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The Equity Premium
Recent research on the equity risk premium has questioned the ability of historical
estimates of the risk premium to provide reliable estimates of the expected risk
premium. We calculate the equity risk premium for a number of countries over longer
horizons than has been attempted to date. We show that the realised US equity
premium is consistent with the premia obtained elsewhere. Furthermore, using well
over a century of data, we find that current estimates of the equity premia are close to
those observed during the pre-1914 era. This is of particular relevance given the
argument that the financial environment during that period bears a closer resemblance
to today than the 1914-1945 period, and possibly also the 1945-1971 period. This
points to a current equity risk premium that is considerably lower than consensus
forecasts (Welch 2001)
Vibrational excitation of diatomic molecular ions in strong-field ionization of diatomic molecules
A model based on the strong-field and Born-Oppenheimer approximations
qualitatively describes the distribution over vibrational states formed in a
diatomic molecular ion following ionization of the neutral molecule by intense
laser pulses. Good agreement is found with a recent experiment [X. Urbain et
al., Phys. Rev. Lett. 92, 163004 (2004)]. In particular, the observed deviation
from a Franck-Condon-like distribution is reproduced. Additionally, we
demonstrate control of the vibrational distribution by a variation of the peak
intensity or a change of frequency of the laser pulse.Comment: 4 pages, 4 figure
Manipulating the torsion of molecules by strong laser pulses
A proof-of-principle experiment is reported, where torsional motion of a
molecule, consisting of a pair of phenyl rings, is induced by strong laser
pulses. A nanosecond laser pulse spatially aligns the carbon-carbon bond axis,
connecting the two phenyl rings, allowing a perpendicularly polarized, intense
femtosecond pulse to initiate torsional motion accompanied by an overall
rotation about the fixed axis. The induced motion is monitored by femtosecond
time-resolved Coulomb explosion imaging. Our theoretical analysis accounts for
and generalizes the experimental findings.Comment: 4 pages, 4 figures, submitted to PRL; Major revision of the
presentation of the material; Correction of ion labels in Fig. 2(a
NuSTAR Observations of G11.2–0.3
We present in this paper the hard X-ray view of the pulsar wind nebula in G11.2−0.3 and its central pulsar powered pulsar J1811−1925 as seen by NuSTAR. We complement the data with Chandra for a more complete picture and confirm the existence of a hard, power-law component in the shell with photon index Γ = 2.1 ± 0.1, which we attribute to synchrotron emission. Our imaging observations of the shell show a slightly smaller radius at higher energies, consistent with Chandra results, and we find shrinkage as a function of increased energy along the jet direction, indicating that the electron outflow in the PWN may be simpler than that seen in other young PWNe. Combining NuSTAR with INTEGRAL, we find that the pulsar spectrum can be fit by a power law with Γ = 1.32 ± 0.07 up to 300 keV without evidence of curvature
Electronic structure of the ferromagnetic superconductor UCoGe from first principles
The superconductor UCoGe is analyzed with electronic structure calculations
using Linearized Augmented Plane Wave method based on Density Functional
Theory. Ferromagnetic and antiferromagnetic calculations with and without
correlations (via LDA+U) were done. In this compound the Fermi level is
situated in a region where the main contribution to DOS comes from the U-5f
orbital. The magnetic moment is mainly due to the Co-3d orbital with a small
contribution from the U-5f orbital. The possibility of fully non-collinear
magnetism in this compound seems to be ruled out. These results are compared
with the isostructural compound URhGe, in this case the magnetism comes mostly
from the U-5f orbital
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