Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

The formation of submillimetre-bright galaxies from gas infall over a billion years

Nature volume 525, pages 496–499 (2015)Cite this article

Subjects

Abstract

Submillimetre-bright galaxies at high redshift are the most luminous, heavily star-forming galaxies in the Universe1 and are characterized by prodigious emission in the far-infrared, with a flux of at least five millijanskys at a wavelength of 850 micrometres. They reside in haloes with masses about 1013 times that of the Sun2, have low gas fractions compared to main-sequence disks at a comparable redshift3, trace complex environments4,5 and are not easily observable at optical wavelengths6. Their physical origin remains unclear. Simulations have been able to form galaxies with the requisite luminosities, but have otherwise been unable to simultaneously match the stellar masses, star formation rates, gas fractions and environments7,8,9,10. Here we report a cosmological hydrodynamic galaxy formation simulation that is able to form a submillimetre galaxy that simultaneously satisfies the broad range of observed physical constraints. We find that groups of galaxies residing in massive dark matter haloes have increasing rates of star formation that peak at collective rates of about 500–1,000 solar masses per year at redshifts of two to three, by which time the interstellar medium is sufficiently enriched with metals that the region may be observed as a submillimetre-selected system. The intense star formation rates are fuelled in part by the infall of a reservoir gas supply enabled by stellar feedback at earlier times, not through major mergers. With a lifetime of nearly a billion years, our simulations show that the submillimetre-bright phase of high-redshift galaxies is prolonged and associated with significant mass buildup in early-Universe proto-clusters, and that many submillimetre-bright galaxies are composed of numerous unresolved components (for which there is some observational evidence11).

This is a preview of subscription content, access via your institution

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

Learn more

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Evolution of physical and observable properties of the submillimetre emission region and the central galaxy.
Figure 2: Surface density projection maps of the 250 kpc region around the central submillimetre galaxy for redshifts z ≈ 2–3.
Figure 3: Gas and stellar radius distribution for the central submillimetre galaxy.

References

  1. Casey, C. M., Narayanan, D. & Cooray, A. Dusty star-forming galaxies at high redshift. Phys. Rep. 541, 45–161 (2014)

    ADS  Google Scholar 

  2. Hickox, R. C. et al. The LABOCA survey of the Extended Chandra Deep Field-South: clustering of submillimetre galaxies. Mon. Not. R. Astron. Soc. 421, 284–295 (2012)

    ADS  Google Scholar 

  3. Geach, J. E. et al. On the evolution of the molecular gas fraction of star-forming galaxies. Astrophys. J. 730, L19 (2011)

    ADS  Google Scholar 

  4. Fu, H. et al. The rapid assembly of an elliptical galaxy of 400 billion solar masses at a redshift of 2.3. Nature 498, 338–341 (2013)

    CAS  PubMed  ADS  Google Scholar 

  5. Daddi, E. et al. Two bright submillimeter galaxies in a z = 4.05 protocluster in Goods-North, and accurate radio-infrared photometric redshifts. Astrophys. J. 694, 1517–1538 (2009)

    CAS  ADS  Google Scholar 

  6. Swinbank, A. M. et al. The rest-frame optical spectra of SCUBA galaxies. Astrophys. J. 617, 64–80 (2004)

    CAS  ADS  Google Scholar 

  7. Baugh, C. M. et al. Can the faint submillimetre galaxies be explained in the Λ cold dark matter model? Mon. Not. R. Astron. Soc. 356, 1191–1200 (2005)

    ADS  Google Scholar 

  8. Hayward, C. C. et al. Submillimetre galaxies in a hierarchical universe: number counts, redshift distribution and implications for the IMF. Mon. Not. R. Astron. Soc. 428, 2529–2547 (2013)

    ADS  Google Scholar 

  9. Shimizu, I., Yoshida, N. & Okamoto, T. Submillimetre galaxies in cosmological hydrodynamic simulations: source number counts and the spatial clustering. Mon. Not. R. Astron. Soc. 427, 2866–2875 (2012)

    ADS  Google Scholar 

  10. Davé, R. et al. The nature of submillimetre galaxies in cosmological hydrodynamic simulations. Mon. Not. R. Astron. Soc. 404, 1355–1368 (2010)

    ADS  Google Scholar 

  11. Hodge, J. A. et al. An ALMA survey of submillimeter galaxies in the extended Chandra Deep Field South: source catalog and multiplicity. Astrophys. J. 768, 91 (2013)

    ADS  Google Scholar 

  12. Hopkins, P. F. GIZMO: a new class of accurate, mesh-free hydrodynamic simulation methods. Mon. Not. R. Astron. Soc. 450, 53–110 (2015)

    CAS  ADS  Google Scholar 

  13. Davé, R., Finlator, K. & Oppenheimer, B. D. An analytic model for the evolution of the stellar, gas and metal content of galaxies. Mon. Not. R. Astron. Soc. 421, 98–107 (2012)

    ADS  Google Scholar 

  14. Hopkins, P. F. et al. Galaxies on FIRE (Feedback In Realistic Environments): stellar feedback explains cosmologically inefficient star formation. Mon. Not. R. Astron. Soc. 445, 581–603 (2014)

    CAS  ADS  Google Scholar 

  15. Feldmann, R. & Mayer, L. The Argo Simulation–I. Quenching of massive galaxies at high redshift as a result of cosmological starvation. Mon. Not. R. Astron. Soc. 446, 1939–1956 (2015)

    CAS  ADS  Google Scholar 

  16. Finkelstein, S. L. et al. A galaxy rapidly forming stars 700 million years after the Big Bang at redshift 7.51. Nature 502, 524–527 (2013)

    CAS  PubMed  ADS  Google Scholar 

  17. Weiß, A. et al. ALMA redshifts of millimeter-selected galaxies from the SPT survey: the redshift distribution of dusty star-forming galaxies. Astrophys. J. 767, 88 (2013)

    ADS  Google Scholar 

  18. Ivison, R. J. et al. Herschel-ATLAS: a binary HyLIRG pinpointing a cluster of starbursting protoellipticals. Astrophys. J. 772, 137 (2013)

    ADS  Google Scholar 

  19. Hezaveh, Y. D. et al. ALMA observations of SPT-discovered, strongly lensed, dusty, star-forming galaxies. Astrophys. J. 767, 132 (2013)

    ADS  Google Scholar 

  20. Downes, D. & Solomon, P. M. Rotating nuclear rings and extreme starbursts in ultraluminous galaxies. Astrophys. J. 507, 615–654 (1998)

    CAS  ADS  Google Scholar 

  21. Michałowski, M. J. et al. The stellar masses and specific star-formation rates of submillimetre galaxies. Astron. Astrophys. 541, A85 (2012)

    Google Scholar 

  22. Behroozi, P. S., Wechsler, R. H. & Conroy, C. The average star formation histories of galaxies in dark matter halos from z = 0–8. Astrophys. J. 770, 57 (2013)

    ADS  Google Scholar 

  23. Tacconi, L. J. et al. Phibss: Molecular gas content and scaling relations in z ∼ 1–3 massive, main-sequence star-forming galaxies. Astrophys. J. 768, 74 (2013)

    ADS  Google Scholar 

  24. Simpson, J. M. et al. The SCUBA-2 cosmology legacy survey: ALMA resolves the rest-frame far-infrared emission of sub-millimeter galaxies. Astrophys. J. 799, 81 (2015)

    ADS  Google Scholar 

  25. Kennicutt, R. C. & Evans, N. J. Star formation in the Milky Way and nearby galaxies. Annu. Rev. Astron. Astrophys. 50, 531–608 (2012)

    CAS  ADS  Google Scholar 

  26. van Dokkum, P. G. et al. Confirmation of the remarkable compactness of massive quiescent galaxies at z ∼ 2.3: early-type galaxies did not form in a simple monolithic collapse. Astrophys. J. 677, L5–L8 (2008)

    ADS  Google Scholar 

  27. Murray, S. G., Power, C. & Robotham, A. S. G. HMFcalc: an online tool for calculating dark matter halo mass functions. Astron. Comput. 3–4, 23–34 (2013)

    ADS  Google Scholar 

  28. Chapman, S. C., Blain, A. W., Smail, I. & Ivison, R. J. A redshift survey of the submillimeter galaxy population. Astrophys. J. 622, 772–796 (2005)

    CAS  ADS  Google Scholar 

  29. Riechers, D. A. et al. A dust-obscured massive maximum-starburst galaxy at a redshift of 6.34. Nature 496, 329–333 (2013)

    CAS  PubMed  ADS  Google Scholar 

  30. Vieira, J. D. et al. Dusty starburst galaxies in the early Universe as revealed by gravitational lensing. Nature 495, 344–347 (2013)

    CAS  PubMed  ADS  Google Scholar 

  31. Hopkins, P. F. A general class of Lagrangian smoothed particle hydrodynamics methods and implications for fluid mixing problems. Mon. Not. R. Astron. Soc. 428, 2840–2856 (2013)

    ADS  Google Scholar 

  32. Agertz, O. et al. Fundamental differences between SPH and grid methods. Mon. Not. R. Astron. Soc. 380, 963–978 (2007)

    MATH  ADS  Google Scholar 

  33. Sijacki, D., Vogelsberger, M., Kereš, D., Springel, V. & Hernquist, L. Moving mesh cosmology: the hydrodynamics of galaxy formation. Mon. Not. R. Astron. Soc. 424, 2999–3027 (2012)

    ADS  Google Scholar 

  34. Hayward, C. C., Torrey, P., Springel, V., Hernquist, L. & Vogelsberger, M. Galaxy mergers on a moving mesh: a comparison with smoothed particle hydrodynamics. Mon. Not. R. Astron. Soc. 442, 1996–2016 (2014)

    ADS  Google Scholar 

  35. Faucher-Giguère, C.-A. et al. Neutral hydrogen in galaxy haloes at the peak of the cosmic star formation history. Mon. Not. R. Astron. Soc. 449, 987–1003 (2015)

    ADS  Google Scholar 

  36. Springel, V., Di Matteo, T. & Hernquist, L. Modelling feedback from stars and black holes in galaxy mergers. Mon. Not. R. Astron. Soc. 361, 776–794 (2005)

    ADS  Google Scholar 

  37. Barnes, J. E. Gravitational softening as a smoothing operation. Mon. Not. R. Astron. Soc. 425, 1104–1120 (2012)

    ADS  Google Scholar 

  38. Hahn, O. & Abel, T. Multi-scale initial conditions for cosmological simulations. Mon. Not. R. Astron. Soc. 415, 2101–2121 (2011)

    CAS  ADS  Google Scholar 

  39. Hopkins, P. F., Quataert, E. & Murray, N. Self-regulated star formation in galaxies via momentum input from massive stars. Mon. Not. R. Astron. Soc. 417, 950–973 (2011)

    ADS  Google Scholar 

  40. Hopkins, P. F., Quataert, E. & Murray, N. The structure of the interstellar medium of star-forming galaxies. Mon. Not. R. Astron. Soc. 421, 3488–3521 (2012)

    CAS  ADS  Google Scholar 

  41. Hopkins, P. F., Narayanan, D., Murray, N. & Quataert, E. Dense molecular gas: a sensitive probe of stellar feedback models. Mon. Not. R. Astron. Soc. 433, 69–77 (2013)

    CAS  ADS  Google Scholar 

  42. Hopkins, P. F. et al. Star formation in galaxy mergers with realistic models of stellar feedback and the interstellar medium. Mon. Not. R. Astron. Soc. 430, 1901–1927 (2013)

    ADS  Google Scholar 

  43. Hopkins, P. F. et al. Resolving the generation of starburst winds in Galaxy mergers. Mon. Not. R. Astron. Soc. 433, 78–97 (2013)

    ADS  Google Scholar 

  44. Narayanan, D. & Hopkins, P. F. Why is the Milky Way X-factor constant? Mon. Not. R. Astron. Soc. 433, 1223–1229 (2013)

    ADS  Google Scholar 

  45. Katz, N., Weinberg, D. H. & Hernquist, L. Cosmological simulations with TreeSPH. Astrophys. J. Suppl. Ser. 105, 19–35 (1996)

    CAS  ADS  Google Scholar 

  46. Ferland, G. J. et al. The 2013 Release of Cloudy. Rev. Mex. Astron. Astrofis. 49, 137–163 (2013)

    CAS  ADS  Google Scholar 

  47. Krumholz, M. R., McKee, C. F. & Tumlinson, J. The atomic-to-molecular transition in galaxies. I. An analytic approximation for photodissociation fronts in finite clouds. Astrophys. J. 689, 865–882 (2008)

    CAS  ADS  Google Scholar 

  48. Krumholz, M. R. & Gnedin, N. Y. A comparison of methods for determining the molecular content of model galaxies. Astrophys. J. 729, 36 (2011)

    ADS  Google Scholar 

  49. Hopkins, P. F., Narayanan, D. & Murray, N. The meaning and consequences of star formation criteria in galaxy models with resolved stellar feedback. Mon. Not. R. Astron. Soc. 432, 2647–2653 (2013)

    ADS  Google Scholar 

  50. Kroupa, P. The initial mass function of stars: evidence for uniformity in variable systems. Science 295, 82–91 (2002)

    CAS  PubMed  ADS  Google Scholar 

  51. Leitherer, C. et al. Starburst99: synthesis models for galaxies with active star formation. Astrophys. J. Suppl. Ser. 123, 3–40 (1999)

    CAS  ADS  Google Scholar 

  52. Mannucci, F., Della Valle, M. & Panagia, N. Two populations of progenitors for Type Ia supernovae? Mon. Not. R. Astron. Soc. 370, 773–783 (2006)

    ADS  Google Scholar 

  53. Bellovary, J. et al. The relative role of galaxy mergers and cosmic flows in feeding black holes. Astrophys. J. 779, 136 (2013)

    ADS  Google Scholar 

  54. Anglés-Alcázar, D. et al. Torque-limited growth of massive black holes in galaxies across cosmic time. Astrophys. J. 800, 127 (2015)

    ADS  Google Scholar 

  55. Hopkins, P. F., Kocevski, D. D. & Bundy, K. Do we expect most AGN to live in discs? Mon. Not. R. Astron. Soc. 445, 823–834 (2014)

    CAS  ADS  Google Scholar 

  56. Kocevski, D. D. et al. CANDELS: constraining the AGN-merger connection with host morphologies at z ∼ 2. Astrophys. J. 744, 148 (2012)

    ADS  Google Scholar 

  57. Treister, E., Schawinski, K., Urry, C. M. & Simmons, B. D. Major galaxy mergers only trigger the most luminous active galactic nuclei. Astrophys. J. 758, L39 (2012)

    ADS  Google Scholar 

  58. Governato, F. et al. The Local Group as a test of cosmological models. New Astron. Rev. 2, 91–106 (1997)

    Google Scholar 

  59. Stadel, J. G. Cosmological N-body Simulations and their Analysis. Ph.D. thesis, Univ. Washington (2001)

    Google Scholar 

  60. Thompson, R. pyGadgetReader: GADGET snapshot reader for python. Astrophysics Source Code Library 1411.001 (2014)

  61. Thompson, R. SPHGR: Smoothed-Particle Hydrodynamics Galaxy Reduction. Astrophysics Source Code Library 1502.012 (2015)

  62. Turk, M. J. et al. yt: A multi-code analysis toolkit for astrophysical simulation data. Astrophys. J. Suppl. Ser. 192, 9 (2011)

    ADS  Google Scholar 

  63. Conroy, C., Gunn, J. E. & White, M. The propagation of uncertainties in stellar population synthesis modeling. I. The relevance of uncertain aspects of stellar evolution and the initial mass function to the derived physical properties of galaxies. Astrophys. J. 699, 486–506 (2009)

    ADS  Google Scholar 

  64. Conroy, C. & Gunn, J. E. The propagation of uncertainties in stellar population synthesis modeling. III. Model calibration, comparison, and evaluation. Astrophys. J. 712, 833–857 (2010)

    CAS  ADS  Google Scholar 

  65. Robitaille, T. P. HYPERION: an open-source parallelized three-dimensional dust continuum radiative transfer code. Astron. Astrophys. 536, A79 (2011)

    ADS  Google Scholar 

  66. Lucy, L. B. Computing radiative equilibria with Monte Carlo techniques. Astron. Astrophys. 344, 282–288 (1999)

    ADS  Google Scholar 

  67. Weingartner, J. C. & Draine, B. T. Dust grain-size distributions and extinction in the Milky Way, Large Magellanic Cloud, and Small Magellanic Cloud. Astrophys. J. 548, 296–309 (2001)

    ADS  Google Scholar 

  68. Robitaille, T. P. et al. A self-consistent model of Galactic stellar and dust infrared emission and the abundance of polycyclic aromatic hydrocarbons. Astron. Astrophys. 545, A39 (2012)

    Google Scholar 

  69. Dwek, E. The evolution of the elemental abundances in the gas and dust phases of the galaxy. Astrophys. J. 501, 643–665 (1998)

    CAS  ADS  Google Scholar 

  70. Vladilo, G. Dust and elemental abundances in damped Lyα absorbers. Astrophys. J. 493, 583–594 (1998)

    CAS  ADS  Google Scholar 

  71. Watson, D. The Galactic dust-to-metals ratio and metallicity using gamma-ray bursts. Astron. Astrophys. 533, A16 (2011)

    ADS  Google Scholar 

  72. Pascucci, I. et al. The 2D continuum radiative transfer problem. Benchmark results for disk configurations. Astron. Astrophys. 417, 793–805 (2004)

    ADS  Google Scholar 

  73. Jonsson, P. SUNRISE: polychromatic dust radiative transfer in arbitrary geometries. Mon. Not. R. Astron. Soc. 372, 2–20 (2006)

    CAS  ADS  Google Scholar 

  74. Jonsson, P., Groves, B. A. & Cox, T. J. High-resolution panchromatic spectral models of galaxies including photoionization and dust. Mon. Not. R. Astron. Soc. 186 (2010)

  75. Torrey, P. et al. Synthetic galaxy images and spectra from the Illustris simulation. Mon. Not. R. Astron. Soc. 447, 2753–2771 (2015)

    CAS  ADS  Google Scholar 

  76. Ade, P. A. R. et al. Planck 2013 results. XVI. Cosmological parameters. Astron. Astrophys. 571, A16 (2014)

    Google Scholar 

  77. González, J. E., Lacey, C. G., Baugh, C. M. & Frenk, C. S. The role of submillimetre galaxies in hierarchical galaxy formation. Mon. Not. R. Astron. Soc. 413, 749–762 (2011)

    ADS  Google Scholar 

  78. Hainline, L. J. et al. The stellar mass content of submillimeter-selected galaxies. Astrophys. J. 740, 96 (2011)

    ADS  Google Scholar 

  79. Michałowski, M. J. et al. Determining the stellar masses of submillimetre galaxies: the critical importance of star formation histories. Astron. Astrophys. 571, A75 (2014)

    Google Scholar 

  80. Bothwell, M. S. et al. A survey of molecular gas in luminous sub-millimetre galaxies. Mon. Not. R. Astron. Soc. 429, 3047–3067 (2013)

    CAS  ADS  Google Scholar 

  81. Narayanan, D., Bothwell, M. & Davé, R. Galaxy gas fractions at high redshift: the tension between observations and cosmological simulations. Mon. Not. R. Astron. Soc. 426, 1178–1184 (2012)

    CAS  ADS  Google Scholar 

  82. Tacconi, L. J. et al. Submillimeter galaxies at z ∼ 2: evidence for major mergers and constraints on lifetimes, IMF, and CO-H2 conversion factor. Astrophys. J. 680, 246–262 (2008)

    CAS  ADS  Google Scholar 

  83. Chakrabarti, S., Fenner, Y., Cox, T. J., Hernquist, L. & Whitney, B. A. An evolutionary model for submillimeter galaxies. Astrophys. J. 688, 972–989 (2008)

    CAS  ADS  Google Scholar 

  84. Narayanan, D., Cox, T. J., Hayward, C. C., Younger, J. D. & Hernquist, L. The star-forming molecular gas in high-redshift submillimetre galaxies. Mon. Not. R. Astron. Soc. 400, 1919–1935 (2009)

    ADS  Google Scholar 

  85. Narayanan, D. et al. The formation of high-redshift submillimetre galaxies. Mon. Not. R. Astron. Soc. 401, 1613–1619 (2010)

    ADS  Google Scholar 

  86. Hayward, C. C. et al. What does a submillimeter galaxy selection actually select? The dependence of submillimeter flux density on star formation rate and dust mass. Astrophys. J. 743, 159 (2011)

    ADS  Google Scholar 

  87. Narayanan, D., Krumholz, M. R., Ostriker, E. C. & Hernquist, L. A general model for the CO–H2 conversion factor in galaxies with applications to the star formation law. Mon. Not. R. Astron. Soc. 421, 3127–3146 (2012)

    CAS  ADS  Google Scholar 

Download references

Acknowledgements

We thank M. J. Michałowski for providing observational data. Partial support for D.N. was provided by NSF AST-1009452, AST-1442650, NASA HST AR-13906.001 and a Cottrell College Science Award. P.H., C.H., M.T. and R.T. were funded by the Gordon and Betty Moore Foundation (GBMF4561 and grant no. 776). P.H. acknowledges the Alfred P. Sloan Foundation for support. C.-A.F.-G. was supported by NASA awards PF3-140106, NNX15AB22G and NSF AST-1412836. D.K. was supported by NSF AST-1412153. R.F. was supported by NASA HF-51304.01-A, and is a Hubble fellow. The simulations here were run on Stampede at TACC through NSF XSEDE allocations TG-AST120025, TG-AST130039 and TG-AST140023, NASA Pleiades, and the Haverford College cluster.

Author information

Authors and Affiliations

  1. Haverford College, 370 West Lancaster Avenue, Haverford, 19041, Pennsylvania, USA

    Desika Narayanan

  2. National Center for Supercomputing Applications, University of Illinois, 1205 West Clark Street, Urbana-Champaign, 61820, Illinois, USA

    Matthew Turk

  3. Department of Astronomy and Theoretical Astrophysics Center, University of California, Berkeley, 94720, California, USA

    Robert Feldmann

  4. Max Planck Institute for Astronomy, Konigstuhl 17, Heidelberg, D-69117, Germany

    Thomas Robitaille

  5. TAPIR, California Institute of Technology, MC 350-17, Pasadena, 91125, California, USA

    Philip Hopkins & Christopher Hayward

  6. University of the Western Cape, Bellville, 7535, Cape Town, South Africa

    Robert Thompson

  7. Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, 85721, Arizona, USA

    Robert Thompson & David Ball

  8. Harvard–Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, 02138, Massachusetts, USA

    Christopher Hayward

  9. Whitman College, 345 Boyer Avenue, Walla Walla, 99362, Washington, USA

    David Ball

  10. CIERA, Northwestern University, 2145 Sheridan Road, Evanston, 60208, Illinois, USA

    Claude-André Faucher-Giguère

  11. CASS, University of California, San Diego, 9500 Gilman Drive, La Jolla, 92093, California, USA

    Dušan Kereš

Authors
  1. Desika Narayanan
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Matthew Turk
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Robert Feldmann
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Thomas Robitaille
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Philip Hopkins
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Robert Thompson
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Christopher Hayward
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. David Ball
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. Claude-André Faucher-Giguère
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. Dušan Kereš
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

D.N. wrote the text, and led the radiative transfer simulations and analysis. D.N., M.T., T.R. and R.T. wrote the POWDERDAY software. R.T., C.H. and D.B. contributed to simulation analysis, and R.F., P.H., C.-A.F.-G. and D.K. performed the cosmological simulations.

Corresponding author

Correspondence to Desika Narayanan.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Extended data figures and tables

Extended Data Figure 1 Mass of reservoir gas in the central galaxy that will be consumed during SMG starburst as a function of z.

The colour scale denotes the median scale height from the galaxy centre of mass. The gas mass consumed during the starburst is calculated by tracking the evolution of gas particles that turn into stars during the SMG phase (z ≈ 2–2.7), and is only measured for the central galaxy itself (that is, gas ejected into the halo is not included). The SMG gas reservoir follows a cycle of being pushed outward followed by re-accretion.

Extended Data Figure 2 Distribution of flux density ratio of brightest component in submillimetre-luminous region to total flux density.

The average is shown with the vertical line. Submillimetre-luminous regions often break up into multiples. The region is generally dominated by one component, although smaller subhaloes can contribute on average ∼30% of the observed flux density. The normalization of the ordinate, P, is arbitrary.

Extended Data Figure 3 Gas surface density for the central submillimetre galaxy.

The blue histogram shows the distribution of gas surface densities (Σgas) during all phases (that is, all snapshots, Snaps), while the pink histogram shows the same for the submillimetre-luminous phase. The ordinate (N) is weighted by the time a galaxy spends in a given gas surface density bin, and the normalization is arbitrary. We predict that the submillimetre-luminous phases do not have dramatically different surface density distributions compared to the non-submillimetre-luminous phases. This prediction might have been tentatively observed1,87.

Extended Data Figure 4 Molecular gas fraction as a function of galaxy stellar mass.

Blue stars show individual snapshots of the central submillimetre galaxy, while red circles with error bars (1σ) show observations of BzK galaxies and SMGs with direct CO(J = 1–0) measurements (to avoid complications in converting from higher-lying CO rotational lines to the ground state for a mass conversion). (BzK galaxies are those that have been selected on the basis of their B, z and K band luminosities.) Both the observations and our model show a declining molecular gas fraction (fgas) with increasing galaxy mass (M*), with a typical range of fgas = 0.1–0.4 for galaxies of SMG mass.

Extended Data Figure 5 Predicted spectral energy distribution (SED) for the central submillimetre galaxy.

The ordinate shows the flux density in mJy, while the abscissa shows the wavelength in μm. The blue shaded region shows the range of SEDs for all simulation snapshots that satisfy the fiducial F850μm > 5 mJy submillimetre galaxy selection criteria, while the dark grey points with error bars (1σ) are a compilation of observed data. The individual coloured lines show the SEDs for individual submillimetre-luminous snapshots. The data and models are redshifted to a common redshift z = 2. The model and data compare well, and the model suggests a diverse range of SMG SEDs.

Extended Data Figure 6 Overestimate of the SFR of high-z SMGs.

The ordinate denotes the SFR as determined from the infrared SED (SFRIR)25, while the abscissa shows the SFR averaged over the last 50 Myr in the simulations (SFR50). Up to an SFR of ∼800 M⊙ yr−1 the two correspond well. At higher SFRs, however, there is a dramatic departure owing to substantial contribution to the infrared luminosity by older stars.

Extended Data Figure 7 Resolution tests for hydrodynamic zoom simulations.

Lines show the 850 μm duty cycle above a given flux density as a function of flux density for our resolution test models presented in Methods. SR denotes our standard resolution (the resolution of our main model) while HR is a one-level-higher refinement.

Extended Data Figure 8 Stellar mass–redshift relation for the model galaxy.

The purple line shows model results, while the dark-blue filled region shows observational constraints from an abundance matching assumption22. The model and observations are in reasonable agreement, especially during the submillimetre-luminous phase (vertical shaded region). At late times, the stellar mass of the galaxy is a factor of ∼2 higher than the median observed galaxy.

Extended Data Figure 9 Tests of parameter choices for radiative transfer calculations.

The simulated galaxy for these tests is our lowest resolution cosmological simulation (m13m14). Each panel shows the 850 μm flux density light curve of the tested model, with time noted on the abscissa (redshift on the bottom, time since the Big Bang on the top). In all panels, the shaded region denotes S850 ≥ 5 mJy, which is the canonical selection criteria for SMGs. Top left, our fiducial set of parameters; top right, simulation with a 100 kpc (on a side) emission region instead of 200 kpc; bottom left, simulation with our model for PAHs turned off; bottom right, fiducial simulation run with ten times the number of photons.

Extended Data Table 1 Summary of model galaxies
Full size table

PowerPoint slides

Rights and permissions

Reprints and Permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Narayanan, D., Turk, M., Feldmann, R. et al. The formation of submillimetre-bright galaxies from gas infall over a billion years. Nature 525, 496–499 (2015). https://doi.org/10.1038/nature15383

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature15383

This article is cited by

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing