Astrometry of OH/IR Stars Using 1612MHz Hydroxyl Masers. I. Annual Parallaxes of WX Psc and OH138.0+7.2 MEConference on Why Galaxies Care About AGB Stars III: A Closer Look in Space and Time, JUL 28-AUG
Artikel i vetenskaplig tidskrift, 2017

We report on the measurement of the trigonometric parallaxes of 1612 MHz hydroxyl masers around two asymptotic giant branch stars, WX. Psc and OH. 138.0+7.2, using the NRAO Very Long Baseline Array with in-beam phase referencing calibration. We obtain a 3s upper limit of. <= 5.3 mas on the parallax of WX. Psc, corresponding to a lower limit distance estimate of. 190 pc. The obtained parallax of OH. 138.0+7.2 is 0.52 +/- 0.09 mas (+/- 18%), corresponding to a distance of 1.9(-0.3)(+0.4)kpc, making this the first hydroxyl maser parallax below one milliarcsecond. We also introduce a new method of error analysis for detecting systematic errors in the astrometry. Finally, we compare our trigonometric distances to published phase-lag distances toward these stars and find a good agreement between the two methods.

h2o masers

stars: individual (WX Psc

software

vera

Astronomy & Astrophysics

agb stars

techniques:

stars: AGB and post-AGB

OH 138.0+7.2)

vlbi astrometry

astrometry

pulsars

correlator

distance

proper motions

circumstellar oh masers

masers

Författare

G. Orosz

Kagoshima University

H. Imai

Kagoshima University

R. Dodson

University of Western Australia

M. J. Rioja

Observatorio Astronomico Nacional

CSIRO Astronomy and Space Science

University of Western Australia

S. Frey

Magyar Tudomanyos Akademia

R. A. Burns

Joint Institute for VLBI ERIC

Kagoshima University

S. Etoka

Universität Hamburg

A. Nakagawa

Kagoshima University

H. Nakanishi

SKA Organization

Kagoshima University

JAXA Institute of Space and Astronautical Science

Y. Asaki

National Institutes of Natural Sciences

Atacama Large Millimeter-submillimeter Array (ALMA)

S. R. Goldman

Keele University

Daniel Tafoya Martinez

Chalmers, Rymd- och geovetenskap, Radioastronomi och astrofysik

Chalmers, Rymd- och geovetenskap, Onsala rymdobservatorium

Astronomical Journal

0004-6256 (ISSN) 1538-3881 (eISSN)

Vol. 153 119-

Ämneskategorier

Astronomi, astrofysik och kosmologi

Fundament

Grundläggande vetenskaper

Infrastruktur

Onsala rymdobservatorium

DOI

10.3847/1538-3881/153/3/119