ENTRY C2526 20200422 C195C252600000001 SUBENT C2526001 20200422 C195C252600100001 BIB 11 44 C252600100002 TITLE Low-Energy Gamma Radiation from the Bombardment of C252600100003 Carbon by Protons C252600100004 AUTHOR (H.H.Woodbury,A.V.Tollestrup,R.B.Day) C252600100005 REFERENCE (J,PR,93,1311,1954) C252600100006 #doi:10.1103/PhysRev.93.1311 C252600100007 REL-REF (I,C1647001,H.H.Woodbury+,J,PR,92,1199,1953) The C252600100008 counter and associated electronic equipment. C252600100009 INSTITUTE (1USACAL) C252600100010 FACILITY (VDG,1USACAL) California Institute of Technology 3-MeV C252600100011 electrostatic accelerator. C252600100012 SAMPLE Two types of targets were used. One was prepared by C252600100013 holding cleaned tantalum over a smoky benzene flame; C252600100014 the second was prepared by cracking methane C252600100015 (natural gas) on a hot strip of tantalum for the C252600100016 preparation of C13 targets. The target thickness was C252600100017 found by measuring the width of the 1.76-MeV C252600100018 resonance in C13(p,gamma)N13. This resonance is C252600100019 strong enough to be easily observable in normal C252600100020 carbon, and since it has a width of only 2 keV, while C252600100021 the targets were 20 to 100 keV thick, the observed C252600100022 resonance width was equal to the target thickness. C252600100023 Knowing the target thickness in keV, one could then C252600100024 calculate the number of carbon atoms per square C252600100025 centimeter by dividing by the stopping cross section C252600100026 of carbon at the average proton bombarding energy C252600100027 used in determining the target thickness. C252600100028 DETECTOR (NAICR) The scintillation spectrometer consisted of C252600100029 an Nal(T1) crystal 1.5, inches long and 1.5, inches C252600100030 in diameter mounted on a 5819 photomultiplier. C252600100031 METHOD (PHWT) Since the background radiation from the C252600100032 electrostatic accelerator and from other reactions in C252600100033 the target was generally very much more intense than C252600100034 the gamma ray of interest here, it was necessary to C252600100035 identify the latter by means of its characteristic C252600100036 photopeak produced in the NaI(Tl) scintillation C252600100037 counter. Therefore, the measurements required a C252600100038 pulse-height spectrum to be obtained at each C252600100039 bombarding energy. C252600100040 CORRECTION To obtain the true yields it was also necessary to C252600100041 make a correction for absorption of the gamma rays in C252600100042 the target chamber. This was only 2 to 4 percent for C252600100043 the measurements at 90 degree, but amounted to C252600100044 approximately 20 percent at O degree. C252600100045 HISTORY (20200422C) BP C252600100046 ENDBIB 44 0 C252600100047 NOCOMMON 0 0 C252600100048 ENDSUBENT 47 0 C252600199999 SUBENT C2526002 20200422 C195C252600200001 BIB 3 3 C252600200002 REACTION (6-C-12(P,G)7-N-13,PAR,DA) C252600200003 SAMPLE First target type. C252600200004 STATUS (CURVE) Fig. 5, page 1313. Circles experiment. C252600200005 ENDBIB 3 0 C252600200006 COMMON 2 3 C252600200007 ANG E-LVL C252600200008 ADEG MEV C252600200009 0.0 2.369 C252600200010 ENDCOMMON 3 0 C252600200011 DATA 2 7 C252600200012 EN DATA C252600200013 MEV B/SR C252600200014 1.497 0.282E-07 C252600200015 1.594 0.347E-07 C252600200016 1.647 0.606E-07 C252600200017 1.695 0.778E-07 C252600200018 1.712 0.713E-07 C252600200019 1.755 0.313E-07 C252600200020 1.798 0.226E-07 C252600200021 ENDDATA 9 0 C252600200022 ENDSUBENT 21 0 C252600299999 SUBENT C2526003 20200422 C195C252600300001 BIB 3 3 C252600300002 REACTION (6-C-12(P,G)7-N-13,PAR,DA) C252600300003 SAMPLE Second target type. C252600300004 STATUS (CURVE) Fig. 5, page 1313. Squares experiment. C252600300005 ENDBIB 3 0 C252600300006 COMMON 2 3 C252600300007 ANG E-LVL C252600300008 ADEG MEV C252600300009 0.0 2.369 C252600300010 ENDCOMMON 3 0 C252600300011 DATA 2 11 C252600300012 EN DATA C252600300013 MEV B/SR C252600300014 1.357 0.283E-07 C252600300015 1.538 0.293E-07 C252600300016 1.617 0.346E-07 C252600300017 1.632 0.682E-07 C252600300018 1.665 0.995E-07 C252600300019 1.669 1.298E-07 C252600300020 1.718 0.703E-07 C252600300021 1.723 0.973E-07 C252600300022 1.755 0.324E-07 C252600300023 1.869 0.236E-07 C252600300024 1.967 0.247E-07 C252600300025 ENDDATA 13 0 C252600300026 ENDSUBENT 25 0 C252600399999 SUBENT C2526004 20200422 C195C252600400001 BIB 3 3 C252600400002 REACTION (6-C-12(P,G)7-N-13,PAR,DA) C252600400003 SAMPLE First target type. C252600400004 STATUS (CURVE) Fig. 5, page 1313. Circles experiment. C252600400005 ENDBIB 3 0 C252600400006 COMMON 2 3 C252600400007 ANG E-LVL C252600400008 ADEG MEV C252600400009 90.0 2.369 C252600400010 ENDCOMMON 3 0 C252600400011 DATA 2 14 C252600400012 EN DATA C252600400013 MEV B/SR C252600400014 1.405 2.166E-07 C252600400015 1.573 3.142E-07 C252600400016 1.622 3.260E-07 C252600400017 1.631 3.389E-07 C252600400018 1.652 3.807E-07 C252600400019 1.704 1.877E-07 C252600400020 1.725 0.912E-07 C252600400021 1.751 0.879E-07 C252600400022 1.774 1.298E-07 C252600400023 1.790 1.480E-07 C252600400024 1.995 2.509E-07 C252600400025 2.184 2.724E-07 C252600400026 2.382 2.306E-07 C252600400027 2.588 2.456E-07 C252600400028 ENDDATA 16 0 C252600400029 ENDSUBENT 28 0 C252600499999 SUBENT C2526005 20200422 C195C252600500001 BIB 3 3 C252600500002 REACTION (6-C-12(P,G)7-N-13,PAR,DA) C252600500003 SAMPLE Third target type. C252600500004 STATUS (CURVE) Fig. 5, page 1313. Cross experiment. C252600500005 ENDBIB 3 0 C252600500006 COMMON 2 3 C252600500007 ANG E-LVL C252600500008 ADEG MEV C252600500009 90.0 2.369 C252600500010 ENDCOMMON 3 0 C252600500011 DATA 2 8 C252600500012 EN DATA C252600500013 MEV B/SR C252600500014 1.279 2.102E-07 C252600500015 1.378 2.745E-07 C252600500016 1.476 2.885E-07 C252600500017 1.523 2.777E-07 C252600500018 1.616 3.142E-07 C252600500019 1.706 1.641E-07 C252600500020 1.809 1.458E-07 C252600500021 1.882 2.477E-07 C252600500022 ENDDATA 10 0 C252600500023 ENDSUBENT 22 0 C252600599999 SUBENT C2526006 20200422 C195C252600600001 BIB 3 3 C252600600002 REACTION (6-C-12(P,G)7-N-13,PAR,DA) C252600600003 SAMPLE Second target type. C252600600004 STATUS (CURVE) Fig. 5, page 1313. Squares experiment. C252600600005 ENDBIB 3 0 C252600600006 COMMON 2 3 C252600600007 ANG E-LVL C252600600008 ADEG MEV C252600600009 90.0 2.369 C252600600010 ENDCOMMON 3 0 C252600600011 DATA 2 14 C252600600012 EN DATA C252600600013 MEV B/SR C252600600014 1.187 1.394E-07 C252600600015 1.255 1.909E-07 C252600600016 1.341 1.802E-07 C252600600017 1.403 2.166E-07 C252600600018 1.489 2.509E-07 C252600600019 1.635 3.657E-07 C252600600020 1.682 2.005E-07 C252600600021 1.869 2.038E-07 C252600600022 1.955 2.370E-07 C252600600023 2.163 2.424E-07 C252600600024 2.568 2.316E-07 C252600600025 2.669 2.595E-07 C252600600026 2.798 2.724E-07 C252600600027 2.888 2.338E-07 C252600600028 ENDDATA 16 0 C252600600029 ENDSUBENT 28 0 C252600699999 SUBENT C2526007 20200422 C195C252600700001 BIB 3 3 C252600700002 REACTION (6-C-12(P,G)7-N-13,PAR,DA) C252600700003 SAMPLE Fourth target type. C252600700004 STATUS (CURVE) Fig. 5, page 1313. Triangle experiment. C252600700005 ENDBIB 3 0 C252600700006 COMMON 2 3 C252600700007 ANG E-LVL C252600700008 ADEG MEV C252600700009 90.0 2.369 C252600700010 ENDCOMMON 3 0 C252600700011 DATA 2 10 C252600700012 EN DATA C252600700013 MEV B/SR C252600700014 1.268 1.823E-07 C252600700015 1.476 2.113E-07 C252600700016 1.504 2.681E-07 C252600700017 1.656 3.067E-07 C252600700018 1.811 1.855E-07 C252600700019 1.841 2.102E-07 C252600700020 1.858 1.737E-07 C252600700021 1.892 2.188E-07 C252600700022 2.088 2.842E-07 C252600700023 2.388 3.206E-07 C252600700024 ENDDATA 12 0 C252600700025 ENDSUBENT 24 0 C252600799999 ENDENTRY 7 0 C252699999999