Why going underground g-background Gran Sasso shielding: 3800 m w.e. 40K E>3.5MeV Counts/keV/hours 0.33 0.00024 214Bi 232Th cosmic rays Environmental radioactivity Therefore, the advantage of an underground environment is evident for high Q-value reactions such as 14N(p,)15O, 15N(p,)16O, 17O(p,)18F, 25Mg(p,)26Al...... Radiation LNGS/out muons neutrons 10-6 10-3

Why going underground n-background Therefore, the advantage of an underground environment is evident for n-source reaction as 13C(a,n)16O, 22Ne(a,n)25Mg Radiation LNGS/out muons neutrons 10-6 10-3

Underground Pb-shielding and Radon box HPGe fully sorrounded (55°) with 15 cm of Pb

25Mg(p,)26Al - HPGe spectra ER = 190 keV

LUNA –> 1991-2017 LNGS Lab LUNA I 50 kV LUNA II 400 kV Voltage Range : 1 - 50 kV Output Current: 1 mA Beam energy spread: 20 eV LNGS Lab LUNA I 50 kV Voltage Range : 50 - 400 kV Output Current: 500 mA Beam energy spread: 70 eV LUNA II 400 kV

p(d,g)3He, d(a,g)6Li, 3He(3He, 2p)4He, 3He(a,g)7Be14N(p,g)15O LUNA -> 1991-2017 BBN and H-burning in the Sun and solar neutrinos: p(d,g)3He, d(a,g)6Li, 3He(3He, 2p)4He, 3He(a,g)7Be14N(p,g)15O Age of Globular Clusters and C production in AGB: 14N(p,g)15O AGB nucleosynthesis – light nuclei abundances: 14N(p,g)15O, 15N(p,g)16O, 17O(p,g)18F, 17O(p,a)14N, 18O(p,g)19F, 18O(p,a)15N, 22Ne(p,g)23Na, 23Na(p,g)24Mg, 25Mg(p,g)26Al

LUNA MV – future setup LNGS Lab LUNA-MV 2019 3.5 MV

Layout of the new LUNA-MV facility Thanks to MIUR by 2 «progetti premiale» total grant: 5.3 M€ 5.5 m 27 m 12.5 m NPA VIII, LNS-Catania

The accelerator and the neutron shielding 1H+ (TV: 0.3 – 0.5 MV): 500 μA inline Cockcroft Walton accelerator TERMINAL VOLTAGE: 0.2 – 3.5 MV Precision of terminal voltage reading: 350 V Beam energy reproducibility: 0.01% TV Beam energy stability: 0.001% TV / h Beam current stability: < 5% / h 1H+ (TV: 0.5 – 3.5 MV): 1000 μA 4He+ (TV: 0.3 – 0.5 MV): 300 μA He 4He+ (TV: 0.5 – 3.5 MV): 500 μA 12C+ (TV: 0.3 – 0.5 MV): 100 μA C 12C+ (TV: 0.5 – 3.5 MV): 150 μA 12C++ (TV: 0.5 – 3.5 MV): 100 μA 80 cm thick concrete shielding calculated by GEANT4 & MCNP En = 5.6 MeV, 2 103 n/s, isotropic DA COMPATTARE CON LA PRECEDENTE MCNP: Fn = 1.38 10-7 n/(cm2 s) GEANT4: Fn = 3.40 10-7 n/(cm2 s) Fn(LNGS) = 3 10-6 n/(cm2 s) NPA VIII, LNS-Catania

LUNA future measurements Main neutron sources: 13C(a,n)16O, 22Ne(a,n)25Mg Explovive CNO burning: 15O(a,g)19Ne, 14O(a,g)18Ne, 18Ne(a,p)21Na He and advaced burnings: 12C(a,g)16O, 12C(12C, p)23Na, 12C(12C,a)20Ne, 16O(a,g)20Ne

LUNA-MV basic schedule Action Date Approval of the first HVEE technical design October 2016 Opening of the tendering procedure for LUNA-MV plants November 2016 Submission of the Authorization request to «Prefettura dell’Aquila» December 2016 Beginning of the clearing works in Hall B February 2017 End of the tendering procedure for the new LUNA-MV building June 2017 Beginning of the construction works in Hall B September 2017 End of the tendering procedure for LUNA-MV plants October 2017 Beginning of the construction of the plants in the LUNA-MV building December 2017 Completion of the new LUNA-MV building and plants April 2018 In-house acceptance test for the new LUNA-MV accelerator May 2018 LUNA-MV accelerator delivering at LNGS July 2018 Conclusion of the commissioning phase December 2018 Beginning First Experiment January 2019

LUNA MV- scientific program (2018  2022) Commissioning measurement: 14N(p,g)15O. High scientific interest for revised data covering a wide energy range (400 keV- 3.5 MeV). Scientific results of high impact but reduced risk immediately after commissioning phase 12C+12C: solid state target. Gamma and particle detectors 13C(a,n)16O: enriched 13C solid or gas target. Neutron detector 22Ne(a,n)25Mg: enriched 22Ne gas target. Neutron detector. Next steps (not before 2023…): 12C(a,g)16O: 12C solid target depleted in 13C and alpha beam or a jet gas target and 12C beam.

Stellar environments for s-process WEAK : Massive stars 22Ne(a,n)25Mg T> 109 K nn=106-1011 cm-3 MAIN : low mass AGB (1-3 M⊙) 13C(a,n)16O (dominant) T= 80 - 150  106 K nn=106-107 cm-3 22Ne(a,n)25Mg (marginal) T= 250 - 400  106 K nn=109-1010 cm-3

Experimental Results – 13C(a,n)16O

Experimental Results – 13C(a,n)16O some conclusion: - low energy data points do not constrain the fit with respect to the subthreshold resonance - quoted uncertainties are large  probably also a mixture of systematic and statistical uncertainties, e.g. in Drotleff scattering of data is unexpectely small with respect to error bars - most data point below E = 350 keV are higher than the fit curves, i.e. Heil R-matrix curve  indication for beam induced background?

Carbon burning in stars

12C+12C - Total S-factor

Carbon burning in stars

Experimental results in g-ray spectrometry Underground laboratory is the best place to get lower energy

Underground Pb-shielding and Radon box HPGe fully sorrounded (55°) with 15 cm of Pb

Long-Term Developments LUNA-MV JUNA/CJPL CASPAR New underground facilities will open up exiting new opportunities for further major breakthrough in the field

The LUNA COLLABORATION (as of May 2017) G.F. Ciani*, L. Csedreki, L. Di Paolo, A. Formicola, I. Kochanek, M. Junker, - INFN LNGS /*GSSI, Italy D. Bemmerer, K. Stoeckel, M. Takacs, - HZDR Dresden, Germany C. Broggini, A. Caciolli, R. Depalo, R. Menegazzo, D. Piatti - Università di Padova and INFN Padova, Italy C. Gustavino - INFN Roma1, Italy Z. Elekes, Zs. Fülöp, Gy. Gyurky, T. Szucs -MTA-ATOMKI Debrecen, Hungary O. Straniero -INAF Osservatorio Astronomico di Collurania, Teramo, Italy F. Cavanna, P. Corvisiero, F. Ferraro, P. Prati, S. Zavatarelli -Università di Genova and INFN Genova, Italy A. Guglielmetti, -Università di Milano and INFN Milano, Italy A. Best, A. Di Leva, G. Imbriani, - Università di Napoli and INFN Napoli, Italy G. Gervino - Università di Torino and INFN -Torino, Italy M. Aliotta, C. Bruno, T. Chillery, T. Davinson - University of Edinburgh, United Kingdom G. D’Erasmo, E.M. Fiore, V. Mossa, F. Pantaleo, V. Paticchio, R. Perrino, L. Schiavulli, A. Valentini- Università di Bari and INFN Bari, Italy NPA VIII, LNS-Catania