# Presentation: 033289

## Executive Summary

- R.N. Cahn, W.C. Carithers, S.J. Freedman,
- K.M. Heeger, R.W. Kadel, V. Koch, K.T. Lesko,
- Z. Ligeti (deputy), K-B. Luk, H. Murayama,
- E.B. Norman, D.R. Nygren,  A.M. Sessler,
- R.G. Stokstad (chair), J.S. Wurtele, and M.S. Zisman

- Neutrino Science at LBNL
- Present Program and Future Options

- Neutrino Working Group

## Charge

- The working group should survey the theoretical landscape and recent experimental results to provide a framework for understanding which will be the most compelling next set of neutrino experiments world-wide. All ongoing and planned neutrino-related work at LBNL should be surveyed and placed into the above context by the working group through discussion with the proponents. The resulting theoretical context, the ongoing program, and future options should be presented at a joint one-day retreat and workshop in early December open to members of all three divisions. The future plan should lay the groundwork for development of proposals (both LDRD and external) for support of our work.

## Science

- Recent Discoveries

- Open Questions

- Majorana or Dirac ?       Absolute Mass Scale ?
- Mass hierarchy ?           13 = ?
- CP violation ?                H.E. 's from the Cosmos ?

## Present Program

- Neutrino properties

- SNO			        Solar 's     	   12 , m212
- KamLAND		        Reactor 's 	     12 , m212
- Cuoricino		         decay	    m, Maj or Dir
- Neutrino Factory R&D     Accelerator 's     CP-viol.)

- R&D for next generation solar  detector

## Opportunities

- Must invest in the future.
- Exciting opportunities abound.
- Future will be mix of present and new experiments.
- Must make wise choices - science & suitability for LBNL.

## Resources and Strategy

- Resources to pursue an opportunity are modest.
- Resources to implement a funded proposal can be significant.
- Success in pursuing an opportunity is not guaranteed *a priori*.
-               pursue several opportunities
- Strategy: have a balance of funded experiments in progress and options being pursued.
- Selecting options to pursue requires setting priorities

## Criteria

- Is the science outstanding?
- 	Fundamental, timely, important consequences, ...
- Is it appropriate for LBNL?
- 	We must make a unique and important contribution.
- Is there local interest and expertise?
- 	Who wants to do it?
- Is it within the realm of possibility?
- 	Prospects for funding, interdivisional/UCB collaboration, resources, national need (long range plans), etc.

## Priorities

- The first requirement in addressing the future is to meet the commitments implicit in the present program.
- Success in meeting present commitments provides the basis on which we
- build the future --- a future that will contain elements of the present program
- and new initiatives.

- Priority for opportunities:
- 1. Neutrinoless double beta decay
- 2. A reactor measurement of 13
- 3. Measurements of 12 and tests of the Standard Solar Model
- 4. Development of scientific and tech. infrastructure for NUSEL

## Double Beta Decay

- Opportunities

- The next generation of 0 detectors will have the sensitivity to detect effective masses of ~ 10's of meV -- in the mass range suggested by oscillation experiments.

- CUORE (Cryogenic Underground Observatory for Rare Events)
- 760kg of 130Te   TeO2 crystals at 10omK     ~$10M   proposal in preparation
- 40kg (Cuoricino) has begun taking data

- Majorana   500kg  76Ge cooled crystals, enriched isotope, ~$100M
- LBNL Ge detector technology (GRETA, -ray tracking) ideal for Majorana

## Reactor  meas. of 13 

- Opportunities

- Two detectors appropriately positioned between 2 and 10 km.
- Secondary oscillations determine 13.

## Opportunities

- Increase precision on fundamental matrix element.
- Definitive tests of Standard Solar Model.

- KamLAND-II --  reduce backgrounds to enable detection of 7Be solar neutrinos.
- Next Generation Solar Neutrino detector -- detection of pp solar neutrinos.
- LBNL involved in R&D on HERON.

## NUSEL

- The longstanding goal of a national underground laboratory may be achieved in the near future in a facility that would be funded by the NSF.
- LBNL will likely be involved in experiments to be sited there.
- LBNL could further the cause of NUSEL by participating in the development of the scientific and technical infrastruture of the underground laboratory.

- Opportunities

## History

- We have made good choices in the past:
- 1989 - Sudbury Neutrino Observatory
- 1990 - NTD Thermistors for Cuoricino (NSD joined in 1998)
- 1995 - Neutrino Factory R&D
- 1997 - AMANDA/IceCube
- 1999 - KamLAND

## FUTURE

- We have excellent opportunities to pursue now

## Slide 15

## Neutrino Science Effort

- IceCube		14
- KamLAND		  9
- SNO			  5
-  Factory		  3
- Cuoricino		 1.5
- Solar  R&D		 1.5

- Scientists		14
- PostDocs		  6
- GSRA			  3
- Engineers		10

- Presently ~34 FTE