our data. If the IMF varies, then the highest [H$\alpha$]{}-EWs would require very shallow slopes ($\Gamma>-1.0$) with no one slope able to reproduce the data. Thus, the IMF would have to vary stochastically. We conclude that the stellar populations at $z\gtrsim2$ show distinct differences from local populations and there is no simple physical model to explain the large variation in [H$\alpha$]{}-EWs at $z\sim2$.'
author:
- Themiya Nanayakkara
- Karl Glazebrook
- 'Glenn G. Kacprzak'
- Tiantian Yuan
- 'David B. Fisher'
- 'Kim-Vy Tran'
- Lisa Kewley
- Lee Spitler
- Leo Alcorn
- Michael Cowley
- Ivo Labbe
- Caroline Straatman
- Adam Tomczak
bibliography:
- 'bibliography.bib'
title: 'ZFIRE: Using [H$\alpha$]{} Equivalent Widths to Investigate the In Situ Initial Mass Function at $z\sim2$'
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Introduction {#sec:introduction}
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The initial mass function (IMF) or the mass distribution of stars formed in a volume of space at a given time is one of the most fundamental empirically derived relations in astrophysics [@Salpeter1955; @Miller1979; @Kennicutt1983; @Scalo1986b; @Kroupa2001; @Chabrier2003; @Baldry2003]. Since the mass of a star is the primary factor that governs its evolutionary path, the collective evolution of a galaxy is driven strongly by its distribution of stellar masses [@Bastian2010]. Therefore, understanding 