Parton distributions in the virtual photon target up to NNLO in QCD (2009)
Ueda, Takahiro, Sasaki, Ken, Uematsu, Tsuneo
Parton distributions in the virtual photon target are investigated in perturbative QCD up to the next-to-next-to-leading order (NNLO). In the case $\Lambda^2 \ll P^2 \ll Q^2$, where $-Q^2$ ($-P^2$)...
Heavy Quark Effects in the Virtual Photon Structure Functions (2008)
Kitadono, Yoshio, Sasaki, Ken, Ueda, Takahiro, Uematsu, Tsuneo
We investigate the heavy quark mass effects in the virtual photon structure functions $F_{2}^{\gamma}(x, Q^2, P^2)$ and $F_{L}^{\gamma}(x, Q^2, P^2)$ in the framework of the mass-independent...
NNLO QCD analysis of the virtual photon structure functions (2008)
Sasaki, Ken, Ueda, Takahiro, Kitadono, Yoshio, Uematsu, Tsuneo
The next-to-next-to-leading order (NNLO) QCD analysis is performed for the virtual photon structure functions which can be measured in the double-tag events in two-photon processes in $e^+e^-$...
Virtual Photon Structure Functions to NNLO in QCD (2008)
Ueda, Takahiro, Uematsu, Tsuneo, Sasaki, Ken
The unpolarized virtual photon structure functions $F_2^\gamma(x,Q^2,P^2)$ and $F_L^\gamma(x,Q^2,P^2)$ are investigated in perturbative QCD for the kinematical region $\Lambda^2 \ll P^2 \ll Q^2$,...
Kitadono, Yoshio, Sasaki, Ken, Ueda, Takahiro, Uematsu, Tsuneo
We investigate target mass effects in the unpolarized virtual photon structure functions $F_2^\gamma(x,Q^2,P^2)$ and $F_L^\gamma(x,Q^2,P^2)$ in perturbative QCD for the kinematical region $\Lambda^2...
Virtual photon structure functions and positivity constraints (2006)
Sasaki, Ken, Soffer, Jacques, Uematsu, Tsuneo
We study the three positivity constraints among the eight virtual photon structure functions, derived from the Cauchy-Schwarz inequality and which are hence model-independent. The photon structure...
Mass effects in the polarized virtual photon structure (2004)
We discuss target mass effects in the polarized virtual photon structure functions $g_1^\gamma (x,Q^2,P^2)$, $g_2^\gamma (x,Q^2,P^2)$ for the kinematic region $\Lambda^2\ll P^2 \ll Q^2$, where $-Q^2...
Target Mass Effects in Polarized Virtual Photon Structure Functions (2003)
Baba, Hideshi, Sasaki, Ken, Uematsu, Tsuneo
We study target mass effects in the polarized virtual photon structure functions $g_1^\gamma (x,Q^2,P^2)$, $g_2^\gamma (x,Q^2,P^2)$ in the kinematic region $\Lambda^2\ll P^2 \ll Q^2$, where $-Q^2...
Virtual Photon Structure Functions (2002)
We discuss the perturbatively calculable virtual photon structure functions. First we present the framework for analyzing the structure functions of the virtual photon and derive a first moment of...
Virtual photon structure functions and positivity constraints (2002)
Sasaki, Ken, Soffer, Jacques, Uematsu, Tsuneo
We study the three positivity constraints among the eight virtual photon structure functions, derived from the Cauchy-Schwarz inequality and which are hence model-independent. The photon structure...
Twist-3 Effects in Polarized Photon Structure (2002)
Baba, Hideshi, Sasaki, Ken, Uematsu, Tsuneo
The polarized photon structure is described by two spin structure functions $g_1^\gamma$ and $g_2^\gamma$ which can be studied in the future polarized ep or e$^+$e$^-$ colliders. Here we investigate...
Polarized Photon Structure: $g_1^\gamma$ and $g_2^\gamma$ (2002)
Baba, Hideshi, Sasaki, Ken, Uematsu, Tsuneo
We investigate the polarized photon structure functions $g_1^\gamma$ and $g_2^\gamma$ which can be studied in the future polarized version of ep or e$^+$e$^-$ colliders. The NLO QCD calculations of...
Polarized Virtual Photon Structure Function $g_2^\gamma$ and Twist-3 Effects in QCD (2002)
Baba, Hideshi, Sasaki, Ken, Uematsu, Tsuneo
We investigate the twist-3 effects in the polarized virtual photon structure. The structure functions $g_1^\gamma$ and $g_2^\gamma$ of polarized photon could be experimentally studied in the future...
Nonlinear Realization of Partially Broken N=2 AdS Supersymmetry in Two and Three Dimensions (2000)
Sano, Masayuki, Uematsu, Tsuneo
We investigate the nonlinear realization of partially broken $N$=2 global supersymmetry in the D=2 and 3 anti de-Sitter (AdS) space. We particularly study Nambu-Goldstone degrees of freedom for the...
Generating All Wigner Functions (2000)
Curtright, Thomas, Uematsu, Tsuneo, Zachos, Cosmas
In the context of phase-space quantization, matrix elements and observables result from integration of c-number functions over phase space, with Wigner functions serving as the quasi-probability...
Polarized and Unpolarized Structures of the Virtual Photon (2000)
We discuss the structure functions and the parton distributions in the virtual photon target, both polarized and unpolarized, beyond the leading order in QCD. We study the factorization-scheme...
Factorization Scheme and Parton Distributions in the Polarized Virtual Photon Target (2000)
We investigate spin-dependent parton distributions in the polarized virtual photon target in perturbative QCD up to the next-to-leading order (NLO). In the case $\Lambda^2 \ll P^2 \ll Q^2$, where...
Parton Distributions in the Virtual Photon Target and Factorization Scheme Dependence (2000)
We investigate parton distributions in the virtual photon target, both polarized and unpolarized, up to the next-leading order (NLO) in QCD. Parton distributions can be predicted completely up to...
Polarized Parton Distributions in the Photon and Factorization Scheme Dependence (1999)
Spin-dependent parton distributions in the polarized virtual photon are investigated in QCD up to the next-to-leading order (NLO). In the case $\Lambda^2 \ll P^2 \ll Q^2$, where $-Q^2$ ($-P^2$) is...
Spin structure function of the virtual photon (1999)
We investigate the spin structure of the virtual photon beyond the leading order in QCD. The first moment of the virtual photon spin structure function $g_1^\gamma(x,Q^2,P^2)$ with QCD effects turns...
Spin Structure Function of the Virtual Photon Beyond the Leading Order in QCD (1998)
Polarized photon structure can be studied in the future polarized $e^{+}e^{-}$ colliding-beam experiments. We investigate the spin-dependent structure function of the virtual photon...
Polarized Virtual Photon Structure Function in the Next-to-leading Order in QCD (1998)
The virtual photon structure function $g_1^{\gamma}(x,Q^2,P^2)$, which can be obtained in polarized $e^{+}e^{-}$ colliding-beam experiments, is investigated for $\Lambda^2 \ll P^2 \ll Q^2$, where...
Nonlinear Realization of Partially Broken N=2 Superconformal Symmetry in Four Dimensions (1997)
Gotoh, Yoshinori, Uematsu, Tsuneo
We investigate the nonlinear realization of spontaneously broken N=2 superconformal symmetry in 4 dimensions. We particularly study Nambu-Goldstone degrees of freedom for the partial breaking of N=2...
QCD Corrections to the nucleon's spin structure function $G_2(x,Q^2)$ (1996)
Kodaira, Jiro, Yasui, Yoshiaki, Tanaka, Kazuhiro, Uematsu, Tsuneo
We investigate the renormalization of the twist-3 operators which are relevant for the spin-dependent structure function $g_{2}(x, Q^{2})$. We derive the anomalous dimension for the non-singlet part...
Higher-twist Effects in Spin Structure Functions (1996)
We discuss the QCD effects of the higher-twist operators in the nucleon spin-dependent structure functions measured by the polarized deep inelastic leptoproduction. We particularly study the...
Renormalization of Twist-4 Operators in QCD Bjorken and Ellis-Jaffe Sum Rules (1996)
Kawamura, Hiroyuki, Uematsu, Tsuneo, Yasui, Yoshiaki, Kodaira, Jiro
The QCD effects of twist-4 operators on the first moment of nucleon spin-dependent structure function $g_1(x, Q^2 )$ are studied in the framework of operator product expansion and renormalization...
Geometry and Duality in Supersymmetric sigma-Models (1996)
Curtright, Thomas, Uematsu, Tsuneo, Zachos, Cosmas
The Supersymmetric Dual Sigma Model (SDSM) is a local field theory introduced to be nonlocally equivalent to the Supersymmetric Chiral nonlinear sigma-Model (SCM), this dual equivalence being proven...
Target Mass Corrections to QCD Bjorken Sum Rule for Nucleon Spin Structure Functions (1995)
KAWAMURA, Hiroyuki, UEMATSU, Tsuneo
We discuss the possible target mass corrections in the QCD analysis of nucleon's spin-dependent structure functions measured in the polarized deep-inelastic leptoproduction. The target mass...
Target Mass Effects in QCD Bjorken Sum Rule (1994)
Kawamura, Hiroyuki, Uematsu, Tsuneo
We investigate the target mass effects in QCD Bjorken sum rule. The magnitude of the target mass correction is estimated in a variety of methods employing positivity bound as well as the experimental...
Spin Structure Function $g_2$ and Twist-3 Operators in QCD (1994)
KODAIRA, Jiro, UEMATSU, Tsuneo, Yasui, Yoshiaki
We investigate the spin structure function $g_2 (x, Q^2 )$ in the framework of the operator product expansion and the renormalization group. The twist-3 operators appearing in QCD are examined and...
More on the Burkhardt-Cottingham Sum Rule in QCD (1994)
Kodaira, Jiro, Matsuda, Satoshi, Uematsu, Tsuneo, Sasaki, Ken
The QCD higher order effects to the polarized structure function $g_2(x, Q^2 )$ are reanalyzed for massive quarks in the context of the operator product expansion. We confirm that the lowest moment...
q-deformed superconformal algebra on quantum superspace (1993)
Kobayashi, Tatsuo, Uematsu, Tsuneo
A quantum deformation of 4-dimensional superconformal algebra realized on quantum superspace is investigated. We study the differential calculus and the action of the quantum generators corresponding...
q-deformed conformal and Poincar{\'e} algebras on quantum 4-spinors (1992)
Kobayashi, Tatsuo, Uematsu, Tsuneo
We investigate quantum deformation of conformal algebras by constructing the quantum space for $sl_q(4,C)$. The differential calculus on the quantum space and the action of the quantum generators are...
Differential Calculus on the Quantum Superspace and Deformation of Phase Space (1992)
Kobayashi, Tatsuo, Uematsu, Tsuneo
We investigate non-commutative differential calculus on the supersymmetric version of quantum space where the non-commuting super-coordinates consist of bosonic as well as fermionic (Grassmann)...
Quantum Conserved Charges and S-matrices in N=2 Supersymmetric Sine-Gordon Theory (1991)
Kobayashi, Ken-ichiro, Uematsu, Tsuneo
We study the quantum conserved charges and S-matrices of N=2 supersymmetric sine-Gordon theory in the framework of perturbation theory formulated in N=2 superspace. The quantum affine algebras...
S-matrix of N=2 Supersymmetric Sine-Gordon Theory (1991)
Kobayashi, Ken-ichiro, Uematsu, Tsuneo
We investigate the S-matrix of N=2 supersymmetric sine-Gordon theory based on the N=2 supersymmetry and the quantum group structure. The topological charges play an important role to derive physical...