90 research outputs found
B ->PV Decays in the QCD Improved Factorization Approach
Motivated by recent CELO measurements and the progress of the theory of B
decays, we investigate decay modes in
the framework of QCD improved factorization. We find that all the measured
branching ratios are well accommodated in the reasonable parameter space and
predictions for the other decay modes are well below the experimental upper
limits. We also have calculated CP asymmetries in these decay modes.Comment: 24 pages, LaTex-2e, typos correcte
The Rotating Gliding Discharge in Quartz Tube and Open Half-Space at Atmospheric Pressure
Rotating sliding discharge (RGD) was investigated into limited volume and open half-space. The cur-rent-voltage characteristics of the discharge and its specifications are described. The results of optical research: photos and emission spectra of the discharge are presented
ПЕРЕВАГИ ВИКОРИСТАННЯ БІПОЛЯРНОГО ЕЛЕКТРОСКАЛЬПЕЛЯ В ХІРУРГІЇ МАГІСТРАЛЬНИХ СУДИН
Існуючі методи тимчасового припинення кровотечі в хірургії магістральних судин досить ефективні, проте, при деяких патологічних станах потрібне застосування новітніх методів гемостазу, що дозволяють зменшити травматичність маніпуляцій, забезпечують оптимальні умови для регенерації в інтраопераційній зоні. Проведені порівняльні дослідження свідчать про переваги біполярного електроскальпеля власної конструкції, що можливо використовувати в різних галузях хірургічної практики
Interaction of small size wave packet with hadron target
We calculate in QCD the cross section for the scattering of an energetic
small-size wave packet off a hadron target. We use our results to study the
small- behaviour of , the distribution over cross
section for the pion, in the leading -order.Comment: Revised version of the report CEBAF-TH-96-0
The dependence of the hard diffractive photoproduction of vector meson or photon and the range of pQCD validity
We consider two coupled problems.
We study the dependence on photon virtuality for the semihard
quasi--elastic photoproduction of neutral vector mesons on a quark, gluon or
real photon (at
GeV)). To this end we calculate the corresponding amplitudes (in an
analytical form) in the lowest nontrivial approximation of perturbative QCD. It
is shown that the amplitude for the production of light meson varies very
rapidly with the photon virtuality near .
We estimate the bound of the pQCD validity region for such processes. For the
real incident photon the obtained bound for the meson production is very
high. This bound decreases fast with the increase of , and we expect that
the virtual photoproduction at HERA gives opportunity to test the pQCD results.
The signature of this region is discussed. For the hard Compton effect the pQCD
should work good at not too high , and this effect seems measurable
at HERA.Comment: ReVTeX, 36 pages, 5 Postscript figures, uses epsf.st
Proceedings of the third French-Ukrainian workshop on the instrumentation developments for HEP
The reports collected in these proceedings have been presented in the third
French-Ukrainian workshop on the instrumentation developments for high-energy
physics held at LAL, Orsay on October 15-16. The workshop was conducted in the
scope of the IDEATE International Associated Laboratory (LIA). Joint
developments between French and Ukrainian laboratories and universities as well
as new proposals have been discussed. The main topics of the papers presented
in the Proceedings are developments for accelerator and beam monitoring,
detector developments, joint developments for large-scale high-energy and
astroparticle physics projects, medical applications.Comment: 3rd French-Ukrainian workshop on the instrumentation developments for
High Energy Physics, October 15-16, 2015, LAL, Orsay, France, 94 page
Search for double beta decay processes in 106Cd with the help of 106CdWO4 crystal scintillator
A search for the double beta processes in 106Cd was carried out at the Gran
Sasso National Laboratories of the INFN (Italy) with the help of a 106CdWO4
crystal scintillator (215 g) enriched in 106Cd up to 66%. After 6590 h of data
taking, new improved half-life limits on the double beta processes in 106Cd
were established at the level of 10^{19}-10^{21} yr; in particular,
T_{1/2}(2\nu \epsilon \beta^+) > 2.1 10^{20} yr, T_{1/2}(2\nu 2\beta^+) > 4.3
10^{20} yr, and T_{1/2}(0\nu 2\epsilon) > 1.0 10^{21} yr. The resonant
neutrinoless double electron captures to the 2718 keV, 2741 keV and 2748 keV
excited states of 106Pd are restricted to T_{1/2}(0\nu 2K) > 4.3 10^{20} yr,
T_{1/2}(0\nu KL1) > 9.5 10^{20} yr and T_{1/2}(0\nu KL3) > 4.3 10^{20} yr,
respectively (all limits at 90% C.L.). A possible resonant enhancement of the
0\nu 2\epsilon processes is estimated in the framework of the QRPA approach.
The radioactive contamination of the 106CdWO4 crystal scintillator is reported.Comment: Minor changes of half-life limits after improving the data analysis;
version accepted for publication on Phys. Rev.
Distribution of valence quarks and light-cone QCD sum rules
A method for calculating the pion structure function directly in terms of
light-cone wave functions is suggested. Taking twist-2 and twist-4 pion
light-cone wave functions into account, it is shown that the QCD sum rule
prediction is in agreement with quark distribution obtained from analysis of
the Drell-Yan process. Twist-4 quark-gluon light-cone wave functions give a
large positive contribution to the pion structure function for x_B<0.2. A new
constraint on the twist-2 pion light-cone wave function is obtained. We argue
that the leading twist pion wave function \phi_\pi(u) \simeq 1 for u=0.3 with
an accuracy of about 20-30%.Comment: 18 pages, Latex, epsfig, 2 figure
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