[Sane-analysis] Neat result Re: Update to inclusive pions wiki section

[O. A. Rondon]

I  got a neat result when plotting the Yerevan data vs pion transverse
momentum PT. As it should have been expected, it scales very well,
following the decaying exponential dependence of all inclusive high
energy data, regardless of incident beam or detected particle, see
discussion here
https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Scaling_fits_to_Hall_C_positron_data

So I have replaced the plot comparing epc_or vs the Yerevan data to show
the results both vs pion p and pion PT. The epc correction shown is
still of the form a + b*angle^2. A fit of the form a + b*sin(angle)
gives similar, but a bit worse results, so I didn't include it
https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Inclusive_pion_and_nucleon_electroproduction


Cheers,

Oscar




O. A. Rondon wrote:
> I have updated my wiki section on Inclusive pion and nucleon
> electroproduction adding an empirical correction to the epc code output
> for high momentum inclusive pion electro- and photo-production on C nuclei.
> 
> I added a pion angle dependent normalization to minimize the chi squared
> between the epc code output and the Yerevan 4.5 GeV pion photoproduction
>  on C data, see item *Empirical modification of epc output* at
> 
> https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Inclusive_pion_and_nucleon_electroproduction
> 
> The fit is
> epc_corrected = epc_output*(a + b*angle^2), a=.171, b=.53, angle in
> radians.
> 
> The data vs epc_corrected agreement is better than 20% for 40
> deg., and smaller than a factor of 1.5 for most other points. The two
> high p points for 60 deg. didn't improve
> 
> Since the data values come from digitized points from the published
> plots they don't include errors, so the chi squared is a pseudo-chi
> squared calculated as the squared ratio of the difference over the sum
> of the data minus the epc output.
> 
> Given the strong angle dependence of the normalization I would not
> recommend using other overall angle-independent normalizations, such as
> the form A^.8, which is of unknown origin and ambiguous on how to use
> (normalize pion production on H by A^.8? how about production on
> neutrons? normalize to 2H?) Keep in mind that epc does calculate nuclear
> cross sections already.
> 
> Cheers,
> 
> Oscar
> 
> 
> 
> 
> 
>