# Accretion and outflow activity on the late phases of pre-main-sequence evolution. The case of RZ Piscium

## TL;DR

This study investigates the accretion and outflow activities of the pre-main-sequence star RZ Psc through spectroscopic observations, revealing variable wind signatures, weak accretion indicators, and potential periodicity in absorption features.

## Contribution

It provides new spectroscopic data on RZ Psc, identifying variable wind signatures and estimating a very low mass accretion rate, contributing to understanding late-stage pre-main-sequence evolution.

## Key findings

- Variable blueshifted absorption components in alkali metal lines.
- Weak Hα emission indicating low accretion rate.
- Possible periodicity in sodium line absorption features.

## Abstract

RZ Psc is an isolated high-latitude post-T Tauri star that demonstrates a UX Ori-type photometric activity. The star shows very weak spectroscopic signatures of accretion, but at the same time possesses the unusual footprints of the wind in Na I D lines. In the present work we investigate new spectroscopic observations of RZ Psc obtained in 2014 during two observation runs. We found variable blueshifted absorption components (BACs) in lines of the other alcali metals, K I 7699 \AA\ and Ca II IR triplet. We also confirmed the presence of a weak emission component in the H$\alpha$ line, which allowed us to estimate the mass accretion rate on the star as $\dot{M}\leq$ $7 \cdot 10^{-12}$Msun yr$^{-1}$. We could not reveal any clear periodicity in the appearance of BACs in sodium lines. Nevertheless, the exact coincidence of the structure and velocities of the Na I D absorptions observed with the interval of about one year suggests that such a periodicity should exist.