LSST+Euclid: galaxy shape measurement synergies Robert L. Schuhmann - PowerPoint PPT Presentation

LSST+Euclid: galaxy shape measurement synergies Robert L. Schuhmann (IfA Edinburgh, U Manchester) collaborators: Joe Zuntz, Catherine Heymans

image credit: LSST/NSF/AURA – ESA/C. Carreau LSST and Euclid

galaxy shapes: exploring synergies shape catalogue 0.1” pixels 0.2” pixels ● ● Gaussian PSF 0.06” Gaussian PSF 0.7” ● ● realistic CCD noise noise-free ● ● ( , ) J o i n t P i x e e 1 2 ( , ) J o i n t P i x δ δ e e 1 2 E u c l i d ( , ) C a t C o m b ( , ) e e ( , ) L S S T e e e e 1 2 1 2 1 2 E u c l i d ( δ , δ ) C a t C o m b ( δ , δ ) e e ( , ) L S S T δ δ e e e e 1 2 1 2 1 2 3

input catalogue 4

high-res limited-depth imaging (Euclid-like) 5

noise-free low-res imaging (LSST-like) 6

joint shapes: catalogue-level comb. 7

joint shapes: pixel-level comb. 8

relative comparison to Joint Pixel Analysis ∊ ( D – J o i n t P i x ) / J o i n t P i x f o r D { L S S T ; E u c l i d ; C a t C o m b } δ δ δ e e e 9

future work improvements in calibrating multiplicative bias ● simulating proper co-adding; more complex PSF models ● more galaxy profjles ● astrometry + PSF confusion ● blending!! ● … (your suggestion here!) ● 10

Thank you for your attention! … questions? 11