Institute for Theoretical Particle Physics (TTP)

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TTP15-046 Six loop analytical calculation of the field anomalous dimension and the critical exponent $\eta$ in $O(n)$-symmetric $\phi^4$ model
D.V. Batkovich, K.G. Chetyrkin and M.V. Kompaniets
Nucl.Phys. B906 (2016) 147-167
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TTP15-045 Electroweak corrections in top-quark physics (1)

TTP15-045 Electroweak corrections in top-quark physics (1)

Electroweak corrections for inclusive top-quark pair production are reviewed and updated results for the weak corrections taking into account the recently measured Higgs mass are presented.

Johann K\“uhn and Peter Uwer
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TTP15-044 Top-quark pair production close to threshold at hadron colliders: an update

TTP15-044 Top-quark pair production close to threshold at hadron colliders: an update

QCD and weak corrections for top-antitop production at the LHC are presented with emphasis on their behaviour in the threshold region.

Johann Kühn and Peter Uwer
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TTP15-043 Gluino Meets Flavored Naturalness
Monika Blanke, Benjamin Fuks, Iftah Galon, Gilad Perez
JHEP 1604 (2016) 044
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TTP15-042 The Pentabox Master Integrals with the Simplified Differential Equations approach
C. Papadopoulos, D. Tommasini and C.S.P. Wever
JHEP 1604 (2016) 078
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TTP15-041 QCD corrections to W+W- production through gluon fusion
Fabrizio Caola, Kirill Melnikov, Raoul Röntsch, Lorenzo Tancredi
Phys.Lett. B754 275-280 2016
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TTP15-040 $\alpha_s$ from $\sigma(e^+ e^- \to$ hadrons)
K. G. Chetyrkin and J. H. Kühn
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TTP15-039 Quantum theory from questions
Philipp Andres Höhn and Christopher Wever
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TTP15-038 Higher order hadronic and leptonic contributions to the muon $g-2$
Alexander Kurz, Tao Liu, Peter Marquard, Alexander V. Smirnov, Vladimir A. Smirnov, Matthias Steinhauser
EPJ Web Conf. 118 (2016) 01033
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TTP15-037 ATLAS on-Z Excess via gluino-Higgsino-singlino decay chains in the NMSSM
Keisuke Harigaya, Masahiro Ibe, Teppei Kitahara
JHEP 1601 030 2016
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TTP15-036 FIESTA4: optimized Feynman integral calculations with GPU support
Alexander Smirnov
Comput.Phys.Commun. 204 (2016) 189-199
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TTP15-035 QCD corrections to ZZ production in gluon fusion at the LHC
F. Caola, K. Melnikov, R. Rontsch, L. Tancredi
Phys.Rev. D92 9, 094028 2015
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TTP15-034 Integration by parts identities in integer numbers of dimensions. A criterion for decoupling systems of differential equations
Lorenzo Tancredi
Nucl.Phys. B901 282-317 2015
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TTP15-033 Charge and color breaking constraints in the Minimal Supersymmetric Standard Model associated with the bottom Yukawa coupling

TTP15-033 Charge and color breaking constraints in the Minimal Supersymmetric Standard Model associated with the bottom Yukawa coupling

Testing the stability of the electroweak vacuum in any extension of the Standard Model Higgs sector is of great importance to verify the consistency of the theory. Multi-scalar extensions as the Minimal Supersymmetric Standard Model generically lead to unstable configurations in certain regions of parameter space. An exact minimization of the scalar potential is rather an impossible analytic task. To give handy analytic constraints, a specific direction in field space has to be considered which is a simplification that tends to miss excluded regions, however good to quickly check parameter points. We describe a yet undescribed class of charge and color breaking minima as they appear in the Minimal Supersymmetric Standard Model, exemplarily for the case of non-vanishing bottom squark vacuum expectation values constraining the combination mu Yb in a non-trivial way. Contrary to famous A-parameter bounds, we relate the bottom Yukawa coupling with the supersymmetry breaking masses. Another bound can be found relating soft breaking masses and mu only. The exclusions follow from the tree-level minimization and can change dramatically using the one-loop potential. Estimates of the lifetime of unstable configurations show that they are either extremely short- or long-lived.

Wolfgang Gregor Hollik
Phys. Lett. B752 7-12 2016
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TTP15-032 Phenomenological aspects of flavoured dark matter
Monika Blanke
PoS EPS-HEP2015 (2015) 390
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TTP15-031 Top-Yukawa effects on the beta-function of the strong coupling in the SM at four-loop level
M. F. Zoller
JHEP 1602 095 2016
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TTP15-030 Fiducial volume cross sections for Higgs boson production in association with a jet at NNLO in perturbative QCD
F. Caola, K. Melnikov, M. Schulze
Phys.Rev. D92 7, 074032 2015
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TTP15-029 $\Gamma(H\to b\bar{b})$ to order $\alpha\alpha_s$
Luminita Mihaila, Barbara Schmidt, Matthias Steinhauser
Phys.Lett. B751 442-447 2015
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TTP15-028 The $O(a_s^3)$ Heavy Flavor Contributions to the Charged Current Structure Function $x F_3(x, Q^2)$ at Large Momentum Transfer
Arnd Behring, Johannes Blümlein, Abilio De Freitas, Alexander Hasselhuhn, Andreas von Manteuffel, Carsten Schneider
Phys.Rev. D92 11, 114005 2015
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TTP15-027 CP Violation in D0->KSKS
Ulrich Nierste, Stefan Schacht
Phys.Rev. D92 5, 054036 2015
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TTP15-026 Higgs boson pair production: top quark mass effects at NLO and NNLO
Jonathan Grigo, Jens Hoff, Matthias Steinhauser
Nucl.Phys. B900 412-430 2015
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TTP15-025 Light-by-light-type corrections to the muon anomalous magnetic moment at four-loop order
Alexander Kurz, Tao Liu, Peter Marquard, Alexander V. Smirnov, Vladimir A. Smirnov, Matthias Steinhauser
Phys.Rev. D92 7, 073019 2015
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TTP15-024 Leptogenesis in an SU(5) x A5 Golden Ratio Flavour Model:Addendum
Julia Gehrlein, Serguey T. Petcov, Martin Spinrath, Xinyi Zhang
Nucl.Phys. B899 617-630 2015
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TTP15-023 Quark flavour observables in the Littlest Higgs model with T-parity after LHC Run 1
Monika Blanke, Andrzej J. Buras, Stefan Recksiegel
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TTP15-022 Renormalisation Group Corrections to Neutrino Mass Sum Rules
J. Gehrlein, A. Merle, M. Spinrath
JHEP 1509 066 2015
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TTP15-021 Next-to-next-to-next-to-leading order QCD prediction for the top anti-top S-wave pair production cross section near threshold in $e^+ e^-$ annihilation
Martin Beneke, Yuichiro Kiyo, Peter Marquard, Alexander Penin, Jan Piclum, and Matthias Steinhauser
Phys.Rev.Lett. 115 19, 192001 2015
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TTP15-020 Sum Rules of Charm CP Asymmetries beyond the SU(3)F Limit
Sarah M\“uller, Ulrich Nierste, Stefan Schacht
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TTP15-019 Exact N$^3$LO results for $q q^\prime\to H +X$
Chihaya Anzai, Alexander Hasselhuhn, Maik H\“oschele, Jens Hoff, William Kilgore, Matthias Steinhauser, Takahiro Ueda
JHEP 1507 140 2015
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TTP15-018 Lepton-flavour violating B decays in generic Z' models

TTP15-018 Lepton-flavour violating B decays in generic Z' models

LHCb has reported deviations from the SM expectations in $B\to K^* \mu^+\mu^-$ angular observables, in $B_s\to\phi\mu^+\mu^-$ and in ratio $R(K)=Br[B\to K \mu^+\mu^-]/Br[B\to K e^+e^-]$. For all three decays, a heavy neutral gauge boson mediating $b\to s\mu^+\mu^-$ transitions is a prime candidate for an explanation. As $R(K)$ measures violation of lepton-flavour universality, it is interesting to examine the possibility that also lepton flavour is violated. In this article, we investigate the perspectives to discover the lepton-flavour violating modes $B\to K^{(*)}\tau^\pm\mu^\mp$, $B_s\to \tau^\pm\mu^\mp$ and $B\to K^{(*)} \mu^\pm e^\mp$, $B_s\to \mu^\pm e^\mp$. For this purpose we consider a simplified model in which new-physics effects originate from an additional neutral gauge boson ($Z^\prime$) with generic couplings to quarks and leptons. The constraints from $\tau\to3\mu$, $\tau\to\mu\nu\bar{\nu}$, $\mu\to e\gamma$, $g_\mu-2$, neutrino trident production, $Z\to\ell^+\ell^{\prime-}$, semi-leptonic $b\to s\mu^+\mu^-$ decays and $B_s$–$\overline{B}_s$ mixing are examined. Taking into account these limits, we determine upper bounds on the decay rates of $B\to K^{(*)}\tau^\pm\mu^\mp$, $B_s\to \tau^\pm\mu^\mp$, $B\to K^{(*)}\mu^\pm e^\mp$ and $B_s\to \mu^\pm e^\mp$ as a function of fine-tuning in $B_s$–$\overline{B}_s$ mixing. We find that for a significant degree of fine-tuning the effect in all considered decays with $\tau\mu$ final states can be sizable (leading to branching ratios of the order of $\times 10^{-6}$). For $\mu e$ final states, $B_s\to \mu^\pm e^\mp$ is strongly suppressed and only $B\to K^{(*)} \mu^\pm e^\mp$ can be relevant (of the order of $\times 10^{-7}$). However, this is only possible in a region of the parameter space disfavoured by the current LHCb data on $b\to s\mu^+\mu^-$ transitions.

Andreas Crivellin, Lars Hofer, Joaquim Matias, Ulrich Nierste, Stefan Pokorski, Janusz Rosiek
Phys.Rev. D92 (2015) 5, 054013 D92 5, 054013 2015
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TTP15-017 Higgs boson production in association with a jet at next-to-next-to-leading order
R. Boughezal, F. Caola, K. Melnikov, F. Petriello, M. Schulze
Phys.Rev.Lett. 115 8, 082003 2015
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TTP15-016 Neutrino Mixing from SUSY breaking

TTP15-016 Neutrino Mixing from SUSY breaking

We propose a mechanism to generate the neutrino mixing matrix from supersymmetric threshold corrections. Flavor violating soft breaking terms induce flavor changing self-energies that give a finite renormalization to the mixing matrix. The described threshold corrections get enhanced in case of quasi-degenerate neutrino masses. In this scenario, we adjust potentially arbitrary soft breaking parameters in a way to reproduce the observed neutrino mixing at one loop working with non-minimal flavor violating soft parameters. To incorporate small neutrino masses already at tree-level via a type I seesaw mechanism, we extend the Minimal Supersymmetric Standard Model with singlet Majorana neutrinos. The radiative corrections do not decouple with the scale of Supersymmetry and persist when the spectrum is shifted to higher values. Moreover, the mixing matrix renormalization with flavor-changing self-energies is not restricted to supersymmetric theories and give similar results in any theory with new flavor structures.

Wolfgang G. Hollik
PoS CORFU2014 (2015) 077
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TTP15-015 Topological amplitudes in D decays to two pseudoscalars: a global analysis with linear SU(3)F breaking
Sarah Müller, Ulrich Nierste, Stefan Schacht
Phys.Rev. D92 1, 014004 2015
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TTP15-014 The two-loop helicity amplitudes for gg -> V V' -> 4-leptons
A. von Manteuffel, L. Tancredi
JHEP 1506 197 2015
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TTP15-013 Two-loop helciity amplitudes for the production of two off-shell electroweak bosons in gluon fusion
F. Caola, J. Henn, K. Melnikov, A. Smirnov, V. Smirnov
JHEP 1506 129 2015
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TTP15-012 The Strong CP Problem and Discrete Symmetries
Martin Spinrath
Mod.Phys.Lett. A30 19,1530014 2015
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TTP15-011 The two-loop helicity amplitudes for qqb -> V V' -> 4-leptons
T. Gehrmann, A. von Manteuffel, L. Tancredi
JHEP 1509 128 2015
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TTP15-010 Penguin contributions to CP phases in B_{d,s} decays to charmonium
Philipp Frings, Ulrich Nierste , and Martin Wiebusch
Phys.Rev.Lett. 115 061802 2015
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TTP15-009 Production of two Z bosons in gluon fusion in the heavy top quark approximation
Kirill Melnikov, Matthew Dowling
Phys.Lett. B744 43-47 2015
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TTP15-008 The (Q_7,Q_{1,2}) contribution to $\bar B\to X_s\gamma$ at O(alpha_s2)
Michak Czakon, Paul Fiedler, Tobias Huber, Mikolaj Misiak, Thomas Schutzmeier, Matthias Steinhauser
JHEP 1504 168 2015
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TTP15-007 Updated NNLO QCD predictions for the weak radiative $B$-meson decays
M. Misiak, M. Steinhauser et al.
Phys.Rev.Lett. 114 22, 221801 2015
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TTP15-006 Penguin contributions to CP phases in B_{d,s} decays to charmonium
Philipp Frings, Ulrich Nierste , and Martin Wiebusch
Phys.Rev.Lett. 115 061802 2015
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TTP15-005 Decoupling of heavy quarks at four loops and effective Higgs-fermion coupling
Tao Liu and Matthias Steinhauser
Phys.Lett. B746 330-334 2015
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TTP15-004 Non-minimally flavour violating dark matter

TTP15-004 Non-minimally flavour violating dark matter

Flavour symmetries provide an appealing mechanism to stabilize the dark matter particle. I present a simple model of quark flavoured dark matter that goes beyond the framework of minimal flavour violation. I discuss the phenomenological implications for direct and indirect dark matter detection experiments, high energy collider searches as well as flavour violating precision data.

Monika Blanke
J.Phys.Conf.Ser. 631 012022 2015
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TTP15-003 Leptogenesis in an SU(5) x A5 Golden Ratio Flavour Model
Julia Gehrlein, Serguey T. Petcov, Martin Spinrath, Xinyi Zhang
Nucl.Phys. B896 311-329 2015
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TTP15-002 Massless Propagators, R(s) and Multiloop QCD
P. A. Baikov, K. G. Chetyrkin, J. H. K\“uhn
Nucl.Part.Phys.Proc. 261-262 3-18 2015
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TTP15-001 Quark mass relations to four-loop order
Peter Marquard, Alexander V. Smirnov, Vladimir A. Smirnov, Matthias Steinhauser
Phys.Rev.Lett. 114 14, 142002 2015
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