PDR Studies for the VLASS -------------------------------------------------------------------------- S. Myers 2015-11-13 (Last Revised 2015-12-21) There are a number of pre-ops items identified in the VLASS SOW as deliverables for the PDR and CDR. I propose that these and other work needed for the DRs be organized as a series of "Studies" that will be written by NRAO and the SSG and presented to the PDR panel and also posted to the community (e.g. as memos). Below is an initial list of studies, which can be modifed or augmented as needed. Pre-ops items can be assigned to the studies in the next stage of preparation. Principal authors should be assigned to each document (suggestions of leaders and participants are given). The sub-item in each Study given below are merely suggestive of possible contents. Note that some topic are linked to more than one study, one study can refer the other in that case (there should be a principal study assigned to each deliverable). This is a fairly long list (currently a "lucky 13") but I think it needs to be to allow it to be broken down so parts can be led by the appropriate persons. I envision that there would be PDR and CDR versions for each Study, appropriately scoped. 1. Pilot Survey Study (SSG/Chandler/Myers) - given boundary constraints (total time, LST range, dates), design the Pilot Survey - identify target regions of sky - plan observations, sessions (e.g. 1 week early plus 1 week at end) - data products (BDP & EDP) from Pilot and timescales for delivery - opportunities and plans for community involvement (students, post-docs, NSF proposals, outreach) 2. EPO Study (NRAO-EPO/SSG) - outline of staged EPO plan from pre-Pilot, through Pilot, into main survey observing and ops phase - investigation of technologies and methods for EPO communication (wiki, forum, blogs, podcasts, social media, press releases,...) - identification of personnel to be involved (inside and outside the VLASS) and roles - data products from the survey and Pilot needed for EPO - educational resources generated by VLASS - involvement of students and postdocs in VLASS, mentoring 3. Enhanced Data Product Study (SSG/Lacy/Clarke/Chandler/Myers) - lists of needed and suggested EDP - for each EDP estimate expertise and resources needed - plan for community call and engagement - identified community resources and leaders for EDP - requirements on NRAO for enabling EDP - VLITE interface - other links for EDP (LWA,LOFAR,Pan-STARRs,LSST,etc.) - EDP for EPO? 4. OTFM Study (Myers/Mooley/NRAO-SCI/Law) - description of OTFM - evaluation of antenna performance - design and requirements for OPT for OTFM - calibration and imaging performance of OTFM using CASA - test results for all of above 5. Scheduling and Operations Study (Chandler/NRAO-OPS/Myers) - definition of sky tiles for VLASS - schedule preparation - schedule submission and monitoring - schedulability (HA range, time of day, etc.) - use of hybrid vs. Declination - assessment of x2 rate at x2 HA on scheduling - early QA (QA1) - calibrator database requirements and use - calibration (array) parameter database - interactions with Calibration and Quick-Look pipelines - status reporting and logging - external interrupt response and recovery - just-in-time schedule generation? - triggered calibration (leakage, bandpass, etc.) - staffing - risk assessment and mitigation 6. Archive and Basic Data Products Study (NRAO-DMS/NRAO-SCI/Lacy/SSG) - overview of Data Products for VLASS (Pilot and Main Survey) - definition of each BDP - archiving and serving requirements - database for VLASS observations and products - interface to EDP - staffing - risk assessment and mitigation 7. Pipeline Processing Architecture Study (NRAO-DMS/NRAO-OPS/NRAO-SCI) - overview of pipelines - pipeline interfaces (operator, science, archive) - status and limitations of current pipeline implementations - technology assessment and development plan - computing resources and requirements - performance goals and evaluation (flag/cal/imaging/analysis) - Process On Demand (POD) investigation and plans - staffing for pipeline development and maintenance - risk assessment and mitigation 8. Performance, RFI, and Flagging Study (NRAO-SCI/Law/Myers/NRAO-DMS/LOFAR?) - S-Band RFI environment assessment, results of tests - assessment of rms sensitivity (RFI losses, sens. vs EL) - overview of RFI flagging algorithms and implementations - exploration of methods in CASA and elsewhere (tfcrop,rflag,aoflagger) - testing and results on VLASS (and other) test data - interface to pipeline(s) - QA reporting from flagging - efficiency and processing requirements - further and ongoing development - staffing - risk assessment and mitigation 9. Calibration Study (NRAO-SCI/NRAO-OPS/NRAO-DMS) - overview of Calibration pipeline and interface to ops - calibration algorithm and implementation overview - QA2 plans and requirements - calibrator database interface and maintenance - array calibration database (antpos,gaincurve,other?) - link to auto-flagging interfaces - link to imaging/self-cal - interface to archive - use of built-in cal obs or triggered (leakage,bandpass,etc.) - staffing for CalPipeline - risk assessment and mitigation 10. Imaging Study (Myers/NRAO-DMS/NRAO-SCI) - overview of imaging pipelines - imaging quality requirements - assessment of x2 rate at x2 HA on image quality - assessment of hybrid (BnA) use vs. declination - assessment of effects from variable (compact) sources on imaging - assessment of rms sensitivity as a function of angular scale - assessment of current imaging performance and processing needs - algorithm and implementation overview and exploration - quick-look pipeline definition and requirements - single-epoch pipeline definition and requirements - cumulative pipeline definition and requirements (e.g. as augmentation to SE pipeline) - extended source sensitivity and tapered image production - autoboxing algorithms and implementation - metrics for image fidelity and QA - operator interface and QA3 - interface to archive - test data and test plan - imaging software performance results and evaluation - ongoing development plan - EPO interfaces - use of POD for imaging - risk assessment and mitigation 11. Catalog and Analysis Study (Lacy/NRAO-SCI/Law/Myers/NRAO-OPS) - overview of source-finding and catalog products needed - source-finding for QL/SE/CI pipeline products - definition of quantities needed from source finder/measurement - assessment of source-finders and image fitters - requirements on imaging pipelines - fault tolerance and assessment - interface to archive and alert generators (transients, queries) - object IDs (multi-wavelength) as BDP or EDP - large image viewing options - ongoing development plan - staffing - risk assessment and mitigation 12. Transient Science Study (SSG/Myers/NRAO-SCI) - overview of VLASS Transient Science (Hidden Explosions) goals - BDP requirements - calibration requirements - requirements on survey design (Pilot and Main survey) - requirements on the Quick-Look (QL) pipeline and analysis - requirements for QL catalogs - need for / incorporation of polarization for QL - need for spectral information at QL stage? - QA requirements and fault tolerance - object IDs (multi-wavelength) - external event response and interrupts - commensal fast-transients - EDP opportunities and plans - national and international involvement and resources - EPO interfaces (public,community,students) - staffing and community recruitment - risk assessment and mitigation 13. Polarization Science Study (SSG/NRAO-SCI/Myers) - overview of VLASS Polarization Science (Faraday Tomography) goals - BDP requirements (continuum images, coarse spectral cubes, fine spectral cubes) - requirements on survey design (Pilot and Main survey) - requirements on the Calibration pipeline - requirements on the Single-Epoch (SE) and Cumulative Image (CI) pipelines - assessment of polarization imaging algorithms (IQUV cubes, Faraday Synthesis Imaging) - assessment of polarization analysis algorithms (IQUV fitting, FR Synthesis) - assessment of effects of variable sources and mitigation - processing requirements - archiving requirements and data serving - EDP opportunities and plans - national and international involvement and resources - EPO interfaces (public,community,students) - use of POD for polarization - staffing and community recruitment - risk assessment and mitigation NRAO Groups: ------------ NRAO-DMS = Data Management and Software NRAO-EPO = Education and Public Outreach NRAO-OPS = Operations NRAO-SCI = Science Support (including data analysts) Chandler = VLASS Director (Claire Chandler) Lacy = VLASS Project Scientist (Mark Lacy) Myers = VLASS Technical Lead (Steve Myers)