Telecon Notes January 9, 2019

Attendance: Shaul H., Marcel S., Alex vE., Amy T., Tim P., Jacques D., Nick B., Dan G., Charles L. (Many people at AAS)

Notes by: Karl

• Additional Telecon on Friday at 3 pm Central Time = 4 pm Eastern; 1 pm Pacific.
• Brief update on report outstanding items
  • implemented details contributions by Marcel, Jacques, Jim (clusters)
  • Few updates outstanding in Inflation (Fig. 2.1; 2.2; ES)
  • Need review of what's stated in SOs
• Why PICO now?
• Finalizing Cover Art
  • Smaller PICO (< = 0.5!)
  • Thicker dotted lines
  • End of Dark Energy line: extend inward by ~0.5 in (should be longer than neutrino)
  • Dark matter: make fading same as cosmic birefringence
  • Cluster evolution extend inward by 1 in (should be longer than galaxy evolution)
  • Luminous sources: move a bit outward to coincide with center of white circle.
• Control of Systematic Uncertainties
  • 12,996 independent I,Q,U maps
  • 10 sky surveys
  • multiple time scales: 1 min, 10 hours, 6 months

Next telecon Friday 3pm CST

Brief update on report outstanding items, SH: In fairly good shape.

• implemented details contributions by Marcel, Jacques, Jim (clusters)
  • SH: Lots of good review from Marcel. Got Jacques's foregrounds comments.
• SH: Tim is cleaning up details of latex and grammar
• Few updates outstanding in Inflation (Fig. 2.1; 2.2; ES)
  • Waiting on updates from Raphael These are the only items left to complete science section.
• Need review of what's stated in SOs. Ensure consistency. Checks needed by SO authors as well as unrelated folks.
  • Checks of STM (Table 1.3) over next 1-2 days.
  • S01, S02. Inflation. SH will write to Raphael to have him check Dan G. check
  • S03, S04. Neutrinos, Neff. Nick will check Dan G. check Neff
  • S05. Reionization. Alex will check
  • S06, S07. SH will ask Dave, Laura, and a less tightly connected galactic member.

Why PICO now?

• SH: Exec summary gives a strong science case. But 'why now' is not so obvious. Any input for this argument?
• CL: Question is, “why isn't it better to wait for S4, SO, and similar”.
• AT: Some missions have to fly now (e.g. Starshade because works with WFIRST). PICO benefits from coming closer on the heals of Planck. Can recycle the manpower.
• AT: Also mitigate the “Let's wait until there is more information” argument.
• JD: Much work is going into CMB now. We should support that.
• CL: UV or X-ray astronomers may say they have waited 20-30 yrs for another mission, not the 10-15 since Planck. But timing argument always fails at some level. The CMB won't disappear in 5 years.
• CL: but key argument is where you get the most science for the money. CMB has been a very good value.
• SH: Sometimes there is a good reason to wait (technology, further data, etc). Sometimes there is no reason to wait, which means there is a reason to launch now. We have learned from Planck, so now time to push forward.
• CL: in 2010 there where 2 reasons to wait. 1. Planck. 2. ground experiments were ramping up. what if they see a hint?
• CL: Planck has flown and is fully analyzed. There is no other way to step forward on full sky information than another space mission.
• CL: Not a strong counter to argument 2. There are still new ground experiments coming up all the time.
  • JD: Can we argue that what is learned from ground won't change mission? CL: That's a good point. There are many things PICO can do that can't be done from the ground. Like this argument. The largest angular scales can't be done from ground/sub-orbital.
    • SH: Should be little careful about things being impossible at largest angular scales. CLASS is trying to get EE on largest scales. Got some push back from Bennett.
      • CL: “Can't do from ground” is a quantitative statement. The ground can't get as far as PICO.
  • MS: Could argue that 2030's will be stuck without PICO. because of the things you can't ever do from the ground.
  • AT: Is the argument? “Other people will have to wait if PICO doesn't fly. Since PICO enables other science (tau, cross-correlations, . . .).
• SH: Is it timely to say that this is the time for a space mission? We are scaling up to massive collabs on the ground. So scaling up to a space mission makes sense.
  • CL: Ties into JD's argument about how would PICO change with new ground data. S4 is basically the final ground experiment, another factor of 10 is just too expensive. So we have to go to space. Starting now on PICO then makes sense.
• JD: Striking that in US and around world many groups are putting together proposals that are similar to PICO or part of PICO. Suggests interest and options for international partners.

Finalizing Cover Art

• Smaller PICO (< = 0.5!)
  • SH: Strong votes over email.
• Thicker dotted lines
• End of Dark Energy line: extend inward by ~0.5 in (should be longer than neutrino)
• Dark matter: make fading same as cosmic birefringence
• Cluster evolution extend inward by 1 in (should be longer than galaxy evolution)
• Luminous sources: move a bit outward to coincide with center of white circle.
• CL: Still think this is very cool.
  • SH: originally came from Cynthia Chang via Alex. Shaul reached out and offered recognition. She passed. She had got the idea from somewhere else as well. But thanks to Alex for idea.
• ALL: No other comments.

Control of Systematic Uncertainties. SH: some basic simple and compelling statements on systematics control.

• examples: 12,996 independent I,Q,U maps; 10 sky surveys; multiple time scales: 1 min, 10 hours, 6 months – all provide large redundancy in the data. This was by design. Some of this existed for Planck , and was important, now we have even more.
  • JD: A bit of a weakness, the 12996 maps are high noise so you can't just look at single bolo maps.
    • SH: True. the 12996 was to show multiplicity of options. can make 4 maps of 3000, 2 of 6000, etc.
    • CL: But looking pair by pair at bolos can be done on T for calibrating between detectors effectively. This is possible for many combos in PICO. And this can be done on relativity short timescales. JD: True. Key point was that you won't detect systematics at the full mission level from 1 detector. CL: yep, all agree.
  • JD: for redundancy with Planck. There was only small area of the sky covered in multiple days. PICO is different.
    • SH: Now 50% of sky in 2 weeks. This does help. But we need to take argument a step further to say what you do with that 50%.
    • JD: Then repeat the same (almost) 50% 2 weeks, 4 weeks, 2 months later. Very good redundancy.

JD: What is final endorsement deadline?

• SH: Anything this week and early next week is fine. AFter that probably not. Want this report done.

Meeting Friday, then final telecon next Wednesday.