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Large momenta from BOX genarator [message #25342] Wed, 18 November 2020 15:52 Go to next message
AndreiSemenov is currently offline  AndreiSemenov
Messages: 6
Registered: June 2019
Location: Dubna, Russia
occasional visitor
From: *bb.netbynet.ru
Hello,
I generate single muon events with 5 GeV momentum by the BOX generator. However I get events with very large momenta from detector, so for 100,000 initial muons there are 12 events with p > 100 Gev and several events with p > 1000 events. How is this possible, is something incorrect? PandaRoot Oct19 is used.
index.php?t=getfile&id=11297&private=0
Data directly from signal_pid.root file, 100,000 initial events.
index.php?t=getfile&id=11300&private=0
Data made by tut_ana.C tutorial program. 1,700,000 initial events.
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  • Attachment: mom.jpeg
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Re: Large momenta from BOX genarator [message #25346 is a reply to message #25342] Wed, 18 November 2020 17:04 Go to previous messageGo to next message
Tobias Stockmanns is currently offline  Tobias Stockmanns
Messages: 489
Registered: May 2007
first-grade participant
From: *nc.de
Could you please check how the distribution looks like for primary particles?

Cheers,

Tobias
Re: Large momenta from BOX genarator [message #25347 is a reply to message #25346] Wed, 18 November 2020 19:31 Go to previous messageGo to next message
AndreiSemenov is currently offline  AndreiSemenov
Messages: 6
Registered: June 2019
Location: Dubna, Russia
occasional visitor
From: *bb.netbynet.ru
I use BOX generator as following:
TString inputGenerator =
"box:type(13,1)Razz(5,5):phi(0,360):tht(5,175)";
(sorry some semicolon turn into smile)
so I expect monochromatic muons in initial state. I hope following plot is relevant:

index.php?t=getfile&id=11306&private=0
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Re: Large momenta from BOX genarator [message #25351 is a reply to message #25347] Thu, 19 November 2020 07:18 Go to previous messageGo to next message
Tobias Stockmanns is currently offline  Tobias Stockmanns
Messages: 489
Registered: May 2007
first-grade participant
From: *nc.de
Dear Andrei,

could you please plot the start vertex (maybe in some projections) of the particles with momentum > 5 GeV/c and what type of particles they are?

Cheers,

Tobias
Re: Large momenta from BOX genarator [message #25364 is a reply to message #25351] Mon, 23 November 2020 19:14 Go to previous message
AndreiSemenov is currently offline  AndreiSemenov
Messages: 6
Registered: June 2019
Location: Dubna, Russia
occasional visitor
From: *bb.netbynet.ru
Hello,
Positions for particles with large momenta have relatively larger coordinates. Do not know how to draw them in a representative way.
I studied P3Cov() method of RhoCandidate that gives 3x3 covariance matrix of momentum vector. Estimating the std.dev. as square root of the sum of diagonal elements, it correlates with large momenta. The plot for correlation of this std.dev. and actual error for momentum of 5 GeV muon is attached, X is actual error and Y is std.dev. Most events have std.dev. 0.2 and actual error up to 0.5 GeV, but there are several events with std.dev. 0.2 and actual error 3 - 4 GeV, near 100% of actual value. Are there some ways of rejecting events with badly measured momenta?

index.php?t=getfile&id=11332&private=0
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