Campuses:
PICO Report
Focus over the recent period has been on writing our 50 pg report. It is due to NASA by the end of Dec. 2018. NASA will forward this report to the Decadal Panel. If you would like to contribute by generating forecasts or writing sections of the report please contact one of the Sections' leaders listed below. We may also ask some of you to review specific sections.
Our internal deadline is to submit the report to external reviewers by Nov. 1. Please nominate, or self-nominate reviewers by sending an email to hanany@umn.edu.
Section Leaders: Fundamental Physics - Raphael Flauger, Dan Green Extragalactic Science - Nick Battaglia, Colin Hill, Complementarity with other astrophysics surveys - Marcel Schmitfull Complementarity with other CMB projects - Charles Lawrence Galactic Science - Dave Chuss, Laura Fissel Legacy Surveys - Gianfranco de Zotti Component Separation - Jacques Delabrouille Systematic Effects - Brendan Crill
CoSigning the Report
When the report is mature we will circulate a final draft and you will have an opportunity to CoSign before it is submitted to NASA.
The Report and Decadal Science White Papers
As you may know, there is a project-independent effort ongoing to write and submit Science White Papers to the Decadal Panel. The deadline is in early January. This effort transcends PICO, CMB-S4, or other specific projects. Hence, the PICO report is separate. We expect that NASA will forward the PICO report to the Decadal Panel in conjunction with delivery of other project-related white papers in mid-2019.
Instrument Update
The architecture of the instrument hasn't changed since early summer. We now have a final required specifications and final best case performance estimate (also known as 'goals'). The one number summary is that the required depth is 0.87 uK*arcmin, and goal is 0.61 uK*arcmin, both are for full sky coverage.
Final Engineering Review and Cost Estimate
Our colleagues at JPL will finalize the mission's engineering documents by the end of October. Some of the contributions will enter into the report, others will accompany the report as a set of slides. As reported in the past, the mission is costing within the $1B cap, with some margin.
NASA has recently changed the way it plans to review JPL's cost estimate. The new process is still in flux. There will be more information in the next update.
Instrument and Mission Design
In March we had our second TeamX-Instrument Session and the TeamX-Mission Session (see more information about TeamX session below). They were both successful. No red flags were identified with either the instrument or the overall mission design. The JPL cost estimators concluded that we fit comfortably within the cost window. Our engineering designs are now relatively mature and we don't expect significant changes. The imager has nearly 13,000 bolometers; there are 21 frequency bands spread between center frequencies of 21 and 800 GHz; the telescope has an aperture of 1.4 meter giving resolution between 38 and 1 arcmin across the frequency bands; the mission includes a 5 year survey giving a best case estimate map depth near 0.6 uK*arcmin.
We are finalizing the science requirements and required map depth, which is expected to have a somewhat larger value.
There will be a final wrap-up session during which the engineering team will finalize its engineering and cost report. This engineering report will accompany our final report to NASA.
[During a 'TeamX Session' a team of engineers is addressing a number of mission design issues such as overall instrument design, thermal engineering, telemetry, trajectory, and operation. There are two types of sessions, one concentrating on the instrument - the telescope, focal plane, readout, and the cooling chain - and the other concentrating on mission aspects, which includes the spacecraft, the attitude control, the telemetry, and the power systems, among others.]
Science Workshop
We had a very useful 2.5 day workshop in Minneapolis, during which we surveyed the broad science achievable with PICO. We have also outlined the structure of the report and discussed preparations for the decadal panel.
Many thanks to all the contributors.
All the talks are posted on the wiki page.
Report and The Decadal Panel
We are entering the final stage of the study. During this stage we will finish the forecasting work and write the report. The report is due in December 2018.
We have just recently heard that the Decadal Panel will proceed according to the original schedule. A message from Paul Hertz, NASA's Astrophysics Division's director, is posted on the wiki.
Message from Paul Hertz
Colleagues -
At the National Academies Space Science Week in March 2018, Thomas Zurbuchen (NASA Associate Administrator for Science) charged the astronomy and astrophysics community with considering whether the upcoming Decadal Survey could be ambitious and forward looking in the context of the unresolved challenges for the James Webb Space Telescope (launch date is delayed and under review) and WFIRST (proposed for termination in FY2019 budget request). He suggested that one could delay the Decadal Survey until these issues are resolved, and he asked the community to consider whether there was an alternative. He repeated his question at the April 2018 meeting of the Astronomy and Astrophysics Advisory Committee and the May 2018 meeting of the Space Studies Board.
NASA's Program Analysis Groups conducted a survey of the astrophysics community to gauge community thoughts (https://cor.gsfc.nasa.gov/copag/rfi/copag-rfi.php). Within the National Academies, the Astro2020 consultation group, and leadership of the National Academies' Committee on Astronomy and Astrophysics, Space Studies Board, and the Board on Physics and Astronomy discussed the issue and considered the input from the community survey.
On May 24, Space Studies Board Chair Fiona Harrison sent a letter to NASA's Zurbuchen recommending that that the start of the Astro2020 decadal survey not be delayed. Zurbuchen accepted this r ecommendation, tweeting “Upon receiving National Academies analysis with respect to the timing of Astro2020, I directed the NASA team to start the decadal process now. I hope that the US Astrophysics community takes this as an opportunity to come together as one and plan a decade of discovery and exploration - the best yet.” (https://twitter.com/Dr_ThomasZ/status/1000058335570333696)
I have informed my counterparts at National Science Foundation and Department of Energy, NASA's co-sponsors of Astro2020 (http://sites.nationalacademies.org/SSB/CurrentProjects/SSB_185159), that NASA is ready to proceed with initiating the 2020 Decadal Survey on Astronomy and Astrophysics.
Paul Hertz Director, Astrophysics Division NASA Science Mission Directorate
Science Workshop
We are holding a workshop to discuss the PICO science deliverables, the complementarity of PICO data with other data sets that will become available in the next decade, and the key points to deliver to the decadal panel in our report. The workshop will start on the morning of Tuesday May 1 and will last ~2 days. More details will be distributed soon. Everyone is invited to attend. You are particularly encouraged to attend if you wish to shape the message we are providing to the decadal panel. This message will consist of our science goals, areas for future technology development, and NASA's role with CMB science in the next decade.
Instrument Status
After considering the case for a mission that includes both a spectrometer and an imager the EC concluded that the cost cap does not allow for a compelling mission with two instruments. Both instruments would need to be downscoped, sacrificing the overall capabilities compared to a mission with a single instrument. The EC decided to concentrate on a mission with an imager. The decision process included inputs from the spectrometer and imager groups, and from the various science working groups.
The imager's design is quite mature. It currently consists of a 1.4 m aperture, two-reflector telescope feeding a focal plane with 12,400 bolometers. It has 21 bands between 20 and 800 GHz. The current forecast noise is 0.63 uK*arcmin for a 4 year mission (and full sky coverage). More information about the instrument is available in a talk and poster presented during the recent AAS meeting.
Our TeamX engineering and costing session at JPL in mid-December went well. The JPL engineers reviewed the instrument (telescope, focal plane, cooling) and did not identify any challenges with the design. The cost estimate matches the overall envelope.
We will have another TeamX session to assess the instrument in mid-March, followed by an additional session that will assess the spacecraft (power, telemetry, attitude control, mass).
PICO Science
The various science groups have been working on forecasting PICO's performance for its various science goals. This activity will continue over the next 6-10 months as we are preparing the PICO final report.
Brief summary of the science case and some performance forecasts were presented at the most recent American Astronomical Society meeting in the forms of a 10 min talk and a poster. Both are posted on our wiki page. We are also planning to give talks in Moriond and in the April meeting of the American Physical Society.
Foregrounds Workshop
The mission study is sponsoring a 3-day Foregrounds workshop in the University of California San Diego. The dates are Nov. 29 (Wednesday), Nov. 30 (Thursday), and Dec. 1 (Friday), 2017. Please mark your calendars. These dates are a change relative to our previous announcement, but they are more convenient for the vast majority of attendees. For travel purposes, the workshop will begin around 9 am on Wednesday and will end in the early afternoon of Friday. Please register now.
Spectrometer and Imager
The spectrometer group compiled a white paper describing a spectrometer to be added to PICO. The white paper, as well as other material from the group are posted on the wiki. The JPL mission study lead told the Executive Committee (EC) that including a spectrometer will require reduction in the cost of the imager, which translates to a smaller instrument with smaller focal plane. The imager group has developed an imager option with 0.5 m aperture, a factor of 2.8 smaller than the baseline design.
The EC has invited studies from other working groups (Fundamental Physics, Extragalactic Science, Galactic Science) to assess the science trade-offs from a mission consisting of only a 1.4 m aperture imager compared to a 0.5 m aperture imager and a spectrometer. The contributions from these WG are available from the respective coordinators and are posted on the wiki page.
The EC expects a decision by the end of October. You are invited to look at the available documents and provide your thoughts on this issue to any of the EC members.
TeamX Design and Costing
The first detailed design and costing session will be held at JPL in mid-December. This will be an important milestone and will provide a check on our baseline designs. The design of a 1.4 m aperture imager is reasonably mature, as detailed in the imager wiki pages. There are however still opportunities to contribute through the weekly telecons of the imager group. The design of a joint spectrometer and imager mission will require additional development should we decide to pursue this option.
Science Working Groups
The Fundamental Physics, Extragalactic, and Galactic Science groups continue to clarify the science deliverables from PICO. You are invited to participate in their assessment and forecasting work. Please attend the telecons or contact the coordinator.
Conferences, Workshops
- Shaul discussed PICO and its complementarity with CMB-S4 during the August 2017 workshop at Harvard. - PICO will be on display at the AAS meeting in January. There will be a 10 min talk during a 90 min special session dedicated to reviewing all 8 NASA Probe Mission Studies.
Workshops
The mission study is sponsoring a 3-day Foregrounds workshop in the University of California San Diego. The dates are Nov. 29 - Dec. 1, 2017 (Monday - Wednesday). Please mark your calendar. For travel purposes, the workshop will begin around 9 am on Monday and will end in the afternoon of Wednesday. The goal of the workshop is to discuss what we know about the nature of foregrounds for CMB polarization measurements, and about techniques for component separation in all data sets including those obtained from ground, balloons, and space. A web address with full details will be available soon. In the meantime please contact Raphael Flauger (flauger@physics.ucsd.edu) for more details.
We are planning an additional workshop to discuss the science deliverables from the Probe and its complementarity with sub-orbital measurements. The time frame for this workshop is spring 2018.
Data Challenge
The first set of full sky maps at the initial set of frequencies of CMBP are available for analysis as part of the community data challenge organized by the Data Challenge Working Group. The detailed announcement is attached below. Contact Lloyd Knox (lknox@ucdavis.edu) for more details.
Name for the Probe
We are searching for a permanent name for the Probe. Various incarnations of proposed, US-led, CMB polarization missions had these names: Inflation Probe, CMBPol, EPIC (Experimental Probe of Inflationary Cosmology), and PIXIE (Primordial Inflation Explorer Mission). Feel free to opine in favor of one of the past names, or propose a new name; opinions should be sent to hanany@umn.edu.
General
Over the last month the Executive Committee heard reports from all working groups. Several have weekly telecons. Participation in the WG is open to all interested. The WG have their own mailing lists. Please check the main wiki page and contact the lead organizer.
We received additional guidelines from NASA regarding mass, power, and cost margins for the Probe.
Dates for TeamX sessions at JPL to review the design of the Probe and estimate its cost have been set for December 2017 and March 2018.
Data Challenge WG Announcement
Dear CMB Probe Enthusiasts,
We have a few announcements about the CMBP Data Challenge.
1) DC 0.0 is now available at NERSC. See the wiki page here for a description of the sky model and mission model used for DC 0.0, as well as how to access the data. The main purpose of DC 0.0 is to give analysts a chance to exercise their pipelines, and find and fix any simple problems such as incorrect file names, format assumptions, etc. DC 0.0 is quite simple with unlensed CMB and galactic foregrounds. There are no extragalactic foregrounds, no Zodiacal emission, and no gravitational lensing.
2) To begin to prepare the next data challenge, we will start having regular telecons in the beginning of September. Look out for scheduling input request emails sent to the probedatachallenge email list (sign up instructions are in the wiki page linked above in (1).
3) One use of the data challenges is to cross-check map- and fisher-based forecasts, which will be used for the initial optimization of the focal plane frequencies and sensitivities. We are thus looking for participation from those with analytic forecasting tools as well as those who can analyze the simulated data.
—Lloyd Knox On behalf of the Probe Study Team
Thank you to David Chuss and Laura Fissel who have agreed to coordinate a new working group (WG) titled ‘Galactic Science’. This WG will identify and quantify the galactic science deliverables of the Probe. It will be the arena to collect and discuss the input of those interested in the polarization properties of Galactic sources of emission.
Other WGs are beginning to meet. The Systematics WG has a telecon on July 12 and the Imager WG will have its first telecon on July 17. Please check the relevant wiki pages for a current list of WG and coordinators, and for telecon times and connection information. The WGs have their own mailing lists . Please contact the coordinators for more detailed information.
The mission study will sponsor a Foregrounds Workshop in late October 2017. Raphael Flauger is the lead organizer. The purpose of the workshop is to review the state of knowledge of foregrounds for CMB polarization experiments, techniques to identify and separate the foregrounds, and the status of simulations for upcoming experiments including the Probe.
A second workshop tentatively titled ‘CMB Science from a Space Probe and Complementarity with Sub-Orbital Efforts in the 21st Century’ is planned for Spring 2018. More details on both workshops will follow soon.
On May 19 NASA had a telecon for all Probe PIs to provide more information about the studies. Here are some highlights:
We are announcing the formation of three new WG:
The scope of work for these WGs is listed in the main wiki page. Please contact the WG coordinator if you are willing to contribute to the work. The Imager WG has a dedicated wiki page to host its work.
Raphael Flauger reported to the executive committee on the work of the WG in charge of 'Constraints on Fundamental Physics'. The group plans to identify the main science targets for the Probe by mid-July.
We are establishing working groups (WG) to study aspects of the mission. Participation in the working groups is open to all. The first round of working groups is listed below with an initial description of their focus of work. We expect the scope of work to evolve. If you are interested in contributing please write directly to the working group coordinator.