Tianlai Analysis Teleconference

Peter Timbie, Peter Timbie (UW-Madison)


  • 21 cm Cosmology Workshop -  we now have 30 people registered and more than 13 keynote speakers.  Website is here:   https://tianlai.bao.ac.cn/meeting/2024/
  • Observation status:
    • Jixia - Dish correlator board seems to need a chip replacement.  It has been replaced temporarily with the cylinder correlator board and the dish array is now seeing sky signals again.  The fiber optic cable to the CNS was damaged during construction so a new cable has been run above ground.  This cable was damaged by sheep but has been repaired.
    • Xuelei - Fengquan is installing a ground plane at a site between the two outrigger sites.  Consists of rolls of conducting net, about 60 m across, with an Aluminum plate at the center.   A 'star' shape has been added similar to EDGES for reducing sidelobes.
  • Notes from the Cosmology in the Alps conference in March.  https://indico.skatelescope.org/event/1098/
    • Xuelei:  
      • Datta group reported computing power spectra directly from visibilities using GMRT data.   They are interested in trying the same with Tianlai data - may have a student available to try this.
      • Seth Siegel has used holography for measuring CHIME beams with bright point sources.  Xuelei asks whether could work on blank sky.  Not clear!
      • Discussed with Alex Refregier and Jon Sievers possibility of designing a dedicated satellite to calibrate ground-based radio arrays (HERA, Tianlai, etc.)   Need to know the beam shape of the emitter.  
    • Reza may report at future meeting
  • WIYN/Hydra NCP Survey paper
    • Meeting still planned for May 22-24 in Madison, remote participation will be possible
    • Need to meet soon (this week) to clarify plans.   Meeting friday this week is problematic.  Peter will ask Albert to set up a new time.
    • Rooms have been set aside and can be reserved until April 29:  Graduate Hotels
  • Next call in 2 weeks.
There are minutes attached to this event. Show them.
    • 8:00 AM 8:01 AM
      Minutes for last meeting (March 25) are posted 1m
    • 8:05 AM 8:15 AM
      Update on planning for Tianlai Collaboration meeting/ 21 cm Cosmology Workshop in Hangzhou 2024 10m
      Speakers: Albert Stebbins (Fermilab), Haijun Tian, Peter Timbie (UW-Madison), Reza Ansari (Univ. Paris Sud & LAL, CNRS/IN2P3), Xuelei Chen (NAOC)
    • 8:20 AM 8:25 AM
      Update on Tianlai observations, including repeated TDA drift scans of calibration sources 5m
      Speaker: Jixia Li (NAOC)
    • 8:35 AM 8:40 AM
      Update on WIYN NCP spectroscopic survey paper 5m
      Speaker: Albert Stebbins (Fermilab)
    • 8:40 AM 9:00 AM
      Highlights from Cosmology in the Alps conference 20m
      Speakers: Reza Ansari (Univ. Paris Sud & LAL, CNRS/IN2P3), Xuelei Chen (NAOC)