total cross sections for various
colliding energy when and the kinematic
distributions of final photons with at ILC, and find
that the NLO EW corrections, the h.o.ISR contributions and the beamstrahlung
effects are important in exploring the process .Comment: 6 pages, 8 figures, accepted for publication in Physics Letters
Density Functional Study of Excess Fe in FeTe: Magnetism and Doping
The electronic and magnetic properties of the excess Fe in iron telluride
FeTe are investigated by density functional calculations. We find
that the excess Fe occurs with valence near Fe, and therefore provides
electron doping with approximately one carrier per Fe, and furthermore that the
excess Fe is strongly magnetic. Thus it will provide local moments that
interact with the plane Fe magnetism, and these are expected to persist in
phases where the magnetism of the planes is destroyed for example by pressure
or doping. These results are discussed in the context of superconductivity
Empirical metallicity-dependent calibrations of effective temperature against colours for dwarfs and giants based on interferometric data
We present empirical metallicity-dependent calibrations of effective
temperature against colours for dwarfs of luminosity classes IV and V and for
giants of luminosity classes II and III, based on a collection from the
literature of about two hundred nearby stars with direct effective temperature
measurements of better than 2.5 per cent. The calibrations are valid for an
effective temperature range 3,100 - 10,000 K for dwarfs of spectral types M5 to
A0 and 3,100 - 5,700 K for giants of spectral types K5 to G5. A total of
twenty-one colours for dwarfs and eighteen colours for giants of bands of four
photometric systems, i.e. the Johnson (), the Cousins
(), the Sloan Digital Sky Survey (SDSS, ) and the Two
Micron All Sky Survey (2MASS, ), have been calibrated. Restricted
by the metallicity range of the current sample, the calibrations are mainly
applicable for disk stars ([Fe/H]). The normalized percentage
residuals of the calibrations are typically 2.0 and 1.5 per cent for dwarfs and
giants, respectively. Some systematic discrepancies at various levels are found
between the current scales and those available in the literature (e.g. those
based on the infrared flux method IRFM or spectroscopy). Based on the current
calibrations, we have re-determined the colours of the Sun. We have also
investigated the systematic errors in effective temperatures yielded by the
current on-going large scale low- to intermediate-resolution stellar
spectroscopic surveys. We show that the calibration of colour ()
presented in the current work provides an invaluable tool for the estimation of
stellar effective temperature for those on-going or upcoming surveys.Comment: 28 pages, 19 figures, 8 tables, accepted for publication in MNRA
Bis(2-methoxyÂphenolato-κ2 O,O′)copper(II)
In the title compound, [Cu(C7H7O2)2], the asymmetric unit contains one and a half molecules with the central Cu(II) atoms situated on a general position and on a centre of inversion, respectively. Both Cu(II) atoms show a similar slightly distorted square-planar coordination, resulting from four O atoms of two 2-methoxyphenolate anions
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