ASKAP Capabilities John Reynolds on behalf of the SEIC and ASKAP team

CSIRO. ASKAP Capabilities14 May 2009 Design and construction well underway – many capabilities set To ensure highest priority science is delivered fluidity is retained Announcement of Opportunity, Oct 2008 Proposals due in mid-June 2009, evaluation by Aug 2009 Crystallisation thereafter towards BETR (2010), ASKAP (2013) ASKAP Capability life-cycle

CSIRO. ASKAP Capabilities14 May 2009 “Mode 1” capabilities already defined Matching anticipated survey requirements Continuum imaging Standard spectral line imaging Slow transients Post-commissioning Advanced imaging modes (e.g. postage stamps) “Zoom” (high spectral resolution) modes VLBI & other “fast transients” Rollout

CSIRO. ASKAP Capabilities14 May 2009 Original capabilities, EoI

CSIRO. ASKAP Capabilities14 May 2009 ASKAP Sensitivity (EoI)

CSIRO. ASKAP Capabilities14 May 2009 Basics 36 antennas (configuration by Gupta, Johnston, Feain 2008) 32 beams/antenna 30deg 2 FOV up to ~1.5GHz 50K Tsys, 80% Aperture Efficiency 300MHz instantaneous BW, 20 kHz frequency resolution Frequency range 700 – 1800 MHz, tunable in 16 MHz steps Full polarization (auto/cross products on all beams) 5 second integration time in standard mode

CSIRO. ASKAP Capabilities14 May 2009 ASKAP antenna design 12m – prime focus, f/D = 0.5 Alt+Az+polarisation axes (Sky mount) Surface accuracy 1mm RMS (10 GHz) Slew speeds 3/1/3 degs/sec Acceleration 3/1/3 degs/sec/sec Settling time < 5 seconds

CSIRO. ASKAP Capabilities14 May 2009 Typical u-v histogram for deep image δ = -50º T=10h

CSIRO. ASKAP Capabilities14 May 2009 PAF design 188 elements in octagonal configuration 32 x 2 pol formed beams Independently steerable 30 square degrees up to ~1.5GHz Optimal disposition for tesselation not entirely clear Interlacing (“dithering”) may be required for flatness of field

CSIRO. ASKAP Capabilities14 May 2009 Preliminary design of ASKAP-sized array 11x10 minus some corner elements 188 active pairs

CSIRO. ASKAP Capabilities14 May channel FPA LNA Filtercard assembly

CSIRO. ASKAP Capabilities14 May 2009 FOV vs # beams Beams touching at the 3dB points Beams touching at the 3dB*0.92 points

CSIRO. ASKAP Capabilities14 May 2009 Overall ASKAP System Beamfomer and Fine filterbank Antenna1 192fibre connection Beamfomer and Fine filterbank Antenna2 192fibre connection A/D and Coarse Filterbank Antenna36 Beamfomer and Fine filterbank Antenna Analogue inputs 192fibre connection Correlator Band1 Correlator Band2 Correlator Band16 Tied Array Post processing (VLBI and Pulsars) To Computing Centre Central Site at MRO Cross connect between beamformers and correlator Represents a single Advanced TCA chassis All Identical To Computing Centre To Computing Centre To VLBI network or pulsar processors A/Ds located in Antenna Pedestal A/D and Coarse Filterbank Antenna Analogue inputs A/D and Coarse Filterbank Antenna Analogue inputs

CSIRO. ASKAP Capabilities14 May 2009 Mode 1 imaging capabilities Continuum 1 channel + spectral index/curvature OR 256 spectral channels Full Stokes parameters (IQUV) 4k x 4k pixels (2km array) or 12k x 12k (6km array) Real-time source cataloguing Spectral Line channels (df=18kHz) 2 Stokes (I, V) 4k x 4k pixels (2km array) Visibilities not archived Limited number of cubes per day Slow transients snapshots : 16-channel, 4k x 4k pixel, 2 Stokes searched every 5 seconds selected images retained

CSIRO. ASKAP Capabilities14 May 2009 Modes 2+ Advanced imaging Will be driven by Survey Science Project Design Study ( ) e.g. “postage stamps”, full 30dB polarization dynamic range “ Zoom” modes 16k channels in 4~8 sub-bands, 0.6kHz(*2 n ) resolution, e.g.; HI MHz + ( MHz) VLBI – 2~3 tied-array beam voltages, recorded off-site frequency standard (H-maser vs Rb) Fast transients diverse requirements vs fluid capabilities active community consultation happening now

CSIRO. ASKAP Capabilities14 May 2009 Fast Transients – capabilities Flexible correlator – access to; single-dish autocorrelations, tied-array Voltages or Power, visibilities (optionally averaging) formed-beam voltages flexible user-determined averaging, nStok, nBit … some on-board capacity for processing, buffering Constraints on-site space, power limits & costs bandwidth to Geraldton (40Gb/s initially, shared) calibration (requires processing engine) FPGA programming effort (+testing, commissioning)

CSIRO. ASKAP Capabilities14 May 2009 The end