ENTRY L0275 20250206 L055L027500000001 SUBENT L0275001 20250206 L055L027500100001 BIB 13 49 L027500100002 TITLE Exploratory study of the 180mTa(gamma,gamma')180Ta L027500100003 reaction with mono-energetic low-energy photon beams L027500100004 at HIgS L027500100005 AUTHOR (W.Tornow,M.Bhike,S.W.Finch,Krishichayan) L027500100006 REFERENCE (J,NIM/A,928,79,2019) L027500100007 #doi:10.1016/j.nima.2019.03.036 L027500100008 INSTITUTE (1USADKE,1USATNL) L027500100009 FACILITY (ESTRG,1USATNL) The High-Intensity Gamma-ray Source L027500100010 (HIgS) at Triangle Universities Nuclear Laboratory L027500100011 (TUNL). L027500100012 INC-SOURCE (LCS) L027500100013 DETECTOR (HPGE) L027500100014 SAMPLE Natural tantalum targets of 2.54 cm diameter and 0.12 L027500100015 mm thickness with mass of 1.2 g containing only 140 L027500100016 microg of 180mTa. L027500100017 METHOD (ACTIV) De-excitation cross section of the isomeric- L027500100018 state nuclide 180mTa has been measured with L027500100019 mono-energetic photon beams in the 1.56 MeV to 3.70 L027500100020 MeV energy range. After irradiation for typically 20 L027500100021 h with photon fluxes ranging from 0.3*10**7 L027500100022 gamma/(cm2*s) to 3.2*10**7 gamma/(cm2*s), the 180mTa L027500100023 de-excitation cross section was obtained from the L027500100024 yield of the Kalpha1 and Kalpha2 X rays of 180mHf at L027500100025 55.79 keV and 54.61 keV, respectively, produced after L027500100026 electron capture on the unstable 180mTa ground state. L027500100027 The tantalum disks were gamma-ray counted with a L027500100028 planar HPGe detector. For this purpose the disk was L027500100029 attached directly to the front face of the 30 mm L027500100030 diameter detector. Its efficiency was measured in the L027500100031 region of interest with a calibrated multi-isotope L027500100032 gamma-ray source, including 241Am with X rays at L027500100033 59.54 keV. L027500100034 ERR-ANALYS (ERR-T) The uncertainty assigned to the data include L027500100035 the statistical uncertainties plus an estimated 25% L027500100036 uncertainty in bremsstrahlung correction, except at L027500100037 Egamma=1.8 MeV, where a 18% uncertainty was used. L027500100038 The latter two uncertainties are estimates based on L027500100039 the present single-electron and two-electron bunch L027500100040 tests and past experience. All individual L027500100041 uncertainties were added in quadrature. L027500100042 (ERR-1,18.,25.) Bremsstrahlung correction. L027500100043 CORRECTION A sizable attenuation correction of 1.3 had to be L027500100044 applied, using the X-ray attenuation factor. A small L027500100045 correction was applied to account for the slightly L027500100046 different electron beam currents used at some of the L027500100047 energies. The bremsstrahlung correction. L027500100048 DECAY-DATA (73-TA-180-G,8.154HR,XR,55.79,0.35) Kalpha1 L027500100049 (73-TA-180-G,8.154HR,XR,54.61,0.203) Kalpha2 L027500100050 HISTORY (20250206C) BP L027500100051 ENDBIB 49 0 L027500100052 NOCOMMON 0 0 L027500100053 ENDSUBENT 52 0 L027500199999 SUBENT L0275002 20250206 L055L027500200001 BIB 2 2 L027500200002 REACTION (73-TA-180-M(G,INL)73-TA-180-G,,SIG) L027500200003 STATUS (TABLE,,W.Tornow+,J,NIM/A,928,79,2019) Table 1 L027500200004 ENDBIB 2 0 L027500200005 NOCOMMON 0 0 L027500200006 DATA 4 8 L027500200007 EN EN-RSL DATA ERR-T L027500200008 MEV MEV MB MB L027500200009 1.56 0.03 4.0 1.4 L027500200010 1.80 0.03 4.0 0.9 L027500200011 2.04 0.04 2.1 0.7 L027500200012 2.33 0.04 4.7 1.5 L027500200013 2.59 0.05 3.4 1.1 L027500200014 2.80 0.06 2.0 0.7 L027500200015 3.60 0.07 4.3 1.4 L027500200016 3.70 0.07 4.7 1.5 L027500200017 ENDDATA 10 0 L027500200018 ENDSUBENT 17 0 L027500299999 ENDENTRY 2 0 L027599999999