Galaxy star formation as a function of environment in the early data release of the sloan digital sky survey

Percy L. Gómez, Robert C. Nichol, Christopher J. Miller, Michael L. Balogh, Tomotsugu Goto, Ann I Zabludoff, A. Kathy Romer, Mariangela Bernardi, Ravi Sheth, Andrew M. Hopkins, Francisco J. Castander, Andrew J. Connolly, Donald P. Schneider, Jon Brinkmann, Don Q. Lamb, Mark SubbaRao, Donald G. York

Research output: Contribution to journalArticle

542 Citations (Scopus)

Abstract

We present in this paper a detailed analysis of the effect of environment on the star formation activity of galaxies within the Early Data Release (EDR) of the Sloan Digital Sky Survey (SDSS). We have used the Ha emission line to derive the star formation rate (SFR) for each galaxy within a volume-limited sample of 8598 galaxies with 0.05 ≤ z ≤ 0.095 and M(r*} ≤ -20.45. We find that the SFR of galaxies is strongly correlated with the local (projected) galaxy density, and thus we present here a density-SFR relation that is analogous to the density-morphology relation. The effect of density on the SFR of galaxies is seen in three ways. First, the overall distribution of SFRs is shifted to lower values in dense environments compared with the. field population. Second, the effect is most noticeable for the strongly star-forming galaxies (Ha EW > 5 Å) in the 75th percentile of the SFR distribution. Third, there is a "break" (or characteristic density) in the density-SFR relation at a local galaxy density of ∼1 h75 -2 Mpc-2. To understand this break further, we have studied the SFR of galaxies as a function of clustercentric radius from 17 clusters and groups objectively selected from the SDSS EDR data. The distribution of SFRs of cluster galaxies begins to change, compared with the field population, at a clustercentric radius of 3-4 virial radii (at the >1 σ statistical significance), which is consistent with the characteristic break in density that we observe in the density-SFR relation. This effect with clustercentric radius is again most noticeable for the most strongly star-forming galaxies. Our tests suggest that the density-morphology relation alone is unlikely to explain the density-SFR relation we observe. For example, we have used the (inverse) concentration index of SDSS galaxies to classify late-type galaxies and show that the distribution of the star-forming (EW Hα > 5 Å) late-type galaxies is different in dense regions (within 2 virial radii) compared with similar galaxies in the field. However, at present, we are unable to make definitive statements about the independence of the density-morphology and density-SFR relation. We have tested our work against potential systematic uncertainties including stellar absorption, reddening, SDSS survey strategy, SDSS analysis pipelines, and aperture bias. Our observations are in qualitative agreement with recent simulations of hierarchical galaxy formation that predict a decrease in the SFR of galaxies within the virial radius. Our results are in agreement with recent 2dF Galaxy Redshift Survey results as well as consistent with previous observations of a decrease in the SFR of galaxies in the cores of distant clusters. Taken together, these works demonstrate that the decrease in SFR of galaxies in dense environments is a universal phenomenon over a wide range in density (from 0.08 to 10 h75-2 Mpc -2) and redshift (out to z ≃ 0.5).

Original languageEnglish (US)
Pages (from-to)210-227
Number of pages18
JournalAstrophysical Journal
Volume584
Issue number1 I
DOIs
StatePublished - Feb 10 2003

Fingerprint

star formation
star formation rate
galaxies
radii
rate
stars
galactic evolution

Keywords

  • Galaxies: clusters: general
  • Galaxies: evolution
  • Galaxies: stellar content stars: formation
  • Surveys

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Galaxy star formation as a function of environment in the early data release of the sloan digital sky survey. / Gómez, Percy L.; Nichol, Robert C.; Miller, Christopher J.; Balogh, Michael L.; Goto, Tomotsugu; Zabludoff, Ann I; Kathy Romer, A.; Bernardi, Mariangela; Sheth, Ravi; Hopkins, Andrew M.; Castander, Francisco J.; Connolly, Andrew J.; Schneider, Donald P.; Brinkmann, Jon; Lamb, Don Q.; SubbaRao, Mark; York, Donald G.

In: Astrophysical Journal, Vol. 584, No. 1 I, 10.02.2003, p. 210-227.

Research output: Contribution to journalArticle

Gómez, PL, Nichol, RC, Miller, CJ, Balogh, ML, Goto, T, Zabludoff, AI, Kathy Romer, A, Bernardi, M, Sheth, R, Hopkins, AM, Castander, FJ, Connolly, AJ, Schneider, DP, Brinkmann, J, Lamb, DQ, SubbaRao, M & York, DG 2003, 'Galaxy star formation as a function of environment in the early data release of the sloan digital sky survey', Astrophysical Journal, vol. 584, no. 1 I, pp. 210-227. https://doi.org/10.1086/345593
Gómez, Percy L. ; Nichol, Robert C. ; Miller, Christopher J. ; Balogh, Michael L. ; Goto, Tomotsugu ; Zabludoff, Ann I ; Kathy Romer, A. ; Bernardi, Mariangela ; Sheth, Ravi ; Hopkins, Andrew M. ; Castander, Francisco J. ; Connolly, Andrew J. ; Schneider, Donald P. ; Brinkmann, Jon ; Lamb, Don Q. ; SubbaRao, Mark ; York, Donald G. / Galaxy star formation as a function of environment in the early data release of the sloan digital sky survey. In: Astrophysical Journal. 2003 ; Vol. 584, No. 1 I. pp. 210-227.
@article{61d5332364524910ac5f9aa8e6805253,
title = "Galaxy star formation as a function of environment in the early data release of the sloan digital sky survey",
abstract = "We present in this paper a detailed analysis of the effect of environment on the star formation activity of galaxies within the Early Data Release (EDR) of the Sloan Digital Sky Survey (SDSS). We have used the Ha emission line to derive the star formation rate (SFR) for each galaxy within a volume-limited sample of 8598 galaxies with 0.05 ≤ z ≤ 0.095 and M(r*} ≤ -20.45. We find that the SFR of galaxies is strongly correlated with the local (projected) galaxy density, and thus we present here a density-SFR relation that is analogous to the density-morphology relation. The effect of density on the SFR of galaxies is seen in three ways. First, the overall distribution of SFRs is shifted to lower values in dense environments compared with the. field population. Second, the effect is most noticeable for the strongly star-forming galaxies (Ha EW > 5 {\AA}) in the 75th percentile of the SFR distribution. Third, there is a {"}break{"} (or characteristic density) in the density-SFR relation at a local galaxy density of ∼1 h75 -2 Mpc-2. To understand this break further, we have studied the SFR of galaxies as a function of clustercentric radius from 17 clusters and groups objectively selected from the SDSS EDR data. The distribution of SFRs of cluster galaxies begins to change, compared with the field population, at a clustercentric radius of 3-4 virial radii (at the >1 σ statistical significance), which is consistent with the characteristic break in density that we observe in the density-SFR relation. This effect with clustercentric radius is again most noticeable for the most strongly star-forming galaxies. Our tests suggest that the density-morphology relation alone is unlikely to explain the density-SFR relation we observe. For example, we have used the (inverse) concentration index of SDSS galaxies to classify late-type galaxies and show that the distribution of the star-forming (EW Hα > 5 {\AA}) late-type galaxies is different in dense regions (within 2 virial radii) compared with similar galaxies in the field. However, at present, we are unable to make definitive statements about the independence of the density-morphology and density-SFR relation. We have tested our work against potential systematic uncertainties including stellar absorption, reddening, SDSS survey strategy, SDSS analysis pipelines, and aperture bias. Our observations are in qualitative agreement with recent simulations of hierarchical galaxy formation that predict a decrease in the SFR of galaxies within the virial radius. Our results are in agreement with recent 2dF Galaxy Redshift Survey results as well as consistent with previous observations of a decrease in the SFR of galaxies in the cores of distant clusters. Taken together, these works demonstrate that the decrease in SFR of galaxies in dense environments is a universal phenomenon over a wide range in density (from 0.08 to 10 h75-2 Mpc -2) and redshift (out to z ≃ 0.5).",
keywords = "Galaxies: clusters: general, Galaxies: evolution, Galaxies: stellar content stars: formation, Surveys",
author = "G{\'o}mez, {Percy L.} and Nichol, {Robert C.} and Miller, {Christopher J.} and Balogh, {Michael L.} and Tomotsugu Goto and Zabludoff, {Ann I} and {Kathy Romer}, A. and Mariangela Bernardi and Ravi Sheth and Hopkins, {Andrew M.} and Castander, {Francisco J.} and Connolly, {Andrew J.} and Schneider, {Donald P.} and Jon Brinkmann and Lamb, {Don Q.} and Mark SubbaRao and York, {Donald G.}",
year = "2003",
month = "2",
day = "10",
doi = "10.1086/345593",
language = "English (US)",
volume = "584",
pages = "210--227",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "1 I",

}

TY - JOUR

T1 - Galaxy star formation as a function of environment in the early data release of the sloan digital sky survey

AU - Gómez, Percy L.

AU - Nichol, Robert C.

AU - Miller, Christopher J.

AU - Balogh, Michael L.

AU - Goto, Tomotsugu

AU - Zabludoff, Ann I

AU - Kathy Romer, A.

AU - Bernardi, Mariangela

AU - Sheth, Ravi

AU - Hopkins, Andrew M.

AU - Castander, Francisco J.

AU - Connolly, Andrew J.

AU - Schneider, Donald P.

AU - Brinkmann, Jon

AU - Lamb, Don Q.

AU - SubbaRao, Mark

AU - York, Donald G.

PY - 2003/2/10

Y1 - 2003/2/10

N2 - We present in this paper a detailed analysis of the effect of environment on the star formation activity of galaxies within the Early Data Release (EDR) of the Sloan Digital Sky Survey (SDSS). We have used the Ha emission line to derive the star formation rate (SFR) for each galaxy within a volume-limited sample of 8598 galaxies with 0.05 ≤ z ≤ 0.095 and M(r*} ≤ -20.45. We find that the SFR of galaxies is strongly correlated with the local (projected) galaxy density, and thus we present here a density-SFR relation that is analogous to the density-morphology relation. The effect of density on the SFR of galaxies is seen in three ways. First, the overall distribution of SFRs is shifted to lower values in dense environments compared with the. field population. Second, the effect is most noticeable for the strongly star-forming galaxies (Ha EW > 5 Å) in the 75th percentile of the SFR distribution. Third, there is a "break" (or characteristic density) in the density-SFR relation at a local galaxy density of ∼1 h75 -2 Mpc-2. To understand this break further, we have studied the SFR of galaxies as a function of clustercentric radius from 17 clusters and groups objectively selected from the SDSS EDR data. The distribution of SFRs of cluster galaxies begins to change, compared with the field population, at a clustercentric radius of 3-4 virial radii (at the >1 σ statistical significance), which is consistent with the characteristic break in density that we observe in the density-SFR relation. This effect with clustercentric radius is again most noticeable for the most strongly star-forming galaxies. Our tests suggest that the density-morphology relation alone is unlikely to explain the density-SFR relation we observe. For example, we have used the (inverse) concentration index of SDSS galaxies to classify late-type galaxies and show that the distribution of the star-forming (EW Hα > 5 Å) late-type galaxies is different in dense regions (within 2 virial radii) compared with similar galaxies in the field. However, at present, we are unable to make definitive statements about the independence of the density-morphology and density-SFR relation. We have tested our work against potential systematic uncertainties including stellar absorption, reddening, SDSS survey strategy, SDSS analysis pipelines, and aperture bias. Our observations are in qualitative agreement with recent simulations of hierarchical galaxy formation that predict a decrease in the SFR of galaxies within the virial radius. Our results are in agreement with recent 2dF Galaxy Redshift Survey results as well as consistent with previous observations of a decrease in the SFR of galaxies in the cores of distant clusters. Taken together, these works demonstrate that the decrease in SFR of galaxies in dense environments is a universal phenomenon over a wide range in density (from 0.08 to 10 h75-2 Mpc -2) and redshift (out to z ≃ 0.5).

AB - We present in this paper a detailed analysis of the effect of environment on the star formation activity of galaxies within the Early Data Release (EDR) of the Sloan Digital Sky Survey (SDSS). We have used the Ha emission line to derive the star formation rate (SFR) for each galaxy within a volume-limited sample of 8598 galaxies with 0.05 ≤ z ≤ 0.095 and M(r*} ≤ -20.45. We find that the SFR of galaxies is strongly correlated with the local (projected) galaxy density, and thus we present here a density-SFR relation that is analogous to the density-morphology relation. The effect of density on the SFR of galaxies is seen in three ways. First, the overall distribution of SFRs is shifted to lower values in dense environments compared with the. field population. Second, the effect is most noticeable for the strongly star-forming galaxies (Ha EW > 5 Å) in the 75th percentile of the SFR distribution. Third, there is a "break" (or characteristic density) in the density-SFR relation at a local galaxy density of ∼1 h75 -2 Mpc-2. To understand this break further, we have studied the SFR of galaxies as a function of clustercentric radius from 17 clusters and groups objectively selected from the SDSS EDR data. The distribution of SFRs of cluster galaxies begins to change, compared with the field population, at a clustercentric radius of 3-4 virial radii (at the >1 σ statistical significance), which is consistent with the characteristic break in density that we observe in the density-SFR relation. This effect with clustercentric radius is again most noticeable for the most strongly star-forming galaxies. Our tests suggest that the density-morphology relation alone is unlikely to explain the density-SFR relation we observe. For example, we have used the (inverse) concentration index of SDSS galaxies to classify late-type galaxies and show that the distribution of the star-forming (EW Hα > 5 Å) late-type galaxies is different in dense regions (within 2 virial radii) compared with similar galaxies in the field. However, at present, we are unable to make definitive statements about the independence of the density-morphology and density-SFR relation. We have tested our work against potential systematic uncertainties including stellar absorption, reddening, SDSS survey strategy, SDSS analysis pipelines, and aperture bias. Our observations are in qualitative agreement with recent simulations of hierarchical galaxy formation that predict a decrease in the SFR of galaxies within the virial radius. Our results are in agreement with recent 2dF Galaxy Redshift Survey results as well as consistent with previous observations of a decrease in the SFR of galaxies in the cores of distant clusters. Taken together, these works demonstrate that the decrease in SFR of galaxies in dense environments is a universal phenomenon over a wide range in density (from 0.08 to 10 h75-2 Mpc -2) and redshift (out to z ≃ 0.5).

KW - Galaxies: clusters: general

KW - Galaxies: evolution

KW - Galaxies: stellar content stars: formation

KW - Surveys

UR - http://www.scopus.com/inward/record.url?scp=0042552787&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0042552787&partnerID=8YFLogxK

U2 - 10.1086/345593

DO - 10.1086/345593

M3 - Article

AN - SCOPUS:0042552787

VL - 584

SP - 210

EP - 227

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 1 I

ER -