masses and luminosities are a consequence of the high disk surface density.
author:
- 'A.M. Swinbank, Ian Smail, D. Sobral, T. Theuns, P.N. Best, & J.E. Geach,'
title: 'The Properties of the Star-Forming Interstellar Medium at =0.8–2.2 from HiZELS: Star-Formation and Clump Scaling Laws in Gas Rich, Turbulent Disks'
---

Introduction
============

The majority of the stars in the most massive galaxies (M$_{\star}\gsim$10$^{11}$M$_{\odot}$) formed around 8–10billion years ago, an epoch when star formation was at its peak [@Hopkins06; @Sobral12b]. Galaxies at this epoch appear to be gas-rich ($f_{\rm gas}$=20–80%; @Tacconi10 [@Daddi10; @Geach11]) and turbulent [@Lehnert09], with high velocity dispersions given their rotational velocities ($\sigma$=30–100kms$^{-1}$, $v_{\rm max}$/$\sigma\sim
$0.2–1; e.g. @ForsterSchreiber09 [@Genzel08; @Wisnioski11; @Bothwell12]). Within the dense and highly pressurised inter-stellar medium (ISM) of these high-redshift galaxies, it has been suggestes that star formation may be triggered by fragmentation of dynamically unstable gas (in contrast to star-formation occurring in giant molecular clouds in the Milky-Way which continually condense from a stable disk and then dissipate). This process may lead to the to the formation of massive ($\sim $10$^{8-9}$M$_{\odot}$) star-forming regions [e.g.  @ElmegreenD07; @Bournaud09] and give rise to the the clumpy morphologies that are often seen in high-redshift starbursts [@Elmegreen09].

In order to 