2 major components. Part 2: Imaging. Part 1: Enhancing the product. Parallelization (ASTRON) Calibration Transfer (JIVE) Wide Band Imaging (JBO)

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2 2 major components Part 1: Enhancing the product Calibration Transfer (JIVE) Antenna Gains Phase Cal Tones Ionospheric calibration (JIVE) Evaluate GPS Combine model, vertical structure Tropospheric calibration (MPI) Using GPS Water Vapor Radiometers Frequency extrapolation Post correlator processing (JIVE) Deal with PCInt data flow Multiple target selection Web portal, user interface Part 2: Imaging Parallelization (ASTRON) evaluation data reduction software research algorithms (MIRIAD) Wide Band Imaging (JBO) using parallel processing including self-cal may be frequency dependent Wide field Imaging (JIVE) using parallel processing including self-cal may be dominated by weak sources Some 4% from proposal scratched: e2e information handling Fringe fitting Infrastructure software (package) 2/12 Board meeting Jodrell Bank 13 Oct 24

3 First Year Activity JBO: wide band imaging: no action in year1 Starting recruitment postdoc shortly ASTRON: evaluation of parallelization, all in year1 Preliminary conclusions mid-term report MPI: tropospheric calibration, well underway Focus on WVR calibration, scientific evaluation Have hired programmer JIVE: calibration transfer & ionospheric calibration Two other work packages start in year2, same people Calibration transfer, initial milestones passed Largely the work of new software engineer Post-doc for ionospeheric program started 15 Nov All: work on user requirements (often slow) 3/12 Board meeting Jodrell Bank 13 Oct 24

4 Troposphere Focus on WVR at Effelsberg Installed radiometer on telescope Scanning 22GHz line in-beam Conversion to water vapour column Demonstrated to correlate with opacity Will be tested with VLBI data Software engineer started May 75% of full time Archive with web interface Data path into AIPS WVR project was moved forward Coming up next years GPS based Tropospheric calibration Dual-Frequency phase cal (eg, 15/43 GHz, 15/86 GHz) opacity.8.7 Comparison of Opacity Measured with 1 m RT and WVR, 24feb13 1 m RT RCP 1 m RT LCP WVR UT / hours 4/12 Board meeting Jodrell Bank 13 Oct 24

5 Calibration Transfer T sys into correlator product Also flagging and gain curves Implemented successfully Being evaluated for operations Aips++ code, principles known Gain Curve tables needed definition Optimized van Vleck corrections PhaseCal detection product Hardware available (in Mk4 SU) Brought to live First detections make sense Algorithms need to be evaluated Will be run on upcoming NME Could be finished in year1 (6/5) amplitude phase time (1s intervals) time (1s intervals) Effelsberg 4983 MHz, USB, RCP 4983 MHz, USB, LCP 4999 MHz, USB, RCP 4999 MHz, USB, LCP Effelsberg 4983 MHz, USB, RCP 4983 MHz, USB, LCP 4999 MHz, USB, RCP 4999 MHz, USB, LCP 5/12 Board meeting Jodrell Bank 13 Oct 24

6 Evaluation parallel software Evaluate parallel approaches for existing packages At ASTRON MIRIAD first choice for testing Close look at computational intensive parts (imaging) Preliminary results show possible improvements Use more modern routines for computational core Take advantage of vector architecture Compiler effectively uses multiple processors with shared memory Hard to use standard messaging protocols Typically used in large simulations Not suitable for data intensive operations Consider task parallelization, distribute data first Work focuses now on Python and Miriad Important for common software interface 6/12 Board meeting Jodrell Bank 13 Oct 24

7 Coding Platform Not a clear coding platform for user software Relatively easy when software behind curtains Applies for the early work at JIVE & MPI Hard when software has to run in user domain Very hard when it has to be scaled to cluster computing Desire to adopt a uniform approach So ALBUS can become visible, distributable, maintainable Nowhere in the world a clear solution Users want well-established AIPS algorithms Astronomer/programmer prefers maybe Miriad Depends critically on approach of parallel processing Outfit AIPS with Python scripting interface 7/12 Board meeting Jodrell Bank 13 Oct 24

8 AIPS/Python Would allow AIPS control from Python scripts Python: scripting language with lots of public libraries, including arithmetic, easy binding to compiled code, well structured for extensive programming Good solution for calibration tasks, prototyping, evaluation Possibly good for high-level, task parallelization Relevant for use outside ALBUS: pipelines, Grid, VO May merge with initiative on interoperability of packages Mid-sized project realistic in ALBUS time frame Some prototyping done by Bill Cotton Implementation in several stages Several points for of evaluation First stage allows calibration algorithm evaluation More involved for parallel processing And distribution of results to user Current status: proposal written, public, open for discussion May come back to board to redirect 1 2% of resources 8/12 Board meeting Jodrell Bank 13 Oct 24

9 Management & Reporting Started time-sheets Useful for internal management Did much less than full year s work Hardly any work before March Hiring specialists: 3 9 month delay Alternative spending profile hours Maybe not so relevant for FC model OK at most partners Worries about future matching Costs dominated by manpower Under-spending 3% - 7% Travel & meetings seem OK No hardware purchased total hours hours spending profile man-hours september-2 januari-4 mei-5 oktober-6 februari-8 date ALBUS hours 1/1-3/ JIVE staff JIVE hires MPI staff MPI hires ASTRON JBO staff JBO hires staff JIVE hires JIVE staff MPI hires MPI ASTRON null model realistic actual 9/12 Board meeting Jodrell Bank 13 Oct 24

10 25 8 ALBUS hours 1/1-3/9 24 spending profile man-hours 7 2 total hours hours JIVE staff JIVE hires MPI staff MPI hires ASTRON JBO staff JBO hires september-2 januari-4 mei-5 oktober-6 februari-8 staff JIVE hires JIVE staff MPI hires MPI ASTRON date null model realistic actual

11 Management & Reporting Started time-sheets Useful for internal management Did much less than full year s work Hardly any work before March Hiring specialists: 3 9 month delay Alternative spending profile hours Maybe not so relevant for FC model OK at most partners Worries about future matching Costs dominated by manpower Under-spending 3% - 7% Travel & meetings seem OK No hardware purchased total hours hours spending profile man-hours september-2 januari-4 mei-5 oktober-6 februari-8 date ALBUS hours 1/1-3/ JIVE staff JIVE hires MPI staff MPI hires ASTRON JBO staff JBO hires staff JIVE hires JIVE staff MPI hires MPI ASTRON null model realistic actual 11/12 Board meeting Jodrell Bank 13 Oct 24

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