Instanton effects on electromagnetic transitions of charmonia
نویسندگان
چکیده
Abstract We investigate the mass spectrum and electromagnetic transitions of charmonia, emphasizing instanton effects on them. The heavy-quark potential consists a Coulomb-like from one-gluon exchange linear confining potential. introduce nonperturbative derived vacuum. also consider screened potential, which better describes decays higher excited states. Using this improved we compute charmonia. Focusing effects, discuss results compared with experimental data those other works. are marginal
منابع مشابه
Relativistic effects in radiative transitions of charmonia
In the framework of a relativistic quark model constructed in an infinite momentum frame, corrections of the order of v/c are obtained in the formulas which express amplitudes of the transitions ψ(ψ′) → η c (η′ c )γ, χ J → ψγ, ψ′ → χ J γ, h c → η c γ, η′ c → h c γ through overlap integrals ∫ φf(q)φi(q)dq, ∫ φf(r)rφi(r)dr. These corrections lead to a considerable suppression of Γ(ψ → η c γ), how...
متن کاملthe effects of error correction methods on pronunciation accuracy
هدف از انجام این تحقیق مشخص کردن موثرترین متد اصلاح خطا بر روی دقت آهنگ و تاکید تلفظ کلمه در زبان انگلیسی بود. این تحقیق با پیاده کردن چهار متد ارائه اصلاح خطا در چهار گروه، سه گروه آزمایشی و یک گروه تحت کنترل، انجام شد که گروه های فوق الذکر شامل دانشجویان سطح بالای متوسط کتاب اول passages بودند. گروه اول شامل 15، دوم 14، سوم 15 و آخرین 16 دانشجو بودند. دوره مربوطه به مدت 10 هفته ادامه یافت و د...
15 صفحه اولThe Dynamics of Small Instanton Phase Transitions
The small instanton transition of a five-brane colliding with one end of the S/Z2 interval in heterotic M -theory is discussed, with emphasis on the transition moduli, their potential function and the associated non-perturbative superpotential. Using numerical methods, the equations of motion of these moduli coupled to an expanding Friedmann-Robertson-Walker spacetime are solved including nonpe...
متن کاملThe effects of electromagnetic fields on fish
The objective of this paper is to survey the results of studies on the biological effects of electromagnetic fields on fish. First, the basic concepts of electromagnetism and electromagnetic spectrum and the importance of studying it in the case of fish are discussed. Then a summary of the results obtained on the effects of extremely low frequency electromagnetic fields (ELF-EMFs) and radiofreq...
متن کاملthe effects of planning on accuracy and complexity of iranian efl students’ written narrative task performance
this study compared the different effects of form-focused guided planning vs. meaning-focused guided planning on iranian pre-intermediate students’ task performance. the study lasted for three weeks and concentrated on eight english structures. forty five pre-intermediate iranian students were randomly assigned to three groups of guided planning focus-on-form group (gpfg), guided planning focus...
15 صفحه اولذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Progress of Theoretical and Experimental Physics
سال: 2022
ISSN: ['1347-4081', '0033-068X']
DOI: https://doi.org/10.1093/ptep/ptac131