10Be i molekulska stanja

The 10Be excitation energy spectra have been obtained from the inclusive and coincident measurements of the reactions: 7Li +7Li at E0 = 8 and 30 MeV and 9Be +7Li at E0 = 52 MeV. Contributions of the 10Be states below 12 MeV in excitation have been observed. Decays of the states at 9.6, 10.2 and 11.8 into a +6He and, for the first time, into a +6He* have been found. The results are discussed in addition to the other experimental data and recent theoretical predictions. Proposals for future measurements to search for exotic structures in carbon nuclei are also made.Proučavamo ekscitacijske energijske spektre 10Be iz inkluzivnih i koincidentnih mjerenja reakcija 7Li +7Li na E0 = 8 i 30 MeV, te 9Be +7Li na E0 = 52 MeV. Opaženi su doprinosi stanja 10Be u energiji uzbude do 12 MeV. Nađeni su raspadi stanja na 9.6, 10.2 i 11.8 MeV na α +6He te, po prvi put, na α +6He∗. Ovi se rezultati razmatraju zajedno s ostalim eksperimentalnim podacima i novijim teorijskim predviđanjima. Predlažu se buduća mjerenja u kojima bi se tražila stanja lakih jezgara egzotične građe

10Be i molekulska stanja

The 10Be excitation energy spectra have been obtained from the inclusive and coincident measurements of the reactions: 7Li +7Li at E0 = 8 and 30 MeV and 9Be +7Li at E0 = 52 MeV. Contributions of the 10Be states below 12 MeV in excitation have been observed. Decays of the states at 9.6, 10.2 and 11.8 into a +6He and, for the first time, into a +6He* have been found. The results are discussed in addition to the other experimental data and recent theoretical predictions. Proposals for future measurements to search for exotic structures in carbon nuclei are also made.Proučavamo ekscitacijske energijske spektre 10Be iz inkluzivnih i koincidentnih mjerenja reakcija 7Li +7Li na E0 = 8 i 30 MeV, te 9Be +7Li na E0 = 52 MeV. Opaženi su doprinosi stanja 10Be u energiji uzbude do 12 MeV. Nađeni su raspadi stanja na 9.6, 10.2 i 11.8 MeV na α +6He te, po prvi put, na α +6He∗. Ovi se rezultati razmatraju zajedno s ostalim eksperimentalnim podacima i novijim teorijskim predviđanjima. Predlažu se buduća mjerenja u kojima bi se tražila stanja lakih jezgara egzotične građe

Eksperimentalni dokazi (pokazatelji) molekulske strukture lakih jezgri

Experimental studies of the cluster structures in 9,10Be and 13,14C have been performed. Evidence for the α+5He decay of 9Be excited states, α+6He decays of 10Be∗ , α+9Be decay of 13C ∗ and for the decays of 14C ∗ into α+10Be were found. These decay processes indicate the cluster structures of the excited states. The results are compared with recent suggestions for the presence of molecule-like structures based upon α-particles and valence neutrons in Be and C isotopes.Eksperimentalno smo proučavali nakupinske strukture u 9,10Be i 13,14C. Našli smo α+5He raspad uzbuđenog stanja 9Be, α+6He raspad 10Be∗ , α+9Be raspad 13C ∗ te raspad 14C ∗ u α+10Be. Ovi procesi ukazuju na nakupinske strukture uzbuđenih stanja tih jezgri. Ishode mjerenja uspoređujemo s novim objašnjenjima o prisutnosti molekulama-sličnih struktura zasnovanim na α-česticama i valentnim neutronima u izotopima Be i C

Eksperimentalni dokazi (pokazatelji) molekulske strukture lakih jezgri

Experimental studies of the cluster structures in 9,10Be and 13,14C have been performed. Evidence for the α+5He decay of 9Be excited states, α+6He decays of 10Be∗ , α+9Be decay of 13C ∗ and for the decays of 14C ∗ into α+10Be were found. These decay processes indicate the cluster structures of the excited states. The results are compared with recent suggestions for the presence of molecule-like structures based upon α-particles and valence neutrons in Be and C isotopes.Eksperimentalno smo proučavali nakupinske strukture u 9,10Be i 13,14C. Našli smo α+5He raspad uzbuđenog stanja 9Be, α+6He raspad 10Be∗ , α+9Be raspad 13C ∗ te raspad 14C ∗ u α+10Be. Ovi procesi ukazuju na nakupinske strukture uzbuđenih stanja tih jezgri. Ishode mjerenja uspoređujemo s novim objašnjenjima o prisutnosti molekulama-sličnih struktura zasnovanim na α-česticama i valentnim neutronima u izotopima Be i C

Structure of 24Mg excited states and their influence on nucleosynthesis

The main idea of the two presented experiments is to study the decay of resonances in 24Mg at excitation energies above the 12C+12C decay thresh- old, in the astrophysical energy region of interest. The measurement of the 12C(16O,α)24Mg* reaction was performed at INFN-LNS in Catania. Only the α+20Ne decay channel of 24Mg is presented here, because it was a motivation for conducting a new experiment, a study of the 4He(20Ne,4He)20Ne reaction, performed at INFN-LNL in Legnaro. Some preliminary results of this measurement are also presented

Detection of hidden explosives in different scenarios with the use of nuclear probes

Abstract The detection of landmines by using available technologies is a time consuming, expensive and extremely dangerous job, so that there is a need for a technological breakthrough in this field. Atomic and nuclear physics based sensors might offer new possibilities in de-mining. Technology and methods derived from the studies applied to the detection of landmines can be successfully applied to the screening of cargo in customs inspections

Quasifree mechanism in the Li-6 + Li-6 → 3α reaction at low energy

The Li-6 + Li-6 → 3α reaction was measured in a kinematically complete experiment at 3.1 and 2.5 MeV to investigate the presence of quasifree processes at sub-Coulomb energies. Results from the present experiment show a very clear evidence of quasifree mechanisms with an alpha-particle spectator either in the target or in the projectile. To check the occurrence of quasifree processes, "energy sharing" and "angular correlation" analyses have been performed in the framework of the plane wave impulse approximation, both leading to consistent results. The huge peak in the angular correlation spectra, previously ascribed to the "anomalous quasifree" process, corresponds instead to the population of the 22.2-MeV (2(+), Γ = 800 keV) state of Be-8

12C states populated in 10B+10B reactions

10B+10B reactions are measured with 50 and 72 MeV beams. The large spin of both beam and target nuclei (Jπ=3+) is particularly suitable for the population of high spin states in the exit channels. Population and decay of different states in 12C are studied through sequential decay reactions. The 12C excitation energy spectrum obtained from the 10B(10B, 8Be) reaction shows a number of both known and new states. In particular, a new state at Ex=24.4MeV is observed to be strongly populated in the triple α-particle coincidences. The rarely seen state at Ex=30.3MeV is found to be strong in the d+10B decay channel, reinforcing the previous suggestions that it has the exotic 2α+2d molecular structure