Logo der Universität Hamburg

The SFB 676 has been funded by the DFG from 2006 to 2018. The project was completed with a special colloquium in June 2018. A book with the scientific results of the SFB 676 has been published in September 2018.

J. Haller and M. Grefe (eds.), “Particles, Strings and the Early Universe: The Structure of Matter and Space-Time,” Hamburg (2018), DOI: 10.3204/PUBDB-2018-00782.

Many research directions developed within the SFB 676 will be continued within the Cluster of Excellence "Quantum Universe" starting 1 January 2019.

B4 – Unstable Quantum Fields and Higgs Vacuum



Project Leaders

Bernd Kniehl (e-mail | group homepage)


Abstract

In general, mixing and instability of elementary particles concur in nature. The central goal is to construct a general renormalization scheme that rigorously incorporates both aspects for fermionic and bosonic degrees of freedom, so that the renormalized parameters are gauge independent and the mixing matrices retain their tree-level properties, e.g. unitarity, texture zeros, etc. The phenomenological implications of this new concept for present and future precision tests of the standard model, its minimal supersymmetric extension, and alternative new-physics scenarios are to be analyzed quantitatively.


Researchers

Anne Ernst

Mikhail Kalmykov

Gustav Kramer

Andrey Pikelner

Andreas Ringwald

Oleg Tarasov

Oleg Veretin


Former members

Andrea Almasy

Malgorzata Awramik

Isabella Bierenbaum

Mathias Butenschön

Elena Scherbakova


Publications


Get these publications as bibtex-file


"On the b-quark running mass in QCD and the SM"
Bednyakov, A. V. and Kniehl, B. A. and Pikelner, A. F. and Veretin, O. L.
Nucl. Phys. B916, 463-483 (2017)
doi: 10.1016/j.nuclphysb.2017.01.004
eprint: 1612.00660 [hep-ph]

"An advanced precision analysis of the SM vacuum stability"
Bednyakov, A. V.
Proceedings, International Session-Conference of the SNP of PSD RAS "Physics of Fundamental Interactions": Dubna, Russia, April 12-15, 2016, Phys. Part. Nucl. (2017)
doi: 10.1134/S1063779617050057
eprint: 1609.02503 [hep-ph]

"On the four-loop strong coupling beta-function in the SM"
Bednyakov, A. V. and Pikelner, A. F.
Proceedings, 19th International Seminar on High Energy Physics Quarks 2016: Pushkin, Russia, May 29-June 4, 2016, EPJ Web Conf. (2016)
doi: 10.1051/epjconf/201612504008
eprint: 1609.02597 [hep-ph]

"mr: a C++ library for the matching and running of the Standard Model parameters"
Kniehl, Bernd A. and Pikelner, Andrey F. and Veretin, Oleg L.
Comput. Phys. Commun. 206, 84-96 (2016)
doi: 10.1016/j.cpc.2016.04.017
eprint: 1601.08143 [hep-ph]

"Four-loop strong coupling beta-function in the Standard Model"
Bednyakov, A. V. and Pikelner, A. F.
Phys. Lett. B762, 151-156 (2016)
doi: 10.1016/j.physletb.2016.09.007
eprint: 1508.02680 [hep-ph]

"Stability of the Electroweak Vacuum: Gauge Independence and Advanced Precision"
Bednyakov, A. V. and Kniehl, B. A. and Pikelner, A. F. and Veretin, O. L.
Phys. Rev. Lett. 115, 201802 (2015)
doi: 10.1103/PhysRevLett.115.201802
eprint: 1507.08833 [hep-ph]

"Two-loop electroweak threshold corrections in the Standard Model"
Kniehl, Bernd A. and Pikelner, Andrey F. and Veretin, Oleg L.
Nucl.Phys. B896, 19-51 (2015)
doi: 10.1016/j.nuclphysb.2015.04.010
eprint: 1503.02138 [hep-ph]

"Self-consistence of the Standard Model via the renormalization group analysis"
Jegerlehner, Fred and Kalmykov, Mikhail \relax Yu. and Kniehl, Bernd A.
Proceedings, 16th International workshop on Advanced Computing and Analysis Techniques in physics ACAT 14: Prague, Czech Republic, September 1-5, 2014, J. Phys. Conf. Ser. (2015)
doi: 10.1088/1742-6596/608/1/012074
eprint: 1412.4215 [hep-ph]

"Considerations concerning the generalization of the Dirac equations to unstable fermions"
Kniehl, Bernd A. and Sirlin, Alberto
Phys.Rev. D90, 077901 (2014)
doi: 10.1103/PhysRevD.90.077901
eprint: 1409.5869 [hep-ph]

"Propagator mixing renormalization for Majorana fermions"
Kniehl, Bernd A.
Phys.Rev. D89, 116010 (2014)
doi: 10.1103/PhysRevD.89.116010
eprint: 1404.5908 [hep-th]

"Two-loop electroweak threshold corrections to the bottom and top Yukawa couplings"
Kniehl, Bernd A. and Veretin, Oleg L.
Nucl.Phys. B885, 459-480 (2014)
doi: 10.1016/j.nuclphysb.2015.02.012, 10.1016/j.nuclphysb.2014.05.029
eprint: 1401.1844 [hep-ph]

"All-Order Renormalization of the Propagator Matrix for Fermionic Systems with Flavor Mixing"
Kniehl, Bernd A.
Phys.Rev.Lett. 112, 071603 (2014)
doi: 10.1103/PhysRevLett.112.071603
eprint: 1308.3140 [hep-ph]

"All-order renormalization of propagator matrix for unstable Dirac fermions"
Kniehl, Bernd A.
Phys.Rev. D89, 096005 (2014)
doi: 10.1103/PhysRevD.89.096005

"About the EW contribution to the relation between pole and MS-masses of the top-quark in the Standard Model"
Jegerlehner, Fred and Kalmykov, Mikhail Yu. and Kniehl, Bernd A.
PoS DIS2013, 190 (2013)
eprint: 1307.4226

"On the difference between the pole and the \overline\mathrmMS masses of the top quark at the electroweak scale"
Jegerlehner, Fred and Kalmykov, Mikhail Yu. and Kniehl, Bernd A.
Phys.Lett. B722, 123-129 (2013)
doi: 10.1016/j.physletb.2013.04.012
eprint: 1212.4319 [hep-ph]

"Higgs Boson Mass and New Physics"
Bezrukov, Fedor and Kalmykov, Mikhail Yu. and Kniehl, Bernd A. and Shaposhnikov, Mikhail
JHEP 1210, 140 (2012)
doi: 10.1007/JHEP10(2012)140
eprint: 1205.2893 [hep-ph]

"Renormalization in general theories with inter-generation mixing"
Kniehl, Bernd A. and Sirlin, Alberto
Phys.Rev. D85, 036007 (2012)
doi: 10.1103/PhysRevD.85.036007
eprint: 1201.4333 [hep-ph]

"Quark mixing renormalization effects in the determination of |V_tq|"
Almasy, Andrea A. and Kniehl, Bernd A. and Sirlin, Alberto
Phys.Rev. D83, 096004 (2011)
doi: 10.1103/PhysRevD.83.096004
eprint: 1101.5758 [hep-ph]

"Novel formulations of CKM matrix renormalization"
Kniehl, Bernd A. and Sirlin, Alberto
AIP Conf.Proc. 1182, 327-330 (2009)
doi: 10.1063/1.3293809
eprint: 0906.2670 [hep-ph]

"On-shell renormalization of the mixing matrices in Majorana neutrino theories"
Almasy, Andrea A. and Kniehl, Bernd A. and Sirlin, Alberto
Nucl. Phys. B818, 115-134 (2009)
doi: 10.1016/j.nuclphysb.2009.03.025
eprint: 0902.3793 [hep-ph]

"A Novel Formulation of Cabibbo-Kobayashi-Maskawa Matrix Renormalization"
Kniehl, Bernd A. and Sirlin, Alberto
Phys. Lett. B673, 208-210 (2009)
doi: 10.1016/j.physletb.2009.02.024
eprint: 0901.0114 [hep-ph]

"Quark-mixing renormalization effects on the W-boson partial decay widths"
Almasy, A. A. and Kniehl, B. A. and Sirlin, A.
Phys. Rev. D79, 076007 (2009)
doi: 10.1103/PhysRevD.79.076007
eprint: 0811.0355 [hep-ph]

"Pole Mass, Width, and Propagators of Unstable Fermions"
Kniehl, Bernd A. and Sirlin, Alberto
Phys. Rev. D77, 116012 (2008)
doi: 10.1103/PhysRevD.77.116012
eprint: 0801.0669 [hep-th]

"Simple on-shell renormalization framework for the Cabibbo- Kobayashi-Maskawa matrix"
Kniehl, Bernd A. and Sirlin, Alberto
Phys. Rev. D74, 116003 (2006)
doi: 10.1103/PhysRevD.74.116003
eprint: hep-th/0612033

"Simple Approach to Renormalize the Cabibbo-Kobayashi- Maskawa Matrix"
Kniehl, Bernd A. and Sirlin, Alberto
Phys. Rev. Lett. 97, 221801 (2006)
doi: 10.1103/PhysRevLett.97.221801
eprint: hep-ph/0608306


Theses


Master thesis: "Towards mixing renormalization at two loops via the Nielsen identities"
Ernst, Anne
Universität Hamburg ({2015})

PhD thesis: "Photoproduction of the J/psi meson at HERA at next-to-leading order within the framework of nonrelativistic QCD"
Butenschön, Mathias
Universtät Hamburg (2009)
[ link ]

Impressum  | last modified 10 Sep 2018