Hubble Ultra-Wide-Field Imager (HUFI)

Transcription

1 Goddard Space Flight Center Hubble Ultra-Wide-Field Imager (HUFI) David Leckrone Senior Project Scientist for HST December 16, 2001

2 Goddard Space Flight Center 11/28/01 2

3 Goddard Space Flight Center 11/28/01 3

4 Goddard Space Flight Center HUFI (90 arcmin 2 ) (5.7 arcmin 2 ) (69 arcmin 2 ) (11.3 arcmin 2 ) 11/28/01 4

5 Field of View FOV Footprint at CCD FPA 40 4K 4 K x 4K K CCD s (3 each) (3) FOV at CCD CCD 1 CCD 2 CCD 3 30 y image (mm) 90 square arc minute FOV X image (mm) hs tfull fd.14,11/14/01, p /28/01 5

6 Optical Schematic M3 Mirror Pupil M1 Mirror Filters, CCD Shutter Location CCD FPA M2 Mirror Radial Pickle Pick Off Mirror (POM) HST OTA MM HST Full Field.14, 11/12/01, p44-45, 90 Scale: 0.09 raw 14-Nov-01 11/28/01 6

7 Goddard Space Flight Center Geometric ray trace compared to two-pixel and four-pixel width scale-bars shows a well-corrected design. FIELD POSITION 0.35, ,0.130 DG FIELD POSITION 0.35, ,0.130 DG 0.54, ,0.216 DG 0.54, ,0.216 DG -0.79, ,0.130 DG -0.79, ,0.130 DG -1.00, ,0.165 DG -1.00, ,0.165 DG 0.79, ,0.130 DG 0.79, ,0.130 DG 1.00, ,0.165 DG 1.00, ,0.165 DG 0.00, ,0.130 DG 0.00, ,0.130 DG 0.00, ,0.233 DG 0.00, ,0.233 DG 0.00, ,0.202 DG.300E-01 MM 0.00, ,0.202 DG.600E-01 MM DEFOCUSING DEFOCUSING /28/01 HST Full Field.14, 11/12/01, p44-45, 90 HST Full Field.14, 11/12/01, p44-45, 90 7

8 Optical Performance HST Full Field.14, 1 1/12/01, p44-45, 90 raw 19-Nov (0.000,0.202) DEGREES (0.000,0.233) DEGREES (0.000,0.130) DEGREES (0.165,0.165) DEGREES (0.130,0.130) DEGREES DEFOCUSING ENCIRCLED ENERGY E E E E E E E E E E E-01 DIAMETER OF CIRCLE (MM) Diffraction PSF encircled λ=632.8 nm for center field and 4 other field 11/28/01 positions show that PSF is diffraction-limited and is uniform over full FOV 8

9 Goddard Space Flight Center 11/28/01 9

10 Instrument Layout Filter Mechanism CCD Heat Pipes Calibration Door Mechanism M3 M1 M1 Corrector Mechanism Shutter Mechanism Pick Off Mirror 11/28/01 10

11 Instrument Layout FGS Enclosure Side Optical Bench Strut Point C (Point B Opposite Side) Radiator CPL Saddle To AS Radiator 11/28/01 11

12 Instrument Layout M2 M2 Support FGS Enclosure 11/28/01 12

13 Goddard Space Flight Center +V2 SIDE OF HST NCS RADIATOR FGS3 BAY 11/28/01 13

14 HUFI Design Features All-Reflective Design Four surfaces one flat, three powered Well-Corrected Aberrations Wavefront error to waves rms at 632.8nm Flat Focal Surface Requires three 4Kx4K CCD s similar to ACS and WFC3 detectors Cooling Via HUFI External Radiator Plus Coupling To NCS Radiator Replaces FGS #3 Without Compromising Current Pointing Performance Does Not Interfere With Other Instruments Amenable to parallel observing Follow-up observations with WFC3, COS, ACS, STIS 11/28/01 14

15 HUFI Scientific Performance FOV 90 arcmin 2 (8xACS, 16xWFPC2) Pixel Scale 0.10 arcsec (same as WFPC2) Sensitivity Comparable to ACS in I-band, 5x WFPC2 in I-band Discovery Efficiency 8xACS, 80xWFPC2 SNe Ia Discovery Rate - ~1 per day with follow-up 11/28/01 15

16 POTENTIAL OBSERVING STRATEGY 3-6 Month campaigns dedicated to high galactic latitude fields Deep exposures with WFC3, COS, ACS broken into multiple visits HUFI parallel exposures for free SN detected in HUFI fields followed with other HST instruments STIS spectra for redshifts and classifications up to z=1.2 WFC3 near-ir images and grism spectroscopy up to 1.7 microns ACS higher resolution images for host galaxy morphology 11/28/01 16

17 200 SNe la 200 SNe la + σ ΩM = 10%

18 200 SNe la 200 SNe la + MAP + σ Ho = 10%

19 HUBBLE MISSIONS SM3B SM4 End of Mission? SM1 SM2 SM3A Gyros Advanced Computer Fine Guidance Sensor Wide Field Camera 3 Fine Guidance Sensor Aft Shroud Cooling System Batteries Advanced Camera Gyros Solar Arrays Power Control Unit NICMOS Cooling System Launch! Imaging Spectrograph Near Infrared Camera Fine Guidance Sensor Wild Field Planetary Camera 2 COSTAR Gyros Solar Arrays /28/01 19

20 Goddard Space Flight Center RETIREMENT OPTIONS FOR HST One Shuttle flight allocated to HST after Servicing Mission 4 in 2004 Current baseline plan is to return HST to the ground in 2010 Exhibit in National Air & Space Museum Requires partial disassembly and disposal of multiple pieces in orbit (e.g. solar arrays, external radiators, possibly instruments) 5 EVA mission Requires HST to be stable and commandable Less than 50/50 chance that HST will function to 2010 Alternative option Light servicing mission in 2007 instead of 2010 Maximizes probability of zero downtime between HST and NGST Attach propulsion module to HST for end-of-mission controlled reentry Provides possible opportunity for new instrument, e.g. HUFI 11/28/01 20

21 9/10/01 HST Reliability Indicator from the Refined Aerospace Corporation Model 1.0 Probability Elapsed Time - Years Probability of HST Science Operations vs. Time Since Last Servicing Mission 11/28/01 21

22 Goddard Space Flight Center SUMMARY We ve identified an instrument design which provides a major increase in FOV compared to prior HST cameras A systematic campaign should yield ~1 SNe per day with follow up provided by full suite of HST instruments Flight opportunity requires change in current baseline retirement plan for HST and willingness of Code S to support a new HST instrument 11/28/01 22

23 Thermal Block Diagram 40 watts to AS HUFI Radial SI Existing Inserts 90 watts electronics to modified door radiator using HPs New Radiator/ Door 120 watts to NCS Radiator using HP/VCHP to carry heat from CEB and CCDs NCS Radiator 11/28/01 23

24 Power Flow Total estimated power requirement of 250 W 60 watts From HST HUFI Radial SI Diode Box Auxilary Power Ports 190 watts from NCS Radiator auxiliary power supply NCS Radiator 11/28/01 24