1CORE DATA PROCESSING SOFTWARE PLAN REVIEW | SEATTLE, WA | SEPTEMBER 19-20, 2013Name of Meeting • Location • Date - Change in Slide Master

Data Release Processing (Level 2) Overview

Mario JuricLSST Data Management Project Scientist

September 19-20, 2013

CDP FINAL DESIGN REVIEWSeptember 19 - 20, 2013

2CORE DATA PROCESSING SOFTWARE PLAN REVIEW | SEATTLE, WA | SEPTEMBER 19-20, 2013

Level 2 Data Releases

− Well calibrated, consistently processed, catalogs and images• Catalogs of objects, detections, detections in difference images, etc.

− Made available in Data Releases• Annually, except in Year 1

- Two DRs in the first year

− Complete reprocessing of all data, for each release• Every DR will reprocess all data taken up to the beginning of that DR

− Accessing the catalogs• Database and Science User Interface (web based)• Remote access APIs, VO protocols (e.g., Table Access Protocol)

3CORE DATA PROCESSING SOFTWARE PLAN REVIEW | SEATTLE, WA | SEPTEMBER 19-20, 2013

Key Data Products

− Processed visits (“calibrated exposures”)• Visit images with instrumental signature removed, background, zero-point and

WCS determined− Coadds

• Deep coadds across the entire survey footprint

− Catalogs of Sources (a.k.a. Detections)• Measurements of sources detected on calibrated exposures

− Catalogs of Objects• Characterization of objects detected on multi-epoch data

− Catalogs of ForcedSources• Forced photometry performed on all exposures, at locations of all Objects

More in DPDD Section 5.4

More in DPDD Section 5.3

4CORE DATA PROCESSING SOFTWARE PLAN REVIEW | SEATTLE, WA | SEPTEMBER 19-20, 2013FINAL DESIGN REVIEW | TUCSON, AZ | OCTOBER 21-25, 2013

Data Release Processing (DRP) Physical Diagram

5CORE DATA PROCESSING SOFTWARE PLAN REVIEW | SEATTLE, WA | SEPTEMBER 19-20, 2013

Level 2 Processing

DRP begins with processing, detection, and measurement on single frames, generating Sources.

These are used to photometrically and astrometrically calibrate the survey.

A series of coadds is built next, where Objects are detected.

Detections on co-adds are deblended and associated to form a master object list.

The objects are simultaneously characterized in all observed epochs (MultiFit).

Time variability is characterized by independent measurement of Forced Sources in individual epochs.

6CORE DATA PROCESSING SOFTWARE PLAN REVIEW | SEATTLE, WA | SEPTEMBER 19-20, 2013

Level 2 Talk Roadmap

− The talks to follow will cover key steps in data release production process• Krughoff, Lupton: Single frame processing and measurement• AlSayadd: Generation of coadds• Lupton: Detection, association, and deblending• Bosch: Object characterization

− We will not discuss global self-calibration (reviewed separately)

− For time and clarity, we have emphasized and provided expanded discussion on the components and algorithms considered most complex, novel, or those that carry the biggest risk. We are happy to discuss others if the committee wishes to do so (e.g., forced photometry).

7CORE DATA PROCESSING SOFTWARE PLAN REVIEW | SEATTLE, WA | SEPTEMBER 19-20, 2013