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arXiv · 1612.01526

Paving the way for the JWST: witnessing globular cluster formation at z>3

E. Vanzella·F. Calura·M. Meneghetti·A. Mercurio·M. Castellano·G. B. Caminha·I. Balestra·P. Rosati·P. Tozzi·S. De Barros·A. Grazian·A. D'Ercole·L. Ciotti·K. Caputi·C. Grillo·E. Merlin·L. Pentericci·A. Fontana·S. Cristiani·D. Coe
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Abstract

We report on five compact, extremely young (<10Myr) and blue (\beta_UV<-2.5, F_\lambda =\lambda^\beta) objects observed with VLT/MUSE at redshift 3.1169, 3.235, in addition to three objects at z=6.145. These sources are magnified by the Hubble Frontier Field galaxy clusters MACS~J0416 and AS1063. Their de-lensed half light radii (Re) are between 16 to 140pc, the stellar masses are ~1-20 X 10^6 Msun, the magnitudes are m_uv=28.8 - 31.4 (-17 3, elusive even in the deepest blank fields. We discuss how proto-GCs might contribute to the ionization budget of the universe and augment Lya visibility during reionization. This work underlines the crucial role of JWST in characterizing the rest-frame optical and near-infrared properties of such low-luminosity high-z objects.

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E. Vanzella, F. Calura, M. Meneghetti, A. Mercurio, M. Castellano, G. B. Caminha, I. Balestra, P. Rosati, P. Tozzi, S. De Barros, A. Grazian, A. D'Ercole, L. Ciotti, K. Caputi, C. Grillo, E. Merlin, L. Pentericci, A. Fontana, S. Cristiani, D. Coe. 2016-12-05. Paving the way for the JWST: witnessing globular cluster formation at z>3. https://doi.org/10.1093/mnras%2Fstx351

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