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EMPIRE is a modular system of nuclear reaction codes, comprising various nuclear models, and designed for calculations over a broad range of energies and incident particles. The system can be used for theoretical investigations of nuclear reactions as well as for nuclear data evaluation work. Photons, nucleons, deuterons, tritons, helions ( 3 He), α's, and light or heavy ions can be selected as projectiles. The energy range starts just above the resonance region in the case of a neutron projectile, and extends up to few hundred MeV for heavy ion induced reactions. The code accounts for the major nuclear reaction models, such as optical model, Coupled Channels and DWBA (ECIS06 and OPTMAN), Multi-step Direct (ORION + TRISTAN), NVWY Multi-step Compound, exciton model (PCROSS), hybrid Monte Carlo simulation (DDHMS), and the full featured Hauser-Feshbach model including width fluctuations and the optical model for fission. Heavy ion fusion cross section can be calculated within the simplified coupled channels approach (CCFUS). A comprehensive library of input parameters based on the RIPL-3 library covers nuclear masses, optical model parameters, ground state deformations, discrete levels and decay schemes, level densities, fission barriers, and γ-ray strength functions. Effects of the dynamic deformation of a fast rotating nucleus can be taken into account in the calculations (BARFIT, MOMFIT).The results can be converted into the ENDF-6 format using the accompanying EM-PEND code. Modules of the ENDF Utility Codes and the ENDF Pre-Processing codes are applied for ENDF file verification. The package contains the full EXFOR library of experimental data in computational format C4 that are automatically retrieved during the calculations.EMPIRE contains the resonance module that retrieves data from the electronic version of the Atlas of Neutron Resonances by Mughabghab (not provided with the EMPIRE distribution), to produce resonance section and related covariances for the ENDF-6 formatted files. EMPIRE can be used to determine covariances of the calculated data using either sensitivity matrices along with the KALMAN code or employing Monte Carlo approach to produce model generated covariances. In both cases experimental data can be taken into account, either directly (KALMAN) or by feeding the EMPIRE calculated Monte Carlo modelling covariance as a prior to the least square fitting GANDR system. Publication quality graphs can be obtained using the powerful and flexible plotting package ZVView. Interactive plots with ZVView comparing experimental results with calculations can be produced with ENDVER modules.The backbone of the EMPIRE system are bash-shell UNIX scripts that provide for seamless console operation of EMPIRE on Linux, Mac OS X, and Microsoft Windows with GNU gfortran compiler installed. Additionally, the graphical interface, provides for an easy operation of the system on Linux, Mac OS X and virtual Linux machines running on Microsoft Windows. was implemented in the HMS-EMPIRE. This version also included combi...

Photon strength functions describing the average response of the nucleus to an electromagnetic probe are key input information in the theoretical modelling of nuclear reactions. Consequently they are important for a wide range of fields such as nuclear structure, nuclear astrophysics, medical isotope production, fission and fusion reactor technologies. They are also sources of information for widely used reaction libraries such as the IAEA Reference Input Parameter Library and evaluated data files such as EGAF.arXiv:1910.06966v1 [nucl-ex] 15 Oct 2019 Fig. 1 (Color online) Schematic representation on how NLDs and PSFs are extracted from the primary γ-ray spectrum. The firstgeneration γ-ray distribution (yellow triangle) is given by the product of the level density ρ(E i − E γ ) and the γ-ray transmission coefficient T γ (E γ ). All values of the elements of the ρ(E i − E γ ) and T γ (E γ ) vectors are allowed to vary in order to give the best fit to the P(E γ , E i ) landscape.

Damping of giant collective vibrations in nuclei is studied within the framework of the Landau-Vlasov kinetic equation. A phenomenological method of independent sources of dissipation is proposed for taking into account the contributions of one-body dissipation, the relaxation due to the two-body collisions and the particle emission. An expression for the intrinsic width of slow damped collective vibrations is obtained. In the general case, this expression cannot be represented as a sum of the widths associated with the different independent sources of the damping. This is a peculiarity of the collisional Landau-Vlasov equation where the Fermisurface distortion effect influences both the self-consistent mean field and the memory effect at the relaxation processes. The interplay between the one-body, the two-body, and the particle emission channels which contribute to the formation of the total intrinsic width of the isoscalar 2 ϩ and 3 Ϫ and isovector 1 Ϫ giant multipole resonances in cold and hot nuclei is discussed. We have shown that the criterion for the transition temperature T tr between the zero-sound and first-sound regimes in hot nuclei is different from the case of infinite nuclear matter due to the contribution from the one-body relaxation and the particle emission. In the case of the isovector GDR the corresponding transition can be reached at temperature T tr ϭ4 -5 MeV.

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