Abstract
Recently, the CMS collaboration has reported their search for electroweak instanton-like processes with anomalous B + L violation assuming multi-fermion but zero-boson final states. On the other hand, many theoretical studies suggest that anomalous B + L processes may have an observably large production rate only if their final state contains a large number of electroweak gauge bosons. In this paper, we review the state-of-the-art of the predictions of electroweak instanton-induced processes and compare collider signatures of zero- and multi-boson events of anomalous B + L violation at the LHC. An upper limit on the cross-section for the multi-boson process is derived by recasting the CMS analysis.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
S.L. Adler, Axial vector vertex in spinor electrodynamics, Phys. Rev. 177 (1969) 2426 [INSPIRE].
J.S. Bell and R. Jackiw, A PCAC puzzle: π 0 → γγ in the σ model, Nuovo Cim. A 60 (1969) 47 [INSPIRE].
W.A. Bardeen, Anomalous Ward identities in spinor field theories, Phys. Rev. 184 (1969) 1848 [INSPIRE].
G. ’t Hooft, Symmetry breaking through Bell-Jackiw anomalies, Phys. Rev. Lett. 37 (1976) 8 [INSPIRE].
G. ’t Hooft, Computation of the quantum effects due to a four-dimensional pseudoparticle, Phys. Rev. D 14 (1976) 3432 [Erratum ibid. D 18 (1978) 2199] [INSPIRE].
A.A. Belavin et al., Pseudoparticle solutions of the Yang-Mills equations, Phys. Lett. B 59 (1975) 85 [INSPIRE].
I. Affleck, On constrained instantons, Nucl. Phys. B 191 (1981) 429 [INSPIRE].
V.A. Kuzmin, V.A. Rubakov and M.E. Shaposhnikov, On the anomalous electroweak baryon number nonconservation in the early universe, Phys. Lett. B 155 (1985) 36.
P.B. Arnold and L.D. McLerran, Sphalerons, small fluctuations and baryon number violation in electroweak theory, Phys. Rev. D 36 (1987) 581 [INSPIRE].
A. Ringwald, Rate of anomalous baryon and lepton number violation at finite temperature in standard electroweak theory, Phys. Lett. B 201 (1988) 510 [INSPIRE].
V.A. Rubakov and M.E. Shaposhnikov, Electroweak baryon number nonconservation in the early universe and in high-energy collisions, Usp. Fiz. Nauk 166 (1996) 493 [hep-ph/9603208] [INSPIRE].
A. Ringwald, High-energy breakdown of perturbation theory in the electroweak instanton sector, Nucl. Phys. B 330 (1990) 1 [INSPIRE].
O. Espinosa, High-energy behavior of baryon and lepton number violating scattering amplitudes and breakdown of unitarity in the standard model, Nucl. Phys. B 343 (1990) 310 [INSPIRE].
M.P. Mattis, The riddle of high-energy baryon number violation, Phys. Rept. 214 (1992) 159 [INSPIRE].
P.G. Tinyakov, Instanton like transitions in high-energy collisions, Int. J. Mod. Phys. A 8 (1993) 1823 [INSPIRE].
N.S. Manton, Topology in the Weinberg-Salam theory, Phys. Rev. D 28 (1983) 2019 [INSPIRE].
F.R. Klinkhamer and N.S. Manton, A saddle point solution in the Weinberg-Salam theory, Phys. Rev. D 30 (1984) 2212 [INSPIRE].
S. Yu. Khlebnikov, V.A. Rubakov and P.G. Tinyakov, Instanton induced cross-sections below the sphaleron, Nucl. Phys. B 350 (1991) 441 [INSPIRE].
V.V. Khoze and A. Ringwald, Total cross-section for anomalous fermion number violation via dispersion relation, Nucl. Phys. B 355 (1991) 351 [INSPIRE].
A.H. Mueller, On higher order semiclassical corrections to high-energy cross-sections in the one instanton sector, Nucl. Phys. B 364 (1991) 109 [INSPIRE].
D. Diakonov and M.V. Polyakov, Baryon number nonconservation at high-energies and instanton interactions, Nucl. Phys. B 389 (1993) 109 [INSPIRE].
I. Balitsky and A. Schafer, Valley method versus instanton induced effective Lagrangian up to (E/E sphaleron)8/3, Nucl. Phys. B 404 (1993) 639 [hep-ph/9304261] [INSPIRE].
A. Ringwald, Electroweak instantons/sphalerons at VLHC?, Phys. Lett. B 555 (2003) 227 [hep-ph/0212099] [INSPIRE].
V.I. Zakharov, Classical corrections to instanton induced interactions, Nucl. Phys. B 371 (1992) 637 [INSPIRE].
H. Aoyama and H. Goldberg, Anomalous baryon number nonconservation in pp collisions at 40 TeV, Phys. Lett. B 188 (1987) 506 [INSPIRE].
M.J. Gibbs and B.R. Webber, HERBVI: a program for simulation of baryon and lepton number violating processes, Comput. Phys. Commun. 90 (1995) 369 [hep-ph/9504232] [INSPIRE].
M.J. Gibbs, A. Ringwald, B.R. Webber and J.T. Zadrozny, Monte Carlo simulation of baryon and lepton number violating processes at high-energies, Z. Phys. C 66 (1995) 285 [hep-ph/9406266] [INSPIRE].
S. Moch, A. Ringwald and F. Schrempp, Instantons in deep inelastic scattering: The Simplest process, Nucl. Phys. B 507 (1997) 134 [hep-ph/9609445] [INSPIRE].
A. Ringwald and F. Schrempp, Instanton induced cross-sections in deep inelastic scattering, Phys. Lett. B 438 (1998) 217 [hep-ph/9806528] [INSPIRE].
A. Ringwald and F. Schrempp, QCDINS 2.0: a Monte Carlo generator for instanton induced processes in deep inelastic scattering, Comput. Phys. Commun. 132 (2000) 267 [hep-ph/9911516] [INSPIRE].
H1 collaboration, C. Adloff et al., Search for QCD instanton induced processes in deep inelastic scattering at HERA, Eur. Phys. J. C 25 (2002) 495 [hep-ex/0205078] [INSPIRE].
ZEUS collaboration, S. Chekanov et al., Search for QCD instanton induced events in deep inelastic ep scattering at HERA, Eur. Phys. J. C 34 (2004) 255 [hep-ex/0312048] [INSPIRE].
H1 collaboration, V. Andreev et al., Search for QCD instanton-induced processes at HERA in the high-Q 2 domain, Eur. Phys. J. C 76 (2016) 381 [arXiv:1603.05567] [INSPIRE].
S.H.H. Tye and S.S.C. Wong, Bloch wave function for the periodic sphaleron potential and unsuppressed baryon and lepton number violating processes, Phys. Rev. D 92 (2015) 045005 [arXiv:1505.03690] [INSPIRE].
J. Ellis and K. Sakurai, Search for sphalerons in proton-proton collisions, JHEP 04 (2016) 086 [arXiv:1601.03654] [INSPIRE].
G. Brooijmans, P. Schichtel and M. Spannowsky, Cosmic ray air showers from sphalerons, Phys. Lett. B 761 (2016) 213 [arXiv:1602.00647] [INSPIRE].
J. Ellis, K. Sakurai and M. Spannowsky, Search for sphalerons: IceCube vs. LHC, JHEP 05 (2016) 085 [arXiv:1603.06573] [INSPIRE].
M. Spannowsky and C. Tamarit, Sphalerons in composite and non-standard Higgs models, Phys. Rev. D 95 (2017) 015006 [arXiv:1611.05466] [INSPIRE].
K. Funakubo, K. Fuyuto and E. Senaha, Does a band structure affect sphaleron processes?, arXiv:1612.05431 [INSPIRE].
D.G. Cerdeño, P. Reimitz, K. Sakurai and C. Tamarit, B + L violation at colliders and new physics, JHEP 04 (2018) 076 [arXiv:1801.03492] [INSPIRE].
Y. Jho and S.C. Park, Constraining new physics with high multiplicity: I. Ultra-high energy cosmic rays on air-shower detector arrays, arXiv:1806.03063 [INSPIRE].
CMS collaboration, Search for black holes and sphalerons in high-multiplicity final states in proton-proton collisions at \( \sqrt{s}=13 \) TeV, arXiv:1805.06013 [INSPIRE].
C. Bravo and J. Hauser, BaryoGEN, a Monte Carlo generator for sphaleron-like transitions in proton-proton collisions, arXiv:1805.02786 [INSPIRE].
A. Ringwald, F. Schrempp and C. Wetterich, Phenomenology of geometrical flavor interactions at TeV energies, Nucl. Phys. B 365 (1991) 3 [INSPIRE].
T. Sjöstrand et al., An introduction to PYTHIA 8.2, Comput. Phys. Commun. 191 (2015) 159 [arXiv:1410.3012] [INSPIRE].
G. Corcella et al., HERWIG 6: an event generator for hadron emission reactions with interfering gluons (including supersymmetric processes), JHEP 01 (2001) 010 [hep-ph/0011363] [INSPIRE].
G. Corcella et al., HERWIG 6.5 release note, hep-ph/0210213 [INSPIRE].
DELPHES 3 collaboration, J. de Favereau et al., DELPHES 3, a modular framework for fast simulation of a generic collider experiment, JHEP 02 (2014) 057 [arXiv:1307.6346] [INSPIRE].
H.-L. Lai et al., New parton distributions for collider physics, Phys. Rev. D 82 (2010) 074024 [arXiv:1007.2241] [INSPIRE].
Open Access
This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.
Author information
Authors and Affiliations
Corresponding author
Additional information
ArXiv ePrint: 1809.10833
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.
The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.
To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/.
About this article
Cite this article
Ringwald, A., Sakurai, K. & Webber, B.R. Limits on electroweak instanton-induced processes with multiple boson production. J. High Energ. Phys. 2018, 105 (2018). https://doi.org/10.1007/JHEP11(2018)105
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/JHEP11(2018)105