Improved bounds for the slope and curvature of form factors
نویسندگان
چکیده
منابع مشابه
Improved Bounds for the Slope and Curvature of B̄ → D ( ∗ ) l ν̄ Form Factors
We derive a theoretically allowed domain for the slope ̺̂2 and curvature ĉ of the physical form factor appearing in the decay B̄ → Dl ν̄. Using heavy-quark symmetry, we relate this function to a particular B̄ → D form factor free of ground-state Bc poles below the threshold for BD production, for which almost model-independent constraints are derived from QCD using unitarity and analyticity. Our res...
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آب حاصل از بارش منبع تأمین نیازهای بی شمار جانداران به ویژه انسان است و هرگونه کاهش در کم و کیف آن مستقیماً حیات موجودات زنده را تحت تأثیر منفی قرار می دهد. نوسان سال به سال بارش از ویژگی های اساسی و بسیار مهم بارش های سالانه ایران محسوب می شود که آثار زیان بار آن در تمام عرصه های اقتصادی، اجتماعی و حتی سیاسی- امنیتی به نحوی منعکس می شود. چون میزان آب ناشی از بارش یکی از مولفه های اصلی برنامه ...
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ژورنال
عنوان ژورنال: Physics Letters B
سال: 1996
ISSN: 0370-2693
DOI: 10.1016/0370-2693(96)00509-6