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Hello, everyone.</div>
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I am planning to submit an abstract to the upcoming SESAPS meeting (in November). A draft is below -- comments are welcome. I plan to submit at the end of this week.</div>
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Simon</div>
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Status of the JLab Eta Factory (JEF) experiment</div>
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<span>The JLab Eta Factory (JEF) experiment is an approved experiment in Hall D at
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<div>Jefferson Lab that focuses on decays of $\eta$ mesons with<br>
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<div>emphasis on the rare $\eta\to\pi^0\gamma\gamma$ channel. In addition to <br>
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<div>providing a rare window into higher-order chiral perturbation theory, this <br>
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<div>channel can be used to search for evidence of dark matter. A potential <br>
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<div>extension to the Standard <br>
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<div>Model posits a dark gauge boson(``B'') that couples predominately with quarks
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<div>and can be observed in the $\eta\to\gamma B$, $B\to\pi^0\gamma$. The same set
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<div>of final state particles can also be used to look for a scalar dark matter <br>
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<div>mediator $S$ in the channel $\eta\to\pi^0S$, $S\to\gamma\gamma$.<br>
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<div>In order to achieve the requisite<br>
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<div>resolution to observe these rare channels, this experiment calls for an <br>
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<div>upgrade to the existing GlueX equipment, which is a fixed target apparatus <br>
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<div>based on a 2-Tesla solenoid magnet. Neutral particles emerging after the <br>
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<div>interaction of a photon beam with a liquid hydrogen target are detected in the
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<div>forward direction in the Forward Calorimeter (FCAL), an array of lead glass blocks.
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<div>We plan to replace the $\sim$80$\times$80 cm$^2$ region of the FCAL <br>
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<div>closest to the beam line with an array of 2$\times$2$\times$20 cm$^3$ lead <br>
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<span>tungstate crystals. The current status of the JEF project will be presented.</span><br>
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