Tropospheric Delay Calibrations for VERA
Authors:
Open Access
- 25 October 2008
- journal article
- research article
- Published by Oxford University Press (OUP) in Publications of the Astronomical Society of Japan
- Vol. 60 (5) , 951-960
Abstract
We present techniques for the tropospheric delay calibration, which is the key to increasing the accuracy of the phase-referencing astrometry with Very Long Baseline Interferometry (VLBI). We study three methods, and make a comparison of these methods to discuss the accuracy in calibration. Our results show that all three methods can calibrate the tropospheric zenith delay within accuracy of $\sim$2cm. We also present simulations of positional errors in VLBI Exploration of Radio Astrometry (VERA) at the presence of an error in the tropospheric zenith delay, showing that parallax measurements with accuracy of 10$\mu$as can be readily achieved for sources at high declination and with small separation angles between the target Galactic maser and extragalactic position references.Keywords
This publication has 17 references indexed in Scilit:
- Verification of the Effectiveness of VSOP-2 Phase Referencing with a Newly Developed Simulation Tool, ARISPublications of the Astronomical Society of Japan, 2007
- Water Maser Motions in W3(OH) and a Determination of Its DistanceThe Astrophysical Journal, 2006
- Astrometric accuracy of phase-referenced observations with the VLBA and EVNAstronomy & Astrophysics, 2006
- The Distance to the Perseus Spiral Arm in the Milky WayScience, 2006
- Parallax Measurements of the Mira-Type Star UX Cygni with Phase-referencing VLBIThe Astrophysical Journal, 2005
- The Proper Motion of Sagittarius A*. II. The Mass of Sagittarius A*The Astrophysical Journal, 2004
- A comparison of Global Positioning System retrieved precipitable water vapor with the numerical weather prediction analysis data over the Japanese IslandsJournal of Geophysical Research: Atmospheres, 2000
- Astrometry and geodesy with radio interferometry: experiments, models, resultsReviews of Modern Physics, 1998
- Precise point positioning for the efficient and robust analysis of GPS data from large networksJournal of Geophysical Research, 1997
- Global mapping functions for the atmosphere delay at radio wavelengthsJournal of Geophysical Research, 1996