Abstract.
Processes of the form pp → anything → X i X j → \(x\bar{x}\) + \(y\bar{y}\) + notE are studied via a technique that may be viewed as an adaptation of time-honoured Dalitz plot analyses. X i and X j are new heavy states (with i, j =1, . . .,n), which may be identical or distinct; and \(x\bar{x}\) and \(y\bar{y}\) are necessarily distinct standard model (SM) fermion pairs whose invariant masses can be measured. A Dalitz-like plot of said invariant masses, \(M(x\bar{x})\) versus \(M(y\bar{y})\), exhibits a topology connected to the masses and specific decay chains of X i and X j . Aside from relatively minor details, observed patterns consist of a collection of box and wedge shapes. This collection is model-dependent: comparison of the observed pattern to the possibilities for a specific model yields information on which new particle pair combinations are actually being produced, information beyond that extractable from conventional one-dimensional invariant mass distributions. The technique is illustrated via application to the minimal supersymmetric standard model (MSSM) process pp → \( \tilde{g}\tilde{g},\tilde{g}\tilde{q},\tilde{q}\tilde{q} \to \widetilde{\chi}_i^0 \widetilde{\chi}_j^0\) → e + e - + μ + μ - notE. Here the heavy states are neutralinos \(\widetilde{\chi}_i^0\) (i = 2,3,4) - note that \(\widetilde{\chi}_1^0\) is excluded - which are produced in gluino/squark (\(\tilde{g}\)/\(\tilde{q}\)) cascade decay chains. Even with fairly modest expectations for the LHC performance during the first few years, this method still provides substantial insight into the neutralino mass spectrum and couplings if gluino/squark masses are relatively low (≃ 400 GeV).
Similar content being viewed by others
References
For reviews of the MSSM and SUSY, see Perspectives on Supersymmetry, edited by G. Kane (World Scientific, Singapore 1998); M. Drees, S.P. Martin, in Electroweak Symmetry Breaking and New Physics at the TeV Scale, edited by T.L. Barklow, S. Dawson, H.E. Haber, J.L. Siegrist, pp. 146-215 (World Scientific, Singapore 1996) (hep-ph/9504324); H. Baer et al., ibid., pages 216-286 (hep-ph/9503479); H.E. Haber, Nucl. Phys. Proc. Suppl. 62, 469 (1998) (hep-ph/9709450)
H.-C. Cheng, I. Low, JHEP 0309, 051 (2003); 0408, 061 (2004); I. Low, JHEP 0410, 067 (2004); J. Hubisz, P. Meade, Phys. Rev. D 71, 035016 (2005)
H.-C. Cheng, K.T. Matchev, M. Schmaltz, Phys. Rev. D 66, 056006 (2002)
The original Dalitz plot papers are R.H. Dalitz, Phil. Mag. 44, 1068 (1953); E. Fabri, Nuovo Cimento 1, 479 (1954); for examples of resonance-hunting using Dalitz plots see, for example, J. Shafer, J. Murray, D. Huwe, Phys. Rev. Lett. 10, 176 (1963); M. Ferro Luzzi et al., Nuovo Cimento 36, 1101 (1965)
K.A. Assamagan et al., hep-ph/0406152
W. Beenakker, R. Hopker, M. Spira, P.M. Zerwas, Nucl. Phys. B 492, 51 (1997)
M. Bisset, N. Kersting, J. Li, F. Moortgat, S. Moretti, in preparation
H. Baer, C-H. Chen, F. Paige, X. Tata, Phys. Rev. D 53, 6241 (1996)
F.E. Paige, hep-ph/9609373; I. Hinchliffe, F.E. Paige, M.D. Shapiro, J. Söderqvist, W. Yao, Phys. Rev. D 55, 5520 (1997)
H. Bachacou, I. Hinchliffe, F.E. Paige, Phys. Rev. D 62, 015009 (2000)
J.G. Branson, D. Denegri, I. Hinchliffe, F. Gianotti, F.E. Paige, P. Sphicas, hep-ph/9609373
D. Denegri, W. Majerotto, L. Rurua, Phys. Rev. D 58, 095010 (1998); 60, 035008 (1999)
H. Baer, C-H. Chen, M. Drees, F. Paige, X. Tata, Phys. Rev. D 59, 055014 (1999)
H. Baer, M. Bisset, D. Dicus, C. Kao, X. Tata, Phys. Rev. D 47, 1062 (1993); H. Baer, M. Bisset, C. Kao, X. Tata, Phys. Rev. D 50, 316 (1994)
F. Moortgat, S. Abdullin, D. Denegri, hep-ph/0112046
H. Baer, X. Tata, Phys. Rev. D 47, 2739 (1993)
LEP SUSY Working Group web page, http://www.cern.ch/LEPSUSY/
G. Corcella et al., JHEP 0101, 010 (2001), hep-ph/0210213; S. Moretti, K. Odagiri, P. Richardson, M.H. Seymour, B.R. Webber, JHEP 0204, 028 (2002)
J. Pumplin et al. (CTEQ Collaboration) (CTEQ6), JHEP 0207, 012 (2002); 0310, 046 (2003); H.L. Lai et al. (CTEQ Collaboration) (CTEQ5), Eur. Phys. J. C 12, 375 (2000)
H. Baer, F.E. Paige, S.D. Protopopescu, X. Tata, hep-ph/0001086; hep-ph/0312045
W.W. Armstrong et al. (ATLAS Collaboration), Technical Design Report, CERN/LHCC/94-43, December 1994
K. Kawagoe, M.M. Nojiri, G. Polesello, Phys. Rev. D 71, 035008 (2005); M.M. Nojiri, G. Polesello, D.R. Tovey, hep-ph/0312317; M.M. Nojiri, hep-ph/0411127
Author information
Authors and Affiliations
Corresponding author
Additional information
Arrival of the final proofs: 29 November 2005
Rights and permissions
About this article
Cite this article
Bisset, M., Kersting, N., Li, J. et al. Pair-produced heavy particle topologies: MSSM neutralino properties at the LHC from gluino/squark cascade decays. Eur. Phys. J. C 45, 477–492 (2006). https://doi.org/10.1140/epjc/s2005-02433-4
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1140/epjc/s2005-02433-4