ENTRY A0504 20030522 0000A050400000001 SUBENT A0504001 20030522 0000A050400100001 BIB 11 47 A050400100002 TITLE Neutron-rich heavy residues and exotic multinucleon A050400100003 transfer A050400100004 AUTHOR (Zhang Li, Zhao Jinhua, Zheng Jiwen, Wang Jicheng, A050400100005 Qin Zhi, Yang Youngfeng, Zhang Chun, Jin Genming, A050400100006 Guo Guanghui, Du Yifei, Guo Tianrui, Wang Tongqing, A050400100007 Guo Bin, Tian Jinfeng, Lou Yixiao) A050400100008 INSTITUTE (3CPRIMP) A050400100009 REFERENCE (J,PR/C,58,156,1998) A050400100010 (J,PR/C,49,592,1994) Rapid communication A050400100011 SAMPLE Molten lead was used. A050400100012 DETECTOR (HPGE) A050400100013 (BGO) To exclude 511-KeV radiation A050400100014 (SCIN) The samples were positioned in the 1.6 mm gap A050400100015 between the two 0.5-mm-thick plastic scintillators of A050400100016 the beta-ray detector. A050400100017 FACILITY (ACCEL,3CPRIMP) Heavy Ion Research Facility (HIRFL) A050400100018 METHOD (JET) The Hg-element products produced during the A050400100019 600-MeV 18-O bombardment were continuously released, A050400100020 transported, and separated by using an online A050400100021 gas-thermochromatographic device. The mercury A050400100022 isotopes, created in the inner section of the molten A050400100023 lead target material were immediately evaporated out ofA050400100024 the surface of the molten lead at a target temperature A050400100025 of ~700 C. A050400100026 The total contamination level of the separated samples A050400100027 was estimated to be less than 1%. A050400100028 (BCINT) The beam intensity was measured by a A050400100029 gas-motivation Faraday cup in front of the target A050400100030 chamber. This Faraday cup can open or shut off the A050400100031 target irradiation beam and record the instantaneous A050400100032 beam intensities at the irradiation start and end A050400100033 point. It can also periodically be inserted to monitorA050400100034 the varying beam intensities. A050400100035 (EXTB) In order to control the dead-time correction to A050400100036 a reasonable range a beam of ~2.2 particle nanoampere A050400100037 was used. A050400100038 (GSPEC) A050400100039 (BGCT) The gamma-beta coincidence measurements A050400100040 combining an anticoincident with the 511-KeV gamma raysA050400100041 detected by a large BGO detector were performed. A050400100042 ANALYSIS (AREA) A050400100043 (DECAY) A050400100044 ADD-RES The systematic of production cross section for A050400100045 different exit channels, and for different Q ground to A050400100046 ground. A050400100047 HISTORY (20030522C) A050400100048 (20030522U) Last checking has been done. A050400100049 ENDBIB 47 0 A050400100050 COMMON 1 3 A050400100051 EN A050400100052 MEV A050400100053 900. A050400100054 ENDCOMMON 3 0 A050400100055 ENDSUBENT 54 0 A050400199999 SUBENT A0504002 20030522 0000A050400200001 BIB 6 54 A050400200002 REACTION (82-PB-0(8-O-18,X)ELEM/MASS,,SIG,,TT/AV) A050400200003 The measured production cross sections for Hg isotopes A050400200004 206-Hg, 207-Hg, 208-Hg, and 209-Hg were considered as A050400200005 independent cross sections, whereas the production A050400200006 cross sections of 203-Hg and 205-Hg were classified as A050400200007 cumulative cross sections. (Comment by authors) A050400200008 DECAY-DATA ((6.)80-HG-209,35.SEC,DG,324.) A050400200009 The authors measured some gamma-rays. A050400200010 Energy (KeV) Half-life (sec) Relative intensity A050400200011 324. 35.+9-6 100. A050400200012 208.2+/-0.6 35.+13-8 51.+/-16 A050400200013 738.8+/-0.4 42.+24.-11 56.+/-20 A050400200014 1424.2+/-0.4 36.+16-8 111.+/-39 A050400200015 ((5.)80-HG-208,41.5MIN,DG,583.1,, A050400200016 DG,452.8) A050400200017 The authors measured half-life for two gamma rays. A050400200018 Energy (KeV) Half-life (min) A050400200019 452.8 41.5+5-4.1 A050400200020 583.1 40.9+11.5-7.3 A050400200021 ((4.)80-HG-207,178.SEC,DG,351.) A050400200022 Authors' result for half-life: 178.+24-19 seconds A050400200023 ((3.)80-HG-206,8.34MIN,DG,305.1) A050400200024 Authors' Result for half-life: A050400200025 8.34+1.06-0.85 min (for group A), A050400200026 8.36+0.8-0.6 min (for group B) A050400200027 COMMENT - By authors. Considering the different half-lives ofA050400200028 the neutron-rich Hg isotopes two different experimentalA050400200029 arrangements, A and B, were used. A050400200030 1. Group A: Every sample collected the separated Hg A050400200031 isotopes produced during a target irradiation duration A050400200032 of 120 sec. After shutting off the beam the sample wasA050400200033 automatically transported to a low-background A050400200034 measurement area -50 m away from the online target A050400200035 device within 15-20 sec. Then the sample was put into A050400200036 the measurement position and the detection was startedA050400200037 at, on the average, 45 sec after irradiation. The A050400200038 measurement lasted 420 sec. The data were recorded onA050400200039 time-successive multispectrum modes and the single and A050400200040 the filtered gamma-ray spectra were simultaneously A050400200041 recorded for each 20-sec time bin. A total of 143 suchA050400200042 cycles were performed. A050400200043 2. Group B: The irradiation duration is 90-100 min. A050400200044 The measurements started at 8 min after irradiation. A050400200045 The spectrum measurements lasted about 100 min. Three A050400200046 such samples were measured. Only the last sample was A050400200047 measured for 44 hours. The time bins used for A050400200048 group B were, in order, 5 min during the first hour, 20A050400200049 min during the second and third hours, and 2 hours A050400200050 during the last 40 hours. A050400200051 FLAG (1.) With the data group B. A050400200052 MISC-COL (MISC) The cross section wasconverted to 18-O+208-Pb A050400200053 system. A050400200054 ERR-ANALYS (ERR-T) The uncertainty are given in data table withoutA050400200055 any analysis. A050400200056 ENDBIB 54 0 A050400200057 COMMON 1 3 A050400200058 ELEMENT A050400200059 NO-DIM A050400200060 80. A050400200061 ENDCOMMON 3 0 A050400200062 DATA 6 7 A050400200063 MASS DATA ERR-T DECAY-FLAG FLAG MISC A050400200064 NO-DIM MICRO-B MICRO-B NO-DIM NO-DIM MICRO-B A050400200065 203. 852. 300. 1143.A050400200066 205. 253. 80. 415.A050400200067 206. 81.1 16. 3. 136.A050400200068 206. 76.2 25. 3. 1. A050400200069 207. 15.4 5. 4. 24.3A050400200070 208. 5. 1.8 5. 7.9A050400200071 209. 2.1 0.7 6. 4.A050400200072 ENDDATA 9 0 A050400200073 ENDSUBENT 72 0 A050400299999 ENDENTRY 2 0 A050499999999