parameters of this galaxy with other dusty starbursts favor the $z\sim2$ mid-infrared photometric redshift. The data presented here provide evidence that optically undetected near-infrared sources which are detected at 24$\mu$m are most likely dusty, starburst galaxies at a redshift of $z\sim2$ with stellar masses $>$10$^{10}$ M$_{\sun}$.'
author:
- 'Ranga-Ram Chary, Harry I. Teplitz, Mark E. Dickinson, David C. Koo, Emeric Le Floc’h, Delphine Marcillac, Casey Papovich, Daniel Stern'
title: 'HUDF-JD2: Mid-infrared Evidence for a $z\sim2$ Luminous Infrared Galaxy'
---

Introduction
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JD2 is an interesting object in the Hubble Ultradeep Field [UDF; @RIT; @Beckwith]. Its non-detection shortward of the 1.1$\mu$m bandpass, even in ultradeep Advanced Camera for Surveys (ACS) UDF optical data which are sensitive down to $\sim$29 AB mag, has been interpreted as being due to the redshifted Lyman break. In addition, it displays a break in its broad band spectral energy distribution (SED) between 2.2$\mu$m and 3.6$\mu$m which has been interpreted as the redshifted Balmer break. @Mobasher argue that it may be a very massive (6$\times$10$^{11}$ M$_{\sun}$) galaxy with very little ongoing star-formation at $z\sim6.5$. The large stellar mass of this galaxy derived from fitting population synthesis models to the multiband photometry, and high source density implied by 