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We report a Plateau de Bure interferometer search for CII-158$mu$m emission from HCM6A, a lensed Lyman-$alpha$ emitter (LAE) at $z = 6.56$. Our non-detections of CII-158$mu$m line emission and 1.2mm radio continuum emission yield $3sigma$ limits of L$_{rm CII} < 6.4 times 10^7 times (Delta V/100 km s^{-1})^{1/2}$ L$_odot$ on the CII-158$mu$m line luminosity and S$_{rm 1.2mm} < 0.68$ mJy on the 1.2mm flux density. The local conversion factor between L$_{rm CII}$ and star formation rate (SFR) yields an SFR $< 4.7$ M$_odot$ yr$^{-1}$, $approx 2$ times lower than that inferred from the ultraviolet (UV) continuum, suggesting that the local factor may not be applicable in high-$z$ LAEs. The non-detection of 1.2mm continuum emission yields a total SFR $< 28$ M$_odot$/yr; any obscured star formation is thus within a factor of two of the visible star formation. Our best-fit model to the rest-frame UV/optical spectral energy distribution of HCM6A yields a stellar mass of $1.3 times 10^9$ M$_odot$ and an SFR of ~10 M$_odot$/yr, with negligible dust obscuration. We fortuitously detect CO J=3-2 emission from a $z=0.375$ galaxy in the foreground cluster Abell370, obtaining a CO line luminosity of L$^prime ({rm CO}) > (8.95 pm 0.79) times 10^8$ K km s$^{-1}$ pc$^2$, and a molecular gas mass of M$({rm H_2}) > (4.12 pm 0.36) times 10^9$ M$_odot$, for a CO-to-H$_2$ conversion factor of 4.6 M$_odot$ (K km s$^{-1}$ pc$^2$)$^{-1}$.
The [CII] 157.74 $mu$m transition is the dominant coolant of the neutral interstellar gas, and has great potential as a star formation rate (SFR) tracer. Using the Herschel KINGFISH sample of 46 nearby galaxies, we investigate the relation of [CII] s
The scatter in the relationship between the strength of [CII] 158$mu$m emission and the star formation rate at high-redshift has been the source of much recent interest. Although the relationship is well-established locally, several intensely star-fo
We study the effects of a metallicity variation on the thermal balance and [CII] fine-structure line strengths in interstellar photon dominated regions (PDRs). We find that a reduction in the dust-to-gas ratio and the abundance of heavy elements in t
We present new ALMA observations and physical properties of a Lyman Break Galaxy at z=7.15. Our target, B14-65666, has a bright ultra-violet (UV) absolute magnitude, $M_{rm UV}approx-22.4$, and has been spectroscopically identified in Ly$alpha$ with
We consider the capabilities of ALMA and the ngVLA to detect and image the[CII] 158,$mu$m line from galaxies into the cosmic `dark ages ($z sim 10$ to 20). The [CII] line may prove to be a powerful tool in determining spectroscopic redshifts, and gal