ENTRY 23200 20131022 22372320000000001 SUBENT 23200001 20131022 22372320000100001 BIB 16 55 2320000100002 REFERENCE (J,NIM/A,727,1,2013) 2320000100003 AUTHOR (J.Praena, P.F.Mastinu, M.Pignatari, J.M.Quesada, 2320000100004 J.Garcia-Lopez, M.Lozano, N.Dzysiuk, R.Capote, 2320000100005 G.Martin-Hernandez) 2320000100006 TITLE Measurement of the MACS of Ta-181(n,gamma) at kT=30 keV2320000100007 as a test of a method for Maxwellian neutron spectra 2320000100008 generation. 2320000100009 INSTITUTE (2SPNSEU) J.Praena,J.M.Quesada,J.Garcia-Lopez,M.Lozano.2320000100010 Centro Nacional de Aceleradores (CNA), 2320000100011 Sevilla,Spain, http://centro.us.es/cna/ 2320000100012 J.Praena, J.Garcia-Lopez. 2320000100013 (2ITYPAD) P.F.Mastinu 2320000100014 (2SWTBAS) M.Pignatari. 2320000100015 (4UKRUKR) Intern. Nuclear Safety Center of Ukraine, 2320000100016 Kyiv, Ukraine. http://www.insc.gov.ua/ 2320000100017 N.Dzysiuk. 2320000100018 (3ZZZIAE) R.Capote 2320000100019 (3CUBPLY) Centro de Aplicaciones Tecnologicas y 2320000100020 Desarrollo Nuclear, 5ta y 30, Playa, La Havana,Cuba. 2320000100021 http://www.ceaden.cu/ 2320000100022 G.Martin-Hernandez. 2320000100023 REL-REF (I,,P.F.Mastinu+,J,NIM/A,601,333,2009) 2320000100024 Details of setup. 2320000100025 FACILITY (VDGT) 3 MV Tandem Pelletron Accelerator at CNA. 2320000100026 INC-SOURCE (P-LI7) Li layer of 390 microm thickness, water cooled.2320000100027 Proton beam current 3 microA . 2320000100028 Terminal voltage 1.789 MV (equivalent to proton 2320000100029 energy 3.665 MeV) was found to be optimal to produce 2320000100030 INC-SPECT Maxwellian neutron spectrum with kT=30 keV. 2320000100031 Neutron spectra were obtained by combining analytical 2320000100032 description of Li7(n,P) reaction energy-angular 2320000100033 distribution and Monte Carlo simulation ( MCNPX code) 2320000100034 of the neutron transport within exp.setup. 2320000100035 SAMPLE Gold and tantalum samples of 2.5 cm diameter, 0.1 mm 2320000100036 and 0.75 mm thickness, respectively, were secured to 2320000100037 the back surface of the backings. 2320000100038 METHOD (ACTIV) 3hr neutron irradiation. 2320000100039 DETECTOR (HPGE) HPGe from ORTEC (GMX Serie). 2320000100040 MONITOR (79-AU-197(N,G)79-AU-198,,SIG,,MXW) 2320000100041 MACS for Au was used as reference. 2320000100042 DECAY-MON (79-AU-198-G,2.6947D,DG,411.8,0.956) 2320000100043 MONIT-REF (22099001,W.Ratynski+,J,PR/C,37,595,1988) 2320000100044 CORRECTION -For self-absorption and multiple scattering for Au 2320000100045 correction coefficient 0.988. 2320000100046 -For self-absorption and multiple scattering for Ta 2320000100047 correction coefficient 0.975. 2320000100048 -Fluence ratio gold/tantalum was estimated to be 1.03 2320000100049 assuming an average of 92.5% for the tantalum flux 2320000100050 reduction. 2320000100051 - Environmental background was measured. 2320000100052 - Efficiency was corrected considering the solid angle 2320000100053 covered by Ta and Au sample. 2320000100054 - Dead time < 0.2 %, negligible. 2320000100055 - Proton beam instability was small and negligible. 2320000100056 HISTORY (20131022C) M.M. 2320000100057 ENDBIB 55 0 2320000100058 NOCOMMON 0 0 2320000100059 ENDSUBENT 58 0 2320000199999 SUBENT 23200002 20131022 22372320000200001 BIB 4 19 2320000200002 REACTION (73-TA-181(N,G)73-TA-182,,SIG,,MXW) 2320000200003 DECAY-DATA (73-TA-182-G,114.7D,DG,1121.3,0.352) 2320000200004 ERR-ANALYS Uncertainties (one sigma) were taken into account: 2320000200005 (ERR-1) Thickness of samples. 2320000200006 (ERR-2) Correction for self-absorption and multiple 2320000200007 scattering for Au. 2320000200008 (ERR-3) Correction for self-absorption and multiple 2320000200009 scattering for Ta. 2320000200010 (ERR-4,,0.2) Uncertainty of Au gamma-line intensity. 2320000200011 (ERR-5,,0.2) Uncertainty of Ta gamma-line intensity. 2320000200012 (ERR-6) Detection efficiency. 2320000200013 (ERR-7,,0.1) Au half-life. 2320000200014 (ERR-8) Ta half-life. 2320000200015 (ERR-9) Fluence ratio gold/tantalum. 2320000200016 (ERR-10) Fitting procedure. 2320000200017 (MONIT-ERR) MACS Au reference. 2320000200018 (ERR-S) Counting statistics. 2320000200019 (ERR-T) Total uncertainty 9 %. 2320000200020 STATUS (TABLE) Table 2 of J,NIM/A,727,1,2013 2320000200021 ENDBIB 19 0 2320000200022 COMMON 8 6 2320000200023 ERR-1 ERR-S ERR-2 ERR-3 ERR-6 ERR-8 2320000200024 ERR-9 ERR-10 2320000200025 PER-CENT PER-CENT PER-CENT PER-CENT PER-CENT PER-CENT 2320000200026 PER-CENT PER-CENT 2320000200027 0.1 0.3 0.2 0.4 5.8 0.1 2320000200028 0.2 0.1 2320000200029 ENDCOMMON 6 0 2320000200030 DATA 5 1 2320000200031 KT DATA ERR-T MONIT MONIT-ERR 2320000200032 KEV MB MB MB PER-CENT 2320000200033 30. 815. 73. 582. 1.5 2320000200034 ENDDATA 3 0 2320000200035 ENDSUBENT 34 0 2320000299999 ENDENTRY 2 0 2320099999999