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I didn’t set anything…I took it from the previous (2014) settings since nobody told me any different (I had asked the ECAL folks if the settings were were ok but understandably didn’t get a thumbs up/down). I said 32ns since I thought deadTIme=32 means the deadtime is 32ns…why would I think that? I don’t know... > On May 8, 2015, at 6:45 PM, Sho Uemura <[log in to unmask]> wrote: > > Matt, where did you set this 32 us dead time? I don't see this in the steering file; all I see is TriggerDriver.deadTime = 32, which is in units of 2 ns clocks - so it's 64 ns. > > On Thu, 7 May 2015, Valery Kubarovsky wrote: > >> Hi Matt, >> >> I suggest to take out dead time at all. DAQ changes configuration every other day. We have ungated rate in epics to compare with. 12 kHz is ungated rate. >> So we don't have 2.5% coincidence any more. 32 us dead time per event with 12kHz rate corresponds 62% live time. So your ungated rate is 19 kHz ( compare with 12 kHz). And you have to scale trigger cuts in accordance with correction factor. >> >> Any way the coincidence is very well in my view! >> >> It will be extremely interesting to take a look to your histograms. >> >> Regards, >> Valery >> >> >> >> >>> On May 7, 2015, at 18:26, Graham, Mathew Thomas <[log in to unmask]> wrote: >>> >>> CCing the list as this is coming up a lot. >>> >>>> On May 7, 2015, at 3:04 PM, Valery Kubarovsky <[log in to unmask]> wrote: >>>> >>>> Hi Matt, >>>> Can you write in more details what is actually included in your MC simulation? >>> >>>> I just don't understand what is beam and enhanced tridents. >>> >>> At the generator level: >>> >>> the beam is simulated using EGS5 which includes multiple and single scattering,small-angle brems, and mollers. It does not include wide-angle bremstralung though. We insert trident events (generated by MADGRAPH) at the rate given by the calculated cross-section. The tridents generated for this have essentially no generator level cuts. >>> >>> The enhanced tridents have generator-level cuts so that they are more likely to be in our acceptance and pass the trigger. There are cuts on minimum angle (>10mrad for the positron and at least one of the electrons), minimum lepton energy etc. I see as I look at the generator file that, for this sample, there was an e+e- energy sum cut at >0.88 GeV. This is good for studying more radiative-like events, but we should probably generate events with this loosened as well as that?s not in the trigger. >>> >>>> Can I compare your eats with measured by HPS, that is exactly 12 kHz. I don't think that you simulate DAQ operation. So you don't have dead time in your estimation of the trigger rate. >>> >>> I would definitely take the rate from the MC with a grain of salt?the 2.5% agreement right now is no doubt a coincidence. >>> >>> There is deadtime in the simulation, but I have it set a bit high (32us) and I think we had the hold-off as 25 or 21.5. Sho can comment more as he wrote the readout simulation. >>> >>>> What kind of cuts do you apply? >>>> You know that MC and data have des relaunch in the energy deposition to the EC calorimeter. So you have to have different cuts then we are using in the trigger setup. >>> >>> I didn?t scale the cuts at this point?just used them straight from what Kyle sent. >> >> ######################################################################## >> Use REPLY-ALL to reply to list >> >> To unsubscribe from the HPS-SOFTWARE list, click the following link: >> https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=HPS-SOFTWARE&A=1 >> ######################################################################## Use REPLY-ALL to reply to list To unsubscribe from the HPS-SOFTWARE list, click the following link: https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=HPS-SOFTWARE&A=1