Top-quark pair production near threshold at LHC (2008)
Kiyo, Y., Kühn, J. H., Moch, S., Steinhauser, M., Uwer, P.
The next-to-leading order analysis for the cross section for hadroproduction of top quark pairs close to threshold is presented. Within the framework of non-relativistic QCD a significant enhancement...
Ultrasoft contribution to heavy-quark pair production near threshold (2008)
We compute the third-order correction to the heavy-quark current correlation function due to the emission and absorption of an ultrasoft gluon. Our result supplies a missing contribution to top-quark...
NNNLO results on top-quark pair production near threshold (2008)
Beneke, M., Kiyo, Y., Schuller, K.
We present new results on the NNNLO top-antitop production cross section near threshold from potential and ultrasoft gluon corrections. The new non-logarithmic third-order terms are in the 10% range...
NNNLO correction to the toponium and bottomonium wave-functions at the origin (2007)
Beneke, M., Kiyo, Y., Penin, A., Schuller, K.
We report new results of the NNNLO correction to the S-wave quarkonium wave-functions at the origin, which also provide an estimate of the resonance cross section in t-tbar threshold production at...
Ultrasoft contribution to quarkonium production and annihilation (2007)
Beneke, M., Kiyo, Y., Penin, A. A.
We compute the third-order correction to electromagnetic S-wave quarkonium production and annihilation rates due to the emission and absorption of an ultrasoft gluon. Our result completes the...
Third-order non-Coulomb correction to the S-wave quarkonium wave functions at the origin (2007)
Beneke, M., Kiyo, Y., Schuller, K.
We compute the third-order correction to the S-wave quarkonium wave functions |\psi_n(0)|^2 at the origin from non-Coulomb potentials in the effective non-relativistic Lagrangian. Together with...
Third order Coulomb correction to ttbar threshold cross section (2006)
We report on our result of third order Coulomb correction to the cross section sigma(ee -> ttbar) near threshold. Analytic expression for the Coulomb energy and wave function at the origin are...
Report of the 2005 Snowmass Top/QCD Working Group (2006)
Juste, A., Kiyo, Y., Petriello, F., Teubner, T., Agashe, K., Batra, P., ...
This report discusses several topics in both top quark physics and QCD at an International Linear Collider (ILC). Issues such as measurements at the $t\bar{t}$ threshold, including both theoretical...
Beneke, M., Kiyo, Y., Schuller, K.
We obtain analytic expressions for the third-order corrections due to the strong interaction Coulomb potential to the S-wave Green function, energy levels and wave functions at the origin for...
Loop corrections to sub-leading heavy quark currents in SCET (2004)
Beneke, M., Kiyo, Y., Yang, D. S.
We compute the one-loop (hard) matching correction to heavy-to-light transition currents in soft-collinear effective theory (SCET) to sub-leading power in the SCET expansion parameter for an...
Top mass determination and O (alpha_S^5 m) correction to toponium 1S energy level (2002)
Recently the full O(alpha_S^5 m, alpha_S^5 m log(alpha_S)) correction to the heavy quarkonium 1S energy level has been computed (except the a_3-term in the QCD potential). We point out that the full...
We calculate O(alpha_S^4 m) and O(alpha_S^4 m log(alpha_S)) corrections to the quarkonium 1S energy level analytically, which have been overlooked in recent studies. These are the contributions from...
Off-shell Suppression of Renormalons in Non-relativistic QCD Boundstates (2001)
We study an effect of the off-shellness of the quark and antiquark inside a heavy quarkonium system on IR renormalons contained in the perturbative computations of the quarkonium energy levels. We...
Revisiting W gamma production at RHIC (2001)
Kawamura, H., Kiyo, Y., Kodaira, J., Morii, K.
We discuss W gamma production in polarized p p collisions at RHIC energy. We point out that the RHIC collider has two advantages over other hadron colliders to measure the characteristic feature of W...
Top quark mass determination near t\bar{t} threshold at lepton colliders (2001)
Future e^+ e^- linear colliders will enable us to determine the top quark mass with high accuracy from the measurement of the 1S peak position of (remnant of) toponium. The estimated statistical...
Presently the quarkonium spectrum, written in terms of the quark MSbar-mass, is known at O(alpha_s^3 m) accuracy. We point out that in order to achieve O(alpha_s^4 m) accuracy it is sufficient to...
The spin correlation in top quark production: QCD corrections vs anomalous couplings (2000)
Kiyo, Y., Kodaira, J., Morii, K., Nasuno, T., Parke, S.
We discuss top quark production and its subsequent decay at lepton colliders including both QCD corrections and anomalous gamma / Z - t t-bar couplings. The off-diagonal spin basis for the top and...
Penguins diagrams in Delta I=1/2 rule and \epsilon'/\epsilon with \sigma models (1999)
Harada, M., Keum, Y., Kiyo, Y., Morozumi, T., Onogi, T., Yamada, N.
We study the correlation between $\epe$ and $\Delta I=1/2$ rule in the framework of non-linear $\sigma$ model including scalar mesons. The matrix elements of QCD and Electroweak (EW) penguin...
Quark Mass Hierarchy, FCNC and CP violation in a Seesaw model (1998)
Kiyo, Y., Morozumi, T., Parada, P., Rebelo, M. N., Tanimoto, M.
The seesaw model of quark masses is studied systematically, focusing on its developments. A framework allowing the top quark mass to be of the order of the electroweak symmetry breaking scale, while...
More on Large $Q^2$ Events with Polarized Beams (1998)
We discuss polarized proton-positron scattering in the context of the excess of large $Q^2$ events at HERA. We define and estimate a polarized asymmetry to examine two scenarios, the contact...
Kiyo, Y., Morozumi, T., Tanimoto, M.
We investigate the rare decay processes of the K mesons, K_{L,S} -> \pi^0 \nu \bar{\nu} and K^{+} -> \pi^+ \nu \bar{\nu} in LR model with lepton family number being well conserved. In these...
Top Pair Production in $e^{+} e^-$ and $\gamma \gamma$ Processes (1998)
Hori, Masaki, Kiyo, Y, Kodaira, J, Nasuno, T, Parke, S
We analyze spin correlations between top quark and anti-top quark produced at polarized e^+ e^- and gamma gamma colliders. We consider a generic spin basis to find a strong spin correlation. Optimal...
Optimal Spin Basis in Polarized Photon Linear Colliders (1997)
Hori, Masaki, Kiyo, Y, Nasuno, T
We analyze the spin correlations of the top quark pairs produced at Photon Linear Colliders. We employ the circular polarized photon beams and general spin basis for the top quark pair. We consider...
Report of the 2005 Snowmass Top/QCD Working Group
Juste, A., Kiyo, Y., Petriello, F., Teubner, T., Agashe, K., Batra, P., ...
This report discusses several topics in both top quark physics and QCD at an International Linear Collider (ILC). Issues such as measurements at the $t\bar{t}$ threshold, including both theoretical...