Search for Large Extra Dimensions in Final States Containing One Photon or Jet and Large Missing Transverse Energy Produced in $p\overline{p}$ Collisions at $\sqrt{s}=1.96\mathrm{TeV}$

We present the results of searches for large extra dimensions in samples of events with large missing transverse energy ${\mathrm{E̸}}_T$ and either a photon or a jet produced in $p\overline{p}$ collisions at $\sqrt{s}=1.96\mathrm{TeV}$ collected with the Collider Detector at Fermilab II. For $\gamma +{\mathrm{E̸}}_T$ and $\mathrm{\text{jet}}+{\mathrm{E̸}}_T$ candidate samples corresponding to 2.0 and $1.1{\mathrm{fb}}^{-1}$ of integrated luminosity, respectively, we observe good agreement with standard model expectations and obtain a combined lower limit on the fundamental parameter of the large extra dimensions model $M_D$ as a function of the number of extra dimensions in the model.

Figure 1

Predicted (solid) and observed (crosses) photon $E_T$ distributions for the $\gamma +{\mathrm{E̸}}_T$ candidate sample. The last bin shows all events containing a photon with $E_T>180\mathrm{GeV}$. The expected LED signal for the case of $n=4$ and $M_D=0.8\mathrm{TeV}$ is also shown. The kinematic region above 90 GeV is used for constraining the ADD model. The hatched region indicates the total uncertainty on the combined background prediction.

Figure 2

Predicted and observed leading jet $E_T$ distributions for the $\mathrm{\text{jet}}+{\mathrm{E̸}}_T$ candidate sample. The expected LED signal contribution for the case of $n=2$ and $M_D=1.0\mathrm{TeV}$ is also shown.

Figure 3

95% C.L. lower limits on $M_D$ in the ADD model as a function of the number of extra dimensions in the model.