Uhlemann, C. F.; Kauer, N. Narrow-width approximation accuracy. (English) Zbl 1194.81321 Nucl. Phys., B 814, No. 1-2, 195-211 (2009). Summary: A study of general properties of the narrow-width approximation (NWA) with polarization/spin decorrelation is presented. We prove for sufficiently inclusive differential rates of arbitrary resonant decay or scattering processes with an on-shell intermediate state decaying via a cubic or quartic vertex that decorrelation effects vanish and the NWA is of order \(\Gamma \). Its accuracy is then determined numerically for all resonant 3-body decays involving scalars, spin-\(\frac{1}{2}\) fermions or vector bosons. We specialize the general results to MSSM benchmark scenarios. Significant off-shell corrections can occur - similar in size to QCD corrections. We qualify the configurations in which a combined consideration is advisable. For this purpose, we also investigate process-independent methods to improve the NWA. Cited in 2 Documents MSC: 81V35 Nuclear physics 81V22 Unified quantum theories 81V05 Strong interaction, including quantum chromodynamics 81T15 Perturbative methods of renormalization applied to problems in quantum field theory 81T60 Supersymmetric field theories in quantum mechanics 81U05 \(2\)-body potential quantum scattering theory 81U35 Inelastic and multichannel quantum scattering Keywords:resonant particle production; perturbative calculations; narrow-width approximation Software:SOFTSUSY; SDECAY PDFBibTeX XMLCite \textit{C. F. Uhlemann} and \textit{N. Kauer}, Nucl. Phys., B 814, No. 1--2, 195--211 (2009; Zbl 1194.81321) Full Text: DOI arXiv References: [1] Nojiri, M. M. [2] Veltman, M. J.G., Physica, 29, 186 (1963) [3] Denner, A.; Dittmaier, S.; Roth, M.; Wackeroth, D., Nucl. Phys. B, 560, 33 (1999) [4] Denner, A.; Dittmaier, S.; Roth, M.; Wieders, L. H., Nucl. Phys. B, 724, 247 (2005) [5] Gigg, M. A.; Richardson, P. [6] Pilkuhn, H., The Interactions of Hadrons (1967), North-Holland: North-Holland Amsterdam [7] Kauer, N., Phys. Lett. B, 649, 413 (2007) [8] Dicus, D. A.; Sudarshan, E. C.G.; Tata, X., Phys. Lett. B, 154, 79 (1985) [9] Byckling, E.; Kajantie, K., Particle Kinematics (1973), John Wiley & Sons Ltd. [10] Cho, G. C.; Hagiwara, K.; Kanzaki, J.; Plehn, T.; Rainwater, D.; Stelzer, T., Phys. Rev. D, 73, 054002 (2006) [11] Muhlleitner, M.; Djouadi, A.; Mambrini, Y., Comput. Phys. Commun., 168, 46 (2005) [12] Rosiek, J. [13] C.F. Uhlemann, Narrow-width approximation in the MSSM, Diplomarbeit, Fakultät für Physik und Astronomie, Universität Würzburg, 2007, http://theorie.physik.uni-wuerzburg.de/TP2/publications/Dipl/Uhlemann-dipl.pdf; C.F. Uhlemann, Narrow-width approximation in the MSSM, Diplomarbeit, Fakultät für Physik und Astronomie, Universität Würzburg, 2007, http://theorie.physik.uni-wuerzburg.de/TP2/publications/Dipl/Uhlemann-dipl.pdf [14] Allanach, B. C., (Proceedings of APS/DPF/DPB Summer Study on the Future of Particle Physics. Proceedings of APS/DPF/DPB Summer Study on the Future of Particle Physics, Snowmass 2001 (2001), Snowmass: Snowmass Colorado, USA), 125 [15] Allanach, B. C., Comput. Phys. Commun., 143, 305 (2002) [16] Aguilar-Saavedra, J. A., Eur. Phys. J. C, 46, 43 (2006) [17] Kauer, N., JHEP, 0804, 055 (2008) This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.