Double Beta Decay/Low-Level Counting

Questionaire

The NESS02 organizers would like experimentalists presenting proposed experiments to provide information that can be passed on to the NRC committee. While we realize that a great deal of information has been compiled over the last year, your responses will still be helpful to the committee, coming directly from the proposers. The questions are also a guide to issues you may want to address in your talk:

1) Please describe the proposed schedule of the experiment, including any staging that is contemplated. Estimate the end goal in terms of kg-years of counting.

2) Identify the issues that you regard as remaining R&D challenges. Indicate what steps are being taken to address these challenges.

3) Give the expected energy resolution of the detector and the implications for interference from the two-neutrino mode.

4) What do you regard as the limiting experimental feature of the proposal?

5) Describe the natural radioactivity issues, with particular attention to radon. What requirements exist for coating the walls of the underground cavity, for ventilation, for gas scrubbing, and for maintaining radon-free volumes?

6) What are the floor-space requirements? Are you aware of any safety issues that might affect siting, such as cryogenics?

7) Describe the expected depth requirements and the basis for this estimate. What are the countermeasures employed (active or passive shields, vetoing backgrounds correlated with penetrating muons, deadtime issues, etc.)? Address punch-through neutrons produced outside the shield and both charged (e.g., (n,p)) and neutral (e.g., (n,3n)) reactions that they induce, producing gammas or betas.

8) What is the estimate cost? Please separate special materials costs, such as large quantities of enriched isotopes, from other costs.

9) Please list facilities that, in a multipurpose laboratory, might be used or shared. Examples include underground storage for materials, low-level counting facilities, special facilities for handling cryogens, underground facilities for growing crystals, etc.

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10) Most of these questions are not relevant for the Friday (low-level counting) session. However, speakers are invited to describe the cost and sensitivity of facilities under consideration.

Giorgio and Wick