LBNL-2016: Time-Ordered Data Processing
Time-Ordered Data Processing Birds-of-a-Feather Session: Wednesday, March 9, 9 AM
Attending: Julian Borrill, Tom Crawford, Ted Kisner, Kris Gorski, Graca Rocha, Clem Pryke, Nick Harrington, Jesse Treu, Kyle Story, Nathan Whitehorn, Olivier Perdereau, Reijo Keskitalo
Discussion of TOD scanning simulations
- Scanning with full 4-pi beam: do we really get the 4-pi beam at high fidelity?
- at some level, not the data folks' problem.
- Are we really going to simulate full TODs, including data that we will eventually cut in the real TOD?
- yes, at least to test automated data cuts.
- who is going to take on the task of creating this model?
- we pretty much know how to do it now, unless the fundamental detector and/or readout architecture changes.
- Do we need to simulate TES & electronics response?
- Not a high priority. Assume detectors/electronics with funky response will not pass CD.
- RFI pickup?
- Impossible to implement in sims without model of pickup.
- Time-dependent focal plane / optics distortion?
- Real-world examples to go on from ACT & PB
- We need scan strategy to be defined to do sims.
- Is anyone considering using anything but azimuth scans as fast and wide as you can go?
Digression into computing plan
- Are we really going to use grid computing (rather than parallel processing on large clusters)?
- Certainly not for anything for which we have to send around real TOD. (I.e., just for sims.)
- What about data management / delivery from sites?
- Pole bandwidth barely accommodates SPT-3G and will be unlikely to increase enough to handle S4. Similar issues exist in Atacama.
Return to TOD sims
- Will there be half-wave plates on S4?
- Can't rule it out. How do you make a model of non-ideality for a HWP?
- Are we aiming to have a perfect set of TOD sims by summer or 10 years from now?
- There will be a profile of what we can simulate. Could in theory have some level of TOD sims by summer.
- What about atmosphere?
- Moving slab prototypes exist.