Achterberg, O.
PBAR P --> 2GAMMA X
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Search for narrow diphoton resonances and for gamma gamma + w /z signatures in p anti p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Affolder, T. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.D 64 (2001) 092002, 2001.
Inspire Record 557012 DOI 10.17182/hepdata.42918

We present results of searches for diphoton resonances produced both inclusively and also in association with a vector boson (W or Z) using 100 $pb^{-1}$ of $p\bar{p}$ collisions using the CDF detector. We set upper limits on the product of cross section times branching ratio for both $p\bar{p} \to \gamma \gamma + X$ and $p \bar{p} \to \gamma \gamma + W/Z$. Comparing the inclusive production to the expectations from heavy sgoldstinos we derive limits on the supersymmetry-breaking scale $\sqrt{F}$ in the TeV range, depending on the sgoldstino mass and the choice of other parameters. Also, using a NLO prediction for the associated production of a Higgs boson with a W or Z boson, we set an upper limit on the branching ratio for $H \to \gamma \gamma$. Finally, we set a lower limit on the mass of a 'bosophilic' Higgs boson (e.g. one which couples only to $\gamma, W,$ and $Z$ bosons with standard model couplings) of 82 GeV/$c^2$ at 95% confidence level.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


A search for heavy pointlike Dirac monopoles

The D0 collaboration Abbott, B. ; Abolins, M. ; Acharya, Bannanje Sripath ; et al.
Phys.Rev.Lett. 81 (1998) 524-529, 1998.
Inspire Record 468445 DOI 10.17182/hepdata.42158

We have searched for central production of a pair of photons with high transverse energies in $p\bar p$ collisions at $\sqrt{s} = 1.8$ TeV using $70 pb^{-1}$ of data collected with the D\O detector at the Fermilab Tevatron in 1994--1996. If they exist, virtual heavy pointlike Dirac monopoles could rescatter pairs of nearly real photons into this final state via a box diagram. We observe no excess of events above background, and set lower 95% C.L. limits of $610, 870, or 1580 GeV/c^2$ on the mass of a spin 0, 1/2, or 1 Dirac monopole.

1 data table
Table 1

No description provided.


A Measurement of single and double prompt photon production at the CERN anti-p p collider

The UA2 collaboration Alitti, J. ; Ambrosini, G. ; Ansari, R. ; et al.
Phys.Lett.B 288 (1992) 386-394, 1992.
Inspire Record 336186 DOI 10.17182/hepdata.29113

A measurement of the cross-sections for single and double prompt photon production in p p interactions at s = 630 GeV is presented. The data sample corresponds to an integrated luminosity of 13.2 pb −1 . The results are in good agreement with the predictions of perturbative QCD. The signal from double prompt photon production has a statistical significance of 4.3 standard deviations.

2 data tables
Table 1

There is an overall systematic error of 9 pct not included in the table.

Table 2

Errors quoted include statistical and all PT dependent systematic uncertainties. There is in addition a 6.8 pct overall normalization uncertainty.


Direct Photon Production in $\bar{p} p$ Collisions at $\sqrt{s}=630$-{GeV}

The UA2 collaboration Ansari, R. ; Bagnaia, P. ; Banner, M. ; et al.
Z.Phys.C 41 (1988) 395, 1988.
Inspire Record 264998 DOI 10.17182/hepdata.15558

A measurement of the direct production of photons with high transverse momentum from\(\bar pp\) collisions at\(\sqrt s= 630\) GeV is presented. The structure of events containing a high transverse momentum photon is studied. The results support predictions from QCD theory.

5 data tables
Table 1

The last data point is an average over the interval 60-100 GeV in which 5 events are found.

Table 2

No description provided.

Table 3

No description provided.

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