Hello, A change in allocation has been requested: Requester: wiringa (Robert Wiringa) Project: qmc_for_nuclei Title: Quantum Monte Carlo Calculations of Light Nuclei Description: A) Electroweak moments and transitions We are studying a variety of electroweak properties and transitions in light p-shell nuclei, including both one- and two-body charge and current operators that include the effect of meson-exchange currents. We are nearing completion of work on magnetic moment and M1 transitions in A=7-9 nuclei. We will extend these calculations to moments and M1 and M3 transitions in A=10 nuclei in FY13. We have also been studying E0 and E2 transitions in A=10 in co-operation with an experimental program at ATLAS, and finding they may provide new constraints on three-nucleon forces. We are just now starting work on longitudinal and transverse response functions, which have not previously been studied for A>7 nuclei. We expect to use 160,000 hours for this work in FY13. B) A=11,12 nuclei Extensive effort has gone into GFMC calculations of 12C using the BlueGene/P system, but only a few exploratory calculations of other A>10 nuclei have been made. We want to explore different possible trial functions for other cases like 11Li, 11B, and 12Be, particularly wave functions that are "clusterized." The VMC codes for these trial functions were made more efficient for large nuclei this year by adding OpenMP commands in addition to the existing MPI structure. We are also continuing studies of unnatural parity and intruder states in A=10 nuclei, where one or two nucleons are promoted from the p-shell to the sd-shell. A particularly interesting case is that of 1- states in 10B which exhibit significant isospin-mixing. We would like 80,000 cpu hours to this work in FY13 C) Asymptotic normalization coefficients and resonance widths for alpha-decay In the last two years we have developed a new method for evaluating asymptotic normalization coefficients (ANCs) that characterize the long-range tails of nuclear bound states and are the key determinant in low-energy astrophysics reaction rates. The calculation uses a short-range integral technique that can make do with relatively simple variational wave functions. A variant of this method allows the calculation of widths of narrow unbound states. The method has been applied to single-nucleon emission up to A=9 nuclei. In FY13 we plan to adapt the method for alpha-particle emission and study ANCs and widths nuclei up to A=10. We will need 40,000 hours for this work in FY13. D) Nucleon-nucleus scattering We are continuing our studies of nucleon-nucleus scattering for n+3H, p+3He, n+4He, and p+4He, and for parity-violating (PV) n+4He scattering. Our earlier n+4He studies were limited to scattering energies of 4 MeV or less. We have made some progress this year in developing better trial wave functions that can be used up to 20 MeV. We would also like to move to some heavier systems like n+8He scattering. We would like 40,000 cpu hours available for this work. Current: undetermined amount Justification: Requested: 75000 A specific reason has been given: Our present calculations are not as rapidly convergent as expected so we have already used 80k+ hours of the 140k allocated for the first 6 months of FY13. We would like an additional 25k/quarter for the remainder of FY13 above our previous award. This needs to be approved and the final allocation amount decided upon. Thank You, The LCRC Accounts System