ENTRY 22178 19910523 00002217800000001 SUBENT 22178001 19910523 00002217800100001 BIB 14 53 2217800100002 REFERENCE (J,PR/C,42,305,9007) 2217800100003 TITLE -CROSS SECTIONS OF NEON ISOTOPES INDUCED BY 5, 7, 16, 2217800100004 AND 19 MEV NEUTRONS. 2217800100005 AUTHOR (B.LAVIELLE,H.SAUVAGEON,P.BERTIN,G.HAOUAT) 2217800100006 INSTITUTE (2FR GRA) B.L., H.S., P.B. 2217800100007 (2FR BRC) G.H. 2217800100008 FACILITY (VDG,2FR BRC) 4 MV VAN DE GRAAFF ACCELERATOR, DEUTERON 2217800100009 BEAM ENERGY 1.8 - 4.0 MEV, BEAM CURRENT 15 - 25 MUA. 2217800100010 (SPECM,2FR GRA) 60 DEG AND 12 CM RADIUS MASS 2217800100011 SPECTROMETER. 2217800100012 INC-SOURCE (D-D,D-T) CYLINDRICAL GAS TARGET 100 MM LONG AND 15 MM 2217800100013 IN DIAM FILLED WITH GASEOUS 2-H OR 3-H AT A PRESSURE 2217800100014 OF 1.5 BAR. TARGET COOLED BY REFRIGERATED HE CIRCULAT-2217800100015 ING BETWEEN TWO 2.4 MICRON THICK HAVAR FOILS SEPARATED2217800100016 BY 5 MM AND ISOLATING THE NEUTRON PRODUCING TARGET 2217800100017 FROM THE EVACUATED EXTENSION. 2217800100018 EN = 5 - 7 MEV: 2-H TARGET WITH ED = 2.4 - 4 MEV 2217800100019 EN = 16 - 19 MEV: 3-H TARGET WITH ED = 1.8 - 3.2 MEV2217800100020 INC-SPECT .ENERGY RESOLUTION (+- HWHM) CALCULATED TAKING INTO 2217800100021 ACCOUNT KINEMATICS AND ENERGY LOSS AND STRAGGLING IN 2217800100022 APPARATUS. 2217800100023 SAMPLE .NATURAL MG, 99.99% PURE, IN A DISC 16.5 MM IN DIAM AND2217800100024 2 MM THICK, PLACED WITH ITS AXIS ALONG THE DEUTERON 2217800100025 BEAM AXIS AND 50 MM FROM THE END OF THE GAS TARGET 2217800100026 CYLINDER. 2217800100027 DETECTOR (TELES) 'E DELTA-E' PROTON RECOIL TELESCOPE TO MONITOR 2217800100028 NEUTRON BEAM, PLACED 100 CM FROM CENTRE OF GAS TARGET 2217800100029 AT AN ANGLE OF 20 DEG TO BEAM AXIS. ABSOLUTE CALI- 2217800100030 BRATION PERFORMED USING A SECOND SIMILAR TELESCOPE AND2217800100031 ABSOLUTE EFFICIENCY CALCULATED USING A PRECISE SIMU- 2217800100032 LATION CODE. 2217800100033 METHOD (ASEP ) MASS SPECTROMETER USED TO MEASURE NE 2217800100034 CONCENTRATIONS IN MG SAMPLES. THE SAMPLES WERE 2217800100035 OUTGASSED AT 85 DEG-C UNDER VACUUM FOR SEVERAL DAYS, 2217800100036 AND THE RELEASED NE WAS CLEANSED USING TI SPONGES, 2217800100037 HEATED CU-O-PD POWDER AND ACTIVATED CHARCOAL TRAP. 2217800100038 ABSOLUTE NEON CALIBRATION WAS OBTAINED WITH A GAS 2217800100039 PIPET OF AIR COMPOSITION. 2217800100040 CORRECTION .NEUTRON FLUENCE IS NOT CORRECTED FOR ATTENUATION AND 2217800100041 MULTIPLE NEUTRON SCATTERING IN MG SINCE THESE EFFECTS 2217800100042 ARE NEGLIGIBLE IN A 2 MM THICK SAMPLE. 2217800100043 ERR-ANALYS (ERR-T) QUADRATIC SUM OF OVERALL ERRORS IN FOLLOWING 2217800100044 QUANTITIES: 2217800100045 NO. OF MG ATOMS IN THE TARGET 2217800100046 INTEGRATED NEUTRON FLUX (INCLUDING TELESCOPE EFFI- 2217800100047 CIENCY CALIBRATION, TELESCOPE-GAS TARGET DISTANCE2217800100048 AND COUNTING STATISTICS) 2217800100049 MEASURED NE CONCENTRATIONS (INCLUDING CORRECTIONS 2217800100050 FOR CALIBRATION, TARGET/SYSTEM BLANKS, AND 2217800100051 THE CONTAMINANTS 40-AR(2+), WATER AND CO2(2+)). 2217800100052 STATUS .DATA TAKEN FROM TABLES IN MAIN REFERENCE. 2217800100053 HISTORY (910416C) S.W. 2217800100054 (910523E) 2217800100055 ENDBIB 53 0 2217800100056 NOCOMMON 0 0 2217800100057 ENDSUBENT 56 0 2217800199999 SUBENT 22178002 19910523 00002217800200001 BIB 5 10 2217800200002 REACTION (12-MG-0(N,X)10-NE-20,,SIG) 2217800200003 COMMENT .ZERO CONCENTRATIONS OF 20-NE WERE MEASURED AT THE 2217800200004 TWO LOWEST ENERGIES EN = 5.2 AND 7.0 MEV; THE 20-NE 2217800200005 PRODUCTION IS VIA 24-MG(N,N+A)20-NE WHICH HAS A 2217800200006 THRESHOLD OF 9.7 MEV. 2217800200007 CORRECTION .20-NE CONCENTRATIONS CORRECTED FOR THE INTERFERENCE 2217800200008 FROM 40-AR(2+) AND WATER CONTRIBUTIONS. 2217800200009 STATUS .DATA TAKEN FROM TABLES IN MAIN REFERENCE. 2217800200010 HISTORY (910416C) S.W. 2217800200011 (910523E) 2217800200012 ENDBIB 10 0 2217800200013 NOCOMMON 0 0 2217800200014 DATA 4 2 2217800200015 EN EN-RSL-HW DATA ERR-T 2217800200016 MEV MEV MB MB 2217800200017 16.20 0.70 115.1 8.7 2217800200018 19.05 0.35 103. 12. 2217800200019 ENDDATA 4 0 2217800200020 ENDSUBENT 19 0 2217800299999 SUBENT 22178003 19910523 00002217800300001 BIB 3 4 2217800300002 REACTION (12-MG-0(N,X)10-NE-21,,SIG) 2217800300003 STATUS .DATA TAKEN FROM TABLES IN MAIN REFERENCE. 2217800300004 HISTORY (910416C) S.W. 2217800300005 (910523E) 2217800300006 ENDBIB 4 0 2217800300007 NOCOMMON 0 0 2217800300008 DATA 4 4 2217800300009 EN EN-RSL-HW DATA ERR-T 2217800300010 MEV MEV MB MB 2217800300011 5.20 0.45 2.79 0.21 2217800300012 7.00 0.30 86.3 6.0 2217800300013 16.20 0.70 101.6 6.2 2217800300014 19.05 0.35 38.8 2.3 2217800300015 ENDDATA 6 0 2217800300016 ENDSUBENT 15 0 2217800399999 SUBENT 22178004 19910523 00002217800400001 BIB 4 12 2217800400002 REACTION (12-MG-0(N,X)10-NE-22,,SIG) 2217800400003 CORRECTION .22-NE CONCENTRATIONS CORRECTED FOR THE INTERFERENCE 2217800400004 FROM CO2(2+). THE VALUE AT EN = 19.05 MEV IS CORRECTED2217800400005 FOR THE CONTRIBUTION FROM 22-NA DECAY PRODUCED BY THE 2217800400006 REACTION 24-MG(N,T)22-NA WITH THRESHOLD 16.3 MEV. THE 2217800400007 22-NA ACTIVITY WAS TOO LOW TO BE MEASURED, SO THE 2217800400008 CORRECTION WAS MADE BY ADOPTING A VALUE OF 4.5 +- 2217800400009 1.5 MB FOR THE 22-NA PRODUCTION CROSS SECTION OF 2217800400010 NATURAL MG. 2217800400011 STATUS .DATA TAKEN FROM TABLES IN MAIN REFERENCE. 2217800400012 HISTORY (910416C) S.W. 2217800400013 (910523E) 2217800400014 ENDBIB 12 0 2217800400015 NOCOMMON 0 0 2217800400016 DATA 4 4 2217800400017 EN EN-RSL-HW DATA ERR-T 2217800400018 MEV MEV MB MB 2217800400019 5.20 0.45 5.4 1.0 2217800400020 7.00 0.30 9.48 0.91 2217800400021 16.20 0.70 11.9 1.0 2217800400022 19.05 0.35 3.8 1.7 2217800400023 ENDDATA 6 0 2217800400024 ENDSUBENT 23 0 2217800499999 SUBENT 22178005 19910523 00002217800500001 BIB 5 8 2217800500002 REACTION (12-MG-24(N,N+A)10-NE-20,,SIG) THRESHOLD 9.7 MEV 2217800500003 COMMENT .USING NATURAL ABUNDANCES OF 78.99% FOR 24-MG AND 2217800500004 10.00% FOR 25-MG. 2217800500005 CORRECTION .20-NE CONCENTRATIONS CORRECTED FOR THE INTERFERENCE 2217800500006 FROM 40-AR(2+) AND WATER CONTRIBUTIONS. 2217800500007 STATUS .DATA TAKEN FROM TABLES IN MAIN REFERENCE. 2217800500008 HISTORY (910416C) S.W. 2217800500009 (910523E) 2217800500010 ENDBIB 8 0 2217800500011 NOCOMMON 0 0 2217800500012 DATA 4 1 2217800500013 EN EN-RSL-HW DATA ERR-T 2217800500014 MEV MEV MB MB 2217800500015 16.20 0.70 146. 10. 2217800500016 ENDDATA 3 0 2217800500017 ENDSUBENT 16 0 2217800599999 SUBENT 22178006 19910523 00002217800600001 BIB 4 6 2217800600002 REACTION (12-MG-24(N,A)10-NE-21,,SIG) THRESHOLD 2.66 MEV 2217800600003 COMMENT .USING NATURAL ABUNDANCES OF 78.99% FOR 24-MG AND 2217800600004 10.00% FOR 25-MG. 2217800600005 STATUS .DATA TAKEN FROM TABLES IN MAIN REFERENCE. 2217800600006 HISTORY (910416C) S.W. 2217800600007 (910523E) 2217800600008 ENDBIB 6 0 2217800600009 NOCOMMON 0 0 2217800600010 DATA 4 2 2217800600011 EN EN-RSL-HW DATA ERR-T 2217800600012 MEV MEV MB MB 2217800600013 5.20 0.45 3.53 0.27 2217800600014 7.00 0.30 109.3 7.6 2217800600015 ENDDATA 4 0 2217800600016 ENDSUBENT 15 0 2217800699999 SUBENT 22178007 19910523 00002217800700001 BIB 5 8 2217800700002 REACTION (12-MG-25(N,A)10-NE-22,,SIG) THRESHOLD 0.5 MEV 2217800700003 COMMENT .USING NATURAL ABUNDANCES OF 78.99% FOR 24-MG AND 2217800700004 10.00% FOR 25-MG. 2217800700005 CORRECTION .22-NE CONCENTRATIONS CORRECTED FOR THE INTERFERENCE 2217800700006 FROM CO2(2+). 2217800700007 STATUS .DATA TAKEN FROM TABLES IN MAIN REFERENCE. 2217800700008 HISTORY (910416C) S.W. 2217800700009 (910523E) 2217800700010 ENDBIB 8 0 2217800700011 NOCOMMON 0 0 2217800700012 DATA 4 2 2217800700013 EN EN-RSL-HW DATA ERR-T 2217800700014 MEV MEV MB MB 2217800700015 5.20 0.45 54. 10. 2217800700016 7.00 0.30 94.8 9.1 2217800700017 ENDDATA 4 0 2217800700018 ENDSUBENT 17 0 2217800799999 ENDENTRY 7 0 2217899999999