The fermilab stdhep implementation uses a common block to read events into.
This common block is by default set to contain a maximum of 4000 particles.
The standard StdHEP DIM used by JAS uses this implementation and is thus
limited to reading events with 4000 particles.
Is it possible that the implementation you are using has been changed to
generate more than 4000 particles per event? It sounds strange since I dont
think we normally get anywhere close to 4000 particles in any of the event
samples we have generated so far.
If this is really correct we have a second experimental Stdhep DIM, which
does not use the Fermilab code and is thus not restriced to 4000 particles.
I have attached the jar file to this message. Just drop this jar file into
your extensions directory (and possibly delete HepEvt.jar which is the old
DIM).
Tony
-----Original Message-----
From: Mike Ronan [mailto:[log in to unmask]]
Sent: Friday, November 10, 2000 3:12 PM
To: tonyj
Cc: lcd-l
Subject: Error in reading Pandora_PythiaV2.1 STDHEP files directly into
JAS
Tony,
I've managed to build and Pandora_Pythia on a Solaris box at SLAC w/
very minor modifications to Masako's instructions. I'm now trying to
read in and analyze the generated events in JAS through the output
STDHEP file, but I get the following exception
java.lang.ArrayIndexOutOfBoundsException: 4000
at jasext.hepevt.HepEvent$HepEnumeration.nextParticle
at hep.lcd.util.driver.LCDHepEvent$MCHepParticle.getDaughters
...
It happens on 97/100 events that I generated w/ the following
gen_eetottbar output.dat 100 > output.list
from the examples. The Pandora_Pythia output summary looks fine (see
below), and STDHEP doesn't complain, i.e.
********************************************************
* STDHEP version 4.07 - July 14, 1999 *
********************************************************
STDXWOPEN WARNING: I/O is initialized for stdhep only
STDXEND: 513431 words i/o with 10012 efficiency
Mike
The value of the integral is 739.999 pm 11.8396
and the maximum weight found is 21772.2
...
======================================
Welcome to pandora_pythia.
======================================
--------------------------------------
Cross section = 738.543190
...
Event listing (summary)
I particle/jet KS KF orig p_x p_y p_z
E m
1 !e-! 21 11 0 0.000 0.000 250.000
250.000 0.001
2 !e+! 21 -11 0 0.000 0.000 -250.000
250.000 0.001
3 !gamma! 21 22 0 0.000 0.000 0.252
0.252 0.000
4 !gamma! 21 22 0 0.000 0.000 -0.525
0.525 0.000
5 !phasespa! 21 83 0 0.021 -0.040 0.240 499.223
499.223
6 !t! 21 6 5 101.195 130.398 -21.348 242.648
176.574
7 !tbar! 21 -6 5 -101.195 -130.398 21.621 256.575
195.241
