Guidelines for Dumping both Beams
- Always measure proton beam emittance with wire scanner after beams are brought
to collisions, before lumi run is declared.
If proton beam emittance > 30 pi mm mrad, dump both beams.
- If proton background too high for all three experiments, measure proton
beam emittance (requires turning off HV).
- If proton beam emittance > 30 pi mm mrad, dump both beams.
- If proton background too high for one experiment, background acceptable
for other experiments, try to tune background conditions for about 1 hour, including measures which may require turning off HV (e.g. moving proton
collimators).
If not successful, measure proton beam emittance (requires turning off HV).
- If proton beam emittance > 30 pi mm mrad and Ie < 20mA,
HERMES high density run for 1 hour.
Dump both beams after HERMES high density run.
- If proton beam emittance > 30 pi mm mrad and Ie > 20mA,
dump both beams.
These guidelines should be not used as strict rules. They should help the
experiments to come to an agreement when the beams are dumped.
The final decision whether the beams are dumped will be taken by HERA.