简介: |
With the HST near-infrared grism spectroscopy from the supernova Refsdal follow-up program and the Grism Lens-Amplified Survey from Space, we observe the cycle of baryons and metals in the low-mass regime of galaxies at the peak epoch of cosmic star formation. I will present the first results on the gas-phase oxygen abundance (metallicity) radial gradient measurements in a sample of 12 star-forming galaxies at z=1.2~2.3, with high spatial sampling (sub-kpc scales in the source plane), in the field of the Hubble Frontier Field cluster MACS1149.6+2223. The synergy of ultra deep diffraction-limited exposure and lensing magnification offers a great gain in source plane angular resolution and emission line limiting flux, which makes this study unique in all high-z metallicity gradient analyses so far. We obtain a number of flat metallicity gradients in isolated galaxies, suggesting strong radial mixing and disfavoring weak galactic feedback models.
Bio: Mr. Xin Wang obtained his B.Sc. and M.Sc. from Nanjing University in 2010 and 2013 respectively, and obtained M.A. in Physics from University of California Santa Barbara in 2015. Now he is a PhD candidate in Department of Physics and Astronomy at University of California Los Angeles. Xin is interested in probing high-redshift galaxy formation and evolution using spatially resolved spectroscopy. In particular, he is measuring gas-phase metallicity and metallicity radial gradients in z>1 star-forming galaxies with the WFC3/IR grisms on the Hubble Space Telescope, in order to study the cycle of baryons and metals in and out of galaxies, and trace gas inflows and outflows. Xin has also been working on gravitational lensing reconstruction of the mass distribution of galaxy clusters, and improve the source plane morphology reconstruction of multiply imaged galaxies. Previously, Xin was working in the fields of cosmology and gamma-ray bursts. |
