S.A. Torchinsky SKADS Workshop 10 October 2007 Simulations: The Loop from Science to Engineering and back S.A. Torchinsky SKADS Project Scientist

S.A. Torchinsky SKADS Workshop 10 October 2007 SKADS Science Simulations ? In the context of technological constraints

S.A. Torchinsky SKADS Workshop 10 October : Key Science Pune meeting: Key Science agreed –Large Scale Structure (HI galaxy survey) –Epoch of Reionisation –Cosmic Magnetism –Tests of General Relativity in extreme fields (Pulsars) –Cradle of Life (protoplanetary disks, planets, organic molecules)

S.A. Torchinsky SKADS Workshop 10 October 2007 SKA Science Book

S.A. Torchinsky SKADS Workshop 10 October 2007 Strong Field Tests of Gravity Binary orbit permits determination of masses Relativistic effects permit (re) determination of masses. ALL MUST AGREE

S.A. Torchinsky SKADS Workshop 10 October 2007 Strong Field Tests of Gravity Large surveys will find exotic binarys –~ pulsars in the galaxy –Nearly edge-on Pulsar – Black-hole binary (at least one) Probe eg. Frame dragging, no-hair theorem, cosmic censorship Pulsar timing array –Gravitational wave background

S.A. Torchinsky SKADS Workshop 10 October 2007 Probing the Dark Ages When did the first luminous objects form? How did they form and over what period of time? SKA will detect the Epoch of Reionisation and map the evolution history of the first luminous objects Furlanetto

S.A. Torchinsky SKADS Workshop 10 October 2007 Local hydrogen Hydrogen in a distant galaxy Large Scale Structure Billions of galaxies!

S.A. Torchinsky SKADS Workshop 10 October 2007 BAO and Dark Energy Improve signal confidence by measuring wiggles in separate redshift bins Blake et al 2004: example assuming w=-0.8, peaks don’t line up with CMB peaks (vertical lines)

S.A. Torchinsky SKADS Workshop 10 October 2007 Cosmic Shear Integrated gravitational lensing along line-of-sight –“weak lensing” Requires large statistics –SKA continuum survey of 10 Billion galaxies –Clean sample Reject star burst galaxies which may be the result of mergers (morphological alignment not the result of cosmic shear) Still have a large sample with SKA –Improve result with analysis in redshift bins Redshifts from SKA HI survey

S.A. Torchinsky SKADS Workshop 10 October 2007 Cosmic Magnetism Origin of magnetic fields –Dynamo? –Primordial?

S.A. Torchinsky SKADS Workshop 10 October 2007 Cradle of Life Protoplanetary disks resolved to Earth-like orbits Organic molecules Extrasolar planets Extra terrestrial intelligence

S.A. Torchinsky SKADS Workshop 10 October 2007 Key Projects plus two ? transients the unknown

S.A. Torchinsky SKADS Workshop 10 October 2007 Transient signal

S.A. Torchinsky SKADS Workshop 10 October 2007 Transients Pulsar is a special case of transient phenomena (periodic) Giant pulses Supernova Bursters ETI requires: fast time constant memory buffer for post analysis wide instantaneous, fully-sampled FoV

S.A. Torchinsky SKADS Workshop 10 October 2007 The Unknown New discoveries always result from observations in new parameter space –sensitivity –spatial resolution –spectral resolution –polarisation –time domain –observing speed (multibeaming) eg. CMB, pulsars, extra solar planets,… SKA improves all of these SKA is designed for the Key Projects but with an overriding design philosophy of flexibility to maximise the likelihood of new discoveries

S.A. Torchinsky SKADS Workshop 10 October 2007 SKADS Science Interactions The Universe Our understanding of the Universe Sky Simulation (DS2T1) Convolution with the telescope (DS2T2) Network simulator (DS3T3) Technology development (DS4) Technology demonstrators (DS5 & DS6) observations brain power Catalogs, images, EM fields voltages measurements and simulated performance Request spec change BENCHMARK Backend data Data imaging (DS2T2) Simulated telescope image Data analysis (DS2) science goals achievable?

S.A. Torchinsky SKADS Workshop 10 October 2007 SKADS Science Interactions The Universe Our understanding of the Universe Sky Simulation (DS2T1) Convolution with the telescope (DS2T2) Network simulator (DS3T3) Technology development (DS4) Technology demonstrators (DS5 & DS6) observations brain power voltages measurements and simulated performance Backend data Data imaging (DS2T2) Simulated telescope image Request spec change BENCHMARK Catalogs, images, EM fields Data analysis (DS2) science goals achievable? Consider trade-offs NO: not technologically feasible NO: too expensive YES: We can do better than that ! SKADS Design & Costing

S.A. Torchinsky SKADS Workshop 10 October 2007 SKADS Science Simulations Pure sky simulations (DS2T1) feed back into telescope simulations, configuration studies, (DS2T2) and costing (DS3) Key projects drive technical requirements, e.g. –Field of view (mapping speed) –Total Frequency range –Instantaneous bandwidth –Spectral resolution –Angular resolution –Sensitivity (A eff /T sys )

S.A. Torchinsky SKADS Workshop 10 October 2007 Simulations in Publications

S.A. Torchinsky SKADS Workshop 10 October 2007 Simulations for the SKA Proceedings of the meeting held at Pushchino Radio Astronomy Observatory, Russia 30 July – 1 August 2007 edited by S.A. Torchinsky

S.A. Torchinsky SKADS Workshop 10 October 2007 Pushchino Meeting Simulations for the SKA 30 July to 1 August in Pushchino, Russia ~30 participants Proceedings (nearly) produced –Currently 62 pages, waiting for the last few contributions

S.A. Torchinsky SKADS Workshop 10 October 2007 Pushchino Proceedings (1/3)

S.A. Torchinsky SKADS Workshop 10 October 2007 Pushchino Proceedings (2/3)

S.A. Torchinsky SKADS Workshop 10 October 2007 Pushchino Proceedings (3/3)

S.A. Torchinsky SKADS Workshop 10 October 2007 Science Involvement in EMBRACE Test and evaluation of EMBRACE

S.A. Torchinsky SKADS Workshop 10 October 2007 DS5T3 Evaluation of EMBRACE Demonstrate that EMBRACE can be used for astronomical observations –Pulsar timing –Multibeam pulsar timing –HI mapping –Continuum mapping –Source tracking –Observations in the presence of strong sources (moon, sun) –Correlation with long baseline (Westerbork – Nançay) –Engineering/characterisation testing Beam profile, Tsys, Aeff, etc, Opportunity to have first-hand experience using AA for astronomy Head-start for exploiting SKA

S.A. Torchinsky SKADS Workshop 10 October 2007 SKADS Science Simulations ? In the context of technological constraints

S.A. Torchinsky SKADS Workshop 10 October 2007 SKADS Webpage