|Message: light nucleus propagation||Not Logged In (login)|
Click on the Forum title, e.g. on the "Forums by Category" page, to read a sequence of postings to the Forum and its threads all in one page. If you are only interested in one thread or the thread following a specific posting, click the thread or the posting, which takes you to a smaller page, which contains only the part you are interested in and may be easier to navigate.
Messages are "chained" if there are only replies at the first level, i.e. 1/1.html, 1/1/1.html etc. In case of "chained" messages the message number is replaced by the icon and there is no indentation.
Inline: Display the subject line only or also the text of the posting(s); for the choice "All" the "Outline" choices are switched off.
|1||0||1||no text / full text of posting|
|2||1||All||text for level 1 only / text for All postings|
Outline: Choose the depth of the posting thread, successive toggle controls provide increasing detail.
|1||2||1||2 levels / 1 level (original posting)|
|2||3||2||3 levels / 2 levels|
|3||3||All||3 levels / all levels (all postings)|
I started with exampleN04, and made some simple changes to make it look more like STAR at RHIC.
Beam-pipe, TPC, and TOF. These are all hollow cylinders, TOF just outside the TPC.
Then using the gun, i throw 8 particles per event: pbar,p,dbar,d,tbar,t,antiHe3,He3 with kinematics
sampled from flat distributions in pt and pseudorapidity with limits. I draw the geometry and tracks
and all looks good. I see reasonable hits in the TPC and TOF.
I call "survival" occurrences of a hit in TOF from a primary (gun-generated) track. Fewer antiprotons survive than do protons, as expected. However, antinuclei have a *higher* survival probability than do the corresponding nuclei, which cannot be. This is true for any of several physics lists that i've tried: QGSP, QGSP_BIC, QGSP_BERT, QGSP_BERT_HP...
I ran Hadr00 for these same particles and several different "targets", and drew the cross-sections. Indeed, the inelastic cross-sections for antinuclei are always larger than those for the same nuclei at the same particle energy, as expected.
I've stared at verbose stepping statements, put counters and various couts in the generation, stepping and event actions, etc, but I just cannot find anything wrong.
I know it'll be difficult, but if you have any suggestions of something I could check, it'd be much appreciated... best, bill
|Inline Depth:||Outline Depth:||Add message:|