ENTRY C2506 20210518 C204C250600000001
SUBENT C2506001 20210518 C204C250600100001
BIB 11 51 C250600100002
TITLE Be(p,2n)B8 reaction as a neutrino source C250600100003
AUTHOR (N.E.Davison,M.J.Canty,D.A.Dohan,A.Mcdonald) C250600100004
INSTITUTE (1CANMNA) C250600100005
REFERENCE (J,PR/C,10,50,1974) C250600100006
#doi:10.1103/PhysRevC.10.50 C250600100007
FACILITY (CYCLO,1CANMNA) C250600100008
SAMPLE A self-supporting beryllium metal foil of C250600100009
9.1 mg/cm2 thickness. C250600100010
DETECTOR (NAICR) Two 5.1 x 3.2 cm NaI crystals operated in C250600100011
fast-slow coincidence. C250600100012
METHOD (COINC,GSPEC,EXTB) The proton current 60 nA was C250600100013
collected in a Faraday cup. The beam was pulsed: C250600100014
0.7 sec irradiation interval, a 10.0 sec counting C250600100015
interval. The target was mounted at the center of an C250600100016
annular aluminum stopper 10 cm long, and with a wall C250600100017
thickness of 3.8 cm. Pairs of 511 keV quanta were C250600100018
detected in two NaI crystals operated in fast-slow C250600100019
coincidence. The coincidence resolving time of the C250600100020
detectors was 12 nsec full width at half maximum. C250600100021
The absolute efficiency of the apparatus as a detector C250600100022
of B-8 positrons was obtained in two stages: (i) The C250600100023
distribution of the stopped positrons in the aluminum C250600100024
stopper was calculated; and (ii) a Na-22 source of C250600100025
known strength was used to measure experimentally the C250600100026
efficiency. C250600100027
CORRECTION Correction was made: C250600100028
- to take into account those B-8 nuclei which recoil C250600100029
out of the target at angles such as to be lost; this C250600100030
correction is approximately 4% at Ep = 30 MeV and C250600100031
12% at Ep =47.5 MeV, C250600100032
- for positron annihilation in flight. ' C250600100033
ERR-ANALYS (ERR-T) The errors on the cross sections were C250600100034
obtained by adding in quadrature statistical errors in C250600100035
the number of counts attributed to B-8, statistical C250600100036
errors in the background subtraction, inaccuracy in C250600100037
the estimation of time at which the beam was cut off. C250600100038
(ERR-1) uncertainty in the strength of the Na-22 sourceC250600100039
used to obtain the stopper efficiency (5%), C250600100040
(ERR-2) statistical uncertainty in the efficiency C250600100041
calibration (2%), C250600100042
(ERR-3) inaccuracies in the range formulas and the C250600100043
computation of the distribution of positrons stopped inC250600100044
the aluminum stopper (5%), C250600100045
(ERR-4) inaccuracy in the estimation of time at which C250600100046
the beam was cut off (3%), C250600100047
(ERR-5) uncertainty in target thickness (5%), C250600100048
(ERR-6) uncertainty in the correction for annihilation C250600100049
in flight (2%), C250600100050
(ERR-7,2.,6.) uncertainty in the correction for lost C250600100051
recoil 8B nuclei (2% at Ep=30 MeV, 6% at Ep=47.5 MeV). C250600100052
HISTORY (20210518C) OG C250600100053
ENDBIB 51 0 C250600100054
COMMON 6 3 C250600100055
ERR-1 ERR-2 ERR-3 ERR-4 ERR-5 ERR-6 C250600100056
PER-CENT PER-CENT PER-CENT PER-CENT PER-CENT PER-CENT C250600100057
5. 2. 5. 3. 5. 2. C250600100058
ENDCOMMON 3 0 C250600100059
ENDSUBENT 58 0 C250600199999
SUBENT C2506002 20210518 C204C250600200001
BIB 3 4 C250600200002
REACTION (4-BE-9(P,2N)5-B-8,,SIG) C250600200003
DECAY-DATA (5-B-8,0.762SEC,B+) C250600200004
STATUS (CURVE) Fig.3 in Phys.Rev.C,10,50,1974 was digitized C250600200005
by GSYS2.4.7. C250600200006
ENDBIB 4 0 C250600200007
NOCOMMON 0 0 C250600200008
DATA 3 9 C250600200009
EN DATA ERR-T C250600200010
MEV MB MB C250600200011
22.021 0.016 0.012 C250600200012
25.088 0.058 0.007 C250600200013
30.104 0.163 0.013 C250600200014
30.113 0.195 0.012 C250600200015
35.182 0.282 0.017 C250600200016
40.125 0.237 0.017 C250600200017
45.093 0.274 0.018 C250600200018
47.586 0.223 0.017 C250600200019
47.604 0.286 0.017 C250600200020
ENDDATA 11 0 C250600200021
ENDSUBENT 20 0 C250600299999
ENDENTRY 2 0 C250699999999