Data and Results

We will make a big effort to release high-level data products and scripts from our survey (e.g., radio images, reduced data cubes). Information of our papers and where to find the data products are found here.

  • Girdhar+23: “The Quasar Feedback Survey: molecular gas affected by central outflows and by ~10 kpc radio lobes reveal dual feedback effects in `radio quiet’ quasars“
    This paper presents spatially-resolved CO(3-2) measurements from ALMA for 4 of the QFeedS targets, which have radio lobes on >10kpc scales. All four are classified as `radio quiet’ by traditional methods, but have known radio emission associated with the AGN. We investigate the distribution and kinematics of the molecular gas on both the central ~kpc scales and the larger ~10kpc scales.
  • Molyneux+23: “The Quasar Feedback Survey: characterising CO excitation in quasar host galaxies“
    This paper presents CO SLEDs for 17 Type 2 AGN from the survey, which also have MUSE data. Emission-line fluxes are obtained from ALMA/ACA and APEX, for CO(1-0), CO(2-1), CO(3-2), CO(6-5) and CO(7-6), although not all targets are covered in all transitions. Overall we find that the CO SLEDs are similar to low-redshift Ultra Luminous Infrared Galaxies, in line with their typical star-forming properties and are less excited that high redshift quasars.
  • Silpa,S.+22: “The Quasar Feedback Survey: Revealing the Interplay of Jets, Winds & Emission Line Gas in Type 2 Quasars with Radio Polarization”
    This paper looks at the spatially-resolved radio polarization measurements in five of the QFeedS targets, with four showing polarization. The polarization structures are compared to the ionised gas. We detect 0.5−1 per cent fractional polarization in the radio cores and a high fractional polarization (10−30 per cent) in the lobes of these sources. The current work demonstrates that the interplay of jets/winds and emission-line gas is most likely responsible for the nature of radio outflows in radio-quiet AGN.
  • Girdhar+22: “Quasar Feedback Survey: Multi-phase outflows, turbulence and evidence for feedback caused by low power radio jets inclined into the galaxy disk”
    This paper is a extensive multi-wavelength study of one target. Despite the powerful quasar, it is the small jets, inclined into the disk, that are driving outflows and high levels of turbulence in the interstellar medium. Evidence for feedback by the jets on the stellar kinematics is also observed.
  • Jarvis+21: “The Quasar Feedback Survey: Discovering hidden Radio-AGN and their connection to the host galaxy ionised gas”
    This paper introduces the full survey and presents VLA imaging for 42 quasars. The prevalence of radio emission associated with AGN is high, despite the sample being classified as ‘radio quiet’ using traditional classification schemes.
  • Jarvis+20: “High molecular gas content and star formation rates in local galaxies that host quasars, outflows, and jets“
    APEX CO(2-1) and CO(6-5) for 9 pilot quasars
  • Jarvis+19: “Prevalence of radio jets associated with galactic outflows and feedback from quasars“
    VLA+eMERLIN+GMOS/VIMOS data for 10 quasars (9 of which are part of the final Quasar Feedback Survey sample). These data reveal a high prevalence of radio jets interacting with the host galaxy ionised gas (despite the sources being traditionally classified as ‘radio quiet’).
  • Lansbury+18: “Storm in a Teacup: X-Ray View of an Obscured Quasar and Superbubble“
    Chandra data for Teacup AGN (J1430+1339). Signatures of hot gas bubbles are observed and the AGN appears to be more powerful than previously thought.
  • Harrison+15: “Storm in a “Teacup”: A Radio-quiet Quasar with ≈10 kpc Radio-emitting Bubbles and Extreme Gas Kinematics”
    VLA+VIMOS data for Teacup AGN (J1430+1339). This revealed the first evidence for giant radio bubbles and an inner ~kpc radio structure (jet?), causing high levels of disturbance in the ionised gas.

Girdhar+23
“The Quasar Feedback Survey: molecular gas affected by central outflows and by ~10 kpc radio lobes reveal dual feedback effects in `radio quiet’ quasars”

MNRAS, in press; arXiv: 2311.03453

This paper presents ALMA results of four QFeedS targets, which have radio lobes on >10kpc scales. All four are classified as `radio quiet’ by traditional methods, but have known radio emission associated with the AGN. We investigate the distribution and kinematics of the molecular gas, traced via CO(3-2), on both the central ~kpc scales and the larger ~10kpc scales. We find that 2/4 targets show filamentary structures wrapping around, and along, the expanding radio lobes. The properties of these structures are consistent with those seen in Brightest Cluster Galaxies (BCGs).

Multi-panel plot showing two galaxies for which large-scale molecular gas structures were identified. In the top row we show CO(3-2) maps, colour-coded by the bulk. These show central molecular gas disks, but also the filamentary molecular gas structures, which are found along, and around the radio lobes. The bottom panels show CO emission-line profiles, extracted from the central regions of the galaxies. These show high velocity wing components, expected to be associated with outflowing gas.

All four targets show central high-velocity wing components in the CO(3-2) emission-line profiles, consistent with central outflows. The properties of these kinematic components are consistent with those seen in other samples of AGN. In contrast to most previous work, we have simultaneously revealed the impact of large-scale radio lobes and central outflows on the molecular gas. This implies feedback effects on two spatial scales, in the same sources.

Velocity versus radial extent of the molecular gas structures investigated in this study. Data points are shown in two colours, orange representing “Broad CO Outflows” which have smaller spatial extents (~0.1kpc-1kpc) and one representing “CO Filaments”, which have larger extents (~1kpc-10kpc). The new data points from this study (shown as larger data points) fall in the same regions of the parameter space as the archival samples that have studied these features (smaller data points). We find both types of features in the same targets.

Molyneux+23
“The Quasar Feedback Survey: characterising CO excitation in quasar host galaxies”

MNRAS, in press; arXiv: 2310.10235 

DATA: A combined table containing all of the measured and derived quantities, plus all of the 1D spectra covering the various CO emission line transitions is available here at: data.ncl.ac.uk

In this paper we explore 17 type 2 QFeedS targets. Using APEX and ALMA ACA observations, we measure the total molecular gas content using the CO(1-0) emission and homogeneously sample the CO spectral line energy distributions (SLEDs), observing CO transitions (Jup = 1, 2, 3, 6, 7). We observe high r21 ratios (r21 = L’CO(2−1)/L’CO(1−0)) with a median r21 = 1.06, similar to local (U)LIRGs (with r21 ∼ 1) and higher than normal star-forming galaxies (with r21 ∼ 0.65). Despite the high r21 values, for the 7 targets with the required data we find low excitation in CO(6-5) and CO(7-6), unlike high redshift quasars in the literature, which are far more luminous and show higher line ratios. The ionised gas traced by [OIII] exhibit systematically higher velocities than the molecular gas traced by CO. We conclude that any effects of quasar feedback (e.g. via outflows and radio jets) do not have a significant instantaneous impact on the global molecular gas content and excitation and we suggest that it only occurs on more localised scales, as shown in our other work (e.g., Girdhar+22,23).

Bottom panels: Histograms to show the distribution of line ratios within our sample. Top panels: Violin plot showing the distribution of line ratio values from our sample and selected comparison samples including the median, 16th and 84th quartiles of data (ignoring upper limits). The violin plots shown in blue are those for our sample and are shown in the same colour in the corresponding histograms below. Individual high-z quasars from Carilli & Walter 2013 are shown by red diamond markers. Other literature samples of SFGs and (U)LIRGS are also shown for comparison (Greve et al. 2014; Lamperti et al. 2020; Leroy et al. 2022a; Montoya Arroyave et al. 2023)

Silpa,S.+22
“The Quasar Feedback Survey: revealing the interplay of jets, winds, and emission-line gas in type 2 quasars with radio polarization”

MNRAS, 513, 4208; arXiv:2204.05613

DATA: The Stokes I, Q, U images and spectral index maps (*_ap.fits, *_ap_Q.fits, *_ap_U.fits and *_alpha_blank.fits, respectively) of the 5 individual sources presented in this work and a rotation measure image of J0945+1737, are all available at: data.ncl.ac.uk.

We present results from a combined radio polarization and emission-line study of five type 2 QFeedS targets. These five sources are known to exhibit close association between radio structures and ionized gas morphology and kinematics. Four sources (J0945+1737, J1000+1242, J1356+1026, and J1430+1339) show polarization in the current data. J1010+1413 is the unpolarized source in our sample. We detect 0.5−1 per cent fractional polarization in the radio cores and a high fractional polarization (10−30 per cent) in the lobes of these sources. The morphological, spectral, and polarization properties suggest a jet origin for radio emission in J0945+1737, J1000+1242, J1010+1413, and J1430+1339 whereas the current data cannot fully discern the origin of radio emission (jet or wind) in J1356+1026. An anticorrelation between various polarized knots in the radio and [O III] emission is observed in our sources, similar to that observed in some radio-loud AGN in the literature. This suggests that the radio emission is likely to be depolarized by the emission-line gas. The current work demonstrates that the interplay of jets/winds and emission-line gas is most likely responsible for the nature of radio outflows in radio-quiet AGN.

Polarization data for the Teacup AGN taken from Silpa,S. et al. 2022.
Left: VLA 5 GHz, total intensity contours in black for J1430+1339 with red superimposed electric polarization vectors,. Right: gray-scale HST [O III] image. In the left panel, the length of the vectors are proportional to fractional polarization. In the right panel, the VLA 5 GHz A-array total intensity contours are in cyan with the polarization vectors proportional to polarised intensity. The radio structure follows the [O III] emitting gas; however, the location of the strongest radio polarization structures appear to be offset from the strongest [O III] emission, suggest depolarization by the emission-line gas.

Girdhar+22
“The Quasar Feedback Survey: Multi-phase outflows, turbulence and evidence for feedback caused by low power radio jets inclined into the galaxy disk”

MNRAS, 512, 1608; arXiv:2103.00014 

DATA: The VLA images are available a Newcastle University’s Data repository. The L-band images are available here; the C-band images are available here. Other data products/maps will be released in due course.

In this study we present multi-wavelength observations of one of the targets, J1316+1753, including MUSE, ALMA and VLA. The source has small (~1kpc) and low power (Pjet~10^44 erg/s) radio jets that are included into the host galaxy disk. Our data reveal that these jets are causing high levels of outflowing turbulent gas in both the ionised gas and the molecular gas. The ionised gas, traced via [O III], has velocity widths reaching ~1200 km/s, over (at least 7.5kpc). This gas is expanding in an apparent cone above and below the disk. The molecular gas, traced via CO(3-2), has smaller velocity widths of ~400 km/s and extended to about ~4.5kpc.  The jets are seen to be strongly interacting with the interstellar medium (ISM) through enhanced ionised emission and disturbed/depleted molecular gas at the jet termini.

We see further evidence for jet-induced feedback through significantly higher stellar velocity-dispersion aligned, and co-spatial with, the jet axis (<5 deg). We discuss how jet-induced feedback could be an important feedback mechanism even in bolometrically luminous ‘radio-quiet’ quasars.

A summary set of figures from Girdhar et al. 2022 for J1316+1753. The left-most panel is a schematic summary of the main findings of the study. The central panel is a stellar velocity dispersion map, not the enhanced stellar velocities along the jet axis. The right-upper panel is a velocity width map (W80) for the molecular gas (CO(3-2)), note the enhanced velocity dispersion expanding above the jet. The right-bottom panel is a velocity width map (W80) for the ionised gas ([O III]), note the cones of ~1000 km/s gas both above and below the jet axis.

Jarvis+21
“The Quasar Feedback Survey: Discovering hidden Radio-AGN and their connection to the host galaxy ionised gas”

MNRAS, 503, 1780; arXiv:2103.00014  and detailed supplementary information

DATA: The VLA images for the 42 objects from this study are available a Newcastle University’s Data repository. The L-band images are available here; the C-band images are available here and the in-band spectral index maps (from the C-band) are available here. Machine readable versions of the tables are available here.

In this paper we present an overview of the survey and VLA images a medium resolution (MR: 1″/L-band/1.4GHz) and high resolution (HR: 0.3″/C-band/6GHz), for all 42 quasars. We also compare these to the low resolution (LR) FIRST images. Example images are show in the figure below which gives an overview of the range of morphologies that we observe. We find that 67% of the sample show extended radio structures on ~1-60 kpc scales. Furthermore, by using a range of criteria, we find a surprisingly high fraction of Radio-AGN in our sample of quasars. At least 57% harbour a Radio-AGN, despite the fact that only 9-21% would be classified as Radio-AGN by traditional criteria. The origin of the radio emission in the remainder of the sample remains ambiguous.

Example VLA images
Example VLA images from Jarvis+21 to show the variety of morphologies seen across the different images: Low Resolution (LR; 1.4GHz, ~5″ resolution) images are overlaid with green contours, Medium Resolution (MR; 1.4GHz, ~1″ resolution) images are overlaid with blue contours and High Resolution (HR; 6GHz, ~0.3″ resolution) images are overlaid with black contours.

We also demonstrate a relationship between the radio emission and ionised gas properties (traced via [O III]). For example, we see a negative correlation between velocity width of the emission line and the size of the radio emission (see below). This has been observed previously in more powerful Radio-AGN, and is an indication that compact radio emission (either from jets or quasar winds) is having a dramatic impact on the host galaxy gas. Overall our paper shows the important or studying the radio emission at high spatial resolution to understand feedback from quasars – even for low radio luminosity (“radio quiet”) sources.

Figure from Jarvis+21. [O III] emission-line width (SDSS spectra) versus largest angular size measured from our radio images. In agreement with previous work on powerful radio galaxies we see a weak anti-correlation, possibly indicating impact by radio jets or winds when they are confined within the host galaxy.

Jarvis+20 (Pilot Study)
“High molecular gas content and star formation rates in local galaxies that host quasars, outflows, and jets”

MNRAS, 498, 1560 (2020), arXiv:2007.10351

DATA: The APEX spectra for the nine objects from this study are available a Newcastle University’s Data repository here . This includes the 9 targets with CO(2-1) emission-line data and the 3 targets with CO(6-5) emission-line data. We also provide a small python script to plot the data. Machine readable versions of the main tables can be found here. All data products available from this study are available at the following DOI link: https://doi.org/10.25405/data.ncl.c.5207720

Figure from Jarvis et al. 2019, MNRAS, 498, 1560 (2020), arXiv:2007.10351. The figure shows gas fractions (top row), star-formation efficiencies (bottom row) as a function of stellar mass (left), specific star formation rate (middle) and offset from the main sequence (right). Star-forming galaxies (with no AGN) are represented as green contours and data points, low power AGN as magenta squares and our sample as black circles.

In this paper we obtained APEX observations of the CO(2-1) emission line of the 9 pilot quasars and CO(6-5) emission line of a subset of 3 of these quasars. We used these observations to measure the total molecular gas content inside the host galaxies. We also used careful analyses of the spectral energy distributions to measure the star formation rates and stellar masses of the host galaxies. Our results show that these powerful quasars at z~0.1 live inside gas rich, star-forming galaxies. Their molecular gas properties and star-formation properties (i.e., their gas fractions and star formation efficiencies) are consistent with the overall galaxy population. Therefore, the jets and ionised outflows that are known to exist in these systems have had no immediate impact on the gas content or star formation rates, at least on a galaxy-wide scale. Furthermore the CO(6-5)/CO(2-1) emission-line ratios for the three objects with the measurement tentatively suggest no extreme excitation of the molecular gas. Nonetheless, we can not rule out that the jets or outflows will have an impact on longer timescales or that they have an impact on smaller, unresolved scales.

Jarvis+19 (Pilot Study)
“Prevalence of radio jets associated with galactic outflows and feedback from quasars”

MNRAS, 485, 2710J , (arXiv:1902.07727).
and detailed supplementary information

DATA: The main radio images (as shown in the figure below), the IFU data cubes and all of the derived [O III] property maps (e.g., velocities and velocity widths) for all 10 targets from this study are available at Newcastle University’s data repository. You can navigate to the individual target’s data products from the objects page or find them through the following DOI link: https://doi.org/10.25405/data.ncl.c.5203919

Figure from Jarvis et al. 2019, MNRAS, 485, 2710J , (arXiv:1902.07727). This shows [O III] images, tracing the warm ionised gas, in the background with contours showing the radio maps. Green contours show the low resolution (~1″) radio maps and blue contours the high resolution (~0.3″) radio maps. We not that different radio structures are apparent across the two sets of radio maps and there is a strong spatial connection between the radio and ionised gas emission.

Using the VLA radio interferometer we performed multi-resolution and multi-frequency observations of a sample of 10 quasars (i.e, the most rapidly growing black holes!) at redshift z<0.2. Despite these not being classified as “radio AGN” by most traditional methods, we found that the radio emission is dominated by the AGN (>~90%) in 9 of the 10 targets. Furthermore our high-resolution imaging revealed jet-like structures in at least 8 of these sources, indicating that radio jets are (perhaps surprisingly) prevalent in such systems. The figure shows the distribution of ionised gas ([O III] emission) in the background and the contours show the distribution of radio emission from our various observations.

Lansbury+18 (Pilot Study):
“Storm in a Teacup: X-ray view of an obscured quasar and superbubble“

ApJ,856L,1, arXiv:1803.00009 

DATA: The Chandra images and the XMM and Chandra spectra from this study are available to down load from Newcastle University’s data repository at DOI: https://doi.org/10.25405/data.ncl.13387625.v1

Figure from Lansbury et al. 2018, ApJL, 856, 1, arXiv:1803.00009

Using Chandra time the team observed the Teacup AGN, which we had previously identified as having large bubbles of ionised gas (green colour in image) and radio emission (red colour in image) to obtain spatially-resolved X-ray measurements. Using these data, in combination with existing XMM-Newton X-ray observations , we obtained the best constraints to date on the bolometric output (and level of obscuring material) of the growing supermassive black hole at the centre of this galaxy. These results revealed that the quasar may not be “fading away” as previously thought, based on earlier less robust constraints on the bolometric output. Furthermore, in the Chandra data we detected the large bubble in X-ray emission (see blue contours in image), providing tentative evidence for a very hot outflowing gas component within the bubble. This source appears to be showing outflows in multiple phases of gas, driven by the supermassive black hole lurking at its centre.

Chandra Popular Releases about publication:

Harrison+15 (Pilot Study)
“Storm in a ‘Teacup’: A Radio-quiet Quasar with ≈10 kpc Radio-emitting Bubbles and Extreme Gas Kinematics“
ApJ, 800, 45 (2015), (arXiv:1410.4198)

DATA: The various radio images used in Harrison+15 are available from Newcastle University’s data repository, here. The DOI link is: https://doi.org/10.25405/data.ncl.13251731

Figure from Harrison et al. 2015, ApJ, 800, 45 (2015), (arXiv:1410.4198).

Using the VLA radio interferometer we performed multi-resolution and multi-frequency observations of the Teacup AGN; a z=0.1 radio-quiet quasar. The Teacup AGN was observed by us in 2014 to have a high-velocity gas component ~1kpc from the central core. This is seen in the high-velocity wing of the [O III] emission-line profile at this location (see the inset spectrum at the bottom of the image). Additionally, HST narrow-band imaging reveals a ~10kpc arc of ionised gas to the East (see image). Our new VLA data revealed that both the high-velocity outflow and ionised arc are associated with radio emission. Our interpretation of these results is that a radio jet (or possibly quasar wind) is interacting with the gas ~1kpc from the core and driving the high-velocity outflow. Additionally there are bi-polar radio bubbles being inflated by the central AGN that are interacting with the gas on ~10-12kpc scales. This AGN is “radio-quiet”, which means that its radio luminosity is typical for its optical radio luminosity, and is therefore more representative of the overall population than radio-loud AGN. Our results show in the importance of radio observations for understanding AGN feedback for systems with low radio luminosities.  This is the first object from the larger sample that is presented in Jarvis+19,20.