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--- imagerteleconnotes20180228 [2018/02/28 13:10] – created kyoung
+++ imagerteleconnotes20180228 [2018/02/28 16:27] (current) – kyoung
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 ====== Telecon 20180228 ======
-Attending:
+Attending: Bill, Tom, Kris, Hannes, Shaul, Karl, Qi
-Notes by : \\
+Notes by : Qi\\
 === Agenda===
-  * Telescope I+T (Tomo and Bill)
+  * Telescope and Instrument I+T (Tomo and Bill)
     * {{::20171212_picoi_t_v002.pdf|Tomo's slides}}
     * {{::plancki_t_jones_20171212.pdf|Receiver, Bill Jones}}
-  * Instrument I+T (Bill J.)
+    * {{::iandt.pdf|I&T, PICO specific, Bill}}
   * Planck decontamination, cooling, and in-orbit checkout
   * Focal Plane configuration + ADR location + GRASP update (Karl)
     *  {{::focalplane_update_20180214.pdf|Focal plane slides}}
     * Adjusted system to alpha = 30, beta = 65.
-      * ADR position image:{{ ::180222_pico_beta65deg_karl_edits_adr.jpg?100|}}
+      * ADR position image:{{::180222_pico_beta65deg_karl_edits_adr.jpg?100|}}
-    * GRASP slides {{:systematicswg:telecons:2018-02-14:grasp_status_20180214.pdf|status 1 week ago}}
+    * GRASP quick update.  Slides just in case: {{::grasp_status_20180228.pdf|grasp_status}}
 === Notes ===
+  * **Planck decontamination, cooling, and in-orbit checkout**
+    * Someone needed to write ~ 1 paragraph.  Charles Lawrence suggested.
+    * From Bill:
+    * CPV (commissioning and performance verification) at L2
+      * Telemetry checkout, cryogenic check, normal receiver operation etc.
+      * For PICO, the best mode needs to be decided; spinning or spinning + precession; we have to spin to stabilize. Different spin rate is something interesting.
+    * baking primary during launch to remove water not part of CPV
+    * Passively cool, during the flight to L2
+  * **Telescope and Instrument I+T (Bill)**:
+    * **Receiver**
+      * Planck, did not include a lot of stuff prior to 2005
+      * overview in page 1
+      * some periods below:
+        * Sep, 2005
+          * Cryogenic chain, delivered and tested
+        * Mar, 2006
+          * HFI focal plane integration, 2 K bath, 100 mK, less than a week of testing; primary goal, show cryogenic works; gross noise check
+        * May,2006
+          * cryogenic, photometry, cooling down to 40 K, measuring surface separation
+        * July,2006
+          * same run as above, to do calibration, 20 day period, not fully integrated system, 2K to 100 mK, nothing at room T
+          * Much longer time is better, 20 days is really risky
+        * may,2008
+          * final cool down, only time of fully integrated test
+          * not designed to do any useful testing, cold load in front of focal plane, T is not stable, so no noise testing
+        * may 2009
+          * launch
+     * **I&T, PICO specific**
+      * counting back from launch, overview
+        * T-4 years: devices level detectors
+        * T-3years: proving sub-k cryogenics, maybe spectroscopy and noise testing;
+          * the sooner you get integration tests, the better; example: problem related to wiring, you won’t know until you get the full integration
+          * Planck did not have HFI+LFI fully test; 100 mK, 4K, more natural to sepaerate
+          * Cryogenic photogrammetry of telescope and truss, very important for Planck
+        * T-2 years: entire cooling chain
+        * T-1years: require a proper chamber
+      * Details:
+        * T-3 years:
+          * full focal plane, not the entire cooling chain
+          * due to warm primary, be careful of how to mimic background operational conditions at L2
+          * 3 mK fluctuation on 3K, heater, pump helium back; 10% percent level; as if we are observing CMB, for non-linearity etc.
+          * no mirrors, find the right chamber, ~meter level, time being cold should not be less than 1 month
+          * Polarimetric calibration ● Spectroscopic calibration
+          * two runs because of some expectation of something not working
+          * Planck never measured Spectroscopic with mirrors
+          * Planck Polarimetric, used those obtained during device level testing; it’s tricky to do it with fully integrated system. Very difficult measurements
+          * Cryogenic photogrammetry of telescope and truss [Large 300-40K chamber, 1 mo], may have to do mirrors separately for PICO, 30K, 4K
+        * T-1 years:
+          * cool the whole thing down, long run
+          * Because of TES, optical loading, to see Psat
+          * If we convince ourselves that we can do Polarimetric calibration ● Spectroscopic calibration on the whole system, we should
+          * Shaul: depending on the size of chamber
+          * Bill: do the math, and believe device level testings
+          * Planck was lucky, given the limited time of fully integration testing.
+          * Shaul: polarization modulation efficiency, one would calculate well based on the testings without mirrors.
+          * Bill: angular calibration, independent may be demanding.
+          * constrained bandpass mismatch, using data itself. It’s a big question to reach r<10^-4.
+          * 2 month is the tight. sort of Planck schedule. better to add 1 month to do testing, not sure the cost.
+          * in flight correction of HFI, the challenge is it’s difficult to do spectroscopy tests on the whole, which are in fact dependent on the whole system.
+        * cost, driver, 3 level of testing set ups
+          * modest, device, institutions
+          * large, full focal plane, calibration equatment needed, time needed
+          * 3rd, big chamber, fully integrated, time and calibration we want to test.
+          * Timing is likely to drive the cost

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