ENTRY M0485 20230106 M048500000001 SUBENT M0485001 20230106 20230412 M048500100001 BIB 18 63 M048500100002 TITLE Evidence of 2+ state from the He-4(g,n)He-3 reaction. M048500100003 AUTHOR (C.K.MALCOM,D.V.WEBB,Y.M.SHIN,D.M.SKOPIK) M048500100004 REFERENCE (J,PL/B,47,433,1973) M048500100005 INSTITUTE (1CANSAS) M048500100006 FACILITY (LINAC,1CANSAS) M048500100007 INC-SOURCE (BRST) M048500100008 METHOD (TOF) M048500100009 DETECTOR (SCIN) M048500100010 SAMPLE The target was a conventional 7 liter, liquid helium M048500100011 dewar. While runnung, the dewar was pressured to M048500100012 0.034 atm to minimize the loss rate and reduce M048500100013 thermal density variations. M048500100014 PART-DET (N) M048500100015 ANALYSIS (INTAD) With reasonably high statistical accuracy M048500100016 the reaction cross section simultaneously have been M048500100017 measured at five laboratory angles between 30 and M048500100018 142 degrees. Differential cross sections were M048500100019 obtained by comparing the He-4(g,n)He-3 and M048500100020 H-2(g,n)H-1 cross sections. The latter were obtained M048500100021 from alternating runs with D(2)O and H(2)O in an M048500100022 identical target configuration as that used for M048500100023 helium. for the deuterium cross section, the M048500100024 experimental results were normalized to the M048500100025 calculation of Partovi. Differential cross sections M048500100026 were used to obtain the total cross section. M048500100027 MONITOR (1-H-2(G,N)1-H-1,,SIG) M048500100028 MONIT-REF (,Y.M.Shin+,J,NP/A,154,482,1970) Experimental data M048500100029 on the H-2(g,n) reaction cross section. M048500100030 (,F.Partovi,J,AP,27,79,1964) Calculation for the M048500100031 H-2(g,n) reaction cross section. M048500100032 ERR-ANALYS (ERR-S) The statistical errors are presented only. M048500100033 CORRECTION The photoneutron energy spectra were first M048500100034 corrected for counting losses (< 2%), and M048500100035 background was substracted. corrections for neutron M048500100036 scattering and absorption within the target were M048500100037 made with a monte-carlo method. the contribution M048500100038 of neutrons from other competing channels was M048500100039 assessed by comparing data taken at lower incident M048500100040 electron energies. the other neutron producing M048500100041 channels, contributing < 10% to the spectra, were M048500100042 substracted where necessary from the data. M048500100043 COMMENT The He-4(g,n)He-3 differential cross section has M048500100044 been simultaneously measured at five laboratory M048500100045 angles between 30 and 142 degrees, from threshold M048500100046 to 110 MeV. The asymmetry in the angular distribution M048500100047 from 24 to 70 MeV has been extracted and found to M048500100048 have sign changes at energies which are in accord M048500100049 with the previous experiments. The total photo- M048500100050 neutron cross section has been observed to be close M048500100051 to the known (g,p) cross section. From the energy M048500100052 dependence of the asymmetry coefficient a 2+ state M048500100053 in He-4 at energy of about 35 MeV has been confirmed. M048500100054 CRITIQUE EN-CM in the capture to Fig.1 is the mistake. M048500100055 HISTORY (19910218C) M048500100056 (20050609A) Corrected by V.Varlamov: M048500100057 Dates corrected from two to four digits including M048500100058 those in REFERENCE and HISTORY, lower case, M048500100059 volume and page numbers in REFERENCE corrected M048500100060 322,47 to 47,433. M048500100061 (20050901A) Corrected by V.Varlamov: BRA substituted M048500100062 by BRS in line REACTION of SUBENT 002. M048500100063 (20230106A) Corrected by V.Varlamov: CRITIQUE, STATUS, M048500100064 REACTION, (EN-CM) -> EN in SUBENT 002. M048500100065 ENDBIB 63 0 M048500100066 NOCOMMON 0 0 M048500100067 ENDSUBENT 66 0 M048500199999 SUBENT M0485002 20230106 20230412 M048500200001 BIB 3 5 M048500200002 REACTION (2-HE-4(G,N)2-HE-3,,SIG) M048500200003 STATUS (CURVE) Data from Fig. 1 of M048500200004 Phys.Lett.,B47(1973)433. M048500200005 HISTORY (20230106A) Corrected by V.Varlamov: REACTION, M048500200006 (EN-CM) -> EN. M048500200007 ENDBIB 5 0 M048500200008 NOCOMMON 0 0 M048500200009 DATA 3 32 M048500200010 EN DATA ERR-S M048500200011 MEV MB MB M048500200012 25. 2.05 .1 M048500200013 26. 2.07 .1 M048500200014 27. 2.06 .07 M048500200015 28. 2.01 .06 M048500200016 29. 1.95 .07 M048500200017 30. 1.84 .07 M048500200018 31. 1.7 .06 M048500200019 32. 1.6 .06 M048500200020 33. 1.49 .05 M048500200021 34. 1.37 .04 M048500200022 35. 1.29 .04 M048500200023 36. 1.21 .02 M048500200024 37. 1.11 .02 M048500200025 38. 1.08 .02 M048500200026 39. .99 .01 M048500200027 40. .92 .01 M048500200028 41. .86 .01 M048500200029 42. .8 .01 M048500200030 44. .71 .005 M048500200031 46. .63 .005 M048500200032 48. .56 .005 M048500200033 50. .5 .005 M048500200034 52. .46 .005 M048500200035 54. .42 .005 M048500200036 56. .4 .005 M048500200037 58. .36 .005 M048500200038 60. .34 .005 M048500200039 62. .31 .005 M048500200040 64. .29 .005 M048500200041 66. .29 .005 M048500200042 68. .25 .005 M048500200043 70. .22 .005 M048500200044 ENDDATA 34 0 M048500200045 ENDSUBENT 44 0 M048500299999 ENDENTRY 2 0 M048599999999