Go to the U of M home page
School of Physics & Astronomy
Probe Mission Study Wiki
imagerteleconnotes20171107

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revisionPrevious revision
imagerteleconnotes20171107 [2017/11/07 15:50] kyoungimagerteleconnotes20171107 [2017/11/07 16:13] (current) kyoung
Line 25: Line 25:
 Prep for Team-X meeting in mid-Dec.  They will cover telescope + focal plane + Cooling = instrument Prep for Team-X meeting in mid-Dec.  They will cover telescope + focal plane + Cooling = instrument
   - Optics of 1.2m vs 1.4m.  1.4m open has better resolution and sensitivity.   - Optics of 1.2m vs 1.4m.  1.4m open has better resolution and sensitivity.
-  - No glaring issues with open, even though it is less traditional. +    - No glaring issues with open, even though it is less traditional. 
-  - Brian: Does baffle create sidelobes? +    - Brian: Does baffle create sidelobes? 
-    - Shaul: Goal is to do a basic GRASP calculation to figure this out+      - Shaul: Goal is to do a basic GRASP calculation to figure this out. In contact with Brad Johnson 
 +    - Karl will calculate sensitivity of crossed at 4K. Maybe something to pursue. 
 +  - Should we go to Team-X with multiple options? 
 +    - Al: They tend to split their time evenly amongst options they are given.  Would need to make clear what our focus is if we bring multiple options.  Prefer taking just 1 workable option.  It's time to finish with optics and move focus to other issues which need work. 
 +      - Shaul: Our case is 1 basic framework with options being changes on top of this. 
 +      - Al: Team-X can do this if the scope is made clear in pre-session.  However may not be most effecient use of Team-X time/expertise. 
 +  - Gathering telescope quotes: 
 +    - Brain, JPL, and Shaul. 
 +    - Components are fraction of cost.  Majority of cost is testing. 
 +      - Al: WMAP testing was cold photograms, warm beams, accounted for cooling deformation with models 
 +      - Jacques: Planck testing was sidelobes warm, deformation and alignment as mirror cooled, no end-to-end cold test with flight system. 
 +        - CORE estimate, very unofficial, was $10-20 million 
 +  - Cooling: 
 +    - Chris Payne working on strategy 
 +    - continuous ADR cost from Goddard slow to come in.  Working on this. 
 +    - Possible single shot ADR from Europe. planned for Athena mission. 
 +      - Jacques: Same group is developing continuous ADR.  Probably low TRL currently.  Jacques willing to connect people if needed. (not needed currently) 
 +    - Roger: Will send around BLISS ADR system. Was a bench test system at JPL. 
 + 
 +Skip Mission discussion for now, deadline in March although work needs to begin. 
 + 
 +Systematics 
 +  - What do we need for 1/f? Sidelobes? Gain stability? pol angle calibration?  And how to simulate this. 
 +  - Sidelobes: Estimate in GRASP via Brad J. 
 +    - Jacques: This job is very large and approximations are often done. 
 +    - Shaul: Plan is to do a course model to get representative levels. 
 +  - Julian: Simulation pipelines exist to take scan + sidelobes, produce maps, and estimate systematic errors in parameters. 
 +    - need proper inputs 
 +    - simulation of mitigation of sidelobes is harder.  Need a way to estimate your sidelobes and your mitigation method separately, then combine in simulation. 
 +    - typically simulate each systematic separately, then do 1 sim with all systematics to see overall effects. 
 +      - Shaul: this can get infinitely complex. We'll focus on the 3 issues highlited by systematics group first. 
 +    - All these are doable, suggestion: Do 4-5 locations on focal plane. 
 +      - Jacques: do 4 detectors simultaneously so you get 1 Q and 1 U measurement.
  
  
imagerteleconnotes20171107.1510091427.txt.gz · Last modified: 2017/11/07 15:50 by kyoung