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High Resolution X-ray Spectroscopy of Pre-Main-Sequence Stars TWA 5 and PZ Tel
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HIGH RESOLUTION X-RAY SPECTROSCOPY OF PRE-MAIN-SEQUENCE STARS: TWA 5
AND PZ TEL
C. Argiroffi1, J. J. Drake2, F. R. Harnden2, A. Maggio3, G. Peres1, S. Sciortino3, B. Stelzer3, and
R. Neuha?user4
1Dipartimento di Scienze Fisiche ed Astronomiche, Sezione di Astronomia, Universita? di Palermo, Piazza del Parlamento 1,
90134 Palermo, Italy
2Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138
3INAF - Osservatorio Astronomico di Palermo, Piazza del Parlamento 1, 90134 Palermo, Italy
4Astrophysikalisches Institut und Universita?ts-Sternwarte, Schillerga?sschen 2-3, D-07745 Jena, Germany
Abstract
We report on the analysis of high resolution X-ray
spectra of two pre-main-sequence stars: TWA 5 (observed
with XMM-Newton) and PZ Telescopii (observed with
Chandra/HETGS). TWA 5 is a classical T Tauri star in
the TW Hydrae association while PZ Tel is a rapidly ro-
tating weak-lined T Tauri star in the β-Pictoris moving
group. For both stars we have reconstructed the emis-
sion measure distribution and derived the coronal abun-
dances to check for possible patterns of the abundances
related to the first ionization potential of the various ele-
ments. We have also derived estimates of the plasma den-
sity from the analysis of the He-like triplets. We compare
the characteristics of our targets with those of other pre-
main sequence stars previously analyzed by other authors:
TW Hya, HD 98800 and HD 283572. Our findings suggest
that X-ray emission from classical T Tauri and weak-lined
T Tauri stars is produced in all cases by magnetically-
heated coronae, except for TW Hya which has unique
plasma temperatures and densities. Moreover we derive
that TWA 5 has the same peculiar Ne/Fe abundance ra-
tio as TW Hya.
Key words: Stars: pre-main-sequence – Techniques: spec-
troscopic – X-rays: stars
1. Introduction
The aim of the present work is to investigate the evolution
of stellar X-ray emissio
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