[Lowq] delayed helicity reporting correction

[Raffaella De Vita]

Hi Hovanes,
yes, the quartet signal identify the beginning of a quartet: is set to 0 
for the first state in the quartet and to 1 for the other three. This 
signal was added for eg4 and since then, as far as I know, has been 
available.
Regards
    Raffaella

Hovanes Egiyan wrote:
> Hi Raffaella,
>
> Thanks for the helicity correction code.
> What is the "Quartet signal" ? Is this the signal indicating the
> beginning of a quartet? I did not know it was in the data stream
> or even available in our electronics.
>
> Hovanes.
>
>
> Raffaella De Vita wrote:
>> Dear All,
>> you can find the code to correct for the delayed helicity reporting 
>> in my home directory under helcor_eg6 .
>> It can be compiled using the Makefile in the directory: the 
>> executable is created locally and named helcor_Linux .
>> As I mentioned the code was intended to read both bosfiles and 
>> ntuples (nt10) but I checked and it would not work on ntuple because 
>> some of the helicity related variables the code is using are not 
>> presently saved in the eg6 nt10. I tried it on bosfiles and it works. 
>> I'm presently correcting for a delayed reporting of 8 cycles: can 
>> someone confirm that this is correct?
>>
>> When launched, the code asks for the bosfile names and as outputs it 
>> creates a text file named hel_table.txt where the first 10 columns 
>> have the relevant information. The meaning of these columns is the 
>> following:
>>
>> 1)       Correction Flag: A.B
>>          A= quartet number
>>          B= state in the quartet (1,2,3,4)
>>                         > 0 if good quartet
>>                         < 0 if good quartet but missing scaler 
>> information
>>                         = 0 if bad quartet
>> 2)      First Event of Helicity state
>> 3)      Last Event of Helicity state
>> 4)      True Helicity as determined by this code
>> 5)      True Helicity as determined by Sergey code (now set to 2 
>> because the online code is not running)
>> 6)      Reported Helicity
>> 7)      Sync signal
>> 8)      Quartet signal
>> 9)      TGBI helicity Counter
>> 10)     Interrupt Time from microsec clock
>>
>> The other columns are all set to 0 because apparently there are no 
>> helicity scaler banks (HLS and HLB) in the bosfiles. I don't know if 
>> this was meant to be.
>> Because the helicity scaler information are missing, the correction 
>> flag is set to negative values (see above).
>>
>> To apply the correction is sufficient to read the table and assign 
>> the helicity written in column #4 to all the events with numbers 
>> between the ones in column 2 and 3.
>> Helicity states for which the correction flag (column 1) is set to 0 
>> should be disregard because either the information to get the correct 
>> helicity was missing (last states of each file) or the quartet the 
>> state belongs to is incomplete (first state of each file or before 
>> and after a beam trip).
>>
>> Best regards
>>     Raffaella
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>