Spectroscopic Follow-up: Average follow-up time for a volume-limited sample is about 3/7 = 0.43 of the time to do the faintest object. If N(z) flattens, this factor might be even better, about 0.3 Here I calculate the follow-up for Bmax = Vmax = 18.8, corresponding to z = 0.1 needed to get S/N = 10 per 3A pixel. For K-corrections this is overkill. S/N = 10 per 50A should be sufficient, which requires 16.6x less exposure; this would still give S/N ~ 45 per 1000A filter. ** Exposure Schedule for s=1 SNe ar z = 0.1 *** Day m(B) Exptime Exptime Exptime 4-m 4-m 2.5-m (min) (min) (min) S/N=10 3A S/N=10 50A S/N=10 3A ------------------------------------------------ disc 19.8 25 ---- 60 -10 19.1 6 ---- 15 0 18.8 4 ---- 10 10 19.7 20 ---- 50 20 20.9 175* ---- 450* 30 21.4 440* 25 --- 40 21.8 900* 54 --- 50 22.0 1325* 80 --- 60 22.3 2300* 140* --- (* exposure times over 2 hr cap) So this says we need 3/7*8.8 hrs of 4-m time per SN, which is 3/7*33 = 14 (8-hr) nights on a 4-m. I would just set all exposures past day 15 to 2 hrs for z = 0.1. This gives 3/7 * 11 hrs of 4-m time per SNe, or 18 nights of 4-m time for 30 SNe. This cap means that S/N per 3A would be about 2.5 at day 60; still good enough for K-corrections I think. Using 2.5-m telescopes only saves about 3/7*1 hr of 4-m time per SNe, or about 2 nights. So, we want ~16 nights of 4-m time and 4 nights of 2.5-m telescope. We also need discovery screening time, which the 2.5-m telescopes can be used for (S/N doesn't have to be nearly as good for screening). Note that if the 2 hr cap is applied to all SNe, regardless of brightness, then more time is needed and the calculation is more complicated. For example at z = 0.05, exposures on a 4-m are 2 hrs or less out to about day 50. Once we have a prediction of the redshift distribution, a better estimate can be made (although there will still be a range of 1 mag in peak brightness at a given redshift - really need the distribution of peak magnitudes, which Peter is generating).