The Square Kilometre Array: Overview and Engineering Update

The Square Kilometre Array is currently undergoing the Preliminary Design Reviews for its composing elements, and is thus at a critical point on its way to becoming ready for construction starting in 2018. In this talk we will provide an overview of the SKA, its composing elements, and their status, with emphasis on the Telescope Manager and the Science Data Processor, respectively the Monitoring & Control system, and Pipeline. We will see how do they compare with their ALMA equivalents, and how is the SKA similar/different from ALMA.

Seminar given on Dec 11, 2014, at the ALMA Headquarters in Vitacura, Chile.

Transcript

1. The Square Kilometre Array: Overview and Engineering Update ALMA SCO HQ, Dec 11 2014 Juande Santander-Vela
2. • Who am I? • SKA Science • Site, Telescopes, Technologies • SKA Organisation • Engineering Progress • SKA: the Exaflop HI Tomograph • ALMA vs. SKA: Telescope Control • What’s Next? Outline ALMA SCO HQ, Dec 11 2014
3. Who am I? ALMA SCO HQ, Dec 11 2014
4. • Systems Engineer for the SDP/TM elements (since March 2014) • VIA-SKA Project Manager (Jan ’12-Feb ’14) • Former VLT Archive Applied Scientist (Jun ’09- Feb ’11), ALMA Science Archive Front-/Back- end Developer at ESO Garching (Mar-Dec 2011) • Ph.D. in Radio Astronomical data archives & Virtual Observatory • Software Analyst/Manager in Industry Who am I? ALMA SCO HQ, Dec 11 2014
5. • Introduction • Science • Site, Telescopes, Technologies • SKA as an Exaflop Camera • Engineering Progress • What’s Next? Great observatories of the present… ALMA SCO HQ, Dec 11 2014
6. • Introduction • Science • Site, Telescopes, Technologies • SKA as an Exaflop Camera • Engineering Progress • What’s Next? …and the future ALMA SCO HQ, Dec 11 2014
7. • Introduction • Science • Site, Telescopes, Technologies • SKA as an Exaflop Camera • Engineering Progress • What’s Next? …and the future ALMA SCO HQ, Dec 11 2014
8. • Introduction • Science • Site, Telescopes, Technologies • SKA as an Exaflop Camera • Engineering Progress • What’s Next? …and the future ALMA SCO HQ, Dec 11 2014
9. SKA Science ALMA SCO HQ, Dec 11 2014
10. Fundamental Forces & Particles • Gravity • Radio pulsar tests of General Relativity • Gravitational Waves • Dark Energy • Magnetism • Origin and evolution of Cosmic Magnetism
 Origins • Galaxies and the Universe • Cosmic Dawn • First Galaxies • Galaxy Assembly & Evolution • Stars, Planets & Life • Protoplanetary Disks • Biomolecules • SETI Why we do this? SKA Science Goals ALMA SCO HQ, Dec 11 2014 XX Century: We discovered our place in the Universe XXI Century: We understand the Universe we inhabit Some of these can only be achieved with SKA2
11. • Initial SKA Science Book (2004): 5 KSPs, 43 additional ones • Updated SKA Science Book (2014): 13 Phase 1 Headline Projects, 130 Chapters • Projects reduced, parameterised from ~43 projects, through science prioritisation exercise with SKAO and SWGs SKA Science Goals ALMA SCO HQ, Dec 11 2014
12. • Astrobiology (“The Cradle of Life”) • Project Scientist: Tyler Bourke • WG Chair: Melvin Hoare • Galaxy Evolution – Continuum • Project Scientist: Jeff Wagg • WG Chairs: Nick Seymour & Isabella Prandoni • Cosmic Magnetism • Project Scientist: Jimi Green • WG Chairs: Melanie Johnston- Hollitt & Federica Govoni • Cosmology • Project Scientist: Jeff Wagg • WG Chair: Roy Maartens • Epoch of Reionisation & Cosmic Dawn • Project Scientist: Jeff Wagg • WG Chair: Leon Koopmans • Galaxy Evolution – HI • Project Scientist: Jimi Green • WG Chairs: Lister Staveley-Smith & Tom Osterloo • Pulsars (“Strong field tests of gravity”) • Project Scientist: Jimi Green • WG Chairs: Ben Stappers & Michael Kramer • Transients • Project Scientist: Tyler Bourke • WG Chairs: Rob Fender & J.-P. MacQuart SKA Science Goals: WGs ALMA SCO HQ, Dec 11 2014
13. SKA Science Goals: Headline Projects ALMA SCO HQ, Dec 11 2014 Year in the life of SKA1: Mock-up 3-years scheduling to constrain operations, computation
14. Telescopes, Sites, Technologies ALMA SCO HQ, Dec 11 2014
15. SKA Telescopes ALMA SCO HQ, Dec 11 2014 SKA1-Low
16. SKA Telescopes ALMA SCO HQ, Dec 11 2014 SKA1-Mid
17. SKA Telescopes ALMA SCO HQ, Dec 11 2014 SKA1-Survey
18. ALMA SCO HQ, Dec 11 2014 SKA1-Mid: Karoo Site
19. ALMA SCO HQ, Dec 11 2014 SKA1-Low/-Survey: Murchison Radio Observatory
20. SKA Organisation ALMA SCO HQ, Dec 11 2014
21. • Australia (DoI) • Canada (NRCZHIA) • China (MOST) • Germany (BMBF) • India (NCRA) • Italy (INAF) • Netherlands (NWO) • New Zealand (MED) • South Africa (DST) • Sweden (Chalmers) • UK (STFC) SKA Organisation ALMA SCO HQ, Dec 11 2014 Currently UK Company Limited by Guarantee → Treaty Organisation Other partners in negotiation, expected
22. SKA Governance: Pre-Construction ALMA SCO HQ, Dec 11 2014 * * * * * * * * * * * * * * * * * * SKA Governance Members$ Board$of$Directors$ $ SKA$Office$ ~50$staff$ $ Director;General$ 11$Design$ConsorXa$ ~500$ScienXsts$&$Engineers$ Strategy$&$$ Business$Dev$ Cmte$ Finance$ Cmte$ ExecuXve$Cmte$ Science$&$Eng$ Advisory$Cmte$ €23.4M$ (cash)$ ~$€125M$ (in;kind)$
23. SKA International Design Consortia ALMA SCO HQ, Dec 11 2014 Project Management and System Engineering Team based at JBO (UK) ~500 scientists & engineers in institutes & industry in 11 Member countries
24. Engineering Progress ALMA SCO HQ, Dec 11 2014
25. 64 x 13.5m offset Gregorian antennas 8km maximum baseline length First receivers: 0.9 – 1.67 GHz (L-band) 0.58 – 1 GHz (UHF) 770 MHz bandwidth Early operations 2016/7 SKA1 Precursors: MeerKAT ALMA SCO HQ, Dec 11 2014 First light with L-band receiver and digitiser erKAT
26. SKA1 Precursors: MeerKAT ALMA SCO HQ, Dec 11 2014 Lot’s more of infrastructure already in place: dish assembly shed; bunkered and RFI shielded data processor room and power system
27. SKA1 Precursors: MeerKAT ALMA SCO HQ, Dec 11 2014 Lot’s more of infrastructure already in place: dish assembly shed; bunkered and RFI shielded data processor room and power system
28. SKA1 Precursors: ASKAP ALMA SCO HQ, Dec 11 2014 36 x 12m antennas 3-axis movement 30m – 6km baselines Novel PAF receiver 700MHz – 1800MHz Wide field of view Fast survey speed
29. BETA • 6 Mk I PAFs and digital systems • Commissioning, learning about beamforming 
 Lesson: deploy early, test, ensure adequate gap to production commitment ASKAP • First Mk II PAF installed • Results expected in next few weeks • Production of Mk II PAFs install through to Feb 2016 SKA1 Precursors: ASKAP ALMA SCO HQ, Dec 11 2014
30. SKA1 Precursors: MWA ALMA SCO HQ, Dec 11 2014 Murchison Widefield Array, Operational 17 refereed papers published, more coming
31. 3 dish prototypes in testing ALMA SCO HQ, Dec 11 2014
32. SKA: the Exaflop HI Tomograph ALMA SCO HQ, Dec 11 2014
33. • Dishes, feeds, receivers (N=250 → 2500) • Low and mid aperture arrays (n=250k → 1000k) • Signal transport (~1 Pb/s → 10 Pb/s) • Signal processing (exa-MACs) • Software engineering & algorithm development • High performance computing (exa-flop capability) • Data storage (exa-byte capacity) • (Distributed) power requirements (10 → 50MW) Engineering Challenges ALMA SCO HQ, Dec 11 2014
34. SKA High-Level Architecture ALMA SCO HQ, Dec 11 2014 SKA-TEL-SKO-DD-001 Revision : 1 Figure 1 A schematic diagram of the SKA Observatory, showing the geographical locations of site entities (telescopes), the entities at regional centres (Host Country Headquarters and Science Data Processing), and Regional Science & Engineering Centre(s) Regional Science & Engineering Centre(s) SKA Observatory Global Headquarters Remote stations on spiral arms Science Computing Remote Station Remote Station Remote Station Host Country Headquarters Central Signal Processing SKA1-low SKA1-survey Core Arrays Australia Remote stations on spiral arms Science Computing Remote Station Remote Station Remote Station Host Country Headquarters Central Signal Processing Mid-Freq Aperture Array (SKA2) SKA1-mid Core Arrays South Africa
35. SKA Elements & Interfaces ALMA SCO HQ, Dec 11 2014 INFRA DSH LFAA CSP SDP TM Command control flow Data flow SaDT Timing Conceptual figure: it should be split by telescope
36. SKA Elements & Interfaces ALMA SCO HQ, Dec 11 2014 INFRA DSH/LFAA CSP SDP TM Command control flow Data flow SaDT Timing Conceptual figure: it should be split by telescope
37. • Software Defined Networking • Allows easy partitioning, sub-arraying, quality of service, commensality… • Software Defined Beamforming (-Low, - Survey) • Software Defined Computing • Data-Flow Driven Science Data Processing SKA is a Software-Defined Telescope ALMA SCO HQ, Dec 11 2014 Lots of computing challenges
38. ALMA SCO HQ, Dec 11 2014 Science Data Processor Local M&C Science Data Processor Telescope Manager Correlator / Beamformer Data Routing Ingest Visibility processing Multiple Reads Time Series Search Multiple Reads Data$Buffer Data Routing Time Series Processing Image Plane Processing Data Prodcuts Sky Models, Calibration Parameters ... Meta Data Master Controller Master Controller Local M&C Database Tiered Data Delivery
39. ALMA SCO HQ, Dec 11 2014 Performance Modelling •  Imaging and calibration determines system sizing •  Data is Buffered after Ingest •  Detailed analysis building on Cornwell: •  Imaging o  AW-projection o  Plus w-snapshots o  Plus faceting (working memory size) •  Continuum imaging always required for calibration o  Field of view to second zero of beam •  Maximal case includes “science discovery” mode of forming high spectral-resolution image cube over primary beam •  Commensal fast-imaging mode for slow transients Processing maximal (Pflop) Ingest (GB/s) Use Case examples (GB/s) LFAA! 100! 7300! 245! Survey! 135! 4600! 995! Mid! 360! 3300! 255! Detailed analysis is much more complicated courtesy
40. SKA1 Archive Size ALMA SCO HQ, Dec 11 2014
41. ALMA vs. SKA: Telescope Control ALMA SCO HQ, Dec 11 2014
42. • Need to find COTS-based solution • Move away from expensive hard real-time solutions • Switched network inside products • Orchestration instead of deterministic control • Certain amount of product independence SKA Control Problem ALMA SCO HQ, Dec 11 2014
43. SKA Elements & Interfaces ALMA SCO HQ, Dec 11 2014 INFRA DSH LFAA CSP SDP TM Command control flow Data flow SaDT Timing Conceptual figure: it should be split by telescope
44. ALMA SCO HQ, Dec 11 2014 Figure 1. ALMA Software Subsystems interaction diagram (source: ALMA Software documentation) CSP SDP SDP.PIP.* SDP.PIP.* TM.OBSMGT TM.TELMGT SDP.INGEST
45. ALMA SCO HQ, Dec 11 2014 TM.TELMGT TM.OBSMGT DSH.LMC CSP.LMC SDP.INGEST SDP.PIP.* SDP.ARCH SDP.LMC Commands Data Monitoring/Status CSP.CORR DSH.RECEIVER SKA Observation interaction: SKA1-Mid
46. ALMA SCO HQ, Dec 11 2014 Ethernet switching Middleware TBD (EPICS/TANGO/OPC UA) DSH.LMC SADT.DDBH SADT.TM CSP.LMC SADT.SAT
47. ALMA SCO HQ, Dec 11 2014 TM.TELMGT TM.OBSMGT TM.TELMOD SDP.PIP.
48. What’s next? ALMA SCO HQ, Dec 11 2014
49. 2016 2015 2017 2018 2019 2020 2021 2022 2023 2014 High/level/design Rebaselining/submissions/(RBS) Preliminary/Design/Review/(elements) Detailed/design Prototype/systems/deployed Critical/Design/Review SKA1/construction/approved Procurement SKA1/early/science SKA1/construction SKA2/detailed/design Design/consortia/start SKA2/procurement SKA2/construction/starts SKA2/concept/development Board/RBS/approval 3K5/Mar/15 15K22/Sep/14 1/Nov/13 PreKconstruction/Stage/1 PreKconstruction/Stage/2 Production*Readiness*Review*(4*dish*array) Construction*Readiness*Review* (1*dish*line9up) New/SKA/Organisation/in/place Key/Doc/Set/&/Prospectus Formal/negotiations Ratification/of/Agreements Organisation/has/minimum/no./Members/with/Agreements/ratified Agreements/in/Key/Doc/Set/signed Andrea/Casson,/SKAO/Project/Controller,/Sept/2014 System/PDR Integration/testing/on/site Advanced/Instrumentation/Prog. KEY:/Blue/=/SKA1/science/&/engineering;/orange/=/policy;/green/=/SKA2;/milestones*in*italics*=/proposals/under/discussion The SKA1 timeline
50. The SKA1 timeline ALMA SCO HQ, Dec 11 2014 Issue%Baseline% Design Science% Assessment% Workshops Proposal% Feedback Level%1% Requirements% Feedback Science% Conference Engineering% Meeting Engineering%Change%Proposals Designs%&% Costs SKAO%Review Technical% Advice (working% groups) SEAC Board Consortium%Design%Activities Level%0% Requirements Brief% SEAC 2013 2015 Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar 2014 PDR Science Review%Panel Science Review% Panel !! !! !! !! !! !! !!(43) !! !! !! !! Issue%Baseline% Design Science% Assessment% Workshops Proposal% Feedback Level%1% Requirements% Feedback Science% Conference Engineering% Meeting Engineering%Change%Proposals Designs%&% Costs SKAO%Review Technical% Advice (working% groups) SEAC Board Consortium%Design%Activities Level%0% Requirements Brief% SEAC 2013 2015 Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar 2014 PDR Science Review%Panel Science Review% Panel
51. Questions? Juande Santander-Vela j.santander-vela@skatelescope.org