Star formation in NGC 5194 (M51a). II. The spatially resolved star formation law

R.C. C. Kennicutt; D. Calzeti; F. Walter; G. Helou; D.J. J. Hollenbach; L. Armus; G. Bendo; D.A. A. Dale; B.T. T. Draine; C.W. W. Engelbracht; K.D. D. Gordon; M.K.M. K.M. Prescott; M.W. W. Regan; M.D. D. Thornley; C. Bot; E. Brinks; E. De Blok; D. De Mello; Martin Meyer; J. Moustakas; E.J. J. Murphy; K. Sheth; J.D.T. D.T. Smith

doi:10.1086/522300

Star formation in NGC 5194 (M51a). II. The spatially resolved star formation law

R.C. C. Kennicutt, D. Calzeti, F. Walter, G. Helou, D.J. J. Hollenbach, L. Armus, G. Bendo, D.A. A. Dale, B.T. T. Draine, C.W. W. Engelbracht, K.D. D. Gordon, M.K.M. K.M. Prescott, M.W. W. Regan, M.D. D. Thornley, C. Bot, E. Brinks, E. De Blok, D. De Mello, Martin Meyer, J. MoustakasE.J. J. Murphy, K. Sheth, J.D.T. D.T. Smith

International Centre for Radio Astronomy Research (ICRAR)

Research output: Contribution to journal › Article › peer-review

398 Citations (Scopus)

Abstract

We have studied the relationship between the star formation rate (SFR), surface density, and gas surface density in the spiral galaxy M51a (NGC 5194), using multiwavelength data obtained as part of the Spitzer Infrared Nearby Galaxies Survey (SINGS ). We introduce a new SFR index based on a linear combination of Ha emission-line and 24 µm continuum luminosities, which provides reliable extinction-corrected ionizing fluxes and SFR densities over a wide range of dust attenuations. The combination of these extinction-corrected SFR densities with aperture synthesis H I and CO maps has allowed us to probe the form of the spatially resolved star formation law on scales of 0.5-2 kpc. We find that the resolved SFR versus gas surface density relation is well represented by a Schmidt power law, which is similar in form and dispersion to the disk-averaged Schmidt law. We observe a comparably strong correlation of the SFR surface density with the molecular gas surface density, but no significant correlation with the surface density of atomic gas. The best-fitting slope of the Schmidt law varies from N = 1.37 to 1.56, with zero point and slope that change systematically with the spatial sampling scale. We tentatively attribute these variations to the effects of areal sampling and averaging of a nonlinear intrinsic star formation law. Our data can also be fitted by an alternative parameterization of the SFR surface density in terms of the ratio of gas surface density to local dynamical time, but with a considerable dispersion. © 2007. The American Astronomical Society. All rights reserved.

Original language	English
Pages (from-to)	333-348
Number of pages	16
Journal	The Astrophysical Journal
Volume	671
Issue number	1
DOIs	https://doi.org/10.1086/522300
Publication status	Published - 2007

Access to Document

10.1086/522300

Cite this

Kennicutt, R. C. C., Calzeti, D., Walter, F., Helou, G., Hollenbach, D. J. J., Armus, L., Bendo, G., Dale, D. A. A., Draine, B. T. T., Engelbracht, C. W. W., Gordon, K. D. D., Prescott, M. K. M. K. M., Regan, M. W. W., Thornley, M. D. D., Bot, C., Brinks, E., De Blok, E., De Mello, D., Meyer, M., ... Smith, J. D. T. D. T. (2007). Star formation in NGC 5194 (M51a). II. The spatially resolved star formation law. The Astrophysical Journal, 671(1), 333-348. https://doi.org/10.1086/522300

@article{870f43e7ba564f0abe63dbd1573f5bd0,

title = "Star formation in NGC 5194 (M51a). II. The spatially resolved star formation law",

abstract = "We have studied the relationship between the star formation rate (SFR), surface density, and gas surface density in the spiral galaxy M51a (NGC 5194), using multiwavelength data obtained as part of the Spitzer Infrared Nearby Galaxies Survey (SINGS ). We introduce a new SFR index based on a linear combination of Ha emission-line and 24 µm continuum luminosities, which provides reliable extinction-corrected ionizing fluxes and SFR densities over a wide range of dust attenuations. The combination of these extinction-corrected SFR densities with aperture synthesis H I and CO maps has allowed us to probe the form of the spatially resolved star formation law on scales of 0.5-2 kpc. We find that the resolved SFR versus gas surface density relation is well represented by a Schmidt power law, which is similar in form and dispersion to the disk-averaged Schmidt law. We observe a comparably strong correlation of the SFR surface density with the molecular gas surface density, but no significant correlation with the surface density of atomic gas. The best-fitting slope of the Schmidt law varies from N = 1.37 to 1.56, with zero point and slope that change systematically with the spatial sampling scale. We tentatively attribute these variations to the effects of areal sampling and averaging of a nonlinear intrinsic star formation law. Our data can also be fitted by an alternative parameterization of the SFR surface density in terms of the ratio of gas surface density to local dynamical time, but with a considerable dispersion. {\textcopyright} 2007. The American Astronomical Society. All rights reserved.",

author = "Kennicutt, {R.C. C.} and D. Calzeti and F. Walter and G. Helou and Hollenbach, {D.J. J.} and L. Armus and G. Bendo and Dale, {D.A. A.} and Draine, {B.T. T.} and Engelbracht, {C.W. W.} and Gordon, {K.D. D.} and Prescott, {M.K.M. K.M.} and Regan, {M.W. W.} and Thornley, {M.D. D.} and C. Bot and E. Brinks and {De Blok}, E. and {De Mello}, D. and Martin Meyer and J. Moustakas and Murphy, {E.J. J.} and K. Sheth and Smith, {J.D.T. D.T.}",

year = "2007",

doi = "10.1086/522300",

language = "English",

volume = "671",

pages = "333--348",

journal = "The Astrophysical Journal",

issn = "0004-637X",

publisher = "IOP Publishing",

number = "1",

}

Kennicutt, RCC, Calzeti, D, Walter, F, Helou, G, Hollenbach, DJJ, Armus, L, Bendo, G, Dale, DAA, Draine, BTT, Engelbracht, CWW, Gordon, KDD, Prescott, MKMKM, Regan, MWW, Thornley, MDD, Bot, C, Brinks, E, De Blok, E, De Mello, D, Meyer, M, Moustakas, J, Murphy, EJJ, Sheth, K & Smith, JDTDT 2007, 'Star formation in NGC 5194 (M51a). II. The spatially resolved star formation law', The Astrophysical Journal, vol. 671, no. 1, pp. 333-348. https://doi.org/10.1086/522300

TY - JOUR

T1 - Star formation in NGC 5194 (M51a). II. The spatially resolved star formation law

AU - Kennicutt, R.C. C.

AU - Calzeti, D.

AU - Walter, F.

AU - Helou, G.

AU - Hollenbach, D.J. J.

AU - Armus, L.

AU - Bendo, G.

AU - Dale, D.A. A.

AU - Draine, B.T. T.

AU - Engelbracht, C.W. W.

AU - Gordon, K.D. D.

AU - Prescott, M.K.M. K.M.

AU - Regan, M.W. W.

AU - Thornley, M.D. D.

AU - Bot, C.

AU - Brinks, E.

AU - De Blok, E.

AU - De Mello, D.

AU - Meyer, Martin

AU - Moustakas, J.

AU - Murphy, E.J. J.

AU - Sheth, K.

AU - Smith, J.D.T. D.T.

PY - 2007

Y1 - 2007

N2 - We have studied the relationship between the star formation rate (SFR), surface density, and gas surface density in the spiral galaxy M51a (NGC 5194), using multiwavelength data obtained as part of the Spitzer Infrared Nearby Galaxies Survey (SINGS ). We introduce a new SFR index based on a linear combination of Ha emission-line and 24 µm continuum luminosities, which provides reliable extinction-corrected ionizing fluxes and SFR densities over a wide range of dust attenuations. The combination of these extinction-corrected SFR densities with aperture synthesis H I and CO maps has allowed us to probe the form of the spatially resolved star formation law on scales of 0.5-2 kpc. We find that the resolved SFR versus gas surface density relation is well represented by a Schmidt power law, which is similar in form and dispersion to the disk-averaged Schmidt law. We observe a comparably strong correlation of the SFR surface density with the molecular gas surface density, but no significant correlation with the surface density of atomic gas. The best-fitting slope of the Schmidt law varies from N = 1.37 to 1.56, with zero point and slope that change systematically with the spatial sampling scale. We tentatively attribute these variations to the effects of areal sampling and averaging of a nonlinear intrinsic star formation law. Our data can also be fitted by an alternative parameterization of the SFR surface density in terms of the ratio of gas surface density to local dynamical time, but with a considerable dispersion. © 2007. The American Astronomical Society. All rights reserved.

AB - We have studied the relationship between the star formation rate (SFR), surface density, and gas surface density in the spiral galaxy M51a (NGC 5194), using multiwavelength data obtained as part of the Spitzer Infrared Nearby Galaxies Survey (SINGS ). We introduce a new SFR index based on a linear combination of Ha emission-line and 24 µm continuum luminosities, which provides reliable extinction-corrected ionizing fluxes and SFR densities over a wide range of dust attenuations. The combination of these extinction-corrected SFR densities with aperture synthesis H I and CO maps has allowed us to probe the form of the spatially resolved star formation law on scales of 0.5-2 kpc. We find that the resolved SFR versus gas surface density relation is well represented by a Schmidt power law, which is similar in form and dispersion to the disk-averaged Schmidt law. We observe a comparably strong correlation of the SFR surface density with the molecular gas surface density, but no significant correlation with the surface density of atomic gas. The best-fitting slope of the Schmidt law varies from N = 1.37 to 1.56, with zero point and slope that change systematically with the spatial sampling scale. We tentatively attribute these variations to the effects of areal sampling and averaging of a nonlinear intrinsic star formation law. Our data can also be fitted by an alternative parameterization of the SFR surface density in terms of the ratio of gas surface density to local dynamical time, but with a considerable dispersion. © 2007. The American Astronomical Society. All rights reserved.

U2 - 10.1086/522300

DO - 10.1086/522300

M3 - Article

SN - 0004-637X

VL - 671

SP - 333

EP - 348

JO - The Astrophysical Journal

JF - The Astrophysical Journal

IS - 1

ER -

Star formation in NGC 5194 (M51a). II. The spatially resolved star formation law

Abstract

Access to Document

Fingerprint

Cite this