# Rare hyperon decays with missing energy

- 21 Downloads

## Abstract

We explore the strangeness-changing decays of the lightest hyperons into another baryon plus missing energy within and beyond the standard model (SM). In the SM these processes arise from the loop-induced quark transition \( s\to d\nu \overline{\nu} \) and their branching fractions are estimated to be less than 10^{−11}. In the presence of new physics (NP) the rates of these hyperon decays with missing energy could increase significantly with respect to the SM expectations because of modifications to the SM process or contributions from additional modes with new invisible particles. Adopting a model-independent approach and taking into account constraints from the kaon sector, we find that the current data on \( K\to \pi \nu \overline{\nu} \) do not permit sizable NP impact on the hyperon decays via underlying operators having mainly parity-even quark parts. In contrast, NP operators with primarily parity-odd quark parts are much less restricted by the existing bounds on *K* → invisible and \( K\to \pi \pi \nu \overline{\nu} \) and consequently could produce substantially amplifying effects on the hyperon modes. Their NP-enhanced branching fractions could reach levels potentially observable in the ongoing BESIII experiment.

## Keywords

Beyond Standard Model Effective Field Theories Kaon Physics Chiral Lagrangians## Notes

### **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.

## References

- [1]G. Buchalla, A.J. Buras and M.E. Lautenbacher,
*Weak decays beyond leading logarithms*,*Rev. Mod. Phys.***68**(1996) 1125 [hep-ph/9512380] [INSPIRE]. - [2]W.J. Marciano and Z. Parsa,
*Rare kaon decays with*“*missing energy*”,*Phys. Rev.***D 53**(1996) R1.Google Scholar - [3]Y. Grossman and Y. Nir,
*K*(*L*) →*π*^{0}*neutrino anti-neutrino beyond the standard model*,*Phys. Lett.***B 398**(1997) 163 [hep-ph/9701313] [INSPIRE]. - [4]A.J. Buras, F. Schwab and S. Uhlig,
*Waiting for precise measurements of*\( {K}^{+}\to {\pi}^{+}\nu \overline{\nu} \)*and*\( {K}_L\to {\pi}^0\nu \overline{\nu} \),*Rev. Mod. Phys.***80**(2008) 965 [hep-ph/0405132] [INSPIRE]. - [5]C.-J. Lee and J. Tandean,
*Minimal lepton flavor violation implications of the b*→*s anomalies*,*JHEP***08**(2015) 123 [arXiv:1505.04692] [INSPIRE]. - [6]K. Fuyuto, W.-S. Hou and M. Kohda,
*Z*^{′}*-induced FCNC decays of top, beauty and strange quarks*,*Phys. Rev.***D 93**(2016) 054021 [arXiv:1512.09026] [INSPIRE]. - [7]H.-B. Li,
*Prospects for rare and forbidden hyperon decays at BESIII*,*Front. Phys. (Beijing)***12**(2017) 121301 [arXiv:1612.01775] [INSPIRE].CrossRefGoogle Scholar - [8]C.-W. Chiang, X.-G. He, J. Tandean and X.-B. Yuan, \( {R}_{K^{\left(\ast \right)}} \)
*and related*\( b\to s\ell \overline{\ell} \)*anomalies in minimal flavor violation framework with Z*^{′}*boson*,*Phys. Rev.***D 96**(2017) 115022 [arXiv:1706.02696] [INSPIRE]. - [9]X.-H. Hu and Z.-X. Zhao,
*Study of*\( s\to d\nu \overline{\nu} \)*rare hyperon decays within the standard model and new physics*, arXiv:1811.01478 [INSPIRE]. - [10]X.-G. He and G. Valencia, \( {K}^{+}\to {\pi}^{+}\nu \overline{\nu} \)
*and FCNC from non-universal Z*^{′}*bosons*,*Phys. Rev.***D 70**(2004) 053003 [hep-ph/0404229] [INSPIRE]. - [11]C. Bird, R.V. Kowalewski and M. Pospelov,
*Dark matter pair-production in b*→*s transitions*,*Mod. Phys. Lett.***A 21**(2006) 457 [hep-ph/0601090] [INSPIRE]. - [12]X.-G. He, S.-Y. Ho, J. Tandean and H.-C. Tsai,
*Scalar dark matter and standard model with four generations*,*Phys. Rev.***D 82**(2010) 035016 [arXiv:1004.3464] [INSPIRE]. - [13]J.F. Kamenik and C. Smith,
*FCNC portals to the dark sector*,*JHEP***03**(2012) 090 [arXiv:1111.6402] [INSPIRE].ADSCrossRefzbMATHGoogle Scholar - [14]M.J. Dolan, F. Kahlhoefer, C. McCabe and K. Schmidt-Hoberg,
*A taste of dark matter: Flavour constraints on pseudoscalar mediators*,*JHEP***03**(2015) 171 [*Erratum ibid.***07**(2015) 103] [arXiv:1412.5174] [INSPIRE]. - [15]S.N. Gninenko and N.V. Krasnikov,
*Invisible K*_{L}*decays as a probe of new physics*,*Phys. Rev.***D 92**(2015) 034009 [arXiv:1503.01595] [INSPIRE]. - [16]A. Abada et al.,
*Sterile neutrinos facing kaon physics experiments*,*Phys. Rev.***D 95**(2017) 075023 [arXiv:1612.04737] [INSPIRE]. - [17]X.-G. He, G. Valencia and K. Wong,
*Constraints on new physics from*\( K\to \pi \nu \overline{\nu} \),*Eur. Phys. J.***C 78**(2018) 472 [arXiv:1804.07449] [INSPIRE]. - [18]D. Barducci, M. Fabbrichesi and E. Gabrielli,
*Neutral hadrons disappearing into the darkness*,*Phys. Rev.***D 98**(2018) 035049 [arXiv:1806.05678] [INSPIRE]. - [19]S. Matsumoto, Y.-L.S. Tsai and P.-Y. Tseng,
*Light fermionic WIMP dark matter with light scalar mediator*, arXiv:1811.03292 [INSPIRE]. - [20]NA62 collaboration,
*First search for*\( {K}^{+}\to {\pi}^{+}\nu \overline{\nu} \)*using the decay-in-flight technique*,*Phys. Lett.***B 791**(2019) 156 [arXiv:1811.08508] [INSPIRE]. - [21]KOTO collaboration,
*Search for the*\( {K}_L\to {\pi}^0\nu \overline{\nu} \)*and K*_{L}→*π*^{0}*X*^{0}*decays at the J-PARC KOTO experiment*,*Phys. Rev. Lett.***122**(2019) 021802 [arXiv:1810.09655] [INSPIRE]. - [22]Particle Data Group collaboration,
*Review of particle physics*,*Phys. Rev.***D 98**(2018) 030001.Google Scholar - [23]M. Arteaga, E. Bertuzzo, C. Caniu Barros and Z. Tabrizi,
*Operators from flavored dark sectors running to low energy*,*Phys. Rev.***D 99**(2019) 035022 [arXiv:1810.04747] [INSPIRE]. - [24]P. Langacker,
*The physics of heavy Z*^{′}*gauge bosons*,*Rev. Mod. Phys.***81**(2009) 1199 [arXiv:0801.1345] [INSPIRE]. - [25]A. Ismail, W.-Y. Keung, K.-H. Tsao and J. Unwin,
*Axial vector Z*^{′}*and anomaly cancellation*,*Nucl. Phys.***B 918**(2017) 220 [arXiv:1609.02188] [INSPIRE]. - [26]A. Alves et al.,
*Augury of darkness: the low-mass dark Z*^{′}*portal*,*JHEP***04**(2017) 164 [arXiv:1612.07282] [INSPIRE]. - [27]Bristol-Geneva-Heidelberg-Orsay-Rutherford-Strasbourg collaboration,
*Measurements of Hyperon Semileptonic Decays at the CERN super proton synchrotron. 1. The*Σ^{−}→ Λ*e*^{−}*anti-neutrino decay mode*,*Z. Phys.***C 12**(1982) 307 [INSPIRE]. - [28]S.Y. Hsueh et al.,
*A high precision measurement of polarized σ-β decay*,*Phys. Rev.***D 38**(1988) 2056 [INSPIRE]. - [29]J. Dworkin et al.,
*High statistics measurement of g*(*a*)*/g*(*v*)*in*\( \Lambda\ \to p+{e}^{-}+\overline{\nu} \),*Phys. Rev.***D 41**(1990) 780 [INSPIRE]. - [30]NA48/I collaboration,
*Measurement of the branching ratios of the decays*\( {\Xi}_0\to {\Sigma}^{+}{e}^{-}{\overline{\nu}}_e \)*and*Ξ_{0}→ Σ^{+}*e*^{+}*ν*_{e},*Phys. Lett.***B 645**(2007) 36 [hep-ex/0612043] [INSPIRE]. - [31]J. Charles et al.,
*Current status of the standard model CKM fit and constraints on*Δ*F*= 2*new physics*,*Phys. Rev.***D 91**(2015) 073007 [arXiv:1501.05013] [INSPIRE]. - [32]A.J. Buras, D. Buttazzo, J. Girrbach-Noe and R. Knegjens, \( {K}^{+}\to {\pi}^{+}\nu \overline{\nu} \)
*and*\( {K}_L\to {\pi}^0\nu \overline{\nu} \)*in the standard model: status and perspectives*,*JHEP***11**(2015) 033 [arXiv:1503.02693] [INSPIRE]. - [33]S.N. Gninenko,
*Search for invisible decays of π*^{0}*, η, η*^{′}*, K*_{S}*and K*_{L}*: a probe of new physics and tests using the Bell-Steinberger relation*,*Phys. Rev.***D 91**(2015) 015004 [arXiv:1409.2288] [INSPIRE]. - [34]C. Bobeth and A.J. Buras,
*Leptoquarks meet*ε^{′}*/*ε*and rare Kaon processes*,*JHEP***02**(2018) 101 [arXiv:1712.01295] [INSPIRE]. - [35]L.S. Littenberg and G. Valencia,
*The decays K*→ ππ*neutrino anti-neutrino within the standard model*,*Phys. Lett.***B 385**(1996) 379 [hep-ph/9512413] [INSPIRE]. - [36]C.-W. Chiang and F.J. Gilman, \( K\left(L,\ S\right)\to \pi \pi \nu \overline{\nu} \)
*decays within and beyond the standard model*,*Phys. Rev.***D 62**(2000) 094026 [hep-ph/0007063] [INSPIRE]. - [37]E787 collaboration,
*Search for the decay*\( {K}^{+}\to {\pi}^{+}{\pi}^0\overline{\nu} \) ν,*Phys. Rev.***D 63**(2001) 032004 [hep-ex/0009055] [INSPIRE]. - [38]E391a collaboration,
*Study of the*\( {K}_L^0\to {\pi}^0{\pi}^0\nu \overline{\nu} \)*decay*,*Phys. Rev.***D 84**(2011) 052009 [arXiv:1106.3404] [INSPIRE]. - [39]J. Gasser and H. Leutwyler,
*Chiral perturbation theory to one loop*,*Annals Phys.***158**(1984) 142 [INSPIRE].ADSMathSciNetCrossRefGoogle Scholar - [40]J. Bijnens, H. Sonoda and M.B. Wise,
*On the validity of chiral perturbation theory for weak hyperon decays*,*Nucl. Phys.***B 261**(1985) 185 [INSPIRE]. - [41]E.E. Jenkins and A.V. Manohar,
*Chiral corrections to the baryon axial currents*,*Phys. Lett.***B 259**(1991) 353 [INSPIRE]. - [42]X.-G. He, J. Tandean and G. Valencia,
*Implications of a new particle from the hyperCP data on*Σ^{+}→*pμ*^{+}*μ*^{−},*Phys. Lett.***B 631**(2005) 100 [hep-ph/0509041] [INSPIRE].