Re: Wondering about this message in the err files

Dear Mina

these messages are not all worrying. They concern low energy (few
MeV/n) alphas generated by your proton beam in Tantalum which the BME
event generator finds to be below the Coulomb barrier threshold,
preventing their nuclear reinteraction requested by FLUKA (which in
principle would allow instead for subbarrier reaction)

As you reduce the beam energy, their energy becomes patently too low
for reinteraction and the messages disappear since FLUKA itself does no
longer require the reaction

Cheers

Francesco

**************************************************
Francesco Cerutti
CERN-EN/STI
CH-1211 Geneva 23
Switzerland
tel. ++41 22 7678962
fax ++41 22 7668854

On Fri, 14 Sep 2012, Mina Nozar wrote:

> Hello everyone,
>
> I am seeing messages of this sort when running 480 MeV protons on a Tantalum target.
> I am wondering what these messages mean and whether they are serious.
>
> I do not see the same messages with lower proton beam energy (116 MeV) on an identical setup.
>
> Thanks in advance,
> Mina
>
>
> NEXT SEEDS: F4B9F17 57 0 0 0 0 18198 2030 0 0
> COUSET, TXYZ: 1.00000000001411 -0.772441061675989 0.635086455740547
> zero reaction cross section for BME!! no interaction performed
> *** EVEBME: IJ,IBAR(IJ),ICH(IJ),IBTAR,ICHTAR,PPERNU,EPERNU -6 4 2 181 73
> 0.0933740355 0.00466953533
> ECKBME,PXKBME,PYKBME,PZKBME -0.0186902992 0. 0. 1.16573418E-15
> KP,IBRSNC(KP),ICRSNC(KP),TVRSNC(KP),ANRSNC(KP),EKRSNC(KP) 1 181 73 0.
> 168.515135 0.0186902992
> zero reaction cross section for BME!! no interaction performed
> *** EVEBME: IJ,IBAR(IJ),ICH(IJ),IBTAR,ICHTAR,PPERNU,EPERNU -6 4 2 181 73
> 0.0709440486 0.00269843562
> ECKBME,PXKBME,PYKBME,PZKBME -0.0108007683 0. 0. 1.66533454E-15
> KP,IBRSNC(KP),ICRSNC(KP),TVRSNC(KP),ANRSNC(KP),EKRSNC(KP) 1 181 73 0.
> 168.515135 0.0108007683
> zero reaction cross section for BME!! no interaction performed
> *** EVEBME: IJ,IBAR(IJ),ICH(IJ),IBTAR,ICHTAR,PPERNU,EPERNU -6 4 2 181 73
> 0.0819701173 0.00360065252
> ECKBME,PXKBME,PYKBME,PZKBME -0.014411985 0. 0. -1.60982339E-15
> KP,IBRSNC(KP),ICRSNC(KP),TVRSNC(KP),ANRSNC(KP),EKRSNC(KP) 1 181 73 0.
> 168.515135 0.014411985
> zero reaction cross section for BME!! no interaction performed
> *** EVEBME: IJ,IBAR(IJ),ICH(IJ),IBTAR,ICHTAR,PPERNU,EPERNU -6 4 2 181 73
> 0.0798297887 0.00341541256
> ECKBME,PXKBME,PYKBME,PZKBME -0.0136705428 0. 0. -1.99840144E-15
> KP,IBRSNC(KP),ICRSNC(KP),TVRSNC(KP),ANRSNC(KP),EKRSNC(KP) 1 181 73 0.
> 168.515135 0.0136705428
> zero reaction cross section for BME!! no interaction performed
> *** EVEBME: IJ,IBAR(IJ),ICH(IJ),IBTAR,ICHTAR,PPERNU,EPERNU -6 4 2 181 73
> 0.0922958615 0.00456258261
> ECKBME,PXKBME,PYKBME,PZKBME -0.0182622099 0. 0. 8.8817842E-16
> KP,IBRSNC(KP),ICRSNC(KP),TVRSNC(KP),ANRSNC(KP),EKRSNC(KP) 1 181 73 0.
> 168.515135 0.0182622099
> zero reaction cross section for BME!! no interaction performed
> *** EVEBME: IJ,IBAR(IJ),ICH(IJ),IBTAR,ICHTAR,PPERNU,EPERNU -6 4 2 181 73
> 0.0895338981 0.00429421418
> ECKBME,PXKBME,PYKBME,PZKBME -0.0171880374 0. 0. -2.10942375E-15
> KP,IBRSNC(KP),ICRSNC(KP),TVRSNC(KP),ANRSNC(KP),EKRSNC(KP) 1 181 73 0.
> 168.515135 0.0171880374
> zero reaction cross section for BME!! no interaction performed
>
>
>
Received on Sun Sep 16 2012 - 08:41:57 CEST