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The Hα luminosity function and star formation rate at z ≈ 0.24 in the COSMOS 2 square degree field

Shioya, Y. and Taniguchi, Y. and Sasaki, S. S. and Nagao, T. and Murayama, T. and Takahashi, M. I. and Ajiki, M. and Ideue, Y. and Mihara, S. and Nakajima, A. and Scoville, N. Z. and Mobasher, B. and Aussel, H. and Giavalisco, M. and Guzzo, L. and Hasinger, G. and Impey, C. and Le Fèvre, O. and Lilly, S. and Renzini, A. and Rich, M. and Sanders, D. B. and Schinnerer, E. and Shopbell, P. and Leauthaud, A. and Kneib, J. P. and Rhodes, J. and Massey, R. (2008) The Hα luminosity function and star formation rate at z ≈ 0.24 in the COSMOS 2 square degree field. Astrophysical Journal Supplement Series, 175 (3). pp. 128-137. ISSN 0067-0049.

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To derive a new Hα luminosity function and to understand the clustering properties of star-forming galaxies at z≈ 0.24, we have made a narrowband imaging survey for Hα-emitting galaxies in the Hubble Space Telescope (HST) COSMOS 2 square degree field. We used the narrowband filter NB816 (λ_c = 8150 Å, Δ λ = 120 Å) and sampled Hα emitters with EW_(obs)(H α + [N II]) > 12Å in a redshift range between z = 0.233 and 0.251 corresponding to a depth of 70 Mpc. We obtained 980 Hα-emitting galaxies in a sky area of 5540 arcmin^2, corresponding to a survey volume of 3.1 × 10^4 Mpc^3. We derive a Hα luminosity function with a best-fit Schechter function parameter set of α = − 1.35_(−0.13)^(+0.11), log ф_* = − 2.65_(−0.38)^(+0.27), and log L_*(ergs s^(−1)) = 41.94_(−0.23)^(+0.38). The Hα luminosity density is 2.7_(−0.6)^(+0.7) × 10^(39) ergs s^(−1) Mpc^(−3). After subtracting the AGN contribution (15%) to the Hα luminosity density, the star formation rate density is evaluated as 1.8_(−0.4)^(+0.7) × 10^(−2) M_סּ yr^(−1) Mpc^(−3). The angular two-point correlation function of Hα-emitting galaxies of log L(H α) > 39.8 is well fit by a power-law form of w(θ) = 0.013−_(0.001)^(+0.002)θ^(−0.88 ± 0.03), corresponding to the correlation function of ξ (r) = (r/1.9 Mpc)^(−1.88). We also find that the Hα emitters with higher Hα luminosity are more strongly clustered than those with lower luminosity.

Item Type:Article
Related URLs:
URLURL TypeDescription
Taniguchi, Y.0000-0003-2247-3741
Nagao, T.0000-0002-7402-5441
Scoville, N. Z.0000-0002-0438-3323
Aussel, H.0000-0002-1371-5705
Giavalisco, M.0000-0002-7831-8751
Hasinger, G.0000-0002-0797-0646
Le Fèvre, O.0000-0001-5891-2596
Lilly, S.0000-0002-6423-3597
Renzini, A.0000-0002-7093-7355
Sanders, D. B.0000-0002-1233-9998
Schinnerer, E.0000-0002-3933-7677
Leauthaud, A.0000-0002-3677-3617
Kneib, J. P.0000-0002-4616-4989
Rhodes, J.0000-0002-4485-8549
Massey, R.0000-0002-6085-3780
Additional Information:© 2008. The American Astronomical Society. Received 2006 September 10; accepted 2007 September 5. The HST COSMOS Treasury program was supported through NASA grant HST-GO-09822.We greatly acknowledge the contributions of the entire COSMOS collaboration consisting of more than 70 scientists. The COSMOS science meeting in 2005 May was supported by in part by the NSF through grant OISE-0456439.We would also like to thank the Subaru Telescope staff for their invaluable help. This work was financially supported in part by the JSPS (nos. 15340059 and 17253001). S. S. S. and T. N. are JSPS fellows.
Group:Infrared Processing and Analysis Center (IPAC)
Funding AgencyGrant Number
Japan Society for the Promotion of Science (JSPS)15340059
Japan Society for the Promotion of Science (JSPS)17253001
Subject Keywords:galaxies: distances and redshifts; galaxies: evolution; galaxies: luminosity function; mass function
Issue or Number:3
Record Number:CaltechAUTHORS:20090608-114235177
Persistent URL:
Official Citation:The Hα Luminosity Function and Star Formation Rate at z 0.24 in the COSMOS 2 Square Degree Field Y. Shioya, Y. Taniguchi, S. S. Sasaki, T. Nagao, T. Murayama, M. I. Takahashi, M. Ajiki, Y. Ideue, S. Mihara, A. Nakajima, N. Z. Scoville, B. Mobasher, H. Aussel, M. Giavalisco, L. Guzzo, G. Hasinger, C. Impey, O. Le Fèvre, S. Lilly, A. Renzini, M. Rich, D. B. Sanders, E. Schinnerer, P. Shopbell, A. Leauthaud, J.-P. Kneib, J. Rhodes, and R. Massey 2008 ApJS 175 128-137 doi: 10.1086/523703
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:14372
Deposited By: Ruth Sustaita
Deposited On:28 Aug 2009 23:31
Last Modified:09 Mar 2020 13:19

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