Pulkovo VLBI Analysis Center

PUL VLBI Analysis Center at Pulkovo Observatory

Pulkovo EOP and Reference Systems Analysis Center (PERSAC)

PUL VLBI Analysis Center

General Information
VLBI data analysis
Celestial reference frame
- OCARS
- SREAG
Approaches and occultations
Supporting software
Licensing
Contact

VLBI World

IVS: International VLBI Service for Geodesy and Astrometry
Principles of Radio Interferometry
About VLBI (IVS page)
About VLBI (Wikipedia)

General Information

An IVS VLBI Analysis Center at the Central Astronomical Observatory at Pulkovo of the Russian Academy of Sciences, also widely known as Pulkovo Observatory, has been organized in September 2006. It's IVS acronym is PUL. The center is a part of the Pulkovo EOP and Reference Systems Analysis Center (PERSAC).

The main topics of our activity are:

Improvement of the International Celestial Reference Frame (ICRF).
Analisys of Earth rotation parameters (EOP) series.
Modeling celestial pole offset (CPO) and free core nutation (FCN).

VLBI data analysis

Results of VLBI data analysis can be found at Pulkovo EOP and Reference Systems Analysis Center (PERSAC) page.

ICRF related studies and results

OCARS catalog of optical characteristics of astrometric radio sources:
- References:
  - Malkin Z. A new version of the OCARS catalog of Optical Characteristics of Astrometric Radio Sources. ApJS, 239(2), id. 20 (2018). DOI: 10.3847/1538-4365/aae777
  - Malkin Z. Improving source positions in the OCARS catalog: A first approach.. AJ, 170(1), id. 48 (2025). DOI: 10.3847/1538-3881/addc65
- OCARS catalog files:
  - main catalog file ocars.txt
  - Gaia astrometry for OCARS sources ocars_g.txt
  - photometry data ocars_m.txt
  - cross-identification table ocars_n.txt
  - OCARS catalog in CSV format ocars.csv
Spherical Rectangular Equal-Area Grid (SREAG)
- References:
  - Malkin Z. A new equal-area isolatitudinal grid on a spherical surface. AJ, Vol. 158, No. 4, id. 158, 2019. DOI: 10.3847/1538-3881/ab3a44
  - Malkin Z. Spherical Rectangular Equal-Area Grid (SREAG)-Some features. In: Proc. Journees 2019 Astrometry, Earth Rotation, and Reference Systems in the GAIA era, Paris, France, 7-9 Oct 2019, Ed. Ch. Bizouard, 2020, 55-59. Also available in arXiv:1912.05593
- Supporting routines

Approaches and occultations

Forthcoming mutual events of planets and astrometric radio sources are listed here.

Licensing

All the author's materials and results presented at this webpage are distributed under the terms of the Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution, and reproduction in any medium or format, as long as you give appropriate credit to the original author and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Contact: Zinovy Malkin, e-mail: malkin@gaoran.ru, web: zmalkin.com

Originated on 30 Sep 2006
Last updated on 27 May 2026
Feedback is welcome!