اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدOutflowing atomic and molecular gas at $z sim 0.67$ towards 1504+377
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Nissim Kanekar
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We report the detection of OH 1667 MHz and wide HI 21cm absorption at $z sim 0.67$ towards the red quasar 1504+377, with the Green Bank Telescope and the Giant Metrewave Radio Telescope. The HI 21cm absorption extends over a velocity range of $sim 600$ km/s blueward of the quasar redshift ($z=0.674$), with the new OH 1667 MHz absorption component at $sim -430$ kms, nearly coincident with earlier detections of mm-wave absorption at $z sim 0.6715$. The atomic and molecular absorption appear to arise from a fast gas outflow from the quasar, with a mass outflow rate ${dot M} sim 12 M_odot$ yr$^{-1}$ and a molecular hydrogen fraction $f_{rm H_2} equiv (N_{rm H_2}/N_{rm HI}) sim 0.2$. The radio structure of 1504+377 is consistent with the outflow arising due to a jet-cloud interaction, followed by rapid cooling of the cloud material. The observed ratio of HCO$^+$ to OH column densities is $sim 20$ times higher than typical values in Galactic and high-$z$ absorbers. This could arise due to small-scale structure in the outflowing gas on sub-parsec scales, which would also explain the observed variability in the HI 21cm line.
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