Introduction to EVLA Software

1. Introduction to EVLA Software Bryan Butler

2. EVLA Computing (Terse) History • The original EVLA Phase I proposal had only M&C software under direct project control (budgeted), other software was to be “supplied” by the DM Division. • After dissolution of the DM Division, the EVLA project took responsibility for all software elements (though post-processing was still somewhat separate in the CASA group). Some project contingency was redirected to support new staff in previously unfunded areas (SSS). • New e2e Operations Division will now take responsibility for some common elements (Portal, PST, AAT, Pipelines, post-processing). EVLA M&C Transition Software CDR

3. EVLA Computing Organization EVLA M&C Transition Software CDR

4. EVLA High Level Design • Most major subsystems have a direct counterpart in current VLA software • We have a significant amount of experience in what is needed for those subsystems • Electronic storage and passage of information between subsystems, and therefore the ability to do much of this automatically, is the new part • Subsystems are loosely coupled; information (the models) is stored in databases and accessed independently by the subsystems, or passed via queries EVLA M&C Transition Software CDR

5. EVLA High Level Design DATAFLOW EVLA M&C Transition Software CDR

6. EVLA High Level Design (1) Proposal Submission Tool (PST) Proposal Portal Proposal Handling Tool (PHT) Astronomer or Staff Authenticated Astronomer or Staff EVLA Observing Heuristics Project Observation Preparation Tool (OPT) Program Block (Set of Scheduling Blocks for one Program) To Observation Scheduling Tool EVLA M&C Transition Software CDR

7. EVLA High Level Design (2) From OPT Archive Observation Scheduling Tool (OST) Operator Environment Heuristics Metadata to DCAF Execution State Next SB Archive Executor Operator Metadata to DCAF Results from TelCal Equipment State Sequence of Configurations Antenna Delays From AMCS & CMCS To AMCS & CMCS EVLA M&C Transition Software CDR

8. EVLA High Level Design (3) From Executor State Counts FOTS Receiver Station, Baseline Boards EVLA Antennas RF CBE Lag Frames AMCS FF Raw Vis CMCS Hardware M&C Equipment State, Data Addressing Info, Messages, Alerts, etc. To Archive & TelCal To DCAF To DCAF EVLA M&C Transition Software CDR

9. EVLA High Level Design (4) Astronomer or Operator To Executor And Archive From AMCS & CMCS From CMCS Portal TelCal Results Data Capture And Format (DCAF) TelCal Authenticated Astronomer or Operator SDM SDM M&C Archive Observation Monitoring Tool (OMT) Quick Look Pipeline (QLP) M&C Archive To Archive (?) To Archive EVLA M&C Transition Software CDR

10. Archive EVLA High Level Design (5) Astronomer From DCAF From CMCS Open Products Archive Access Tool (AAT) Portal Cubes (?) Existing Proprietary Products Image Cubes Open Products Data Post-Processing (DPP) Default Image Pipeline (DIP) Trigger Authenticated Astronomer VO Astronomer Reprocessed Proprietary Products EVLA M&C Transition Software CDR

11. Major Elements (“Models”) The main flow of information (and processes; the “workflow” or “dataflow”) is: A Scheduling Block (SB) is an atomic unit of observing. It is made up of a sequence ofscans; a scan is made up of source(s), resource(s) (hardware definition - both Front End and Back End), timinginformation, and a “mode”. The mode defines the subscan(s), which are comprised of a single source, resource, and timing information. Proposal Data Project(s) Commands Program(s) Schedule(s) EVLA M&C Transition Software CDR

12. Timescale and Major Releases Now EVLA M&C Transition Software CDR

13. Transition Software • The Phase I proposal stated that the VLA would continue to operate during EVLA construction: “A key goal for the implementation of the Ultrasensitive Array is to impact as little as possible the scientific viability of the VLA”. • Our Visiting and Users Committees have reinforced this point strongly - if the VLA has significant down time (years), we run the risk of shutting off the supply of young astronomers interested in using the EVLA. • We therefore need software to operate the combined VLA/EVLA instrument during this transition period, with various combinations of hardware from both. • As a side note, we use the transition system software as a testbed for the final EVLA system - as prototypes from which we learn EVLA M&C Transition Software CDR

14. Transition Software Broad Requirements • The EVLA Monitor and Control system must support simultaneous operation of the old VLA antennas and the EVLA antennas during the transition phase, using the VLA correlator (note that there is no requirement to incorporate VLA antennas into observations using WIDAR) • Array down time shall be minimized as much as possible during the transition phase, • Transition operations using any part of the VLA shall be possible using VLA OBSERVE files (to maintain backward compatibility with VLA antennas while they exist) • From a software resource perspective, transition-specific software (throw-away) code must be minimized EVLA M&C Transition Software CDR

15. Transition Software Crude Schedule • Support for EVLA antenna hardware development • Participation of EVLA antennas in VLA scientific observations • The monitor and control of VLA antennas by the EVLA Monitor and Control System • The monitor and control of the VLA correlator by the EVLA Monitor and Control System, coupled with the distribution of VLA correlator output within the EVLA Monitor and Control System • The formation and writing of VLA format archive records by the EVLA Monitor and Control System • A period of parallel operation and testing EVLA M&C Transition Software CDR