The Lyα Properties of faint galaxies at z ∼ 2-3 with systemic redshifts and velocity dispersions from keck-mosfire

Dawn K. Erb, Charles C. Steidel, Ryan F. Trainor, Milan Bogosavljevic, Alice E. Shapley, Daniel B. Nestor, Kristin R. Kulas, David R. Law, Allison L. Strom, Gwen C. Rudie, Naveen A. Reddy, Max Pettini, Nicholas P. Konidaris, Gregory Mace, Keith Matthews, Ian S. McLean

    Research output: Contribution to journalArticle

    Abstract

    We study the Lyα profiles of 36 spectroscopically detected Lyα-emitters (LAEs) at z ∼ 2-3, using Keck MOSFIRE to measure systemic redshifts and velocity dispersions from rest-frame optical nebular emission lines. The sample has a median optical magnitude , and ranges from to , corresponding to rest-frame UV absolute magnitudes M UV ≃ -22 to M UV > -18.2. Dynamical masses range from M dyn < 1.3 × 108 M to M dyn = 6.8 × 109 M, with a median value of M dyn = 6.3 × 108 M. Thirty of the 36 Lyα emission lines are redshifted with respect to the systemic velocity with at least 1σ significance, and the velocity offset with respect to systemic Δv Lyα is correlated with the -band magnitude, M UV, and the velocity dispersion measured from nebular emission lines with >3σ significance: brighter galaxies with larger velocity dispersions tend to have larger values of Δv Lyα. We also make use of a comparison sample of 122 UV-color-selected galaxies at z ∼ 2, all with Lyα emission and systemic redshifts measured from nebular emission lines. Using the combined LAE and comparison samples for a total of 158 individual galaxies, we find that Δv Lyα is anti-correlated with the Lyα equivalent width with 7σ significance. Our results are consistent with a scenario in which the Lyα profile is determined primarily by the properties of the gas near the systemic redshift; in such a scenario, the opacity to Lyα photons in lower mass galaxies may be reduced if large gaseous disks have not yet developed and if the gas is ionized by the harder spectrum of young, low metallicity stars.

    Original languageEnglish (US)
    Article number33
    JournalAstrophysical Journal
    Volume795
    Issue number1
    DOIs
    StatePublished - Nov 1 2014

    Fingerprint

    galaxies
    gas
    ionized gases
    profiles
    opacity
    metallicity
    light emission
    emitters
    color
    stars
    photons
    gases
    comparison
    young

    Keywords

    • galaxies: evolution
    • galaxies: formation
    • galaxies: high-redshift

    ASJC Scopus subject areas

    • Astronomy and Astrophysics
    • Space and Planetary Science

    Cite this

    Erb, D. K., Steidel, C. C., Trainor, R. F., Bogosavljevic, M., Shapley, A. E., Nestor, D. B., ... McLean, I. S. (2014). The Lyα Properties of faint galaxies at z ∼ 2-3 with systemic redshifts and velocity dispersions from keck-mosfire. Astrophysical Journal, 795(1), [33]. https://doi.org/10.1088/0004-637X/795/1/33

    The Lyα Properties of faint galaxies at z ∼ 2-3 with systemic redshifts and velocity dispersions from keck-mosfire. / Erb, Dawn K.; Steidel, Charles C.; Trainor, Ryan F.; Bogosavljevic, Milan; Shapley, Alice E.; Nestor, Daniel B.; Kulas, Kristin R.; Law, David R.; Strom, Allison L.; Rudie, Gwen C.; Reddy, Naveen A.; Pettini, Max; Konidaris, Nicholas P.; Mace, Gregory; Matthews, Keith; McLean, Ian S.

    In: Astrophysical Journal, Vol. 795, No. 1, 33, 01.11.2014.

    Research output: Contribution to journalArticle

    Erb, DK, Steidel, CC, Trainor, RF, Bogosavljevic, M, Shapley, AE, Nestor, DB, Kulas, KR, Law, DR, Strom, AL, Rudie, GC, Reddy, NA, Pettini, M, Konidaris, NP, Mace, G, Matthews, K & McLean, IS 2014, 'The Lyα Properties of faint galaxies at z ∼ 2-3 with systemic redshifts and velocity dispersions from keck-mosfire', Astrophysical Journal, vol. 795, no. 1, 33. https://doi.org/10.1088/0004-637X/795/1/33
    Erb, Dawn K. ; Steidel, Charles C. ; Trainor, Ryan F. ; Bogosavljevic, Milan ; Shapley, Alice E. ; Nestor, Daniel B. ; Kulas, Kristin R. ; Law, David R. ; Strom, Allison L. ; Rudie, Gwen C. ; Reddy, Naveen A. ; Pettini, Max ; Konidaris, Nicholas P. ; Mace, Gregory ; Matthews, Keith ; McLean, Ian S. / The Lyα Properties of faint galaxies at z ∼ 2-3 with systemic redshifts and velocity dispersions from keck-mosfire. In: Astrophysical Journal. 2014 ; Vol. 795, No. 1.
    @article{05dc6ba529cb4ccdad411bada7048ae0,
    title = "The Lyα Properties of faint galaxies at z ∼ 2-3 with systemic redshifts and velocity dispersions from keck-mosfire",
    abstract = "We study the Lyα profiles of 36 spectroscopically detected Lyα-emitters (LAEs) at z ∼ 2-3, using Keck MOSFIRE to measure systemic redshifts and velocity dispersions from rest-frame optical nebular emission lines. The sample has a median optical magnitude , and ranges from to , corresponding to rest-frame UV absolute magnitudes M UV ≃ -22 to M UV > -18.2. Dynamical masses range from M dyn < 1.3 × 108 M to M dyn = 6.8 × 109 M, with a median value of M dyn = 6.3 × 108 M. Thirty of the 36 Lyα emission lines are redshifted with respect to the systemic velocity with at least 1σ significance, and the velocity offset with respect to systemic Δv Lyα is correlated with the -band magnitude, M UV, and the velocity dispersion measured from nebular emission lines with >3σ significance: brighter galaxies with larger velocity dispersions tend to have larger values of Δv Lyα. We also make use of a comparison sample of 122 UV-color-selected galaxies at z ∼ 2, all with Lyα emission and systemic redshifts measured from nebular emission lines. Using the combined LAE and comparison samples for a total of 158 individual galaxies, we find that Δv Lyα is anti-correlated with the Lyα equivalent width with 7σ significance. Our results are consistent with a scenario in which the Lyα profile is determined primarily by the properties of the gas near the systemic redshift; in such a scenario, the opacity to Lyα photons in lower mass galaxies may be reduced if large gaseous disks have not yet developed and if the gas is ionized by the harder spectrum of young, low metallicity stars.",
    keywords = "galaxies: evolution, galaxies: formation, galaxies: high-redshift",
    author = "Erb, {Dawn K.} and Steidel, {Charles C.} and Trainor, {Ryan F.} and Milan Bogosavljevic and Shapley, {Alice E.} and Nestor, {Daniel B.} and Kulas, {Kristin R.} and Law, {David R.} and Strom, {Allison L.} and Rudie, {Gwen C.} and Reddy, {Naveen A.} and Max Pettini and Konidaris, {Nicholas P.} and Gregory Mace and Keith Matthews and McLean, {Ian S.}",
    year = "2014",
    month = "11",
    day = "1",
    doi = "10.1088/0004-637X/795/1/33",
    language = "English (US)",
    volume = "795",
    journal = "Astrophysical Journal",
    issn = "0004-637X",
    publisher = "IOP Publishing Ltd.",
    number = "1",

    }

    TY - JOUR

    T1 - The Lyα Properties of faint galaxies at z ∼ 2-3 with systemic redshifts and velocity dispersions from keck-mosfire

    AU - Erb, Dawn K.

    AU - Steidel, Charles C.

    AU - Trainor, Ryan F.

    AU - Bogosavljevic, Milan

    AU - Shapley, Alice E.

    AU - Nestor, Daniel B.

    AU - Kulas, Kristin R.

    AU - Law, David R.

    AU - Strom, Allison L.

    AU - Rudie, Gwen C.

    AU - Reddy, Naveen A.

    AU - Pettini, Max

    AU - Konidaris, Nicholas P.

    AU - Mace, Gregory

    AU - Matthews, Keith

    AU - McLean, Ian S.

    PY - 2014/11/1

    Y1 - 2014/11/1

    N2 - We study the Lyα profiles of 36 spectroscopically detected Lyα-emitters (LAEs) at z ∼ 2-3, using Keck MOSFIRE to measure systemic redshifts and velocity dispersions from rest-frame optical nebular emission lines. The sample has a median optical magnitude , and ranges from to , corresponding to rest-frame UV absolute magnitudes M UV ≃ -22 to M UV > -18.2. Dynamical masses range from M dyn < 1.3 × 108 M to M dyn = 6.8 × 109 M, with a median value of M dyn = 6.3 × 108 M. Thirty of the 36 Lyα emission lines are redshifted with respect to the systemic velocity with at least 1σ significance, and the velocity offset with respect to systemic Δv Lyα is correlated with the -band magnitude, M UV, and the velocity dispersion measured from nebular emission lines with >3σ significance: brighter galaxies with larger velocity dispersions tend to have larger values of Δv Lyα. We also make use of a comparison sample of 122 UV-color-selected galaxies at z ∼ 2, all with Lyα emission and systemic redshifts measured from nebular emission lines. Using the combined LAE and comparison samples for a total of 158 individual galaxies, we find that Δv Lyα is anti-correlated with the Lyα equivalent width with 7σ significance. Our results are consistent with a scenario in which the Lyα profile is determined primarily by the properties of the gas near the systemic redshift; in such a scenario, the opacity to Lyα photons in lower mass galaxies may be reduced if large gaseous disks have not yet developed and if the gas is ionized by the harder spectrum of young, low metallicity stars.

    AB - We study the Lyα profiles of 36 spectroscopically detected Lyα-emitters (LAEs) at z ∼ 2-3, using Keck MOSFIRE to measure systemic redshifts and velocity dispersions from rest-frame optical nebular emission lines. The sample has a median optical magnitude , and ranges from to , corresponding to rest-frame UV absolute magnitudes M UV ≃ -22 to M UV > -18.2. Dynamical masses range from M dyn < 1.3 × 108 M to M dyn = 6.8 × 109 M, with a median value of M dyn = 6.3 × 108 M. Thirty of the 36 Lyα emission lines are redshifted with respect to the systemic velocity with at least 1σ significance, and the velocity offset with respect to systemic Δv Lyα is correlated with the -band magnitude, M UV, and the velocity dispersion measured from nebular emission lines with >3σ significance: brighter galaxies with larger velocity dispersions tend to have larger values of Δv Lyα. We also make use of a comparison sample of 122 UV-color-selected galaxies at z ∼ 2, all with Lyα emission and systemic redshifts measured from nebular emission lines. Using the combined LAE and comparison samples for a total of 158 individual galaxies, we find that Δv Lyα is anti-correlated with the Lyα equivalent width with 7σ significance. Our results are consistent with a scenario in which the Lyα profile is determined primarily by the properties of the gas near the systemic redshift; in such a scenario, the opacity to Lyα photons in lower mass galaxies may be reduced if large gaseous disks have not yet developed and if the gas is ionized by the harder spectrum of young, low metallicity stars.

    KW - galaxies: evolution

    KW - galaxies: formation

    KW - galaxies: high-redshift

    UR - http://www.scopus.com/inward/record.url?scp=84908031930&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=84908031930&partnerID=8YFLogxK

    U2 - 10.1088/0004-637X/795/1/33

    DO - 10.1088/0004-637X/795/1/33

    M3 - Article

    VL - 795

    JO - Astrophysical Journal

    JF - Astrophysical Journal

    SN - 0004-637X

    IS - 1

    M1 - 33

    ER -