SNOLAB Experimental Advisory Committee Barry Barish SNOLAB Workshop May 12-14, 2004

12-May-04SNOLAB Workshop2 A New Opportunity To: The Scientific Community Re: A Request for Letters of Interest in Staging Experiments at SNOLAB Dear Colleagues, SNOLAB, an international facility for underground science, is being developed 2 km underground in INCO's Creighton mine near Sudbury Ontario, Canada. Establishing this facility provides us with new and exciting opportunities in underground science and we look forward to working with you to make SNOLAB a success.

12-May-04SNOLAB Workshop3 A New Opportunity The development of this underground facility and its associated surface facilities is funded by ~$50M from various resources in Canada and in the Province of Ontario. SNOLAB will be developed near the existing SNO experiment with a joint clean area encompassing the full facility. The establishment of SNOLAB will provide opportunities to carry out the best of the next generation of international underground experiments that will benefit from the depth and from laboratory cleanliness conditions similar to those demonstrated in the existing SNO laboratory. The 6000 meter- water-equivalent depth under a flat overburden results in excellent shielding from cosmic radiation and its progenies. SNOLAB will have the lowest muon flux among operating facilities.

12-May-04SNOLAB Workshop4 SNO Laboratory 2000 m rock overburden Almost flat surface Surface support facilities Vertical access Main cavity ~10,000m 3 Solar neutrino oscillation !

12-May-04SNOLAB Workshop5 SNOLAB Concept SNO cavity New Experiment? Ladder Labs -- Machine shop, Low background Rectangular Hall 60x50x50 ft Phase 2 Cryogenic Hall

12-May-04SNOLAB Workshop6 Why New Labs Deep Underground? A clean, quiet and isolated setting is needed to study rare phenomena free from environmental background. Such a setting can be obtained only deep underground, where we can escape the rain of cosmic rays from outer space. –Why do neutrinos have tiny masses and how do they transform into one another? –Are the existence and stability of ordinary matter related to neutrino properties? –Are there additional types of neutrinos? –What is the mysterious dark matter and how much of it is neutrinos? –What role do neutrinos play in the synthesis of the elements in the periodic table? –Is there a deeper simplicity underlying the forces and particles we see?

12-May-04SNOLAB Workshop7 Underground Laboratories Variation of the flux of cosmic-ray muons with overburden.

12-May-04SNOLAB Workshop8 Scientific Motivation Neutrino Properties –Solar Neutrinos –Long Baseline Experiments –Double Beta Decay Dark Matter Proton Decay Neutrinos, Solar Energy, and the Formation of the Elements

12-May-04SNOLAB Workshop9 One Depth Suits All? Cosmic rays create background events that mask the critical events being searched for. –It takes two miles of rock to absorb the most energetic of the muons created by cosmic ray protons striking the earth's atmosphere –At such great depths, the only backgrounds are made by neutrinos (which easily penetrate the whole earth but, by the same token, interact very seldom) and by local radioactivity in the rock itself –Some experiments do not require the greatest depths, while for other experiments there is no option but depth and extreme cleanliness. The SNOLAB facility will provide new opportunities at deep depths and we seek a scientific program to take advantage of that unique feature

12-May-04SNOLAB Workshop10 Underground Laboratories Variation of the flux of cosmic-ray muons with overburden.

12-May-04SNOLAB Workshop11 Kamioka Observatory KamLAND (operated by Tohoku Univ.) Super- Kamiokande 1000 m rock overburden The mine is no more active Support facilities on the surface XMASS R&D Tokyo Dark Matter exp Plot type GW detectors 20m×20m 100m×100m (Cryogenic) 100m To mine entrance (1.8km from SK)

12-May-04SNOLAB Workshop12 Underground Laboratories Variation of the flux of cosmic-ray muons with overburden.

12-May-04SNOLAB Workshop13 INFN Gran Sasso National Laboratory 1400 m rock overburden Flat cross-section Underground area m 2 Support facilities on the surface

12-May-04SNOLAB Workshop14 Gran Sasso Scientific Program Neutrinos from CERN (CNGS) OPERA ICARUS (600ton → 3000ton) (data taken at the surface) Neutrinos from the atmosphere MONOLITH not approved Neutrinos from the Sun GNO BOREXINO LENS proposal Em: 36tons, Pb: 2ktons Observe τ-decay  stop and decay in e Real time measurement of 7 Be ν. It will start soon. Low energy solar neutrino exp with 30ton Ga.

12-May-04SNOLAB Workshop15 Gran Sasso Scientific Program Neutrinos from Supernovae LVD Double beta decay experiments Enriched Ge (Heidelberg-Moscow) Cryogenic techniques (Cuorecino, TeO 2 ) The lab is also used for studies of geology and biology. Search for non baryonic dark matter Several complementary experiments Example: DAMA 100kg NaI detector Nuclear reactions (two accelerators, 40 and 400keV) Fusion reactions in the Sun Anomalous screening in metals (LUNA-2) 1kton liq scintillator detector

12-May-04SNOLAB Workshop16 Underground Laboratories Variation of the flux of cosmic-ray muons with overburden. Proposed Multipurpose Underground Laboratory in the U.S.

12-May-04SNOLAB Workshop17 Proposed U.S. Underground Laboratory -- Present Context Compelling case has been established for the broad range of science (physics, astrophysics, biology, geology and national security) at a deep underground laboratory. The case validated by a number of studies, including –two National Research Council (NRC) reports –a soon-to-be-released National Science and Technology Council report prepared by the Interagency Working Group on the Physics of the Universe. Proposals for Homestake mine, San Jacinto and Soudan NSF carried out a site review process and selected Homestake as the most promising site. Since that review, however, the pumps have been turned off at Homestake, and the mine is now flooding. Moreover, additional sites have been put forth.

12-May-04SNOLAB Workshop18 Proposed U.S. Underground Laboratory -- Process at NSF The Directorate for Mathematical and Physical Sciences (MPS) has moved to put in place a deliberate process that has NSF working with the community to develop a course of action that will realize the scientific opportunities before us. In broad outline, NSF process consists of returned the submitted site proposals without prejudice informational meeting held at NSF to describe roadmap and to receive community feedback - 29 March 2004; work with the Department of Energy (DOE) to develop mechanisms for selecting and jointly funding underground science experiments issue a series of up to three solicitations for planning grants beginning this spring. Underground science community is joining toward making one joint proposal to NSF for an underground laboratory

12-May-04SNOLAB Workshop19 Proposed U.S. Underground Laboratory -- Process at NSF Concerning the solicitations –the purpose of the first is to provide funds to one or more groups to develop detailed science modules reflecting the range of science opportunities noted above and to specify the associated infrastructure requirements. –The second solicitation, issued at the same time, would fund several site development studies. –The final solicitation, a year or more into the future, would provide funds to develop underground laboratory proposals combining site infrastructure with a suite of initial science experiments for NSF consideration. The third solicitation would only occur if MPS and its partners determined that timely construction of a major new facility is needed to realize the scientific opportunities..

12-May-04SNOLAB Workshop20 Underground Laboratories Variation of the flux of cosmic-ray muons with overburden.

12-May-04SNOLAB Workshop21 Experimental Advisory Committee The SNOLAB Experiment Advisory Committee (EAC) is an expert and advisory panel to review Letters-of-Interest from the scientific community and, eventually, proposals for projects at SNOLAB and provide advice to the SNOLAB Director on priorities for siting experiments in the laboratory. The objectives of the EAC are: a) develop an experimental program of the highest scientific merit, b) study in detail the technical feasibility of individual projects, c) prioritize projects for siting in SNOLAB, taking into account time lines for the projects as well as scientific merit, and d) consider proposals for allocation of development space for programs that require such space for research and development. Members of the EAC should be representative of the Canadian and international community active on underground science and have good knowledge of the scientific areas under consideration.

12-May-04SNOLAB Workshop22 Barry Barish... Chair... Caltech Baha Balantekin... Univ Wisconsin, Madison Cliff Burgess... McGill Takaaki Kajita... ICRR Tokyo John Martin... Toronto Ken Ragan... McGill Kate Scholberg... MIT Dave Wark... Imperial College Andrew Hime …. ex-officio (Associate Director for Scientific Development and Chair of the Scientific Executive Committee (SEC)). SNOLAB EAC Membership

12-May-04SNOLAB Workshop23 Letters of Intent Experiment: COBRA Contact: Kai Zuber Scope: Double Beta Decay Workshop Presentation: Yes LOI: Received Experiment: Majorana Contact: Steve Elliott Scope: Double Beta Decay Workshop Presentation: Yes LOI: Received Experiment: GERDA Contact: Iris Abt Scope: Double Beta Decay Workshop Presentation: Yes LOI: Expected Experiment: EXO Contact: Giorgio Gratta Scope: Double Beta Decay Workshop Presentation: Yes LOI: Expected Experiment: SNO with Scintillator Contact: Mark Chen Scope: Solar Neutrinos and Double Beta Decay Workshop Presentation: Yes... with McDonald & Caccianiga LOI: Received

12-May-04SNOLAB Workshop24 Letters of Intent Experiment: Lithium Detector Contact: Anatoly Kopylov Scope: Solar Neutrinos Workshop Presentation: No LOI: Received Experiment: Noble Liquid Tracking Detector Contact: Bill Willis Scope: Solar Neutrinos Workshop Presentation: Yes LOI: Received Experiment: CLEAN Contact: Dan McKinsey Scope: Solar Neutrinos and Dark Matter Workshop Presentation: Yes LOI: Expected Experiment: CDMS Contact: Dan Akerib Scope: Dark Matter Workshop Presentation: Yes LOI: Note from Dan Akerib Experiment: ZEPLIN Contact: Nigel Smith Scope: Dark Matter Workshop Presentation: Yes LOI: Expected

12-May-04SNOLAB Workshop25 Letters of Intent Experiment: PICASSO Contact: Viktor Zacek Scope: Dark Matter Workshop Presentation: Yes LOI: Expected Experiment: DRIFT Contact: Jeff Martoff Scope: Dark Matter Workshop Presentation: Yes LOI: No Experiment: DRIFT-III Contact: Neil Spooner Scope: Dark Matter Workshop Presentation: No LOI: Received Experiment: XENON Contact: Tom Shutt Scope: Dark Matter Workshop Presentation: Yes LOI: Received Experiment: HALO Contact: Charles Duba Scope: Supernova Neutrinos Workshop Presentation: Yes LOI: No

12-May-04SNOLAB Workshop26 Goals: Dirac or Majorana particle? Ettore Majorana Majorana : The neutrino is its own antiparticle

12-May-04SNOLAB Workshop27 Solar Neutrinos – The Future In the standard solar model the flux from the pp reaction is predicted to an accuracy of 1%. Further, the total flux is related directly to the measured solar optical luminosity. Such a copious and well-understood source of neutrinos is ideal for precisely determining the neutrino masses and mixings. It also affords a way to search for hypothesized sterile neutrinos as much as a million times lighter than those explored by present experiments, provided they mixed sufficiently with the active neutrinos. Unfortunately, the pp neutrinos have very low energies

12-May-04SNOLAB Workshop28 Dark Matter – Direct Searches

12-May-04SNOLAB Workshop29 EAC Goal Work with SNOLAB and the community to develop the most promising program for the new laboratory taking into account: –Science potential is the highest priority! –The approved program must have significant discovery potential and strong collaborations to obtain funding –The experiments should take advantage of the uniqueness of great depth at SNOLAB –The program should be determined in the context of other plans worldwide. –R&D toward proposals not yet mature should be accommodated where possible. EAC will provide strategic and technical guidance, in order to construct a deep underground laboratory expeditiously and in synergy with a world class research program.