Massive Molecular Outflow and 100 kpc Extended Cold Halo Gas in the Enormous Lyα Nebula of QSO 1228+3128

Abstract The link between the circumgalactic medium (CGM) and the stellar growth of massive galaxies at high-z depends on the properties of the widespread cold molecular gas. As part of the SUPERCOLD-CGM survey (Survey of Protocluster ELANe Revealing CO/[C i] in the Lyα-Detected CGM), we present the radio-loud QSO Q1228+3128 at z = 2.2218, which is embedded in an enormous Lyα nebula. ALMA+ACA observations of CO(4–3) reveal both a massive molecular outflow, and a more extended molecular gas reservoir across ∼100 kpc in the CGM, each containing a mass of M H2 ∼ 4–5 × 1010 M ⊙. The outflow and molecular CGM are aligned spatially, along the direction of an inner radio jet. After reanalysis of Lyα data of Q1228+3128 from the Keck Cosmic Web Imager, we found that the velocity of the extended CO agrees with the redshift derived from the Lyα nebula and the bulk velocity of the massive outflow. We propose a scenario where the radio source in Q1228+3128 is driving the molecular outflow and perhaps also enriching or cooling the CGM. In addition, we found that the extended CO emission is nearly perpendicular to the extended Lyα nebula spatially, indicating that the two gas phases are not well mixed, and possibly even represent different phenomena (e.g., outflow versus infall). Our results provide crucial evidence in support of predicted baryonic recycling processes that drive the early evolution of massive galaxies.

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Molecular outflow and feedback in the obscured quasar XID2028 revealed by ALMA

Astronomy and Astrophysics ◽

10.1051/0004-6361/201731641 ◽

2018 ◽

Vol 612 ◽

pp. A29 ◽

Cited By ~ 30

Author(s):

M. Brusa ◽

G. Cresci ◽

E. Daddi ◽

R. Paladino ◽

M. Perna ◽

...

Keyword(s):

Host Galaxy ◽

Molecular Gas ◽

Test Case ◽

Feedback Effects ◽

Molecular Outflow ◽

The Galaxy ◽

Gas Consumption ◽

Massive Outflow ◽

Gas Component ◽

Fast Rotating

We imaged, with ALMA and ARGOS/LUCI, the molecular gas and dust and stellar continuum in XID2028, which is an obscured quasi-stellar object (QSO) at z = 1.593, where the presence of a massive outflow in the ionised gas component traced by the [OIII]5007 emission has been resolved up to 10 kpc. This target represents a unique test case to study QSO feedback in action at the peak epoch of AGN-galaxy co-evolution. The QSO was detected in the CO(5 − 4) transition and in the 1.3 mm continuum at ~30 and ~20σ significance, respectively; both emissions are confined in the central (<2 kpc) radius area. Our analysis suggests the presence of a fast rotating molecular disc (v ~ 400 km s−1) on very compact scales well inside the galaxy extent seen in the rest-frame optical light (~10 kpc, as inferred from the LUCI data). Adding available measurements in additional two CO transitions, CO(2 − 1) and CO(3 − 2), we could derive a total gas mass of ~1010 M⊙, thanks to a critical assessment of CO excitation and the comparison with the Rayleigh–Jeans continuum estimate. This translates into a very low gas fraction (<5%) and depletion timescales of 40–75 Myr, reinforcing the result of atypical gas consumption conditions in XID2028, possibly because of feedback effects on the host galaxy. Finally, we also detect the presence of high velocity CO gas at ~5σ, which we interpret as a signature of galaxy-scale molecular outflow that is spatially coincident with the ionised gas outflow. XID2028 therefore represents a unique case in which the measurement of total outflowing mass, of ~500–800 M⊙ yr−1 including the molecular and atomic components in both the ionised and neutral phases, was attempted for a high-z QSO.

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Evidence of galaxy interaction in the narrow-line Seyfert 1 galaxy IRAS 17020+4544 seen by NOEMA

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3626 ◽

2020 ◽

Vol 501 (1) ◽

pp. 219-228

Author(s):

Q Salomé ◽

A L Longinotti ◽

Y Krongold ◽

C Feruglio ◽

V Chavushyan ◽

...

Keyword(s):

Gas Content ◽

Host Galaxy ◽

Molecular Gas ◽

Narrow Line ◽

Nuclear Region ◽

X Ray ◽

Molecular Outflow ◽

Galaxy Interaction ◽

Massive Outflow ◽

First Time

ABSTRACT The narrow-line Seyfert 1 galaxy IRAS 17020+4544 is one of the few sources where both an X-ray ultrafast outflow and a molecular outflow were observed to be consistent with energy conservation. However, IRAS 17020+4544 is less massive and has a much more modest active galactic nucleus (AGN) luminosity than the other examples. Using recent CO(1–0) observations with the NOrthern Extended Millimeter Array, we characterized the molecular gas content of the host galaxy for the first time. We found that the molecular gas is distributed into an apparent central disc of 1.1 × 109 M⊙, and a northern extension located up to 8 kpc from the centre with a molecular gas mass $M_{\mathrm{ H}_2}\sim 10^8\, \mathrm{ M}_\odot$. The molecular gas mass and the CO dynamics in the northern extension reveal that IRAS 17020+4544 is not a standard spiral galaxy, instead it is interacting with a dwarf object corresponding to the northern extension. This interaction possibly triggers the high accretion rate on to the supermassive black hole. Within the main galaxy, which hosts the AGN, a simple analytical model predicts that the molecular gas may lie in a ring, with less molecular gas in the nuclear region. Such distribution may be the result of the AGN activity that removes or photodissociates the molecular gas in the nuclear region (AGN feedback). Finally, we have detected a molecular outflow of mass $M_{\mathrm{ H}_2}=(0.7\!-\!1.2)\times 10^7\, \mathrm{ M}_\odot$ in projection at the location of the northern galaxy, with a similar velocity to that of the massive outflow reported in previous millimetre data obtained by the Large Millimeter Telescope.

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Tracing the cold molecular gas reservoir through dust emission in the SMC

Proceedings of the International Astronomical Union ◽

10.1017/s174392130802838x ◽

2008 ◽

Vol 4 (S256) ◽

pp. 148-153

Author(s):

Caroline Bot ◽

Mónica Rubio ◽

François Boulanger ◽

Marcus Albrecht ◽

Frank Bertoldi ◽

...

Keyword(s):

Molecular Clouds ◽

Virial Theorem ◽

Spectral Energy Distribution ◽

Dust Emission ◽

Spectral Energy ◽

Molecular Gas ◽

Giant Molecular Clouds ◽

Gas Reservoir ◽

Co Emission ◽

Co Observations

AbstractThe amount of molecular gas is a key for understanding the future star formation in a galaxy. However, this quantity is difficult to infer as the cold H2 is almost impossible to observe and, especially at low metallicities, CO only traces part of the clouds, keeping large envelopes of H2 hidden from observations. In this context, millimeter dust emission tracing the cold and dense regions can be used as a tracer to unveil the total molecular gas masses. I present studies of a sample of giant molecular clouds in the Small Magellanic Cloud. These clouds have been observed in the millimeter and sub-millimeter continuum of dust emission: with SIMBA/SEST at 1.2 mm and the new LABOCA bolometer on APEX at 870 μm. Combining these with radio data for each cloud, the spectral energy distribution of dust emission are obtained and gas masses are inferred. The molecular cloud masses are found to be systematically larger than the virial masses deduced from CO emission. Therefore, the molecular gas mass in the SMC has been underestimated by CO observations, even through the dynamical masses. This result confirms what was previously observed by Bot et al. (2007). We discuss possible interpretations of the mass discrepancy observed: in the giant molecular clouds of the SMC, part of cloud's support against gravity could be given by a magnetic field. Alternatively, the inclusion of surface terms in the virial theorem for turbulent clouds could reproduce the observed results and the giant molecular clouds could be transient structures.

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Discovery of a Highly Collimated Flow from the High-mass Protostar ISOSS J23053+5953 SMM2

The Astrophysical Journal ◽

10.3847/1538-4357/ac2366 ◽

2021 ◽

Vol 922 (1) ◽

pp. 66

Author(s):

Tatiana M. Rodríguez ◽

Peter Hofner ◽

Esteban D. Araya ◽

Qizhou Zhang ◽

Hendrik Linz ◽

...

Keyword(s):

Dust Emission ◽

High Mass ◽

Continuum Emission ◽

Large Array ◽

Lower Velocity ◽

Very Large Array ◽

Molecular Outflow ◽

Systemic Velocity ◽

Massive Outflow ◽

Co Emission

Abstract We present Very Large Array C-, X-, and Q-band continuum observations, as well as 1.3 mm continuum and CO(2-1) observations with the Submillimeter Array toward the high-mass protostellar candidate ISOSS J23053+5953 SMM2. Compact centimeter continuum emission was detected near the center of the SMM2 core with a spectral index of 0.24(± 0.15) between 6 and 3.6 cm, and a radio luminosity of 1.3(±0.4) mJy kpc2. The 1.3 mm thermal dust emission indicates a mass of the SMM2 core of 45.8 (±13.4) M ⊙, and a density of 7.1 (±1.2)× 106 cm−3. The CO(2-1) observations reveal a large, massive molecular outflow centered on the SMM2 core. This fast outflow (>50 km s−1 from the cloud systemic velocity) is highly collimated, with a broader, lower-velocity component. The large values for outflow mass (45.2 ± 12.6 M ⊙) and momentum rate (6 ± 2 × 10−3 M ⊙ km s−1yr−1) derived from the CO emission are consistent with those of flows driven by high-mass YSOs. The dynamical timescale of the flow is between 1.5 and 7.2 × 104 yr. We also found from the C18O to thermal dust emission ratio that CO is depleted by a factor of about 20, possibly due to freeze-out of CO molecules on dust grains. Our data are consistent with previous findings that ISOSS J23053 + 5953 SMM2 is an emerging high-mass protostar in an early phase of evolution, with an ionized jet and a fast, highly collimated, and massive outflow.

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ALMA observations of PKS 1549–79: a case of feeding and feedback in a young radio quasar

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936248 ◽

2019 ◽

Vol 632 ◽

pp. A66 ◽

Cited By ~ 3

Author(s):

Tom Oosterloo ◽

Raffaella Morganti ◽

Clive Tadhunter ◽

J. B. Raymond Oonk ◽

Hayley E. Bignall ◽

...

Keyword(s):

Molecular Gas ◽

Massive Black Hole ◽

Bolometric Luminosity ◽

Molecular Outflow ◽

Long Baseline ◽

The Galaxy ◽

Outflow Rate ◽

Mass Outflow ◽

Gas Accretion ◽

Massive Outflow

We present CO(1−0) and CO(3−2) Atacama Large Millimeter/submillimeter Array observations of the molecular gas in PKS 1549−79, as well as mm and very long baseline interferometry 2.3-GHz continuum observations of its radio jet. PKS 1549−79 is one of the closest young, radio-loud quasars caught in an on-going merger in which the active galactic nucleus (AGN) is in the first phases of its evolution. We detect three structures tracing the accretion and the outflow of molecular gas: kpc-scale tails of gas accreting onto PKS 1549−79 from a merger, a circumnuclear disc in the inner few hundred parsec, and a very broad (> 2300 km s−1) component detected in CO(1−0) at the position of the AGN. Thus, in PKS 1549−79 we see the co-existence of accretion and the ejection of gas. The line ratio CO(3−2)/CO(1−0) suggests that the gas in the circumnuclear-disc has both high densities and high kinetic temperatures. We estimate a mass outflow rate of at least 650 M⊙ yr−1. This massive outflow is confined to the inner region (r < 120 pc) of the galaxy, which suggests that the AGN drives the outflow. Considering the amount of molecular gas available in the central nuclear disc and the observed outflow rate, we estimate a time scale of ∼105 yr over which the AGN would be able to destroy the circumnuclear disc, although gas from the merger may come in from larger radii, rebuilding this disc at the same time. The AGN appears to self-regulate gas accretion to the centre and onto the super-massive black hole. Surprisingly, from a comparison with Hubble Space Telescope data, we find that the ionised gas outflow is more extended. Nevertheless, the warm outflow is about two orders of magnitude less massive than the molecular outflow. PKS 1549−79 does not seem to follow the scaling relation between bolometric luminosity and the relative importance of warm ionised and molecular outflows claimed to exist for other AGN. We argue that, although PKS 1549−79 hosts a powerful quasar nucleus and an ultra-fast outflow, the radio jet plays a significant role in producing the outflow, which creates a cocoon of disturbed gas that expands into the circumnuclear disc.

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More than star formation: High-J CO SLEDs of high-z galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921319008895 ◽

2019 ◽

Vol 15 (S352) ◽

pp. 162-167

Author(s):

Chelsea E. Sharon ◽

Reni Chng ◽

Kebron K. Gurara ◽

Axel Weiß ◽

Jeremy Darling ◽

...

Keyword(s):

Star Formation ◽

Theoretical Work ◽

Molecular Gas ◽

Gas Reservoirs ◽

Local Universe ◽

Line Energy ◽

Massive Galaxies ◽

Molecular Outflows ◽

Very High ◽

Co Emission

AbstractTheoretical work suggests that AGNs play an important role in quenching star formation in massive galaxies. In addition to molecular outflows observed in the local universe, emission from very high-J CO rotational transitions have been a key piece of evidence for AGN directly affecting the molecular gas reservoirs that fuel star formation. However, very few observations exist of CO rotational lines past the peak of the CO spectral line energy distribution (SLED) for galaxies in the early universe. Here we present new ALMA observations of high-J CO rotational lines (from CO(5–4) to CO(16–15)) in six z > 2 IR-bright systems, including several sources not known to contain a strong AGN for comparison. We detect significant amounts of high-excitation CO emission that suggests the presence of energy sources beyond UV-heating.

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ALMA detects molecular gas in the halo of the powerful radio galaxy TXS 0828+193

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3998 ◽

2020 ◽

Author(s):

Judit Fogasy ◽

K K Knudsen ◽

G Drouart ◽

B Gullberg

Keyword(s):

Large Scale ◽

High Redshift ◽

Molecular Gas ◽

Filamentary Structure ◽

Massive Galaxies ◽

Star Forming ◽

Normal Star ◽

The Universe ◽

Co Emission ◽

Powerful Radio Galaxy

Abstract Both theoretical and observational results suggest that high-redshift radio galaxies (HzRGs) inhabit overdense regions of the universe and might be the progenitors of local, massive galaxies residing in the centre of galaxy clusters. In this paper we present CO(3–2) line observations of the HzRG TXS 0828+193 (z = 2.57) and its environment using the Atacama Large Millimeter/submillimeter Array. In contrast to previous observations, we detect CO emission associated with the HzRG and derive a molecular gas mass of $(0.9\pm 0.3)\times 10^{10}\, \rm M_{\odot }$. Moreover, we confirm the presence of a previously detected off-source CO emitting region (companion #1), and detect three new potential companions. The molecular gas mass of each companion is comparable to that of the HzRG. Companion #1 is aligned with the axis of the radio jet and has stellar emission detected by Spitzer. Thus this source might be a normal star-forming galaxy or alternatively a result of jet-induced star formation. The newly found CO sources do not have counterparts in any other observing band and could be high-density clouds in the halo of TXS 0828+193 and thus potentially linked to the large-scale filamentary structure of the cosmic web.

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Cold gas studies of a z = 2.5 protocluster

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320004226 ◽

2020 ◽

Vol 15 (S359) ◽

pp. 136-140

Author(s):

Minju M. Lee ◽

Ichi Tanaka ◽

Rohei Kawabe

Keyword(s):

Galaxy Evolution ◽

High Redshift ◽

Kinematic Model ◽

Molecular Gas ◽

General View ◽

Massive Galaxies ◽

Star Forming ◽

Gas Kinematics ◽

Narrow Band Filter ◽

Stellar Masses

AbstractWe present studies of a protocluster at z =2.5, an overdense region found close to a radio galaxy, 4C 23.56, using ALMA. We observed 1.1 mm continuum, two CO lines (CO (4–3) and CO (3–2)) and the lower atomic carbon line transition ([CI](3P1-3P0)) at a few kpc (0″.3-0″.9) resolution. The primary targets are 25 star-forming galaxies selected as Hα emitters (HAEs) that are identified with a narrow band filter. These are massive galaxies with stellar masses of > 1010Mʘ that are mostly on the galaxy main sequence at z =2.5. We measure the molecular gas mass from the independent gas tracers of 1.1 mm, CO (3–2) and [CI], and investigate the gas kinematics of galaxies from CO (4–3). Molecular gas masses from the different measurements are consistent with each other for detection, with a gas fraction (fgas = Mgas/(Mgas+ Mstar)) of ≃ 0.5 on average but with a caveat. On the other hand, the CO line widths of the protocluster galaxies are typically broader by ˜50% compared to field galaxies, which can be attributed to more frequent, unresolved gas-rich mergers and/or smaller sizes than field galaxies, supported by our high-resolution images and a kinematic model fit of one of the galaxies. We discuss the expected scenario of galaxy evolution in protoclusters at high redshift but future large surveys are needed to get a more general view.

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Quenching by gas compression and consumption

Astronomy and Astrophysics ◽

10.1051/0004-6361/201834542 ◽

2019 ◽

Vol 624 ◽

pp. A81 ◽

Cited By ~ 4

Author(s):

Allison W. S. Man ◽

Matthew D. Lehnert ◽

Joël D. R. Vernet ◽

Carlos De Breuck ◽

Theresa Falkendal

Keyword(s):

Star Formation ◽

Formation Rate ◽

Relative Strength ◽

Star Formation History ◽

Molecular Gas ◽

Host Galaxies ◽

Massive Galaxies ◽

Star Forming ◽

Gas Compression ◽

Formation History

The objective of this work is to study how active galactic nuclei (AGN) influence star formation in host galaxies. We present a detailed investigation of the star-formation history and conditions of a z = 2.57 massive radio galaxy based on VLT/X-shooter and ALMA observations. The deep rest-frame ultraviolet spectrum contains photospheric absorption lines and wind features indicating the presence of OB-type stars. The most significantly detected photospheric features are used to characterize the recent star formation: neither instantaneous nor continuous star-formation history is consistent with the relative strength of the Si IIλ1485 and S Vλ1502 absorption. Rather, at least two bursts of star formation took place in the recent past, at 6+1-2 Myr and ≳20 Myr ago, respectively. We deduce a molecular H2 gas mass of (3.9 ± 1.0) × 1010 M⊙ based on ALMA observations of the [C I] 3P2−3P1 emission. The molecular gas mass is only 13% of its stellar mass. Combined with its high star-formation rate of (1020-170+190 M⊙ yr-1, this implies a high star-formation efficiency of (26 ± 8) Gyr−1 and a short depletion time of (38 ± 12) Myr. We attribute the efficient star formation to compressive gas motions in order to explain the modest velocity dispersions (⩽55 km s−1) of the photospheric lines and of the star-forming gas traced by [C I]. Because of the likely very young age of the radio source, our findings suggest that vigorous star formation consumes much of the gas and works in concert with the AGN to remove any residual molecular gas, and eventually quenching star formation in massive galaxies.

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