We have performed a high sensitivity observation of the UFO/BAL quasar APM 08279+5255 at z=3.912 with NOEMA at 3.2 mm, aimed at detecting fast moving molecular gas. We report the detection of blueshifted CO(4-3) with maximum velocity (v95%) of $-1340$ km s$^-1$, with respect to the systemic peak emission, and a luminosity of $L' = 9.9 imes 10^9 ~mu^-1$ K km s$^-1$ pc$^-2$ (where $mu$ is the lensing magnification factor). We discuss various scenarios for the nature of this emission, and conclude that this is the first detection of fast molecular gas at redshift $>3$. We derive a mass flow rate of molecular gas in the range $ m dot M=3-7.4 imes 10^3$ M$_odot$/yr, and momentum boost $dot P_OF / dot P_AGN sim 2-6$, therefore consistent with a momentum conserving flow. For the largest $dot P_OF$ the scaling is also consistent with a energy conserving flow with an efficiency of $sim$10-20%. The present data can hardly discriminate between the two expansion modes. The mass loading factor of the molecular outflow $eta=dot M_OF/SFR$ is $>>1$. We also detect a molecular emission line at a frequency of 94.83 GHz, corresponding to a rest frame frequency of 465.8 GHz, which we tentatively identified with the cation molecule $ m N_2H^+$(5-4), which would be the first detection of this species at high redshift. We discuss the alternative possibility that this emission is due to a CO emission line from the, so far undetected, lens galaxy. Further observations of additional transitions of the same species with NOEMA can discriminate between the two scenarios.
We have performed a high sensitivity observation of the UFO/BAL quasar APM 08279+5255 at z=3.912 with NOEMA at 3.2 mm, aimed at detecting fast moving molecular gas. We report the detection of blueshifted CO(4-3) with maximum velocity (v95%) of $-1340$ km s$^{-1}$, with respect to the systemic peak emission, and a luminosity of $L' = 9.9 imes 10^9 ~mu^{-1}$ K km s$^{-1}$ pc$^{-2}$ (where $mu$ is the lensing magnification factor). We discuss various scenarios for the nature of this emission, and conclude that this is the first detection of fast molecular gas at redshift $>3$. We derive a mass flow rate of molecular gas in the range $ m dot M=3-7.4 imes 10^3$ M$_odot$/yr, and momentum boost $dot P_{OF} / dot P_{AGN} sim 2-6$, therefore consistent with a momentum conserving flow. For the largest $dot P_{OF}$ the scaling is also consistent with a energy conserving flow with an efficiency of $sim$10-20%. The present data can hardly discriminate between the two expansion modes. The mass loading factor of the molecular outflow $eta=dot M_{OF}/SFR$ is $>>1$. We also detect a molecular emission line at a frequency of 94.83 GHz, corresponding to a rest frame frequency of 465.8 GHz, which we tentatively identified with the cation molecule $ m N_2H^+$(5-4), which would be the first detection of this species at high redshift. We discuss the alternative possibility that this emission is due to a CO emission line from the, so far undetected, lens galaxy. Further observations of additional transitions of the same species with NOEMA can discriminate between the two scenarios.
On the discovery of fast molecular gas in the UFO/BAL quasar APM 08279+5255 at z=3.912
C. Feruglio;A. Ferrara;C. Ceccarelli;C. Cicone;S. Gallerani;R. Maiolino;E. Piconcelli;
2017
Abstract
We have performed a high sensitivity observation of the UFO/BAL quasar APM 08279+5255 at z=3.912 with NOEMA at 3.2 mm, aimed at detecting fast moving molecular gas. We report the detection of blueshifted CO(4-3) with maximum velocity (v95%) of $-1340$ km s$^{-1}$, with respect to the systemic peak emission, and a luminosity of $L' = 9.9 imes 10^9 ~mu^{-1}$ K km s$^{-1}$ pc$^{-2}$ (where $mu$ is the lensing magnification factor). We discuss various scenarios for the nature of this emission, and conclude that this is the first detection of fast molecular gas at redshift $>3$. We derive a mass flow rate of molecular gas in the range $ m dot M=3-7.4 imes 10^3$ M$_odot$/yr, and momentum boost $dot P_{OF} / dot P_{AGN} sim 2-6$, therefore consistent with a momentum conserving flow. For the largest $dot P_{OF}$ the scaling is also consistent with a energy conserving flow with an efficiency of $sim$10-20%. The present data can hardly discriminate between the two expansion modes. The mass loading factor of the molecular outflow $eta=dot M_{OF}/SFR$ is $>>1$. We also detect a molecular emission line at a frequency of 94.83 GHz, corresponding to a rest frame frequency of 465.8 GHz, which we tentatively identified with the cation molecule $ m N_2H^+$(5-4), which would be the first detection of this species at high redshift. We discuss the alternative possibility that this emission is due to a CO emission line from the, so far undetected, lens galaxy. Further observations of additional transitions of the same species with NOEMA can discriminate between the two scenarios.File | Dimensione | Formato | |
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