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* Implementation of MNR calculations                                   *
* [M. Mangano, P. Nason and G. Ridolfi, Nucl. Phys. B 373 (1992) 295]. *
* Author: Oleksandr Zenaiev (oleksandr.zenaiev@desy.de)                *
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The basic idea is to replace Monte Carlo integration over phase space (used
in the original MNR code, available at www.ge.infn.it/~ridolfi/hvqlibx.tgz) 
by the trapezoidal rule in nested loops (implemented here). This allows 
for separation of the most time consuming parts in the top loop(s). 
The one-particle inclusive variant of the calculations was used. 
Additionally non-perturbative quark -> parton fragmentation is implemented 
(including most popular Kartvelishvili, Peterson and BCFY functions). 
All flexibility of the original MNR code was retained: the factorisation 
and renormalisation scales, heavy-quark mass, strong coupling constant, 
fragmentation function and PDFs may be changed in each iteration 
(in other words, may be treated as fit parameters). The typical timing 
to calculate one set of the predictions is ∼ 1 s and the inaccuracy of 
the predictions is less than 1% comparing to the results obtained with 
the original MNR code. Additionally the results were cross checked with 
the NLO predictions as calculated by the (semi)independent FONLL program, 
using the public web interface http://cacciari.web.cern.ch/cacciari/fonll, 
and differences were found to be within 1-3%.

As an example how to use this calculation for your dataset, see routines 
hvqmnr_lhcb_7tev_charm_() and hvqmnr_lhcb_7tev_beauty_() 
in src/hvqmnr_calculation.cxx and datasets in 
datafiles/lhc/lhcb/charmProduction/1302.2864 and 
datafiles/lhc/lhcb/beautyProduction/1306.3663.
Be especially carefull with parameters in HVQMNR::Steering, since they 
determine accuracy of calculations. It is strongly recommended to cross 
check results vs. other source, e.g.:
1) original MNR code from www.ge.infn.it/~ridolfi/hvqlibx.tgz 
2) public FONLL web interface http://cacciari.web.cern.ch/cacciari/fonll
   (remember to choose 'NLO' option there)

Further information can be found in:
1) DESY-THESIS-2015-012 (Chapter 7 and Appendix F)
2) Slides: https://indico.cern.ch/event/377706/contribution/1/attachments/753331/1033438/OZ_pdffit_2015.03.03.pdf
