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Under some circumstances, new massive particles arising from physics beyond the Standard Model will have lifetimes that are long compared to the transit time through the detector. In these cases, direct searches for decay products will fail, and the limits obtained will not hold. If such a particle is charged, it will appear in the detector as a slowly moving, highly ionizing and highly penentrating particle with large transverse momentum that will typically be reconstructed as a muon. We present the results of a model-independent search for charged massive stable particles by measuring the time-of-flight of high transverse momentum tracks in events collected using a high transverse momentum muon trigger. Our results, based upon 1.03 fb-1 of pbar-p collisions at sqrt{s} = 1.9 TeV, are consistent with background. We set a model independent limit on the production cross section of a single fiducial strongly interacting CHAMP of 48 fb at 95% C.L., and 10 fb for a single fiducial weakly interacting CHAMP. Within the context of a general model of stable stop pair production, we set a lower stop mass limit of 250 GeV/c2 at 95% C.L.


Plots and Tables:

Momentum_Sig_Ctl_Lin Momentum_Sig_Ctl_Lin

Momentum for the control region and signal region in the $W\to e\nu$ dataset.

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TOF_beta_Sig_Ctl_Lin TOF_beta_Sig_Ctl_Lin

TOF beta for the control region and signal region in the $W\to e\nu$ dataset.

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TOFmass_Sig_Ctl_Linear TOFmass_Sig_Ctl_Linear

TOF mass for the control region and signal region in the $W\to e\nu$ dataset.

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t0DiffCut t0DiffCut

TOF $t_0$ $-$ COT $t_0$ in the $W\to e\nu$ dataset.

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TOFmass_Ctl_pred_cut_Wenu TOFmass_Ctl_pred_cut_Wenu

Control-region mass (after cleanup cuts) calculated from $\beta_{\rm TOF}$ and the track momentum for the $W\to e\nu$ dataset. The histogram is for all control-region events, while the red line is the prediction.

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TOFmass_Signal_pred_cut_Wenu0 TOFmass_Signal_pred_cut_Wenu0

Signal-region mass calculated from $\beta_{\rm TOF}$ and the track momentum for the $W\to e\nu$ dataset. The histogram is for events after cleanup cuts, while the red line is the prediction using the control-region $\beta$.

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TOFmass_Signal_pred_Int_cut_Wenu TOFmass_Signal_pred_Int_cut_Wenu

Signal-region mass calculated from $\beta_{\rm TOF}$ and the track momentum for the $W\to e\nu$ dataset. The histogram is for events after cleanup cuts, while the red line is the prediction using the control-region $\beta$.

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Momentum_Sig_Ctl_Lin_CMUP Momentum_Sig_Ctl_Lin_CMUP

Momentum for the control region and signal region in the central muon dataset.

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TOF_beta_Sig_Ctl_cut_Lin_CMUP TOF_beta_Sig_Ctl_cut_Lin_CMUP

TOF beta for the control region and signal region in the central muon dataset.

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TOFmass_pred_cut_CMUP TOFmass_pred_cut_CMUP

Mass calculated from $\beta_{\rm TOF}$ and the track momentum for the central muon dataset. The histogram is for events after cleanup cuts, while the red line is the prediction using the $20 < p_T < 40$ GeV control-region $\beta$.

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TOFmass_pred_cut_CMUP_Stop TOFmass_pred_cut_CMUP_Stop

Mass calculated from $\beta_{\rm TOF}$ and the track momentum for the central muon dataset. The histogram is for events after cleanup cuts, while the red line is the prediction using the $20 < p_T < 40$ GeV control-region $\beta$. The blue line shows the additional events expected for a 220 GeV/$/c^{2}$, and the magenta line shows the addtional events expected for a 220 GeV/$/c^{2}$ stop.}

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TOFmass_pred_Int_cut_CMUP TOFmass_pred_Int_cut_CMUP

Mass calculated from $\beta_{\rm TOF}$ and the track momentum for the central muon dataset. The histogram is for events after cleanup cuts, while the red line is the prediction using the $20 < p_T < 40$ GeV control-region $\beta$.

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ExpectedStop ExpectedStop

Stop expected signal as a function of stop mass.

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expectedLimit expectedLimit

The theoretical NLO cross section for stop production, calculated using the Prospino program, is plotted as a function of stop mass (red), along with the limits expected for this analysis.

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StopXSecLimitCMUP StopXSecLimitCMUP

The theoretical NLO cross section for stop production, calculated using the Prospino program~\cite{prospino}, is plotted as a function of stop mass (red), along with the cross section limit for the observed CMUP result.

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