347 f(-p1) + b(-p2) Z(e-(p3) + e+(p4)) + b(p5) + f(p6) + b(p7)

347.1 Z + Q+jet production, processes 341–357

These processes represent the production of a Z boson that decays into a pair of electrons, in association with a heavy quark, Q and an untagged jet. For more details on this calculation, please see Ref. [1].

For processes 341 and 351 the initial state at lowest order is the heavy quark and a gluon and the calculation may be performed at NLO. Thus in these processes the quark Q occurs as parton PDF in the initial state. As for H + b and Z + Q production, the matrix elements are divided into two sub-processes at NLO. Thus the user must sum over these after performing more runs than usual. At lowest order one can proceed as normal, using nproc=341 (for Zbj) or nproc=351 (for Zcj). For a NLO calculation, the sequence of runs is as follows:

The sum of these yields the cross-section with one identified heavy quark and one untagged jet in the final state when inclusive is set to .false. . To calculate the rate for at least one heavy quark and one jet (the remaining jet may be a heavy quark, or untagged), inclusive should be .true..

Processes 346,347 and 356,357 are the lowest order processes that enter the above calculation in the real contribution. They can be computed only at LO.

When removebr is true, the Z boson does not decay.

347.2 Plotter

nplotter_auto.f is the default plotting routine.

347.3 Example input and output file(s)

input347.ini process347.out

References

[1]    J.M. Campbell, R.K. Ellis, F. Maltoni and S. Willenbrock, Production of a Z boson and two jets with one heavy-quark tag, Phys. Rev. D 73 (2006) 054007 [hep-ph/0510362].