Publications by Michele Cappellari


A black-hole mass measurement from molecular gas kinematics in NGC4526

Nature (2013)

TA Davis, M Bureau, M Cappellari, M Sarzi, L Blitz


AGN feedback driven molecular outflow in NGC 1266

Proceedings of the International Astronomical Union 8 (2012) 175-176

K Alatalo, KE Nyland, G Graves, S Deustua, J Wrobel, LM Young, TA Davis, M Bureau, E Bayet, L Blitz, M Bois, F Bournaud, M Cappellari, RL Davies, PT De Zeeuw, E Emsellem, S Khochfar, D Krajnovic, H Kuntschner, S Martín, RM Mcdermid, R Morganti, T Naab, M Sarzi, N Scott, P Serra, A Weijmans

NGC 1266 is a nearby field galaxy observed as part of the ATLAS 3D survey (Cappellari et al. 2011). NGC 1266 has been shown to host a compact (< 200 pc) molecular disk and a mass-loaded molecular outflow driven by the AGN (Alatalo et al. 2011). Very Long Basline Array (VLBA) observations at 1.65 GHz revealed a compact (diameter < 1.2 pc), high brightness temperature continuum source most consistent with a low-level AGN origin. The VLBA continuum source is positioned at the center of the molecular disk and may be responsible for the expulsion of molecular gas in NGC 1266. Thus, the candidate AGN-driven molecular outflow in NGC 1266 supports the picture in which AGNs do play a significant role in the quenching of star formation and ultimately the evolution of the red sequence of galaxies. © International Astronomical Union 2013.


Probing the mass assembly of massive nearby galaxies with deep imaging

Proceedings of the International Astronomical Union 8 (2012) 358-361

PA Duc, JC Cuillandre, K Alatalo, L Blitz, M Bois, F Bournaud, M Bureau, M Cappellari, P Côté, RL Davies, TA Davis, PT De Zeeuw, E Emsellem, L Ferrarese, E Ferriere, S Gwyn, S Khochfar, D Krajnovic, H Kuntschner, PY Lablanche, RM McDermid, L Michel-Dansac, R Morganti, T Naab, T Oosterloo, M Sarzi, N Scott, P Serra, A Weijmans, LM Young

According to a popular scenario supported by numerical models, the mass assembly and growth of massive galaxies, in particular the Early-Type Galaxies (ETGs), is, below a redshift of 1, mainly due to the accretion of multiple gas-poor satellites. In order to get observational evidence of the role played by minor dry mergers, we are obtaining extremely deep optical images of a complete volume limited sample of nearby ETGs. These observations, done with the CFHT as part of the ATLAS3D, NGVS and MATLAS projects, reach a stunning 28.5 - 29 mag.arcsec-2 surface brightness limit in the g' band. They allow us to detect the relics of past collisions such as faint stellar tidal tails as well as the very extended stellar halos which keep the memory of the last episodes of galactic accretion. Images and preliminary results from this on-going survey are presented, in particular a possible correlation between the fine structure index (which parametrizes the amount of tidal perturbation) of the ETGs, their stellar mass, effective radius and gas content. © 2013 International Astronomical Union.


Dynamical masses of early-type galaxies at z ∼ 2

Proceedings of the International Astronomical Union 8 (2012) 37-44

M Cappellari

The evolution of masses and sizes of passive (early-type) galaxies with redshift provides ideal constraints to galaxy formation models. These parameters can in principle be obtained for large galaxy samples from multi-band photometry alone. However the accuracy of photometric masses is limited by the non-universality of the IMF. Galaxy sizes can be biased at high redshift due to the inferior quality of the imaging data. Both problems can be avoided using galaxy dynamics, and in particular by measuring the galaxies stellar velocity dispersion. Here we provide an overview of the efforts in this direction. © 2013 International Astronomical Union.


Systematic variation of the stellar initial mass function in early-type galaxies.

Nature 484 (2012) 485-488

M Cappellari, RM McDermid, K Alatalo, L Blitz, M Bois, F Bournaud, M Bureau, AF Crocker, RL Davies, TA Davis, PT de Zeeuw, P-A Duc, E Emsellem, S Khochfar, D Krajnović, H Kuntschner, P-Y Lablanche, R Morganti, T Naab, T Oosterloo, M Sarzi, N Scott, P Serra, A-M Weijmans, LM Young

Much of our knowledge of galaxies comes from analysing the radiation emitted by their stars, which depends on the present number of each type of star in the galaxy. The present number depends on the stellar initial mass function (IMF), which describes the distribution of stellar masses when the population formed, and knowledge of it is critical to almost every aspect of galaxy evolution. More than 50 years after the first IMF determination, no consensus has emerged on whether it is universal among different types of galaxies. Previous studies indicated that the IMF and the dark matter fraction in galaxy centres cannot both be universal, but they could not convincingly discriminate between the two possibilities. Only recently were indications found that massive elliptical galaxies may not have the same IMF as the Milky Way. Here we report a study of the two-dimensional stellar kinematics for the large representative ATLAS(3D) sample of nearby early-type galaxies spanning two orders of magnitude in stellar mass, using detailed dynamical models. We find a strong systematic variation in IMF in early-type galaxies as a function of their stellar mass-to-light ratios, producing differences of a factor of up to three in galactic stellar mass. This implies that a galaxy's IMF depends intimately on the galaxy's formation history.


The SAURON project - XXI. The spatially resolved UV-line strength relations of early-type galaxies

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 423 (2012) 1921-1939

H Jeong, SK Yi, M Bureau, RL Davies, R Bacon, M Cappellari, PT de Zeeuw, E Emsellem, J Falcon-Barroso, D Krajnovic, H Kuntschner, RM McDermid, RF Peletier, M Sarzi, RCE van den Bosch, G van de Ven


Revealing the origin of the cold ISM in massive early-type galaxies

Proceedings of the International Astronomical Union 8 (2012) 324-327

TA Davis, K Alatalo, M Bureau, L Young, L Blitz, A Crocker, E Bayet, M Bois, F Bournaud, M Cappellari, RL Davies, PA Duc, PT De Zeeuw, E Emsellem, J Falcon-Barroso, S Khochfar, D Krajnovic, H Kuntschner, PY Lablanche, RM McDermid, R Morganti, T Naab, M Sarzi, N Scott, P Serra, A Weijmans

Recently, massive early-type galaxies have shed their red-and-dead moniker, thanks to the discovery that many host residual star formation. As part of the ATLAS-3D project, we have conducted a complete, volume-limited survey of the molecular gas in 260 local early-type galaxies with the IRAM-30m telescope and the CARMA interferometer, in an attempt to understand the fuel powering this star formation. We find that around 22% of early-type galaxies in the local volume host molecular gas reservoirs. This detection rate is independent of galaxy luminosity and environment. Here we focus on how kinematic misalignment measurements and gas-to-dust ratios can be used to put constraints on the origin of the cold ISM in these systems. The origin of the cold ISM seems to depend strongly on environment, with misaligned, dust poor gas (indicative of externally acquired material) being common in the field but completely absent in rich groups and in the Virgo cluster. Very massive galaxies also appear to be devoid of accreted gas. This suggests that in the field mergers and/or cold gas accretion dominate the gas supply, while in clusters internal secular processes become more important. This implies that environment has a strong impact on the cold gas properties of ETGs. © 2013 International Astronomical Union.


Parallel-sequencing of early-type and spiral galaxies

Proceedings of the International Astronomical Union Cambridge University Press 10 (2012) 330-

M Cappellari

Since Edwin Hubble introduced his famous tuning fork diagram more than 70 years ago, spiral galaxies and early-type galaxies (ETGs) have been regarded as two distinct families. The spirals are characterized by the presence of disks of stars and gas in rapid rotation, while the early-types are gas poor and described as spheroidal systems, with less rotation and often non-axisymmetric shapes. The separation is physically relevant as it implies a distinct path of formation for the two classes of objects. I will give an overview of recent findings, from independent teams, that motivated a radical revision to Hubble's classic view of ETGs. These results imply a much closer link between spiral galaxies and ETGs than generally assumed.


Gemini GMOS and WHT SAURON integral-field spectrograph observations of the AGN-driven outflow in NGC1266

Monthly Notices of the Royal Astronomical Society 426 (2012) 1574-1590

TA Davis, D Krajnović, RM McDermid, M Bureau, M Sarzi, K Nyland, K Alatalo, E Bayet, L Blitz, M Bois, F Bournaud, M Cappellari, A Crocker, RL Davies, PT de Zeeuw, PA Duc, E Emsellem, S Khochfar, H Kuntschner, PY Lablanche, R Morganti, T Naab, T Oosterloo, N Scott, P Serra, AM Weijmans, LM Young

We use the Spectrographic Areal Unit for Research on Optical Nebulae and Gemini Multi-Object Spectrograph integral-field spectrographs to observe the active galactic nucleus (AGN) powered outflow in NGC1266. This unusual galaxy is relatively nearby (D = 30Mpc), allowing us to investigate the process of AGN feedback in action. We present maps of the kinematics and line strengths of the ionized gas emission lines Hα, Hβ, [Oiii], [Oi], [Nii] and [Sii], and report on the detection of sodium D absorption. We use these tracers to explore the structure of the source, derive the ionized and atomic gas kinematics, and investigate the gas excitation and physical conditions. NGC1266 contains two ionized gas components along most lines of sight, tracing the ongoing outflow and a component closer to the galaxy systemic, the origin of which is unclear. This gas appears to be disturbed by a nascent AGN jet. We confirm that the outflow in NGC1266 is truly multiphase, containing radio plasma, atomic, molecular and ionized gas and X-ray emitting plasma. The outflow has velocities of up to ±900 km s -1 away from the systemic velocity and is very likely to remove significant amount of cold gas from the galaxy. The low-ionization nuclear emission region-like line emission in NGC1266 is extended, and it likely arises from fast shocks caused by the interaction of the radio jet with the interstellar medium. These shocks have velocities of up to 800 km s -1, which match well with the observed velocity of the outflow. Sodium D equivalent width profiles are used to set constraints on the size and orientation of the outflow. The ionized gas morphology correlates with the nascent radio jets observed in 1.4 and 5 GHz continuum emission, supporting the suggestion that an AGN jet is providing the energy required to drive the outflow. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS.


An oxford swift integral field spectroscopy study of 14 early-type galaxies in the coma cluster

Monthly Notices of the Royal Astronomical Society 425 (2012) 1521-1526

N Scott, R Houghton, RL Davies, M Cappellari, N Thatte, F Clarke, M Tecza

As a demonstration of the capabilities of the new Oxford SWIFT integral field spectrograph, we present first observations for a set of 14 early-type galaxies in the core of the Coma cluster. Our data consist of I- and z-band spatially resolved spectroscopy obtained with the Oxford SWIFT spectrograph, combined with r-band photometry from the Sloan Digital Sky Survey archive for 14 early-type galaxies. We derive spatially resolved kinematics for all objects from observations of the calcium triplet absorption features at ∼8500Å. Using this kinematic information we classify galaxies as either fast rotators or slow rotators. We compare the fraction of fast and slow rotators in our sample, representing the densest environment in the nearby Universe, to results from the ATLAS 3D survey, finding that the slow rotator fraction is ∼50per cent larger in the core of the Coma cluster than in the volume-limited ATLAS 3D sample, a 1.2σ increase given our selection criteria. Comparing our sample to the Virgo cluster core only (which is 24 times less dense than the Coma core) we find no evidence of an increase in the slow rotator fraction. Combining measurements of the effective velocity dispersion σ e with the photometric data we determine the Fundamental Plane for our sample of galaxies. We find that the use of the average velocity dispersion within 1 effective radius, σ e, reduces the residuals by 13per cent with respect to comparable studies using central velocity dispersions, consistent with other recent integral field Fundamental Plane determinations. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS.


The ATLAS project - XII. Recovery of the mass-to-light ratio of simulated early-type barred galaxies with axisymmetric dynamical models

Monthly Notices of the Royal Astronomical Society 424 (2012) 1495-1521

PY Lablanche, M Cappellari, E Emsellem, F Bournaud, L Michel-Dansac, K Alatalo, L Blitz, M Bois, M Bureau, RL Davies, TA Davis, PT de Zeeuw, PA Duc, S Khochfar, D Krajnović, H Kuntschner, R Morganti, RM McDermid, T Naab, T Oosterloo, M Sarzi, N Scott, P Serra, AM Weijmans, LM Young

We investigate the accuracy in the recovery of the stellar dynamics of barred galaxies when using axisymmetric dynamical models. We do this by trying to recover the mass-to-light ratio (M/L) and the anisotropy of realistic galaxy simulations using the Jeans Anisotropic Multi-Gaussian Expansion (JAM) modelling method. However, given that the biases we find are mostly due to an application of an axisymmetric modelling algorithm to a non-axisymmetric system and in particular to inaccuracies in the deprojected mass model, our results are relevant for general axisymmetric modelling methods. We run N-body collisionless simulations to build a library with various luminosity distribution, constructed to mimic real individual galaxies, with realistic anisotropy. The final result of our evolved library of simulations contains both barred and unbarred galaxies. The JAM method assumes an axisymmetric mass distribution, and we adopt a spatially constant M/L and anisotropy distributions. The models are fitted to two-dimensional maps of the second velocity moments of the simulations for various viewing angles [position angle (PA) of the bar and inclination of the galaxy]. We find that the inclination is generally well recovered by the JAM models, for both barred and unbarred simulations. For unbarred simulations the M/L is also accurately recovered, with negligible median bias and with a maximum one of just Δ(M/L) < 1.5 per cent when the galaxy is not too close to face on. At very low inclinations the M/L can be significantly overestimated (9 per cent in our tests, but errors can be larger for very face-on views). This is in agreement with previous studies. For barred simulations the M/L is on average (when PA = 45°) essentially unbiased, but we measure an over/underestimation of up to Δ(M/L) = 15 per cent in our tests. The sign of the M/L bias depends on the PA of the bar as expected: overestimation occurs when the bar is closer to end-on, due to the increased stellar motion along the line-of-sight, and underestimation otherwise. For unbarred simulations, the JAM models are able to recover the mean value of the anisotropy with bias, within the region constrained by the kinematics. However when a bar is present, or for nearly face-on models, the recovered anisotropy varies wildly, with biases up to Δβ z≈ 0.3. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS.


The ATLAS 3D project - XI. Dense molecular gas properties of CO-luminous early-type galaxies

Monthly Notices of the Royal Astronomical Society (2012)

A Crocker, M Krips, M Bureau, LM Young, TA Davis, E Bayet, K Alatalo, L Blitz, M Bois, F Bournaud, M Cappellari, RL Davies, PT de Zeeuw, P-A Duc, E Emsellem, S Khochfar, D Krajnović, H Kuntschner, P-Y Lablanche, RM Mcdermid, R Morganti, T Naab, T Oosterloo, M Sarzi, N Scott, P Serra, A-M Weijmans


Deep near-infrared spectroscopy of passively evolving galaxies at z≳1.4

Astrophysical Journal 755 (2012)

M Onodera, A Renzini, M Carollo, M Cappellari, C Mancini, V Strazzullo, E Daddi, N Arimoto, R Gobat, Y Yamada, HJ McCracken, O Ilbert, P Capak, A Cimatti, M Giavalisco, AM Koekemoer, X Kong, S Lilly, K Motohara, K Ohta, DB Sanders, N Scoville, N Tamura, Y Taniguchi

We present the results of new near-IR spectroscopic observations of passive galaxies at z ≳ 1.4 in a concentration of BzK-selected galaxies in the COSMOS field. The observations have been conducted with Subaru/MOIRCS, and have resulted in absorption lines and/or continuum detection for 18 out of 34 objects. This allows us to measure spectroscopic redshifts for a sample that is almost complete to K AB = 21. COSMOS photometric redshifts are found in fair agreement overall with the spectroscopic redshifts, with a standard deviation of 0.05; however, 30% of objects have photometric redshifts systematically underestimated by up to 25%. We show that these systematic offsets in photometric redshifts can be removed by using these objects as a training set. All galaxies fall in four distinct redshift spikes at z = 1.43, 1.53, 1.67, and 1.82, with this latter one including seven galaxies. SED fits to broadband fluxes indicate stellar masses in the range of 4-40 × 10 10 M and that star formation was quenched 1Gyr before the cosmic epoch at which they are observed. The spectra of several individual galaxies have allowed us to measure their HδF indices and the strengths of the 4000 Å break, which confirms their identification as passive galaxies, as does a composite spectrum resulting from the co-addition of 17 individual spectra. The effective radii of the galaxies have been measured on the COSMOS HST/ACS i F814W-band image, confirming the coexistence at these redshifts of passive galaxies, which are substantially more compact than their local counterparts with others that follow the local effective radius-stellar mass relation. For the galaxy with the best signal-to-noise spectrum we were able to measure a velocity dispersion of 270 ± 105kms-1 (error bar including systematic errors), indicating that this galaxy lies closely on the virial relation given its stellar mass and effective radius. © 2012 The American Astronomical Society. All rights reserved.


DEEP NEAR-INFRARED SPECTROSCOPY OF PASSIVELY EVOLVING GALAXIES AT z greater than or similar to 1.4

ASTROPHYSICAL JOURNAL 755 (2012) ARTN 26

M Onodera, A Renzini, M Carollo, M Cappellari, C Mancini, V Strazzullo, E Daddi, N Arimoto, R Gobat, Y Yamada, HJ McCracken, O Ilbert, P Capak, A Cimatti, M Giavalisco, AM Koekemoer, X Kong, S Lilly, K Motohara, K Ohta, DB Sanders, N Scoville, N Tamura, Y Taniguchi


The ATLAS(3D) project-XIII. Mass and morphology of HI in early-type galaxies as a function of environment

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 422 (2012) 1835-1862

P Serra, T Oosterloo, R Morganti, K Alatalo, L Blitz, M Bois, F Bournaud, M Bureau, M Cappellari, AF Crocker, RL Davies, TA Davis, PT de Zeeuw, P-A Duc, E Emsellem, S Khochfar, D Krajnovic, H Kuntschner, P-Y Lablanche, RM McDermid, T Naab, M Sarzi, N Scott, SC Trager, A-M Weijmans, LM Young


The ATLAS <sup>3D</sup> project - XI. Dense molecular gas properties of CO-luminous early-type galaxies

Monthly Notices of the Royal Astronomical Society 421 (2012) 1298-1314

A Crocker, M Krips, M Bureau, LM Young, TA Davis, E Bayet, K Alatalo, L Blitz, M Bois, F Bournaud, M Cappellari, RL Davies, PT de Zeeuw, PA Duc, E Emsellem, S Khochfar, D Krajnović, H Kuntschner, PY Lablanche, RM Mcdermid, R Morganti, T Naab, T Oosterloo, M Sarzi, N Scott, P Serra, AM Weijmans

Surveying 18 12CO-bright galaxies from the ATLAS 3D early-type galaxy sample with the Institut de Radio Astronomie Millimétrique (IRAM) 30-m telescope, we detect 13CO(1-0) and 13CO(2-1) in all 18 galaxies, HCN(1-0) in 12/18 and HCO +(1-0) in 10/18. We find that the line ratios 12CO(1-0)/ 13CO(1-0) and 12CO(1-0)/HCN(1-0) are clearly correlated with several galaxy properties: total stellar mass, luminosity-weighted mean stellar age, molecular-to-atomic gas ratio, dust temperature and dust morphology. We suggest that these correlations are primarily governed by the optical depth in the 12CO lines; interacting, accreting and/or starbursting early-type galaxies have more optically thin molecular gas while those with settled dust and gas discs host optically thick molecular gas. The ranges of the integrated line intensity ratios generally overlap with those of spirals, although we note some outliers in the 12CO(1-0)/ 13CO(1-0), 12CO(2-1)/ 13CO(2-1) and HCN/HCO +(1-0) ratios. In particular, three galaxies are found to have very low 12CO(1-0)/ 13CO(1-0) and 12CO(2-1)/ 13CO(2-1) ratios. Such low ratios may signal particularly stable molecular gas which creates stars less efficiently than 'normal' (i.e. below Schmidt-Kennicutt prediction), consistent with the low dust temperatures seen in these galaxies. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS.


A way to deal with the fringe-like pattern in VIMOS-IFU data

ASTRONOMY & ASTROPHYSICS 541 (2012) ARTN A82

C Lagerholm, H Kuntschner, M Cappellari, D Krajnovic, RM McDermid, M Rejkuba


Spatially resolved molecular gas in early-type galaxies

Proceedings of the International Astronomical Union Cambridge University Press (CUP) 10 (2012) 122-123

TA Davis, K Alatalo, M Bureau, L Young, L Blitz, A Crocker, E Bayet, M Bois, F Bournaud, M Cappellari, RL Davies, P-A Duc, PT de Zeeuw, E Emsellem, J Falcon-Barroso, S Khochfar, D Krajnovic, H Kuntschner, P-Y Lablanche, RM McDermid, R Morganti, T Naab, M Sarzi, N Scott, P Serra, A Weijmans

<jats:title>Abstract</jats:title><jats:p>In around ≈25% of early-type galaxies (ETGs) UV emission from young stellar populations is present. Molecular gas reservoirs have been detected in these systems (e.g. Young <jats:italic>et al.</jats:italic> (2011), providing the fuel for this residual star-formation. The environment in which this molecular gas is found is quite different than that in spiral galaxies however, with harsher radiation fields, deeper potentials and high metallicity and alpha-element abundances. Here we report on one element of our multi-faceted programme to understand the similarities and differences between the gas reservoirs in spirals and ETGs. We use spatially resolved observations from the CARMA mm-wave interferometer to investigate the size of the molecular reservoirs in the the CO-rich ATLAS<jats:sup>3D</jats:sup> ETGs (survey described in Alatalo <jats:italic>et al.</jats:italic> 2012, submitted). We find that the molecular gas extent is smaller in absolute terms in ETGs than in late-type galaxies, but that the size distributions are similar once scaled by the galaxies optical/stellar characteristic scale-lengths (Fig 1, left). Amongst ETGs, we find that the extent of the molecular gas is independent of the kinematic misalignment, despite the many reasons why misaligned gas might have a smaller extent. The extent of the molecular gas does depend on environment, with Virgo cluster ETGs having less extended molecular gas reservoirs (Fig 1, right). Whatever the cause, this further emphases that cluster ETGs follow different evolutionary pathways from those in the field. Full details of this work will be presented in Davis <jats:italic>et al.</jats:italic> (2012), submitted.</jats:p>


Stellar discs in massive galaxies

Proceedings of the International Astronomical Union Cambridge University Press (CUP) 8 (2012) 314-314

D Krajnović, K Alatalo, L Blitz, M Bois, F Bournaud, M Bureau, M Cappellari, RL Davies, TA Davis, PT de Zeeuw, E Emsellem, S Khochfar, H Kuntschner, RM McDermid, R Morganti, T Naab, M Sarzi, N Scott, P Serra, A Weijmans, LM Young

<jats:p>Excluding those unsettled systems undergoing mergers, bright galaxies come in two flavours: with and without discs. In this work we look for photometric evidence for presence of discs and compare it with kinematic results of the ATLAS<jats:sup>3D</jats:sup> survey (Cappellari <jats:italic>et al</jats:italic>. 2011). We fit a Sérsic (1968) function to azimuthally averaged light profiles of ATLAS<jats:sup>3D</jats:sup> galaxies to derive single component fits and, subsequently, we fit a combination of the Sérsic function (free index <jats:italic>n</jats:italic>) and an exponential function (<jats:italic>n</jats:italic>=1) with the purpose of decomposing the light profiles into “bulge” and “disc” components (B+D model) of all non-barred sample galaxies. We compare the residuals of the B+D models with those of the single Sérsic fits and select the B+D model as preferred only when the improvement is substantial and there are no correlations within residuals. We find that the high angular momentum objects (fast rotators) are disc dominated systems with bulges of typically low <jats:italic>n</jats:italic> (when their light profiles can be decomposed) or are best represented with a single Sérsic function with a low Sérsic index (<jats:italic>n</jats:italic>&lt;3). Single component systems with large Sérsic indices are characteristic of low angular momentum objects (slow rotators).</jats:p>


Quenching of Star Formation in Molecular Outflow Host NGC 1266

Proceedings of the International Astronomical Union Cambridge University Press (CUP) 8 (2012) 371-371

K Alatalo, KE Nyland, G Graves, S Deustua, LM Young, TA Davis, AF Crocker, M Bureau, E Bayet, L Blitz, M Bois, F Bournaud, M Cappellari, RL Davies, PT de Zeeuw, E Emsellem, S Khochfar, D Krajnovic, H Kuntschner, RM McDermid, R Morganti, T Naab, T Oosterloo, M Sarzi, N Scott, P Serra, A Weijmans

<jats:title>Abstract</jats:title><jats:p>We detail the rich molecular story of NGC 1266, its serendipitous discovery within the ATLAS<jats:sup>3D</jats:sup> survey (Cappellari <jats:italic>et al</jats:italic>. 2011) and how it plays host to an AGN-driven molecular outflow, potentially quenching all of its star formation (SF) within the next 100 Myr. While major mergers appear to play a role in instigating outflows in other systems, deep imaging of NGC 1266 as well as stellar kinematic observations from <jats:monospace>SAURON</jats:monospace>, have failed to provide evidence that NGC 1266 has recently been involved in a major interaction. The molecular gas and the instantaneous SF tracers indicate that the current sites of star formation are located in a hypercompact disk within 200 pc of the nucleus (Fig. 1; SF rate ≈ 2 <jats:italic>M</jats:italic><jats:sub>⊙</jats:sub> yr<jats:sup>−1</jats:sup>). On the other hand, tracers of <jats:italic>recent</jats:italic> star formation, such as the Hβ absorption map from <jats:monospace>SAURON</jats:monospace> and stellar population analysis show that the young stars are distributed throughout a larger area of the galaxy than current star formation. As the AGN at the center of NGC 1266 continues to drive cold gas out of the galaxy, we expect star formation rates to decline as the star formation is ultimately quenched. Thus, NGC 1266 is in the midst of a key portion of its evolution and continued studies of this unique galaxy may help improve our understanding of how galaxies transition from the blue to the red sequence (Alatalo <jats:italic>et al</jats:italic>. 2011).</jats:p>

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