CLASH: discovery of a bright z[simeq]6.2 dwarf galaxy quadruply lensed by MACS J0329.6-0211
We report the discovery of a z phot = 6.18 +0.05 - 0.07 (95% confidence level) dwarf galaxy, lensed into four images by the galaxy cluster MACS J0329.6-0211 ( z l = 0.45). The galaxy is observed as a high-redshift dropout in HST /ACS/WFC3 CLASH and Spitzer /IRAC imaging. Its redshift is securely det...
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| Main Author: | |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
2012 February 10
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| In: |
The astrophysical journal. Part 2, Letters
Year: 2012, Volume: 747, Issue: 1 |
| ISSN: | 2041-8213 |
| DOI: | 10.1088/2041-8205/747/1/L9 |
| Online Access: | Verlag, kostenfrei, Volltext: http://dx.doi.org/10.1088/2041-8205/747/1/L9 Verlag, kostenfrei, Volltext: http://stacks.iop.org/2041-8205/747/i=1/a=L9 |
| Author Notes: | A. Zitrin, J. Moustakas, L. Bradley, D. Coe, L.A. Moustakas, M. Postman, X. Shu, W. Zheng, N. Benítez, R. Bouwens, T. Broadhurst, H. Ford, O. Host, S. Jouvel, A. Koekemoer, M. Meneghetti, P. Rosati, M. Donahue, C. Grillo, D. Kelson, D. Lemze, E. Medezinski, A. Molino, M. Nonino, and S. Ogaz |
| Summary: | We report the discovery of a z phot = 6.18 +0.05 - 0.07 (95% confidence level) dwarf galaxy, lensed into four images by the galaxy cluster MACS J0329.6-0211 ( z l = 0.45). The galaxy is observed as a high-redshift dropout in HST /ACS/WFC3 CLASH and Spitzer /IRAC imaging. Its redshift is securely determined due to a clear detection of the Lyman break in the 18-band photometry, making this galaxy one of the highest-redshift multiply lensed objects known to date with an observed magnitude of F125W =24.00 ± 0.04 AB mag for its most magnified image. We also present the first strong-lensing analysis of this cluster uncovering 15 additional multiply imaged candidates of five lower-redshift sources spanning the range z s ##IMG## [http://ej.iop.org/icons/Entities/sime.gif] sime 2-4. The mass model independently supports the high photometric redshift and reveals magnifications of 11.6 +8.9 - 4.1 , 17.6 +6.2 - 3.9 , 3.9 +3.0 - 1.7 , and 3.7 +1.3 - 0.2 , respectively, for the four images of the high-redshift galaxy. By delensing the most magnified image we construct an image of the source with a physical resolution of 200 pc when the universe was 0.9 Gyr old, where the z ##IMG## [http://ej.iop.org/icons/Entities/sime.gif] sime 6.2 galaxy occupies a source-plane area of approximately 2.2 kpc 2 . Modeling the observed spectral energy distribution using population synthesis models, we find a demagnified stellar mass of ##IMG## [http://ej.iop.org/images/2041-8205/747/1/L9/apjl421305ieqn1.gif] $\sim10^9 \,\mathcal M_ødot $ , subsolar metallicity ( Z / Z ☉ 0.5), low dust content ( A V 0.1 mag), a demagnified star formation rate (SFR) of ##IMG## [http://ej.iop.org/images/2041-8205/747/1/L9/apjl421305ieqn2.gif] $\sim3.2 \,\mathcal M_ødot $ yr -1 , and a specific SFR of 3.4 Gyr -1 , all consistent with the properties of local dwarf galaxies. |
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| Item Description: | Im Titel steht nach "z" "tilde" über "Unterstrich" Gesehen am 18.10.2018 |
| Physical Description: | Online Resource |
| ISSN: | 2041-8213 |
| DOI: | 10.1088/2041-8205/747/1/L9 |