# Asteroseismology of the pre-main-sequence $\delta$ Scuti pulsator IP Persei

## TL;DR

This study models the pulsations of the pre-main-sequence star IP Persei, identifying oscillation modes and deriving stellar parameters that suggest it is a young star still undergoing nuclear processes.

## Contribution

The paper presents a detailed asteroseismic analysis of IP Persei, providing new stellar parameters and mode identifications for a pre-main-sequence δ Scuti star.

## Key findings

- Two sets of models fit the observed frequencies well.
- IP Per is a young star with specific mass, age, and chemical composition.
- Identified oscillation modes include one radial, two dipole, and six quadrupole modes.

## Abstract

A grid of theoretical models are computed to fit the 9 oscillation modes of IP Per detected earlier from a multi-site ground-based campaign. Fitting results show that there are two sets of theoretical models that could reproduce the observed frequencies more or less euqally well. In view of other available spectroscopic and photometric measurements, our best fitting stellar parameters for IP Per are $\upsilon_{\rm e} = 91^{+5}_{-3}$ km s$^{-1}$, $Z=0.009^{+0.004}_{-0.001}$, $M = 1.64^{+0.10}_{-0.04}$ $M_{\odot}$, $T_{\rm eff} = 7766^{+348}_{-173}$ K, $\log L/L_{\odot} = 1.125^{+0.094}_{-0.046}$, $\log g = 4.041^{+0.008}_{-0.003}$ dex, $R = 2.022^{+0.042}_{-0.018}$ $R_{\odot}$, $\tau_{0} = 8711^{+68}_{-35}$ s, age = $7.39^{+0.76}_{-0.46}$ Myr. Meanwhile, IP Per is found to be a pre-main sequence star where CN cycle has not yet reached the equilibrium state. At present fourteen percent of C12 have been turned into N14. Based on the best-fitting model, $f_{6}$ is identified as a radial mode, $f_{1}$ and $f_{2}$ as two dipole modes, and $f_{3}$, $f_{4}$, $f_{5}$, $f_{7}$, $f_{8}$, and $f_{9}$ as six quadrupole modes.