CSV Fall 2018 Run Plan

Fall 2018 run plan

Goal

The goal of the E12-09-002 experiment is to measure the ratio of semi-inclusive pi+ and pi- production from LD2 for the purpose of looking for Charge Symmetry Violation (CSV) in quark distributions.

Experimental setup

• Main trigger is ELREAL (electron PID trigger) in the HMS in coincidence with 3/4 in the SHMS.
• HMS is setup for detecting electrons (inclusive DIS measurement).
• SHMS is setup for detecting charged pions and kaons (semi-inclusive DIS measurement).

Settings to monitor during shift

• Beam energy: 10.6 GeV. Raster 2x2
• Beam current:
  • The nominal beam current is 50 muA for pi- and 25 muA for pi+. The main goal is to keep the total rate in the pion arm the same at both polarities (500 kHz or less). If the rate exceeds 500 kHz, please adjust the beam current accordingly.
• Trigger:
  • Main trigger is ELREAL (TRIG3) in HMS in coincidence with 3/4 (TRIG1) in SHMS.
• Prescale: PS5=0 all the time. Adjust PS3 and PS1 to get about 100 Hz of singles in each arm.