ENTRY L0153 20101014 L014L015300000001 SUBENT L0153001 20101014 L014L015300100001 BIB 13 61 L015300100002 TITLE Differential polarization of photoneutrons from L015300100003 deuterium L015300100004 AUTHOR (R.Nath,F.W.K.Firk,H.L.Schultz) L015300100005 INSTITUTE (1USAYAL) L015300100006 REFERENCE (J,NP/A,194,49,1972) L015300100007 FACILITY (LINAC,1USAYAL) Experiment performed at 65 MeV Yale L015300100008 University Electron Linear Accelerator. L015300100009 SAMPLE Two set of samples containing deuterium were used. L015300100010 1. Deuterated polyethylene (C-2H2), one with diameter L015300100011 of 12.7 cm and thickness of 2.06 cm, the second L015300100012 with diameter 7.18 cm and thickness of 4.57 mm. L015300100013 2. Heavy water (2H2-O) in a a thin plastic cylindricalL015300100014 bottle with 7.62 cm diameter and 12.70 cm high. L015300100015 For background measurement, targets with light water L015300100016 and standard polyethylene with identical dimensions L015300100017 as deuterated targets were used. L015300100018 DETECTOR (MAGSP) Solenoid with length of 1.2m, inside L015300100019 diameter of 7.5 cm and maximal field of 5000 Oersted L015300100020 was used for neutron spin precession. After a flight L015300100021 path of 26m, photoneutrons were scattered from L015300100022 a polarization analyser (liquid helium or graphite). L015300100023 (SCIN) Four Pilot B plastic scintillators each L015300100024 coupled to 12.7 cm diam phototubes are used as L015300100025 neutron detectors to observe left-right asymmetries L015300100026 of neutrons scattered from the helium polarization L015300100027 analyser. Most of the data are obtained using two L015300100028 pilot-B plastic scintillators (12.70 cm diam x 15.24 cmL015300100029 thick) each coupled to an RCA 7046 photo-multiplier L015300100030 tube placed in the reaction plane at lab angles of L015300100031 +-130 deg and at a distance of 27.6 cm from the centre L015300100032 of the helium analyser. Other two neutron detectors L015300100033 12.70 cm diam x 7.62 cm thick with pilot-B plastic L015300100034 scintillators each coupled to an Amperex 58 AVP L015300100035 photomultiplier tube were used either in an up-down L015300100036 geometry or in a left-right geometry at lab angles L015300100037 of +-70deg. L015300100038 METHOD (LRASY) The polarization of the photo-neutrons is L015300100039 determined by observing the asymmetry in their L015300100040 scattering from a liquid-helium cryostat or a L015300100041 graphite cylinder placed at the end of a 25 m flight L015300100042 path. L015300100043 (TOF) Photoneutron energy was determined by time-of- L015300100044 flight over flight path of 26 m. L015300100045 INC-SOURCE (BRST) Electrons with energy of 65 MeV striked a 250 L015300100046 mu-m thick tungsten foil and produce bremsstrahlung L015300100047 photons with a maximum energy of 65 MeV. The L015300100048 electrons which pass through the foil were absorbed L015300100049 in a 10.80 cm thick x 6.35 cm diam electrically L015300100050 insulated aluminium cylinder. Maximum beam current L015300100051 was 2 A with pulse duration of 10 ns and repetition L015300100052 rate of 330 Hz. L015300100053 ANALYSIS Polarisation was determined from left-right asymetry L015300100054 after subtraction of background contribution determinedL015300100055 in measurement with light water and non-deuterated L015300100056 polyethylene L015300100057 ERR-ANALYS (DATA-ERR) No information given. Given uncertainties L015300100058 are most probably statistical uncertainties L015300100059 CORRECTION Corrected for target scattering effects, correction L015300100060 amounts to 10% at 15 MeV neutron energy and to 20% L015300100061 at the lowest energy. L015300100062 HISTORY (20101014C) Compiled by S.H. L015300100063 ENDBIB 61 0 L015300100064 NOCOMMON 0 0 L015300100065 ENDSUBENT 64 0 L015300199999 SUBENT L0153002 20101014 L014L015300200001 BIB 3 3 L015300200002 REACTION (1-H-2(G,N)1-H-1,,POL/DA) L015300200003 STATUS (CURVE) Data taken from fig. 5 of the reference L015300200004 MISC-COL (MISC) Energy of the photoneutron L015300200005 ENDBIB 3 0 L015300200006 COMMON 1 3 L015300200007 ANG L015300200008 ADEG L015300200009 90.0 L015300200010 ENDCOMMON 3 0 L015300200011 DATA 4 9 L015300200012 EN DATA DATA-ERR MISC L015300200013 MEV NO-DIM NO-DIM MEV L015300200014 7.31 -0.107 0.014 2.52 L015300200015 7.86 -0.096 0.012 2.79 L015300200016 11.62 -0.065 0.017 4.63 L015300200017 14.07 -0.046 0.010 5.84 L015300200018 16.09 -0.081 0.012 6.83 L015300200019 18.64 -0.070 0.014 8.08 L015300200020 21.01 -0.034 0.015 9.24 L015300200021 24.74 -0.089 0.014 11.08 L015300200022 32.87 -0.032 0.024 15.07 L015300200023 ENDDATA 11 0 L015300200024 ENDSUBENT 23 0 L015300299999 SUBENT L0153003 20101014 L014L015300300001 BIB 3 3 L015300300002 REACTION (1-H-2(G,N)1-H-1,,POL/DA) L015300300003 STATUS (CURVE) Data taken from fig. 5 of the reference L015300300004 MISC-COL (MISC) Energy of the photoneutron L015300300005 ENDBIB 3 0 L015300300006 COMMON 1 3 L015300300007 ANG L015300300008 ADEG L015300300009 45.0 L015300300010 ENDCOMMON 3 0 L015300300011 DATA 6 11 L015300300012 EN +EN-ERR -EN-ERR DATA DATA-ERR MISC L015300300013 MEV MEV MEV NO-DIM NO-DIM MEV L015300300014 9.90 -9.8 1.5 4.01 L015300300015 11.66 -10.4 1.3 5.02 L015300300016 13.38 -9.2 1.4 6.02 L015300300017 14.16 -7.2 0.8 6.47 L015300300018 14.96 -6.0 1.1 6.93 L015300300019 15.55 -3.4 1.1 7.27 L015300300020 16.55 -2.8 0.9 7.85 L015300300021 18.96 -0.7 0.9 9.24 L015300300022 21.05 -0.5 1.1 10.45 L015300300023 23.29 -0.8 1.1 11.74 L015300300024 26.23 2.76 1.95 3.1 1.5 13.44 L015300300025 ENDDATA 13 0 L015300300026 ENDSUBENT 25 0 L015300399999 ENDENTRY 3 0 L015399999999