On quark-hadron duality in the heavy quark sector

نویسنده

  • P. Colangelo
چکیده

I discuss possible failures of local quark-hadron duality in the system of heavy-light quark mesons. As an example, I consider a correlator of two currents comprising heavy quark operators, and I compare the OPE expression with the result obtained by a complete insertion of hadronic states. After a smearing procedure, OPE and hadronic spectral functions agree with each other. However, the local behaviour of the two functions is different, and the difference manifests itself in a term which is absent in the OPE.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Se p 20 00 SPECTATOR EFFECTS AND QUARK - HADRON DUALITY IN INCLUSIVE BEAUTY DECAYS

5 Quark-hadron duality 51 6 Conclusion 55 ii 0.1 Preface This Thesis is a review of the inclusive decays of heavy hadron. It is based on the author's study of two issues which are important in the description of the inclusive beauty decays given by the heavy quark expansion. • Evaluation of the expectation values of the four-quark operators in the heavy quark expansion, • Study on the validity ...

متن کامل

Explicit Quark - hadron Duality in Heavy - light Meson Weak Decays in the ’ t Hooft Model

We compute the nonleptonic weak decay width of a heavy-light meson in 1+1 spacetime dimensions with a large number of QCD colors (the ’t Hooft model) as a function of the heavy quark mass. In this limit, QCD is exactly soluble, and decay modes are dominated by two-particle final states. We compare the results to the tree-level partonic decay width of the heavy quark in order to test quark-hadro...

متن کامل

THE ROLE OF QUARK POLARIZATION IN HEAVY QUARK FRAGMENTATION

We calculate the exact fragmentation functions for c and b quark fragmentation taking into account the spin orientation of the initial heavy quark in the form of analytical and rather simple expressions. Our calculations show that spin orientation may have an important effect on the fragmentation spectrum. This effect is more striking in the cases of c ?D, D*; c? ? , ? , and ?B , B *.

متن کامل

Quark-hadron-duality in the charmonium and upsilon system

In this work we discuss the practical and conceptual issues related to quark-hadron-duality in heavy-heavy systems. Recent measurements in the charmonium region allow a direct test of quark-hadronduality. We present a formula for non-resonant background production in e+e− → DD and extract the resonance parameters of the ψ(3S) − ψ(6S). The obtained results are used to investigate the upsilon ene...

متن کامل

A note on spectator effects and quark-hadron duality in inclusive beauty decays

In this paper, we evaluate the expectation values of four-quark operators for the inclusive beauty decays from the differences in the inclusive total decay rates, assuming that the heavy quark expansion converges at O(1/m). The obtained expectation values values yeilds the ratio τ(Λb)/τ(B) close to the experimental value. We further point out that the quark-hadron duality violation would be rat...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 1997