Search

We have performed the measurement of the 27Al(α, n) cross section at IFIN-HH for a range of energies from 2.5 to 5.2 MeV, using an array of 28 3He counters arranged in 3 concentric rings (ELIGANT-TN). Here we present the experimental setup and discuss the role of the 13C contamination which effects the measurements in the low-energy region. Energy-dispersive X-ray spectroscopy carried out before and after the experiment suggested an increase in the 13C concentration during the experiment.

The 19F(ρ,α)16O reaction is an important fluorine destruction chan- nel in the proton-rich outer layers of asymptotic giant branch (AGB) stars and it might also play a role in hydrogen-deficient post-AGB star nucleosynthesis. At present, theoretical models overproduce F abundances in AGB stars with re-spect to the observed values, thus calling for further investigation of the nuclear reaction rates involved in the production and destruction of fluorine. In the last years, new direct and indirect measurements improved significantly the knowl- edge of 19F(ρ,α)16O cross section at deeply sub-Coulomb energies (below 0.8 MeV). However, those data are larger by a factor of 1.4 with respect the previ- ous data reported in the NACRE compilation in the energy region 0.6-0.8 MeV. Using the Large High resolution Array of Silicons for Astrophysics (LHASA), we performed a new direct measurement of the 19F(ρ,α)16O. The goal of this experiment is to reduce the uncertainties in the nuclear reaction rate of the 19F(ρ,α)16O reaction. Here, experimental details, the calibration procedure and angular distributions are presented.

At the Extreme Light Infrastructure - Nuclear Physics facility (ELI-NP), high-power laser systems together with high-brilliance gamma beams are the main research tools. The status of the construction of the facility is reported. The emerging photofission experimental program with brilliant gamma beams at ELI-NP is presented with emphasis on the prepared day-one experiments. The physics cases of the flagship experiments at ELI-NP are discussed, as well as the related instruments which are under construction for their realization.

Position-sensitive silicon strip detectors represent one of the best solutions for the detection of charged particles as they provide good energy and position resolution over a large range of energies. A silicon array coupled with the gamma beams at the ELI-NP facility would allow measuring photodissociation reactions of interest for Big Bang Nucleosynthesis and on heavy nuclei intervening in the p-process. Forty X3 detectors for our ELISSA (ELI-NP Silicon Strip Detectors Array) project have been recently purchased and tested. We investigated several specifications, such as leakage currents, depletion voltage, and detector stability under vacuum. The energy and position resolution, and ballistic deficit were measured and analyzed. This paper presents the main results of our extensive testing. The measured energy resolution for the X3 detectors is better than results published for similar arrays (ANASEN or ORRUBA).

Present and future gamma-beam facilities represent a great opportunity to validate and evaluate the cross-sections of many photonuclear reactions at near-threshold energies. Monte Carlo (MC) simulations are very important to evaluate the reaction rates and to maximize the detection efficiency but, unfortunately, they can be very cputime-consuming and in some cases very hard to reproduce, especially when exploring near-threshold cross-section. We developed a software that makes use of the validated tracking GEANT4 libraries and the n-body event generator of ROOT in order to provide a fast, realiable and complete MC tool to be used for nuclear physics experiments. This tool is indeed intended to be used for photonuclear reactions at γ-beam facilities with ELISSA (ELI Silicon Strip Array), a new detector array under development at the Extreme Light Infrastructure - Nuclear Physics (ELI-NP). We discuss the results of MC simulations performed to evaluate the effects of the electromagnetic induced background, of the straggling due to the target thickness and of the resolution of the silicon detectors.

The Extreme Light Infrastructure (ELI) Pan-European initiative represents a major step forward in quest for extreme electromagnetic fields. The Extreme Light Infrastructure – Nuclear Physics (ELI-NP) laboratory is one of the three pillars of the ELI project, that aims to use such extreme electromagnetic fields for nuclear physics and quantum electrodynamics research. At ELI-NP two ten petawatt high-power laser systems together with a very brilliant narrow-width γ beam are the main research tools. Here the current status of the project and the experimental program related to nuclear research, which is under preparation at ELI-NP, are presented.