On Shift: Bettoni, Pastrone

The beam instability problem was not solved until 19:30, when MCR called
to say that the beam energy was stable at Ecm = 3685.55. At that point,
since we were 450 keV below the psi prime peak, we decided to go down to
Ecm = 3635 MeV (etac prime search).

We started data taking at 20:40 with run 846, which stopped after 35
minutes due to an I/O error on tape drive drv11. 

We then started run 847, which finished just before the end of the shift.
We have run in constant luminosity mode (2.4 * 10**31 cm-2 sec-1). 

Summary of data taken:

run 846  39 nb-1
run 847 201 nb-1

Diego and Nadia