Institute for Theoretical Particle Physics (TTP)

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 Recent

TTP14-040 Non-relativistic top production and WIMP annihilation
Martin Beneke, Matthias Steinhauser
Nucl.Part.Phys.Proc. 261-262 378-413 2015
PDF PostScript arXiv
TTP14-039 Massive Tadpoles: Techniques and Applications
K.G. Chetyrkin, J.H. Kühn, M. Steinhauser, C. Sturm
Nucl.Part.Phys.Proc. 261-262 19-30 2015
PDF PostScript arXiv

TTP14-038 Lifting degenerate neutrino masses, threshold corrections and maximal mixing

TTP14-038 Lifting degenerate neutrino masses, threshold corrections and maximal mixing

In the scenario with degenerate neutrino masses at tree-level, we show how threshold corrections with either non-trivial or trivial mixing at tree-level have the power to generate the observed deviations from a degenerate spectrum. Moreover, it is possible to also generate the mixing fully radiatively when there is trivial mixing at tree-level.

We give a brief overview over the topic and discuss the outcome of threshold corrections for degenerate neutrino masses in a supersymmetric model. A detailed description can be found in TTP14-034.

Wolfgang Gregor Hollik
PoS FWNP 018 2014
PDF PostScript arXiv

TTP14-037 Flavoured Dark Matter Beyond MFV

TTP14-037 Flavoured Dark Matter Beyond MFV

We review a model of quark flavoured dark matter with new flavour violating interactions. This simplified model describes Dirac fermionic dark matter that is charged under a new U(3) flavour symmetry and couples to right-handed down quarks via a scalar mediator. The corresponding coupling matrix is assumed to be the only new source of flavour violation, which we refer to as the Dark Minimal Flavour Violation (DMFV) hypothesis. This ansatz ensures the stability of dark matter. We discuss the phenomenology of the simplest DMFV model in flavour violating observables, LHC searches, and direct dark matter detection experiments. Especially interesting is the non-trivial interplay between the constraints from the different sectors.

Monika Blanke
PoS FWNP 011 2014
PDF PostScript arXiv
TTP14-036 Selected topics on multi-loop calculations to Higgs boson properties and renormalization group functions
Luminita N. Mihaila and Matthias Steinhauser
Nucl.Part.Phys.Proc. 261-262 443-470 2015
PDF PostScript arXiv
TTP14-035 Parallel versions of FORM and more
Matthias Steinhauser, Takahiro Ueda, Jos A.M. Vermaseren
Nucl.Part.Phys.Proc. 261-262 45-57 2015
PDF PostScript arXiv

TTP14-034 Radiative generation of neutrino mixing: degenerate masses and threshold corrections

TTP14-034 Radiative generation of neutrino mixing: degenerate masses and threshold corrections

Degenerate neutrino masses are excluded by experiment. The experimentally measured mass squared differences together with the yet undetermined absolute neutrino mass scale allow for a quasi-degenerate mass spectrum. For the lightest neutrino mass larger than roughly 0.1 eV, we analyse the influence of threshold corrections at the electroweak scale. We show that typical one-loop corrections can generate the observed neutrino mixing as well as the mass differences starting from exactly degenerate masses at the tree-level. Those threshold corrections have to be explicitly flavour violating. Flavour diagonal, non-universal corrections are not sufficient to simultaneously generate the correct mixing and the mass differences. We apply the new insights to an extension of the Minimal Supersymmetric Standard Model with non-minimal flavour violation in the soft breaking terms and discuss the low-energy threshold corrections to the light neutrino mass matrix in that model.

Wolfgang Gregor Hollik
Phys.Rev. D91 033001 2015
PDF PostScript arXiv
TTP14-033 Flavour Physics Beyond the Standard Model: Recent Developments and Future Perspectives
Monika Blanke
Presented at Conference: C14-09-08
PDF PostScript arXiv
TTP14-032 Forward-backward and charge asymmetries at Tevatron and the LHC
Johann Kuehn and German Rodrigo
Presented at Conference: C14-09-08
PDF PostScript arXiv
TTP14-031 Pseudo-goldstino and electroweak gauginos via VBF processes at the LHC
Tao Liu, Lin Wang, Jin Min Yang
JHEP 1502 177 2015
PDF PostScript arXiv
TTP14-030 Standard Model beta-functions to three-loop order and vacuum stability
M. F. Zoller
Presented at Conference: C14-02-11
PDF PostScript arXiv

TTP14-029 The double mass hierarchy pattern: simultaneously understanding quark and lepton mixing

TTP14-029 The double mass hierarchy pattern: simultaneously understanding quark and lepton mixing

The charged fermion masses of the three generations exhibit the two strong hierarchies m3≫m2≫m1m3≫m2≫m1. We assume that also neutrino masses satisfy mν3>mν2>mν1mν3>mν2>mν1 and derive the consequences of the hierarchical spectra on the fermionic mixing patterns. The quark and lepton mixing matrices are built in a general framework with their matrix elements expressed in terms of the four fermion mass ratios, mu/mcmu/mc, mc/mtmc/mt, md/msmd/ms and ms/mbms/mb, and me/mμme/mμ, mμ/mτmμ/mτ, mν1/mν2mν1/mν2 and mν2/mν3mν2/mν3, for the quark and lepton sector, respectively. In this framework, we show that the resulting mixing matrices are consistent with data for both quarks and leptons, despite the large leptonic mixing angles. The minimal assumption we take is the one of hierarchical masses and minimal flavor symmetry breaking that strongly follows from phenomenology. No special structure of the mass matrices has to be assumed that cannot be motivated by this minimal assumption. This analysis allows us to predict the neutrino mass spectrum and set the mass of the lightest neutrino well below 0.01 eV. The method also gives the 1σ allowed ranges for the leptonic mixing matrix elements. Contrary to the common expectation, leptonic mixing angles are found to be determined solely by the four leptonic mass ratios without any relation to symmetry considerations as commonly used in flavor model building. Still, our formulae can be used to build up a flavor model that predicts the observed hierarchies in the masses — the mixing follows then from the procedure which is developed in this work.

Wolfgang Gregor Hollik and Ulises Jesus Saldana Salazar
Nuclear Physics B 892 364–389 2015
PDF PostScript arXiv
TTP14-028 An SU(5) x A5 Golden Ratio Flavour Model
Julia Gehrlein, Jens Oppermann, Daniela Schäfer, Martin Spinrath
Nucl.Phys. B890 539-568 2014
PDF PostScript arXiv
TTP14-027 Standard Model predictions and new physics sensitivity in B -> DD Decays
Martin Jung, Stefan Schacht
Phys.Rev. D91 3, 034027 2015
PDF PostScript arXiv
TTP14-026 Two-loop helicity amplitudes for the production of two off-shell electroweak bosons in quark-antiquark collisions
F. Caola, J. Henn, K. Melnikov, A. Smirnov, V. Smirnov
JHEP 1411 041 2014
PDF PostScript arXiv
TTP14-025 ${\cal O}(\alpha_s^2)$ corrections to the running top-Yukawa coupling and the mass of the lightest Higgs boson in the MSSM
David Kunz, Luminita Mihaila, Nikolai Zerf
JHEP 1412 136 2014
PDF PostScript arXiv Programs and Data
TTP14-024 Virtual corrections to Higgs boson pair production in the heavy top quark mass limit
Jonathan Grigo, Kirill Melnikov, Matthias Steinhauser
Nucl.Phys. B888 17-29 2014
PDF PostScript arXiv
TTP14-023 OPE of the energy-momentum tensor correlator and the gluon condensate operator in massless QCD to three-loop order
M. F. Zoller
JHEP 1410 169 2014
PDF PostScript arXiv Programs and Data
TTP14-022 Electroweak corrections to V-boson pair production at the LHC: Monte Carlo implementation and NNLO contributions
Tobias Kasprzik
PoS DIS2014 131 2014
PDF PostScript
TTP14-021 Three-loop beta function for the Higgs self-coupling
Max F. Zoller
PoS LL2014 014 2014
PDF PostScript arXiv
TTP14-020 Adequate bases of phase space master integrals for $gg\to h$ at NNLO and beyond
Maik Höschele, Jens Hoff, Takahiro Ueda
JHEP 1409 116 2014
PDF PostScript arXiv

TTP14-019 Mass-corrections to double-Higgs production & TopoID

TTP14-019 Mass-corrections to double-Higgs production & TopoID

We consider power corrections due to a finite top quark mass M_t to the production of a Higgs boson pair within the Standard Model at next-to-leading order (NLO) in QCD. Previous calculations for this process and at this precision were done in the limit of an inifinitely heavy top quark. Our results for the inclusive production cross section at NLO include terms up to O(1/M_t^12). We present the Mathematica package TopoID which for arbitrary processes aims to perform the necessary steps from Feynman diagrams to unrenormalized results expressed in terms of master integrals. We employ it for advancing in this process towards next-to-next-to-leading order (NNLO) where further automatization is needed.

Jonathan Grigo, Jens Hoff
PoS LL2014 030 2014
PDF PostScript arXiv

TTP14-018 Vacuum stability of the effective Higgs potential in the Minimal Supersymmetric Standard Model

TTP14-018 Vacuum stability of the effective Higgs potential in the Minimal Supersymmetric Standard Model

The parameters of the Higgs potential of the Minimal Supersymmetric Standard Model (MSSM) receive large radiative corrections which lift the mass of the lightest Higgs boson to the measured value of 126 GeV. Depending on the MSSM parameters, these radiative corrections may also lead to the situation that the local minimum corresponding to the electroweak vacuum state is not the global minimum of the Higgs potential. We analyze the stability of the vacuum for the case of heavy squark masses as favored by current LHC data. To this end we first consider an effective Lagrangian obtained by integrating out the heavy squarks and then study the MSSM one-loop effective potential V_eff, which comprises all higher-dimensional Higgs couplings of the effective Lagrangian. We find that only the second method gives correct results and argue that the criterion of vacuum stability should be included in phenomenological analyses of the allowed MSSM parameter space. Discussing the cases of squark masses of 1 and 2 TeV we show that the criterion of vacuum stability excludes a portion of the MSSM parameter space in which (mu tanbeta) and A_t are large.

Markus Bobrowski, Guillaume Chalons, Wolfgang G. Hollik and Ulrich Nierste
Physical Review D90 035025 2014
PDF PostScript arXiv
TTP14-017 Higher-order hadronic and heavy-lepton contributions to the anomalous magnetic moment
A. Kurz, T. Liu, P. Marquard, M. Steinhauser
PoS LL2014 051 2014
PDF PostScript arXiv
TTP14-016 $B_s\to \mu^+\mu^-$ and $\bar{B} \to X_s \gamma$ to NNLO
Matthias Steinhauser
PoS LL2014 042 2014
PDF PostScript arXiv
TTP14-015 The Physics of the B Factories
A. J. Bevan, B. Golob, Th. Mannel, S. Prell, B. D. Yabsley, et al.
Eur.Phys.J. C74 11,3026 2014
PDF PostScript arXiv

TTP14-014 Towards predictive flavour models in SUSY SU(5) GUTs with Doublet-Triplet splitting

TTP14-014 Towards predictive flavour models in SUSY SU(5) GUTs with Doublet-Triplet splitting

We discuss how the double missing partner mechanism solution to the doublet-triplet splitting problem in four-dimensional supersymmetric SU(5) Grand Unified Theories (GUTs) can be combined with predictive models for the quark-lepton Yukawa coupling ratios at the GUT scale. It is argued that towards this goal a second SU(5) breaking Higgs field in the adjoint representation is very useful and we discuss all possible renormalizable superpotentials with two adjoint Higgs fields and calculate the constraints on the GUT scale and effective triplet mass from a two-loop gauge coupling unification analysis. Two explicit flavour models with different predictions for the GUT scale Yukawa sector are presented, including shaping symmetries and a renormalizable messenger sector. Towards calculating the rates for proton decay induced by the exchange of colour triplets, the required Clebsch-Gordan coefficients for their couplings are calculated for the possible dimension five and six operators. They are provided in detailed tables in the appendix, together with additional helpful material for GUT flavour model building.

Stefan Antusch, Ivo de Medeiros Varzielas, Vinzenz Maurer, Constantin Sluka, Martin Spinrath
JHEP 1409 141 2014
PDF PostScript arXiv
TTP14-013 (Quasi-)Degeneration, Quantum Corrections and Neutrino Mixing
W. G. Hollik
Talk given at the 42th ITEP winter school, Feb 2014, Moscow, Russia
PDF PostScript arXiv
TTP14-012 An estimate of the NNLO QCD corrections to single-top production at the LHC
Mathias Brucherseifer, Fabrizio Caola, Kirill Melnikov
Phys.Lett. B736 58-63 2014
PDF PostScript arXiv
TTP14-011 On the gauge dependence of the Standard Model vacuum instability scale
Luca Di Luzio, Luminita Mihaila
JHEP 1406 079 2014
PDF PostScript arXiv
TTP14-010 Goldstini and electroweak gauginos at the LHC
Ken-ichi Hikasa, Tao Liu, Lin Wang, Jin Min Yang
JHEP 1407 065 2014
PDF PostScript arXiv
TTP14-009 Hadronic contribution to the muon anomalous magnetic moment to next-to-next-to-leading order
Alexander Kurz, Tao Liu, Peter Marquard, Matthias Steinhauser
Phys.Lett. B734 144-147 2014
PDF PostScript arXiv Programs and Data
TTP14-008 Benchmarks for Higgs pair production and heavy Higgs searches in the Two-Higgs-Doublet model of type II
Julien Baglio, Otto Eberhardt, Ulrich Nierste, and Martin Wiebusch
Phys.Rev. D90 015008 2014
PDF PostScript arXiv

TTP14-007 Quark Mass and Field Anomalous Dimensions to ${\cal O}(\alpha_s^5)$

TTP14-007 Quark Mass and Field Anomalous Dimensions to ${\cal O}(\alpha_s^5)$

We present the results of the first complete analytic calculation of the quark mass and field anomalous dimensions to ${\cal O}(\alpha_s^5)$ in QCD.

P.A. Baikov, K. G. Chetyrkin and J. H. K\“uhn
JHEP 1410 76 2014
PDF PostScript arXiv
TTP14-006 Renormalization aspects of N=1 Super Yang-Mills theory in the Wess-Zumino gauge
A.L. Capri, D.R. Granado, M.S. Guimaraes, I.F. Justo, L. Mihaila, S.P. Sorella, D. Vercauteren
Eur.Phys.J. C74 2844 2014
PDF PostScript arXiv
TTP14-005 Hyperfine splitting in positronium to O(al7 m_e): one-photon annihilation contribution
M. Baker, P. Marquard, A.A. Penin, J.H. Piclum, M. Steinhauser
Phys.Rev.Lett. 112 120407 2014
PDF PostScript arXiv
TTP14-004 Full Ο(α) electroweak radiative corrections to e+ e- -> e+ e- γ at the ILC with GRACE-Loop
P.H. Khiem, Y. Kurihara, J. Fujimoto, T. Ishikawa, T. Kaneko, K. Kato, N. Nakazawa, Y. Shimizu, T. Ueda, J.A.M. Vermaseren, Y. Yasui
Presented at Conference: C13-11-11.1
PDF PostScript arXiv
TTP14-003 The leptonic decay of the Upsilon(1S) meson at third-order in QCD
M. Beneke, Y. Kiyo, P. Marquard, A. Penin, J. Piclum, D. Seidel, M. Steinhauser
Phys.Rev.Lett. 112 151801 2014
PDF PostScript arXiv
TTP14-002 Three-loop matching of the vector current
Peter Marquard, Jan H. Piclum, Dirk Seidel, Matthias Steinhauser
Phys.Rev. D89 034027 2014
PDF PostScript arXiv Programs and Data
TTP14-001 Vector-boson pair production and electroweak corrections in HERWIG++
S. Gieseke, T. Kasprzik, J.H. Kühn
Eur.Phys.J. C74 8, 2988 2014
PDF PostScript arXiv
This website uses cookies. By using the website, you agree with storing cookies on your computer. Also you acknowledge that you have read and understand our Privacy Policy. If you do not agree leave the website.More information about cookies