JWST ETC Pandeia GTO CANUCS NIRCam Imaging and the Python engine - PowerPoint PPT Presentation

JWST ETC Pandeia GTO CANUCS NIRCam Imaging and the Python engine Dan Coe ESA/AURA Astronomer II NIRCam Instrument Scientist Help Desk Lead JDox Deputy Lead Dan Coe – STScI 1

SNR Depends on Aperture Size r = 0.08” (2.5 pixels) r = 0.16” (2.5 pixels) photometric aperture annulus: annulus: sky annulus 0.6” – 0.99” 1.2” – 1.98” NIRCam 0.0317” short wavelength pixels r = 0.1” 0.0648” long wavelength pixels annulus: 0.22” – 0.4” Dan Coe – STScI 2

Selecting a NIRCam Readout Pattern MACSJ0416.1-2403 2019-11-30 F200W Default photometric apertures (r = 0.1”; sky annulus 0.22” – 0.4”) Dan Coe – STScI 3

Recommended Readout Patterns Dan Coe – STScI 4

5σ Depth from Interpolation 5 ~1 hour Dan Coe – STScI 5

Depth vs. Exposure Time Requires many loops and interpolations Background: Abell 370 (RA 02:39:50, Dec –01:35:08) 2019-08-30 (similar to Default: Medium RA=0 Dec=0) Short wavelength apertures: r = 0.08”; sky annulus 0.6” – 0.99” Long wavelength apertures: r = 0.16”; sky annulus 1.2” – 1.98” Dan Coe – STScI 6

JWST ETC Pandeia Python engine example: NIRCam Imaging https://github.com/dancoe/pandeia-imaging Dan Coe – STScI 7

Cluster galaxies will decrease signal-to-noise for high-redshift galaxies Dan Coe – STScI 8

Backgrounds Default is on the ecliptic Dan Coe – STScI 9

Backgrounds Similar to the default (RA 02:39:50, Dec –01:35:08) Dan Coe – STScI 10

Backgrounds Dan Coe – STScI 11

Backgrounds Dan Coe – STScI 12

Exposure times defined by readout patterns Dan Coe – STScI 13

Detector completes exposure 1 frame later Dan Coe – STScI 14

Consistent Exposure Times in APT 25.1 and ETC Example: 2 integrations, 3 groups, SHALLOW4 2 × (2 × 5 + 4 + 1) = 2 × 15 = 30 frame times = 322.1028 seconds (full detector) single frame time = 10.73676 s (ETC currently assumes 10.74 s → 322.2 total) Dan Coe – STScI 15

9 NIRCam Readout Modes M. Robberto Dan Coe – STScI 16

NIRCam Readout Modes are Familiar Times for full detectors (not subarrays) WFC3/IR first subsequent NIRCam first subsequent Readout group groups Readout group groups Mode (s) (s) Mode (s) (approx.) (s) (approx.) SPARS5 5 2.932 SPARS10 10 RAPID 10.7 2.932 10.7 SPARS25 25 BRIGHT 21.5 2.932 10.7 or 21.4 SPARS50 50 SHALLOW 53.7 2.932 21.5 or 42.9 SPARS100 100 MEDIUM 107.4 2.932 21.5 or 85.9 SPARS200 200 DEEP 214.7 2.932 21.5 or 85.9 Dan Coe – STScI 17