TY - JOUR
T1 - The position of Sagittarius A* at the galactic center
AU - Yusef-Zadeh, F.
AU - Choate, D.
AU - Cotton, W.
N1 - Funding Information:
1The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under a cooperative agreement by Associated Universities, Inc.
PY - 1999/6/10
Y1 - 1999/6/10
N2 - The absolute position of the compact radio source at the dynamical center of the Galaxy, Sagittarius A*, was known only to an accuracy of 0″.2 in spite of its accurate location with respect to near-IR stellar sources to within 30 mas. To remedy this poor positional accuracy, we have selected 15 high-resolution, high-frequency VLA observations of Sgr A* carried out in the last 13 years and determined the weighted average position with the average epoch 1992.4 to be at α, δ (1950) = 17h42m29s.3076 ± 0s.0007, -28°59′18″.484 ± 0″.014 or α, δ (2000) = 17h45m40s.0383 ± 0s.0007, -29°00′28″.069 ± 0″.014, which agrees with earlier published values to within the 0″.2 error bars of the earlier measurements. An accurate absolute position of Sgr A* can be useful for its identification with sources at other wavelengths, particularly in soft and hard X-rays, with implications for the models of a massive black hole at the Galactic center.
AB - The absolute position of the compact radio source at the dynamical center of the Galaxy, Sagittarius A*, was known only to an accuracy of 0″.2 in spite of its accurate location with respect to near-IR stellar sources to within 30 mas. To remedy this poor positional accuracy, we have selected 15 high-resolution, high-frequency VLA observations of Sgr A* carried out in the last 13 years and determined the weighted average position with the average epoch 1992.4 to be at α, δ (1950) = 17h42m29s.3076 ± 0s.0007, -28°59′18″.484 ± 0″.014 or α, δ (2000) = 17h45m40s.0383 ± 0s.0007, -29°00′28″.069 ± 0″.014, which agrees with earlier published values to within the 0″.2 error bars of the earlier measurements. An accurate absolute position of Sgr A* can be useful for its identification with sources at other wavelengths, particularly in soft and hard X-rays, with implications for the models of a massive black hole at the Galactic center.
KW - Galaxies: ISM
KW - Galaxy: center
KW - ISM: individual (Sagittarius A)
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U2 - 10.1086/312058
DO - 10.1086/312058
M3 - Article
AN - SCOPUS:0040532115
SN - 0004-637X
VL - 518
SP - L33-L35
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1 PART 2
ER -