Spacecraft and Instrument Parameters

The following parameters refer to the telescope design as specified for Phase C. Additional Phase C reference files are available at GSFC. These include the field-of-view layout, detector properties, distortions, Zernike decompositions of the PSFs, pupil masks, transmission/effective area per filter, and more. Additional Coronagraph Instrument parameters and data are also available.

These spacecraft/instrument parameters, which are to be used in simulations and in designing science projects, are tied to a regular project design schedule (see the link to parameters in earlier mission phases below). To ensure consistency within the community, these parameters are released here only after approval by the Roman Space Telescope Project Scientist.


Parameter Categories

List of Previous Spacecraft and Instrument Parameters.


Parameters as CSV Table

To get all parameters as a plain text CSV table, copy and paste desired rows from here (If using Chrome, please use right click and select "Open Link in New Tab"), or right-click and select "Save/Download Link As" and name the file as desired.


Parameter Tables

(Mouse over table cells to see full contents. Click column headers to sort.)

Mission and Spacecraft Parameters

NameValueUnitDescription
Mission_Duration_Requirement5yearsMission duration requirement
Mission_Duration_Goal10yearsMission duration goal
Mission_Launch_SiteCape Canaveral Air Force Station, FloridaLaunch site
Spacecraft_Operating_Temperature298KOperating temperature of the spacecraft
Spacecraft_Orbit_TypeSun-Earth L2Type of spacecraft orbit
Spacecraft_Downlink_Rate275MbpsSpacecraft downlink rate
Spacecraft_Downlink_Volume11Tbits/daySpacecraft downlink volume
Spacecraft_Slew_Angle_Gap_Fill0.025degreesGap fill slew angle
Spacecraft_Slew_Time_Gap_Fill21.4secondsGap fill slew time
Spacecraft_Slew_Angle_Short_FoV0.4degreesShorter side of field-of-view slew angle (six reaction wheel operation)
Spacecraft_Slew_Time_Short_FoV49.3secondsShorter side of field-of-view slew time (including the settle time; six reaction wheel operation)
Spacecraft_Slew_Angle_Long_FoV0.8degreesLong side of field-of-view slew angle (six reaction wheel operation)
Spacecraft_Slew_Time_Long_FoV67.4secondsLong side of field-of-view slew time (including the settle time; six reaction wheel operation)
Spacecraft_Slew_Angle_Microlensing_Maximum2.06degreesMaximum microlensing slew angle (six reaction wheel operation)
Spacecraft_Slew_Time_Microlensing_Maximum99secondsMaximum microlensing slew time (including the settle time; six reaction wheel operation)
Spacecraft_Slew_Time_Two_Degrees99secondsTwo degree slew time (including the settle time; six reaction wheel operation)
Spacecraft_Slew_Time_Five_Degrees162secondsFive degree slew time (including the settle time; six reaction wheel operation)
Spacecraft_Slew_Time_Ten_Degrees267secondsTen degree slew time (including the settle time; six reaction wheel operation)
Spacecraft_Slew_Time_Thirty_Degrees667secondsThirty degree slew time (including the settle time; six reaction wheel operation)
Spacecraft_Slew_Time_Ninety_Degrees1865secondsThirty degree slew time (including the settle time; six reaction wheel operation)
Spacecraft_Slew_Settling_Time_Small10+slew angle (degrees)secondsSpacecraft settling time after a slew of less than ten degrees
Spacecraft_Slew_Settling_Time_Large20secondsSpacecraft settling time after a slew of more than ten degrees


Telescope Parameters

NameValueUnitDescription
Telescope_Jitter12milliarcsecTelescope jitter for high frequencies (vibration modes in the optics) per axis (rms)
Telescope_Drift8milliarcsecTelescope drift at frequencies within the Attitude Control System's bandwidth per axis (rms)
Telescope_Primary_Diameter2.36mDiameter of the telescope primary mirror
Telescope_Primary_Mirror_Temperature265KTelescope primary mirror temperature
Telescope_Central_Obscuration30.3%Linear obscuration of the telescope entrance pupil (diameter ratio)
Telescope_Allowed_Pitch_Range54-126degreesAllowed telecope pitch range towards (0 degrees) the Sun and away (180 degrees) from the Sun
Telescope_Allowed_Yaw_Range0-360degreesAllowed telecope yaw range about the Sun line
Telescope_Allowed_Roll_Range-15-+15degreesAllowed telecope roll about the line of sight (off maximum power roll angle)


WFI Imager Parameters

NameValueUnitDescription
WFI_Correlated_Noise5e-WFI detector correlated noise floor
WFI_Count_Rate_Zody_Minimum_F0620.27Count rate per pixel in the F062 filter at minimum zodiacal light
WFI_Count_Rate_Zody_Minimum_F0870.27Count rate per pixel in the F087 filter at minimum zodiacal light
WFI_Count_Rate_Zody_Minimum_F1060.29Count rate per pixel in the F106 filter at minimum zodiacal light
WFI_Count_Rate_Zody_Minimum_F1290.28Count rate per pixel in the F129 filter at minimum zodiacal light
WFI_Count_Rate_Zody_Minimum_F1580.26Count rate per pixel in the F158 filter at minimum zodiacal light
WFI_Count_Rate_Zody_Minimum_F1840.15Count rate per pixel in the F184 filter at minimum zodiacal light
WFI_Count_Rate_Zody_Minimum_F1460.85Count rate per pixel in the F146 filter at minimum zodiacal light
WFI_Count_Rate_Zody_Minimum_F2130.13Count rate per pixel in the F213 filter at minimum zodiacal light
WFI_Count_Rate_Zody_Minimum_Prism0.95Count rate per pixel in the Prism at minimum zodiacal light
WFI_Count_Rate_Zody_Minimum_Grism0.65Count rate per pixel in the Grism at minimum zodiacal light
WFI_Dark_Current< 0.1e-/s/pixelWFI detector dark current per pixel (requirement)
WFI_Detector_Guide_Star_Update_Rate~5.8HzGuide star update rate
WFI_Detector_TypeH4RG-10Detector type for WFI
WFI_Detector_Quantum_Efficiency_Long>80%WFI detector quantum efficiency (requirement; average over wavelengths between 0.8 and 2.1 microns
WFI_Detector_Quantum_Efficiency_Short>60%WFI detector quantum efficiency (requirement; average over wavelengths between 0.6 and 0.8 microns
WFI_Detector_Readout_Time3.04secSensor Chip Assembly full frame readout time
WFI_Detector_Pixel_Operability>95%WFI detector pixel operability (requirement)
WFI_Detector_Total_Crosstalk<12%WFI detector total crosstalk (requirement)
WFI_Detector_Total_Noise_180s5-6electronsWFI detector total noise (rms uncertainty in slope fit for an exposure time of 180 sec)
WFI_Detector_Inter_Pixel_Capacitance0.9119WFI detector inter-pixel capacitance (fraction of a pixel-centered total charge of 1 actually deposited in the central pixel)
WFI_Detector_Full_Frame_Readout_Time2.74secondsWFI detector full frame readout time
WFI_Field_Of_View_Effective0.281deg2WFI total effective field of view (ignoring gaps between detectors)
WFI_Field_Of_View_Total0.32deg2WFI total field of view (including gaps between detectors)
WFI_Focal_Ratio7.9WFI instrument and telescope's combined focal ratio
WFI_Number_Of_Active_Columns4088pixelNumber of active detector columns (also known as the number of pixels in the x-direction) in (the image section of) a detector
WFI_Number_Of_Active_Rows4088pixelNumber of active detector rows (also known as the number of pixels in the y-direction) in (the image section of) a detector
WFI_Jitter_Wavefront_Error< 0.707nmTelescope intermediate focus wavefront error jitter (requirement)
WFI_Image_Stability1.0nmRMS wave front error (WFE) variation in 180 sec
WFI_Pixel_Scale0.11arcsecWFI detector pixel scale in arcseconds/pixel
WFI_Pixel_Size1010-6 mWFI wide-field channel pixel size in each dimension
WFI_PSF_Ellipticity< 0.00047WFI point spread function ellipticity per 184 seconds at WFI focus
WFI_Readout_Noise< 20e-WFI detector pixel readout noise rms for correlated double sampling (two successive detector readouts)
WFI_Temperature< 100KWFI detector operating temperature
WFI_Number18Total number of scientific detectors in WFI


WFI Filter Parameters

NameValueUnitDescription
WFI_Filter_F062_Center0.62010-6 mWFI filter F062 central wavelength
WFI_Filter_F087_Center0.86910-6 mWFI filter F087 central wavelength
WFI_Filter_F106_Center1.06010-6 mWFI filter F106 central wavelength
WFI_Filter_F129_Center1.29310-6 mWFI filter F129 central wavelength
WFI_Filter_F158_Center1.57710-6 mWFI filter F158 central wavelength
WFI_Filter_F184_Center1.84210-6 mWFI filter F184 central wavelength
WFI_Filter_F213_Center2.12510-6 mWFI filter F213 central wavelength
WFI_Filter_F146_Center1.46410-6 mWFI filter F146 central wavelength
WFI_Filter_F062_Resolving_Power2.2WFI filter F062 resolving power
WFI_Filter_F087_Resolving_Power4WFI filter F087 resolving power
WFI_Filter_F106_Resolving_Power4WFI filter F106 resolving power
WFI_Filter_F129_Resolving_Power4WFI filter F129 resolving power
WFI_Filter_F158_Resolving_Power4WFI filter F158 resolving power
WFI_Filter_F184_Resolving_Power5.81WFI filter F184 resolving power
WFI_Filter_F213_Resolving_Power6.07WFI filter F213 resolving power
WFI_Filter_F146_Resolving_Power1.42WFI filter F146 resolving power
WFI_Filter_F062_Wavelength_Range0.480-0.76010-6 mWFI filter F062 wavelength range
WFI_Filter_F087_Wavelength_Range0.760-0.97710-6 mWFI filter F087 wavelength range
WFI_Filter_F106_Wavelength_Range0.927-1.19210-6 mWFI filter F106 wavelength range
WFI_Filter_F129_Wavelength_Range1.131-1.45410-6 mWFI filter F129 wavelength range
WFI_Filter_F158_Wavelength_Range1.380-1.77410-6 mWFI filter F158 wavelength range
WFI_Filter_F184_Wavelength_Range1.683-2.00010-6 mWFI filter F184 wavelength range
WFI_Filter_F213_Wavelength_Range1.950-2.30010-6 mWFI filter F213 wavelength range
WFI_Filter_F146_Wavelength_Range0.927-2.00010-6 mWFI filter F146 wavelength range
WFI_Filter_Wavelength_BlankWFI blank for dark current, flat field and other calibrations with internal light source


WFI Grism Parameters

NameValueUnitDescription
WFI_Grism_Dispersion1.04-1.14nm/pixelWFI Grism dispersion, dependent mostly on the FPA Y value in degrees (Y axis is positive towards payload origin and FPA Y axis origin is between detectors 1 and 10) as -0.1945Y + 1.0764.
WFI_Grism_Wavelength_Range_G1501.00-1.9310-6 mWFI Grism wavelength range
WFI_Grism_Spectral_Resolving_Power_G150461lambdaWFI Grism resolving power (lambda in microns; two pixels)


WFI Prism Parameters

NameValueUnitDescription
WFI_Prism_Wavelength_Range_P1270.75-1.8010-6 mWFI prism wavelength range
WFI_Prism_Spectral_Resolving_Power_P12780-180WFI Prism resolving power (delta lambda = two pixels)


WFI Sensitivity Parameters

NameValueUnitDescription
WFI_Sensitivity_Grism_Point_Source_Short21.0AB magWFI Grism limiting point source sensitivity (10-sigma per pixel in continuum) at 1.2 microns in 1 hour of exposure time, zodiacal light set at twice the minimum value
WFI_Sensitivity_Grism_Point_Source_Long20.7AB magWFI Grism limiting point source sensitivity (10-sigma per pixel in continuum) at 1.5 microns in 1 hour of exposure time, zodiacal light set at twice the minimum value
WFI_Sensitivity_Prism_Point_Source_Short22.2AB magWFI prism limiting point source sensitivity (10-sigma per pixel in continuum) at 0.8 microns in 1 hour of exposure time, zodiacal light set at twice the minimum value
WFI_Sensitivity_Prism_Point_Source_Medium23.0AB magWFI prism limiting point source sensitivity (10-sigma per pixel in continuum) at 1.2 microns in 1 hour of exposure time, zodiacal light set at twice the minimum value
WFI_Sensitivity_Prism_Point_Source_Long23.0AB magWFI prism limiting point source sensitivity (10-sigma per pixel in continuum) at 1.5 microns in 1 hour of exposure time, zodiacal light set at twice the minimum value
WFI_Sensitivity_F062_Point_Source28.6AB magWFI filter F062 limiting point source sensitivity (5-sigma) in 1 hour of exposure time, zodiacal light set at twice the minimum value
WFI_Sensitivity_F087_Point_Source28.2AB magWFI filter F087 limiting point source sensitivity (5-sigma) in 1 hour of exposure time, zodiacal light set at twice the minimum value
WFI_Sensitivity_F106_Point_Source28.1AB magWFI filter F106 limiting point source sensitivity (5-sigma) in 1 hour of exposure time, zodiacal light set at twice the minimum value
WFI_Sensitivity_F129_Point_Source28.0AB magWFI filter F129 limiting point source sensitivity (5-sigma) in 1 hour of exposure time, zodiacal light set at twice the minimum value
WFI_Sensitivity_F158_Point_Source28.0AB magWFI filter F158 limiting point source sensitivity (5-sigma) in 1 hour of exposure time, zodiacal light set at twice the minimum value
WFI_Sensitivity_F184_Point_Source27.5AB magWFI filter F184 limiting point source sensitivity (5-sigma) in 1 hour of exposure time, zodiacal light set at twice the minimum value
WFI_Sensitivity_F213_Point_Source26.2AB magWFI filter F213 limiting point source sensitivity (5-sigma) in 1 hour of exposure time, zodiacal light set at twice the minimum value
WFI_Sensitivity_F146_Point_Source28.3AB magWFI filter F146 limiting point source sensitivity (5-sigma) in 1 hour of exposure time, zodiacal light set at twice the minimum value
WFI_Sensitivity_110_Point_Source_Emission_Line5.710-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a point source at 1.1 microns, zodiacal light set at twice the minimum value
WFI_Sensitivity_110_Extended_Source_Emission_Line11.010-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a source with half light radius = 0.2 arcsec at 1.1 microns, zodiacal light set at twice the minimum value
WFI_Sensitivity_120_Point_Source_Emission_Line4.310-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a point source at 1.2 microns, zodiacal light set at twice the minimum value
WFI_Sensitivity_120_Extended_Source_Emission_Line8.210-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a source with half light radius = 0.2 arcsec at 1.2 microns, zodiacal light set at twice the minimum value
WFI_Sensitivity_130_Point_Source_Emission_Line3.810-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a point source at 1.3 microns, zodiacal light set at twice the minimum value
WFI_Sensitivity_130_Extended_Source_Emission_Line7.110-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a source with half light radius = 0.2 arcsec at 1.3 microns, zodiacal light set at twice the minimum value
WFI_Sensitivity_140_Point_Source_Emission_Line3.610-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a point source at 1.4 microns, zodiacal light set at twice the minimum value
WFI_Sensitivity_140_Extended_Source_Emission_Line6.710-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a source with half light radius = 0.2 arcsec at 1.4 microns, zodiacal light set at twice the minimum value
WFI_Sensitivity_150_Point_Source_Emission_Line3.610-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a point source at 1.5 microns, zodiacal light set at twice the minimum value
WFI_Sensitivity_150_Extended_Source_Emission_Line7.010-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a source with half light radius = 0.2 arcsec at 1.5 microns, zodiacal light set at twice the minimum value
WFI_Sensitivity_160_Point_Source_Emission_Line3.910-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a point source at 1.6 microns, zodiacal light set at twice the minimum value
WFI_Sensitivity_160_Extended_Source_Emission_Line7.210-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a source with half light radius = 0.2 arcsec at 1.6 microns, zodiacal light set at twice the minimum value
WFI_Sensitivity_170_Point_Source_Emission_Line4.210-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a point source at 1.7 microns, zodiacal light set at twice the minimum value
WFI_Sensitivity_170_Extended_Source_Emission_Line7.210-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a source with half light radius = 0.2 arcsec at 1.7 microns, zodiacal light set at twice the minimum value
WFI_Sensitivity_180_Point_Source_Emission_Line5.010-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a point source at 1.8 microns, zodiacal light set at twice the minimum value
WFI_Sensitivity_180_Extended_Source_Emission_Line8.410-17 ergs cm-2sec-1WFI emission line detected at 6.5-sigma in one hour for a source with half light radius = 0.2 arcsec at 1.8 microns, zodiacal light set at twice the minimum value


Fully Commissioned Coronagraph Instrument Observing Modes

NameValueUnitDescription
CGI_Mode_Imaging_NNarrow FoV imaging. Currently implemented as HLC coronagraph + Band 1 filter + imaging camera
CGI_Mode_Imaging_WWide FoV imaging. Currently implemented as SPC_A coronagraph + Band 4 filter + imaging camera
CGI_Mode_SpectroscopySingle Slit, Prism-based Spectroscopy. Currently implemented as SPC_B coronagraph + Band 3 filter + Spectroscopy


Coronagraph Instrument Coronagraph Parameters

NameValueUnitDescription
CGI_Coronagraph_HLCHLC = Hybrid Lyot Coronagraph
CGI_Coronagraph_SPC_ASPC_A = Shaped Pupil Coronagraph for large outer working angle in an annular field of view
CGI_Coronagraph_SPC_BSPC_B = Shaped Pupil Coronagraph for small inner working angle in a `bowtie' shaped field of view
CGI_Coronagraph_Inner_Working_Angle_HLC3lambda/DInner radius of region of highest contrast
CGI_Coronagraph_Inner_Working_Angle_SPC_A5.9lambda/DInner radius of region of highest contrast
CGI_Coronagraph_Inner_Working_Angle_SPC_B3lambda/DInner radius of region of highest contrast
CGI_Coronagraph_Outer_Working_Angle_HLC9.7lambda/DOuter radius of region of highest contrast
CGI_Coronagraph_Outer_Working_Angle_SPC_A20.1lambda/DOuter radius of region of highest contrast
CGI_Coronagraph_Outer_Working_Angle_SPC_B9.1lambda/DOuter radius of region of highest contrast
CGI_Coronagraph_Annular_Size_HLC360degreesSuppression region annular extent
CGI_Coronagraph_Annular_Size_SPC_A360degreesSuppression region annular extent
CGI_Coronagraph_Annular_Size_SPC_B130degreesSuppression region annular extent


Coronagraph Instrument Primary Observing Bandpass Parameters

NameValueUnitDescription
CGI_Bandpass_Center1573.8nmCentral wavelength for bandpass 1
CGI_Bandpass_FWHM156.5nmNominal FWHM (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 1
CGI_Bandpass_Center2659.4nmCentral wavelength for bandpass 2
CGI_Bandpass_FWHM2110.9nmNominal FWHM (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 2
CGI_Bandpass_Center3729.3nmCentral wavelength for bandpass 3
CGI_Bandpass_FWHM3122.3nmNominal FWHM (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 3
CGI_Bandpass_Center4825.5nmCentral wavelength for bandpass 4
CGI_Bandpass_FWHM496.8nmNominal FWHM (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 4
CGI_Bandpass_ND_2pt25_FPAM102.25Attenuation factor of Neutral Density filter used for target acquisition (ND 2.25) mounted in FPAM
CGI_Bandpass_ND_4pt75_FPAM104.75Attenuation factor of Neutral Density filter used for target acquisition (ND 4.75) mounted in FPAM
CGI_Bandpass_ND_4pt75_FSAM104.75Attenuation factor of Neutral Density filter used for target acquisition (ND 4.75) mounted in FSAM


Coronagraph Instrument Engineering Bandpass Parameters

NameValueUnitDescription
CGI_Bandpass_Engineering_Center1a554.8nmCentral wavelength for engineering filter 1a (WFSC), Wavefront Sensing and Control (WFSC)
CGI_Bandpass_Engineering_FWHM1a18nmNominal FWHM [nm] (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 1a
CGI_Bandpass_Engineering_Center1b574.5nmCentral wavelength for engineering filter 1b (WFSC)
CGI_Bandpass_Engineering_FWHM1b18nmNominal FWHM [nm] (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 1b
CGI_Bandpass_Engineering_Center1c594.7nmCentral wavelength for engineering filter 1c (WFSC)
CGI_Bandpass_Engineering_FWHM1c19nmNominal FWHM [nm] (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 1c
CGI_Bandpass_Engineering_Center2a614.2nmCentral wavelength for engineering filter 2a
CGI_Bandpass_Engineering_FWHM2a21.6nmNominal FWHM [nm] (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 2a
CGI_Bandpass_Engineering_Center2b639.4nmCentral wavelength for engineering filter 2b
CGI_Bandpass_Engineering_FWHM2b15.1nmNominal FWHM [nm] (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 2b
CGI_Bandpass_Engineering_Center2c656nmCentral wavelength for engineering filter 2c
CGI_Bandpass_Engineering_FWHM2c6.2nmNominal FWHM [nm] (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 2c
CGI_Bandpass_Engineering_Center3a680.6nmCentral wavelength engineering filter 3a (Spectroscopy calibration)
CGI_Bandpass_Engineering_FWHM3a24.9nmNominal FWHM [nm] (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 3a
CGI_Bandpass_Engineering_Center3b702.3nmCentral wavelength engineering filter 3b (Spectroscopy calibration)
CGI_Bandpass_Engineering_FWHM3b23nmNominal FWHM [nm] (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 3b
CGI_Bandpass_Engineering_Center3c725.9nmCentral wavelength engineering filter 3c (Spectroscopy calibration)
CGI_Bandpass_Engineering_FWHM3c20nmNominal FWHM [nm] (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 3c
CGI_Bandpass_Engineering_Center3g752.5nmCentral wavelength engineering filter 3g (Spectroscopy calibration)
CGI_Bandpass_Engineering_FWHM3g24.1nmNominal FWHM [nm] (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 3g
CGI_Bandpass_Engineering_Center3d753.3nmCentral wavelength engineering filter 3d (Spectroscopy calibration)
CGI_Bandpass_Engineering_FWHM3d7.2nmNominal FWHM [nm] (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 3d
CGI_Bandpass_Engineering_Center3e777.1nmCentral wavelength engineering filter 3e (Spectroscopy calibration)
CGI_Bandpass_Engineering_FWHM3e27.1nmNominal FWHM [nm] (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 3e
CGI_Bandpass_Engineering_Center4a791.7nmCentral wavelength for engineering filter 4a (WFSC)
CGI_Bandpass_Engineering_FWHM4a29.8nmNominal FWHM [nm] (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 4a
CGI_Bandpass_Engineering_Center4b823.9nmCentral wavelength for engineering filter 4b (WFSC)
CGI_Bandpass_Engineering_FWHM4b28nmNominal FWHM [nm] (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 4b
CGI_Bandpass_Engineering_Center4c856.5nmCentral wavelength for engineering filter 4c (WFSC)
CGI_Bandpass_Engineering_FWHM4c30.2nmNominal FWHM [nm] (from 50% peak transmission cut-on to 50% peak transmission cut-off wavelength) for bandpass 4c


Coronagraph Instrument Detector Parameters

NameValueUnitDescription
CGI_Detector_ModelT-e2v CCD 311Detector make and model
CGI_Detector_Pixel_Number_X1056The EXCAM image array size in detector pixels in x-dimension for imaging and spectroscopy
CGI_Detector_Pixel_Number_Y1037The EXCAM image array size in detector pixels in y-dimension for imaging and spectroscopy
CGI_Detector_Pixel_Size1310-6 mPixel size of CGI detector pixels in each dimension, both imaging and spectroscopy
CGI_Detector_Pixel_Scale0.0218arcsec/pixelCoronagraph imaging pixel scale, Nyquist sampled (lambda/2D) at 500 nm
CGI_Detector_Readnoise120e-Current best estimate read noise when using the electron multiplying (EM) gain in photon counting mode
CGI_Detector_Saturation80000e-CGI detector image area full well, current best estimate
CGI_Detector_Dark_Current_BOL_CBE0.05e-/pixel/hrMean CGI dark current for T = 168 K (beginning of life current best estimate)
CGI_Detector_Dark_Current_EOL_CBE0.10e-/pixel/hrMean CGI dark current for T = 168 K (end of life current best estimate)
CGI_Detector_Clock_Induced_Charge_BOL0.016e-/pixel/frameCGI clock-induced charge (beginning of life), 10 MHz horizontal frequency; 1 MHz vertical frequency; serial clock swing < 10 V
CGI_Detector_Clock_Induced_Charge_EOL0.030e-/pixel/frameCGI clock-induced charge (end of life), 10 MHz horizontal frequency; 1 MHz vertical frequency; serial clock swing < 10 V
CGI_Detector_Quantum_Efficiency_44262.8%The EXCAM quantum efficiency at 442 nm
CGI_Detector_Quantum_Efficiency_45069.5%The EXCAM quantum efficiency at 450 nm
CGI_Detector_Quantum_Efficiency_48877.9%The EXCAM quantum efficiency at 488 nm
CGI_Detector_Quantum_Efficiency_58083.7%The EXCAM quantum efficiency at 580 nm
CGI_Detector_Quantum_Efficiency_68573.7%The EXCAM quantum efficiency at 685 nm
CGI_Detector_Quantum_Efficiency_73064.0%The EXCAM quantum efficiency at 730 nm
CGI_Detector_Quantum_Efficiency_83041.2%The EXCAM quantum efficiency at 830 nm
CGI_Detector_Quantum_Efficiency_88526.4%The EXCAM quantum efficiency at 885 nm
CGI_Detector_Quantum_Efficiency_95011.6%The EXCAM quantum efficiency at 930 nm
CGI_Detector_Quantum_Efficiency_9806.8%The EXCAM quantum efficiency at 980 nm


Coronagraph Instrument Imaging Parameters

NameValueUnitDescription
CGI_Imaging_FoV7.2arcsecUnvignetted coronagraph imaging field-of-view diameter without coronagraph masks


Coronagraph Instrument Spectroscopy Parameters

NameValueUnitDescription
CGI_Spectroscopy_FoV4arcsecUnvignetted FoV diameter without masks in each spectral channel
CGI_Spectroscopy_Footprint_Of_Dispersed_Point_Source_Band242x4pixelsSpectroscopic footprint of dispersed point source in pixels; the smaller axis (cross-dispersion) includes only the main lobe of the PSF
CGI_Spectroscopy_Footprint_Of_Dispersed_Point_Source_Band347x4pixelsSpectroscopic footprint of dispersed point source in pixels; the smaller axis (cross-dispersion) includes only the main lobe of the PSF
CGI_Spectroscopy_Band2_Short_Slit_Width0.115arcsecBand 2 spectroscopy slit width for 2lambda/D wide, 6lambda/D long "short" slit
CGI_Spectroscopy_Band2_Short_Slit_Height0.345arcsecBand 2 spectroscopy slit height for 2lambda/D wide, 6lambda/D long "short" slit
CGI_Spectroscopy_Band2_Tall_Slit_Width0.115arcsecBand 2 spectroscopy slit width for 2lambda/D wide, 10lambda/D long "tall" slit
CGI_Spectroscopy_Band2_Tall_Slit_Height0.575arcsecBand 2 spectroscopy slit height for 2lambda/D wide, 10lambda/D long "tall" slit
CGI_Spectroscopy_Band3_Short_Slit_Width0.127arcsecBand 3 spectroscopy slit width for 2lambda/D wide, 6lambda/D long "short" slit
CGI_Spectroscopy_Band3_Short_Slit_Height0.381arcsecBand 3 spectroscopy slit height for 2lambda/D wide, 6lambda/D long "short" slit
CGI_Spectroscopy_Band3_Tall_Slit_Width0.127arcsecBand 3 spectroscopy slit width for 2lambda/D wide, 10lambda/D long "tall" slit
CGI_Spectroscopy_Band3_Tall_Slit_Height0.635arcsecBand 3 spectroscopy slit height for 2lambda/D wide, 10lambda/D long "tall" slit
CGI_Spectroscopy_Bands23_Mean_Short_Slit_Width0.243arcsecBands 2-3 mean (695 nm) spectroscopy slit width for 4lambda/D wide, 6lambda/D long "short" slit
CGI_Spectroscopy_Bands23_Mean_Short_Slit_Height0.3645arcsecBands 2-3 mean (695 nm) spectroscopy slit height for 4lambda/D wide, 6lambda/D long "short" slit
CGI_Spectroscopy_Bands23_Mean_Tall_Slit_Width0.243arcsecBands 2-3 mean (695 nm) spectroscopy slit width for 4lambda/D wide, 10lambda/D long "tall" slit
CGI_Spectroscopy_Bands23_Mean_Tall_Slit_Height0.6075arcsecBands 2-3 mean (695 nm) spectroscopy slit height for 4lambda/D wide, 10lambda/D long "tall" slit
CGI_Spectroscopy_Spectral_Resolution50lambda/(delta lambda)Spectral resolution at the centers of Band 2 (660 nm) and Band 3 (730 nm)

Additional Coronagraph Instrument Parameters and Data


Coronagraph Instrument Polarimetry Parameters

NameValueUnitDescription
CGI_Polarimetry_FoV3.8arcsecUnvignetted FoV diameter without masks in each polarization angle
CGI_Polarimetry_Wollaston_Prism10 and 90degreesPolarization angles for the first Wollaston prism
CGI_Polarimetry_Wollaston_Prism245 and 135degreesPolarization angles for the second Wollaston prism


Coronagraph Instrument Predicted Performance Parameters

Python code to calculate and plot the Roman Coronagraph’s flux ratio vs separation (working angle)
NameValueUnitDescription
CGI_Predicted_Performance_Imaging_N_Contrast_Pred3.07x10-9Predicted planet-to-star flux ratio for an SNR=5 imaging detection in band 1 with HLC, 100hr integration, after post-processing at a separation of 4.39lambda/D (=216.94 mas). This prediction is based on modeling and error budgeting of Nancy Grace Roman Space Telescope observatory and CGI, including: observatory and instrument stability during CGI con-ops, coronagraph starlight suppression performance, detector properties, and post-processing gains. Coronagraph and detector models have been validated against experimental results. Does not include model uncertainty factors on observatory or coronagraph performance (i.e., MUF=1)
CGI_Predicted_Performance_Imaging_W_Contrast_Pred2.39x10-9Predicted planet-to-star flux ratio for an SNR=5 imaging detection in band 4 with SPC, 100hr integration, after post-processing at a separation of 6lambda/D (=432.63 mas). This prediction is based on modeling and error budgeting of Nancy Grace Roman Space Telescope observatory and CGI, including: observatory and instrument stability during CGI con-ops, coronagraph starlight suppression performance, detector properties, and post-processing gains. Coronagraph and detector models have been validated against experimental results. Does not include model uncertainty factors on observatory or coronagraph performance (i.e., MUF=1)
CGI_Predicted_Performance_Spectroscopy_Contrast_Pred5.00x10-9Predicted planet-to-star flux ratio for an SNR=5 spectrum in band 3 with SPC_B (bowtie), 100hr integration, after post-processing at a separation of 4.39lambda/D (=280.09 mas). This prediction is based on modeling and error budgeting of Nancy Grace Roman Space Telescope observatory and CGI, including: observatory and instrument stability during CGI con-ops, coronagraph starlight suppression performance, detector properties, and post-processing gains. Coronagraph and detector models have been validated against experimental results. Does not include model uncertainty factors on observatory or coronagraph performance (i.e., MUF=1)
CGI_Predicted_Performance_45offaxis_scattered_light3.4x10-9Scattered light flux ratio per resolution element from a source 45 arcsec off axis. Applicable to all coronagraph modes
CGI_Predicted_Performance_100offaxis_scattered_light3.5x10-10Scattered light flux ratio per resolution element from a source 100 arcsec off axis. Applicable to all coronagraph modes


Coronagraph Instrument Observing Requirements

NameValueUnitDescription
CGI_Host_Star_Vmag_Requirement=< 5AB magCGI host star requirement is V_AB mag<=5; CGI could potentially observe dimmer targets (V = 6-7 AB mag), but this is TBD