Radiochemical Study on Photonuclear Reactions at Intermediate Energies

中能光核反应的放射化学研究

• 批准号: 01470049
• 负责人: SAKAMOTO Koh
• 金额: $ 4.16万
• 依托单位: Kanazawa University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1989
• 资助国家: 日本
• 起止时间: 1989 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-01470049/
• 关键词: Intermediate Energy; Photopion; Photospallation; Photofragmentation; PICA; Rudstam formula; ^7Li-^<209>Bi; Cross Sections; 光核反応生成核収率; 光子誘導カスケ-ド蒸発モデル計算; モニタ-反応; π^±中間子放出反応; 核破砕; フラグメンテ-ション; 加速器質量分析; γ線スペクトロメトリ-

A systematic radiochemical study on bremsstrahlung-induced photopion, photospallation and photofragmentation was performed on targets ranging from ^7Li to ^<207>Bi at end-point energies (E_0) from 40 to 1000 MeV in steps of 100 MeV or less.(1) The yields of ^7Be, ^<11>C, ^<27>Mg, ^<41>Ar, ^<59>Fe, ^<87>Kr, ^<88>Rb, ^<103>Ru, ^<133>Xe, ^<139>Ba and ^<181>Hf from (gamma, pi^<<plus-minus>>) reaction and of ^<59-x>Ni(x=2,3), ^<127-x>Xe(x=0-6), ^<133-x>Ba(x=0-9), ^<139-x>Ce (x=0-8) from (gamma, pi ^-xn reactions were obtained from ^7Li, ^<11>B, ^<27>Al, ^<41>K, ^<59>Co, ^<87>Rb, ^<88>Sr, ^<103>Rh, ^<127>I, ^<133>Cs, ^<139>La and ^<181>Ta. Unfolding into cross sections per photon of monochromatic energy k was performed on the measured yields after correction for secondary reactions. Excitation curves were characteristic of (3,3) resonance, and their systematic features with respect of k (and E_0), A_t and x were derived and discussed with references of total photoabsorption cross sections an … More d also of PICA (photon-induced cascade analysis) calculations. Results were consistent with our previous findings from ^<51>V (gamma, pi^+) ^<51>Ti, ^<51>V (gamma, pi^-xn) ^<51-x>Cr (x=0,2,3), ^<89>Y (gamma, pi^-xn) ^<89-x>Zr (x=0-3), ^<197>Au (gamma, pi^-xn) ^<197-x>Hg (x=0-7) and ^<209>Bi (gamma, pi^-xn) ^<209-x>Po (x=2-7).(2) The measured yields of 21 to 47 products ranging in 5-10 elements each from the targets of ^<51>V, ^<59>Co, ^<89>Y, ^<127>I, ^<133>Cs, ^<139>La, ^<176>Lu, ^<197>Au and ^<209>Bi were measured as a function of E_0 from thresholds to 1000 MeV. After correction for precursor-decays, isotopic, isobaric and charge distributions and their E_0 and A_t dependences were investigated and a new empirical expression for the product formations were proposed with reference to Rudstam formula for hadron spallation. PICA calculations for bremsstrahlung spallation were performed and found not to reproduce the observed yields especially for medium to heavy targets.(3) While the ^<22.24>Na yields from ^<35.37>Cl, ^<63.67>Cu and ^<89>Y were explained by spallation, photofragmentaion was evidenced with high but mass dependent yields of ^<7.10>Be from these targets. Less

本文<207>以100 MeV或更小的能量步长，在40 ~ 1000 MeV的端点能量（E_0）范围内，对从^7 Li到^7 Bi的靶进行了韧致电离、光致电离和光致碎裂的系统放射化学研究。(1)由~ 7 Li、~ B、~ 4Al、~ 4K、~ 4Co、~ 4 Rb、~ 4Sr、~ <11>4 Rh、~ 4 I、~ 4Cs、~ 4La和~ 4 Ta得到~ 7 Be、~ 4C、~ 4 <27>Mg、~ 4Ar、~ <41>4Fe、~ <59>4Kr<87><88>、~ 4 Rb、~ 4 <103>Ru<133>、~ 4 <139>Ba、~ 4 <181>Hf和~ <plus-minus>4 <59-x>Ni（x= 2，3）<127-x>、~ 4 Ba（x =0-6）、~ 4 <133-x>Ba（x =0-9）、~ <139-x>4Ce（x=0-8）<11><27><41><59><87><88><103><127><133><139>的产率<181>。展开为单色能量k的每个光子的横截面，在校正二次反应后对测量的产率进行。激发曲线具有（3，3）共振的特征，导出了它们随k（和E_0）、A_t和x的系统特征，并结合总光吸收截面和 ...更多信息 d也是PICA（光子诱导级联分析）计算。结果与我们先前从^<51>V（γ，π ^+）^<51>Ti、^<51>V（γ，π ^-xn）^<51-x>Cr（x= 0，2，3）、^<89>Y（γ，π ^-xn）^<89-x>Zr（x=0-3）、^<197>Au（γ，π ^-xn）^<197-x>Hg（x=0-7）和^<209>Bi（γ，π ^-xn）^<209-x>Po（x=2-7）的发现一致。(2)在阈至1000 MeV范围内，测量了靶中~ <51>V、~ <59>Co、~ <89>Y、~ <127>I、~ <133>Cs、~ <139>La、~ <176>Lu、~ <197>Au和~ <209>Bi的21 ~ 47个产物的产额，每个产物中含有5-10个元素。在对强子衰变进行修正后，研究了同位素、等压和电荷分布及其与E_0和A_t的关系，并参照Ruddron强子谱公式，提出了一个新的产物生成经验表达式。进行韧致辐射的PICA计算，发现不能再现观察到的产率，特别是对于中到重的目标。(3)虽然<22.24>^<35.37>Cl、^<63.67>Cu和^<89>Y的^ Na产率可以通过散裂来解释，但这些靶的^ Be产率很高，但取决于质量，这证明了光致碎裂<7.10>。少

项目成果

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S.R.Sarkar 等人：“中能复杂原子核的光散裂”Radiochim.Acta, (1991)

S. R. Sarkar, Y. Kubota, T. Fukasawa, K. Kawaguchi, K. Sakamoto, S. Shibata and I. Fujiwara :"Photospallation of Complex Nuclei at Intermediate Energies-II." Radiochim. Acta,. (1991)

S. R. Sarkar、Y. Kubota、T. Fukasawa、K. Kawaguchi、K. Sakamoto、S. Shibata 和 I. Fujiwara：“中能复杂原子核的光散裂-II”。

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K. Sakamoto、Y. Hamajima、M. Soto、Y. Kubota、M. Yoshida、A. Kunugise、M. Masatani、S. Shibata、M. Imamura 和 I. Fujiwata：“光π离子反应中的钡和氙同位素产率

K.Sakamoto,et al.: "Barium and Xenon Isotope Yields in Photopion Reactions of ^<133>Cs" Phys.Rev.C,. 42. 1545-1558 (1990)

K.Sakamoto 等人：“^<133>Cs 光π反应中的钡和氙同位素产量”Phys.Rev.C,。