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The Luminosity Function of Early-Type Galaxies at z~0.75

N. J. G. Cross·R. Bouwens·N. Benitez·J. P. Blakeslee·F. Menanteau·H. C. Ford·T. Goto·B. Holden·A. R. Martel·R. Overzier·C. Gronwall·N. Homeier·D. R. Ardila·F. Bartko·T. J. Broadhurst·R. A. Brown·C. J. Burrows·E. S. Cheng·M. Clampin·P. D. Feldman·M. Franx·D. A. Golimowski·G. F. Hartig·G. D. Illingworth·L. Infante·R. A. Kimble·J. E. Krist·M. P. Lesser·G. R. Meurer·G. K. Miley·M. Postman·P. Rosati·M. Sirianni·W. B. Sparks·H. D. Tran·Z. I. Tsvetanov·R. L. White·W. Zheng
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Abstract

We measure the luminosity function of morphologically selected E/S0 galaxies from $z=0.5$ to $z=1.0$ using deep high resolution Advanced Camera for Surveys imaging data. Our analysis covers an area of $48\Box\arcmin$ (8$\times$ the area of the HDF-N) and extends 2 magnitudes deeper ($I\sim24$ mag) than was possible in the Deep Groth Strip Survey (DGSS). At $0.5 1.7$, E/S0 galaxies at brighter luminosities ($M_B<-20.1$), but are increasingly different at fainter magnitudes where `blue' galaxies are both smaller and have lower Sersic parameters. Fits of the colors to stellar population models suggest that most E/S0 galaxies have short star-formation time scales ($τ<1$ Gyr), and that galaxies have formed at an increasing rate from $z\sim8$ until $z\sim2$ after which there has been a gradual decline.

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N. J. G. Cross, R. Bouwens, N. Benitez, J. P. Blakeslee, F. Menanteau, H. C. Ford, T. Goto, B. Holden, A. R. Martel, R. Overzier, C. Gronwall, N. Homeier, D. R. Ardila, F. Bartko, T. J. Broadhurst, R. A. Brown, C. J. Burrows, E. S. Cheng, M. Clampin, P. D. Feldman, M. Franx, D. A. Golimowski, G. F. Hartig, G. D. Illingworth, L. Infante, R. A. Kimble, J. E. Krist, M. P. Lesser, G. R. Meurer, G. K. Miley, M. Postman, P. Rosati, M. Sirianni, W. B. Sparks, H. D. Tran, Z. I. Tsvetanov, R. L. White, W. Zheng. 2004-07-30. The Luminosity Function of Early-Type Galaxies at z~0.75. https://doi.org/10.1086/424857

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