Solar-B EIS

1
Solar-B EIS

• Steering Committee meeting
• 27th May 1999

2
The position last February

• Design dichotomy
• effort in UK slow or stalled
• science goals not well articulated e.g.
  wavelength range choice
• Interface management unclear
• Schedule and costs unclear

3
Kick-off MeetingISAS, March 8-13 1999

• Mission Philosophy
• Organisation
• Master Schedule
• Spacecraft Overview

4
Design of EIS

• Cassegrain or OAP?
• Technical drivers - feasibility, costphysical
  resourcesdisturbance torque- for Structure,
  Optics, Detectors, Elec.
• Line lists
• Effective areas - useful lines in QS, AR, Fl.

5
Management Plan

• Decision making
• Science - PIs Project Scientist Consortium
• Program - PM (MSP) PIs
• Engineering - SDT
• Decision dissemination
• Science Technical email lists (points of
  contact)

6
Design of EIS (2)

• Value of Spatial Resolution
• Value of Throughput
• Decision-making panel ISAS, NAOJ, NASA, NRL,
  PPARC/MSSL
• Throughput (OAP) given priority

7
on from there

• NRL asked to propose an OAP concept
• with two wavelength ranges170-206 Å250-290 Å
• on the same detector, non-overlapped, if
  possible (implies two grating surfaces)
• keep high throughput,improve spatial resolution
  if possible

8
The new NRL/GSFC designs

• NRL/MSSL series of teleconferences- discuss
  progress and direction of optical design-
  also an opportunity to learn lessons from
  SOHO/LASCO
• became clear that engineer-level round-table
  interaction needed Þ NRL opto-mechanical
  engineering meet.

9
preferred design EIS-7T

• one of a series of optimisations
• small grating - low risk
• toroidal grating - more vendor choice
• magnification - short spectrometer section
• add telescope length - improve spatial
  resolution
• details published by FTP 7 May 99

10
Optical properties

• Nyquist-limited - spot sizes closer to detector
  pixel size
• effective detector pixels governed by charge
  spreading (R. Stern investigations)
• large effective field-of-view - 1000

11
UK response

• BU - structural concepts
• MSSL - camera head concepts
• swift drawing interchange
• mechanisms - mass? power? placement?

12
Opto-mechanical engineeringmeeting, NRL 17-18
May 99

• US, UK, J involvement
• review NRL/GSFC work to date
• approve the criteria and results
• review subsystem technology designsitems
  connected with main instrument
• suggest ideal placement
• iterate before BU consortium meeting

13
The main Actions

• NRL/GSFC- reduce lengthby 10 cm- issue new
  optical layout- denote volumes which must be
  separate
• 1st June

• BU/MSSL- iterate structural concept, use
  sectional construction- include radiator
  placement- camera update
• 14th June

14
Interface Management

• System engineering - an MSSL responsibility to
  lead, but need help/experience from team
• Timetables () - e.g. mechanical thermal models
  - aiming for Phase B !!
• Interface list - ()
• Spacecraft Interfaces ()

15
Panels - Meetings - Minutes

• Consortium
• Science
• Oversight of technical progress
• archive EIS-meet-cons-YYMMmins -YYMMagen
• System Design Team - includes NRL telecon
• Technical
• Sys Engineering, Budget, Schedule
• EIS-meet-sdt-minutesX EIS-meet-sdt-tcXXXX

16
The position now ...

• Major design decision made
• UK work going ahead
• Science goals getting clearer
• Wavelength ranges selected
• Interfaces clearer - need more work
• Planning (schedule /costs) - improving