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The Asymptotic Normalization Coefficient (ANC) method has proven to be useful in retrieving the direct part of the radiative capture cross section for a number of reactions of astrophysical interest. In this work, the study of the 26Si(p, γ)27P reaction, studied via the ANC in its extension for mirror nuclei will be discussed. [ABSTRACT FROM AUTHOR]

An experiment was performed by means of Trojan Horse Method (THM) at the LNS Tandem in Catania. The investigation of the relevant 19F(p,α)16O two-body reaction was performed by selecting the quasi free (QF) contribution of the 19F(²H,α16O)n three-body reaction, using the deuteron target as TH nucleus. The aim of this measurement is to obtain the 19F(p,α)16O cross section. The experimental set-up and the calibration of the detectors will be presented. [ABSTRACT FROM AUTHOR]

Owing the presence of the Coulomb barrier at astrophysically relevant kinetic energies, it is very difficult, or sometimes impossible to measure astrophysical reaction rates in laboratory. To overcome the problems related to the use of extrapolation procedure, the Trojan Horse Method (THM) has been applied extensively for the last 25 years to measure nuclear reaction cross sections of astrophysical interest. Although it has been mainly applied for charged particle-induced reactions, recently the THM has been found to have also a relevant role for neutron-induced ones. Here, the basic principle and a review of the main application of the Trojan Horse Method are presented, following a step-by-step description of the results concerning the study of the 17O(n,α)14C reaction. [ABSTRACT FROM AUTHOR]

The Trojan Horse Method (THM) has been applied extensively for the last 25 years to measure nuclear reaction cross sections of interest for astrophysics. Although it has been mainly applied for charged particle-induced reactions, recently it has been found to have also a relevant role for neutron-induced reactions. Here, some advantages of THM will be discussed and the preliminary results of the cosmological relevant 7Be(n,α)4He cross section measurement are discussed. [ABSTRACT FROM AUTHOR]

The 17O(p,α)14N reaction is of paramount importance for the nucleosynthesis in a number of stellar sites, including red giants (RG), asymptotic giant branch (AGB) stars, massive stars and classical novae. We report on the indirect study of the 17O(p,α)14N reaction via the Trojan Horse Method by applying the approach recently developed for extracting the resonance strength of the narrow resonance at Ec.m.R = 65 keV (EX =5.673 MeV). The strength of the 65 keV resonance in the 17O(p,α)14N reaction, measured by means of the THM, has been used to renormalize the corresponding resonance strength in the 17O + p radiative capture channel. [ABSTRACT FROM AUTHOR]

The role of oxygen in astrophysics is related to different problems as novae nucleosynthesis and gamma-ray astronomy. In particular, owing to the still present uncertainties on its rate, the 17O(p,α)14N is one of the most important reaction to be studied in order to get more information about the fate of oxygen in different astrophysical scenarios. [ABSTRACT FROM AUTHOR]

The abundance of 18F in Nova explosions is considered to be an important piece of information for the understanding of this astrophysical phenomenon. It is then necessary to study the nuclear processess that both produce and destroy this isotope in Novae. Among these latter reactions, the 18F(p,á)15O is one of the most important 18F destruction channels. Here we report on an experiment performed using the CRIB apparatus of the Center for Nuclear Study of the University of Tokyo. This was the first experiment that used the Trojan Horse method applied to a Radioactive Ion Beam induced reaction. [ABSTRACT FROM AUTHOR]

The abundance of 18F in Nova explosions is an important issue for the understanding of this astrophysical phenomenon. For this reason it is necessary to study the nuclear reactions that produce or destroy this isotope in novae. Among these latter processes, the 18F(p,α)15O is one of the main 18F destruction channels. We report here on the preliminary results of the first experiment that applies the Trojan Horse Method to a Radioactive Ion Beam induced reaction. The experiment was performed using the CRIB apparatus of the Center for Nuclear Study of The Tokyo University. [ABSTRACT FROM AUTHOR]

Nuclear clusters play a key role in the Trojan Horse Method for Nuclear Astrophysics studies. The Trojan Horse Method is an indirect technique to determine the astrophysical S(E) factor at ultra-low energies, free of Coulomb suppression and electron screening effect. Clustering makes it possible to use a few-body approach to derive a simple relationship between the measured 2 → 3 cross section and that of the 2 → 2 cross section of interest for astrophysics. The basic features of the Trojan Horse Method will be discussed and some recent results will be presented. [ABSTRACT FROM AUTHOR]

The 18O(p,α)15N reaction is of great importance in several astrophysical scenarios, as it influences the production of key isotopes such as 19F, 18O and 15N. In this work, a high accuracy 18O(p,α)15N reaction rate is proposed, based on the simultaneous fit of direct measurements and of the results of a new Trojan Horse experiment. In particular, we have focused on the study of the broad 660 keV 1/2+ resonance. Since Γ∼100-300 keV, it strongly influences the nearly-zero-energy region of the cross section by means of the low-energy tail of the resonant contribution and dominates the cross section at higher energies. Here we provide a factor of 2 larger reaction rate above T∼0.5 109 K based over our new improved determination of its resonance parameters. [ABSTRACT FROM AUTHOR]

In order to understand primordial and stellar nucleosynthesis, we have studied 2H(d,p)3H reaction at 0, 4 MeV down to astrophysical energies. Knowledge of this S-factor is interesting also to plan reactions for fusion reactors to produce energy. 2H(d,p)3H has been studied through the Trojan Horse Method applied to the three-body reaction 2H(3He,pt)H, at a beam energy of 17 MeV. Once protons and tritons are detected in coincidence and the quasi-free events are selected, the obtained S-factor has been compared with direct reactions results. Such data are in agreement with the direct ones, and a pole invariance test has been obtained comparing the present result with another 2H(d,p)3H THM one, performed with a different spectator particle (see fig. 1). [ABSTRACT FROM AUTHOR]

The Trojan Horse Method (THM) is an unique indirect technique allowing to measure astrophysical rearrangement reactions down to astrophysical relevant energies. The basic principle and a review of the recent applications of the Trojan Horse Method are presented. The applications aiming to the extraction of the bare astrophysical Sb(E) for some two-body processes are discussed. [ABSTRACT FROM AUTHOR]

The 17O(p,a)14N reaction is of paramount importance for the nucleosynthesis in a number of stellar sites, including red giants (RG), asymptotic giant branch (AGB) stars, massive stars and classical novae. We report on the indirect study of the 17O(p,a)14N reaction via the Trojan Horse Method by applying the approach recently developed for extracting the resonance strength of narrow resonance in the ultra-low energy region. [ABSTRACT FROM AUTHOR]

In this work the analysis of the 10B(23p, α)7Be and 11B(p, α)8Be reactions, studied via the indirect Trojan Horse Method (THM), is discussed. In the astrophysical context of light nuclei LiBeB depletion, the above mentioned reactions are the main responsible for the destruction of boron in the stellar interior. The THM application allows their investigation in the astrophysically relevant energy region, around the Gamow Peak (≈10 keV), overcoming the problems due to the presence of the Coulomb barrier and electron screening effect. The experimental procedure and the preliminary results are shown. [ABSTRACT FROM AUTHOR]

The 10B(p,α)7Be reaction is the main responsible for 10B destruction in stellar interior. In such environments the process takes places mainly through a resonant state of the compound 11C nucleus. The 10B(p,α)7Be reaction has been studied by means of the Trojan Horse Method using the 2H(10B,α7Be)n three-body reaction. The experiment was performed at the Laboratori Nazionali del Sud in Catania. The 10B(p,α)7Be reaction cross section has been extracted at low neutron momentum. [ABSTRACT FROM AUTHOR]