Data Pipeline

Wei Zheng

Johns Hopkins University

Granada

Requirements

• Science images for ACS/WFC, WFC3/UVIS and WFC3/IR

• Detection image over all bands• Filter Images with a common WCS grid• Source catalogs• Photometric redshift catalogs

September 20, 2010

Granada

APSIS

• Image registration • Sky subtraction• Distortion correction• Cosmic ray rejection• Edge mask• Astrometric correction• Detection image

September 20, 2010

• Extinction correction• Extractor source

catalogs• Multicolor catalog• BPZ catalog

Granada

Modification

• ACEX: ACS image drizzling• WFEX: WFC3 image (UVIS and IR) drizzling• DREX: Register images of different passbands

September 20, 2010

Check data on CLASH central storage via fast-track ftp No

All data present?

Flowchart

Yes WFC3 or ACS? Run ACEX

Run WFEX

ACS

WFC3

Run ACEX

Run WFEX

Image Align

Image Combine

.felt files

Image Align

Image Combine

Run DREX

(0.065”)

Master Detection

Image

Co-added images in

native resolution

Extractor

Source Catalogs in

each passband

Multi-color catalog

PHOTO-Z Code(s)

Co-added images on

common pixel grid

PHOTO-Z Catalog

CLASH Science Team Data Archive

Granada

Astrometric Accuracy

September 20, 2010

WFEX WFC3RED

Granada

Pipeline Output: Images

• Detection Image (0.065” scale)• Combined images in each band (0.065” scale)• Combined UVIS and WFC images in original

scale

September 20, 2010

Granada

Pipeline Output: Catalogs

• Running Sextractor• Source catalogs in each band• Multicolor catalog• Photometric redshifts • Mag_iso, mag_auto, and mag_aper at various

sizes.

September 20, 2010

Granada

Processing Plan

• One run for every visit• Accumulated data for each version• Typically eight versions of processed data per

cluster• The final version has the best quality

September 20, 2010

Granada

Further improvements

• Slight alignment on drizzled images• Flag and mask consolidation• CTE correction for ACS• Data server

September 20, 2010

Granada

Summary

• A working pipeline • Need more in-depth comparisons and quality

checks• Need to accommodate new science

requirements

September 20, 2010

Granada

Many Thanks!

• Amit Saraff• John Blakeslee, Larry Bradley• Warren Hack, Andy Fruchter

September 20, 2010