ENTRY 23036 20121021 22332303600000001
SUBENT 23036001 20121021 22332303600100001
BIB 13 98 2303600100002
TITLE .Measurement of the D(n,2n)p reaction cross section 2303600100003
up to 30 MeV 2303600100004
AUTHOR (J.-M.Laborie, X.Ledoux, C.Varignon, R.Lazauskas, 2303600100005
B.Morillon, G.Belier, D.Dore, N.Arnal) 2303600100006
INSTITUTE (2FR BRC) CEA/DAM, Ile de France - DPTA/SPN, 2303600100007
Bruyere-le-Chatel, France. J.-M.Laborie, X.Ledoux, 2303600100008
C.Varignon, R.Lazauskas, B.Morillon, G.Belier, 2303600100009
N.Arnal 2303600100010
(2FR SAC) CEA/Saclay DAPNIA/SPhN, Gif-sur-Yvette, 2303600100011
France. D.Dore 2303600100012
REFERENCE (J,EPJ/A,48,87,2012) Data in Tables. 2303600100013
#doi:10.1140/epja/i2012-12087-4 2303600100014
(C,2007NICE,1,437,200704) ND2007 report #313. 2303600100015
#doi:10.1051/ndata:07313 2303600100016
Graph of only preliminary data. 2303600100017
<A,2007NICE,,(#313),200704> Abstracts, analogous to 2303600100018
main reference 2303600100019
REL-REF (I,,C.Varignon+,J,NIM/B,248,329,2006) Description 2303600100020
of 7 MV tandem accelerator 2303600100021
FACILITY (VDGT,2FR BRC) Tandem 7 MV accelerator, beam nominal 2303600100022
frequency 2.5 MHz 2303600100023
INC-SOURCE (D-D,P-T) 5 - 10 MeV neutrons 2303600100024
(D-T) 20 - 25 MeV neutrons 2303600100025
INC-SPECT .Monoenergetic neutrons corresponding to the above 2303600100026
given source reactions and broad low-energy tail. 2303600100027
TOF technique was employed to select the neutrons 2303600100028
corresponding to the monoenergetic peak. 2303600100029
DETECTOR (SCIN) A 4pi neutron detector called CARMEN is a large 2303600100030
spherical neutron detector, constituted of two 2303600100031
independent vertical hemispheres, 60cm outer-radius, 2303600100032
15cm inner radius, each one filled with less than 2303600100033
0.5 m3 of gadolinium-loaded scintillating liquid 2303600100034
(BC521) used for counting the two outgoing neutrons. 2303600100035
Efficiency measured by 252-Cf trigger is 80% 2303600100036
diminishing to 75% at 20-25 MeV neutron energy. 2303600100037
(SOLST) 12.5 cm diameter, 5cm thick NE213 scintillation2303600100038
detectors were used to monitor neutron beam:2 2303600100039
one - to measure neutron flux, other - measure the 2303600100040
energy of incident neutrons. 2303600100041
NE213 neutron flux monitor was calibrated at seven 2303600100042
neutron energies between 5.8 and 22MeV at the German 2303600100043
Lab.of Neutron Metrology (PTB).Efficiency was measured 2303600100044
for the same low-energy threshold as the one used in 2303600100045
the present experiment, with an accuracy obtained 2303600100046
reaches 2% at energies up to 12MeV and 4% beyond this 2303600100047
point. 2303600100048
METHOD (TOF) Used for separation of sharp neutron beam from 2303600100049
the broad background . 2303600100050
Flight path 13m from the neutron production target. 2303600100051
SAMPLE .Active deuteron target as 12.5cm diameter x 5cm thick 2303600100052
(2x2inch) aluminum cell containing the 103 cm3 2303600100053
scintillating liquid. Detector placed in the reaction 2303600100054
chamber of CARMEN . 2303600100055
To take into account the (n,2n) reactions on elements 2303600100056
B, C, Si, O, Al ( present inside or in the vicinity of 2303600100057
the active target volume), dedicated runs were done 2303600100058
with a C6H6 hydrogenated target, with the same 2303600100059
dimensions and scintillating properties as the 2303600100060
deuterated one. 2303600100061
C6D6 target: 4.06E+22 H-2 atoms per cm**3, 3.55E+20 2303600100062
H-1 atoms per cm**3, 4.10E+22 C atoms per cm**3. 2303600100063
C6H6 target: 4.0955E+22 H-1 atoms per cm**3, 4.10E+22 2303600100064
C atoms per cm**3. 2303600100065
CORRECTION The Monte Carlo simulation code SIM was used to 2303600100066
calculate correction factors taking into account the 2303600100067
energy resolution, the spatial neutron beam profile, 2303600100068
detailed description of the target, every possible 2303600100069
reaction, the energy-angle correlations between the 2303600100070
two neutrons and the proton. 2303600100071
Contribution of C6H6 was subtracted. 2303600100072
Detector efficiency was checked by Cf-252 sample and 2303600100073
MCNP code calculations. 2303600100074
For neutron absorption in the target - transmission 2303600100075
was measured by measuring the flux with and without 2303600100076
the target. It varies between 50% to 70%, depending on 2303600100077
the incident energy. 2303600100078
The resulting correction factor from: 2303600100079
- correction for the finite-geometry effects of the 2303600100080
target; 2303600100081
- correction for the 2H(n,2n)p reaction losses due to 2303600100082
the proton recoil threshold; 2303600100083
- correction for the extra 2H(n,2n) reactions occurring2303600100084
in the expansion chamber and detected in the active 2303600100085
volume. 2303600100086
Total correction was applied to the measured finite- 2303600100087
geometry cross-section data and amounts to 4.1-4.3% for2303600100088
20-25MeV incident neutron energies, varies from 12.6% 2303600100089
to 16.2% for 5-8 MeV incident neutron energies . 2303600100090
HISTORY (20081012C) SM 2303600100091
(20101106A) SD: doi for ref. 2007NICE,1,437,2007 2303600100092
corrected. Author's name corrected (D.Doree => D.Dore) 2303600100093
Ref. on NIM/B,248 moved to REL-REF 2303600100094
In Subent 002 ERR-SYS renamed as ERR-T according to 2303600100095
description in the article. Precision of the data are 2303600100096
corrected. 2303600100097
(20121021A) M.M. Ref. J,EPJ/A,48,87,2012 was added. 2303600100098
Digitized data were replaced by data of Tables. 2303600100099
Subent 003 was added. BIB information was added. 2303600100100
ENDBIB 98 0 2303600100101
NOCOMMON 0 0 2303600100102
ENDSUBENT 101 0 2303600199999
SUBENT 23036002 20121021 22332303600200001
BIB 6 32 2303600200002
REACTION (1-H-2(N,2N)1-H-1,,SIG) 2303600200003
ERR-ANALYS (ERR-T) Total uncertainty 2303600200004
(ERR-S,0.9,4.5) Statistical uncertainty 2303600200005
Uncertainties of normalization: 2303600200006
(ERR-1) Uncertainty due to monoenergetic peak area on 2303600200007
the tof spectrum. 2303600200008
(ERR-2) Uncertainty due to NE213 detection efficiency. 2303600200009
(ERR-3,3.,5.) Uncertainty due to target transmission. 2303600200010
(ERR-4,4.2,5.8) Uncertainty due to total incident 2303600200011
neutron fluence. 2303600200012
Uncertainties of reaction rate: 2303600200013
(ERR-5,4.9,6.7) Uncertainty due to experimental 2303600200014
reaction rate for one neutron. 2303600200015
(ERR-6,0.5,1.8) Uncertainty due to CARMEN efficiency 2303600200016
for 252Cf neutrons. 2303600200017
(ERR-7,5.4,7.2) Uncertainty due to reaction rate 2303600200018
for given fluence. 2303600200019
All the points are considered except for the one at 2303600200020
6.8MeV for which the uncertainty is much larger (13.5%)2303600200021
because of low statistics. 2303600200022
INC-SPECT Energy resolution is less 2.% . 2303600200023
STATUS (TABLE) Table 5 of J,EPJ/A,48,87,2012. 2303600200024
Fig.4 of C,2007NICE,1,437,2007 - prelim.data. 2303600200025
COMMENT Of authors. Two values measured at 6.8MeV, for two 2303600200026
distinct campaigns, agree well within the 68% C.L. 2303600200027
uncertainties, indicating a good repeatability of the 2303600200028
measurements. 2303600200029
HISTORY (20110206A) SD: ERR-SYS renamed as ERR-T according to 2303600200030
description in the article. Precision of the data are 2303600200031
corrected. 2303600200032
(20121021) Digitized data were replaced by data of 2303600200033
table. ERR-ANALYS was updated. 2303600200034
ENDBIB 32 0 2303600200035
COMMON 2 3 2303600200036
ERR-1 ERR-2 2303600200037
PER-CENT PER-CENT 2303600200038
2. 2. 2303600200039
ENDCOMMON 3 0 2303600200040
DATA 4 7 2303600200041
EN EN-ERR DATA ERR-T 2303600200042
MEV MEV MB MB 2303600200043
5.54 0.08 57.6 3.3 2303600200044
5.81 0.09 60.5 3.4 2303600200045
6.34 0.10 74.9 4.2 2303600200046
6.83 0.10 74.6 4.2 2303600200047
6.83 0.15 82.6 11.2 2303600200048
7.23 0.15 85.5 6.2 2303600200049
7.75 0.15 98.6 7.2 2303600200050
ENDDATA 9 0 2303600200051
ENDSUBENT 50 0 2303600299999
SUBENT 23036003 20121021 22332303600300001
BIB 5 21 2303600300002
REACTION (1-H-2(N,2N)1-H-1,,SIG) 2303600300003
ERR-ANALYS (ERR-T) Total uncertainty 2303600300004
(ERR-S,1.1,4.8) Statistical uncertainty 2303600300005
Uncertainties of normalization: 2303600300006
(ERR-1) Uncertainty due to monoenergetic peak area on 2303600300007
the tof spectrum. 2303600300008
(ERR-2) Uncertainty due to NE213 detection efficiency. 2303600300009
(ERR-3,3.,5.) Uncertainty due to target transmission. 2303600300010
(ERR-4,5.5,6.7) Uncertainty due to total incident 2303600300011
neutron fluence. 2303600300012
Uncertainties of reaction rate: 2303600300013
(ERR-5,6.4,9.6) Uncertainty due to experimental 2303600300014
reaction rate for one neutron, measured with CARMEN. 2303600300015
(ERR-6,0.5,1.8) Uncertainty due to CARMEN efficiency 2303600300016
for 252Cf neutrons. 2303600300017
(ERR-7,7.5,9.7) Uncertainty due to reaction rate 2303600300018
for given fluence. 2303600300019
INC-SPECT Energy resolution is less 2.% . 2303600300020
STATUS (TABLE) Table 6 of J,EPJ/A,48,87,2012. 2303600300021
Fig.4 of C,2007NICE,1,437,2007 - prelim.data. 2303600300022
HISTORY (20121021C) M.M. Subent was added. 2303600300023
ENDBIB 21 0 2303600300024
COMMON 2 3 2303600300025
ERR-1 ERR-2 2303600300026
PER-CENT PER-CENT 2303600300027
2. 4. 2303600300028
ENDCOMMON 3 0 2303600300029
DATA 4 11 2303600300030
EN EN-ERR DATA ERR-T 2303600300031
MEV MEV MB MB 2303600300032
20.2 0.4 172.4 14.1 2303600300033
21.2 0.4 153.7 11.8 2303600300034
21.6 0.4 128.9 10.9 2303600300035
21.8 0.3 142.6 11.0 2303600300036
21.8 0.3 136.3 10.1 2303600300037
21.8 0.4 131.8 12.1 2303600300038
22.4 0.3 134.1 10.9 2303600300039
23.0 0.3 132.1 11.5 2303600300040
23.5 0.3 154.4 12.2 2303600300041
24.1 0.3 141.6 13.8 2303600300042
24.7 0.3 141.8 11.0 2303600300043
ENDDATA 13 0 2303600300044
ENDSUBENT 43 0 2303600399999
ENDENTRY 3 0 2303699999999