Problem 540

Summary:	G4PreCompoundModel: Excitation energy less than zero
Product:	Geant4	Reporter:	hans-herbert.fischer
Component:	processes/hadronic/models	Assignee:	Vicente.Lara
Status:	RESOLVED WORKSFORME
Severity:	normal
Priority:	P2
Version:	5.2
Hardware:	PC
OS:	Windows

Description hans-herbert.fischer 2003-10-07 06:10:33 CEST

I'm using the LHEP_PRECO 2.6 (Pack 2.2) physics list (with defaultCutValue set
to 1 Angstroem). Simulating protons with kinetic energy 10 MeV hitting a thin
"enriched" Si layer (Si-28 only), reproducible after some 1100000 primaries
(using the default random number generator) the G4Exception:
"G4PrecompoundModel::DeExcite: Excitation energy less than 0!" occurs.

Cheers
Hans-Herbert

Comment 1 hans-herbert.fischer 2003-10-08 06:55:59 CEST

Additional information

Source code modification:
// $Id: G4PreCompoundEmission.cc,v 1.17 2003/06/16 17:07:25 gunter Exp
// GEANT4 tag $Name: geant4-05-02-patch-01
(...)
// HHFB
//  if (anU < 0.0) G4Exception("G4PreCompoundModel::DeExcite: Excitation energy
less than 0!");
    if (anU < 0.0) {
       G4cout << G4endl << "G4PreCompoundModel::DeExcite: Excitation energy less
than 0!" <<G4endl;
       G4cout << "aFragment="<<aFragment<<G4endl;
       G4cout << "momentum="<<momentum<<G4endl;
       G4cout <<
"KineticEnergyOfEmittedFragment="<<KineticEnergyOfEmittedFragment<<G4endl;
       G4cout << "EmittedMass="<<EmittedMass<<G4endl;
       G4cout << "EmittedMomentum="<<EmittedMomentum<<G4endl;
       G4cout << "anU="<< anU<<G4endl;
       G4cout << "RestMomentum.m()="<< RestMomentum.m()<<G4endl;
       G4cout << "theFragment->GetRestNuclearMass()="<<
theFragment->GetRestNuclearMass()<<G4endl;
       G4cout << "EmittedMomentum="<<EmittedMomentum<<G4endl;
       G4cout << "ResidualEcm="<<ResidualEcm<<G4endl;
       G4cout << theFragment <<G4endl;
       G4Exception("G4PreCompoundModel::DeExcite: Excitation energy less than 0!");
       }
// HHFE
(...)

Output:
G4PreCompoundModel::DeExcite: Excitation energy less than 0!
aFragment=Fragment: A = 29, Z = 15, U = 1.232e+001 MeV
          P = (-1.368e+002,-2.962e-002,-1.407e-003) MeV   E = 2.700e+004 MeV
          #Particles = 2, #Holes = 1, #Charged = 1
momentum=(-1.#IO,-1.#IO,-1.#IO)
KineticEnergyOfEmittedFragment=9.232
EmittedMass=938.272
EmittedMomentum=(-1.#IO,-1.#IO,-1.#IO;-1.#IO)
anU=1.#QO
RestMomentum.m()=1.#QO
theFragment->GetRestNuclearMass()=26053.202
EmittedMomentum=(-1.#IO,-1.#IO,-1.#IO;-1.#IO)
ResidualEcm=26053.548
PreCompound Model Emitted Fragment: A = 1, Z = 1

Comment 2 Vicente.Lara 2003-11-22 10:30:59 CET

I've not been able to reproduce the problem and I don't know what does it means
1.#QO or 1.#IO. As there are some changes in pre_equilibrium, plase, wait untill
the new release (mid/end december) and if the problem is still there submit the
bug report again.