English
Related papers

Related papers: Order $\alpha_s(Q^2)$ QCD corrections to the polar…

200 papers

We demonstrate that spontaneous transverse polarization of Lambda baryon ($\Lambda$) production in $e^+e^-$ annihilation can be described using the transverse momentum dependent polarizing fragmentation functions (TMD PFFs). Using a simple…

High Energy Physics - Phenomenology · Physics 2020-11-18 Daniel Callos , Zhong-Bo Kang , John Terry

A QCD analysis of the world data on polarized deep inelastic scattering is presented in next--to--leading order, including the heavy flavor Wilson coefficient in leading order in the fixed flavor number scheme. New parameterizations are…

High Energy Physics - Phenomenology · Physics 2014-11-21 Johannes Blümlein , Helmut Böttcher

The results of a recent next-to-leading order QCD analysis of the world data on polarized deep inelastic scattering are reported. New parameterizations are derived for the quark and gluon distributions, accounting for the massive Wilson…

High Energy Physics - Phenomenology · Physics 2015-05-20 Johannes Blümlein , Helmut Böttcher

We present a first analysis of parton-to-pion fragmentation functions at next-to-next-to-leading order accuracy in QCD based on single-inclusive pion production in electron-positron annihilation. Special emphasis is put on the technical…

High Energy Physics - Phenomenology · Physics 2016-04-11 Daniele P. Anderle , Felix Ringer , Marco Stratmann

We study the production of polarized $\Lambda$-hyperons in electron-positron annihilation. We are particularly interested in the transverse-spin dependence of the cross section for unpolarized incident electron-positron pairs. At high…

High Energy Physics - Phenomenology · Physics 2019-02-05 Leonard Gamberg , Zhong-Bo Kang , Daniel Pitonyak , Marc Schlegel , Shinsuke Yoshida

Based on the nonrelativistic QCD factorization approach, ${\mathcal O}(\alpha_s v^2)$ corrections to $\jpsi$ plus $\eta_c$ production in $e^+e^-$ annihilation at $\sqrt{s}=10.6 \gev$ is calculated in this work. The numerical results show…

High Energy Physics - Phenomenology · Physics 2015-06-12 Xi-Huai Li , Jian-Xiong Wang

A simple quark-diquark model for nucleon and $\Lambda$ structure is used to calculate leading twist light-cone fragmentation functions for a quark to inclusively decay into P or $\Lambda$. The parameters of the model are determined by…

High Energy Physics - Phenomenology · Physics 2016-09-01 Muhammad Nzar , Pervez Hoodbhoy

We make a systematic study of $\Lambda$ hyperon polarizations in unpolarized lepton induced semi-inclusive reactions such as $e^-N\to e^-\Lambda X$ and $e^+e^-\to\Lambda h X$. We present the general form of cross sections in terms of…

High Energy Physics - Phenomenology · Physics 2022-03-14 Kai-bao Chen , Zuo-tang Liang , Yu-kun Song , Shu-yi Wei

Higher-order QED radiative corrections to muon decay spectrum are evaluated within the QED structure function approach in the next-to-leading order logarithmic approximation. New analytical results are given in the…

High Energy Physics - Phenomenology · Physics 2023-12-19 A. B. Arbuzov , U. E. Voznaya

We review the present status of polarized structure functions measured in deep-inelastic scattering. We discuss the x and Q^2 dependence of the structure function g_1, and how it can be used to test perturbative QCD at next-to-leading order…

High Energy Physics - Phenomenology · Physics 2008-02-03 Stefano Forte

We present a quark-parton model to describe polarized and unpolarized nucleon structure functions. The twist-two matrix elements for the QCD evolution analysis of lepton-hadron scattering are calculated within a light-front covariant quark…

High Energy Physics - Phenomenology · Physics 2011-04-15 Marco Traini , Pietro Faccioli , Vicente Vento

We calculate the polarisation of $\psi$'s and $\Upsilon$'s produced by the fragmentation of heavy quarks. We find that fragmentation to transversely aligned quarkonium is slightly enhanced relative to longitudinally polarised. This net…

High Energy Physics - Phenomenology · Physics 2009-10-22 Adam F. Falk , Michael Luke , Martin J. Savage , Mark B. Wise

The universal fragmentation functions of gluon into the flavored quarkonia $B_c$ and (polarized) $B_c^*$ are computed within NRQCD factorization framework, at the lowest order in velocity expansion and strong coupling constant. It is…

High Energy Physics - Phenomenology · Physics 2022-10-12 Feng Feng , Yu Jia , Deshan Yang

We study the effects of QCD corrections to the process $e^+e^-\rightarrow t\bar t+X\rightarrow b\ell^+\nu \bar b\ell^-\bar \nu+X$ above threshold. We show how to treat consistently to ${\cal O}(\alpha_s)$ the gluon radiation in both the…

High Energy Physics - Phenomenology · Physics 2009-10-28 Carl R. Schmidt

We propose the formulation of a dihadron fragmentation function in terms of parton matrix elements. Under the collinear factorization approximation and facilitated by the cut-vertex technique, the two hadron inclusive cross section at…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. Majumder

Fragmentation functions of pion, kaon, and nucleon are determined by global analyses of hadron-production data in $e^+e^-$ annihilation. It is particularly important that uncertainties of the fragmentation functions are estimated for the…

High Energy Physics - Phenomenology · Physics 2007-09-25 M. Hirai , S. Kumano , T. -H. Nagai , M. Oka , K. Sudoh

A new representation of the next to leading QCD corrections to the nucleon structure functions is given in terms of parton distributions. All $~\alpha_{s}~$ corrections to the leading logarithmic approximation (LLA) are included. In…

High Energy Physics - Phenomenology · Physics 2015-06-25 D. B. Stamenov

We recover in QCD an amazingly simple relationship between the anomalous dimensions, resummed through next-to-next-to-leading-logarithmic order, in the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi evolution equations for the first Mellin…

High Energy Physics - Phenomenology · Physics 2017-02-13 Bernd A. Kniehl , Anatoly V. Kotikov

Modified quark fragmentation functions in deeply inelastic $eA$ collisions and their QCD evolution equations are derived for the first time in the framework of multiple parton scattering. Induced radiation gives rise to additional terms in…

High Energy Physics - Phenomenology · Physics 2008-11-26 Xiaofeng Guo , Xin-Nian Wang

The gluino-induced contributions to the decay b-> s gamma are investigated in supersymmetric frameworks with generic sources of flavour violation. It is shown that, when QCD corrections are taken into account, the relevant operator basis of…

High Energy Physics - Phenomenology · Physics 2011-01-05 F. Borzumati , C. Greub , T. Hurth , D. Wyler