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TTP11-31 Complete QCD corrections to Hadronic Z–Decays in Order \alpha_s4
P. A. Baikov, K. G. Chetyrkin, J. H. Kühn and J. Rittinger
Phys.Rev.Lett. 108 222003 2012
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TTP11-30 Minimal Flavour Violation and Neutrino Masses without R-parity
Giorgio Arcadi, Luca Di Luzio, Marco Nardecchia
JHEP 1205 22 2012
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TTP11-29 The MSSM with a softly broken U(2)³ flavor symmetry
Andreas Crivellin, Lars Hofer and Ulrich Nierste
PoS EPS HEP2011 145 2011
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TTP11-28 Loop-induced photon spectral lines from neutralino annihilation in the NMSSM.

TTP11-28 Loop-induced photon spectral lines from neutralino annihilation in the NMSSM.

We have computed the loop-induced processes of neutralino annihilation into two photons and, for the first time, into a photon and a Z boson in the framework of the NMSSM. The photons produced from these radiative modes are monochromatic and possess a clear „smoking gun“ experimental signature. This numerical analysis has been done with the help of the SloopS code, initially developed for automatic one-loop calculation in the MSSM. We have computed the rates for different benchmark points coming from SUGRA and GMSB soft SUSY breaking scenarios and compared them with the MSSM. We comment on how this signal can be enhanced, with respect to the MSSM, especially in the low mass region of the neutralino. We also discuss the possibility of this observable to constrain the NMSSM parameter space, taking into account the latest limits from the FERMI collaboration on these two modes.

G. Chalons, A. Semenov
JHEP 1112 055 2011
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TTP11-27 Vector-boson production at the LHC: QCD and electroweak effects
Tobias Kasprzik
PoS EPS-HEP2011 358 2011
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TTP11-26 Charge asymmetries of top quarks at hadron colliders revisited

TTP11-26 Charge asymmetries of top quarks at hadron colliders revisited

A sizeable difference in the differential production cross section of top- compared to antitop-quark production, denoted charge asymmetry, has been observed at the Tevatron. The experimental results seem to exceed the theory predictions based on the Standard Model by a significant amount and have triggered a large number of suggestions for „new physics“. In the present paper the Standard Model predictions for Tevatron and LHC experiments are revisited. This includes a reanalysis of electromagnetic as well as weak corrections, leading to a shift of the asymmetry by roughly a factor 1.1 when compared to the results of the first papers on this subject. The impact of cuts on the transverse momentum of the top-antitop system is studied. Restricting the ttbar system to a transverse momentum less than 20 GeV leads to an enhancement of the asymmetries by factors between 1.3 and 1.5, indicating the importance of an improved understanding of the $t\bar t$-momentum distribution. Predictions for similar measurements at the LHC are presented, demonstrating the sensitivity of the large rapidity region both to the Standard Model contribution and effects from „new physics“.

Johann H. Kühn, German Rodrigo
JHEP 1201 063 2012
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TTP11-25 Low- and High-Energy Expansion of Heavy-Quark Correlators at Next-To-Next-To-Leading Order

TTP11-25 Low- and High-Energy Expansion of Heavy-Quark Correlators at Next-To-Next-To-Leading Order

We calculate three-loop corrections to correlation functions of heavy-quark currents in the low- and high-energy regions. We present 30 coefficients both in the low-energy and the high-energy expansion of the scalar and the vector correlator with non-diagonal flavour structure. In addition we compute 30 coefficients in the high-energy expansion of the diagonal vector, axial-vector, scalar and pseudo-scalar correlators. Possible applications of our new results are improvements of lattice-based quark-mass determinations and the approximate reconstruction of the full momentum dependence of the correlators.

A. Maier, P. Marquard
Nucl.Phys. B859 1-12 2012
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TTP11-24 Gluino-Squark Production at the LHC: The Threshold
Matthias R. Kauth, Achim Kress and Johann H. Kuehn
JHEP 1112 104 2011
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TTP11-23 Electroweak corrections to monojet production at the LHC
Ansgar Denner, Stefan Dittmaier, Tobias Kasprzik, Alexander Mück
Eur.Phys.J. C73 2297 2013
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TTP11-22 Gluino Pair Production at the LHC: The Threshold
Matthias R. Kauth, Johann H. Kuehn, Peter Marquard and Matthias Steinhauser
Nucl.Phys. B857 28-64 2012
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TTP11-21 Production of scalar and pseudo-scalar Higgs bosons to next-to-next-to-leading order at hadron colliders
Alexey Pak, Mikhail Rogal, Matthias Steinhauser
JHEP 1109 088 2011
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TTP11-20 Master Integrals for Four-Loop Massless Propagators up to Transcendentality Weight Twelve

TTP11-20 Master Integrals for Four-Loop Massless Propagators up to Transcendentality Weight Twelve

We evaluate a Laurent expansion in dimensional regularization parameter $\epsilon=(4-d)/2$ of all the master integrals for four-loop massless propagators up to transcendentality weight twelve, using a recently developed method of one of the present coauthors (R.L.) and extending thereby results by Baikov and Chetyrkin obtained at transcendentality weight seven. We observe only multiple zeta values in our results. Therefore, we conclude that all the four-loop massless propagator integrals, with any integer powers of numerators and propagators, have only multiple zeta values in their epsilon expansions up to transcendentality weight twelve.

R.N. Lee, A.V. Smirnov, V.A. Smirnov
Nucl.Phys. B856 95-110 2012
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TTP11-19 Flavour physics, supersymmetry and grand unification
Ulrich Nierste
Talk given at conference 13-20 Mar 2011. La Thuile, Aosta Valley, Italy
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TTP11-18 Heavy quark and gluino potentials to two loops
Tim Collet, Matthias Steinhauser
Phys.Lett. B704 163-165 2011
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TTP11-17 Higher-Dimension contributions to the D0-D0bar mixing rate
Markus Bobrowski, Alexander Lenz, Ulrich Nierste, Torben Prill
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TTP11-16 Three-loop anomalous dimensions for squarks in supersymmetric QCD
Thomas Hermann, Luminita Mihaila, Matthias Steinhauser
Phys.Lett. B703 51-59 2011
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TTP11-15 Electroweak Precision Observables within a Fourth Generation Model with General Flavour Structure
P. González, J. Rohrwild, M. Wiebusch
Eur.Phys.J. C72 2007 2012
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TTP11-14 Phenomenological consequences of radiative flavor violation in the MSSM
Andreas Crivellin,Lars Hofer,Ulrich Nierste and Dominik Scherer
Phys.Rev. D84: 035030 2011
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TTP11-13 Reduced branching ratio for $H\to AA \to 4\,\tau$ from $A - \eta_b$ mixing
Florian Domingo and Ulrich Ellwanger
JHEP 1106 067 2011
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TTP11-12 Complete next-to-leading order gluino contribution to $b\to s\gamma$ and $b\to sg$
C. Greub, T. Hurth, V. Pilipp, C. Schuepbach, M. Steinhauser
Nucl.Phys. B853 240-276 2011
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TTP11-11 HQET heavy-heavy vertex diagram with two velocities

TTP11-11 HQET heavy-heavy vertex diagram with two velocities

The one-loop HQET heavy–heavy vertex diagram with arbitrary powers of all three denominators and arbitrary residual energies is investigated. Various particular cases in which the result becomes simpler are considered.

A.G.Grozin, A.V.Kotikov
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TTP11-10 Probing new physics in electroweak penguins through Bd and Bs decays
Lars Hofer, Dominik Scherer, Leonardo Vernazza
J.Phys.Conf.Ser. 335 012039 2011
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TTP11-09 Integration by parts: An introduction

TTP11-09 Integration by parts: An introduction

Integration by parts is used to reduce scalar Feynman integrals to master integrals.

Andrey Grozin
Int.J.Mod.Phys. A26 2807-2854 2011
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TTP11-08 Next-to-Next-to-Leading Electroweak Logarithms for W-Pair Production at LHC.
J.H. Kuhn, F. Metzler (Karlsruhe U., TTP), A.A. Penin (Alberta U. & Moscow, INR), S. Uccirati (Wurzburg U.).
JHEP 1106 143 2011
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TTP11-07 Simultaneous decoupling of bottom and charm quarks
Andrey G. Grozin, Maik Höschele, Jens Hoff and Matthias Steinhauser
JHEP 1109 066 2011
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TTP11-06 On Epsilon Expansions of Four-loop Non-planar Massless Propagator Diagrams

TTP11-06 On Epsilon Expansions of Four-loop Non-planar Massless Propagator Diagrams

We evaluate three typical four-loop non-planar massless propagator diagrams in a Taylor expansion in dimensional regularization parameter $\epsilon=(4-d)/2$ up to transcendentality weight twelve, using a recently developed method of one of the present coauthors (R.L.). We observe only multiple zeta values in our results.

R.N. Lee and A.V. Smirnov and V.A. Smirnov
Eur.Phys.J. C71 1708 2011
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TTP11-05 Running and decoupling of $\alpha_s$
Matthias Steinhauser
Contribution to the proceedings of the workshop „alphas 2011“
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TTP11-04 Electroweak corrections to dilepton + jet production at hadron colliders
Ansgar Denner, Stefan Dittmaier, Tobias Kasprzik, Alexander Mück
JHEP 1106 069 2011
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TTP11-03 Numerical updates of lifetimes and mixing parameters of B mesons
Alexander Lenz and Ulrich Nierste
To appear in the proceedings of Conference: C10-09-06
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TTP11-02 Moments of heavy-light current correlators up to three loops
J. Hoff, M. Steinhauser
Nucl.Phys. B849 610-627 2011
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TTP11-01 $W$ mass and Leptonic $Z$-decays in the NMSSM
Florian Domingo and Teresa Lenz
JHEP 1107 101 2011
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