LUNA: Status and Prospects

Abstract

The essential ingredients of nuclear astrophysics are the thermonuclear reactions which shape the life and death of stars and which are responsible for the synthesis of the chemical elements in the Universe. Deep underground in the Gran Sasso Laboratory the cross sections of the key reactions responsible for the hydrogen burning in stars have been measured with two accelerators of 50 and 400 kV voltage right down to the energies of astrophysical interest. As a matter of fact, the main advantage of the underground laboratory is the reduction of the background. Such a reduction has allowed, for the first time, to measure relevant cross sections at the Gamow energy. The qualifying features of underground nuclear astrophysics are exhaustively reviewed before discussing the current LUNA program which is mainly devoted to the study of the Big-Bang nucleosynthesis and of the synthesis of the light elements in AGB stars and classical novae. The main results obtained during the study of reactions relevant to the Sun are also reviewed and their influence on our understanding of the properties of the neutrino, of the Sun and of the Universe itself is discussed. Finally, the future of LUNA during the next decade is outlined. It will be mainly focused on the study of the nuclear burning stages after hydrogen burning: helium and carbon burning. All this will be accomplished thanks to a new 3.5 MV accelerator able to deliver high current beams of proton, helium and carbon which will start running under Gran Sasso in 2019. In particular, we will discuss the first phase of the scientific case of the 3.5 MV accelerator focused on the study of ${}^{12}$C+${}^{12}$C and of the two reactions which generate free neutrons inside stars: ${}^{13}$C($\alpha$,n)${}^{16}$O and ${}^{22}$Ne($\alpha$,n)${}^{25}$Mg.

To be published in Progress in Particle and Nuclear Physics 98C (2018) pp. 55-84

References in corpus (35)

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• The effects of He I 10830 on helium abundance determinations
• Study of the 12C+12C fusion reactions near the Gamow energy
• Activation measurement of the 3He(alpha,gamma)7Be cross section at low energy
• Rubidium-Rich Asymptotic Giant Branch Stars
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• First measurement of the 14N(p,gamma)15O cross section down to 70 keV
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• 3He(alpha,gamma)7Be cross section at low energies
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• Precision study of ground state capture in the 14N(p,gamma)15O reaction
• The 3He(alpha,gamma)7Be S-factor at solar energies: the prompt gamma experiment at LUNA
• Improved Direct Measurement of the 64.5 keV Resonance Strength in the 17O(p,a)14N Reaction at LUNA
• Ultra-sensitive in-beam gamma-ray spectroscopy for nuclear astrophysics at LUNA
• High-energy break-up of 6Li as a tool to study the Big-Bang nucleosynthesis reaction 2H(alpha,gamma)6Li
• New determination of the 13C(a, n)16O reaction rate and its influence on the s-process nucleosynthesis in AGB stars
• Activation measurement of the 3He(a,g)7Be reaction cross section at high energies
• First Direct Measurement of the ^{17}O(p,γ)^{18}F Reaction Cross-Section at Gamow Energies for Classical Novae
• Direct measurement of low-energy ${}^{22}$Ne(p,$\gamma$)${}^{23}$Na resonances
• The 14N(p,gamma)15O reaction studied with a composite germanium detector
• Preparation and characterisation of isotopically enriched Ta${}_2$O${}_5$ targets for nuclear astrophysics studies
• ${}^{22}$Ne and ${}^{23}$Na ejecta from intermediate-mass stars: The impact of the new LUNA rate for ${}^{22}$Ne(p,$\gamma$)${}^{23}$Na
• Direct measurement of the 15N(p,gamma)16O total cross section at novae energies
• Probing nuclear rates with Planck and BICEP2
• An actively vetoed Clover gamma-detector for nuclear astrophysics at LUNA
• Constraining the S factor of 15N(p,g)16O at Astrophysical Energies
• Concurrent application of ANC and THM to assess the ${}^{13}\mathrm{C}(\alpha ,n{)}^{16}\mathrm{O}$ absolute cross section at astrophysical energies and possible consequences for neutron production in low-mass AGB stars
• New $\alpha$ ANC measurement of the 1/2${}^{+}$ state in ${}^{17}$O at 6.356 MeV, that dominates the ${}^{13}$C($\alpha$,n)${}^{16}$O reaction rate at temperatures relevant for the s-process
• Neutron-induced background by an alpha-beam incident on a deuterium gas target and its implications for the study of the 2H(alpha,gamma)6Li reaction at LUNA
• The impact of the revised ${}^{17}$O$(p,\alpha {)}^{14}$N reaction rate on ${}^{17}$O stellar abundances and yields
• Constraining Big Bang lithium production with recent solar neutrino data
• Cosmic-ray induced background intercomparison with actively shielded HPGe detectors at underground locations

Cited by in corpus (4)

• A new approach to monitor 13C-targets degradation in situ for 13C(alpha,n)16O cross-section measurements at LUNA
• The muon intensity in the Felsenkeller shallow underground laboratory
• Big Bang Nucleosynthesis and Neutrino Cosmology
• Experimental nuclear astrophysics in Italy