14520037
Comments on higher derivative terms for the tachyon action
We consider the open string tachyon action in a world-sheet sigma model approach. We present explicit calculations up to order 8 in derivatives for the bosonic string, and mimic these to order 6 for the superstring, including terms with multiple derivatives acting on the tachyon field. We reproduce lower derivative terms obtained elsewhere, and speculate on the role of the world-sheet contact terms regularizing the action for the superstring tachyon.
210000411
Three form flux with N=2 supersymmetry on AdS(5) x S**5
120974809
Investigation of excited states in Mg-22 via resonant elastic scattering of Na-21+p and its astrophysical implications
The excited states in {sup 22}Mg have been investigated by the resonant elastic scattering of {sup 21}Na+p. A 4.0 MeV/nucleon {sup 21}Na beam was separated by the Center for Nuclear Study (CNS) radioactive ion beam separator (CRIB) and then used to bombard a thick (CH{sub 2}){sub n} target. The energy spectra of recoiled protons were measured at scattering angles of {theta}{sub c.m.}{approx_equal}172 deg.,146 deg., and 134 deg., respectively. A wide energy-range of excitation function in {sup 22}Mg (up to E{sub x}{approx}8.9 MeV) was obtained simultaneously with a thick-target method, and a state at 7.06 MeV was newly observed. The resonant parameters were deduced from an R-matrix analysis of the center-of-mass (c.m.) differential cross-section data with a SAMMY-M6-BETA code. The astrophysical resonant reaction rate for the {sup 18}Ne({alpha},p){sup 21}Na reaction was recalculated based on the present parameters. Generally speaking, the present rates are much smaller than the previous ones.