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arXiv · 2207.13459

Early results from GLASS-JWST. VI: Extreme rest-optical equivalent widths detected in NIRISS Wide Field Slitless Spectroscopy

K. Boyett·S. Mascia·L. Pentericci·N. Leethochawalit·M. Trenti·G. Brammer·G. Roberts-Borsani·V. Strait·T. Treu·M. Bradac·K. Glazebrook·A. Acebron·P. Bergamini·A. Calabro`·M. Castellano·A. Fontana·C. Grillo·A. Henry·T. Jones·D. Marchesini·C. Mason·A. Mercurio·T. Morishita·T. Nanayakkara·P. Rosati·C. Scarlata·E. Vanzella·B. Vulcani·X. Wang·C. Willott
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Abstract

Wide Field Slitless Spectroscopy (WFSS) provides a powerful tool for detecting strong line emission in star forming galaxies (SFGs) without the need for target pre-selection. As part of the GLASS-JWST-ERS program, we leverage the near-infrared wavelength capabilities of NIRISS ($1-2.2\mu$m) to observe rest-optical emission lines out to $\rm{z}\sim 3.4$, to a depth and with a spatial resolution higher than ever before (H$\alpha$ to z<2.4; [OIII]+H$\beta$ to z<3.4). In this letter we constrain the rest-frame [OIII]$\lambda5007$ equivalent width (EW) distribution for a sample of 76 $1<\rm{z}<3.4$ SFGs in the Abell 2744 Hubble Frontier Field and determine an abundance fraction of extreme emission line galaxies with EW$>750$A in our sample to be $12\%$. We determine a strong correlation between the measured H$\beta$ and [OIII]$\lambda5007$ EWs, supporting that the high [OIII]$\lambda5007$ EW objects require massive stars in young stellar populations to generate the high energy photons needed to doubly ionise oxygen. We extracted spectra for objects up to 2 mag fainter in the near-infrared than previous WFSS studies with the Hubble Space Telescope. Thus, this work clearly highlights the potential of JWST/NIRISS to provide high quality WFSS datasets in crowded cluster environments.

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K. Boyett, S. Mascia, L. Pentericci, N. Leethochawalit, M. Trenti, G. Brammer, G. Roberts-Borsani, V. Strait, T. Treu, M. Bradac, K. Glazebrook, A. Acebron, P. Bergamini, A. Calabro`, M. Castellano, A. Fontana, C. Grillo, A. Henry, T. Jones, D. Marchesini, C. Mason, A. Mercurio, T. Morishita, T. Nanayakkara, P. Rosati, C. Scarlata, E. Vanzella, B. Vulcani, X. Wang, C. Willott. 2022-07-27. Early results from GLASS-JWST. VI: Extreme rest-optical equivalent widths detected in NIRISS Wide Field Slitless Spectroscopy. https://doi.org/10.3847/2041-8213%2Fac9f17

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