What function can be used to fit to a pt-distribution?

Newbie
1

Dear Root community,

Does anyone happen to know what function type can be fitted to a pt- distributions such as the following:ap_vs_sp_ranges_10M.pdf (47.7 KB)

Best regards,

Loek Meijers

2

Try a_0*pow(pt, a_1)/pow(1.+(sqrt(pt*pt+m*m) - a_2)/a_3, a_4), where a_0, …, a_4 are fit parameters