<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"></head><body ><div>Great points!</div><div><br></div><div>Jin</div><div><div><span class="Apple-style-span" style="font-size: 9px;"><br></span></div><span class="Apple-style-span" style="font-size: 9px;">______________________________<br><br>Jin HUANG<br><br>Brookhaven National Laboratory<br>Physics Department, Bldg 510 C<br>Upton, NY <a href="tel:11973-5000">11973-5000</a><br><br>Phone: <a href="tel:631-344-5898">631-344-5898</a><br>______________________________</span><div></div></div><div><span class="Apple-style-span" style="font-size: 9px;"><br></span></div><div></div><div></div><br><br>-------- Original message --------<br>From: Zhiwen Zhao <zwzhao@jlab.org> <br>Date:12/15/2014 12:07 PM (GMT-05:00) <br>To: Jin Huang <jinhuang@jlab.org>, 'solid ec' <solid_ec@jlab.org> <br>Cc: <br>Subject: Re: [Solid_ec] WSL -> clear fiber bundle -> PMT in STAR BEMCal <br><br>Hi, All<br><br>Other interesting things I noticed for STAR Barrel EMcal<br><br>1. fiber loops are embedded in each scintillator layer and preshower and shower are separated simply <br>by grouping readouts.<br>2. each scintillator layer has slightly different size and it was done by machining, not molding. I <br>wonder how that contributed to the total cost?<br>3. They "designed and built an intelligent Cockroft Walton PMT bases"<br>4. They used a shower-maximum-detector to get better position resolution.<br><br><br>Zhiwen<br><br>On 12/15/2014 10:49 AM, Jin Huang wrote:<br>> Dear All,<br>><br>> I recently realized there is another WSL -> clear fiber bundle -> PMT implementation for EMCal<br>> readout, similar to our proposed plan. It is built for the STAR barrel EMCal<br>> (doi:10.1016/S0168-9002(02)01970-8 <http://dx.doi.org/10.1016/S0168-9002(02)01970-8>, Fig 5). I do<br>> not recall that we discussed this particular example though. Maybe there is some technique that we<br>> can learn.<br>><br>> Like our design, it used scintillating tile -> WLS fiber for sampling and light readout. Then the<br>> WLS bundle is connected to 2.1 m long clear fiber bundle to transport the light to outside the STAR<br>> solenoidal field for a PMT readout. At the other end of the fiber bundle, another connector couple<br>> it to the PMT box. In each of the two connectors, the diameter for the fibers is increased to<br>> optimize for transmission efficiency. I was told that the connector is manufactured in Michigan.<br>><br>> However, comparing to STAR, we would require much higher energy resolution (14%/sqrt(E) + 1.5% for<br>> STAR). Therefore, the SoLID EC could be more demanding on the uniformity for the light<br>> transportation efficiency from fiber to fiber.<br>><br>> Hope this information would be useful. Expert on the STAR calorimeter includes T.M. Cormier (ORLN)<br>> and O. Tsar (UCLA).<br>><br>> Cheers<br>><br>> Jin<br>><br>> ______________________________<br>><br>> Jin HUANG<br>><br>> Brookhaven National Laboratory<br>><br>> Physics Department, Bldg 510 C<br>><br>> Upton, NY 11973-5000<br>><br>> Phone: 631-344-5898<br>><br>> ______________________________<br>><br>><br>><br>> _______________________________________________<br>> Solid_ec mailing list<br>> Solid_ec@jlab.org<br>> https://mailman.jlab.org/mailman/listinfo/solid_ec<br>><br></body></html>