Wow! OK, so 9 detectors and if we assume 90% efficiency (what they typically do), then ~ 300 kg day. That's a lot. That's about 8 times what the commissioning run had.
OK, so what did they see?
Whoa! 4 events in the low energy region (lower blue shaded band). And I was expecting (if you recall) about 15.
4 != Poisson fluctuation from 15. (In case you were about to check.) So was I totally wrong?
Well, wait. It says "several detectors added".
Several != all
I looked up several and google told me it was at least 3. Well, I already knew that 2 had zero (at least part way through). So is this 4 detectors? 8? 5?
Fortunately for me, they claim to rule out inelastic dark matter (and are not the first to do so with CRESST data) by about a factor of 4. Now, I can handle a factor of 4. Data differences, fitting sine functions and of course halo models can buy you those kinds of factors, easy. My general rule is: ruled out by O(1), no biggee. Ruled out by O(10), I am uncomfortable. Ruled out by O(100), I am very uncomfortable. So this is discomfort, but not extreme.
But I can calculate what kind of signal they expect for their parameters. So, delta = 120 keV, m=200 GeV, sigma = 4 x 10^-41 cm^2. What do I get? 17.7 (taking v0=220 km/s, vesc=600 km/s). What is the 90% lower limit on events then (i.e., for how many events would I say 17.7 is the 90% upper limit)? Answer: 12 events.
So I'm thinking that we still have some data to see. Maybe I'm off, maybe that 12 is really 10 or 11, but it's not 4 (which is what I thought when I saw this). 12 is a lot. It's about what you'd expect scaling up the commissioning run. So, if that's the case, I think I'm going to have to wait and see what the data look like...
NW
[Note that if they are using Yellin-type analyses, like maximum gap, then they could set stronger limits with the same number of events, if the distribution if somewhat off from what is expected. So they may have yet more events than this.]
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