Preliminary Input Catalog

For the purposes of testing tiling and survey strategy, the following columns will be given (by Simon) in the input catalog.
  • Co-ordinates: UCAC4. (note that occasional 2MASS sources may be missed, but we're OK with that. To be over-written with Gaia co-ordinates?)
  • UCAC4 identifier (our master)
  • Epoch.
  • Proper Motion.
  • J,H,K (2MASS), uncertainties and flag from UCAC4
  • B_T, V_T and uncertainties. [cross-matching needed, but the Tycho number is given in UCAC4]
  • ALLWISE (not needed in first instance)
  • APASS (not needed in first instance)
  • Skymapper photometry (not needed in first instance)
  • Priority (note that when joining sub-catalogs, the highest priority should be entered here. Currently 0 for random stars and 1 for M dwarfs).
  • I_F (FunneWeb I magnitude), uncertainty and source of I_F. From (in this order):

  1. Skymapper.
  2. APASS
  3. I(B_T,V_T) if sigma(B_T,V_T)<0.02
  4. I(J,K)

The catalog is a union of the following selection criteria:
  1. delta < +20, I_F < 10
  2. delta < +20, |b| > 10, I_F < 12
  3. Priority 1 likely M dwarfs, selected for now by J-H<0.7, H-K>0.2, sigma_J,H,K<0.03, I_F<14, delta < +20.

Thoughts on Tiling

(from 4 Nov email)
Try high priority tiling restricted to one magnitude range.
- In the I=5-8 range, assign I=5-7 higher priority, and tile using greedy until those high priority stars are “done".
- In the I=7-10 range, assign I=8-9 higher priority, and tile using greedy until those high priority stars are "done.
- In the I=9-12 range, assign I=10-11 higher priority and tile using greedy until those high priority stars are “done".
- In the I=11-14 range, tile using greedy until all those high priority stars are “done".

As long as the full range of priorities is used for each magnitude range tiling, it is likely that this scheme will be optimal for a combined weighted method with roughly equal weighting.

(7 Nov email)

Make a “generate_tiling_funnelweb” routine in, which starts as a copy of “generate_tiling_greedy”, but instead has candidate targets as a list of lists and a slightly different algorithm. Given that the tiling of each magnitude range is linked with overlap, I don’t think it is optimal to just tile one magnitude range at a time.

Note that in "" there are a number of fixed parameters that do not apply to FunnelWeb:











In particular, the list of guides need not have the same magnitude range as TAIPAN, and few or possibly no Standards are needed. Standards are simply blue stars in the same magnitude range as the rest of the field.