| | 2 | |
| | 3 | An effort should now be done to bring v5 towards handling multiparton processes. |
| | 4 | We are not aiming to a full MadEvent independent solution and we would be already happy |
| | 5 | if we could build a code that could run in a reasonable time for pp>V+5partons (so to do V+4 jets at NLO), |
| | 6 | pp>5 partons (so to do 4 jets at NLO). In fact, we are trying to get something working |
| | 7 | up to 1/Nc^2 corrections (included). In this case we could go higher in multiplicity |
| | 8 | (up to pp> 7 partons so to do pp>6 jets at NLO). |
| | 9 | |
| | 10 | The main line of optimization concerns multi-gluon amplitudes. At this stage we focus only |
| | 11 | on these. The reason is simple: once two quark lines are included then any other multi-quark |
| | 12 | subproc is suppressed in the number of colors and also kinematically (the latter is not a theorem |
| | 13 | but by experience it is true). |
| | 14 | |
| | 15 | We suggest to proceeed in steps. |
| | 16 | |
| | 17 | === First Step : getting a code for pp>X + n gluons exact at all 1/Nc^n and compiling. === |
| | 18 | |
| | 19 | This should be achieved rather easily, if we don't worry about SPEED (which we will in the next step, of course). |
| | 20 | Anyway is mandatory to have a code that can do |M|^2 EXACTLY (at all orders in 1/Nc^n). Note that the current |
| | 21 | algorithm that gets the color matrix is already able to select powers in 1/Nc so this is not an issue. |
| | 22 | |
| | 23 | |
| | 24 | |
