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--- imagerteleconnotes20171010 [2017/10/10 13:56] – kyoung
+++ imagerteleconnotes20171010 [2017/10/11 10:31] (current) – kyoung
@@ Line 1: / Line 1: @@
 ====== Telecon 20171010 ======
-Attending:  \\
+Attending:  Jamie, Brian, Julian, Kris, Shaul, Karl, Qi, Roger, Jeff F.
 __Agenda:__
-  * optical systems: large aperture and small aperture options (Qi)
+  * {{:large_and_small_apertures_20171010.pdf|Large and small aperture presentation}}
-  * noise model and focal plane options (for large and small apertures) (Young)
+    * optical systems: large aperture and small aperture options (Qi)
-    * {{:large_and_small_apertures_20171010.pdf|Large and small aperture presentation}}
+    * noise model and focal plane options (for large and small apertures) (Young)
   * Scan pattern (Gorski, Delabrouille)
+__Notes:__
+Status of optics (Shaul)
+  * Matrix of larg v. small and open v. crossed.
+    * large, open is baseline.  Noise, weights, etc calculated and posted on Imager wiki page
+      * current version is un-optimized optics.  **A/I** UMN to use coma corrected and optimized open dragone. Recalculate noise.
+    * small open and crossed designs work. Noise is calculated.
+      * What alpha, beta angles are allowed?  **A/I** UMN to investigate.
+      * Motivation is to have a cost savings option
+        * Question from group: Does cost truly scales with aperture? Or is complexity the bigger issue.
+          * focal plane size, detector count, readout and power demands, etc. likely bigger driver.
+          * Suggested: Are there other rocket options? If the payload is smaller this could be a savings location.
+            * Likely that Falcon 9 is only choice.
+    * large, crossed dragone still has sidelobe problems.  1.2m version is promising.  A work in progress.
+  * Note: Al says PIXIE can observe with same scan strategy as imager.  Kris would like to see the details of how this works.
+cm systems (Karl/Qi)
+  * 3x hit in resolution
+  * 4 K and 30 K systems.
+  * 4 K gives better performance than baseline at high frequencies, ~> 300 GHz.
+  * 30 K is worse at all frequencies.
+  * Is > 300 GHz sensitivity very useful?
+    * May not increase dust removal accuracy much.
+    * High frequencies are largely for extra-galactic science and galactic dust science.
+      * The 3x lower resolution may make these unappealing anyway.
+        * General opinion that the resolution loss is a high price to pay.
+        * Makes the science less appealing.  This makes it less likely to appeal to Decadal Panel
+  * open dragones (30 K and 4 K) are smaller and fewer pixels than baseline.
+    * likely a cost savings.
+    * 4 K assumes cooling an additional ~1m mirror, which adds cost.
+Scan (Kris)
+  * Higher spin rates a concern. Data rate may become an issue.
+    * Past work by Amy said telemetry not an issue.  May need to be revisited.
+  * possible spin rates in the 1-3 RPM range.  Being studied at JPL, Amy organizing.
+    * needed for 1/f, data rate, ect.
+  * **Kris** to present concerns with scan next week.

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