Telecon Notes Oct. 24, 2018
Attendance: Nick B., Rafael F., Amy T., Alex v., Colin H., Tim P., Charles L., Jim B.
Notes by: Karl Young
Agenda
Notes
Raphael's earlier forecast gave sigma® = 2e-5; we made it 2.5 times larger and used 1e-4 (2σ)
Stephen's Forecast:
components: sync+dust
delensing option: iterative delensing CMBxCMB
σ(τ=0.066)=1.95e-03
σ(h=67.74)=8.41e-02
σ(As=2.142e-09)=7.43e-12
σ(r=0.0)=9.41e-05
σ(Ωch2=0.1188)=2.11e-04
σ(ns=0.9667)=1.08e-03
σ(Ωbh2=0.0223)=1.86e-05
effective level of foreground residuals, reff = 8.74e-07
degradation of the noise after comp. sep. = 1.10e+00
noise in the cleaned CMB map [uK-arcmin] = 9.02e-01
These forecasts were run using the CMB4cast Fisher matrix code (http://portal.nersc.gov/project/mp107/index.html, Errard & Feeney et al.), assuming access to T, E, B and d information, with the deflection estimated using the iterative EB estimator. The code assumes Planck-2015-level synchrotron and dust foregrounds, forecasting the experiment's ability to clean these foregrounds using a parametric maximum-likelihood approach, assuming the foreground spectral indices are constant on patches of size ~15 degrees across (N_side = 4). This is all probably a little out-of-date, being based on the Planck 2015 results and cosmology, but it doesn't seem to give a significantly different answer to Raphael's code (and I can rerun with a different tau if you'd like).
SH Tenerife 2018 Presentation
Current Roster of Reviewers
Mike Shull, Kathy Romer, Jonathan Feng, Michael Strauss, Wick Haxton, Keith Olive, Larry Rudnick, Liliya Williams, Martin White, Lyman Page, Masashi Hazumi, Adrian Lee, Scott Dodelson, Chuck Bennett, Ed Wollack, Paolo deBernardis, Bruce Draine
Minutes / Notes during telecon
Current Version of Report Draft ready by next telecon!
New site for other supporting material. PICO Mission Website
Quoting r constraints (see some relevant material in notes, above)
r < ?? (95%)
Used RF prediction times 2.5 that didn't include spectral index variation. 1×10^-4
Have Stephen Feeney predictions. Also Fischer. Does account for some more foregrounds. spatial variation on nside=4 scales. used v4.1 noise. got r 10^-4.
SH: What do we put in report?
CL: can't say this is finalized. emphasize the need for more foreground and systematics work.
CL: 10^-4 is good goal. science is written around this. Then be candid that this hasn't yet been demonstrated, but we believe it is achievable. More work needs to be supported. This is another tech development area. We aren't ready to get 10^-4 now, but will be ready at time Probe would be happening in ~2023 or so.
RF: That makes sense. all the current numbers come with caveats.
SH: Other path: at small areas of sky (few %) S4 demonstrated r 10^-3. PICO has many such areas.
RF: but most not as clean as S4. so can't just scale to 60%.
SH: Yes, but some patches are as good as S4's. 3-10? RF: could make a scaling arguement, but wouldn't get order of magnitude.
RF: like Stephen's forecasts. Although S4 didn't clean in map domain to that level. We know PICO can do order of magnitude 10^-4, but don't know if 1×10^-4 or 5×10^-4.
SH: Setting a goal makes sense. But also needs to be some statement about what we know now. May know more about map based by December. What other definitive things can we say now?
RF: that sounds fine as long as our current level of uncertainty in current predictions is explicitly included.
SH: scaling from S4 by # clean patches (increase in number of modes) makes sense. Other places we can quantify in next few weeks? SH, RF will follow up on this scaling
Report
Inflation
Figures (Label lensing? show noise? remove data point labels, change prediction level to 5e-4? show Goncharov type models?)
Connection to lensing and Alex's part? SH: nothing in this section now?
Non-Gaussianity forecasts by Marcel. In page 13. SH: should this be highlighted here?
RF will add text on the above points to text
Fundamental particles. DG has added material. Section has DM, nuetrinons, . .. Needs references fixed and section trimmed. Has plots from Alex to add. Also plots from Vera deciding to keep or not. DG cleaning up now
RF: probably both can be summarized in words. DG: yeah, signature isn't needed.
SH: worth pointing out that this is on the only constraints at low DM masses. Could add direct detection constraints to this figure. Show that PICO is unique.
DG: have to think if there really are no other constraints. Landscape is complicated. May be other limits depending on dark matter models.
SH: key point is that if we include this figure the comparison to direct detection is illuminating. DG: yeah, this is a relevant connection. and would be reason to have this plot. Still not sure if the figure is needed. DG will talk with Vera and decide on figure. SH/DG talk offline
SH Added 'Fundamental Fields' (PMF and birefringence) anyone wants to review?
Extragalactic
Galactic – Dave Laura have new text. only a bit too long. nearly final.
Legacy
Complementarity
Foregrounds
Systematics
Quick email turnaround and phone conversations appreciated!