238 f(-p₁) + f(-p₂) →t(→ e^-(p₃) + ν(p₄) + b(p₅)) + b(p₆) + q(p₇), (t-channel)

238.1 t-channel single top with an explicit b-quark, processes 231–240

These represent calculations of the t-channel single top (231) and anti-top (231) processes in a scheme with four flavours of quark in the proton, so that b-quarks are not present in the proton. The b-quark is instead explicitly included in the final state. For more details on this calculation, please see Ref. [1].

Processes 232 and 236 represent t-channel single top production in association with a further jet and may be calculated at LO only.

Processes 233 and 238 are the complete four-flavour scheme t-channel single top production processes. These are therefore the processes that should be used for most physics applications. When one wishes to calculate observables related to the decay of the top quark, removebr should be false in processes 233 and 236. The LO calculation proceeds as normal. At NLO, there are two options:

• part=virt, real or tota : final state radiation is included in the production stage only

• part = todk : radiation is included in the decay of the top quark also and the final result corresponds to the sum of real and virtual diagrams. Note that these runs automatically perform an extra integration, so will take a little longer.

Processes 234 and 239 give the extra contribution due to radiation in top decay. These processes are mainly of theoretical interest.

Processes 235 and 240 are the leading order single top processes with an extra radiated parton. These processes do not includes jets produced in the decay process.

238.2 Plotter

nplotter_4ftwdk.f is the default plotting routine.

238.3 Example input and output file(s)

input238.ini process238.out

References