ENTRY 23393 20191114 22832339300000001 SUBENT 23393001 20191114 22832339300100001 BIB 14 81 2339300100002 TITLE Measurement of the 234U(n,f) cross-section with 2339300100003 quasimonoenergetic beams in the keV and MeV range using2339300100004 a Micromegas detector assembly 2339300100005 AUTHOR (A.Stamatopoulos, A.Kanellakopoulos, A.Kalamara, 2339300100006 M.Diakaki, A.Tsinganis, M.Kokkoris, V.Michalopoulou, 2339300100007 M.Axiotis, A.Lagoyiannis, R.Vlastou) 2339300100008 INSTITUTE (2GRCTUA) A.Stamatopoulos1, A.Kanellakopoulos, 2339300100009 A.Kalamara, M.Diakaki, M.Kokkoris, V.Michalopoulou, 2339300100010 R.Vlastou 2339300100011 (2ZZZCER) M.Diakaki, A.Tsinganis 2339300100012 (2GRCATH) M.Axiotis, A.Lagoyiannis 2339300100013 REFERENCE (J,EPJ/A,54,7,2018) 2339300100014 #doi:10.1140/epja/i2018-12429-2 2339300100015 (J,EPJ/CS,146,04035,2017) prelim. data 2339300100016 FACILITY (VDGT,2GRCATH) 5.5MV Tandem Van de Graaff accelerator 2339300100017 INC-SOURCE (P-LI7) Li7(p,n)Be-7 for 450-650 keV energy range. 2339300100018 Circular LiF of ~55microg/cm2 , 2.2cm diameter, 2339300100019 made by evaporation on 500microm Ta backings. 2339300100020 (D-D) H-2(,d,n)He-3 for MeV region. 2339300100021 3.7 cm long cylindrical cell, 1 cm diameter, filled 2339300100022 with deuterium gas at 1200 mbar pressure. 2339300100023 INC-SPECT Typical flux at sample position 0.7-4. 10**5 n/cm2/sec 2339300100024 SAMPLE Uranium oxide U(3)O(8), diameter 52.00+-0.01 mm, 2339300100025 deposited on 0.1 mm Al backing via painting technique 2339300100026 at IPPE (Obninsk) and JINR (Dubna) . 2339300100027 U234 2339300100028 Specific activity, Bq/mg 2.30E+5 2339300100029 Activity on 02-01-2017, kBq 662.00+-0.08 2339300100030 Mass, mg 2.87+-0.03 2339300100031 Areal density, 10**7 nucl/cm2 3.48+-0.04 2339300100032 Impurities U232 < 10**-3 % 2339300100033 U235 2339300100034 Specific activity, Bq/mg 79.98 2339300100035 Activity on 02-01-2017, kBq 0.400+-0.006 2339300100036 Mass, mg 5.00+-0.08 2339300100037 Areal density, 10**7 nucl/cm2 6.03+-0.12 2339300100038 Impurities, % U234 <10**-3 % 2339300100039 U238 2339300100040 Specific activity, Bq/mg 12.44 2339300100041 Activity on 02-01-2017, kBq 0.122+-0.003 2339300100042 Mass, mg 9.82+-0.026 2339300100043 Areal density, 10**7 nucl/cm2 11.7+-0.4 2339300100044 Impurities, % - 2339300100045 Reference samples were U235 (keV energies and 2339300100046 background) and U238 (MeV region) . 2339300100047 DECAY-DATA (92-U-234,2.455E+5YR) 2339300100048 (92-U-235,7.04E+8YR) 2339300100049 (92-U-238,4.468E+9YR) 2339300100050 DETECTOR (SIBAR) To determine mass and impurities via alpha 2339300100051 spectroscopy. Calibrated by Am2141 source (solid angle)2339300100052 and be triple Pu240/Am241/Cm244 alpha-source * spectra)2339300100053 (DRFTC) Micromegas detector. 2339300100054 Filled with Ar:CO(2) (85:15) gas mixture at atmospheric2339300100055 chamber. 2339300100056 MONITOR (92-U-235(N,F),,SIG) For keV energy region. 2339300100057 (92-U-238(N,F),,SIG) For MeV energy region. 2339300100058 MONIT-REF (,A.D.Carlson+,J,NDS,110,3215,2009) 2339300100059 CORRECTION For the amplitude cut introduced in the analysis 2339300100060 For self-absorption of fission fragments in the sample2339300100061 For dead time - 11.9% for U234, 0.002% for U235, 2339300100062 < 0.01 % for U238. 2339300100063 For the low-energy neutrons contribution. 2339300100064 For parasitic neutron flux - f-par, f-out/in 2339300100065 En, MeV f-par f-out/in Flux,10**4 n/cm2/s2339300100066 U235 2339300100067 0.425+-0.008 0.81+-0.12 - 1.82+-0.06 2339300100068 0.550+-0.008 0.60+-0.08 - 1.75+-0.06 2339300100069 0.651+-0.008 0.77+-0.00 - 4.42+-0.18 2339300100070 U238 2339300100071 7.5+-0.1 0.036+-0.007 0.081+-0.008 7.00+-0.35 2339300100072 8.7+-0.1 0.059+-0.009 0.120+-0.007 9.51+-0.32 2339300100073 10.0+-0.1 0.18+-0.01 0.11+-0.005 20.02+-0.08 2339300100074 U234 2339300100075 0.425+-0.008 0.152+-0.003 - 2.85+-0.10 2339300100076 0.550+-0.008 0.133+-0.002 - 2.66+-0.09 2339300100077 0.651+-0.008 0.213+-0.001 - 6.93+-0.28 2339300100078 7.5+-0.1 0.029+-0.006 0.073+-0.004 14.4+-0.3 2339300100079 8.7+-0.1 0.063+-0.007 0.117+-0.001 19.4+-0.3 2339300100080 10.0+-0.1 0.242+-0.009 0.113+-0.003 40.4+-0.6 2339300100081 HISTORY (20180411C) M.M. 2339300100082 (20191114U) SD: Ref. EPJ/CS,146,04035,2017 added. 2339300100083 ENDBIB 81 0 2339300100084 NOCOMMON 0 0 2339300100085 ENDSUBENT 84 0 2339300199999 SUBENT 23393002 20180411 22692339300200001 BIB 4 15 2339300200002 REACTION (92-U-234(N,F),,SIG) 2339300200003 REL-REF (A,,D.Karadimos+,J,PR/C,89,044606,2014) 2339300200004 (A,,F.Tovesson+,J,NSE,178,57,2014) 2339300200005 (A,,C.Paradela+,J,PR/C,82,034601,2010) 2339300200006 (A,,J.W.Meadows+,J,NSE,65,171,1978) 2339300200007 (D,,G.D.James+,J,PR/C,15,2083,1977) 2339300200008 (A,,P.White+,C,65SALZBURG,1,219,1965) 2339300200009 (A,,R.W.Lamphere,J,PR,91,655,1953) 2339300200010 (A,,R.W.Lamphere,J,NP,38,561,1962) 2339300200011 A,,R.Babcock,Technical Report,Bettis Atomic Power 2339300200012 Lab.,Westinghouse, Pittsburg,PA,USA,1961 2339300200013 (A,,L.Lowry,R,LA-1714,1954) 2339300200014 Mainly agree within uncertainties 2339300200015 ERR-ANALYS (ERR-S) Statistical uncertainty 2339300200016 STATUS (TABLE) Table 4 of Europ.Phys.J. A,54,7,2018 2339300200017 ENDBIB 15 0 2339300200018 NOCOMMON 0 0 2339300200019 DATA 4 6 2339300200020 EN-MEAN EN-ERR DATA ERR-S 2339300200021 MEV MEV B B 2339300200022 0.425 0.008 0.415 0.028 2339300200023 0.550 0.008 0.871 0.050 2339300200024 0.651 0.008 0.993 0.006 2339300200025 7.5 0.1 1.90 0.04 2339300200026 8.7 0.1 2.17 0.03 2339300200027 10.0 0.1 2.13 0.04 2339300200028 ENDDATA 8 0 2339300200029 ENDSUBENT 28 0 2339300299999 ENDENTRY 2 0 2339399999999