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Electronic state spectroscopy of C<sub>2</sub>Cl<sub>4</sub>
The VUV spectrum of C2Cl4 is reported in the energy range 3.8-10.8 eV (325-115 nm). Several photoabsorption features are observed for the first time, including a very weak low-lying band which is provisionally attributed to a π → π* triplet transition. Recent ab initio calculations of the molecule’s electronic transitions [Arulmozhiraja et al. J. Chem. Phys. 129 (2008) 174506] provide the basis for the present assignments below 8.5 eV. An extended ndπ series is proposed to account for several higher-energy Rydberg bands. The identification of vibrational structure, dominated by symmetric C=C and CCl2 stretching in excitations from the HOMO, largely agrees with previous spectroscopic studies. The present absolute photoabsorption cross sections cover a wider energy range than the previous measurements and are used to calculate UV photolysis lifetimes of this aeronomic molecule at altitudes between 20 and 50 km
Quantum memory for squeezed light
We produce a 600-ns pulse of 1.86-dB squeezed vacuum at 795 nm in an optical
parametric amplifier and store it in a rubidium vapor cell for 1 us using
electromagnetically induced transparency. The recovered pulse, analyzed using
time-domain homodyne tomography, exhibits up to 0.21+-0.04 dB of squeezing. We
identify the factors leading to the degradation of squeezing and investigate
the phase evolution of the atomic coherence during the storage interval.Comment: To appear in PRL. Changes to version 3: we present a larger data set
featuring somewhat less squeezing, but also better statistics and a lower
margin of error. Some additional revisions are made in response to the
referees' comment
Flares and variability from Sagittarius A*: five nights of simultaneous multi-wavelength observations
Aims. We report on simultaneous observations and modeling of mid-infrared
(MIR), near-infrared (NIR), and submillimeter (submm) emission of the source
Sgr A* associated with the supermassive black hole at the center of our Galaxy.
Our goal was to monitor the activity of Sgr A* at different wavelengths in
order to constrain the emitting processes and gain insight into the nature of
the close environment of Sgr A*. Methods. We used the MIR instrument VISIR in
the BURST imaging mode, the adaptive optics assisted NIR camera NACO, and the
sub-mm antenna APEX to monitor Sgr A* over several nights in July 2007.
Results. The observations reveal remarkable variability in the NIR and sub-mm
during the five nights of observation. No source was detected in the MIR, but
we derived the lowest upper limit for a flare at 8.59 microns (22.4 mJy with
A_8.59mu = 1.6+/- 0.5). This observational constraint makes us discard the
observed NIR emission as coming from a thermal component emitting at sub-mm
frequencies. Moreover, comparison of the sub-mm and NIR variability shows that
the highest NIR fluxes (flares) are coincident with the lowest sub-mm levels of
our five-night campaign involving three flares. We explain this behavior by a
loss of electrons to the system and/or by a decrease in the magnetic field, as
might conceivably occur in scenarios involving fast outflows and/or magnetic
reconnection.Comment: 10 pages, 7 figures, published in A&
The Anne Boleyn Illusion is a six-fingered salute to sensory remapping
The Anne Boleyn Illusion exploits the somatotopic representation of touch to create the illusion of an extra digit and demonstrates the instantaneous remapping of relative touch location into body-based coordinates through visuo-tactile integration. Performed successfully on thousands, it is also a simple demonstration of the flexibility of body representations for use at public events, in schools or in the home and can be implemented anywhere by anyone with a mirror and some degree of bimanual coordination
A computational approach for genome-wide mapping of splicing factor binding sites
A computational method is presented for genome-wide mapping of splicing factor binding sites that considers both the genomic environment and evolutionary conservation
Communications Biophysics
Contains reports on five research projects.United States Air Force (Contract AF19(604)-4112)National Institute of Neurological Diseases and Blindness (B369 Physiology
Quasilocality of joining/splitting strings from coherent states
Using the coherent state formalism we calculate matrix elements of the
one-loop non-planar dilatation operator of SYM between operators
dual to folded Frolov-Tseytlin strings and observe a curious scaling behavior.
We comment on the {\it qualitative} similarity of our matrix elements to the
interaction vertex of a string field theory. In addition, we present a solvable
toy model for string splitting and joining. The scaling behaviour of the matrix
elements suggests that the contribution to the genus one energy shift coming
from semi-classical string splitting and joining is small.Comment: 17 pages, 7 figures in 11 file
A new derivation of Luscher F-term and fluctuations around the giant magnon
15 pages, no figures; v2: added assumption on diagonal scattering and a section on generalizations; v3: minor changes, version accepted for publication in JHEPIn this paper we give a new derivation of the generalized Luscher F-term formula from a summation over quadratic fluctuations around a given soliton. The result is very general providing that S-matrix is diagonal and is valid for arbitrary dispersion relation. We then apply this formalism to compute the leading finite size corrections to the giant magnon dispersion relation coming from quantum fluctuations.Peer reviewe
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