Quasar Elemental Abundances at High Redshifts

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Standard

Quasar Elemental Abundances at High Redshifts. / Dietrich, M.; Hamann, F.; Shields, J. C.; Constantin, A.; Heidt, J.; Jaeger, K.; Vestergaard, Marianne; Wagner, S. J.

I: Astrophysical Journal, Bind 589, Nr. 2, 722, 24.02.2003.

Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › fagfællebedømt

Harvard

Dietrich, M, Hamann, F, Shields, JC, Constantin, A, Heidt, J, Jaeger, K, Vestergaard, M & Wagner, SJ 2003, 'Quasar Elemental Abundances at High Redshifts', Astrophysical Journal, bind 589, nr. 2, 722. https://doi.org/10.1086/374662

APA

Dietrich, M., Hamann, F., Shields, J. C., Constantin, A., Heidt, J., Jaeger, K., Vestergaard, M., & Wagner, S. J. (2003). Quasar Elemental Abundances at High Redshifts. Astrophysical Journal, 589(2), [722]. https://doi.org/10.1086/374662

Vancouver

Dietrich M, Hamann F, Shields JC, Constantin A, Heidt J, Jaeger K o.a. Quasar Elemental Abundances at High Redshifts. Astrophysical Journal. 2003 feb. 24;589(2). 722. https://doi.org/10.1086/374662

Author

Dietrich, M. ; Hamann, F. ; Shields, J. C. ; Constantin, A. ; Heidt, J. ; Jaeger, K. ; Vestergaard, Marianne ; Wagner, S. J. / Quasar Elemental Abundances at High Redshifts. I: Astrophysical Journal. 2003 ; Bind 589, Nr. 2.

Bibtex

@article{affba518eba140ac9046e8febcac5313,
title = "Quasar Elemental Abundances at High Redshifts",
abstract = "We examine rest-frame ultraviolet spectra of 70 high redshift quasars (z>3.5) to study the chemical enrichment history of the gas closely related to the quasars, and thereby estimate the epoch of first star formation. The fluxes of several ultraviolet emission lines were investigated within the framework of the most recent photoionization models to estimate the metallicity of the gas associated with the high-z quasars. Standard photoionization parameters and the assumption of secondary nitrogen enrichment indicate an average abundance of Z/Z_sol = 4 to 5 in the line emitting gas. Assuming a time scale of t_evol = 0.5 - 0.8 Gyrs for the chemical enrichment of the gas, the first major star formation for quasars with z>=4 should have started at a redshift of z_f = 6 - 8, corresponding to an age of the universe of several 10^8 yrs (H_o = 65 km/s/Mpc, Omega_M = 0.3, Omega_Lambda = 0.7). We note that this also appears to be the era of re-ionization of the universe. Finally, there is some evidence for a positive luminosity - metallicity relation in this high redshift quasar sample.",
keywords = "astro-ph",
author = "M. Dietrich and F. Hamann and Shields, {J. C.} and A. Constantin and J. Heidt and K. Jaeger and Marianne Vestergaard and Wagner, {S. J.}",
year = "2003",
month = feb,
day = "24",
doi = "10.1086/374662",
language = "English",
volume = "589",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "Institute of Physics Publishing, Inc",
number = "2",

}

RIS

TY - JOUR

T1 - Quasar Elemental Abundances at High Redshifts

AU - Dietrich, M.

AU - Hamann, F.

AU - Shields, J. C.

AU - Constantin, A.

AU - Heidt, J.

AU - Jaeger, K.

AU - Vestergaard, Marianne

AU - Wagner, S. J.

PY - 2003/2/24

Y1 - 2003/2/24

N2 - We examine rest-frame ultraviolet spectra of 70 high redshift quasars (z>3.5) to study the chemical enrichment history of the gas closely related to the quasars, and thereby estimate the epoch of first star formation. The fluxes of several ultraviolet emission lines were investigated within the framework of the most recent photoionization models to estimate the metallicity of the gas associated with the high-z quasars. Standard photoionization parameters and the assumption of secondary nitrogen enrichment indicate an average abundance of Z/Z_sol = 4 to 5 in the line emitting gas. Assuming a time scale of t_evol = 0.5 - 0.8 Gyrs for the chemical enrichment of the gas, the first major star formation for quasars with z>=4 should have started at a redshift of z_f = 6 - 8, corresponding to an age of the universe of several 10^8 yrs (H_o = 65 km/s/Mpc, Omega_M = 0.3, Omega_Lambda = 0.7). We note that this also appears to be the era of re-ionization of the universe. Finally, there is some evidence for a positive luminosity - metallicity relation in this high redshift quasar sample.

AB - We examine rest-frame ultraviolet spectra of 70 high redshift quasars (z>3.5) to study the chemical enrichment history of the gas closely related to the quasars, and thereby estimate the epoch of first star formation. The fluxes of several ultraviolet emission lines were investigated within the framework of the most recent photoionization models to estimate the metallicity of the gas associated with the high-z quasars. Standard photoionization parameters and the assumption of secondary nitrogen enrichment indicate an average abundance of Z/Z_sol = 4 to 5 in the line emitting gas. Assuming a time scale of t_evol = 0.5 - 0.8 Gyrs for the chemical enrichment of the gas, the first major star formation for quasars with z>=4 should have started at a redshift of z_f = 6 - 8, corresponding to an age of the universe of several 10^8 yrs (H_o = 65 km/s/Mpc, Omega_M = 0.3, Omega_Lambda = 0.7). We note that this also appears to be the era of re-ionization of the universe. Finally, there is some evidence for a positive luminosity - metallicity relation in this high redshift quasar sample.

KW - astro-ph

U2 - 10.1086/374662

DO - 10.1086/374662

M3 - Journal article

VL - 589

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 2

M1 - 722

ER -

ID: 123370915