Friday, December 18, 2009

No dark matter, yet...

So, what happened with all this CDMS fuzz? The collaboration reports 3 events out of a expected background of 0.5. Nonetheless, one of the events was out of the "box", so lets forget about it. So, with 2 events we have a 1.06 sigma signal and with 3 events we have a 1.7 sigma signal.

It is just a ridiculously low signal, and by no means can be considered a discover. Nonetheless, it is rather interesting and intriguing. Experiments using liquid targets have a significantly bigger mass and can catch up this signal in one, maybe two years to a level where it can actually be considered a detection, but, until then, the coin is still in the air regarding dark matter.

3 comments:

Michael Schmitt said...

Hi Luis,

you're right, it is a very low signal, but the main problem is that it is not much larger than the expected background. Recording two events when you predict 0.8 on average is not exciting. But your predicted 0.08 events, then recording two would be great!

Let's see what Xenon observes...

regards,
Michael

Luis Sanchez said...

Indeed, I agree. I should be more explicit about that on the post.

By the way, what is the usual criteria for events where are just not expected, but of which you only have a marginal signal? (I am thinking about the eegmet, for example).

Cheers,
Luis

Anonymous said...

Choice at you uneasy