LUNA II Foto Umax = 50 - 400 kV
LUNA 400 kV at LNGS: Imax = 650 AEmax = 0.07 keV
allowed beams : protons, alphas
LUNA 2 site
LUNA 50kV
LUNA 400kV
LUNA underground Laboratories
Near the Gamow peak:
BGO detector
4 summing chrystal
8000 2000 6000 4000 0
10
30
50 2000 Channels20000 seeds
Energy / keV
14N(p,)15OSimulation
BGO detector
Energy / keV
E>5.5 MeV:4.4 cts/MeV/day
2000 4000 6000 8000
Background Spectrum Measured Underground
10 0
10 2
10 4
10 6
4096 Channels12.5 days
target
beam
calorimeter
D(p,g)
Ecm= 10 keV
D(p,)3HeLUNA data
below the Gamow peak
Ecm= 6 keV
D(p,)3He
= 0.01 pbarn Viviani et al. PRC61 (2000)
D(p,)3He
P + d all
Beam calorimeter
beamcoolin
g syste
m
gas from trap
gas to pumps heater
cold sidehot side
T = const.
W0 = R-1 (Th-Tc) + Wloss
Wbeam+ W = R-1 (Th-Tc) + Wloss
Wbeam = W0 –W
Ibeam = Wbeam/Ebeam
without beam:
with beam:(Wloss = const. at fixed T)
heater (transistor, resistor, ..) provides W
T is kept constant by a feedback system
windowless gas target
I I I
I
I I
zeolite trapgas cleaner
beam collimators
turbopump
roots blowers
target chamber
p=0.3 mbar
Fig 1 nuovo acceleratore da 400 kVFig 2 mappa laboratori sotterraneiFig 3 rivelatore BGO usato per la p+dFig 4 rivelatore BGO + stadi pompaggio gas targetFig 5 in primo piano stadio pompaggio gas target, in alto rivelatore BGO (il fascio di protoni “entra” dal bassoFig 6 vista laterale di stadio pompaggio + BGOFig 7 uno spettro dei fotoni da 5.5 MeVFig 8 come sopraFig 9 le misure esistentiFig 10 dettagli sul calorimetro per la misura della corrente del fascio (da una misura di potenze termica depositata, nota l’energiaFig 11 shema gas target con ricircolo deuterio