# Imprint of Nucleon Radius on the Slowly Rotating Neutron Star Properties

## TL;DR

This study investigates how the free space nucleon radius influences nuclear matter and neutron star properties, revealing that nucleon size affects observable neutron star characteristics within certain radius limits.

## Contribution

It introduces a modified relativistic mean field model incorporating nucleon radius effects with improved symmetric nuclear matter predictions.

## Key findings

- Nucleon radius up to 0.83 fm remains compatible with nuclear matter properties.
- Nucleon size impacts neutron star radius, moment of inertia, and crust features.
- Nucleon radius effects are imprinted in observable neutron star properties.

## Abstract

We have studied the effect of free space nucleon radius on the nuclear matter and slowly rotating neutron star properties within a relativistic mean field model with the inclusion of omega-rho mixing nonlinear term. We use the same density dependent radius as in our previous work. However, in the present work we utilize the parameter sets with more proper symmetric nuclear matter (SNM) predictions for a number of different nucleon radii. To this end, the isoscalar parameters in each parameter set and the cutoff parameter $\beta$ are adjusted by fitting the corresponding SNM properties at sub-saturation density to the prediction of IUFSU parameter set. We have obtained that the assumption of composite nucleons with free space radius $r \le 0.83$ fm is still compatible with the currently acceptable nuclear matter (NM) properties beyond the saturation density. We have also found that the effect of free space nucleon radius could be imprinted in the radius, moment of inertia, and crust properties of the slowly rotating neutron star.