SV 20250729

As of 20250729, the SV survey has acquired a total of 12184 visits, of variable quality. The median numbers of visits per pointing within the primary wide SV survey area are:

	u	g	r	i	z	y	all
(20250729, ‘Nvisits’)	2	3	7	7	7	5	34

A simulation database containing acquired visits up to 20250729 and extended to the end of the SV survey: sv_20250729.db. Note that these databases contain preliminary visit metadata; not all visits will successfully pass through processing into data releases, and metadata may change with further processing or information. The system is still under commissioning.

The SV survey has now acquired approximately 25% of its expected visits.

The current and predicted number of visits over time is shown above. However we can also look at how the prediction for the total number of visits at the end of survey has changed with each incremental simulation. Looking at the predictions for the end of survey in this way, we can see that early predictions for the total number of visits were quite high; more recent predictions have fallen in comparison. Remember that the current survey simulations include updated assumptions about the observatory; the reference simulation, sv_sim_1.0.db, was created based on assumptions about performance coming from best estimates and experience from DP1. The newer simulations have updated slew times, downtime assumptions, etc. Thus early simulations estimated more visits total than the reference simulation; recent bad weather has affected the rate of visit acquisition and so now the predicted number of visits at the end of the SV survey has fallen accordingly. The weather has been particularly unlucky recently, with the dome entirely closed for five nights within the last week and for parts of three nights in the preceding weeks.

Likewise, we can look at the current prediction for coadded depth over the primary SV survey area and how this has changed over time.

Last Updated

Last Updated 2025/07/30