Missing processes for indirect detection

Asked by Zhao-Huan Yu

Hi,

I am using MadDM for studying relic abundance and indirect detection.

In my model, there are three CP-even neutral Higgs bosons (h1, h2, h3), one CP-odd neutral Higgs boson (ha), and a pair of charged Higgs bosons (hp, hm).

I find that the directory matrix_elements/ contains the following fortran codes for 16 annihilation processes related to relic abundance:
matrix_1999_chichi_bbx.f
matrix_1999_chichi_h1h1.f
matrix_1999_chichi_h1h2.f
matrix_1999_chichi_h1h3.f
matrix_1999_chichi_h2h2.f
matrix_1999_chichi_h2h3.f
matrix_1999_chichi_h3h3.f
matrix_1999_chichi_haha.f
matrix_1999_chichi_hphm.f
matrix_1999_chichi_hpwm.f
matrix_1999_chichi_tamtap.f
matrix_1999_chichi_ttx.f
matrix_1999_chichi_wphm.f
matrix_1999_chichi_wpwm.f
matrix_1999_chichi_zha.f
matrix_1999_chichi_zz.f

On the other hand, the directory Indirect/SubProcesses only contains the following directories for 11 annihilation processes related to indirect detection:
P1995_chichi_bbx/
P1995_chichi_h1h1/
P1995_chichi_h2h2/
P1995_chichi_h2h3/
P1995_chichi_h3h3/
P1995_chichi_haha/
P1995_chichi_hphm/
P1995_chichi_tamtap/
P1995_chichi_ttx/
P1995_chichi_wpwm/
P1995_chichi_zz/

Thus, it seems that 5 annihilation processes are missing when calculating indirect detection. They are
chichi_h1h2
chichi_h1h3
chichi_hpwm
chichi_wphm
chichi_zha

I have also noticed that when generate the processes for indirect detection, h1 is identified as an SM particle, while h2, h3, ha, hp, hm are identified as BSM particles. Then the generated annihilation processes contain either two SM particles or two BSM particles in the final state. The final states in the above missing processes contain one SM particle and one BSM particle. I think they have been somehow neglected.

Thanks!

Best regards,
Zhao-Huan

Question information

Language:
English Edit question
Status:
Solved
For:
MadDM Edit question
Assignee:
Chiara Arina Edit question
Solved by:
Olivier Mattelaer
Solved:
Last query:
Last reply:
Revision history for this message
Olivier Mattelaer (olivier-mattelaer) said :
#1

Hi,

The final states in the above missing processes contain one SM particle and one BSM particle. I think they have been somehow neglected.

I can confirm that this is exactly what the code does.
we check all the following final states:
            final_states = ['bsm bsm','q_mdm q_mdm','21 21', '5 -5', '6 -6', '22 22', '23 23', '24 -24','25 25', '11 -11', '13 -13', '15 -15', '12 -12', '14 -14', '16 -16']

since h1 has the pdg code of the standard model Higgs it is assume to be standard model, you should use another pdg code if this is not the sm Higgs.

Cheers,

Olivier

PS: I have assigned this to chiara who can comment on the physics (I have no clue of the physics of MadDM)

Revision history for this message
Chiara Arina (carina) said :
#2

Hi,

if you want to include the missing final states into the indirect detection annihilations you can modify the final_states list that Olivier listed above, by including the BSM - SM process.

I won't do it in general in the code yet because I think this is kind of very model dependent. In general you don't expect to have at present day particles other than the SM ones and the dark matter. All the BSM states heavier that the dark matter with the same parity should be gone. However I don't know the exact details of your model, so if you think we are missing some processes in the indirect detection part, please include them modifying the related python code.

best

Chiara

Revision history for this message
Best Olivier Mattelaer (olivier-mattelaer) said :
#3

Hi,

If you want to hack the code, the line that I mention is line 1053 of the file maddm_interface.py
This being said, you can force the code to add such channel by doing
add indirect_detection h1 h2

Cheers,

Olivier

Revision history for this message
Zhao-Huan Yu (yzhxxzxy) said :
#4

Thanks Olivier Mattelaer, that solved my question.

Revision history for this message
Zhao-Huan Yu (yzhxxzxy) said :
#5

Hi Chiara,

Actually, there could be DM annihilation into a BSM particle and an SM particle in many DM models. For instance, the Higgs sector in the MSSM includes two CP-even Higgs boson, one CP-odd Higgs boson and a pair of charged Higgs bosons, and they all have even R-parity. One of the CP-even Higgs bosons must be SM-like, but the other Higgs bosons should be treated as BSM particles.

Some of these Higgs bosons could be light enough to be produced in DM annihilation, along with a SM particle. In such a case, PPPC4DMID cannot provide gamma-ray or cosmic-ray spectrum for these processes, so PYTHIA is essentially important to give the correct result for indirect detection.

This is not a very special example. I hope you could consider to generally include the BSM-SM processes in the code.

Thanks a lot!

Best regards,
Zhao-Huan