RPA (Rocket Propulsion Analysis) is a design tool for the performance prediction of the liquidpropellant rocket engines. RPA is written in Java and can be used under any operating system that has installed Java Runtime Environment (e.g. Mac OS ® X, Sun SolarisTM, MS WindowsTM, any Linux etc). The tool can be used either as a standalone GUI application or as an object-oriented library. This docu...

The properties of the low-lying, collective 2+1 states in neutron-rich oxygen isotopes are investigated in the framework of self-consistent microscopic models with effective Skyrme interactions. In RPA the excitation energies E 2 + 1 can be well described but the transition probabilities are much too small as compared to experiment. Pairing correlations are then accounted for by performing quas...

A fully consistent relativistic RPA calculation is performed for the monopole and dipole compression modes in nuclei. The emphasis is put on the effects of Dirac sea states which are generally neglected in relativistic RPA calculations. It is found that these effects can be quite important for the isoscalar monopole mode. The main contributions from the pairs of Fermi to Dirac sea states are th...

12-O-retinoylphorbol-13-acetate (RPA), an incomplete tumor promoter of the phorbol ester type and protein kinase C (PKC) activator, consists of two characteristic structural elements: the phorbol body and the retinoyl ester chain. Therefore, possible binding of the incomplete tumor promoter RPA to the human transport protein retinol-binding-protein (RBP) has been examined by molecular modeling ...

In a schematic model with equidistant fourfold degenerate single-nucleon levels, an isovector pairing force acting only on pairs with time-reversed orbits and spins, and a symmetry force, the RPA correlation energy rises almost linearly with the isospin T , thus producing a Wigner term in accordance with the empirical proportionality of the symmetry energy to T (T + 1). Nearly symmetric nuclei ...

It is well-known that the Random Phase Approximation (RPA) is equivalent to Time-Dependent Hartree-Fock (TDHF) to first order in the density fluctuations from the static Hartree-Fock ground state. Therefore either approach may be used to calculate giant resonance states in nuclei. Historically, the RPA approach has been more popular, particularly working directly in the response function formal...

Collective excitations in simple metal systems can be described successfully in terms of a local one-body excitation operator Q, due to the long range nature of the coulomb interaction. For the plasmon modes of a simple-metal slab, momentum expansions of Q are calculated using a variational procedure, equivalent to a restricted RPA calculation. The dispersion relation and the density fluctuatio...

A finite rank separable approximation for the quasiparticle RPA calculations with Skyrme interactions that was proposed in our previous work is extended to take into account the coupling between one-and two-phonon terms in the wave functions of excited states. It is shown that characteristics calculated within the suggested approach are in a good agreement with available experimental data.