# Effect of superfluid matter of neutron star on the tidal deformability

## TL;DR

This paper investigates how superfluidity in the neutron star core influences its tidal deformability, highlighting the importance of multiple tidal parameters for gravitational wave analysis.

## Contribution

It introduces a dual-layer model with superfluid core and ordinary matter envelope to analyze tidal responses in neutron stars.

## Key findings

- Superfluidity affects tidal Love numbers significantly.
- Entrainment between fluids alters the tidal response.
- Multiple tidal parameters are needed to probe superfluidity.

## Abstract

We study the effect of superfluidity on the tidal response of a neutron star in a general relativistic framework. In this work, we take a dual-layer approach where the superfluid matter is confined in the core of the star. Then, the superfluid core is encapsulated with an envelope of ordinary matter fluid which acts effectively as the low-density crustal region of the star. In the core, the matter content is described by a two-fluid model where only the neutrons are taken as superfluid and the other fluid consists of protons and electrons making it charge neutral. We calculate the values of various tidal love numbers of a neutron star and discuss how they are affected due to the presence of entrainment between the two fluids in the core. We also emphasize that more than one tidal parameter is necessary to probe superfluidity with the gravitational wave from the binary inspiral.