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Re: Trigger efficiency

Simonetta Marcello wrote:

>Dear all,
>
>     in order to study trigger performances for BHABHA selection,
>we have performed an analysis on runs with a minimum bias
>trigger ORfino*ORfone (736000 events only GTS and TOF detectors
>selected). Therefore checks have been made on TDCs hits and
>pattern units (PU) bits.
>To study HYP selection a bigger volume of data is necessary.
>
>Keep in mind that trigger works on MeanTimer (MT) signals,
>then to evaluate the efficiency of the trigger modules
>it's relevant the comparison with software selection made using
>MT signals. On the contrary to evaluate the global efficiency
>(which contains inefficiency due to other causes, for instance
>problems on MT modules) the comparison has to be made using
>TDC hits. So this is the reason because the second way to calculate
>efficiency leads to worse values.
>
>First results are the following.
>
>
>Efficiency for trigger BTB1-3 (extended BTB with only 2 hits on Tofino)
>
>BTB 1-3 eff. = 90 %    (when trig eff. is evaluated on MT hits)
>
>BTB 1-3 eff. = 70 %    (when trig eff. is evaluated on TDC hits)
>
>
>
>Efficiency for trigger MULT2-7 BHA (multiplicity between 2-7 -included-
>performed on tofone)
>
>Mult2-7 BHA  ~= 70%
>this last number is just a pessimistic evaluation since it is not yet
>implemented in our code the selection of multiplicity on tofone inside a
>gate of 20 ns. Indeed in the trigger such a selection of multiplicity
>is done on tofone MT signals which are inside a gate of 20 ns given
>by ORtofino. Next week we will give the exact number.
>I expect to found out a better value.
>
> What we can see from this values is that trigger modules are working
>with very high efficiency, certainly with better values than those
>used in rumors. The problems seem to be in something else
>before the trigger, I mean for instance on MT signals which go
>to the trigger modules.
>
>
>
>           Simonetta Marcello and Francesca De Mori
>
>
>We are glad to inform the collaboration that the problem is solved. It was after the MeanTimer of tofino and Tofone.
>
>                                                 enjoy
>  
>
                                                                        
                        Busso and collaborators

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References: