# Quark Matter 2017

Feb 5 – 11, 2017
Hyatt Regency Chicago
America/Chicago timezone

## Constituent quarks and systematic errors in midrapidity charged multiplicity ($dN_{\rm ch}/d\eta$) distributions.

Not scheduled
2h 30m
Hyatt Regency Chicago

#### Hyatt Regency Chicago

151 East Wacker Drive Chicago, Illinois, USA, 60601
Board: L09
Poster

### Speaker

Michael Tannenbaum (Brookhaven National Laboratory (US))

### Description

Although it was demonstrated more than 13 years ago that the
increase in midrapidity $dN_{\rm ch}/d\eta$ with increasing centrality
of Au+Au collisions at RHIC was linearly proportional to the number
of constituent quark participants ($N_{qp}$) in the collision,
it was only in the last few years that generating the spatial positions of the
three quarks in a nucleon according to the Fourier transform of the measured electric
charge form factor of the proton could be used to connect $dN_{\rm ch}/d\eta/N_{qp}$ as a function
of centrality in p(d)$+$A and A$+$A collisions with the same value of $dN_{\rm ch}/d\eta/N_{qp}$
determined in p$+$p collisions. The several calculations had slightly different methods.
One calculation, which only compared its calculated
$dN_{\rm ch}/d\eta/N_{qp}$ in p$+$p at $\sqrt{s_{NN}}=200$ GeV to the least central of 12 centrality
bin measurements in Au$+$Au by PHENIX, claimed that the p$+$p value was higher by about 30\%'' from
the band of measurements vs. centrality and suggested a smaller number of subnuclear contributors, e.g. quark-diquark. However the clearly quoted systematic errors were ignored for which a 1 standard deviation systematic shift would move all the 12 Au$+$Au data points to within 1.3 standard deviations of the p$+$p value, or if the statistical and systematic errors are added in quadrature a difference of 35 $\pm$ 21\% .
The PHENIX method gives a difference of 19$\pm$18\%.

Collaboration Not applicable Initial State Physics and Approach to Equilibrium

### Primary author

Michael Tannenbaum (Brookhaven National Laboratory (US))

### Presentation materials

There are no materials yet.