Rigorous treatment of barycentric stellar motion Perspective and light-time effects in astrometric and radial velocity data
Butkevich, A. G. and Lindegren, Lennart LU
(2014)
In Astronomy & Astrophysics
570.
- Abstract
- Context. High-precision astrometric and radial-velocity observations require accurate modelling of stellar motions in order to extrapolate measurements over long time intervals, and to detect deviations from uniform motion caused, for example, by unseen companions. Aims. We aim to explore the simplest possible kinematic model of stellar motions, namely that of uniform rectilinear motion relative to the solar system barycentre, in terms of observable quantities including error propagation. Methods. The apparent path equation for uniform rectilinear motion is solved analytically in a classical (special-relativistic) framework, leading to rigorous expressions that relate the (apparent) astrometric parameters and radial velocity to the (true)... (More)
- Context. High-precision astrometric and radial-velocity observations require accurate modelling of stellar motions in order to extrapolate measurements over long time intervals, and to detect deviations from uniform motion caused, for example, by unseen companions. Aims. We aim to explore the simplest possible kinematic model of stellar motions, namely that of uniform rectilinear motion relative to the solar system barycentre, in terms of observable quantities including error propagation. Methods. The apparent path equation for uniform rectilinear motion is solved analytically in a classical (special-relativistic) framework, leading to rigorous expressions that relate the (apparent) astrometric parameters and radial velocity to the (true) kinematic parameters of the star in the barycentric reference system. Results. We present rigorous and explicit formulae for the transformation of stellar positions, parallaxes, proper motions, and radial velocities from one epoch to another, assuming uniform rectilinear motion and taking light-time effects into account. The Jacobian matrix of the transformation is also given, allowing accurate and reversible propagation of errors over arbitrary time intervals. The light-time effects are generally very small, but exceed 0.1 mas or 0.1 m s(-1) over 100 yr for at least 33 stars in the Hipparcos catalogue. For high-velocity stars within a few tens of pc from the Sun, light-time effects are generally more important than the effects of the curvature of their orbits in the Galactic potential. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/4875696
- author
- Butkevich, A. G.
and Lindegren, Lennart
LU
- organization
- publishing date
- 2014
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- methods: data analysis, technique: radial velocity, astrometry, parallaxes, proper motions, reference systems
- in
- Astronomy & Astrophysics
- volume
- 570
- article number
- A62
- publisher
- EDP Sciences
- external identifiers
-
- wos:000344158500120
- scopus:84907966246
- ISSN
- 0004-6361
- DOI
- 10.1051/0004-6361/201424483
- language
- English
- LU publication?
- yes
- id
- 432486a7-d607-4b06-a1dc-028bc1d46716 (old id 4875696)
- date added to LUP
- 2016-04-01 13:38:59
- date last changed
- 2024-01-09 16:29:53
@article{432486a7-d607-4b06-a1dc-028bc1d46716,
abstract = {{Context. High-precision astrometric and radial-velocity observations require accurate modelling of stellar motions in order to extrapolate measurements over long time intervals, and to detect deviations from uniform motion caused, for example, by unseen companions. Aims. We aim to explore the simplest possible kinematic model of stellar motions, namely that of uniform rectilinear motion relative to the solar system barycentre, in terms of observable quantities including error propagation. Methods. The apparent path equation for uniform rectilinear motion is solved analytically in a classical (special-relativistic) framework, leading to rigorous expressions that relate the (apparent) astrometric parameters and radial velocity to the (true) kinematic parameters of the star in the barycentric reference system. Results. We present rigorous and explicit formulae for the transformation of stellar positions, parallaxes, proper motions, and radial velocities from one epoch to another, assuming uniform rectilinear motion and taking light-time effects into account. The Jacobian matrix of the transformation is also given, allowing accurate and reversible propagation of errors over arbitrary time intervals. The light-time effects are generally very small, but exceed 0.1 mas or 0.1 m s(-1) over 100 yr for at least 33 stars in the Hipparcos catalogue. For high-velocity stars within a few tens of pc from the Sun, light-time effects are generally more important than the effects of the curvature of their orbits in the Galactic potential.}},
author = {{Butkevich, A. G. and Lindegren, Lennart}},
issn = {{0004-6361}},
keywords = {{methods: data analysis; technique: radial velocity; astrometry; parallaxes; proper motions; reference systems}},
language = {{eng}},
publisher = {{EDP Sciences}},
series = {{Astronomy & Astrophysics}},
title = {{Rigorous treatment of barycentric stellar motion Perspective and light-time effects in astrometric and radial velocity data}},
url = {{http://dx.doi.org/10.1051/0004-6361/201424483}},
doi = {{10.1051/0004-6361/201424483}},
volume = {{570}},
year = {{2014}},
}