| 1. |
- Aalto, Susanne, 1964, et al.
(författare)
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A precessing molecular jet signaling an obscured, growing supermassive black hole in NGC 1377?
- 2016
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 590, s. Art. no. A73-
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Tidskriftsartikel (refereegranskat)abstract
- With high resolution (0."25 × 0."18) ALMA CO 3-2 (345 GHz) observations of the nearby (D = 21 Mpc, 1" = 102 pc), extremely radio-quiet galaxy NGC 1377, we have discovered a high-velocity, very collimated nuclear outflow which we interpret as a molecular jet with a projected length of ± 150 pc. The launch region is unresolved and lies inside a radius r 40% of the flux in NGC 1377 and may be a slower, wide-angle molecular outflow which is partially entrained by the molecular jet. We discuss the driving mechanism of the molecular jet and suggest that it is either powered by a (faint) radio jet or by an accretion disk-wind similar to those found towards protostars. It seems unlikely that a massive jet could have been driven out by the current level of nuclear activity which should then have undergone rapid quenching. The light jet would only have expelled 10% of the inner gas and may facilitate nuclear activity instead of suppressing it. The nucleus of NGC 1377 harbours intense embedded activity and we detect emission from vibrationally excited HCN J = 4-3?2 = 1f which is consistent with hot gas and dust. We find large columns of H2 in the centre of NGC 1377 which may be a sign of a high rate of recent gas infall. The dynamical age ofthe molecular jet is short (
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| 2. |
- Aalto, Susanne, 1964, et al.
(författare)
-
Luminous, pc-scale CO 6-5 emission in the obscured nucleus of NGC 1377
- 2017
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 608, s. A22-
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Tidskriftsartikel (refereegranskat)abstract
- High-resolution submillimeter line and continuum observations are important in probing the morphology, column density, and dynamics of the molecular gas and dust around obscured active galactic nuclei (AGNs). With high-resolution (0'.06 x 0'.05 (6 x 5 pc)) ALMA 690 GHz observations we have found bright (T-B > 80 K) and compact (full width half maximum size (FWHM) size of 10 x 7 pc) CO 6-5 line emission in the nuclear region of the extremely radio-quiet galaxy NGC 1377. The CO 6-5 intensity is partially aligned with the previously discovered jet/outflow of NGC 1377 and is tracing dense (n > 10(4 )cm(-3)) hot molecular gas at the base of the outflow. The velocity structure is complex and shifts across the jet/outflow are discussed in terms of separate overlapping kinematical components or rotation. High-velocity gas (Delta v +/- 145 km s(-1)) is detected inside r
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