2000A&A...360..161P


Query : 2000A&A...360..161P

2000A&A...360..161P - Astronomy and Astrophysics, volume 360, 161-170 (2000/8-1)

Towards global phase-delay VLBI astrometry: observations of QSO 1150+812 and BL 1803+784.

PEREZ-TORRES M.A., MARCAIDE J.M., GUIRADO J.C., ROS E., SHAPIRO I.I., RATNER M.I. and SARDON E.

Abstract (from CDS):

On 18 November 1993, we observed the QSO 1150+812 and the BL Lac object 1803+784, nearly 15° apart on the sky, with a VLBI array, simultaneously recording at 8.4 and 2.3GHz. Using difference astrometry techniques, we determined the coordinates of 1803+784 relative to those of 1150+812 to be Δα=6h7m33.18469s±0.00020s Δδ=-2°30'25.13557"±0.00075." These standard errors contain estimated contributions from the propagation medium, the effects of source opacity, and the possible misidentification of the reference point in some of the maps. We obtained comparably accurate and consistent relative positions of the radio sources with GPS-based ionosphere corrections, thus demonstrating that dual-frequency observations are not required for state-of-the-art accuracy in VLBI astrometry. These results also demonstrate the feasibility of using single-frequency measurements for sources separated by 15° on the sky, and open the avenue for the application of this technique on a full-sky scale.

Abstract Copyright:

Journal keyword(s): astrometry - techniques: interferometric - galaxies: quasars: individual: QSO 1150+812 - galaxies: BL Lacertae objects: individual: BL 1803+784

Nomenclature: Fig.1: [PMG2000] 1803+784 XN (Nos X1-X3), [PMG2000] 1803+784 SN (Nos S1-S3). Fig.2: [PMG2000] 1150+812 XN (Nos X1-X4), [PMG2000] 1150+812 SN (Nos S1-S4).

Simbad objects: 5

goto View the references in ADS

Number of rows : 5
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2024
#notes
1 ICRF J104146.7+523328 Sy1 10 41 46.78165398 +52 33 28.2317956   16.96 18.5 16.39   ~ 135 1
2 8C 1150+812 QSO 11 53 12.49922322 +80 58 29.1545718     19.40 18.54   ~ 237 1
3 3C 273 BLL 12 29 06.6998257176 +02 03 08.597629980   13.05 14.830 14.11   ~ 5802 1
4 8C 1803+784 BLL 18 00 45.6838528560 +78 28 04.018028016   16.4 15.90 15.46   ~ 741 1
5 ICRF J190255.9+315941 Sy1 19 02 55.93889653 +31 59 41.7016439     17.5     ~ 271 2

To bookmark this query, right click on this link: simbad:objects in 2000A&A...360..161P and select 'bookmark this link' or equivalent in the popup menu