Accretion and outflow activity on the late phases of pre-main-sequence evolution

The case of RZ Piscium

¹ Pulkovo Astronomical Observatory, Russian Academy of Sciences, 196140 Pulkovo, St. Petersburg, Russia
e-mail: ilya.astro@gmail.com
² National Astronomical Research Institute of Thailand, 50200 Chiang Mai, Thailand
³ Saint-Petersburg State University, Universitetski pr. 28, 198504 St. Petersburg, Russia
⁴ Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, 14882 Potsdam, Germany
⁵ Crimean Astrophysical Observatory, 298409 P. Nauchny, Crimea

Received: 13 May 2016
Accepted: 2 December 2016

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 Å and Ca ii IR triplet. We also confirmed the presence of a weak emission component in the Hα line, which allowed us to estimate the mass accretion rate on the star as Ṁ ≤ 7 × 10^-12M_⊙ 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.