Generation of q q > z h [QCD], with q = u d c s b, 'Fatal error in set_tau_min'

Hi,

You can not have massive initial state at NLO (it does not technically make sense at LO either even if some people argue that it help for the hadronisation model).
If you want to perform a five flavor computation, then you need to set the bmass to zero.

To be fully consistent, the b mass should be set to zero at the model level.
i.e. you need to do
import model sm-no_b_mass
generate p p > Z h [QCD]

You do not need to specify that “p” contains the b quark since this is automatic now.
(if you do not see this behavior this is likely that you are using a very old version of the code)

Cheers,

Olivier

> On Nov 11, 2016, at 13:22, David Englert <email address hidden> wrote:
>
> New question #403986 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/403986
>
> Dear MadGraph experts,
>
> I am trying to generate events for the following process:
> 'q q > z h [QCD]', where 'q = u c d s u~ c~ d~ s~ b b~' .
>
> I run with default options (no fix order, etc.). However the calculation fails for the 'P0_bbx_zh' and 'P0_bxb_zh' parts, and the error seems to related to tau ("Fatal error in set_tau_min").
>
> I pasted below the tail of the stdout message and a P0_bbx_zh the log file.
>
> I manage to run the calculation without any problems by excluding the b quark from the definition of 'q'. I assume that adding the b quark to the set of initial state particles is not going to change the total cross section much, but I added it for consistency reason as I compare the SM result to a BSM model where the processes with b quark initial state can be relevant.
>
> Any idea what goes wrong here?
>
> thanks,
> David
>
> #############################
> ### --- Tail of std output messages --- ###
> #############################
>
> Error detected in "launch auto "
> write debug file /home/de3u14/lib/build/hep/MadGraph/MG5_aMC_v2_4_2/test/run_01_tag_1_debug.log
> If you need help with this issue please contact us on https://answers.launchpad.net/mg5amcnlo
> aMCatNLOError : An error occurred during the collection of results.
> Please check the .log files inside the directories which failed:
> /home/de3u14/lib/build/hep/MadGraph/MG5_aMC_v2_4_2/test/SubProcesses/P0_bbx_zh/GF1/log.txt
> /home/de3u14/lib/build/hep/MadGraph/MG5_aMC_v2_4_2/test/SubProcesses/P0_bbx_zh/GF2/log.txt
> /home/de3u14/lib/build/hep/MadGraph/MG5_aMC_v2_4_2/test/SubProcesses/P0_bbx_zh/GF3/log.txt
> /home/de3u14/lib/build/hep/MadGraph/MG5_aMC_v2_4_2/test/SubProcesses/P0_bxb_zh/GF1/log.txt
> /home/de3u14/lib/build/hep/MadGraph/MG5_aMC_v2_4_2/test/SubProcesses/P0_bxb_zh/GF2/log.txt
> /home/de3u14/lib/build/hep/MadGraph/MG5_aMC_v2_4_2/test/SubProcesses/P0_bxb_zh/GF3/log.txt
>
> ########################################################################################
> ### --- Contents of /home/de3u14/lib/build/hep/MadGraph/MG5_aMC_v2_4_2/test/SubProcesses/P0_bbx_zh/GF1/log.txt --- ###
> #######################################################################################
>
> ===============================================================
> INFO: MadFKS read these parameters from FKS_params.dat
> ===============================================================
>> IRPoleCheckThreshold = 1.0000000000000001E-005
>> PrecisionVirtualAtRunTime = 1.0000000000000000E-003
>> NHelForMCoverHels = 4
>> VirtualFraction = 1.0000000000000000
>> MinVirtualFraction = 5.0000000000000001E-003
> ===============================================================
> A PDF is used, so alpha_s(MZ) is going to be modified
> Old value of alpha_s from param_card: 0.11799999999999999
> ****************************************
>
> NNPDFDriver version 1.0.3
> Grid: NNPDF23nlo_as_0119_qed_mem0.grid
> ****************************************
> New value of alpha_s from PDF nn23nlo: 0.11899999999999999
> *****************************************************
> * MadGraph/MadEvent *
> * -------------------------------- *
> * http://madgraph.hep.uiuc.edu *
> * http://madgraph.phys.ucl.ac.be *
> * http://madgraph.roma2.infn.it *
> * -------------------------------- *
> * *
> * PARAMETER AND COUPLING VALUES *
> * *
> *****************************************************
>
> External Params
> ---------------------------------
>
> MU_R = 91.188000000000002
> aEWM1 = 132.50700000000001
> mdl_Gf = 1.1663900000000000E-005
> aS = 0.11799999999999999
> mdl_ymb = 4.7000000000000002
> mdl_ymt = 173.00000000000000
> mdl_ymtau = 1.7769999999999999
> mdl_MT = 173.00000000000000
> mdl_MB = 4.7000000000000002
> mdl_MZ = 91.188000000000002
> mdl_MH = 125.00000000000000
> mdl_MTA = 1.7769999999999999
> mdl_WT = 1.4915000000000000
> mdl_WZ = 2.4414039999999999
> mdl_WW = 2.0476000000000001
> mdl_WH = 6.3823389999999999E-003
> Internal Params
> ---------------------------------
>
> mdl_conjg__CKM3x3 = 1.0000000000000000
> mdl_CKM22 = 1.0000000000000000
> mdl_lhv = 1.0000000000000000
> mdl_CKM3x3 = 1.0000000000000000
> mdl_conjg__CKM22 = 1.0000000000000000
> mdl_conjg__CKM33 = 1.0000000000000000
> mdl_Ncol = 3.0000000000000000
> mdl_CA = 3.0000000000000000
> mdl_TF = 0.50000000000000000
> mdl_CF = 1.3333333333333333
> mdl_complexi = ( 0.0000000000000000 , 1.0000000000000000 )
> mdl_MZ__exp__2 = 8315.2513440000002
> mdl_MZ__exp__4 = 69143404.913893804
> mdl_sqrt__2 = 1.4142135623730951
> mdl_MH__exp__2 = 15625.000000000000
> mdl_Ncol__exp__2 = 9.0000000000000000
> mdl_MB__exp__2 = 22.090000000000003
> mdl_MT__exp__2 = 29929.000000000000
> mdl_aEW = 7.5467711139788835E-003
> mdl_MW = 80.419002445756163
> mdl_sqrt__aEW = 8.6872153846781555E-002
> mdl_ee = 0.30795376724436879
> mdl_MW__exp__2 = 6467.2159543705357
> mdl_sw2 = 0.22224648578577766
> mdl_cw = 0.88190334743339216
> mdl_sqrt__sw2 = 0.47143025548407230
> mdl_sw = 0.47143025548407230
> mdl_g1 = 0.34919219678733299
> mdl_gw = 0.65323293034757990
> mdl_v = 246.21845810181637
> mdl_v__exp__2 = 60623.529110035903
> mdl_lam = 0.12886910601690263
> mdl_yb = 2.6995554250465490E-002
> mdl_yt = 0.99366614581500623
> mdl_ytau = 1.0206617000654717E-002
> mdl_muH = 88.388347648318430
> mdl_AxialZUp = -0.18517701861793787
> mdl_AxialZDown = 0.18517701861793787
> mdl_VectorZUp = 7.5430507588273299E-002
> mdl_VectorZDown = -0.13030376310310560
> mdl_VectorAUp = 0.20530251149624587
> mdl_VectorADown = -0.10265125574812294
> mdl_VectorWmDxU = 0.23095271737156670
> mdl_AxialWmDxU = -0.23095271737156670
> mdl_VectorWpUxD = 0.23095271737156670
> mdl_AxialWpUxD = -0.23095271737156670
> mdl_I1x33 = ( 2.6995554250465490E-002, 0.0000000000000000 )
> mdl_I2x33 = ( 0.99366614581500623 , 0.0000000000000000 )
> mdl_I3x33 = ( 0.99366614581500623 , 0.0000000000000000 )
> mdl_I4x33 = ( 2.6995554250465490E-002, 0.0000000000000000 )
> mdl_Vector_tbGp = (-0.96667059156454072 , 0.0000000000000000 )
> mdl_Axial_tbGp = ( -1.0206617000654716 , -0.0000000000000000 )
> mdl_Vector_tbGm = ( 0.96667059156454072 , 0.0000000000000000 )
> mdl_Axial_tbGm = ( -1.0206617000654716 , -0.0000000000000000 )
> mdl_gw__exp__2 = 0.42671326129048615
> mdl_cw__exp__2 = 0.77775351421422245
> mdl_ee__exp__2 = 9.4835522759998875E-002
> mdl_sw__exp__2 = 0.22224648578577769
> mdl_yb__exp__2 = 7.2875994928982540E-004
> mdl_yt__exp__2 = 0.98737240933884918
> Internal Params evaluated point by point
> ----------------------------------------
>
> mdl_sqrt__aS = 0.34351128074635334
> mdl_G__exp__4 = 2.1987899468922913
> mdl_G__exp__2 = 1.4828317324943823
> mdl_R2MixedFactor_FIN_ = -2.5040377713124864E-002
> mdl_GWcft_UV_b_1EPS_ = -3.1300472141406080E-003
> mdl_GWcft_UV_t_1EPS_ = -3.1300472141406080E-003
> mdl_bWcft_UV_1EPS_ = -1.8780283284843650E-002
> mdl_tWcft_UV_1EPS_ = -1.8780283284843650E-002
> mdl_bMass_UV_1EPS_ = ( 0.0000000000000000 , 0.17653466287753031 )
> mdl_UV_yuk_b_1EPS_ = -3.7560566569687301E-002
> mdl_G__exp__3 = 1.8056676068262196
> mdl_MU_R__exp__2 = 8315.2513440000002
> mdl_GWcft_UV_b_FIN_ = -1.8563438626678915E-002
> mdl_GWcft_UV_t_FIN_ = 4.0087659331150384E-003
> mdl_bWcft_UV_FIN_ = -0.13642100947319838
> mdl_tWcft_UV_FIN_ = -9.8778211443463623E-004
> mdl_bMass_UV_FIN_ = ( 0.0000000000000000 , 1.2823574890480649 )
> mdl_UV_yuk_b_FIN_ = -0.27284201894639676
> Couplings of loop_sm
> ---------------------------------
>
> UV_bMass = 0.00000E+00 0.12824E+01
> UVWfct_b_0 = -0.13642E+00 -0.00000E+00
> R2_DDZ_V2 = 0.00000E+00 0.72127E-02
> R2_UUZ_V2 = -0.00000E+00 -0.72127E-02
> R2_UUZ_V5 = 0.00000E+00 0.68702E-03
> R2_bbH = 0.00000E+00 0.95598E-03
> UV_Hbb_1eps = 0.00000E+00 0.71698E-03
> UV_Hbb = 0.00000E+00 0.52082E-02
> GC_5 = 0.00000E+00 0.12177E+01
> R2_QQq = 0.00000E+00 0.12520E-01
> R2_QQb = 0.00000E+00 0.11769E+00
> UV_bMass_1eps = 0.00000E+00 0.17653E+00
> UVWfct_b_0_1eps -0.18780E-01 0.00000E+00
> GC_21 = -0.00000E+00 -0.28804E+00
> GC_22 = 0.00000E+00 0.28804E+00
> GC_23 = -0.00000E+00 -0.27437E-01
> GC_32 = 0.00000E+00 0.67544E+02
> GC_33 = -0.00000E+00 -0.19089E-01
>
> Collider parameters:
> --------------------
>
> Running at P P machine @ 13000.000000000000 GeV
> PDF set = nn23nlo
> alpha_s(Mz)= 0.1190 running at 2 loops.
> alpha_s(Mz)= 0.1190 running at 2 loops.
> Renormalization scale set on event-by-event basis
> Factorization scale set on event-by-event basis
>
>
> Diagram information for clustering has been set-up for nFKSprocess 1
> Diagram information for clustering has been set-up for nFKSprocess 2
> Diagram information for clustering has been set-up for nFKSprocess 3
> Diagram information for clustering has been set-up for nFKSprocess 4
> getting user params
> Enter number of events and iterations:
> Number of events and iterations -1 12
> Enter desired fractional accuracy:
> Desired fractional accuracy: 2.9999999999999999E-002
> Enter alpha, beta for G_soft
> Enter alpha<0 to set G_soft=1 (no ME soft)
> for G_soft: alpha= 1.0000000000000000 , beta= -0.10000000000000001
> Enter alpha, beta for G_azi
> Enter alpha>0 to set G_azi=0 (no azi corr)
> for G_azi: alpha= -1.0000000000000000 , beta= -0.10000000000000001
> Doing the S and H events together
> Suppress amplitude (0 no, 1 yes)?
> Using suppressed amplitude.
> Exact helicity sum (0 yes, n = number/event)?
> Do MC over helicities for the virtuals
> Enter Configuration Number:
> Running Configuration Number: 1
> Enter running mode for MINT:
> 0 to set-up grids, 1 to integrate, 2 to generate events
> MINT running mode: 0
> Set the three folding parameters for MINT
> xi_i, phi_i, y_ij
> 1 1 1
> 'all ', 'born', 'real', 'virt', 'novi' or 'grid'?
> Enter 'born0' or 'virt0' to perform
> a pure n-body integration (no S functions)
> doing the all of this channel
> Normal integration (Sfunction != 1)
> Not subdividing B.W.
> about to integrate 7 -1 12 1
> imode is 0
> ------- iteration 1
> Update # PS points (even): 560 --> 512
> Using random seed offsets: 1 , 5 , 0
> with seed 34
> Ranmar initialization seeds 13168 9413
> Total number of FKS directories is 4
> FKS process map (sum= 3 ) :
> 1 --> 2 : 1 3
> 2 --> 2 : 2 4
> ================================
> process combination map (specified per FKS dir):
> 1 map 1
> 1 inv. map 1
> 2 map 1
> 2 inv. map 1
> 3 map 1
> 3 inv. map 1
> 4 map 1
> 4 inv. map 1
> ================================
> nFKSprocess: 1. Absolute lower bound for tau at the Born is 0.27655E-03 0.21619E+03 0.13000E+05
> nFKSprocess: 1. Lower bound for tau is 0.27655E-03 0.21619E+03 0.13000E+05
> nFKSprocess: 1. Lower bound for tau is (taking resonances into account) 0.27655E-03 0.21619E+03 0.13000E+05
> nFKSprocess: 2. Absolute lower bound for tau at the Born is 0.27655E-03 0.21619E+03 0.13000E+05
> nFKSprocess: 2. Lower bound for tau is 0.27655E-03 0.21619E+03 0.13000E+05
> nFKSprocess: 2. Lower bound for tau is (taking resonances into account) 0.27655E-03 0.21619E+03 0.13000E+05
> nFKSprocess: 3. Absolute lower bound for tau at the Born is 0.27655E-03 0.21619E+03 0.13000E+05
> nFKSprocess: 3. Lower bound for tau is 0.27655E-03 0.21619E+03 0.13000E+05
> nFKSprocess: 3. Lower bound for tau is (taking resonances into account) 0.27655E-03 0.21619E+03 0.13000E+05
> nFKSprocess: 4. Absolute lower bound for tau at the Born is 0.27655E-03 0.21619E+03 0.13000E+05
> nFKSprocess: 4. Lower bound for tau is 0.27655E-03 0.21619E+03 0.13000E+05
> nFKSprocess: 4. Lower bound for tau is (taking resonances into account) 0.27655E-03 0.21619E+03 0.13000E+05
> Mass shell violation [nocms]
> j= 1
> mass= 4.7000000000000002
> mass computed= 0.0000000000000000
> 0.11914775D+03 0.00000000D+00 0.00000000D+00 0.11914775D+03
> Mass shell violation [nocms]
> j= 1
> mass= 4.7000000000000002
> mass computed= 0.0000000000000000
> 0.11872648D+03 0.00000000D+00 0.00000000D+00 0.11872648D+03
> bpower is 0.0000000000000000
> Mass shell violation [nocms]
> j= 1
> mass= 4.7000000000000002
> mass computed= 0.0000000000000000
> 0.11914775D+03 0.00000000D+00 0.00000000D+00 0.11914775D+03
> Mass shell violation [nocms]
> j= 1
> mass= 4.7000000000000002
> mass computed= 0.0000000000000000
> 0.11872648D+03 0.00000000D+00 0.00000000D+00 0.11872648D+03
> Fatal error in set_tau_min
> Time in seconds: 0
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.