| Autor: |
Ilbert, O., Capak, P., Salvato, M., Aussel, H., McCracken, H. J., Sanders, D. B., Scoville, N., Kartaltepe, J., Arnouts, S., Floc'h, E. Le, Mobasher, B., Taniguchi, Y., Lamareille, F., Leauthaud, A., Sasaki, S., Thompson, D., Zamojski, M., Zamorani, G., Bardelli, S., Bolzonella, M., Bongiorno, A., Brusa, M., Caputi, K. I., Carollo, C. M., Contini, T., Cook, R., Coppa, G., Cucciati, O., de la Torre, S., de Ravel, L., Franzetti, P., Garilli, B., Hasinger, G., Iovino, A., Kampczyk, P., Kneib, J. -P., Knobel, C., Kovac, K., Borgne, J. F. Le, Brun, V. Le, Fevre, O. Le, Lilly, S., Looper, D., Maier, C., Mainieri, V., Mellier, Y., Mignoli, M., Murayama, T., Pello, R., Peng, Y., Perez-Montero, E., Renzini, A., Ricciardelli, E., Schiminovich, D., Scodeggio, M., Shioya, Y., Silverman, J., Surace, J., Tanaka, M., Tasca, L., Tresse, L., Vergani, D., Zucca, E. |
| Rok vydání: |
2008 |
| Předmět: |
|
| Zdroj: |
Astrophys.J.690:1236-1249,2009 |
| Druh dokumentu: |
Working Paper |
| DOI: |
10.1088/0004-637X/690/2/1236 |
| Popis: |
We present accurate photometric redshifts in the 2-deg2 COSMOS field. The redshifts are computed with 30 broad, intermediate, and narrow bands covering the UV (GALEX), Visible-NIR (Subaru, CFHT, UKIRT and NOAO) and mid-IR (Spitzer/IRAC). A chi2 template-fitting method (Le Phare) was used and calibrated with large spectroscopic samples from VLT-VIMOS and Keck-DEIMOS. We develop and implement a new method which accounts for the contributions from emission lines (OII, Hbeta, Halpha and Ly) to the spectral energy distributions (SEDs). The treatment of emission lines improves the photo-z accuracy by a factor of 2.5. Comparison of the derived photo-z with 4148 spectroscopic redshifts (i.e. Delta z = zs - zp) indicates a dispersion of sigma_{Delta z/(1+zs)}=0.007 at i<22.5, a factor of 2-6 times more accurate than earlier photo-z in the COSMOS, CFHTLS and COMBO-17 survey fields. At fainter magnitudes i<24 and z<1.25, the accuracy is sigma_{Delta z/(1+zs)}=0.012. The deep NIR and IRAC coverage enables the photo-z to be extended to z~2 albeit with a lower accuracy (sigma_{Delta z/(1+zs)}=0.06 at i~24). The redshift distribution of large magnitude-selected samples is derived and the median redshift is found to range from z=0.66 at 22Comment: 21 pages, 14 figures, and 3 tables ; accepted for publication in ApJ |
| Databáze: |
arXiv |
| Externí odkaz: |
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