https://doi.org/10.1140/epjc/s10052-020-8201-6
Regular Article - Experimental Physics
From prompt to direct 
production: new insights on the 
and 
polarizations and feed-down contributions from a global-fit analysis of mid-rapidity LHC data
1
LIP, Lisbon, Portugal
2
CERN, Geneva, Switzerland
3
DESY, Hamburg, Germany
* e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
** e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
Received:
12
May
2020
Accepted:
3
July
2020
Published online:
14
July
2020
Abstract
While the prompt cross section and polarization have been measured with good precision as a function of transverse momentum, 
, those of the directly produced are practically unknown, given that the cross sections and polarizations of the and mesons, large indirect contributors to production, are only known with rather poor accuracy. The lack of precise measurements of the 
polarizations induces large uncertainties in the level of their feed-down contributions to the prompt yield, because of the polarization-dependent acceptance corrections. The experimental panorama of charmonium production can be significantly improved through a consistent and model-independent global analysis of existing measurements of , 
and 
cross sections and polarizations, faithfully respecting all the correlations and uncertainties. In particular, it is seen that the polarizations and feed-down fractions to production have a negligible dependence on the
, with average values 
, 
, 
and 
. The analysis also shows that 
% of the prompt yield is due to directly-produced mesons, of polarization constrained to remarkably small values, 
.
© The Author(s), 2020
