[BLASTTALK] Ion Pol. results

From: Genya (evgeni@mit.edu)
Date: Sat Jun 21 2003 - 00:51:04 EDT


    We had beam from 6 to about 10pm. Then there were some transmitters
problems beam came back after midnight.
    Also, we do have some software bugs. In particular, it appears to be
some mess in the database for HV (Adam? We'll talk about it Monday, I
suppose).
   Other then that, IP worked like a charm. Unfortunately, we were able to
take data only on ABS (with discharge on and off), and on unpolarized hydrogen.
No data were taken as yet on deuterium (unpolarized, or through ABS). Hopely,
Vitalij will finish it this night shift.
   Nevertheless, it appears we have excellent separation of mass 1 and mass 2.
We do need deuterium data just to confirm our data. Conclusions:
  1. Problem with unpolarized target is gone (at least with a warm cell).
  2. Even with unpolarized target there is mass 1 signal (I suppose, it is
double ionization, or dissociation by the electron beam). The amplitude of the
signal is of the order of 10% of mass2 signal.
  3. With a warm cell, the ratio molecules/atoms is about 4. If one recalls that
there are 2 atoms in every molecule, the ratio becomes 8:1. Half of mass 1 signal
corresponds to this double-ionization, so the real ratio is probably 16:1. If we'll
get the same result with a cold cell, it will be clear that the polarization is gone
due to recombination in the cell.
   I strongly advocate that the cell to be cooled Sunday night/morning. Yuan and me
have 8-16 shift Sunday, we could measure the data with a cold cell.
       Genya
PS Please find attached measured mass spectra for hydrogen. I apologize, but it is
in Excel format...




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