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تسجيل مستخدم جديدFaint Extended OH Emission from the Local Interstellar Medium in the Direction l approx 108circ, b approx 5circ
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We have mapped faint 1667 OH line emission (TA approx 20 - 40 mK in our approx 30 beam) along many lines of sight in the Galaxy covering an area of approx 4circ times 4circ in the general direction of l approx 108circ, b approx 5circ. The OH emission is widespread, similar in extent to the local HI (r </= 2 kpc) both in space and in velocity. The OH profile amplitudes show a good general correlation with those of HI in spectral channels of approx 1 km/s; this relation is described by TA(OH) approx 1.50 times 10^{-4} TB(HI) for values of TB(HI) </approx 60 - 70 K. Beyond this the HI line appears to saturate, and few values are recorded above approx 90 K. However, the OH brightness continues to rise, by a further factor approx 3. The OH velocity profiles show multiple features with widths typically 2 - 3 km/s, but less than 10% of these features are associated with CO(1-0) emission in existing surveys of the area smoothed to comparable resolution.
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