The following pages contain information on the performance of Wide Field Camera 3 and its components.
Performance Information
Flight Detectors
UVIS
- Components: 2x2Kx4K thinned, backside illuminated, UV optimized e2v CCDs
- Wavelength Range: 200 to 1000 nm
- Total Field of View: 162 x 162 arcsec (rhomboidal)
- Pixel format: 2 butted 2051x4096, 31-pixel gap (1.2").
- Pixel Size: 15x15 microns
- Plate Scale: 0.04 arcsec/pixel
- Nominal Operating Temperature: -83C
- Dark Current: ~9 e-/hr/pix (median) [Revised May 2019. See WFC3 IHB, Table 5.1]
- Readnoise: 3.1 e-
- Full Well: 63,000 -- 72,000 e- [See WFC3 IHB, Table 5.1]
- Gain: 1.52 - 1.56 e-/ADU
- Instrument Throughput: UVIS filters
IR
- Components: 1Kx1K Teledyne HgCdTe FPA, MBE grown, substrate removed
- Wavelength Range: 800 to 1700 nm
- Total Field of View: 123 x 136 arcsec (rectangular)
- Pixel format: 1024x1024 (1014x1014 active)
- Pixel Size: 18 microns
- Plate Scale: 0.13 arcsec/pixel
- Nominal Operating Temperature: 145 K
- Dark Current: 0.048 e-/sec/pix (median) [See WFC3 IHB, Table 5.1]
- Readnoise: 21 e- (CDS), 12 e- (16-read linear fit) [See WFC3 IHB, Table 5.1]
- Full Well: 77,900 e- [See WFC3 IHB, Table 5.1]
- Gain: 2.5 e-/ADU
- Instrument Throughput: IR filters
Image Quality
- Image quality analysis of the IR channel shows ~85% of the flux for a point source falling within a radius of ~0.4 arcseconds when observed through the F110W filter. The encircled flux decreases with increasing wavelength to ~83% within a radius of ~0.4 arcseconds for a point source observed through the F160W filter. For more information on the IR detector encircled energy as a function of wavelength please see ISR 2009-37 and the IR Encircled Energy webpage.
- Image quality analysis of the UVIS channel shows ~87% of the flux for a point source falling within a radius of ~0.4 arcseconds when observed through the F275W filter. The encircled flux slightly increases with increasing wavelength to ~90% within a radius of ~0.4 arcseconds for a point source observed through the F814W filter. For more information on the UVIS detector encircled energy as a function of wavelength please see ISR 2022-02 and the UVIS Encircled Energy webpage.
We provide information regarding the point-spread function for the WFC3 detectors on the PSF webpage.
Both detectors experience anomalies that affect image quality. For more information, please see the Anomalies webpage.
Documentation
We provide a selection of recent and relevant Instrument Science Reports (ISRs) describing the image quality and photometric performance of the WFC3 detectors. For additional reports, please see the WFC3 ISR page.
IR
- ISR 2022-01: Cold and Unstable Pixels in WFC3/IR
- ISR 2021-10: WFC3/IR Blob Flats
- ISR 2021-05: Photometric Repeatability and Sensitivity Evolution of WFC3/IR
- ISR 2021-01: WFC3/IR Filter-Dependent Sky Flats
- ISR 2020-10: Updated WFC3/IR Photometric Calibration
- ISR 2009-37: WFC3 SMOV Programs 11437/9: IR On-orbit PSF Evaluation
UVIS
- ISR 2022-04: Monitoring WFC3/UVIS Photometric Sensitivity with Spatial Scans
- ISR 2022-02: WFC3/UVIS Encircled Energy
- ISR 2021-14: UVIS Pixel Stability: Updates to The UVIS Bad Pixel Table Pipeline
- ISR 2021-09: Updating the WFC3/UVIS CTE Model and Mitigation Strategies
- ISR 2021-04: New time-dependent WFC3 UVIS inverse sensitivities