4,171 research outputs found
Hyperfine structure of S-states in muonic deuterium
On the basis of quasipotential method in quantum electrodynamics we calculate
corrections of order and to hyperfine structure of S-wave
energy levels of muonic deuterium. Relativistic corrections, effects of vacuum
polarization in first, second and third orders of perturbation theory, nuclear
structure and recoil corrections are taken into account. The obtained numerical
values of hyperfine splitting meV (1S state) and
meV (2S state) represent reliable estimate for a
comparison with forthcoming experimental data of CREMA collaboration. The
hyperfine structure interval meV can be used for precision check of quantum
electrodynamics predictions for muonic deterium.Comment: 18 pages, 7 figure
X-radiation of the moon and Roentgen cosmic background according to data of AMS ''Luna-12''
Satellite measurements of lunar soft X radiation, and Roentgen cosmic backgroun
Radiative nonrecoil nuclear finite size corrections of order to the hyperfine splitting of S-states in muonic hydrogen
On the basis of quasipotential method in quantum electrodynamics we calculate
nuclear finite size radiative corrections of order to the
hyperfine structure of S-wave energy levels in muonic hydrogen and muonic
deuterium. For the construction of the particle interaction operator we employ
the projection operators on the particle bound states with definite spins. The
calculation is performed in the infrared safe Fried-Yennie gauge. Modern
experimental data on the electromagnetic form factors of the proton and
deuteron are used.Comment: 8 pages, 1 figur
The concept of correlated density and its application
The correlated density appears in many physical systems ranging from dense
interacting gases up to Fermi liquids which develop a coherent state at low
temperatures, the superconductivity. One consequence of the correlated density
is the Bernoulli potential in superconductors which compensates forces from
dielectric currents. This Bernoulli potential allows to access material
parameters. Though within the surface potential these contributions are largely
canceled, the bulk measurements with NMR can access this potential. Recent
experiments are explained and new ones suggested. The underlying quantum
statistical theory in nonequilibrium is the nonlocal kinetic theory developed
earlier.Comment: 14 pages, CMT30 proceeding
Natronoflexus pectinivorans gen. nov. sp. nov., an obligately anaerobic and alkaliphilic fermentative member of Bacteroidetes from soda lakes
Anaerobic enrichment with pectin at pH 10 and moderate salinity inoculated with sediments from soda lakes of the Kulunda Steppe (Altai, Russia) resulted in the isolation of a novel member of the Bacteroidetes, strain AP1T. The cells are long, flexible, Gram-negative rods forming pink carotenoids. The isolate is an obligate anaerobe, fermenting various carbohydrates to acetate and succinate. It can hydrolyze and utilize pectin, xylan, starch, laminarin and pullulan as growth substrates. Growth is possible in a pH range from 8 to 10.5, with an optimum at pH 9.5, and at a salinity range from 0.1 to 2 M Na+. Phylogenetic analysis based on 16S rRNA sequences placed the isolate into the phylum Bacteroidetes as a separate lineage within the family Marinilabilaceae. On the basis of distinct phenotype and phylogeny, the soda lake isolate AP1T is proposed to be assigned in a new genus and species Natronoflexus pectinivorans (=DSM24179T = UNIQEM U807T)
Soliton absorption spectroscopy
We analyze optical soliton propagation in the presence of weak absorption
lines with much narrower linewidths as compared to the soliton spectrum width
using the novel perturbation analysis technique based on an integral
representation in the spectral domain. The stable soliton acquires spectral
modulation that follows the associated index of refraction of the absorber. The
model can be applied to ordinary soliton propagation and to an absorber inside
a passively modelocked laser. In the latter case, a comparison with water vapor
absorption in a femtosecond Cr:ZnSe laser yields a very good agreement with
experiment. Compared to the conventional absorption measurement in a cell of
the same length, the signal is increased by an order of magnitude. The obtained
analytical expressions allow further improving of the sensitivity and
spectroscopic accuracy making the soliton absorption spectroscopy a promising
novel measurement technique.Comment: 9 pages, 7 figures
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