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<font size="+1"><font face="monospace">Hi All,<br>
attached you find a long write up of what I tried to find out
about the information available<br>
in the root tress for the DSelector with regards to beam
photons.<br>
This will explain why the IsGenerated flag for a beam photon
sometimes will give the wrong <br>
answer. And indeed the IsGenerated flag will not always mark the
generated beam photon because<br>
it can happen that there is no beam photon available that
relates to the beam photon that generated<br>
the event.<br>
<br>
<br>
cheers,<br>
Beni<br>
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