# semileptonic decays in madspin

Dear all,

I am trying to generate semileptonic decays from ttbar.

So I want that if t > b(W+ > qq~) then t~ > b~ (W- > ell- vl~) and if t > b(W+ > ell+ vl) then t~ > b~ (W- > q q~)

My cards are:

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proc_cards:

import model sm-ckm_no_b_mass

generate p p > t t~ @0

add process p p > t t~ j @1

add process p p > t t~ j j @2

add process p p > t t~ j j j @3

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madspin_card:

set ms_dir ./madspingrid

set Nevents_

set max_weight_ps_point 400 # number of PS to estimate the maximum for each event

set max_running_process 1

define ell+ = e+ mu+ ta+

define ell- = e- mu- ta-

define q = u u~ d d~ c c~ s s~ b b~

decay t > w+ b, w+ > c b~, t~ > w- b~, w- > ell- vl~

decay t > w+ b, w+ > ell+ vl, t~ > w- b~, w- > b c~

launch

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But the final results are completely wrong (W and t~ will not decay)

Which is the correct syntax?

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