Search for heavy resonances in the W/Z-tagged dijet mass spectrum in pp collisions at 7 TeV

A search has been made for massive resonances decaying into a quark and a vector boson, qW or qZ, or a pair of vector bosons, WW, WZ, or ZZ, where each vector boson decays to hadronic final states. This search is based on a data sample corresponding to an integrated luminosity of 5.0 fb−15.0 fb−1 of proton–proton collisions collected in the CMS experiment at the LHC in 2011 at a center-of-mass energy of 7 TeV. For sufficiently heavy resonances the decay products of each vector boson are merged into a single jet, and the event effectively has a dijet topology. The background from QCD dijet events is reduced using recently developed techniques that resolve jet substructure. A 95% CL lower limit is set on the mass of excited quark resonances decaying into qW (qZ) at 2.38 TeV (2.15 TeV) and upper limits are set on the cross section for resonances decaying to qW, qZ, WW, WZ, or ZZ final states.

[1]  M. Gigg,et al.  Herwig++ physics and manual , 2008, 0803.0883.

[2]  L. Anchordoqui,et al.  Jet signals for low mass strings at the large hadron collider. , 2007, Physical review letters.

[3]  J. Huston,et al.  New generation of parton distributions with uncertainties from global QCD analysis , 2002, hep-ph/0201195.

[4]  J. T. Childers,et al.  ATLAS search for new phenomena in dijet mass and angular distributions using pp collisions at √s=7 TeV , 2012, 1210.1718.

[5]  R. G. Roberts,et al.  MRST2001: partons and $\alpha_S$ from precise deep inelastic scattering and Tevatron jet data , 2001, hep-ph/0110215.

[6]  Serguei Chatrchyan,et al.  Measurement of the underlying event activity at the LHC with sqrt(s)=7 TeV and comparison with sqrt(s) = 0.9 TeV , 2011 .

[7]  E. Eichten,et al.  Super Collider Physics , 1984 .

[8]  Search for Randall-Sundrum Graviton Excitations in the CMS Experiment , 2002, hep-ex/0207061.

[9]  M. Cacciari,et al.  FastJet user manual , 2011, 1111.6097.

[10]  João Paulo Teixeira,et al.  The CMS experiment at the CERN LHC , 2008 .

[11]  J. Hewett,et al.  Low-energy phenomenology of superstring-inspired E6 models , 1989 .

[12]  Suzan Basegmez,et al.  Search for a narrow spin-2 resonance decaying to a pair of Z vector bosons in the semileptonic final state , 2012, 1209.3807.

[13]  Cen,et al.  Search for excited quarks in pp-bar collisions at sqrt s =1.8 TeV. , 1994, Physical review letters.

[14]  M. Cacciari,et al.  Pileup subtraction using jet areas , 2007, 0707.1378.

[15]  Serguei Chatrchyan,et al.  Search for resonances in the dijet mass spectrum from 7 TeV pp collisions at CMS , 2011 .

[16]  V. M. Ghete,et al.  Determination of jet energy calibration and transverse momentum resolution in CMS , 2011 .

[17]  A. Soni,et al.  Towards establishing the spin of warped gravitons , 2008, 0806.3427.

[18]  S. Moretti,et al.  Better jet clustering algorithms , 1997, hep-ph/9707323.

[19]  L. Randall,et al.  An Alternative to compactification , 1999, hep-th/9906064.

[20]  David Atwood,et al.  Search for RS gravitons via WLWL decays , 2007, 0711.3175.

[21]  K. Agashe,et al.  Warped gravitons at the CERN LHC and beyond , 2007, hep-ph/0701186.

[22]  G. Aad.  Search for resonant $WZ$ production in the $WZ \to \ell \nu \ell^\prime\ell^\prime$ channel in $\sqrt{s}=7$ TeV $pp$ collisions with the ATLAS detector , 2012 .

[23]  S. D. Ellis,et al.  Techniques for improved heavy particle searches with jet substructure , 2009, 0903.5081.

[24]  M. Cacciari,et al.  The anti-$k_t$ jet clustering algorithm , 2008, 0802.1189.

[25]  M. Z. Mehta,et al.  Search for anomalous $ t\overline t $ production in the highly-boosted all-hadronic final state , 2012 .

[26]  Tim Stelzer,et al.  MadGraph/MadEvent v4: The New Web Generation , 2007, 0706.2334.

[27]  M. L. Ferrer,et al.  Search for a heavy gauge boson decaying to a charged lepton and a neutrino in 1 fb-1 of pp collisions at √s = 7 TeV using the ATLAS detector , 2011 .

[28]  M. Cacciari,et al.  Dispelling the N3 myth for the kt jet-finder , 2005, hep-ph/0512210.

[29]  E. Simmons.  Coloron Phenomenology , 1996, hep-ph/9608269.

[30]  M. Peskin,et al.  TeV strings and collider probes of large extra dimensions , 2000, hep-ph/0001166.

[31]  F. Taylor.  Search for new particles decaying to ZZ using final states with leptons and jets with the ATLAS detector in √s = 7 TeV proton–proton collisions , 2012 .

[32]  L. Randall,et al.  A Large mass hierarchy from a small extra dimension , 1999, hep-ph/9905221.

[33]  Zerwas,et al.  Excited-quark and -lepton production at hadron colliders. , 1990, Physical review. D, Particles and fields.

[34]  G. Bruno,et al.  Search for anomalous production of highly boosted Z bosons decaying to mu(+)mu(-) in proton-proton collisions at root s=7 TeV , 2013 .

[35]  Ad Feelders,et al.  Statistical concepts , 2003 .

[36]  Chuan Yi Tang,et al.  A 2.|E|-Bit Distributed Algorithm for the Directed Euler Trail Problem , 1993, Inf. Process. Lett..

[37]  R. Field.  Early LHC Underlying Event Data - Findings and Surprises , 2010, 1010.3558.

[38]  M. Cacciari,et al.  The Catchment Area of Jets , 2008, 0802.1188.

[39]  T. Tuuva,et al.  Search for leptonic decays of W′ bosons in pp collisions at $ \sqrt {s} = {7} $ TeV , 2012 .

[40]  I. Hinchliffe,et al.  EXCITED QUARK PRODUCTION AT HADRON COLLIDERS , 1987 .

[41]  T. Wengler,et al.  Hadronization Corrections to Jet Cross Sections in Deep-Inelastic Scattering , 1998, hep-ph/9907280.

[42]  R. Frühwirth,et al.  Search for narrow resonances and quantum black holes in inclusive and b-tagged dijet mass spectra from pp collisions at $ \sqrt{s}=7 $ TeV , 2013 .

[43]  M. Dorigo,et al.  Search for high-mass resonances decaying into ZZ in pp̄ collisions at √s=1.96TeV , 2011, 1111.3432.

[44]  Paul H. Frampton,et al.  Chiral color: An alternative to the standard model☆ , 1987 .

[45]  S. D. Ellis,et al.  Recombination algorithms and jet substructure: Pruning as a tool for heavy particle searches , 2009, 0912.0033.

[46]  Andrea Benaglia,et al.  Search for a $W^\prime$ or Techni-$\rho$ Decaying into $WZ$ in $pp$ Collisions at $\sqrt{s}=7$ TeV , 2012 .

[47]  S. Mrenna,et al.  Pythia 6.3 physics and manual , 2003, hep-ph/0308153.