## A Study of Anomalous Production of Z-Bosons with High Transverse Momentum at the Tevatron

We present a broad search for signatures containing a high transverse  momentum Pt Z boson in 0.94 pb-1 of CDF-II data. In addition to
inclusive production of  Z's with large values of Pt, we investigate  signatures that have a  much smaller Standard Model crossection, and
hence are more sensitive to new phenomena, such as right-handed heavy quarks, technicolor particles, gauginos or squarks, or excited states resulting from  large extra dimensions. The specific channels in   which we search are of the form Z + X + anything and Z + X + Y + anything, where X and  Y can be leptons, photons, missing energy, or large total transverse energy ($H_T$). For each signature we compare the observed Pt(Z) spectra and other distributions with Standard Model expectations.  Alas, we do not see anything striking, yet.

# Inclusive part.

Invariant mass (left) and transverse momentum (right) for Z --> ee. The two lower plots show the difference between the numbers of expected and observed events divided by the number expected.
A mass cut of 66 < M(ee) < 116 GeV has been applied to the right-hand plot.

PDF or GIF.
The Bayesian limit on the differential cross section for anomalous Z --> ee production at 95% CL.

PDF or GIF

# Signature Part

## Z+X+anything

 X Observed Expected +\sigma -\sigma Lepton 3 1.6 0.3 0.3 Photon 14 12.4 1.5 1.5 Missing Energy 97 85.4 12.3 12.3 Ht 45 36 4.9 5.8

## Z+X+Y+anything

 X+Y Observed Expected +\sigma -\sigma Lepton+Photon 0 0.001 0.001 0.001 Lepton+Missing Energy 1 0.72 0.11 0.11 Lepton+Ht 0 0.16 0.04 0.04 Photon+Missing Energy 1 0.24 0.20 0.20 Photon+Ht 1 0.80 0.34 0.23 Missing Energy+Ht 6 6.6 1.0 1.0

# Inclusive part.

Invariant mass (left) and transverse momentum (right) for Z --> µ+µ-. The two lower plots show the difference between the numbers of expected and observed events divided by the number expected.
A mass cut of 66 < M(µµ) < 116 GeV has been applied to the right-hand plot.

PDF or GIF.
The Bayesian limit on the differential cross section for anomalous Z --> µµ production at 95% CL.

PDF or GIF

# Signature Part

## Z+X+anything

 X Observed Expected +\sigma -\sigma Lepton 2 2.4 0.4 0.4 Photon 14 15.0 1.8 1.8 Missing Energy 74 55.9 9.7 5.8 Ht 53 41.3 5 5.2

## Z+X+Y+anything

 X+Y Observed Expected +\sigma -\sigma Lepton+Photon 0 0.001 0.001 0.001 Lepton+Missing Energy 0 0.8 0.1 0.1 Lepton+Ht 0 0.14 0.05 0.04 Photon+Missing Energy 0 0.19 0.21 0.10 Photon+Ht 0 0.28 0.14 0.13 Missing Energy+Ht 6 3.5 0.5 0.5

# Event Displays

## 2. Z->ee + Lepton + Missing energy

Page was last updated August 22, 2006 by Alexander Paramonov.
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