Minutes from the November 19 meeting

Attendees (in no particular order): Bob Bernstein, Peter Shanahan, Ray Stefanski, Boris Kayser, Andrea Romanino, Mario Campanelli, Bruce Brown, Craig Moore, Mike Shaevitz, Mayda Velasco, Fritz DeJongh, Debbie Harris

Superbeam Studies Update: Fritz DeJongh

Specifically--Fritz and Debbie have been looking at possible beamline designs for a beam to Homestake, and Dave Casper has been in contact with Fritz, to use his fast monte carlo to figure out how water cerenkov would work at these energies. (i.e. 1.5-2.5GeV).

Fritz showed a comparison between a narrow band beam created with a dipole compared to one coming from an off-axis beam, with the same peak energy. The dipole beam had about 40% less flux in the peak bins, but the cutoff at high energy was sharper, which would mean a lower neutral current background level.

Fritz also followed up on a discussion at an earlier meeting on the possible aperture sizes for a dipole--according to the JHF to SuperK proposal, they assume a dipole with a 60cm diameter, which is also the diameter of the first NUMI horn. So large diameters are feasible. This was also confirmed by Nikolai Molkhov.

Future Plans

there will be an NNN workshop in Louisiana with more FNAL participation, in hopes of getting us and them better acquainted and in hopes of our getting our hands on the detector simulation tools! Also, BIG NEWS: starting in December Nikolai Molkhov and Mikail Kostin will be working on beam design issues associated with sending a beam from Fermilab to Homestake--Mikail has been working on MINOS as a post-doc from the University of Texas at Austin, but will be starting his new job with Nikolai Molkhov in December.

There was a question raised about what the goal of a superbeam program should be: should we only say we're trying to see CP violation? This leaves us open to the problem of if the solar solution isn't LMA then it implies that there's no point in the entire program. Bob Bernstein raised the question shouldn't we be trying for theta_13 and matter effects first?

Neutrino Community Consensus: Mike Shaevitz

Mike Shaevitz commented that we need to form a consensus on the next neutrino experiment: i.e., what the best energy, the best detector, (the best baseline?) Once we get a consensus on what the next experiment looks like then it would be easier to get more of the community to back it, and it will be easier to get the proton driver upgrade pushed ahead.

By "next neutrino experiment" Mike meant what comes after MiniBooNE, MINOS, and any possible NUMI off-axis experiments. Mayda suggests that we need to wait until KAMLAND says something concrete about the solar neutrino anomaly (LMA or not LMA?) then we can figure out what the motivation is for a superbeam to Homestake. The the presence of a concrete motivation will inspire more of the community to support such a big initiative.


We need a realistic study for a design for a proton driver, even if it's put on the shelf for awhile. Coupled with that is the need for a report on the physics potential of the superbeam fed by that driver. Maybe this report needs two scenarios in it: what if the solar solution is LMA, what if it isn't? How does that change what we should be trying to measure?

Then if a LC doesn't come to Fermilab then we have these two studies that we can pick up and stat putting real resources into. We don't want to have to wait for a LC decision to START doing these studies!

Mayda points out that given the funding (and by implication physics) delay at CERN and the LHC, the proton driver at Fermilab should be pushed ahead since it becomes more relevant for Run II. She heard that the funding level at CERN will stay constant over the next few years, they aren't getting the increase they asked for.

Moving on to the HEPAP Subpanel Report:

First of all, there's a new mailing list that Bob Bernstein set up to discuss what we as a neutrino community should propse as an edit to the report --there have already been some interesting comments on the report, and if you subscribe (send mail to listserv@fnal.gov with one line of text in the body of the message reading "subscribe nupap firstname lastname" leaving the subject line blank) Bob B. will forward those emails to you so you don't miss anything juicy.

There was a brief discussion of an email Cat James sent to the mailing list, she warned about making the same mistakes with a LC that were made with the SSC: she's afraid the report lowball's the cost and the schedule of an LC.

The general concern with the document is that if the LC slips or goes over budget then the field will really be in trouble. Also, the statment is that if the LC is onshore, there is a 10-12 yewar gap in funding for new initiatives.

Some things that it was agreed we should ask the hepap subpanel writers to stress more were:

Also, Mayda requested that we actually suggest something along the lines of "if the linear collider is onshore but not at Fermilab then the proton driver and superbeam should be pursued Fermilab" but the rest of the attendees were worried that adding too many requests to the report would dilute the message. Debbie H. also expressed concern that the field wasn't going to necessarily support two large underground water detectors. (but others assured me I was being pessimistic).

But in general it was agreed that we should ask for some text that preceeded the two scenarios saying that while there is an obvious ordering that was chosen for the scenarios, we should be prepared for the possibility of either one. i.e., not put the rest of the program on hold while the LC location decision is being made.

Bob B volunteered himself and Debbie to try and write a concise suggestion incorporating the above ideas and pass it around to the nupap mailing list.
Deborah Harris
Last modified: Mon Nov 19 16:17:38 CST 2001