Stato dellesperimento LUNA e del progetto LUNA MV

Stato dell’esperimento LUNA e del progetto LUNA MV- Cd. S MI giugno 2015 Alessandra Guglielmetti Università degli Studi di Milano e INFN, Milano, ITALY Laboratory Underground Nuclear Astrophysics § L’esperimento LUNA: misure recenti e programmi futuri § Stato del Progetto Premiale LUNA MV Alessandra Guglielmetti & Davide Trezzi (assegnista UNIMI)

Recent activities at LUNA 400 k. V: 17 O(p, a)14 N and 18 O(p, a)15 N reactions • In AGB stars ( T=0. 03 -0. 1 GK ) CNO cycle takes place in H burning shell • Measured 17 O/16 O and 18 O/16 O abundances in pre-solar grain give information on AGB surface composition • Information on mixing processes if cross sections are well known

17 O(p, a)14 N and 18 O(p, a)15 N 17 O(p, a)14 N Q = 1. 2 Me. V Two narrow resonances at 70 and 193 ke. V Main goal: 70 ke. V resonance reactions Q = 4 Me. V Two narrow resonances at 95 and 152 ke. V Main goals: • rescan excitation function • 95 ke. V resonance (strength and energy) • Measure below 70 ke. V

17 O(p, a)14 N and 18 O(p, a)15 N SILICON DETECTOR reactions proton beam from LUNA 400 k. V enriched targets 17 O or 18 O 8 silicon detectors SOLID TARGET POSITION foils of Al Mylar to stop backscattered protons low alpha particle energy (200250 ke. V for 17 O(p, a)14 N reaction)

The 17 O(p, a)14 N Blackmon 95 Resonance strength (ne. V) 14 12 10 8 6 reaction: 70 ke. V res Sergi 10 LUNA 14 PR EL IM IN AR Y 4 2 0 • Very preliminary analysis favours a larger strength value compared with literature • If confirmed, it would have an astrophysical impact

The 18 O(p, a)15 N reaction Data taking completed. Data analysis on going 152 ke. V resonance PRELIMINARY 334 ke. V resonance 216 ke. V resonance In agreement with previous data Might improve precision on resonance energy and strength 95 ke. V resonance strength: precision about 10% (20 -30% literature) energy determined with 0. 5 ke. V precision (2. 2 ke. V literature) 60 ke. V measured with about 20% statistical uncertainty

Recent activities at LUNA 400 k. V: 22 Ne(p, g)23 Na reaction Ne. Na cycle of H burning. Active in astrophysical novae Impact on the abundances of: 22 Ne (factor 100) 23 Na (factor 7) 24 Mg (factor 70)

The 22 Ne(p, g)23 Na reaction The “red” resonances have been directly observed for the first time For the resonances at 71, 105 and 215 ke. V in “black” an upper limit has been found 2 oom or more lower with respect to previous direct measurements On going BGO phase (71 and 105 res. plus DC from 200 to 360 ke. V)

(p, 25 Mg 22 Na (p, 26 Al (p (p, 24 Mg (p, e+ 6 s e+ 7 s (p, 23 Na , 27 Si 26 Mg 25 Al 22 Ne (p, 20 Ne e+ 3 yr 21 Na (p, e+ 19 F 21 Ne 22 s Ne. Na Cycle Now “on beam”: the 23 Na(p, g)24 Mg and 18 O(p, g)19 F reactions - AGB nucleosynthesis (p, 4 s + e 27 Al Mg. Al Cycle 23 Na(p, g) 19 F 24 Goal of of 18 O(p, g) measurement: Mg measurement: 95 ke. V 144 resonance ke. V resonance and DC component. BGO detector first, HPGe if feasible BGO detector first. HPGe if feasible

LUNA 400 k. V new program 2016 -2019: a bridge toward LUNA MV 13 C(a, n)16 O – neutron source (LUNA MV) 12 C(p, g)13 N and 13 C(p, g)14 N – relative abundance of 12 C-13 C in the deepest layers of H-rich envelopes of any star 2 H(p, g)3 He – 2 H production in BBN (feasibility test already performed) 22 Ne(a, g)26 Mg (LUNA MV) 6 Li(p, g)7 Be – competes with 22 Ne(a, n)25 Mg neutron source – improves the knowledge of 3 He(a, g)7 Be key reaction of p-p chain (LUNA MV)

LUNA MV project Dimensions of the hall: 27 x 11 x 5 m 3 OPERA decommissioning started in Jan 2015. Removed 45000 bricks out of 130000, electronics, cooling system and some mechanical parts. Should be finished by October 2016 (S. Gazzana link to LUNA MV)

LUNA MV project Accelerator: Intense H+, 4 He+, 12 C+ e 12 C++ beams in the energy range: 350 ke. V-3. 5 Me. V. One beam line with all necessary elements (magnets, pumps, valves, . . . ). Total budget about 3. 9 Meuro: from LUNA MV Premium projects (total 5. 3 Meuro) Tendering procedure: full documentation submitted to INFN central administration at end of february 2015. On March 18 th the INFN executive board approved the tendering. Tender published on April 24 th on European official gazette. Two factories are qualified have been officially invited to produce an offer before September 2015. Tender assignment: 50% tecnical performances (beam intensity, beam quality, maintenance, additional components, …) , 50% price RUP: G. Imbriani, Università di Napoli DEC & designer: M. Junker, LNGS

LUNA MV project Building & shielding: GEANT 4 simulations with different materials are under development in order to find out the best compromise among performance as neutron shield, price, easiness of decommissioning, thickness (maximize internal space, … ) Contacts with Jlab: new materials for n shielding (LWPC, B 4 C concrete) Possibility of multi layer configurations. Use HDPe granulate available at LNGS?

LUNA MV project - timeline Accelerator: Contract signed by 12/2015. Accelerator built and tested by the producing company by 11/2017. Accelerator delivered to LNGS by 01/2018 Accelerator installed and tested at LNGS by 07/2018. Then first experiments Building & shielding: Final solution for shielding to be defined by 06/2015. Engineering of shielding concluded by 01/2016. Engineering of building (standard metal structure) concluded by 06/2016 Plants: Risk analysis concluded by 02/2016. Engineering of plants concluded by 06/2016. Details of plants are necessary to proceed with authorization for the accelerator (to be submitted by 06/2016)

LUNA MV - scientific program 13 C(a, n)16 O: enriched 13 C solid target. Neutron detector Data taking at LUNA 400 k. V before 2018 22 Ne(a, n)25 Mg: 12 C(a, g)16 O: 12 C enriched 22 Ne gas target. Neutron detector. solid target depleted in target and 12 C beam. 12 C+12 C: 13 C and alpha beam or a jet gas solid state target. Gamma and particle detectors Technical developments on production and characterization of solid C targets and on neutron detectors already started Possible commissioning measurement: 14 N(p, g)15 O: Goal: obtain scientific results of high impact but reduced risk immediately after commissioning phase.

LUNA MV project-commissioning measurement 14 N(p, g)15 O Use of neutrino flux as a probe of solar interior composition (metallicity) CNO neutrino play a key role: Borexino can detect them Necessary to better constrain nuclear physics inputs i. e. 14 N(p, g)15 O

LUNA MV project-commissioning measurement 14 N(p, g)15 O Already measured at LUNA 400 k. V down to 70 ke. V (110 ke. V with angular distribution). Target production known. R matrix extrapolation to Gamow peak energies affected by high uncertainties at higher energies (g. s. transition in figure) Measure in the range 200 ke. V - 1. 5 Me. V with both accelerators and same experimental setup to minimize systematic effects Study angular distribution with HPGe detectors in far geometry. Reduce the nuclear physics uncertainty from 7% to 5% and measure CNO neutrinos (15 O) with 10% uncertainty allow to determine solar metallicity with 17% accuracy (now >30%)

LUNA MV- organigram PI Guglielmetti RAE Gazzana Technical coordinator Gazzana Coord of authorization request Prati GLIMOS Gazzana Building & Infrastructure Accelerator Imbriani/Junker Scientific equipments Formicola Civil engineering Martella, Leonzi, Di Sabatino Accelerator advisory committee Gialanella, Giuntini Strieder, Robertson Gas target beam line Prati Gazzana Plants Neutron simulation Trezzi RUP support office De. Dominicis, Gialanella, Lucente, Sartini Solid target beam line Imbriani Gamma detectors & DAQ Menegazzo Neutron detectors & DAQ Paticchio

The LUNA collaboration • A. Best, A. Boeltzig*, G. F. Ciani, A. Formicola, S. Gazzana, I. Kochanek, M. Junker, L. Leonzi | INFN LNGS /*GSSI, Italy • D. Bemmerer, M. Takacs, T. Szucs | HZDR Dresden, Germany • C. Broggini, A. Caciolli, R. Depalo, R. Menegazzo, D. Piatti | Università di Padova and INFN Padova, Italy • C. Gustavino | INFN Roma 1, Italy • Z. Elekes, Zs. Fülöp, Gy. Gyurky| 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, D. Trezzi | Università di Milano and INFN Milano, Italy • 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. 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