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			| EvtGenDirec/PHOTOS [message #22633] | Tue, 22 May 2018 13:57  |  
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					|  Alaa Dbeyssi Messages: 16
 Registered: June 2012
 | occasional visitor | From: *emp.him.uni-mainz.de 
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	| Hi, 
 I am generating the process ppbar->e+e- using EvtGenDirect and switching on PHOTOS  (release Dec17p1, macros from /pandaroot/macro/run, p=1.5 GeV).
 It seems that PHOTOS is not working properly here since the invariant mass of the e+e- is alway equal to the theoretical value 2.254 GeV (no radiative tail and no photon emission). There is also warning from PHOTOS:
 
 WARNING from PHOTOS: "Momentum not conserved in the vertex".  The log file is attached. By switching on PHOTOS, means I don't write "noPhotos" in the decay file. Is this correct?
 
 thank you for your help.
 Alaa
 ///////////////////
 The decay file is:
 
 Decay pbarpSystem
 1.0  e+ e-     PHSP;
 Enddecay
 
 End
 ///////////////////
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