Shape and intrusion history of the Late Caledonian Newry Igneous Complex, Northern Ireland

The Tellus high-resolution airborne magnetic and radiometric maps define previously unmapped zones within the Newry Igneous Complex, County Down. High-precision uranium–lead zircon dating of nine rock samples from different parts of the complex provides a robust set of age constraints (c.414–407 Ma), which confirm that the different plutons of the complex young towards the south-west. Combined, these new data allow an innovative model of intrusion to be developed, with intrusion beginning in the north-east and progressing towards the south-west

Seasonal Expression of the Picocyanobacterial Phosphonate Transporter Gene phnD in the Sargasso Sea

In phosphorus-limited marine environments, picocyanobacteria (Synechococcus and Prochlorococcus spp.) can hydrolyze naturally occurring phosphonates as a P source. Utilization of 2-aminoethylphosphonate (2-AEP) is dependent on expression of the phn genes, encoding functions required for uptake, and C–P bond cleavage. Prior work has indicated that expression of picocyanobacterial phnD, encoding the phosphonate binding protein of the phosphonate ABC transporter, is a proxy for the assimilation of phosphonates in natural assemblages of Synechococcus spp. and Prochlorococcus spp (Ilikchyan et al., 2009). In this study, we expand this work to assess seasonal phnD expression in the Sargasso Sea. By RT-PCR, our data confirm that phnD expression is constitutive for the Prochlorococcus spp. detected, but in Synechococcus spp. phnD transcription follows patterns of phosphorus availability in the mixed layer. Specifically, our data suggest that phnD is repressed in the spring when P is bioavailable following deep winter mixing. In the fall, phnD expression follows a depth-dependent pattern reflecting depleted P at the surface following summertime drawdown, and elevated P at depth

Radio imaging of the Subaru/XMM-Newton Deep Field - III. Evolution of the radio luminosity function beyond z=1

We present spectroscopic and eleven-band photometric redshifts for galaxies in the 100-uJy Subaru/XMM-Newton Deep Field radio source sample. We find good agreement between our redshift distribution and that predicted by the SKA Simulated Skies project. We find no correlation between K-band magnitude and radio flux, but show that sources with 1.4-GHz flux densities below ~1mJy are fainter in the near-infrared than brighter radio sources at the same redshift, and we discuss the implications of this result for spectroscopically-incomplete samples where the K-z relation has been used to estimate redshifts. We use the infrared--radio correlation to separate our sample into radio-loud and radio-quiet objects and show that only radio-loud hosts have spectral energy distributions consistent with predominantly old stellar populations, although the fraction of objects displaying such properties is a decreasing function of radio luminosity. We calculate the 1.4-GHz radio luminosity function (RLF) in redshift bins to z=4 and find that the space density of radio sources increases with lookback time to z~2, with a more rapid increase for more powerful sources. We demonstrate that radio-loud and radio-quiet sources of the same radio luminosity evolve very differently. Radio-quiet sources display strong evolution to z~2 while radio-loud AGNs below the break in the radio luminosity function evolve more modestly and show hints of a decline in their space density at z>1, with this decline occurring later for lower-luminosity objects. If the radio luminosities of these sources are a function of their black hole spins then slowly-rotating black holes must have a plentiful fuel supply for longer, perhaps because they have yet to encounter the major merger that will spin them up and use the remaining gas in a major burst of star formation.Comment: Accepted for publication in MNRAS: 36 pages, including 13 pages of figures to appear online only. In memory of Stev

The Allen Telescope Array Twenty-centimeter Survey - A 690-Square-Degree, 12-Epoch Radio Dataset - I: Catalog and Long-Duration Transient Statistics

We present the Allen Telescope Array Twenty-centimeter Survey (ATATS), a multi-epoch (12 visits), 690 square degree radio image and catalog at 1.4GHz. The survey is designed to detect rare, very bright transients as well as to verify the capabilities of the ATA to form large mosaics. The combined image using data from all 12 ATATS epochs has RMS noise sigma = 3.94mJy / beam and dynamic range 180, with a circular beam of 150 arcsec FWHM. It contains 4408 sources to a limiting sensitivity of S = 20 mJy / beam. We compare the catalog generated from this 12-epoch combined image to the NRAO VLA Sky Survey (NVSS), a legacy survey at the same frequency, and find that we can measure source positions to better than ~20 arcsec. For sources above the ATATS completeness limit, the median flux density is 97% of the median value for matched NVSS sources, indicative of an accurate overall flux calibration. We examine the effects of source confusion due to the effects of differing resolution between ATATS and NVSS on our ability to compare flux densities. We detect no transients at flux densities greater than 40 mJy in comparison with NVSS, and place a 2-sigma upper limit on the transient rate for such sources of 0.004 per square degree. These results suggest that the > 1 Jy transients reported by Matsumura et al. (2009) may not be true transients, but rather variable sources at their flux density threshold.Comment: 41 pages, 19 figures, ApJ accepted; corrected minor typo in Table

The Allen Telescope Array Pi GHz Sky Survey I. Survey Description and Static Catalog Results for the Bootes Field

The Pi GHz Sky Survey (PiGSS) is a key project of the Allen Telescope Array. PiGSS is a 3.1 GHz survey of radio continuum emission in the extragalactic sky with an emphasis on synoptic observations that measure the static and time-variable properties of the sky. During the 2.5-year campaign, PiGSS will twice observe ~250,000 radio sources in the 10,000 deg^2 region of the sky with b > 30 deg to an rms sensitivity of ~1 mJy. Additionally, sub-regions of the sky will be observed multiple times to characterize variability on time scales of days to years. We present here observations of a 10 deg^2 region in the Bootes constellation overlapping the NOAO Deep Wide Field Survey field. The PiGSS image was constructed from 75 daily observations distributed over a 4-month period and has an rms flux density between 200 and 250 microJy. This represents a deeper image by a factor of 4 to 8 than we will achieve over the entire 10,000 deg^2. We provide flux densities, source sizes, and spectral indices for the 425 sources detected in the image. We identify ~100$ new flat spectrum radio sources; we project that when completed PiGSS will identify 10^4 flat spectrum sources. We identify one source that is a possible transient radio source. This survey provides new limits on faint radio transients and variables with characteristic durations of months.Comment: Accepted for publication in ApJ; revision submitted with extraneous figure remove

Breaking the "Redshift Deadlock" -- II: The redshift distribution for the submillimetre population of galaxies

In this paper we apply our Monte-Carlo photometric-redshift technique, introduced in paper I (Hughes et al. 2002), to the multi-wavelength data available for 77 galaxies selected at 850um and 1.25mm. We calculate a probability distribution for the redshift of each galaxy, which includes a detailed treatment of the observational errors and uncertainties in the evolutionary model. The cumulative redshift distribution of the submillimetre galaxy population that we present in this paper, based on 50 galaxies found in wide-area SCUBA surveys, is asymmetric, and broader than those published elsewhere, with a significant high-z tail for some of the evolutionary models considered. Approximately 40 to 90 per cent of the sub-mm population is expected to have redshifts in the interval 2 < z < 4. Whilst this result is completely consistent with earlier estimates for the sub-mm galaxy population, we also show that the colours of many (< 50 per cent) individual sub-mm sources, detected only at 850um with non-detections at other wavelengths, are consistent with those of starburst galaxies that lie at extreme redshifts, z > 4. Spectroscopic confirmation of the redshifts, through the detection of rest-frame FIR--mm wavelength molecular transition-lines, will ultimately calibrate the accuracy of this technique. We use the redshift probability distribution of HDF850.1 to illustrate the ability of the method to guide the choice of possible frequency tunings on the broad-band spectroscopic receivers that equip the large aperture single-dish mm and cm-wavelength telescopes.Comment: Accepted in MNRAS, 16 pages, 12 figures, an appendix with 25 additional pages of figures is available at http://www.inaoep.mx/~itziar/papers/dlIIapp.pd

The Australia Telescope Large Area Survey: Spectroscopic catalogue and radio luminosity functions

The Australia Telescope Large Area Survey (ATLAS) has surveyed 7 square degrees of sky around the Chandra Deep Field South and the European Large Area ISO Survey-South 1 fields at 1.4 GHz. ATLAS aims to reach a uniform sensitivity of 10 μJy beam−1 rms over the entire region with first data release currently reaching ∼ 30 μJy beam−1 rms. Here we present 466 new spectroscopic redshifts for radio sources in ATLAS as part of our optical follow-up programme. Of the 466 radio sources with new spectroscopic redshifts, 142 have star-forming optical spectra, 282 show evidence for active galactic nuclei (AGN) in their optical spectra, 10 have stellar spectra and 32 have spectra revealing redshifts, but with insufficient features to classify. We compare our spectroscopic classifications with two mid-infrared diagnostics and find them to be in broad agreement. We also construct the radio luminosity function for star-forming galaxies to z = 0.5 and for AGN to z = 0.8. The radio luminosity function for star-forming galaxies appears to be in good agreement with previous studies. The radio luminosity function for AGN appears higher than previous studies of the local AGN radio luminosity function. We explore the possibility of evolution, cosmic variance and classification techniques affecting the AGN radio luminosity function. ATLAS is a pathfinder for the forthcoming Evolution Map of the Universe (EMU) survey and the data presented in this paper will be used to guide EMU's survey design and early science papers

Crop Updates 2001 - Cereals

This session covers forty two papers from different authors: PLENARY 1. Planning your cropping program in season 2001, Dr Ross Kingwell, Agriculture Western Australia and University of Western Australia WORKSHOP 2. Can we produce high yields without high inputs? Wal Anderson, Centre for Cropping Systems, Agriculture Western Australia VARIETIES 3. Local and interstate wheat variety performance and $ return to WA growers, Eddy Pol, Peter Burgess and Ashley Bacon, Agritech Crop Research CROP ESTABLISHMENT 4 Soil management of waterlogged soils, D.M. Bakker, G.J. Hamilton, D. Houlbrooke and C. Spann, Agriculture Western Australia 5. Effect of soil amelioration on wheat yield in a very dry season, M.A Hamza and W.K. Anderson, Agriculture Western Australia 6. Fuzzy tramlines for more yield and less weed, Paul Blackwell1 and Maurice Black2 1Agriculture Western Australia, 2Harbour Lights Estate, Geraldton 7. Tramline farming for dollar benefits, Paul Blackwell, Agriculture Western Australia NUTRITION 8. Soil immobile nutrients for no-till crops, M.D.A. Bolland1, R.F. Brennan1,and W.L. Crabtree2, 1Agriculture Western Australia, 2Western Australian No-Tillage Farmers Association 9. Burn stubble windrows: to diagnose soil fertility problems, Bill Bowden, Chris Gazey and Ross Brennan, Agriculture Western Australia 10. Calcium: magnesium ratios; are they important? Bill Bowden1, Rochelle Strahan2, Bob Gilkes2 and Zed Rengel2 1Agriculture Western Australia, 2Department of Soil Science and Plant Nutrition, UWA 11. Responses to late foliar applications of Flexi-N, Stephen Loss, Tim O’Dea, Patrick Gethin, Ryan Guthrie, Lisa Leaver, CSBP futurefarm 12. A comparison of Flexi-N placements, Stephen Loss, Tim O’Dea, Patrick Gethin, Ryan Guthrie, Lisa Leaver, CSBP futurefarm 13. What is the best way to apply potassium? Stephen Loss, Tim O’Dea, Patrick Gethin, Ryan Guthrie, CSBP futurefarm 14. Claying affects potassium nutrition in barley, Stephen Loss, David Phelps, Tim O’Dea, Patrick Gethin, Ryan Guthrie, Lisa Leaver, CSBP futurefarm 15. Nitrogen and potassium improve oaten hay quality, Stephen Loss, Tim O’Dea, Patrick Gethin, Ryan Guthrie, Lisa Leaver, CSBP futurefarm AGRONOMY 16. Agronomic responses of new wheat varieties in the northern wheatbelt, Darshan Sharma and Wal Anderson, Agriculture Western Australia 17. Wheat agronomy research on the south coast, Mohammad Amjad and Wal Anderson, Agriculture Western Australia 18. Influence of sowing date on wheat yield and quality in the south coast environment, Mohammad Amjadand Wal Anderson, Agriculture Western Australia 19. More profit from durum, Md.Shahajahan Miyan and Wal Anderson, Agriculture Western Australia 20. Enhancing recommendations of flowering and yield in wheat, JamesFisher1, Senthold Asseng2, Bill Bowden1 and Michael Robertson3 ,1AgricultureWestern Australia, 2CSIRO Plant Industry, 3CSIRO Sustainable Ecosystems 21. When and where to grow oats, Glenn McDonald, Agriculture Western Australia 22. Managing Gaidner barley for quality, Kevin Young and Blakely Paynter, Agriculture Western Australia PESTS AND DISEASES 23. Strategies for leaf disease management in wheat, Jatinderpal Bhathal1, Cameron Weeks2, Kith Jayasena1 and Robert Loughman1 ,1Agriculture Western Australia. 2Mingenew-Irwin Group Inc 24. Strategies for leaf disease management in malting barley, K. Jayasena1, Q. Knight2 and R. Loughman1, 1Agriculture Western Australia, 2IAMA Agribusiness 25. Cereal disease diagnostics, Dominie Wright and Nichole Burges, Agriculture Western Australia 26. The big rust: Did you get your money back!! Peter Burgess, Agritech Crop Research 27. Jockey – winning the race against disease in wheat, Lisa-Jane Blacklow, Rob Hulme and Rob Giffith, Aventis CropScience 28. Distribution and incidence of aphids and barley yellow dwarf virus in over-summering grasses in WA wheatbelt, Jenny Hawkes and Roger Jones, CLIMA and Agriculture Western Australia 29. Further developments in forecasting aphid and virus risk in cereals, Debbie Thackray, Jenny Hawkes and Roger Jones, Agriculture Western Australia and Centre for Legumes in Mediterranean Agriculture 30. Effect of root lesion nematodes on wheat yields in Western Australia, S. B. Sharma, S. Kelly and R. Loughman, Crop Improvement Institute, Agriculture Western Australia 31. Rotational crops and varieties for management of root lesion nematodes in Western Australia, S.B. Sharma, S. Kelly and R. Loughman, Crop Improvement Institute, Agriculture Western Australia WEEDS 32. Phenoxy herbicide tolerance of wheat, Peter Newman and Dave Nicholson, Agriculture Western Australia 33. Tolerance of wheat to phenoxy herbicides,Harmohinder S. Dhammu, Terry Piper and Mario F. D\u27Antuono, Agriculture Western Australia 34. Herbicide tolerance of durum wheats, Harmohinder S. Dhammu, Terry Piper and David Nicholson, Agriculture Western Australia 35. Herbicide tolerance of new wheats, Harmohinder S. Dhammu, Terry Piper and David F. Nicholson, Agriculture Western Australia BREEDING 36. Towards molecular breeding of barley: construction of a molecular genetic map, Mehmet Cakir1, Nick Galwey1, David Poulsen2, Garry Ablett3, Reg Lance4, Rob Potter5 and Peter Langridge6,1Plant Sciences, Faculty of Agriculture, UWA, 2Queensland Department of Primary Industries, Qld, 3Centre for Plant Conservation Genetics Southern Cross University, Lismore NSW, 5SABC Murdoch University, WA, 6Department of Plant Science University of Adelaide, Glen Osmond SA 37. Toward molecular breeding of barley: Identifying markers linked to genes for quantitative traits, Mehmet Cakir1, Nick Galwey1, David Poulsen2, Reg Lance3, Garry Ablett4, Greg Platz2, Joe Panozzo5, Barbara Read6, David Moody5, Andy Barr7 and Peter Langridge7 , 1Plant Sciences, Faculty of Agriculture, UWA, 2Queensland Department of Primary Industries, Warwick, QLD,3Agriculture Western Australia, 4Centre for Plant Conservation Genetics, Southern Cross University, Lismore NSW, 5VIDA Private Bag 260, Horsham VIC, 6NSW Dept. of Agriculture, Wagga Wagga NSW, 7Department of Plant Science, University of Adelaide, Glen Osmond SA 38. Can we improve grain yield by breeding for greater early vigour in wheat? Tina Botwright1, Tony Condon1, Robin Wilson2 and Iain Barclay2, 1CSIRO Plant Industry, 2Agriculture Western Australia MARKETING AND QUALITY 39. The Crop Improvement Royalty, Howard Carr, Agriculture Western Australia 40. GrainGuardÔ - The development of a protection plan for the wheat industry, Greg Shea, Agriculture Western Australia CLIMATE 41. Rainfall – what happened in 2000 and the prospects for 2001, Ian Foster, Agriculture Western Australia 42. Software for climate management issues, David Tennant,Agriculture Western Australia CONTRIBUTING AUTHOR CONTACT DETAIL

Radio Continuum Surveys with Square Kilometre Array Pathfinders

In the lead-up to the Square Kilometre Array (SKA) project, several next-generation radio telescopes and upgrades are already being built around the world. These include APERTIF (The Netherlands), ASKAP (Australia), e-MERLIN (UK), VLA (USA), e-EVN (based in Europe), LOFAR (The Netherlands), MeerKAT (South Africa), and the Murchison Widefield Array. Each of these new instruments has different strengths, and coordination of surveys between them can help maximise the science from each of them. A radio continuum survey is being planned on each of them with the primary science objective of understanding the formation and evolution of galaxies over cosmic time, and the cosmological parameters and large-scale structures which drive it. In pursuit of this objective, the different teams are developing a variety of new techniques, and refining existing ones. To achieve these exciting scientific goals, many technical challenges must be addressed by the survey instruments. Given the limited resources of the global radio-astronomical community, it is essential that we pool our skills and knowledge. We do not have sufficient resources to enjoy the luxury of re-inventing wheels. We face significant challenges in calibration, imaging, source extraction and measurement, classification and cross-identification, redshift determination, stacking, and data-intensive research. As these instruments extend the observational parameters, we will face further unexpected challenges in calibration, imaging, and interpretation. If we are to realise the full scientific potential of these expensive instruments, it is essential that we devote enough resources and careful study to understanding the instrumental effects and how they will affect the data. We have established an SKA Radio Continuum Survey working group, whose prime role is to maximise science from these instruments by ensuring we share resources and expertise across the projects. Here we describe these projects, their science goals, and the technical challenges which are being addressed to maximise the science return