Log entry time 06:34:16 on June22,2004

Entry number 126627

 After a 20 minute long beam trip, the starting septa temps
are
   Left  upper coil:  6.10 K
         lower coil:  6.25 K
   Right upper coil:  6.60 K
         lower coil:  6.35 K

With the present situation, we have roughly the same radiation
length from the remaining 4He gas as from the
target windows (0.57% each), for a total of 1.15%. 
   (compared to 3.34% for the full He cell, and 2.25% for
the dummy target).

  after 25 minutes of fairly steady beam we have 

   Left  upper coil: 6.25 K
         lower coil: 6.35 K
   Right upper coil: 6.80 K
         lower     : 6.50 K

  So, net heating at 28 µA is .15 K (right arm) and 
    0.10 K (left arm). Compare to full cell, where heating
    at this current was  (last night) 1.0 K (right arm) and
    0.70 K (left arm);  ratios of heating is a factor of 7.
    This is roughly the ratio of the He densities between 
    the full and empty cell (factor is more like 5), while
    the radiation lengths including the walls is only a factor
    of 3.

  Conclusion: The He causes most of the septum heating, there 
    is no evidence for "extra heating" from the cell materials.