Roman Space Telescope (WFIRST) Instrument Reference Information (Cycle 5)

All of the optical reference information below pertains to the "Cycle 5" point design for the Observatory, which is the design described in the Science Definition Team report dated March 10, 2015 (Spergel et al, arXiv:1503.03757).

This file contains a compendium of basic information on the observatory and instruments, taken from the SDT report:
» Instr_RefInfo_20150701.pptx

This file gives the projection of instrument fields of view onto the sky (neglecting distortions). The numbering of the WFI detectors in this drawing corresponds to the Zemax 'Configurations' in the Zernike spreadsheet below.
» WFIRST_Field_Layout_5.0.6_150508.jpg

Point-spread functions for the WFIRST-AFTA Wide-Field Instrument (aka 'Wide Field Camera') can be computed at any wavelength and at any position in the field of view, given knowledge of the pupil function. The following files give Zernike decompositions of the wavefront error and pupil masks needed to perform this calculation. The first file contains the Zernike coefficients for the WFI, and also provides a fit to distortions in WFI imaging mode (WIM), a mapping of WIM detector positions onto the sky, WFI SCA positions in the focal plane, etc. Zernike coefficients are also provided for the grism Wide-Field Spectroscopy Mode (WSM) in first order, and for a single field position in 0th and 2nd order.
» AFTA_C5_WFC_Zernike_and_Field_Data_150717.xlsx

This README file provides additional information on the contents of the Zernike spreadsheet.
» README_AFTA_C5_WFC_Zernike_and_Field_Data.pdf

Similar wavefront error information for the IFU is provided in the next file, for two locations in the optical path: the image slicer and the detector surface. WFE information at the slit mirrors is not yet available.
» AFTA_C5_IFU_Zernike_Data_150630.xlsx

Sample PSF calculations for the IFU are provided in the next file:
» AFTA_C5_IFU_PSF_Samples_150630.xlsx
The ordering of the tabulated PSF data in this file is the same as for a displayed image: the first row in the table corresponds to the top of the image, and the first column corresponds to the left edge of the image, etc.

This file provides the dispersion solution for the IFU spectrograph:
» IFU_R-curves_data.xlsx

Information on the pupils is provided in the next set of files. The first file describes the orientation of the pupils, and includes other relevant information:
» WFIRST-AFTA_C5_WFI_Pupils_150630.pptx

The IFU pupil, applicable for both the image slicer and the detector surface:
» AFTA_IFU_C5_Pupil_Mask_Norm_2048px.tif

The WFC pupil, applicable for filters Z087, Y106, J129:
» AFTA_WFC_C5_Pupil_Shortwave_Norm_2048px.tif

The WFC pupil, applicable for filters H158, F184, W149, and the GRS grism:
» AFTA_WFC_C5_Pupil_Mask_Norm_2048px.tif

This spreadsheet gives the effective area for the wide-field imager through each filter and through the grism, and for both IFU channels. An updated version with extended wavelength coverage is forthcoming.
» WFIRST-WF-Cycle5_throughput_150518.xlsx

This file contains finer sampling of the distortion than is provided in the PSF_zernike_calculation_final04282015_rev.xlsx file.
» WFIRST_Distortion_Map_506.xlsx

This spreadsheet provides a calculator for each SCA giving the mapping in both directions between sky angle and wavelength to detector position.
» WFIRST_GRS_dispersion_fits_5-0-6.xlsx

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