Name: Parallel Session: 21 cm
Start: 2017-11-14T08:30:00-08:00
End: 2017-11-15T17:00:00-08:00
Location: No location set

Tuesday, 14 November
- Mon, 13 Nov
- Tue, 14 Nov
- 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
- Mon, 13 Nov
- Tue, 14 Nov
- 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?

Parallel Session: 21 cm

50A-5132

TUESDAY SESSION

WEDNESDAY SESSION