I doubt that there was a problem with the database ( which is currently just a file).
Either you have the right voltages on the channels and it worked, or you don't and it
didn't. As a note, as per Yuan's instructions the voltages are different if the crate
is in standby or operation, basically -500 V for those voltages whose value is more
negative than -1000 for operation. Any switching between standby and operation will
overwrite any changes that you have made to those channels. To make the changes part
of the save sets, you have to hit the set button on the main hv control window next to
the ion polarimeter related display. Also if you reboot you will lose those settings
too. To make them even more permanent, Yuan knows where the simple text file that
records them is. The file was just a quick and dirty way to enter the ion polarimeter
into the hv control. Also if you do not like the trip currents that I set for them,
Yuan can change them there too. At some point soon I will switch to the mysql database,
but for now the easiest thing is to access the file.
I will not be there Monday, so if you could be more specific now, I can see what
problems you are having and try to correct them as needed this weekend.
Adam
Genya wrote:
> 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...
>
> ------------------------------------------------------------------------
> Name: Masses06-20-03.xls
> Masses06-20-03.xls Type: Microsoft Excel Worksheet (application/vnd.ms-excel)
> Encoding: base64
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