Kiloparsec-scale AGN outflows and feedback in merger-free galaxies
Abstract
ABSTRACT Recent observations and simulations have challenged the long-held paradigm that mergers are the dominant mechanism driving the growth of both galaxies and supermassive black holes (SMBH), in favour of non-merger (secular) processes. In this pilot study of merger-free SMBH and galaxy growth, we use Keck Cosmic Web Imager spectral observations to examine four low-redshift (0.043 < z < 0.073) disc-dominated ‘bulgeless’ galaxies hosting luminous active galactic nucleus (AGN), assumed to be merger-free. We detect blueshifted broadened [O iii] emission from outflows in all four sources, which the $$\mathrm{[O\, \small {III}]}$$/$$\rm {H}\beta$$ ratios reveal are ionized by the AGN. We calculate outflow rates in the range $$0.12{-}0.7~\rm {M}_{\odot }~\rm {yr}^{-1}$$, with velocities of $$675{-}1710~\rm {km}~\rm {s}^{-1}$$, large radial extents of $$0.6{-}2.4~\rm {kpc}$$, and SMBH accretion rates of $$0.02{-}0.07~\rm {M}_{\odot }~\rm {yr}^{-1}$$. We find that the outflow rates, kinematics, and energy injection rates are typical of the wider population of low-redshift AGN, and have velocities exceeding the galaxy escape velocity by a factor of ∼30, suggesting that these outflows will have a substantial impact through AGN feedback. Therefore, if both merger-driven and non-merger-driven SMBH growth lead to co-evolution, this suggests that co-evolution is regulated by feedback in both scenarios. Simulations find that bars and spiral arms can drive inflows to galactic centers at rates an order of magnitude larger than the combined SMBH accretion and outflow rates of our four targets. This work therefore provides further evidence that non-merger processes are sufficient to fuel SMBH growth and AGN outflows in disc galaxies.
- Publication Date:
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 1819469
- Resource Type:
- Published Article
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Additional Journal Information:
- Journal Name: Monthly Notices of the Royal Astronomical Society Journal Volume: 507 Journal Issue: 3; Journal ID: ISSN 0035-8711
- Publisher:
- Oxford University Press
- Country of Publication:
- United Kingdom
- Language:
- English
Citation Formats
Smethurst, R. J., Simmons, B. D., Coil, A., Lintott, C. J., Keel, W., Masters, K. L., Glikman, E., Leung, G. C. K., Shanahan, J., and Garland, I. L. Kiloparsec-scale AGN outflows and feedback in merger-free galaxies. United Kingdom: N. p., 2021.
Web. doi:10.1093/mnras/stab2340.
Smethurst, R. J., Simmons, B. D., Coil, A., Lintott, C. J., Keel, W., Masters, K. L., Glikman, E., Leung, G. C. K., Shanahan, J., & Garland, I. L. Kiloparsec-scale AGN outflows and feedback in merger-free galaxies. United Kingdom. https://doi.org/10.1093/mnras/stab2340
Smethurst, R. J., Simmons, B. D., Coil, A., Lintott, C. J., Keel, W., Masters, K. L., Glikman, E., Leung, G. C. K., Shanahan, J., and Garland, I. L. Mon .
"Kiloparsec-scale AGN outflows and feedback in merger-free galaxies". United Kingdom. https://doi.org/10.1093/mnras/stab2340.
@article{osti_1819469,
title = {Kiloparsec-scale AGN outflows and feedback in merger-free galaxies},
author = {Smethurst, R. J. and Simmons, B. D. and Coil, A. and Lintott, C. J. and Keel, W. and Masters, K. L. and Glikman, E. and Leung, G. C. K. and Shanahan, J. and Garland, I. L.},
abstractNote = {ABSTRACT Recent observations and simulations have challenged the long-held paradigm that mergers are the dominant mechanism driving the growth of both galaxies and supermassive black holes (SMBH), in favour of non-merger (secular) processes. In this pilot study of merger-free SMBH and galaxy growth, we use Keck Cosmic Web Imager spectral observations to examine four low-redshift (0.043 < z < 0.073) disc-dominated ‘bulgeless’ galaxies hosting luminous active galactic nucleus (AGN), assumed to be merger-free. We detect blueshifted broadened [O iii] emission from outflows in all four sources, which the $\mathrm{[O\, \small {III}]}$/$\rm {H}\beta$ ratios reveal are ionized by the AGN. We calculate outflow rates in the range $0.12{-}0.7~\rm {M}_{\odot }~\rm {yr}^{-1}$, with velocities of $675{-}1710~\rm {km}~\rm {s}^{-1}$, large radial extents of $0.6{-}2.4~\rm {kpc}$, and SMBH accretion rates of $0.02{-}0.07~\rm {M}_{\odot }~\rm {yr}^{-1}$. We find that the outflow rates, kinematics, and energy injection rates are typical of the wider population of low-redshift AGN, and have velocities exceeding the galaxy escape velocity by a factor of ∼30, suggesting that these outflows will have a substantial impact through AGN feedback. Therefore, if both merger-driven and non-merger-driven SMBH growth lead to co-evolution, this suggests that co-evolution is regulated by feedback in both scenarios. Simulations find that bars and spiral arms can drive inflows to galactic centers at rates an order of magnitude larger than the combined SMBH accretion and outflow rates of our four targets. This work therefore provides further evidence that non-merger processes are sufficient to fuel SMBH growth and AGN outflows in disc galaxies.},
doi = {10.1093/mnras/stab2340},
journal = {Monthly Notices of the Royal Astronomical Society},
number = 3,
volume = 507,
place = {United Kingdom},
year = {Mon Aug 16 00:00:00 EDT 2021},
month = {Mon Aug 16 00:00:00 EDT 2021}
}
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Works referenced in this record:
Stellar feedback in galaxies and the origin of galaxy-scale winds: Stellar feedback and galactic winds
journal, March 2012
- Hopkins, Philip F.; Quataert, Eliot; Murray, Norman
- Monthly Notices of the Royal Astronomical Society, Vol. 421, Issue 4
The Astropy Project: Building an Open-science Project and Status of the v2.0 Core Package
journal, August 2018
- Price-Whelan, A. M.; Sipőcz, B. M.; Günther, H. M.
- The Astronomical Journal, Vol. 156, Issue 3
Normal black holes in bulge-less galaxies: the largely quiescent, merger-free growth of black holes over cosmic time
journal, February 2018
- Martin, G.; Kaviraj, S.; Volonteri, M.
- Monthly Notices of the Royal Astronomical Society, Vol. 476, Issue 2
Deconstructing the narrow-line region of the nearest obscured quasar
journal, September 2015
- Villar Martín, M.; Bellocchi, E.; Stern, J.
- Monthly Notices of the Royal Astronomical Society, Vol. 454, Issue 1
Recalibration of the M BH – σ ⋆ Relation for AGN
journal, March 2017
- Batiste, Merida; Bentz, Misty C.; Raimundo, Sandra I.
- The Astrophysical Journal, Vol. 838, Issue 1
Bar‐driven Mass Inflow: How Bar Characteristics Affect the Inflow
journal, January 2004
- Regan, Michael W.; Teuben, Peter J.
- The Astrophysical Journal, Vol. 600, Issue 2
OUTFLOWS FROM ACTIVE GALACTIC NUCLEI: KINEMATICS OF THE NARROW-LINE AND CORONAL-LINE REGIONS IN SEYFERT GALAXIES ,
journal, September 2011
- Müller-Sánchez, F.; Prieto, M. A.; Hicks, E. K. S.
- The Astrophysical Journal, Vol. 739, Issue 2
Most Supermassive Black Holes Must Be Rapidly Rotating
journal, February 2002
- Elvis, M.; Risaliti, G.; Zamorani, G.
- The Astrophysical Journal, Vol. 565, Issue 2
Unification of the Fundamental Plane and Super Massive Black hole Masses
journal, November 2016
- Bosch, Remco C. E. van den
- The Astrophysical Journal, Vol. 831, Issue 2
An X-ray/SDSS sample: II. AGN-driven outflowing gas plasma properties
journal, October 2017
- Perna, M.; Lanzuisi, G.; Brusa, M.
- Astronomy & Astrophysics, Vol. 606
On the nature of the barlens component in barred galaxies: what do boxy/peanut bulges look like when viewed face-on?
journal, October 2015
- Athanassoula, E.; Laurikainen, E.; Salo, H.
- Monthly Notices of the Royal Astronomical Society, Vol. 454, Issue 4
Galaxy Zoo: evidence for rapid, recent quenching within a population of AGN host galaxies
journal, September 2016
- Smethurst, R. J.; Lintott, C. J.; Simmons, B. D.
- Monthly Notices of the Royal Astronomical Society, Vol. 463, Issue 3
The bolometric luminosity of type 2 AGN from extinction-corrected [OIII]: No evidence of Eddington-limited sources
journal, July 2009
- Lamastra, A.; Bianchi, S.; Matt, G.
- Astronomy & Astrophysics, Vol. 504, Issue 1
Quantifying the Fragility of Galactic Disks in Minor Mergers
journal, March 1996
- Walker, Ian R.; Mihos, J. Christopher; Hernquist, Lars
- The Astrophysical Journal, Vol. 460
Molecular gas in the central regions of the latest-type spiral galaxies
journal, July 2003
- Böker, T.; Lisenfeld, U.; Schinnerer, E.
- Astronomy & Astrophysics, Vol. 406, Issue 1
Spectral Energy Distributions and Multiwavelength Selection of Type 1 Quasars
journal, October 2006
- Richards, Gordon T.; Lacy, Mark; Storrie‐Lombardi, Lisa J.
- The Astrophysical Journal Supplement Series, Vol. 166, Issue 2
Transient spiral structure and the disc velocity substructure in Gaia DR2
journal, September 2018
- Hunt, Jason A. S.; Hong, Jack; Bovy, Jo
- Monthly Notices of the Royal Astronomical Society, Vol. 481, Issue 3
Driving gas shells with radiation pressure on dust in radiation-hydrodynamic simulations
journal, October 2017
- Costa, Tiago; Rosdahl, Joakim; Sijacki, Debora
- Monthly Notices of the Royal Astronomical Society, Vol. 473, Issue 3
The star Formation law in Nearby Galaxies on Sub-Kpc Scales
journal, November 2008
- Bigiel, F.; Leroy, A.; Walter, F.
- The Astronomical Journal, Vol. 136, Issue 6
Energy input from quasars regulates the growth and activity of black holes and their host galaxies
journal, February 2005
- Di Matteo, Tiziana; Springel, Volker; Hernquist, Lars
- Nature, Vol. 433, Issue 7026
The MAGNUM survey: different gas properties in the outflowing and disc components in nearby active galaxies with MUSE
journal, February 2019
- Mingozzi, M.; Cresci, G.; Venturi, G.
- Astronomy & Astrophysics, Vol. 622
Newborn spheroids at high redshift: when and how did the dominant, old stars in today's massive galaxies form?
journal, November 2012
- Kaviraj, S.; Cohen, S.; Ellis, R. S.
- Monthly Notices of the Royal Astronomical Society, Vol. 428, Issue 2
Bar formation as driver of gas inflows in isolated disc galaxies
journal, October 2015
- Fanali, R.; Dotti, M.; Fiacconi, D.
- Monthly Notices of the Royal Astronomical Society, Vol. 454, Issue 4
Black Hole Mass Scaling Relations for Spiral Galaxies. I. M BH – M *,sph
journal, March 2019
- Davis, Benjamin L.; Graham, Alister W.; Cameron, Ewan
- The Astrophysical Journal, Vol. 873, Issue 1
The growth of discs and bulges during hierarchical galaxy formation – I. Fast evolution versus secular processes
journal, April 2016
- Tonini, C.; Mutch, S. J.; Croton, D. J.
- Monthly Notices of the Royal Astronomical Society, Vol. 459, Issue 4
Determining Inclinations of Active Galactic Nuclei via Their Narrow-Line Region Kinematics. i. Observational Results
journal, October 2013
- Fischer, T. C.; Crenshaw, D. M.; Kraemer, S. B.
- The Astrophysical Journal Supplement Series, Vol. 209, Issue 1
Supermassive black holes in disc-dominated galaxies outgrow their bulges and co-evolve with their host galaxies
journal, May 2017
- Simmons, B. D.; Smethurst, R. J.; Lintott, C.
- Monthly Notices of the Royal Astronomical Society, Vol. 470, Issue 2
Planck 2015 results : XIII. Cosmological parameters
journal, September 2016
- Ade, P. A. R.; Aghanim, N.; Arnaud, M.
- Astronomy & Astrophysics, Vol. 594
On the Black Hole Mass-Bulge Mass Relation
journal, March 2004
- Hring, Nadine; Rix, Hans-Walter
- The Astrophysical Journal, Vol. 604, Issue 2
Feedback from active galactic nuclei: energy- versus momentum-driving
journal, September 2014
- Costa, Tiago; Sijacki, Debora; Haehnelt, Martin G.
- Monthly Notices of the Royal Astronomical Society, Vol. 444, Issue 3
Hydrodynamical Simulations of the Barred Spiral Galaxy ngc 1097
journal, June 2013
- Lin, Lien-Hsuan; Wang, Hsiang-Hsu; Hsieh, Pei-Ying
- The Astrophysical Journal, Vol. 771, Issue 1
How do Disks Survive Mergers?
journal, February 2009
- Hopkins, Philip F.; Cox, Thomas J.; Younger, Joshua D.
- The Astrophysical Journal, Vol. 691, Issue 2
Why do extremely massive disc galaxies exist today?
journal, April 2020
- Jackson, R. A.; Martin, G.; Kaviraj, S.
- Monthly Notices of the Royal Astronomical Society, Vol. 494, Issue 4
Disc galaxies formed from major mergers in Illustris
journal, February 2020
- Peschken, Nicolas; Łokas, Ewa L.; Athanassoula, E.
- Monthly Notices of the Royal Astronomical Society, Vol. 493, Issue 1
The Limited Impact of Outflows: Integral-field Spectroscopy of 20 Local AGNs
journal, March 2017
- Bae, Hyun-Jin; Woo, Jong-Hak; Karouzos, Marios
- The Astrophysical Journal, Vol. 837, Issue 1
Quantifying the Bimodal Color‐Magnitude Distribution of Galaxies
journal, January 2004
- Baldry, Ivan K.; Glazebrook, Karl; Brinkmann, Jon
- The Astrophysical Journal, Vol. 600, Issue 2
Spatially resolved star formation and fuelling in galaxy interactions
journal, October 2020
- Moreno, Jorge; Torrey, Paul; Ellison, Sara L.
- Monthly Notices of the Royal Astronomical Society, Vol. 503, Issue 3
RELIABLE IDENTIFICATIONS OF ACTIVE GALACTIC NUCLEI FROM THE WISE , 2MASS, AND ROSAT ALL-SKY SURVEYS
journal, May 2012
- Edelson, R.; Malkan, M.
- The Astrophysical Journal, Vol. 751, Issue 1
Present‐Day Growth of Black Holes and Bulges: The Sloan Digital Sky Survey Perspective
journal, September 2004
- Heckman, Timothy M.; Kauffmann, Guinevere; Brinchmann, Jarle
- The Astrophysical Journal, Vol. 613, Issue 1
Unraveling the Complex Structure of AGN-driven Outflows. III. The Outflow Size–Luminosity Relation
journal, September 2018
- Kang, Daeun; Woo, Jong-Hak
- The Astrophysical Journal, Vol. 864, Issue 2
Astropy: A community Python package for astronomy
journal, September 2013
- Robitaille, Thomas P.; Tollerud, Erik J.; Greenfield, Perry
- Astronomy & Astrophysics, Vol. 558
The Sloan Digital Sky Survey: Technical Summary
journal, September 2000
- York, Donald G.; Adelman, J.; Anderson, Jr., John E.
- The Astronomical Journal, Vol. 120, Issue 3
Estimating Black Hole Masses in Active Galaxies Using the Hα Emission Line
journal, September 2005
- Greene, Jenny E.; Ho, Luis C.
- The Astrophysical Journal, Vol. 630, Issue 1
Outflows in the inner kiloparsec of NGC 1566 as revealed by molecular (ALMA) and ionized gas (Gemini-GMOS/IFU) kinematics
journal, January 2019
- Slater, R.; Nagar, N. M.; Schnorr-Müller, A.
- Astronomy & Astrophysics, Vol. 621
Multi-scale simulations of black hole accretion in barred galaxies: Self-gravitating disk models
journal, June 2018
- Jung, M.; Illenseer, T. F.; Duschl, W. J.
- Astronomy & Astrophysics, Vol. 614
A Census of gas Outflows in type 2 Active Galactic Nuclei
journal, October 2014
- Bae, Hyun-Jin; Woo, Jong-Hak
- The Astrophysical Journal, Vol. 795, Issue 1
The physics of galactic winds driven by active galactic nuclei: AGN outflow physics
journal, July 2012
- Faucher-Giguère, Claude-André; Quataert, Eliot
- Monthly Notices of the Royal Astronomical Society, Vol. 425, Issue 1
The Two Micron All Sky Survey (2MASS)
journal, February 2006
- Skrutskie, M. F.; Cutri, R. M.; Stiening, R.
- The Astronomical Journal, Vol. 131, Issue 2
THE OBSERVED M -σ RELATIONS IMPLY THAT SUPER-MASSIVE BLACK HOLES GROW BY COLD CHAOTIC ACCRETION
journal, June 2012
- Nayakshin, Sergei; Power, Chris; King, Andrew R.
- The Astrophysical Journal, Vol. 753, Issue 1
Ionised outflows in z ~ 2.4 quasar host galaxies
journal, August 2015
- Carniani, S.; Marconi, A.; Maiolino, R.
- Astronomy & Astrophysics, Vol. 580
The Coevolution of Galaxies and Supermassive Black Holes: Insights from Surveys of the Contemporary Universe
journal, August 2014
- Heckman, Timothy M.; Best, Philip N.
- Annual Review of Astronomy and Astrophysics, Vol. 52, Issue 1
Molecular gas and star Formation in Nearby disk Galaxies
journal, June 2013
- Leroy, Adam K.; Walter, Fabian; Sandstrom, Karin
- The Astronomical Journal, Vol. 146, Issue 2
How to quench a galaxy
journal, October 2016
- Pontzen, Andrew; Tremmel, Michael; Roth, Nina
- Monthly Notices of the Royal Astronomical Society, Vol. 465, Issue 1
The Eighth data Release of the Sloan Digital sky Survey: First data from Sdss-Iii
journal, March 2011
- Aihara, Hiroaki; Allende Prieto, Carlos; An, Deokkeun
- The Astrophysical Journal Supplement Series, Vol. 193, Issue 2
The MOSDEF Survey: A Census of AGN-driven Ionized Outflows at z = 1.4–3.8
journal, November 2019
- Leung, Gene C. K.; Coil, Alison L.; Aird, James
- The Astrophysical Journal, Vol. 886, Issue 1
Building disc structure and galaxy properties through angular momentum: the Dark Sage semi-analytic model
journal, June 2016
- Stevens, Adam R. H.; Croton, Darren J.; Mutch, Simon J.
- Monthly Notices of the Royal Astronomical Society, Vol. 461, Issue 1
A Diversity of Progenitors and Histories for Isolated Spiral Galaxies
journal, August 2012
- Martig, Marie; Bournaud, Frédéric; Croton, Darren J.
- The Astrophysical Journal, Vol. 756, Issue 1
Galaxy Zoo: bulgeless galaxies with growing black holes
journal, January 2013
- Simmons, B. D.; Lintott, C.; Schawinski, K.
- Monthly Notices of the Royal Astronomical Society, Vol. 429, Issue 3
A Census of Ionized Gas Outflows in Type 1 AGNs: Gas Outflows in AGNs. V.
journal, September 2018
- Rakshit, Suvendu; Woo, Jong-Hak
- The Astrophysical Journal, Vol. 865, Issue 1
X-rays across the galaxy population – III. The incidence of AGN as a function of star formation rate
journal, January 2019
- Aird, J.; Coil, A. L.; Georgakakis, A.
- Monthly Notices of the Royal Astronomical Society, Vol. 484, Issue 3
Quasar feedback: more bang for your buck
journal, January 2010
- Hopkins, Philip F.; Elvis, Martin
- Monthly Notices of the Royal Astronomical Society, Vol. 401, Issue 1
Dynamics of dusty radiation-pressure-driven shells and clouds: fast outflows from galaxies, star clusters, massive stars, and AGN
journal, March 2015
- Thompson, Todd A.; Fabian, Andrew C.; Quataert, Eliot
- Monthly Notices of the Royal Astronomical Society, Vol. 449, Issue 1
The host galaxies and classification of active galactic nuclei
journal, November 2006
- Kewley, L. J.; Groves, B.; Kauffmann, G.
- Monthly Notices of the Royal Astronomical Society, Vol. 372, Issue 3
Kiloparsec-scale outflows are prevalent among luminous AGN: outflows and feedback in the context of the overall AGN population
journal, May 2014
- Harrison, C. M.; Alexander, D. M.; Mullaney, J. R.
- Monthly Notices of the Royal Astronomical Society, Vol. 441, Issue 4
A Catalog of Detailed Visual Morphological Classifications for 14,034 Galaxies in the Sloan Digital sky Survey
journal, February 2010
- Nair, Preethi B.; Abraham, Roberto G.
- The Astrophysical Journal Supplement Series, Vol. 186, Issue 2
The Multiphase Structure and Power Sources of Galactic Winds in Major Mergers
journal, April 2013
- Rupke, David S. N.; Veilleux, Sylvain
- The Astrophysical Journal, Vol. 768, Issue 1
The Demography of Massive Dark Objects in Galaxy Centers
journal, June 1998
- Magorrian, John; Tremaine, Scott; Richstone, Douglas
- The Astronomical Journal, Vol. 115, Issue 6
Secularly powered outflows from AGNs: the dominance of non-merger driven supermassive black hole growth
journal, September 2019
- Smethurst, R. J.; Simmons, B. D.; Lintott, C. J.
- Monthly Notices of the Royal Astronomical Society, Vol. 489, Issue 3
Erratum: Secularly powered outflows from AGNs: the dominance of non-merger driven supermassive black hole growth
journal, July 2021
- Smethurst, R. J.; Simmons, B. D.; Lintott, C. J.
- Monthly Notices of the Royal Astronomical Society, Vol. 506, Issue 3
RECALIBRATION OF THE VIRIAL FACTOR AND M BH -σ * RELATION FOR LOCAL ACTIVE GALAXIES
journal, October 2012
- Park, Daeseong; Kelly, Brandon C.; Woo, Jong-Hak
- The Astrophysical Journal Supplement Series, Vol. 203, Issue 1
The unorthodox evolution of major merger remnants into star-forming spiral galaxies
journal, June 2017
- Sparre, Martin; Springel, Volker
- Monthly Notices of the Royal Astronomical Society, Vol. 470, Issue 4
The Wide-Field Infrared Survey Explorer (Wise): Mission Description and Initial On-Orbit Performance
journal, November 2010
- Wright, Edward L.; Eisenhardt, Peter R. M.; Mainzer, Amy K.
- The Astronomical Journal, Vol. 140, Issue 6
The distribution of interstellar matter in the Scd galaxy NGC 6946. I - The neutral hydrogen disk
journal, September 1986
- Tacconi, L. J.; Young, J. S.
- The Astrophysical Journal, Vol. 308
Galaxy mergers in eagle do not induce a significant amount of black hole growth yet do increase the rate of luminous AGN
journal, April 2020
- McAlpine, Stuart; Harrison, Chris M.; Rosario, David J.
- Monthly Notices of the Royal Astronomical Society, Vol. 494, Issue 4
Ionized outflows in local luminous AGN: what are the real densities and outflow rates?
journal, September 2020
- Davies, R.; Baron, D.; Shimizu, T.
- Monthly Notices of the Royal Astronomical Society, Vol. 498, Issue 3
AGN outflows and feedback twenty years on
journal, February 2018
- Harrison, C. M.; Costa, T.; Tadhunter, C. N.
- Nature Astronomy, Vol. 2, Issue 3
Galaxy morphology in the ΛCDM cosmology
journal, July 2009
- Parry, O. H.; Eke, V. R.; Frenk, C. S.
- Monthly Notices of the Royal Astronomical Society, Vol. 396, Issue 4
Stellar and Molecular gas Kinematics of ngc 1097: Inflow Driven by a Nuclear Spiral
journal, August 2009
- Davies, R. I.; Maciejewski, W.; Hicks, E. K. S.
- The Astrophysical Journal, Vol. 702, Issue 1
Optical Classification of Southern Warm Infrared Galaxies
journal, January 2001
- Kewley, L. J.; Heisler, C. A.; Dopita, M. A.
- The Astrophysical Journal Supplement Series, Vol. 132, Issue 1