Hostname: page-component-76fb5796d-skm99 Total loading time: 0 Render date: 2024-04-26T06:13:41.871Z Has data issue: false hasContentIssue false
  • English
  • Français

The Fraction of Ionizing Photons Escaping from High-Redshift Galaxies

Published online by Cambridge University Press:  02 January 2013

Jhan A. Srbinovsky  and
J. Stuart B. Wyithe
Jhan A. Srbinovsky
Affiliation:
School of Physics, University of Melbourne, Parkville, Victoria, Australia
J. Stuart B. Wyithe*
Affiliation:
School of Physics, University of Melbourne, Parkville, Victoria, Australia
*
BCorresponding author. Email: swyithe@unimelb.edu.au
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The fraction (fesc) of ionizing photons that escape their host galaxy and so are able to ionize hydrogen in the intergalactic medium is a critical parameter in studies of the reionization era. In this paper we constrain fesc at high redshift by modelling the observed Lyα transmission. Using an N-body simulation of the cosmic web, we first model an ionizing background due to star-bursting galaxies. We then extract an ensemble of mock absorption spectra from the simulation and compute the mean transmission. We adjust the free parameter, fesc in our model of the ionizing background to reproduce the observed transmission. We find that fesc increases with the minimum galaxy mass considered to contribute to the ionizing background, and that at high redshift fesc must be greater than 5% irrespective of galaxy mass. Based on our numerical results we calibrate a semi-analytic model which shows that the ionizing background observed at z ∼ 5.5–6 implies a sufficient number of ionizing photons to have reionized the Universe by z ∼ 6. However, if the minimum mass for star-formation were ≳109 M⊙, the ionizing background would be over-produced at z ≲ 5. In summary, our results indicate that the Universe was reionized by low mass galaxies.

Keywords

cosmology: diffuse radiationgalaxies: high redshiftintergalactic mediumlarge scale structure of Universe
Type
Research Article
Information
Publications of the Astronomical Society of Australia , Volume 27 , Issue 1 , 2010 , pp. 110 - 123
Copyright
Copyright © Astronomical Society of Australia 2010

References

Alvarez, M. A., Bromm, V. & Shapiro, P. R., 2006, ApJ, 639, 621Google Scholar
Barkana, R. & Loeb, A., 2001, ApJS, 349, 125Google Scholar
Bergvall, N., Zackrisson, E., Andersson, B.-G., Arnberg, D., Masegosa, J. & Östlin, G., 2006, A&A, 448, 513Google Scholar
Bland-Hawthorn, J. & Maloney, P. R., 1999, ApJ, 510, L33CrossRefGoogle Scholar
Bolton, J. S. & Haehnelt, M. G., 2007, MNRAS, 382, 325CrossRefGoogle Scholar
Bolton, J. S., Haehnelt, M. G., Viel, M. & Springel, V., 2005, MNRAS, 357, 1178CrossRefGoogle Scholar
Bond, J.R., Cole, S., Efstathiou, G. & Kaiser, N., 1991, ApJ, 379, 440Google Scholar
Bouwens, R. J., Illingworth, G. D., Franx, M. & Ford, H., 2007, ApJ, 670, 928Google Scholar
Chen, H.-W., Prochaska, J. X. & Gnedin, N. Y., 2007, ApJ, 667, L125CrossRefGoogle Scholar
Choudhury, T. R. & Ferrara, A., 2005, MNRAS, 361, 577CrossRefGoogle Scholar
Ciardi, B., Bianchi, S. & Ferrara, A., 2002, MNRAS, 331, 463CrossRefGoogle Scholar
Clarke, C. & Oey, M. S., 2002, MNRAS, 337, 1299Google Scholar
Croft, R. A. C., 2004, ApJ, 610, 642Google Scholar
Deharveng, J.-M., Buat, V., Le Brun, V., Milliard, B., Kunth, D., Shull, J. M. & Gry, C., 2001, A&A, 375, 805Google Scholar
Dijkstra, M., Haiman, Z., Rees, M. J. & Weinberg, D. H., 2004, ApJ, 601, 666CrossRefGoogle Scholar
Dove, J. B. & Shull, J. M., 1994, ApJ, 430, 222Google Scholar
Dove, J. B., Shull, J. M. & Ferrara, A., 2000, ApJ, 531, 846CrossRefGoogle Scholar
Efstathiou, G., 1992, MNRAS, 256, 43CrossRefGoogle Scholar
Fan, X., Narayanan, V. K., Strauss, M. A., White, R. L., Becker, R. H., Pentericci, L. & Rix, H. W., 2002, AJ, 123, 1247CrossRefGoogle Scholar
Fan, X. et al. , 2006, AJ, 132, 117Google Scholar
Faucher-Giguere, C., Lidz, A., Hernquist, L., Zaldarriaga, M. & 2008, ApJ, 688, 85Google Scholar
Fernández-Soto, A., Lanzetta, K.M. & Chen, H.-W., 2003, MNRAS, 342, 1215Google Scholar
Fujita, A., Martin, C. L., Mac Low, M.-M. & Abel, T., 2003, ApJ, 599, 50CrossRefGoogle Scholar
Furlanetto, S. R. & Oh, S. P., 2005, MNRAS, 363, 1031Google Scholar
Giallongo, E., Cristiani, S., D'Odorico, S. & Fontana, A., 2002, ApJ, 568, L9CrossRefGoogle Scholar
Gnedin, N.Y., 2008, ApJL, 673, L1Google Scholar
Gnedin, N.Y. & Hamilton, A. J. S., 2002, MNRAS, 334, 107Google Scholar
Gnedin, N.Y. & Hui, L., 1998, MNRAS, 296, 44Google Scholar
Gnedin, N.Y., Kravtsov, A. V. & Chen, H.-W., 2008, ApJ, 672, 765CrossRefGoogle Scholar
Grimes, J. P. et al. , 2007, ApJ, 668, 891CrossRefGoogle Scholar
Heckman, T. M., Sembach, K. R., Meurer, G. R., Leitherer, C., Calzetti, D. & Martin, C. L., 2001, ApJ, 558, 56CrossRefGoogle Scholar
Hui, L., Gnedin, N.Y. & Zhang, Y., 1997, ApJ, 486, 599CrossRefGoogle Scholar
Hurwitz, M., Jelinsky, P. & Dixon, W. V. D., 1997, ApJ, 481, L31CrossRefGoogle Scholar
Inoue, A. K., Iwata, I. & Deharveng, J.-M., 2006, MNRAS, 371, L1Google Scholar
Inoue, A. K., Iwata, I., Deharveng, J.-M., Buat, V. & Burgarella, D., 2005, A&A, 435, 471Google Scholar
Kitayama, T., Yoshida, N., Susa, H. & Umemura, M., 2004, ApJ, 613, 631Google Scholar
Komatsu, E. et al. , 2009, ApJS, 180, 330CrossRefGoogle Scholar
Lai, K., Lidz, A., Hernquist, L. & Zaldarriaga, M., 2006, ApJ, 644, 61Google Scholar
Leitherer, C. et al. , 1999, ApJS, 123, 3CrossRefGoogle Scholar
Lidz, A., Oh, S. P. & Furlanetto, S. R., 2006, ApJ, 639, L47CrossRefGoogle Scholar
Lidz, A., Zahn, O., McQuinn, M., Zaldarriaga, M., Dutta, S. Hernquist, L., 2007, ApJ, 659, 865Google Scholar
Loeb, A., Barkana, R. & Hernquist, L., 2005, ApJ, 620, 553Google Scholar
Madau, P., Haardt, F. & Rees, M. J., 1999, ApJ, 514, 648CrossRefGoogle Scholar
Malkan, M., Webb, W. & Konopacky, Q., 2003, ApJ, 598, 878CrossRefGoogle Scholar
McDonald, P., Seljak, U., Cen, R., Bode, P. & Ostriker, J. P., 2005, MNRAS, 360, 1471Google Scholar
McQuinn, M., Lidz, A., Zahn, O., Dutta, S., Hernquist, L. & Zaldarriaga, M., 2007, MNRAS, 377, 1043Google Scholar
Meiksin, A. & White, M., 2004, MNRAS, 350, 1107Google Scholar
Miralda-Escudé, J., 2003, ApJ, 597, 66Google Scholar
Miralda-Escudé, J., Haehnelt, M. & Rees, M. J., 2000, ApJ, 530, 1CrossRefGoogle Scholar
Press, W. H. & Schechter, P., 1974, ApJ, 187, 425CrossRefGoogle Scholar
Prochaska, J. X., Herbert-Fort, S. & Wolfe, A. M., 2005, ApJ, 635, 123Google Scholar
Razoumov, A. O. & Sommer-Larsen, J., 2006, ApJ, 651, L89CrossRefGoogle Scholar
Scalo, J., 1998, ASPC, 142, 201Google Scholar
Scannapieco, E., Schneider, R. & Ferrara, A., 2003, ApJ, 589, 35Google Scholar
Schaye, J., 2006, ApJ, 643, 59CrossRefGoogle Scholar
Schaye, J., Aguirre, A., Kim, T.-S., Theuns, T., Rauch, M. & Sargent, W. L. W., 2003, ApJ, 596, 768Google Scholar
Schneider, R., Salvaterra, R., Ferrara, A. & Ciardi, B., 2006, MNRAS, 369, 825CrossRefGoogle Scholar
Shapley, A. E., Steidel, C. C., Pettini, M., Adelberger, K. L. & Erb, D. K., 2006, ApJ, 651, 688Google Scholar
Sheth, R. K. Tormen, G., 1999, MNRAS, 308, 119Google Scholar
Siana, B. et al. , 2007, ApJ, 668, 62Google Scholar
Songaila, A., 2004, AJ, 127, 2598CrossRefGoogle Scholar
Srbinovsky, J. A. & Wyithe, J. S. B., 2007, MNRAS, 374, 627Google Scholar
Steidel, C. C., Pettini, M. & Adelberger, K. L., 2001, ApJ, 546, 665Google Scholar
Storrie-Lombardi, L. J., McMahon, R. G., Irwin, M. J. & Hazard, C., 1994, ApJ, 427, L13Google Scholar
Thoul, A. A. & Weinberg, D. H., 1996, ApJ, 465, 608CrossRefGoogle Scholar
Whalen, D., Abel, T. & Norman, M. L., 2004, ApJ, 610, 14Google Scholar
Wood, K. & Loeb, A., 2000, ApJ, 545, 86Google Scholar
Wyithe, J. S. B. & Cen, R., 2007, ApJ, 659, 890Google Scholar
Wyithe, J. S. B. & Loeb, A., 2003, ApJ, 586, 693Google Scholar
Wyithe, S., Bolton, J. & Haehnelt, M., 2007, ArXiv e-prints, 708Google Scholar
Zahn, O., Lidz, A., McQuinn, M., Dutta, S., Hernquist, L., Zaldarriaga, M. & Furlanetto, S. R., 2007, ApJ, 654, 12Google Scholar