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Related papers: Soft Collinear Effective Theory

200 papers

We construct the Lagrangian for an effective theory of highly energetic quarks with energy Q, interacting with collinear and soft gluons. This theory has two low energy scales, the transverse momentum of the collinear particles, p_perp, and…

High Energy Physics - Phenomenology · Physics 2009-10-31 Christian W. Bauer , Sean Fleming , Dan Pirjol , Iain W. Stewart

We study exclusive radiative decays of the $\Upsilon$ using soft-collinear effective theory and non-relativistic QCD. In contrast to inclusive radiative decays at the endpoint we find that color-octet contributions are power suppressed in…

High Energy Physics - Phenomenology · Physics 2009-11-10 Sean Fleming , Christopher Lee , Adam K. Leibovich

We derive a factorization formula for coherent and incoherent $ep$ diffraction using the soft collinear effective theory, utilizing multiple power expansion parameters to handle different kinematic regions. This goes beyond the known…

High Energy Physics - Phenomenology · Physics 2025-12-02 Kyle Lee , Stella T. Schindler , Iain W. Stewart

These lectures provide an introduction to Soft-Collinear Effective Theory. After discussing the expansion of Feynman diagrams around the high-energy limit, the effective Lagrangian is constructed, first for a scalar theory, then for QCD.…

High Energy Physics - Phenomenology · Physics 2020-08-21 Thomas Becher , Alessandro Broggio , Andrea Ferroglia

In this talk I will discuss non-leptonic B decays, in particular how soft-collinear effective field theory (SCET) can be used to constrain the non-perturbative hadronic parameters required to describe the various observables.

High Energy Physics - Phenomenology · Physics 2007-05-23 Christian W. Bauer

We analyze the end-point region of the photon spectrum in semi-inclusive radiative decays of very heavy quarkonium (m alpha_s^2 >> Lambda_QCD). We discuss the interplay of the scales arising in the Soft-Collinear Effective Theory, m,…

High Energy Physics - Phenomenology · Physics 2009-11-10 Xavier Garcia i Tormo , Joan Soto

I review the theoretical ideas and concepts along the line of factorization in the exclusive B decays. In order to understand the naive factorization, the effective field theories and the perturbative method of QCD are introduced and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Zheng-Tao Wei

After the discovery of a new resonance, its couplings to the Standard Model (SM) need to be described by the means of an effective theory, appropriately constructed to separate its mass scale from the mass scales associated with the SM…

High Energy Physics - Phenomenology · Physics 2019-05-17 Matthias König

I give an overview of the theory of hadronic nonleptonic B decays into two light mesons. Using the soft-collinear effective theory (SCET), a factorization theorem for these processes has been proven to leading order in 1/mb. The…

High Energy Physics - Phenomenology · Physics 2008-11-26 Dan Pirjol

Soft-collinear effective theory is used to prove factorization of the B->gamma+l+nu decay amplitude at leading power in Lambda/m_b, including a demonstration of the absence of non-valence Fock states and of the finiteness of the convolution…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. W. Bosch , R. J. Hill , B. O. Lange , M. Neubert

The factorization of soft and ultrasoft gluons from collinear particles is shown at the level of operators in an effective field theory. Exclusive hadronic factorization and inclusive partonic factorization follow as special cases. The…

High Energy Physics - Phenomenology · Physics 2008-11-26 Christian W. Bauer , Dan Pirjol , Iain W. Stewart

We consider various symmetries present in the collinear effective theory and their implications. There are collinear, soft and ultrasoft gauge symmetries and we discuss transformation properties of a collinear quark and gauge fields under…

High Energy Physics - Phenomenology · Physics 2007-05-23 Junegone Chay , Chul Kim

It has recently been argued that soft-collinear effective theory for processes involving both soft and collinear partons contains a new soft-collinear mode, which can communicate between the soft and collinear sectors of the theory. The…

High Energy Physics - Phenomenology · Physics 2009-11-10 Thomas Becher , Richard J. Hill , Bjoern O. Lange , Matthias Neubert

Leptoquarks enter in several extensions of the Standard Model as possible solutions to a number of observed anomalies. We work within the soft-collinear effective theory framework to present a detailed analysis of the decay rates of the…

High Energy Physics - Phenomenology · Physics 2022-11-17 Bianka Mecaj , Matthias Neubert

The factorization properties of the radiative decays B->V gamma are analyzed at leading order in 1/m_b using the soft-collinear effective theory. It is shown that the decay amplitudes can be expressed in terms of a B->V form factor…

High Energy Physics - Phenomenology · Physics 2008-11-26 Thomas Becher , Richard J. Hill , Matthias Neubert

An important unresolved question in strong interaction physics concerns the parameterization of power-suppressed long-distance effects to hard processes that do not admit an operator product expansion (OPE). Recently Bauer et al.\ have…

High Energy Physics - Phenomenology · Physics 2011-05-05 M. Beneke , A. P. Chapovsky , M. Diehl , Th. Feldmann

We study the evolution of flavor-singlet, light-cone amplitudes in the soft-collinear effective theory (SCET), and reproduce results previously obtained by a different approach. We apply our calculation to the color-singlet contribution to…

High Energy Physics - Phenomenology · Physics 2016-09-06 Sean Fleming , Adam K. Leibovich

We discuss the most general form of the leading power suppressed collinear operators in the soft-collinear effective theory. Such operators appear in the description of power corrections to exclusive heavy flavor decays into energetic light…

High Energy Physics - Phenomenology · Physics 2009-11-10 Andri Hardmeier , Enrico Lunghi , Dan Pirjol , Daniel Wyler

We consider a collinear effective theory of highly energetic quarks with energy E, interacting with collinear and soft gluons by integrating out collinear degrees of freedom to subleading order. The collinear effective theory offers a…

High Energy Physics - Phenomenology · Physics 2014-11-17 Junegone Chay , Chul Kim

Heavy-to-light transition form factors at large recoil energy of the light meson have been conjectured to obey a factorization formula, where the set of form factors is reduced to a smaller number of universal form factors up to…

High Energy Physics - Phenomenology · Physics 2010-04-06 M. Beneke , Th. Feldmann