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

User Tools

Trace: • 20180815_sevem_model90 • commanderissues • imagerteleconnotes20170807
imagerteleconnotes20171205

Differences

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

Link to this comparison view

Both sides previous revisionPrevious revision
Next revision		Previous revision
imagerteleconnotes20171205 [2017/12/05 13:42] – hananyimagerteleconnotes20171205 [2017/12/05 14:47] (current) – kyoung
Line 1: Line 1:
 ====== Telecon 20171205 ====== ====== Telecon 20171205 ======
  
-Attending:  +Attending:  Kris, Tom, Roger, Qi, Karl, Shaul, Brian
  
 Notes by : Karl \\ Notes by : Karl \\
Line 8: Line 8:
    * New sun shields, new alpha/beta? (JPL, UMN)    * New sun shields, new alpha/beta? (JPL, UMN)
      * {{::extension_shields.pdf|Last Week's Presentation}}      * {{::extension_shields.pdf|Last Week's Presentation}}
-     * {{::171130_pico_iso-front.jpg?50|New approach}} +     * {{::171130_pico_iso-front.jpg?25|New approach}} 
-   * Data Rate (Shaul) +   * Focal plane V3.0 (Karl) 
-   * Focal plane V3.0 (Karl?)+     * {{::sensitivity_updates_20171205.pdf|V3.0 status}}
    * Update from JPL     * Update from JPL 
-   * +
 === Notes:=== === Notes:===
 +
 +New sun shields, new alpha/beta? (JPL, UMN)
 +  * high angle tulip shields.
 +  * primary protected.
 +  * possible adjustments to alpha 30 or 35
 +  
 +Focal plane V3.0 (Karl)
 +  * 40K primary and 0.07% emissivity.
 +  * a 10% margin is included in these numbers given to the science team, just so they see less fluctuations.
 +  * Shaul: option to increase FP size and number bolos by 2x.  Keep this in mind.
 +    * Limits currently are data rate, see main imager wiki: posting/datavolume
 +      * 15k bolos give 3 Tb/day but DSN for 4 hours is 2 Tb/day
 +    * Kris: this is a stiff constraint for 10 yrs in future. Planck saw same type of limits evaporate during their planning.
 +
 +
 +Update from JPL
 +  * Roger: Wiring and thermal load w/ Chris Paine.  TDM and FDM.
 +    * FDM, has few wires to mK.  More complicated warm readout. (Shaul: more power, yes. not necessarily more complicated. )
 +      * Power usage 15k bolos -- 375 W for FDM
 +    * TDM, fewer wires. simpler warm readout
 +    * calculating heat load on mK from heat conduction and detector dissipation.
 +      * dissipation < 1 uW. not a problem.
 +    * wire count
 +      * x64 -- 1850 wires (TDM), with 350 mK buffer stage, few - 50 uW load on mK.
 +      * x128 -- 1140 wires, 3-30 uW load.
 +    * Next step, starting on FDM.
 +    * Peter Day is detector Team X partner.  Typically supportive of aggressive stance.
 +  * Brian: Joelle's model given to thermal analyst
 +    * from him: 
 +      * Just satellite drifting passively: space craft 260 K, primary 31 K.
 +      * Adding heat sources, coolers, etc. to refine numbers.
 +      * Shaul: need inputs to Goddard for ADR design.  Timeline?
 +        * Tom: need this by end of this week.
 +
 +Team X is December 19.
 +
imagerteleconnotes20171205.1512502938.txt.gz · Last modified: 2017/12/05 13:42 by hanany

Page Tools