GSI Forum: Event Generators » DPM weird t spectrum (random problem)

Home » PANDA » PandaRoot » Event Generators » DPM weird t spectrum (random problem)

Show: Today's Messages :: Polls :: Message Navigator

DPM weird t spectrum (random problem) [message #13961]

Mon, 17 September 2012 17:30

Stefan Pflueger
Messages: 99
Registered: February 2012

continuous participant

From: *kph.uni-mainz.de

Hi,

I'm obtaining very strange data, when using the standalone version of DPM (settings: tmin 0.025 degrees, only the elastic part).
I attached two plots showing this. Both show the -t distribution. dpmprob-125binning shows the distribution with a binning of 125, because the effect is the most dramatic in this case. For dpmprob-400binning a few single outliers are present...

Am I missing something?

Best regards,

Stefan

Attachment: dpmprob-125binning.pdf
(Size: 18.28KB, Downloaded 438 times)
Attachment: dpmprob-400binning.pdf
(Size: 21.51KB, Downloaded 445 times)

Report message to a moderator

Re: DPM weird t spectrum (random problem) [message #13962 is a reply to message #13961]

Mon, 17 September 2012 18:13

StefanoSpataro
Messages: 2736
Registered: June 2005
Location: Torino

first-grade participant

From: 134.158.79*

I found strange that with a higher binning the effect disappears, while with a worse binning you can see such obscillations, are you sure you don't have some bug in the macro? Maybe something connected with rounding?

However, Aida Galoyan is doing the DPM manteinance, so maybe you can contact her, I am not sure of she reads the forum.

Report message to a moderator

Re: DPM weird t spectrum (random problem) [message #13969 is a reply to message #13962]

Tue, 18 September 2012 17:30

Stefan Pflueger
Messages: 99
Registered: February 2012

continuous participant

From: *kph.uni-mainz.de

Hi,

yeah this made me wonder as well. I think my program/macro should be bug free. Anyways, I changed the DPM code to use 8 byte reals instead of 4 to gain some precision and that seems to cure the outlier problem. I guess that that my tiny t range compared to the full dpm generated t range scratched the resolution. I'll pass that information to Aida.

Stefan

Report message to a moderator

Previous Topic:	EvtGen update?
Next Topic:	DPM wrong coulomb/hadron elastic ratio

Goto Forum:

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Sat May 09 22:09:07 CEST 2026

Total time taken to generate the page: 0.00724 seconds