Standard Model + ATGC (Warsaw basis)

This model is a reparametrisation of the Standard Model + ATGC model file, which parametrises the anomalous triple gauge boson couplings of mass dimension six in terms of the Standard Model effective field theory in the Warsaw basis [HLP+25]:

\[\mathcal{L}^{\mathrm{eff}.} = \mathcal{L}^{\mathrm{SM}} +\sum_i \frac{c_6^i}{\Lambda^2} \mathcal{O}_{6, \, \mathrm{Warsaw}}^i +\sum_i \frac{c_8^i}{\Lambda^4} \mathcal{O}_8^i ,\]

The fields correspond to the ones in the SM.

Parameters and power-counting

Besides the usual power-counting Wilson coefficients carry the power \(\mathrm{LAM}\) (similar to \(\mathrm{QED}\), \(\mathrm{QCD}\)) corresponding to \(\Lambda^{-2}\). For the dimension 6 operators the following parameters can be set

Parameter

Recola identifier

Operator

Order

\(c_{W}/\Lambda^2\)

'CWD6'

\(\epsilon_{ijk} \hspace{0.25mm} W^{i, \nu}_{\mu} \hspace{0.25mm} W^{j, \lambda}_{\nu} \hspace{0.25mm}W^{k, \mu}_{\lambda}\)

\(\mathrm{LAM}^1\)

\(c_{HB}/\Lambda^2\)

'CHBD6'

\(H^{\dagger} H \hspace{0.25mm} B_{\mu \nu} B^{\mu \nu}\)

\(\mathrm{LAM}^1\)

\(c_{HW}/\Lambda^2\)

'CHWD6'

\(H^{\dagger} H \hspace{0.25mm} W_{\mu \nu}^i W^{i, \mu \nu}\)

\(\mathrm{LAM}^1\)

\(c_{HW\!B}/\Lambda^2\)

'CHWBD6'

\(H^{\dagger} \sigma^{i} H \hspace{0.25mm} W^{i}_{\mu\nu} B^{\mu\nu}\)

\(\mathrm{LAM}^1\)

\(c_{\tilde{W}}/\Lambda^2\)

'CWtildeD6'

\(\epsilon_{ijk} \hspace{0.25mm} W^{i, \nu}_{\mu} \hspace{0.25mm} W^{j, \lambda}_{\nu} \hspace{0.25mm} \widetilde{W}^{k, \mu}_{\lambda}\)

\(\mathrm{LAM}^1\)

\(c_{H\tilde{B}}/\Lambda^2\)

'CHBtildeD6'

\(H^{\dagger} H \hspace{0.25mm} B_{\mu \nu} \widetilde{B}^{\mu \nu}\)

\(\mathrm{LAM}^1\)

\(c_{H\tilde{W}}/\Lambda^2\)

'CHWtildeD6'

\(H^{\dagger} H \hspace{0.25mm} W_{\mu \nu}^{i} \widetilde{W}^{i, \mu \nu}\)

\(\mathrm{LAM}^1\)

\(c_{H\tilde{W}\!B}/\Lambda^2\)

'CHWtildeBD6'

\(H^{\dagger} \sigma^{i} H \hspace{0.25mm} \widetilde{W}^{i}_{\mu\nu} B^{\mu\nu}\)

\(\mathrm{LAM}^1\)

The dimension eight contributions for the neutral sector are identical to the ones in the Standard Model + ATGC model file.

Parameter

Recola identifier

Operator

Order

\(c_{BW}/\Lambda^4\)

'CBWL4'

\(-\mathrm{i} \Phi^\dagger B_{\mu\nu} \frac{\tau_i}{2} W^{\mu\rho\;i} \left\{D_\rho, D^\nu\right\}\Phi + \mathrm{h.c.}\)

\(\mathrm{LAM}^2\)

\(c_{WW}/\Lambda^4\)

'CWWL4'

\(\mathrm{i} \Phi^\dagger \frac{\tau_i}{2} \frac{\tau_j}{2} W^{i}_{\mu\nu} W^{\mu\rho\;j} \left\{D_\rho, D^\nu\right\}\Phi + \mathrm{h.c.}\)

\(\mathrm{LAM}^2\)

\(c_{BB}/\Lambda^4\)

'CBBL4'

\(\mathrm{i} \Phi^\dagger B_{\mu\nu} B^{\mu\rho} \left\{D_\rho, D^\nu\right\}\Phi + \mathrm{h.c.}\)

\(\mathrm{LAM}^2\)

\(c_{\tilde BW}/\Lambda^4\)

'CBtWL4'

\(-\mathrm{i} \Phi^\dagger \tilde B_{\mu\nu} \frac{\tau_i}{2} W^{\mu\rho\;i} \left\{D_\rho, D^\nu\right\}\Phi + \mathrm{h.c.}\)

\(\mathrm{LAM}^2\)

The user has to make sure that no corrections other than pure QCD ones are selected. An example for diboson production is given below.

Snippet code

program atgc_warsaw_example
  use recola
  implicit none
  integer, parameter :: dp = kind(23d0)
  real (dp)          :: p(0:3,1:6), pp(0:3,1:4), pdw(0:3,1:3), pdz(0:3,1:3), A2(0:2)
  real (dp)          :: MW, MZ, GW, GZ
  character(len=100) :: modelname
  complex (dp) :: cone
  integer :: i
  parameter ( cone=(1d0,0d0) )

  call set_output_file_rcl('*')

  MW = 8.0349970922628273E+01
  GW = 2.0842988587989093E+00
  MZ = 9.1153480619182758E+01
  GZ = 2.4942663787728243E+00

  call set_output_file_rcl('*')
  call set_complex_mass_scheme_rcl

  call set_mu_ir_rcl(0.5d0*(MW+MZ))
  call set_mu_uv_rcl(0.5d0*(MW+MZ))
  call set_mu_ms_rcl(0.5d0*(MW+MZ))

  call set_light_fermions_rcl(1d-3)
  call set_alphas_rcl(0.118d+00, MZ, 5)

  call set_parameter_rcl("MW", cone*MW)
  call set_parameter_rcl("WW", cone*GW)
  call set_parameter_rcl("MZ", cone*MZ)
  call set_parameter_rcl("WZ", cone*GZ)

  call set_resonant_particle_rcl('W+')
  call set_resonant_particle_rcl('Z')

  call set_parameter_rcl('CWD6',        cone*1.0d-6)
  call set_parameter_rcl('CHBD6',       cone*0.0d-6)
  call set_parameter_rcl('CHWD6',       cone*0.0d-6)
  call set_parameter_rcl('CHWBD6',      cone*0.0d-6)
  call set_parameter_rcl('CWtildeD6',   cone*0.0d-6)
  call set_parameter_rcl('CHBtildeD6',  cone*0.0d-6)
  call set_parameter_rcl('CHWtildeD6',  cone*0.0d-6)
  call set_parameter_rcl('CHWtildeBD6', cone*0.0d-6)

  call set_parameter_rcl('CBWL4',   cone*0.0d0)
  call set_parameter_rcl('CWWL4',   cone*0.0d0)
  call set_parameter_rcl('CBBL4',   cone*0.0d0)
  call set_parameter_rcl('CBtWL4',  cone*0.0d0)


  ! Define process and set coupling orders
  call define_process_rcl(1,'u d~ -> W+(mu+ nu_mu) Z(e+ e-)','NLO')

  call select_power_BornAmpl_rcl(1,'QCD',0)
  call select_power_LoopAmpl_rcl(1,'QCD',2)
  call select_power_BornAmpl_rcl(1,'QED',4)
  call select_power_LoopAmpl_rcl(1,'QED',4)

  ! Generate process
  call generate_processes_rcl

  ! Example phase-space point for process 1
  p(:, 1) = [227.39345312954683d0,  0.0000000000000000d0,  0.0000000000000000d0,  227.39345312954683d0]
  p(:, 2) = [227.39345312954683d0,  0.0000000000000000d0,  0.0000000000000000d0, -227.39345312954683d0]
  p(:, 3) = [42.091253388702761d0,  7.0682379749920559d0,  22.640966407137846d0,  34.772119059840406d0]
  p(:, 4) = [183.26515868246659d0, -29.942025082444019d0, -56.364534205011779d0,  171.79241195327580d0]
  p(:, 5) = [19.329309891962328d0,  12.844761211993173d0, -14.265740621156976d0, -2.2633989564945494d0]
  p(:, 6) = [210.10118429596204d0,  10.029025895458791d0,  47.989308419030905d0, -204.30113205662164d0]

  pp(:, 1) = p(:, 1)
  pp(:, 2) = p(:, 2)
  pp(:, 3) = p(:, 3) + p(:, 4)
  pp(:, 4) = p(:, 5) + p(:, 6)

  write(*,*) "sqrt(pW^2): ", sqrt(pp(0,3)**2 - sum(pp(1:3,3)**2))
  write(*,*) "sqrt(pZ^2): ", sqrt(pp(0,4)**2 - sum(pp(1:3,4)**2))

  pdw(:, 1) = pp(:, 3)
  pdw(:, 2) =  p(:, 3)
  pdw(:, 3) =  p(:, 4)

  pdz(:, 1) = pp(:, 4)
  pdz(:, 2) =  p(:, 5)
  pdz(:, 3) =  p(:, 6)

  ! Compute process and print its results
  call compute_process_rcl(1,p,'NLO')
  call writeResults(1)

  do i=0,2
    call get_squared_amplitude_rcl(pr, [2, 8, i], 'NLO', A2(i))
    write(*,'(A,X,I2,X,A,I1,A,E15.8)') 'A2 for process', pr, '(lam = -', i, ') = ', A2(i)
  end do

  call reset_recola_rcl
end program atgc_warsaw_example

Releases

References

HLP+25

Ulrich Haisch, Jakob Linder, Giovanni Pelliccioli, Emanuele Re, and Giulia Zanderighi. Polarized-boson pairs at NLO in the SMEFT. JHEP, 11:080, 2025. arXiv:2507.21768, doi:10.1007/JHEP11(2025)080.