Based on mc_hms_single.f
Source code:
/u/group/hallc_ana/xem/xiaochao/code_johna/mc_hms/mc_hms_elastic.f
What has been/needs to be done
    1. Add Ebeam, Ztarg, Atarg in input file;
    2. Add intrad() for internal radiative corrections (before/after);
    3. Update target information -- at least for LH2 target; need to add more;
    4. Add in elastic cross section for protons using Bosted fit; need to try more form factor fits';
    5. Code is working, but to test it, need data to compare with.