OVERVIEW & OPERATIONS WINDOWS:
The Endcap EMC comprises tower, shower maximum (SMD), and both Pre-Shower, and Post-Shower, detector subsystems.
Briefly:
The towers are read out by single anode PMT's housed in magnetically shielded boxes and associated Front End Electronics (FEE) crates located on the back of the STAR poletip; the SMD, Pre- and Post-Shower on the other hand, are all read out by Multi-Anode PMT's (MAPMT) and compact FEE enclosed in shielded boxes (also on the back of the poletip). The High Voltage for the (MA)PMT's, LV power for the FEE, data collectors and slow controls all reside in EEMC racks located along the Wide Angle Hall (WAH) west wall. An air blower for tower FEE crate cooling and a chiller unit giving H2O cooling of the MAPMT FEE box electronics are also located there.
The EEMC systems for shift crews/experts to control and monitor are the LV power, tower FEE, MAPMT FEE and High Voltage systems. High voltage for both PMT and MAPMT have a common controller system ("HVSys") for their Crockroft-Walton bases. Separate VME crates in the EEMC WAH racks contain the slow controls (VxWorks CPU) and data collector modules, respectively. The screens allowing control of these various systems are indicated briefly below and further discussion of startup, normal operation/monitoring, trouble shooting alarms, and etc. are given in other sections of this writeup.
In addition to operation as a stand alone STAR detector subsystem, the EEMC is an important part of STAR triggering for much of the physics program. Hence QA of its operational health, including all aspects related to trigger performance is essential. Such monitoring is done via the "Panitkin plots" (P-plots) produced during each run and whose description relevant to the EEMC is also given elsewhere in this document.