The SCUBA Local Universe Galaxy Survey

The SCUBA local universe galaxy survey is the first systematic survey of the local universe at submillimetre wavelengths. We have observed ~200 galaxies from the IRAS bright galaxy catalogue and the CfA optical redshift survey. The IRAS sample showed that our estimate of the luminosity function was potentially biased if a cold population of galaxies existed which would not have appeared in the IRAS BGS but would have been detected in a SCUBA blind survey. Here we present preliminary results from the optically selected sample which suggest that this is indeed the case.Comment: 2 pages, 2 figs, proceedings from Euro-conference on galaxy evolution held in La Reunion, 200

TESTING SEPARABILITY OF JAPANESE DEMAND FOR MEAT AND FISH WITHIN DIFFERENTIAL DEMAND SYSTEMS

The separability of meat products from fish products is investigated to gain a better understanding of Japanese consumer choices in protein demand. Rather than view fish as a single homogeneous commodity, fish and seafood are categorized into several groups of products. Separability is investigated using a demand system approach in which a generalized system of demand equations is specified and used, first to identify if any of the alternative demand structures nested within the general system are appropriate for these data, and then, conditional on those results, to test separability of meats from fish products following Moschini, Moro, and Green. Results indicate that meats and fish were separable prior to 1990; however, when examined over the entire 1981-95 study period, they are not.Demand and Price Analysis,

Demand Elasticities for Fresh Fruit at the Retail Level

The obesity epidemic in the US and elsewhere has re-doubled efforts to understand determinants of the quality of consumers' diets. Part of the discussion has centered on the potential of "fat taxes" and/or the subsidization of the purchase of fresh fruits and vegetables to coax consumers to better diets. Whether this discussion has merit or not, fundamental to the debate are the demand elasticities of the commodities involved. This study employs weekly data from several retail stores on fruit prices and sales to estimate elasticities of individual fruits. Estimates show consumers are more responsive to price than has been found previously.Consumer/Household Economics,

Candidate High Redshift and Primeval Galaxies in Hubble Deep Field South

We present the results of colour selection of candidate high redshift galaxies in Hubble Deep Field South (HDF-S) using the Lyman dropout scheme. The HDF-S data we discuss were taken in a number of different filters extending from the near--UV (F300W) to the infrared (F222M) in two different fields. This allows us to select candidates with redshifts from z~3 to z~12. We find 15 candidate z~3 objects (F300W dropouts), 1 candidate z~4 object (F450W dropout) and 16 candidate z$\sim$5 objects (F606W dropouts) in the ~ 4.7 arcmin^2 WFPC-2 field, 4 candidate z~6 (optical dropouts) and 1 candidate z~8 (F110W dropout) in the 0.84 arcmin^2 NICMOS-3 field. No F160W dropouts are found (z~12). We compare our selection technique with existing data for HDF-North and discuss alternative interpretations of the objects. We conclude that there are a number of lower redshift interlopers in the selections, including one previously identified object (Treu et al. 1998), and reject those objects most likely to be foreground contaminants. Even after this we conclude that the F606W dropout list is likely to still contain substantial foreground contamination. The lack of candidate very high redshift UV-luminous galaxies supports earlier conclusions by Lanzetta et al. (1998). We discuss the morphologies and luminosity functions of the high redshift objects, and their cosmological implications.Comment: Accepted for publication in MNRA

Upper limits on K-band polarization in three high-redshift radio galaxies: LBDS 53W091, 3C 441 and MRC 0156-252

We present the results of K-band imaging polarimetry of three radio galaxies, including the very red and apparently old z=1.55 galaxy 53W091. We find weak evidence for polarization in components of 3C 441 and in the south-east companion of 53W091, but no evidence of significant polarization in 53W091 itself. We also find strong evidence that MRC 0156-252 is unpolarised. We present upper limits for the K-band polarization of all three sources. For 53W091, the lack of significant K-band polarization provides further confidence that its red R-K colour can be attributed to a mature stellar population, consistent with the detailed analyses of its ultraviolet spectral-energy distribution which indicate a minimum age of 2-3.5 Gyr.Comment: 7 pages, 3 postscript figures. In press at MNRA

A new method to measure evolution of the galaxy luminosity function

We present a new efficient technique for measuring evolution of the galaxy luminosity function. The method reconstructs the evolution over the luminosity-redshift plane using any combination of three input dataset types: 1) number counts, 2) galaxy redshifts, 3) integrated background flux measurements. The evolution is reconstructed in adaptively sized regions of the plane according to the input data as determined by a Bayesian formalism. We demonstrate the performance of the method using a range of different synthetic input datasets. We also make predictions of the accuracy with which forthcoming surveys conducted with SCUBA2 and the Herschel Space Satellite will be able to measure evolution of the sub-millimetre luminosity function using the method.Comment: MNRAS in press. 14 pages, 7 figures

The Canada-UK Deep Submillimetre Survey: First Submillimetre Images, the Source Counts, and Resolution of the Background

We present the first results of a deep unbiased submillimetre survey carried out at 450 and 850 microns. We detected 12 sources at 850 microns, giving a surface density of sources with 850-micron flux densities > 2.8mJy of of 0.49+-0.16 per square arcmin. The sources constitute 20-30% of the background radiation at 850 microns and thus a significant fraction of the entire background radiation produced by stars. This implies, through the connection between metallicity and background radiation, that a significant fraction of all the stars that have ever been formed were formed in objects like those detected here. The combination of their large contribution to the background radiation and their extreme bolometric luminosities make these objects excellent candidates for being proto-ellipticals. Optical astronomers have recently shown that the UV-luminosity density of the universe increases by a factor of about 10 between z=0 and z=1 and then decreases again at higher redshifts. Using the results of a parallel submillimetre survey of the local universe, we show that both the submillimetre source density and background can be explained if the submillimetre luminosity density evolves in a similar way to the UV-luminosity density. Thus, if these sources are ellipticals in the process of formation, they may be forming at relatively modest redshifts.Comment: 8 pages (LATEX), 6 postscript figures, submitted to ApJ Letter

K-band polarimetry of seven high-redshift radio galaxies

We present the results of K-band imaging polarimetry of seven 3CR radio galaxies at redshifts (z) between 0.7 and 1.2. We find strong evidence for polarization in three sources: 3C 22, 3C 41 and 3C 114. Of these, 3C 41 shows strong evidence of having a quasar core whose infrared light is scattered by dust. We also find some evidence for polarization in 3C 54 and in 3C 356. The two pointlike sources (3C 22 and 3C 41) and the barely-elongated 3C 54 appear to have of order ten per cent of their K-band flux contributed by scattered light from the active nucleus. We conclude that scattered nuclear light can form a significant component of the near-infrared light emitted by high-redshift radio galaxies,and discuss models in which the scattering particles are electrons and dust-grains

A sample of 6C radio sources designed to find objects at redshift z>4: III - imaging and the radio galaxy K-z relation

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