MSSM Calculator

Hi:
    After checking, I think the difference between the calculation using different cards is due to the width of higgs. In my feeling, MadGraph only read the width of the particle and ignore the branching ratio listed in the param_card. For my case, all other part of the param_card are nearly the same(only a little difference), expect the width of the higgs in MSSM(h H A H+ H-) , and my process contains one higgs decaying into b b~, so the difference seems come from the width of higgs.

The Card calculated using online calculator: ( Cards-I )
===================================================================
........
#
# PDG Width
DECAY 25 2.12453531E-03 # h decays
# BR NDA ID1 ID2
     1.27587787E-01 2 15 -15 # BR(H1 -> tau- tau+)
     6.70754493E-01 2 5 -5 # BR(H1 -> b bb)
     1.83439788E-01 2 24 -24 # BR(H1 -> W+ W-)
     1.82179317E-02 2 23 23 # BR(H1 -> Z Z)
#
.........
====================================================================

The Card calculated using SUSY-HIT: (Cards-II)
====================================================================
........
#
# PDG Width
DECAY 25 4.28863092E-03 # h decays
# BR NDA ID1 ID2
     6.46190317E-01 2 5 -5 # BR(h -> b bb )
     6.29717349E-02 2 -15 15 # BR(h -> tau+ tau- )
     2.22899101E-04 2 -13 13 # BR(h -> mu+ mu- )
     4.72514531E-04 2 3 -3 # BR(h -> s sb )
     1.96357091E-02 2 4 -4 # BR(h -> c cb )
     5.69544985E-02 2 21 21 # BR(h -> g g )
     2.22914170E-03 2 22 22 # BR(h -> gam gam )
     1.38791413E-03 2 22 23 # BR(h -> Z gam )
     1.83883981E-01 2 24 -24 # BR(h -> W+ W- )
     2.27949114E-02 2 23 23 # BR(h -> Z Z )
     3.25637868E-03 2 1000022 1000022 # BR(h -> ~chi_10 ~chi_10)
#
........
==================================================================

If I generate h1 > b b~ in mssm-full and using the (Cards-II) as input
the result Width for this channel is:
0.001425GeV

so the branching ratio drop from 64.6% to 33.2%, which could explain the difference between the CS using these two cards for my process.

I'm not sure whether it is the case. How could I get the correct CS?

So your latest result 0.001425GeV is coherent with the value of the online calculator:2.12453531E-03 *6.70754493E-01= 0.0014250416047196478.

When the one obtain by SUSY-Hit is not coherent:
4.28863092E-03 * 6.46190317E-01 = 0.002771271773690801

So I would be suspecious about the the SUSY-HIT result.
On the other hand they include loop-contribution (like h1>a a ) which seems missing in the online one.
So this explains part of the difference.

Cheers,

Olivier

Hi:
     So for this moment, if I scale the cross section using card-II by a factor of Higgs width in Card-II divided by the Higgs width in Card-I ( 4.2886 / 2.1245 ~ 2.0186), Is the result make sense?

Best

Teddy

Oh~ In my process, there is only one Higgs.

Best

Teddy

Oh~ In my process, there is only one Higgs.

Best

Teddy

 By doing this you assume the Narrow width approximation which is certainly fine in this case.

So yes.

Cheers,

Olivier

Thanks very much!

Teddy