Parallel Session: 21 cm

US/Pacific
50A-5132

50A-5132

Description

Meeting Webpage
Timetables
Remote: https://lbnl.zoom.us/join Or by phone,   US: +1 646 558 8656  or +1 669 900 6833  or +1 855 880 1246 (Toll Free) or +1 877 853 5257 (Toll Free).   
NEW Zoom link https://lbnl.zoom.us/j/144355963 Meeting ID: 144 355 963

 

  • Tuesday, 14 November
    • 12:45 14:45
      Parallel Session: 21 cm

      TUESDAY SESSION

      This session will be devoted to generation of science goals for an ambitious experiment to follow LSST/DESI.

      We will start with updates from current state of the art, talks are 10+5

      Tzu-Ching Chang: 21cm from GBT
      Richard Shaw: CHIME
      Kavilan Moodley: HIRAX
      Albert Stebbins: Tianlai

      followed by discussion (1 hour) on main science goals:

      • expansion history to z=6
      • Neff and mnu constraints (or helping other probes improve them)
      • tidal mapping and weak lensing
      • non-Gaussianity
      • PZ calibration

      What are the unique strengths of 21-cm vs galaxy surveys beyond its cost?
      What are its main weaknesses? How do we go around them?
      What are opportunities and threats to the program?

  • Wednesday, 15 November
    • 11:00 13:00
      Parallel Session: 21 cm

      WEDNESDAY SESSION

      This session will be devoted to the white-paper entry in 21cm. The main possibilities we have discussed are:

      • Join HIRAX/TIANLAI
      • Make are HIRAX clone
      • Build an instrument for GBT:
        • short backfire antenna pixel based camera based of Tzu-Ching's work. Perhaps a 7 element at 700-900MHz and 4 element at 400-600MHz.
        • phased array working 350-1.2GHz, optimized at 400-600.

      The nominal science goal is PZ calibration of LSST photo-z's beyond beyond reach of DESI. The cost has to be low O(10)million. The main difficulty is kparallel space overlap.

      For all cases we need to answer:

      • How will this effort enhance our current knowledge of dark energy?
      • How does the idea complement other efforts?
      • Cost estimate
      • Timeline
      • What are the key technical and logistical obstacles (if any)? (Examples: data sharing among collaborations, existence of an instrument, international engagements, etc)

      In addition, how can we be sure that we'll have sufficient number of common modes? What is the back-up science case?