Log entry time 13:18:12 on July20,2005

Entry number 148714

 
 Jian-Ping and I make an access (no beam; they are setting up
Hall C first) in order to bleed off some gas to reduce the density.
We aim for a 15% reduction, and due to JP's skill we get
exactly there!

We were at 6.4 K and 200 psi: 0.136 g/cc.

We are now at 6.4 K and 117 psi: 0.116 g/cc.

Present target conditions:

High power heater: 148 W
CHL 4K flow: 17 g/s
Htr_fore:  6.48 K
Htr_after : 6.39 K  (we regulate on this one)  
Cell_after: 6.50 K
Pressure: 117 psi
fan speed: 60 Hz
Differential Pressure: 0.035 inches of H2O (in-out)

Adjust alarm limits on cell pressure.  

Goals

See how much septum heating is reduced. It
certainly better change!
See how density fluctuations are affected.
Get spectrometer DAQ data to look at deltaP
spectrum, see how elastic He radiative tail vs.
QE He vs. Al windows changed...
 

13:15 - we are out of access, and MCC is ready to
send us tune beam; they have finished setting up Hall C,