search for high-redshift galaxies

Search for High-Redshift Galaxies

Wei Zheng

Johns Hopkins University

Granada

Power of CLASH Survey

• Data in about 300 square arcminutes: comparable to GOODS

• Data in about 100 square arcminutes in cluster fields: comparable to HUDF

• Accurate photometric redshifts and mass distribution maps enhance selection confidence

September 21, 2010

September 21, 2010

Faintness of High-Z Galaxies

Granada

Redshift 6 8 10m* ~ 26.5 ~27.8 ~29.2Number in UDF ~1000 ~30 ?

Spectroscopic capability of ground based telescopes: AB≈25Spectroscopic capability of JWST: AB≈27

GranadaSeptember 21, 2010

New Findings in A1703

HJzi

Granada

Goals

• Find more than 100 galaxies at z>7• Spectroscopic followup of bright candidates• Morphology of young galaxies• Complimentary study of the luminosity

distribution• Pathfinder for JWST studies of high-z galaxies

September 21, 2010

September 21, 2010

Cluster MACS J1149+22

Granada

Granada

Color Selection

September 21, 2010

Granada

Special Pipeline

• Detection Images from the reddest bandsF160W: z≈10.5F160W+F140W: z≈9F160W+F140W+F125W: z≈8F160W+F140W+F125W+F110W: z≈6.5

• Catalogs in each passband• Dropout catalog• Stamp images for inspection

September 21, 2010

Granada

Working Group

• Assignment: Adopt a cluster• Quick report within a week of data acquisition• Prompt publication within a month• Statistical studies at longer time scales

September 21, 2010

Granada

Test Runs

• Using published results:UDFA2218

• SED fitting• amplification map

September 21, 2010

Granada

Spectroscopic Followup

• VLT: X-shooter, SINFONI, ISSAC• Magellan: FIRE• GEMINI-N: GNIRS, FLAMINGO-2• Letter of intention to the director?

September 21, 2010

Granada

Summary

• CLASH provides an unprecedented opportunity for high-z search

• Selection procedures to be developed and tested

• Prompt publication is essential

September 21, 2010