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Including Restrictions

Posted: 20. Jul 2016, 16:38
by brabachu
Hi,

I was wondering what the proper way to use a restriction_XXXX.dat with MadGraph and a Spheno.spc.Model file. Following the procedure outlined in https://answers.launchpad.net/mg5amcnlo ... ion/227597, it first tells me to generate a param_card.dat using write_param_card.py. Then I can make this into my restriction file if I rename it and give it whatever restrictions i want. However I am interested in giving restrictions to matrix inputs that are only generated after I run SPheno, for example Ye, the Yukawa matrix in the SARA SM model file.

I am trying to do this to reduce the number of diagrams MadGraph generates. For a simple process 'generate u u > u u h', the SARAH SM gives me much more diagrams than default MadGraph. The probably have negligible contributions to the cross section in the end but it increases the run time.

Thanks!

Re: Including Restrictions

Posted: 21. Jul 2016, 10:57
by FStaub
Hi,

can't you take the SPheno spc file and edit it my hand in order to put everything to zero what you want to neglect and load it then as restriction file?

Cheers,
Florian

Re: Including Restrictions

Posted: 21. Jul 2016, 13:27
by Guest
I tried that but I get the following error:

Code: Select all

MadGraph5Error : Invalid restriction card (not same block)
	    set(['mnr', 'fwcoef', 'gauge', 'uulmix', 'zmix', 'effhiggscouplings', 'mchi', 'decay', 'minpar', 'flavorkitqfv', 'uvmix', 'sphenolowenergy', 'imfwcoef', 'uelmix', 'spheno', 'imzmix', 'treesm', 'ye', 'yd', 'modsel', 'sminputs', 'yu', 'gaugegut', 'uurmix', 'udlmix', 'udrmix', 'mass', 'sm', 'uermix', 'flavorkitlfv', 'hdm', 'loopsm', 'hmix']) != set(['imuelmix', 'imuurmix', 'uulmix', 'zmix', 'effhiggscouplings', 'imhdm', 'decay', 'imudlmix', 'imuulmix', 'imuermix', 'uvmix', 'imuvmix', 'ychil', 'uelmix', 'imudrmix', 'imzmix', 'sminputs', 'ychir', 'uurmix', 'udlmix', 'imychir', 'imynu', 'udrmix', 'imychil', 'mass', 'uermix', 'ynu', 'hdm']).
	    Missing block: imuvmix,ychil,imuelmix,imhdm,imuurmix,imudrmix,imudlmix,imychir,imynu,imychil,imuulmix,imuermix,ynu,ychir
	    Unknown block : treesm,mchi,gaugegut,imfwcoef,spheno,ye,mnr,minpar,fwcoef,flavorkitqfv,yd,gauge,sm,loopsm,flavorkitlfv,modsel,yu,sphenolowenergy,hmix
Do you have any suggestions on how to fix this? I am not sure if I should edit the model_reader.py file

Re: Including Restrictions

Posted: 21. Jul 2016, 14:12
by FStaub
Sorry, but I have no idea why this error appears. Since the SLHA file is accepted as param_card when generating events, it sounds to me like a bug in the reader of the restriction card.

Re: Including Restrictions

Posted: 21. Jul 2016, 14:21
by brabachu
Ok thank you for the assistance!

Re: Including Restrictions

Posted: 22. Jul 2016, 16:59
by brabachu
Hi,

I was wondering if this would be an easier question to ask. Using the SM model file that came with SARAH, I did the usual procedure MakeAll, copy the UFO outputs to a file in MadGraph models/SM/* , copied the required files to SPheno, generated a SPheno.spc.SM file.

Do you know how to place restrictions on this model? This also generates more diagrams than necessary since it does not know off hand that the Yukawa matrix is diagonal. Maybe if I can see how this is done I can extend it to my model.

Thanks!

Re: Including Restrictions

Posted: 22. Jul 2016, 21:14
by FStaub
Sorry, but I can't say anything because I never tried that option of MG myself.

Florian

Re: Including Restrictions

Posted: 18. Aug 2016, 11:49
by brabachu
Hi,

I just wanted to post the solution to this in case anyone ever needs it (at least the way I got it to work):

The SPheno.spc.Model file can't be used as a restriction card. If you want to make a restriction card, you need to go into the UFO output and do

$ python write_param_card.py

Then rename the 'param_card.dat' generated to 'restrict_Model.dat'. To get rid of all the extra diagrams set the quark masses to 0 (or 1e-99), or any other coupling that you might want to set to zero. Then load the restriction card as usual. See https://cp3.irmp.ucl.ac.be/projects/mad ... ls/USERMOD for more details on what you can do with this restriction card.

I hope this makes sense.


Best,
Brad

Re: Including Restrictions

Posted: 18. Aug 2016, 12:07
by FStaub
Thank you for sharing the information!