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arXiv · 0809.4672

The Distances of SNRs Kes 69 and G21.5-0.9 from HI and 13CO Spectra

Wenwu Tian·Denis A. Leahy
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Abstract

We obtain new HI and $^{13}$CO images around Supernova Remnants (SNR) Kes 69 and G21.5-0.9. By comparing HI spectra with $^{13}$CO emission spectra, we significantly revise the kinematic distance for Kes 69 to $\sim$ 5.5 kpc, which was 11.2 kpc, and refine the kinematic distance for G21.5-0.9 to ~4.8 kpc. For Kes 69, the highest velocity of absorption is ~86 km/s and a prominent HI emission feature at ~ 112 km/s has no respective absorption. These new results suggest that Kes 69 is associated with a newly detected extended 1720 MHz OH maser at velocity of ~85 km/s that originates from within the bright southern radio shell of Kes 69. For G21.5-0.9, the highest velocity of absorption is ~67 km/s. The HI absorption spectra of the nearby bright source PMN J1832-1035 and of Kes 69 show a common absorption feature at velocity of ~69 km/s, which is not seen for G21.5-0.9. The resulting velocity of ~68 km/s gives the best distance estimate of ~4.8 kpc for G21.5-0.9 and associated young pulsar J1833-1034.

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Wenwu Tian, Denis A. Leahy. 2008-09-26. The Distances of SNRs Kes 69 and G21.5-0.9 from HI and 13CO Spectra. https://doi.org/10.1111/j.1745-3933.2008.00557.x

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