Carlo Broggini, INFN-Padova

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Carlo Broggini, INFN-Padova
Neutrino cross sections for Astrophysics
Gamow Factor
Astrophysical Factor

• Nuclear Burning
• in Stars
• s(Estar)

s(E) S(E) e2ph E-1
2ph 31.29 Z1Z2 ?m/Ecm
m m1m2 / (m1m2)
?
Reaction Rate(star) ?
F(E) s(E) dE
Extrap.
Meas.
Gamow Peak
s
Maxwell Boltzmann
s
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LUNA
INFN - Laboratori Nazionali del Gran
Sasso R.Bonetti, C.Broggini,F.Confortola,
P.Corvisiero,H.Costantini, J. Cruz, A.Formicola,
Z. Fülöp, G.Gervino, A.Guglielmetti, C.Gustavino,
G. Gyurky, G. Imbriani, A.P.Jesus, M.Junker,
A.Lemut, R.Menegazzo, A.Ordine, P.Prati, V.Roca,
D.Rogalla, C.Rolfs, M.Romano, C.RossiAlvarez,
F.Schümann, O.Straniero,F.Strieder,
E.Somorjai,F.Terrasi,H.P.Trautvetter,
S.Zavatarelli
INFN Genova, LNGS, Milano, Napoli, Padova,
Torino Inst.Physik mit Ionenstrahlen,
Ruhr-Universität Bochum (GE) Centro de Fisica
Nuclear da Universidade de Lisboa
(Portugal) Atomki Debrecen (Hungary)
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F?
Fn

0.7 m-2 h-1
? 3?10-6 cm-2 s-1
luna
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LUNA2 (400 kV)
LUNA1 ( 50 kV)
Voltage Range 50-400 kV
Output Current 1 mA (_at_ 400 kV)


Absolute Energy error 300 eV Beam
energy spread lt100 eV Long term stability (1 h)
5 eV Terminal Voltage ripple 5 Vpp Ge detector
Voltage Range 1 - 50 kV Output Current 1
mA Beam energy spread 20 eV Long term stability
(8 h) 10-4 Terminal Voltage ripple 5 10-5
5
2004-2005
measured
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3He (3He,2p)4He
Q 12.86 MeV
Epmax 10.7 MeV
? from the Sun
?min
0.02 pb
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14N(p,g)15O
Q7.3 MeV
? Elt1.2 MeV
? Elt1.7 MeV

• ?

F
S1,14
?
cno
cno

• Globular Cluster Age

S(0)3.5-1.60.4 keV b (Ad98)
S(0)3.2-0.80.8 keV b (An99)
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• High energy solid target HpGe

gamma spectrum of 14N(p,g)15O at Ep140 keV
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14N(p,g)15O
g.s. transition
S gs(0)1.550.34 keV b (Schr87)
S gs(0)0.080.130.06 keV b (Ang01)
S gs(0)0.250.06 keV b (LUNA)
s
S tot(0)1.70.1 0.2 keV b (LUNA)
0.5
?cno 0.5
Globular cluster age 0.7-1 Gy
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• Low energy gas target BGO

Ebeam 80 keV
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• LUNA has shown that it is

s(Estar)
possible to measure
? from he Sun

• Past

3He (3He,2p)4He
?

• Present

14N(p,g)15O
,Globular cluster age
cno

• Future

3He(?,g)7Be
the Sun
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D(p,g)3He
Q 5.5. MeV

• D abundance
• Proto-stars
• Big-bang

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14N(p,g)15O
6.79 MeV transition
S 6.79(0)1.410.02 keV b (Schr87)
S 6.79(0)1.630.17 keV b (Ang01)
S 6.79(0)1.350.050.08 keV b (LUNA)

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