14723337
Functional equations for one-loop master integrals for heavy-quark production and Bhabha scattering
Abstract The method for obtaining functional equations, recently proposed by one of the authors [O.V. Tarasov, Phys. Lett. B 670 (2008) 67, arXiv:0809.3028 [hep-ph] ], is applied to one-loop box integrals needed in calculations of radiative corrections to heavy-quark production and Bhabha scattering. We present relationships between these integrals with different arguments and box integrals with all propagators being massless. It turns out that functional equations are rather useful for finding imaginary parts and performing analytic continuations of Feynman integrals. For the box master integral needed in Bhabha scattering, a new representation in terms of hypergeometric functions admitting one-fold integral representations is derived. The hypergeometric representation of a master integral for heavy-quark production follows from the functional equation.
118467843
Analytic result for the one-loop scalar pentagon integral with massless propagators
The method of dimensional recurrences proposed by Tarasov (1996, 2000) [1] ;  [2] is applied to the evaluation of the pentagon-type scalar integral with on-shell external legs and massless internal lines. For the first time, an analytic result valid for arbitrary space–time dimension d and five arbitrary kinematic variables is presented. An explicit expression in terms of the Appell hypergeometric function F3F3 and the Gauss hypergeometric function F12, both admitting one-fold integral representations, is given. In the case when one kinematic variable vanishes, the integral reduces to a combination of Gauss hypergeometric functions F12. For the case when one scalar invariant is large compared to the others, the asymptotic values of the integral in terms of Gauss hypergeometric functions F12 are presented in d=2−2ed=2−2e, 4−2e4−2e, and 6−2e6−2e dimensions. For multi-Regge kinematics, the asymptotic value of the integral in d=4−2ed=4−2e dimensions is given in terms of the Appell function F3F3 and the Gauss hypergeometric function F12.
119594766
New isotopeSi44and systematics of the production cross sections of the most neutron-rich nuclei
The results of measurements of the production of neutron-rich nuclei by the fragmentation of a {sup 48}Ca beam at 142 MeV/nucleon are presented. Evidence was found for the production of a new isotope that is the most neutron-rich silicon nuclide, {sup 44}Si, in a net neutron pickup process. A simple systematic framework was found to describe the production cross sections based on thermal evaporation from excited prefragments that allows extrapolation to other weak reaction products.
117190606
New isomer Alm32
120651816
The code LISE: A new version for "Windows"
Abstract The LISE code is intended to simulate medium-energy and high-energy fragment separators with electrostatic and/or magnetic selections. It is based on first-order optics and transport integral convolution techniques. Fragment separators such as LISE3, SISSI/LISE3 and SPEG at GANIL, FRS at GSI, COMBAS and ACCULINA at Dubna, A1200 and A1900 at NSCL, and RIPS at RIKEN are based on the separation of projectile-like fragments, and can be easily simulated via optical configuration files. The reaction mechanism assumed in this program is projectile fragmentation, suitable to simulate experiments at beam energies above 30  A  MeV. However, built-in tools such as the physical calculator, nucleus database utilities, relativistic reaction kinematics calculations and beam optics transport calculations make it a very useful tool below this energy limit as well. The program can therefore be used for forecasting and tuning experiments using heavy-ion beams with energies ranging from 10 keV up to a few GeV per nucleon.
41501572
Production cross sections from 82Se fragmentation as indications of shell effects in neutron-rich isotopes close to the drip-line
Production cross sections for neutron-rich nuclei from the fragmentation of a 82 Se beam at 139 MeV/u were measured. The longitudinal momentum distributions of 126 neutron-rich isotopes of elements 11 Z 32 were scanned using an experimental approach of varying the target thickness. Production cross sections with beryllium and tungsten targets were determined for a large number of nuclei including several isotopes first observed in this work. These are the most neutron-rich nuclides of the elements 22 Z 25 ( 64 Ti, 67 V, 69 Cr, and 72 Mn). One event was registered consistent with 70 Cr and another one with 75 Fe. The production cross sections are correlated with Qg systematics to reveal trends in the data. The results presented here confirm our previous results from a similar measurement using a 76 Ge beam and can be explained with a shell model that predicts a subshell closure at N = 34 around Z = 20. This is demonstrated by systematic trends and calculations with the abrasion-ablation model that are sensitive to separation energies.