Minutes from the July 29 Meeting
Current version of Detector R&D document, which
now includes the theoretical motivation section, thanks to Robert Shrock,
Gabriela Barenboim, and Andre deGouvea, a very slim intro by yours truly,
and a targeting section thanks to Mikhail Kostin.
We talked about the document for awhile, and discussed the PAC's
response to the numi off-axis documents (both the proton driver upgrade
and the LOI). We talked about the "8 questions" that the PAC commented
on, and which of those we would address in our R&D document.
The list is: (paraphrasing)
After looking more at the outline, it was suggested that we have another
section in the "other r&d needs" chapter on proton intensity upgrades,
and Doug Michael has kindly agreed to write this. Also, it was suggested
that Bob Svoboda be asked to write up a section on liquid scintillator
detectors--he's been talking about the possibility of expanding to a
100kton detector which might have similar performance to a liquid argon
detector (I haven't personally seen any monte carlo plots to show this...
but anyway it's much more light than water cerenkov). Anyway, as of
the typing of these minutes I haven't heard back from Bob yet.
- Can you pick an off=axis location today?
(in other words, how much would
lose if you picked a spot today and delta m2 ended up at 1.5,2,3,3.5eV^2?)
Probably we won't address this in a substantial way in the R&D document.
- What is the optimal detector technology per fixed cost?
It's possible that the optimal detector technology depends a little on
what you're trying to do: if you're trying to get the lowest theta13,
that's one thing, if theta13 is large and you're just trying to get the
statistics, then the NC background doesn't matter quite as much...and it's
back to just a question of what detector has the largest mass*acceptance
per unit dollar? This question will definitely be discussed in the
- What is the discovery reach and achievable precision on theta13?
again, probably detailed analyses are outside the scope of this document.
we can certainly give the "rough estimates" we have now...and refernece
the more detailed studies that have happened thus far.
- What supporting measurements are critical to understand the background?
this is partly going to be discussed in the "near detector cross section
measurements" section written by Kevin. Also one could put a plug or a mention
of MIPP here
- if the MINOS on axis near detector is the only one available to
characterize the beam, how well can the flux be known?
we can address this somewhat by talking about how it's the backgrounds
that are important more than the fluxes, and that the NC backgroudns
especially have to be measured in the same type of detector...not the
MINOS on axis near detector.
- How well does detector proposed fit into a longer term program to
measure CP violation? Shoujld one adopt in the first stage the technology
most appropriate for later stages?
this is definitely something our report will address (in the
- How significant are the cosmic ray backgrounds? Can the detector
be on the surface?
again, this is in the second chapter: on-surface vs below ground...
- Are there other important measurements that a 20kton detector optimized
for electron ID could perform?
since it's imagined that this detector would be on the surface,
then it's unlikely it would be good for other (i.e. solar, atmospheric)
physics...but in the "expandability" section it would be worth noting
that if you are going to go through the trouble of making an extremely
large very sensitive detector, then there the additional cost of putting
it somewhere below ground might actually be worthwhile for the other physics
(proton decay, etc.). Mark Messier pointed out that if we're going to talk
somewhere in this report about non-accelerator measurements, then we should
also mention somewhere that there's plenty of non-oscillation neutrino
physics to do at the near detector...(i.e. mention this early in the intro,
Last modified: Fri Aug 9 16:44:48 CDT 2002