ENTRY M0485 20230106 M122M0485 0 1 SUBENT M0485001 20230106 M122M0485 1 1 BIB 18 63 M0485 1 2 TITLE Evidence of 2+ state from the He-4(g,n)He-3 reaction. M0485 1 3 AUTHOR (C.K.MALCOM,D.V.WEBB,Y.M.SHIN,D.M.SKOPIK) M0485 1 4 REFERENCE (J,PL/B,47,433,1973) M0485 1 5 INSTITUTE (1CANSAS) M0485 1 6 FACILITY (LINAC,1CANSAS) M0485 1 7 INC-SOURCE (BRST) M0485 1 8 METHOD (TOF) M0485 1 9 DETECTOR (SCIN) M0485 1 10 SAMPLE The target was a conventional 7 liter, liquid helium M0485 1 11 dewar. While runnung, the dewar was pressured to M0485 1 12 0.034 atm to minimize the loss rate and reduce M0485 1 13 thermal density variations. M0485 1 14 PART-DET (N) M0485 1 15 ANALYSIS (INTAD) With reasonably high statistical accuracy M0485 1 16 the reaction cross section simultaneously have been M0485 1 17 measured at five laboratory angles between 30 and M0485 1 18 142 degrees. Differential cross sections were M0485 1 19 obtained by comparing the He-4(g,n)He-3 and M0485 1 20 H-2(g,n)H-1 cross sections. The latter were obtained M0485 1 21 from alternating runs with D(2)O and H(2)O in an M0485 1 22 identical target configuration as that used for M0485 1 23 helium. for the deuterium cross section, the M0485 1 24 experimental results were normalized to the M0485 1 25 calculation of Partovi. Differential cross sections M0485 1 26 were used to obtain the total cross section. M0485 1 27 MONITOR (1-H-2(G,N)1-H-1,,SIG) M0485 1 28 MONIT-REF (,Y.M.Shin+,J,NP/A,154,482,1970) Experimental data M0485 1 29 on the H-2(g,n) reaction cross section. M0485 1 30 (,F.Partovi,J,AP,27,79,1964) Calculation for the M0485 1 31 H-2(g,n) reaction cross section. M0485 1 32 ERR-ANALYS (ERR-S) The statistical errors are presented only. M0485 1 33 CORRECTION The photoneutron energy spectra were first M0485 1 34 corrected for counting losses (< 2%), and M0485 1 35 background was substracted. corrections for neutron M0485 1 36 scattering and absorption within the target were M0485 1 37 made with a monte-carlo method. the contribution M0485 1 38 of neutrons from other competing channels was M0485 1 39 assessed by comparing data taken at lower incident M0485 1 40 electron energies. the other neutron producing M0485 1 41 channels, contributing < 10% to the spectra, were M0485 1 42 substracted where necessary from the data. M0485 1 43 COMMENT The He-4(g,n)He-3 differential cross section has M0485 1 44 been simultaneously measured at five laboratory M0485 1 45 angles between 30 and 142 degrees, from threshold M0485 1 46 to 110 MeV. The asymmetry in the angular distribution M0485 1 47 from 24 to 70 MeV has been extracted and found to M0485 1 48 have sign changes at energies which are in accord M0485 1 49 with the previous experiments. The total photo- M0485 1 50 neutron cross section has been observed to be close M0485 1 51 to the known (g,p) cross section. From the energy M0485 1 52 dependence of the asymmetry coefficient a 2+ state M0485 1 53 in He-4 at energy of about 35 MeV has been confirmed. M0485 1 54 CRITIQUE EN-CM in the capture to Fig.1 is the mistake. M0485 1 55 HISTORY (19910218C) M0485 1 56 (20050609A) Corrected by V.Varlamov: M0485 1 57 Dates corrected from two to four digits including M0485 1 58 those in REFERENCE and HISTORY, lower case, M0485 1 59 volume and page numbers in REFERENCE corrected M0485 1 60 322,47 to 47,433. M0485 1 61 (20050901A) Corrected by V.Varlamov: BRA substituted M0485 1 62 by BRS in line REACTION of SUBENT 002. M0485 1 63 (20230106A) Corrected by V.Varlamov: CRITIQUE, STATUS, M0485 1 64 REACTION, (EN-CM) -> EN in SUBENT 002. M0485 1 65 ENDBIB 63 0 M0485 1 66 NOCOMMON 0 0 M0485 1 67 ENDSUBENT 66 0 M0485 199999 SUBENT M0485002 20230106 M122M0485 2 1 BIB 3 5 M0485 2 2 REACTION (2-HE-4(G,N)2-HE-3,,SIG) M0485 2 3 STATUS (CURVE) Data from Fig. 1 of M0485 2 4 Phys.Lett.,B47(1973)433. M0485 2 5 HISTORY (20230106A) Corrected by V.Varlamov: REACTION, M0485 2 6 (EN-CM) -> EN. M0485 2 7 ENDBIB 5 0 M0485 2 8 NOCOMMON 0 0 M0485 2 9 DATA 3 32 M0485 2 10 EN DATA ERR-S M0485 2 11 MEV MB MB M0485 2 12 25. 2.05 .1 M0485 2 13 26. 2.07 .1 M0485 2 14 27. 2.06 .07 M0485 2 15 28. 2.01 .06 M0485 2 16 29. 1.95 .07 M0485 2 17 30. 1.84 .07 M0485 2 18 31. 1.7 .06 M0485 2 19 32. 1.6 .06 M0485 2 20 33. 1.49 .05 M0485 2 21 34. 1.37 .04 M0485 2 22 35. 1.29 .04 M0485 2 23 36. 1.21 .02 M0485 2 24 37. 1.11 .02 M0485 2 25 38. 1.08 .02 M0485 2 26 39. .99 .01 M0485 2 27 40. .92 .01 M0485 2 28 41. .86 .01 M0485 2 29 42. .8 .01 M0485 2 30 44. .71 .005 M0485 2 31 46. .63 .005 M0485 2 32 48. .56 .005 M0485 2 33 50. .5 .005 M0485 2 34 52. .46 .005 M0485 2 35 54. .42 .005 M0485 2 36 56. .4 .005 M0485 2 37 58. .36 .005 M0485 2 38 60. .34 .005 M0485 2 39 62. .31 .005 M0485 2 40 64. .29 .005 M0485 2 41 66. .29 .005 M0485 2 42 68. .25 .005 M0485 2 43 70. .22 .005 M0485 2 44 ENDDATA 34 0 M0485 2 45 ENDSUBENT 44 0 M0485 299999 ENDENTRY 2 0 M048599999999