Modified contour-improved perturbation theory

نویسندگان
چکیده

برای دانلود باید عضویت طلایی داشته باشید

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

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Renormalization-Group-improved perturbation theory

A method for computing the low-energy non-perturbative properties of SUSY GFT, starting from the microscopic lagrangian model, is presented. The method relies on covariant SUSY Feynman graph techniques, adapted to low energy, and RenormalizationGroup-improved perturbation theory. We apply the method to calculate the glueball superpotential in N = 1 SU(2) SYM and obtain a potential of the Venezi...

متن کامل

Contour-improved versus fixed-order perturbation theory in hadronic τ decays

The hadronic decay rate of the τ lepton serves as one of the most precise determinations of the QCD coupling αs. The dominant theoretical source of uncertainty at present resides in the seeming disparity of two approaches to improving the perturbative expansion with the help of the renormalisation group, namely fixed-order and contourimproved perturbation theory. In this work it is demonstrated...

متن کامل

αs and the τ hadronic width: fixed-order, contour- improved and higher-order perturbation theory

The determination of αs from hadronic τ decays is revisited, with a special emphasis on the question of higher-order perturbative corrections and different possibilities of resumming the perturbative series with the renormalisation group: fixed-order (FOPT) vs. contour-improved perturbation theory (CIPT). The difference between these approaches has evolved into a systematic effect that does not...

متن کامل

On the determination of αs from hadronic τ decays with contour-improved, fixed order and renormalon-chain perturbation theory

One of the largest theoretical uncertainties assigned to the strong coupling constant αs as determined from hadronic tau decays stems from the differences in the results for Fixed Order Perturbation Theory (FOPT), Contour Improved Perturbation Theory (CIPT) and Renormalon Chain Perturbation Theory (RCPT). It is often argued that the three methods differ in the treatment of higher orders only an...

متن کامل

The asymmetric single - impurity Anderson model – the modified perturbation theory

——————————————————————————————————————— Abstract We investigate the single-impurity Anderson model by means of the recently introduced modified perturbation theory. This approximation scheme yields reasonable results away from the symmetric case. The agreement with exactly known results for the symmetric case is checked, and results for the non-symmetric case are presented. With decreasing cond...

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

ژورنال

عنوان ژورنال: Physical Review D

سال: 2010

ISSN: 1550-7998,1550-2368

DOI: 10.1103/physrevd.82.093007