Design Review

Far Ultraviolet SpectroPolarimeter(FUSP)

36.173UG

Target: Beta and Zeta Tau

K. NordsieckUniversity of Wisconsin

Nov 17, 1999

• Science Overview• Experiment Design Overview• Heritage• Flight Events• Interfaces• Mission Success Criteria• Schedule

FUSP Scientific Goals: the first Astronomical Polarimetry below 1300 D

• Circumstellar envelope geometry in hot stars (supergiants, Oe/Be, WR,interacting binaries)

• Test new magnetic field diagnostic - “Hanle Effect”• Look for new continuum polarization effect - H Rayleigh scattering• Nature of very small interstellar dust grains.

Technique

• Linear polarization across spectral lines formed in stellar winds. - Astro/WUPPE showed unexpected strong line blanketing effects in

Be star polarization. Attributed to FeII absorption in scatteringdisk.

- Far UV has “resonance lines” which should themselves be polarized, depending on geometry and magnetic field

• Continuum linear polarization near Ly "

Requirements

• Resolution: high enough for line profiles => minimize jitter• Polarimetry: 0.01% precision• Highest possible throughput and exposure time for required S/N• Wavelengths: As low as possible

< 1500Å covers main resonance lines

SpecificationsResolution: 88/)8)8 = 1800 ()8)8 = 0.7DD)Aperture: 20 inch (F/2.5)Focal Scale 1 pixel = 24:: = 4 arcsec = 0.44 DDWavelengths: 1050 -1500DD Polarimetry: Modulated Single-Beam

Some FUSP Targets

Flight Program Target V m1330 Exp(s) )8(D) %Err

1(36.173)

UnpolBe

$ Tau. Tau

23

-0.5-0.3

50300

101

0.030.05

2 HanleHanle

. Ori> Per

24

-2.51.0

200150

11

0.020.1

3 IntBinISM

$ LyrF Sco

3.53

2. -0.5

200150

110

0.160.02

Targets for first Flight (36.173UG): $ Tau/ . Tau

FUSP Launch Window for WSMR

Target RA= 5 37 38 Dec= 21 8 34 (Zeta Tau) Zenith Distance s: Sun < 120 t: Target > 65

Local Time:yyyymmdd 18 19 20 21 22 23 0 1 2 3 4 5 6 | | | | | | | | | | | | |20000901 ssssssssssssssssssssssssttttttttttttttttttttttttttttttt ssssssssss20000915 sssssssssssssssssssssstttttttttttttttttttttttttttt sssssssss20001001 ssssssssssssssssssstttttttttttttttttttttttt sssssss20001015 sssssssssssssssssstttttttttttttttttttt ssssss20001101 ssssssssssttttttttttttttt sssssssssss20001115 sssssssssttttttttttt ssssssssss20001201 ssssssssstttt sssssssss20001215 sssssssss ssssssss20010101 ssssssssss tttttsssssss20010115 sssssssssss tttttttttttsssssss20010201 sssssssssssss tttttttttttttttttssssssss20010215 ssssssssssssss tttttttttttttttttttttsssssssss20010301 sssssssssssssss ttttttttttttttttttttttttttssssssssss20010315 ssssssssssssssss tttttttttttttttttttttttttttttssssssssssss20010401 ssssssssssssssssssssssss tttttttttttttttttttttttttttttttttsssssssss

36.173 Science Goals:$ Tau: Instrumental Polarization Calibration/ Precision Assessment

. Tau: Polarization Efficiency verification (Astro/WUPPE overlap)Resonance line blanketing profiles => disk geometry/ dynamicsH Rayleigh polarization signature => disk ionizationNV, SiIV resonance polarization? => polar flow?

. Tau: Previous Spectropolarimetry

. Tau: possible FUV polarization effects

. Tau Simulated FUSP Observation

FUSP Optics Section

Experiment Design

FUSP Optics Section: View into aperture

FUSP Heritage

WISP (36.172UG) FUSPElectronics Detector Tek 1024^2 CCD WISP copy

Telemetry 2 Mbit dedicated WISP copyProcessor/ SW 6809/ C WISP copyCooling LN2 bleed/ TEC WISP copyGSE Rack/ Unix Workstations samePneumatics 1400 PSI bottle none

Optical Telescope Mirrors 2 10 in Hextek lightwt 1 20 inch Hextek lightwt Stressed Waveplate 8 in CaF2, programmable 1/2 in LiF, Fixed pressureBrewster 1 m ZrO2 flat 10 mm diamondGrating newCoatings Al/ MgF2 Al/ LiF (hygroscopic)Mechanisms 6 (2 doors, focus, wvplate

press/rot, shutter)2 (1 door, wvplate rot)

Structure 17", 220 lb, purged 22", 275 lb, evacuatedACS Standard Trkr Ball STRAP same ("ST1")

Target Trkr Off axis Ball STRAP Prototype UW Trkr ("ST2")Test Trkr Prototype UW Trkr Advanced UW Trkr ("ST3")Accuracy ±0.1° SameFOV 2×5° ZO: 12×17'; Sp 1×5'Hold ±0.5' ±5 arcsec

36.173 Experiment Flight Events

Nom 2-sig low

Event Time Src Altitude Altitude Dur Comment

Clock Start -60 Exp 1CCD Bias/ Dark -59 Exp 54Safe -5 Exp for powered fltBB Burnout 44.42 Veh 46.7 17.9CCD Bias/ Dark 48 Exp 54.7 26.5 92P/L Sep 64 Veh 88.5 63.1 40Open Door 75 Veh 110.4 86.8Arrive GS1 109 ACS 170.8 151.8On Target BetaTau 140 ACS 216.5 200.6 0 ACS hold 8 Exposures 140 Exp 216.5 200.6 100 ACS hold Slew to Zeta Tau 240 Exp 304.2 292.0 18On Target ZetaTau 258 Exp 310.4 297.9 ACS hold 24 Exposures 258 Exp 310.4 297.9 232 ACS hold Close Door 490 Veh 131.1 84.7 5Door Closed 495 Veh 121.8 74.0CCD Bias/ Dark 495 Exp 121.8 74.0 116Exp Power Off 611 VehChute Deploy 631 Veh

FUSP Experiment / Interfaces Outline

Mission Success Criteria

Comprehensive

1) Vehicle: 1000 lb to 300 km apogee minimum

2) ACS: experiment LOS pointing error < 0.1°.

3) Experiment: data on both targets obtained.

4) Payload recovered in good shape.

Minimum

1) Vehicle: 1000 lb to 290 km apogee minimum

2) Experiment: data on one target obtained.

Schedule

Needed from NASA:

Interface Connectors:ID Connector TypeUmbilical Cable P/J 900 DCMA-37PUmbilical F/O TBD TBDBall Tracker P/J 712A PT07SE-14-18SExperiment Sensor P/J 716 PT07SE-14-18PUW Test Tracker P/J 714 PT07SE-14-18PShutter Door P/J 756 PT07SE-12-10PIgnitor Housing P/J 757 PT07SE-14-19PPwr/ Telemetry P/J 940 PT07SE-22-55PAnalog Telemetry P/J 941 PT07SE-22-55SDoor Cable P/J 750 JT06-18-32S

Optics Bulkhead (Blank)

Optics Skin with blank Cooling and Vacuum Ports

Electronics Skin