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

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

3. 17O(p,a)14N and 18O(p,a)15N reactions
Q = 4 MeV
Two narrow resonances at 95 and 152 keV
Main goals:
rescan excitation function
95 keV resonance (strength and energy)
Measure below 70 keV
Q = 1.2 MeV
Two narrow resonances at 70 and 193 keV
Main goal:
70 keV resonance

4. 17O(p,a)14N and 18O(p,a)15N reactions
proton beam from LUNA 400 kV
enriched 17O or 18O targets
8 silicon detectors
foils of Al Mylar to stop backscattered protons low alpha particle energy ( keV for 17O(p,a)14N reaction)
Silicon detector
Solid target position

5. The 17O(p,a)14N reaction: 70 keV res
PRELIMINARY
Very preliminary analysis favours a larger strength value compared with literature
If confirmed, it would have an astrophysical impact

6. The 18O(p,a)15N reaction PRELIMINARY
Data taking completed. Data analysis on going
PRELIMINARY
152 keV resonance
334 keV resonance
216 keV resonance
In agreement with previous data
Might improve precision on resonance energy and strength
95 keV resonance strength: precision about 10% (20-30% literature)
energy determined with 0.5 keV precision (2.2 keV literature)
60 keV measured with about 20% statistical uncertainty

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

8. The 22Ne(p,g)23Na reaction
The “red” resonances have been directly observed for the first time
For the resonances at 71, 105 and 215 keV 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 res. plus DC from 200 to 360 keV)

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

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

11. LUNA MV project
Dimensions of the hall: 27x11x5 m3
OPERA decommissioning started in Jan Removed bricks out of , electronics, cooling system and some mechanical parts.
Should be finished by October 2016 (S. Gazzana link to LUNA MV)

12. LUNA MV project Accelerator:
Intense H+, 4He+, 12C+ e 12C++ beams in the energy range: 350 keV-3.5 MeV. 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 On March 18th the INFN executive board approved the tendering. Tender published on April 24th 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

14. LUNA MV project Building & shielding:
GEANT4 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, B4C concrete)
Possibility of multi layer configurations. Use HDPe granulate available at LNGS?

15. 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)

16. LUNA MV - scientific program
13C(a,n)16O: enriched 13C solid target. Neutron detector
Data taking at LUNA 400 kV before 2018
22Ne(a,n)25Mg: enriched 22Ne gas target. Neutron detector.
12C(a,g)16O: 12C solid target depleted in 13C and alpha beam or a jet gas target and 12C beam.
12C+12C: 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: 14N(p,g)15O:
Goal: obtain scientific results of high impact but reduced risk immediately after commissioning phase.

17. LUNA MV project-commissioning measurement 14N(p,g)15O
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.
14N(p,g)15O

18. LUNA MV project-commissioning measurement 14N(p,g)15O
Already measured at LUNA 400 kV down to 70 keV (110 keV 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 keV MeV 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 (15O) with 10% uncertainty allow to determine solar metallicity with 17% accuracy (now >30%)

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

20. 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 Roma1, 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