Coronagraphy withtheWFIRSTAperture

N.JeremyKasdin

Whatmakesitchallenging?

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TheAFTAPupil TheAFTAPSF

Sayanythingabouthowthispupilmakesgettingsmallinnerworkinganglehard?

Coronagraphselectionbasedonmaturity,robustness,flexibility

PupilMasking(Kasdin, PrincetonUniversity)

PupilMapping(Guyon,Univ.Arizona)

ImagePlanePhaseMask(Serabyn,JPL)

ImagePlaneAmplitude&PhaseMask(Trauger,JPL)

VisibleNuller – PhaseOcculting(Clampin, NASAGSFC)VisibleNulller - DAVINCI(Shao, JPL)

HLCSPC

VVC VNC-POVNC - DAVINCI

PIAACMC

04/30/2014 WFIRST-AFTASDTInterimReport 3

ApproachtoRecommendation• Objective:Recommendaprimary andbackup coronagrapharchitecturetofocusdesignandtechnologydevelopmentleadingtopotentialnewmissionstartinF17

• RecommendationbyExEPOandASObasedoninputsfrom• SDT:Setsthesciencerequirements• ACWG:DeliverstechnicalFOMsandtechnologyplans

>Aimforthepositive:aconsensusproduct>SDTdeliversscienceFOMs

• TAC:AnalysisoftechnicalFOM,TRLreadinessplans,andrisks

• ExEPOandASOrecommendationtoAPDDirectorbasedon:

• TechnicalandProgrammatic• Musts(Requirements),Wants(Goals),andRisks• Distinguishdescriptionfromevaluation

• APDDirectorwillmakethedecision

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ACWG=representativesofExEPO,ASO,SDT,Community

Howdowedefineasuccessfuloutcome?

FOM=FigureofMerit

TAC:AlanBoss(CarnegieMellon)JoePitman(EXSCI)SteveRidgway(NOAO)LisaPoyneer (LLNL)BenOppenheimer(AMNH)

ACWGMembership• TheserepresentProgram,StudyOffice,SDT,andCommunity:

• AdditionalconsultantsparticipateatrequestofSteeringGroup

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Members:JeremyKasdin (PrincetonU)MarkMarley(NASAARC)MarcClampin (NASAGSFC)OlivierGuyon(UofA)GeneSerabyn (NASAJPL)StuartShaklan(NASAJPL)RemiSoummer(STScI)JohnTrauger (NASAJPL)MarshallPerrin(STScI)RickLyon(NASAGSFC)DaveContent(NASAGSFC)MarkMelton(NASAGSFC)CliffJackson(NASAGSFC)JohnRuffa (NASAGSFC)JenniferDooley(NASAJPL)MikeShao(NASAJPL)

Steering Group:GaryBlackwood(NASAJPL)KevinGrady(NASAGSFC)FengZhao(NASAJPL)PeterLawson(NASAJPL)ScottGaudi(OSU)NeilGehrels (NASAGSFC)DaveSpergel (PrincetonU)TomGreene(NASAARC)ChasBeichman(NExScI)JeffKruk(NASAGSFC)KarlStapelfeldt (NASAGSFC)WesTraub(NASAJPL)BruceMacIntosh(LLNL)

Charter

RecommendationCriteria:DefiningaSuccessfulOutcomeMUSTS(Requirements):Go/No_Go1. Science:Doestheproposedarchitecturemeetthebaseline sciencedrivers?2. Interfaces:Forthebaseline science,doesthearchitecturemeettelescopeandspacecraftrequirementsofthe

observatoryasspecifiedbytheAFTAproject(DCIL1)3. TechnologyReadinessLevel(TRL)Gates:Forbaseline science,isthereacredibleplantobeatTRL5atthestart

ofFY17andatTRL6atthestartofFY19withinavailableresources?4. Istheoptionreadyintimeforthisselectionprocess?

WANTS(Goals):Relativetoeachother,forthosethatpasstheMusts:1. Science:Relativestrengthofsciencebeyondthebaseline2. Technical:Relativetechnicalcriteria

- Seedetails3. Programmatic:RelativecostofplantomeetTRLGates

RISKSandOPPORTUNITIES- Seedetails

61DCL=DaveContentInterfaceList

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Hybrid Lyot Coronagraph

Baseline design for WFIRST/AFTA

From John Trauger, JPLTotalPSFcorethroughput =4.5%

Transmission=48%

No jitter0 mas

star

0.4 mas jitter1.0 mas star

0.8 mas jitter1.0 mas star

1.6 mas jitter1.0 mas star

HLC

SPC

PIAACMC

WFIRST Dark Holes with Pointing Jitter & Finite Star

WFIRST PIAACMC uses a single DM forsimplicity, so it has asingle-sided dark hole

r = 9 λ/D

Coronagraphsimulationsusevalidatedwave-opticscode

AFTAPupil Shaped Pupil Focal plane mask

r = 2.5 – 9 λ /Dc65° opening angle

27% mask transmission

Lyot stop

r = 0.3 – 0.9 rsp pup

TotalPSFcorethroughput =3.7%

Simulationsshowe.g.robustperformanceagainstjitter

1.6 mas RMS jitter0.8 mas RMS jitter0.4 mas RMS jitter No jitter

728– 872nmJitterlevelsshownhereareaftercoronagraphfasttip/tilt

SimulationsshowstablehighcontrastwithAFTAinthermalscenarios

• ProperEFCcorrectionfortelescopenominalwavefront(initialDMsetting)• Gen1SPCdesign,10%bandwidth, l=550nm,3.9~12.3l/DWA,56deg openingangle• RealisticAFTAsurfaceaberration(amplitude+phase),and• Piston/tip/tilt/focus correctioncomputedonlyonce initially• Thesystemconfigurationisheldconstantthroughouttheobservations

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Rawspeckle,S(t) ΔSpeckle (rel.tonominal):S(t)– S(0)

TypicalMeanContrast:~5.3e-9 TypicalMeanΔ Contrast:~4.4e-11

PIAA- CMC

DM1,DM2 Pupilmapping Apodizer mask Occultingmask Lyot stop Inversepupilmapping

MediumACADonbothDMs

PIAAmirrors Grayscale,filerwheels?

Phasetransmission,onfilterwheel

Transmission,binary,fixed?

InversePIAAmirrors

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FPA

ToLOWFSPIAAmirrors

InversePIAA

DM1/FSM

DM2

Finaldesigndeadlineextendedto11/4/2013

13December8-9,2015

CGIOperationalModes

Pupilmask

Lyotmask

Filterwheel

Fieldstopmask

toLOWFS

FSM

PBS

M4

M3

CORF1

R3OAP1

R3OAP2

COLF1

COLF2

FSOAP1

FSOAP2

Tertiary Collimator Assembly (TCA)

Coronagraph Instrument (CGI)

DM2

FocMR1OAP1

R1OAP2

R2OAP1

R2OAP2

DM1

FM

IFS/ImgSelector

FocalPlanemask

RadiationShieldMirror

FPA

Telescope

T1

T2

CORF2

IMG

HybridLyot ModeImagingin2simultaneouspolarizations,simulatedplanetsarecircledinred

14December8-9,2015

CGIOperationalModes

R3OAP1

TelescopeT2

Pupilmask

Lyotmask

Filterwheel

Fieldstopmask

FSM

M4

M3

CORF2

R3OAP1

R3OAP2

COLF1

COLF2

FSOAP1

FSOAP2

DM2

FocMR1OAP1

R1OAP2

R2OAP1

R2OAP2

DM1

FM

IFS/ImgSelectorFocalPlane

mask

T1

ShapedPupilSpectroscopyMode

FPA

IFS

IFS

CORF1

toLOWFS

TheIFSuses318%bandstoproduceanR=70spectrafrom600to970nm

lensletarray pinhole

maskdispersed

lenslet images

extracted datacube

SPCimagesin318%bands

Tertiary Collimator Assembly (TCA)

Coronagraph Instrument (CGI)

BackupSlides

Starlightsuppression-- TechnicalApproach

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Primaryapproach

Back-upapproach

Downselect1/6/2014

TRL-5@startofPhaseA(10/2016) TRL-6@PDR(10/2018)

VisibleNuller Coronagraph:Phase-Occulting(Lyon,GSFC)

VisibleNuller Coronagraph:DaVinci (Shao,JPL)

Sixdifferentconcepts

HybridLyot

DM1,DM2 Pupilmapping Apodizer mask Occultingmask Lyot stop Inversepupilmapping

MildACADonboth DMs

Complextransmission,onfilterwheel

Transmission,grey,fixed

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FPA

DM1/FSM

DM2

ToLOWFS

ShapedPupil

DM1,DM2 Pupilmapping Apodizer mask Focalplanemask Lyot stop Inversepupilmapping

MildACADonbothDMs

Binaryreflectiononfilterwheels

Binarytransmission,onfilterwheel

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FPA

ToLOWFS

DM1/FSM

DM2

VectorVortex

DM1,DM2 Pupilmapping Apodizer mask Focalplanemask Lyot stop Inversepupilmapping

Strong ACADonbothDMs

Binarytransmission, onfilterwheel

Vortextransmission,onfilterwheel

Transmission,binary,fixed

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FPA

ToLOWFS?

DM1/FSM

DM2

PIAA- CMC

DM1,DM2 Pupilmapping Apodizer mask Occultingmask Lyot stop Inversepupilmapping

MediumACADonbothDMs

PIAAmirrors Grayscale,filerwheels?

Phasetransmission,onfilterwheel

Transmission,binary,fixed?

InversePIAAmirrors

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FPA

ToLOWFSPIAAmirrors

InversePIAA

DM1/FSM

DM2

Finaldesigndeadlineextendedto11/4/2013

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FromAFTATelescope

APSClock90°

AFTAExitPupilVNCEntrancePupil

BS

ToScienceToWFC

GregorianRelayw/POOptics

BS9.5mmfused silica

AFTA:Phase-OccultedVNCNullingSchematic

Interferometer WFC

1stagenullinginterferometer TwoDMsforbothphaseandamp

Fullaperture(radialshear) Lyot stop?

Achromaticphaseshifters*

DelaylinetoadjustOPD

VNC-DaVinci

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Interferometer WFC

2stagenullinginterferometers OneDM(4quadrants)forbothphaseandamplitudecontrol

Dilutedaperture(4X) Lyot stopmask(binary,transmission,fixed)

Achromaticphaseshifters Fiberbundlespatial filters

Delay linetoadjustOPD

FPA

p

p 00

p

p 00

DM