Search for Long-Lived Parents of the Z Boson

Search for Long-Lived Parents of the Z⁰ Boson

We present the results of our search for particles with long lifetime that decay to a Z⁰ boson. The possibility of a long-lived parent of the Z⁰ is predicted by several models, such as a fourth generation quark and supersymmetry and with a gravitino LSP. We vertex dimuons with invariant mass within the Z⁰ mass window. We find no evidence of signal, and so set cross section limits using the fourth generation quark model.

Contacts: Adam L. Scott and David Stuart
Data: Run II, 163 pb^-1
Documentation: PS, PDF

Plots and Tables:

Acceptance * Efficiency:
	Acceptance * efficiency as a function of lifetime, for a b' mass of 150 GeV. Available formats: GIF, EPS
	Acceptance * efficiency as a function of mass, for a b' lifetime of 10 mm. Available formats: GIF, EPS
Data:
	Unblinded L_xy distribution, with the Z⁰ boson p_T cut. Available formats: GIF, EPS
	Unblinded L_xy distribution, without the Z⁰ boson p_T cut. Available formats: GIF, EPS
Cross Section Limits:
	Cross section limit as a function of lifetime, for a b' mass of 150 GeV, compared to the theoretical cross section. Available formats: GIF, EPS
	Cross section limit as a function of mass, for a b' lifetime of 10 mm, compared to the theoretical cross section. Available formats: GIF, EPS
Lifetime vs. mass exclusion region:
	Using the theoretical prediction displayed in the cross section limit plots, we set a 95% confidence exclusion region in mass and lifetime parameter space. Available formats: GIF, EPS
	Same plot as above, with the Run I result overlaid. Available formats: GIF, EPS

Page page: http://www-cdf.fnal.gov/physics/exotic/r2a/20040826.mumulxy_longlifez/index.html was last updated October 21st, 2004 by Stephan Lammel.
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