[題目] 同位旋問題和態的運算

看板Physics作者 (小甜心)時間16年前 (2008/05/05 21:41), 編輯推噓0(004)
留言4則, 2人參與, 最新討論串1/1
[領域] 近代物理 (題目相關領域) [來源] 參考書編輯為考古題 (課本習題、考古題、參考書...) [題目] Isospin is a symmetry introduced by Heisnberg to explain some properties of nuclear interactions involving proton(p), neutron(n), and pion(π). Proton is assigned to have isospin l=1/2 with the z-component l_z=1/2(i.e |1/2,1/2> or isospin up state);neutron is assigned to the |1/2,-1/2> state. What will be the possible isospin state for deuteron? You can copy the idea for the addition of the angular momentum here to the case of isospin since they behave the same mathematically. If you know that Δ^+ is assigned to the isospin |3/2,1/2> state and Δ^+ can decay either to pπ^0 or to nπ^+ ,what will be the decay percentage for each mode assuming isospin is a good symmetry? Note that π^+ is an isospin |1,1> state , and π^0 is |1,0> state; the ladder operator for spin has the following relationship in Natural unit: S |sm>=√([s(s+1)-m(m+1) ] )|s(m-1)> [瓶頸] 對態的運算有困難 請各位幫忙 (寫寫自己的想法,方便大家為你解答) -- 當我說我希望保存美麗而以死亡暫停住時間,你卻跟我說那是扼殺 不過看見時光的逝去比死亡更痛苦啊 這是部落格 http://0rz.tw/763xV -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 218.166.62.132

05/06 00:55, , 1F
以前有回答過類似的問題,請參考8246的文章
05/06 00:55, 1F

05/06 19:13, , 2F
我覺得這題最難的是從那個公式算CG係數...
05/06 19:13, 2F

05/06 19:13, , 3F
我看書上的通用公式都長到記不起來
05/06 19:13, 3F

05/06 19:14, , 4F
雖然這題算好推的了
05/06 19:14, 4F
文章代碼(AID): #187mwH59 (Physics)