Letter | Published:

A giant protogalactic disk linked to the cosmic web

Nature volume 524, pages 192195 (13 August 2015) | Download Citation

Abstract

The specifics of how galaxies form from, and are fuelled by, gas from the intergalactic medium remain uncertain. Hydrodynamic simulations suggest that ‘cold accretion flows’—relatively cool (temperatures of the order of 104 kelvin), unshocked gas streaming along filaments of the cosmic web into dark-matter halos1,2,3—are important. These flows are thought to deposit gas and angular momentum into the circumgalactic medium, creating disk- or ring-like structures that eventually coalesce into galaxies that form at filamentary intersections4,5. Recently, a large and luminous filament, consistent with such a cold accretion flow, was discovered near the quasi-stellar object QSO UM287 at redshift 2.279 using narrow-band imaging6. Unfortunately, imaging is not sufficient to constrain the physical characteristics of the filament, to determine its kinematics, to explain how it is linked to nearby sources, or to account for its unusual brightness, more than a factor of ten above what is expected for a filament. Here we report a two-dimensional spectroscopic investigation of the emitting structure. We find that the brightest emission region is an extended rotating hydrogen disk with a velocity profile that is characteristic of gas in a dark-matter halo with a mass of 1013 solar masses. This giant protogalactic disk appears to be connected to a quiescent filament that may extend beyond the virial radius of the halo. The geometry is strongly suggestive of a cold accretion flow.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

References

  1. 1.

    & Virial shocks in galactic haloes? Mon. Not. R. Astron. Soc. 345, 349–364 (2003)

  2. 2.

    & Galaxy bimodality due to cold flows and shock heating. Mon. Not. R. Astron. Soc. 368, 2–20 (2006)

  3. 3.

    , , & How do galaxies get their gas? Mon. Not. R. Astron. Soc. 363, 2–28 (2005)

  4. 4.

    et al. Orbiting circumgalactic gas as a signature of cosmological accretion. Astrophys. J. 738, 39 (2011)

  5. 5.

    et al. Angular momentum acquisition in galaxy halos. Astrophys. J. 769, 74 (2013)

  6. 6.

    , , , & A cosmic web filament revealed in Lyman-α emission around a luminous high-redshift quasar. Nature 506, 63–66 (2014)

  7. 7.

    et al. The Cosmic Web Imager: an integral field spectrograph for the Hale telescope at Palomar Observatory: instrument design and first results. In Proc. SPIE, Ground-based and Airborne Instrumentation for Astronomy III (eds et al.) 77350P (SPIE, 2010)

  8. 8.

    et al. Intergalactic medium emission observations with the Cosmic Web Imager. I. The circum-QSO medium of QSO 1549+19, and evidence for a filamentary gas inflow. Astrophys. J. 786, 106 (2014)

  9. 9.

    et al. Intergalactic medium emission observations with the Cosmic Web Imager. II. Discovery of extended, kinematically linked emission around SSA22 Lyα blob 2. Astrophys. J. 786, 107 (2014)

  10. 10.

    et al. Resolving the galaxies within a giant Lyα nebula: witnessing the formation of a galaxy group? Astrophys. J. 752, 86 (2012)

  11. 11.

    , & Spatially resolved gas kinematics within a Lyα nebula: evidence for large-scale rotation. Astrophys. J. 799, 62 (2015)

  12. 12.

    et al. The 2013 release of Cloudy. Rev. Mex. Astron. Astrofis. 49, 137–163 (2013)

  13. 13.

    The photoevaporation of interstellar clouds. I. Radiation-driven implosion. Astrophys. J. 346, 735–755 (1989)

  14. 14.

    & Quasars probing quasars. IV. Joint constraints on the circumgalactic medium from absorption and emission. Astrophys. J. 766, 58 (2013)

  15. 15.

    The transfer of resonance-line radiation in static astrophysical media. Astrophys. J. 350, 216–241 (1990)

  16. 16.

    , , & The baryon content of cosmic structures. Astrophys. J. 708, L14–L17 (2010)

  17. 17.

    et al. A universal angular momentum profile for galactic halos. Astrophys. J. 555, 240–257 (2001)

  18. 18.

    , & The star formation law in atomic and molecular gas. Astrophys. J. 699, 850–856 (2009)

  19. 19.

    et al. Quasars probing quasars. VI. Excess H I absorption within one proper Mpc of z 2 quasars. Astrophys. J. 776, 136 (2013)

  20. 20.

    & Accurate sky subtraction of long-slit spectra: velocity dispersions at ΣV = 24.0 mag/arcsec2. Astron. J. 112, 797–805 (1996)

  21. 21.

    & Microslit nod-shuffle spectroscopy: a technique for achieving very high densities of spectra. Publ. Astron. Soc. Pacif. 113, 197–214 (2001)

  22. 22.

    et al. “Va-et-Vient” spectroscopy: a new mode for faint object CCD spectroscopy with very large telescopes. Astron. Astrophys. 281, 603–612 (1994)

  23. 23.

    , & A universal density profile from hierarchical clustering. Astrophys. J. 490, 493–508 (1997)

  24. 24.

    , , & Fluorescent Lyα emission from the high-redshift intergalactic medium. Astrophys. J. 628, 61–75 (2005)

  25. 25.

    , & Mapping neutral hydrogen during reionization with the Lyα emission from quasar ionization fronts. Astrophys. J. 672, 48–58 (2008)

  26. 26.

    Encounters of disk/halo galaxies. Astrophys. J. 331, 699–717 (1988)

  27. 27.

    & Tidal tailspin cold dark matter cosmologies. Mon. Not. R. Astron. Soc. 307, 162–178 (1999)

  28. 28.

    & Galactic bridges and tails. Astrophys. J. 178, 623–666 (1972)

  29. 29.

    , , & A cosmological framework for the co‐evolution of quasars, supermassive black holes, and elliptical galaxies. I. Galaxy mergers and quasar activity. Astrophys. J. 175 (Suppl.). 356–389 (2008)

  30. 30.

    , & Near‐infrared adaptive optics imaging of QSO host galaxies. Astrophys. J. 166 (Suppl.). 89–127 (2006)

  31. 31.

    Host galaxies of z 4.7 quasars. Astron. J. 125, 1053–1059 (2003)

  32. 32.

    , , & Host galaxies of two micron all sky survey-selected QSOs at redshift over 0.3. Astron. J. 131, 680–685 (2006)

  33. 33.

    , , , & Type I ultraluminous infrared galaxies: transition stage from ULIRGs to QSOs. Astrophys. J. 637, 104–113 (2006)

  34. 34.

    , & Evidence for quasar activity triggered by galaxy mergers in HST observations of dust‐reddened quasars. Astrophys. J. 674, 80–96 (2008)

  35. 35.

    , , & High-resolution H i mapping of NGC 4038/39 (“The Antennae”) and its tidal dwarf galaxy candidates. Astron. J. 122, 2969–2992 (2001)

Download references

Acknowledgements

We thank T. Tombrello and S. Kulkarni for their support of PCWI. This work was supported by the National Science Foundation and the California Institute of Technology.

Author information

Author notes

    • Daphne Chang

    Deceased.

Affiliations

  1. Cahill Center for Astrophysics, California Institute of Technology, 1216 East California Boulevard, Mail code 278-17, Pasadena, California 91125, USA

    • D. Christopher Martin
    • , Mateusz Matuszewski
    • , Patrick Morrissey
    •  & James D. Neill
  2. Caltech Optical Observatories, Cahill Center for Astrophysics, California Institute of Technology, 1216 East California Boulevard, Mail code 11-17, Pasadena, California 91125, USA

    • Anna Moore
  3. ETH Zurich, Institute for Astronomy, Wolfgang-Pauli-Strasse 27 8093, Zurich, Switzerland

    • Sebastiano Cantalupo
  4. Department of Astronomy and Astrophysics, University of California, 1156 High Street, Santa Cruz, California 95064, USA

    • J. Xavier Prochaska
  5. University of California Observatories, Lick Observatory, 1156 High Street, Santa Cruz, California 95064, USA

    • J. Xavier Prochaska

Authors

  1. Search for D. Christopher Martin in:

  2. Search for Mateusz Matuszewski in:

  3. Search for Patrick Morrissey in:

  4. Search for James D. Neill in:

  5. Search for Anna Moore in:

  6. Search for Sebastiano Cantalupo in:

  7. Search for J. Xavier Prochaska in:

  8. Search for Daphne Chang in:

Contributions

D.C.M. is the principal investigator of PCWI, led the observations and analysis of UM287, and was principal author on the paper. M.M., D.C., and P.M. designed, constructed, and operated PCWI. A.M. was the project and technical manager (2006–2010). J.D.N., M.M., and D.C.M. developed the PCWI/KCWI data pipeline and produced the final data cubes. M.M., P.M., S.C., and J.X.P. contributed Keck data and helped edit the paper.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to D. Christopher Martin.

Extended data

About this article

Publication history

Received

Accepted

Published

DOI

https://doi.org/10.1038/nature14616

Further reading

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.