Neutrinos & Fundamental Symmetries

Daya Bay detector

Current Projects

Argon Neutrino Test (ArgoNeuT)

Links:  Fermilab websiteYale websiteBonnie Fleming

Diagram of ArgoNeuT courtesy of B. Fleming Group.ArgoNeuT, an R&D experiment designed to detect and record neutrino interactions from the Neutrinos at the Main Injector (NuMI) beam at Fermi National Accelerator Laboratory (Fermilab), was the first Liquid Argon Time Projection Chamber (LArTPC) operating in a low energy neutrino and antineutrino beam, the region of interest for current short-baseline and future long-baseline experiments.  In addition to demonstrating technology for larger detectors and contributing to the development of reconstruction algorithms that will be useful in future experiments, ArgoNeuT has provided a wealth of physics results on neutrino interaction mechanisms, and is still yielding new intriguing outputs from the on-going studies.  The Yale team played a leading role in the project and the group is currently analyzing and using the data for several research programs.

Cryogenic Underground Observatory for Rare Events (CUORE)

Links:  INFN websiteYale websiteKarsten HeegerReina Maruyama

// is  is a tightly packed array of 988 TeO2 bolometers operated at 10 mK  in the Gran Sasso National Underground Laboratory in Italy. The main goal of the experiment is to search for previously undetected neutrinoless double beta decay in 130Te. CUORE also searches for dark matter and other rare, low-energy events. The CUORE group at Yale has been responsible for the design, construction, and commissioning of the CUORE Detector Calibration System, in the analysis and simulation of CUORE and CUORE-0 data, and in research and development for CUPID, the successor to CUORE. 

CUORE Upgrade with Particle IDentification (CUPID)

Links:  INFN websiteYale websiteKarsten HeegerReina Maruyama

CUORE muon R&D for CUPID.  From

CUPID will use to CUORE infrastructure for a bolometric experiment that is able to operate in the zero-background conditions and explore the inverted hierarchy of neutrino masses, searching for the violation of the lepton number and the Majorana neutrino.  The Yale team is currently re designing a muon veto system for CUORE that will assist in reaching the background goals for CUPID.

Daya Bay Reactor Neutrino Experiment (Daya Bay)

Links:  Daya Bay websiteKarsten Heeger

Daya Bay Reactor detectorDaya Bay is a US-China-Russia collaboration to search for and measure the yet unknown neutrino mixing angle theta13. The experiment is located at the Daya Bay nuclear power plant near Hong Kong, China.  The Yale group has overall responsibility in the US for the design and construction of the antineutrino detectors and is involved in data analysis and measurements. Together with the University of Wisconsin Physical Sciences Laboratory, the Yale group oversaw the assembly and installation of the antineutrino detectors at Daya Bay. 

Deep Underground Neutrino Experiment (DUNE) 

Links:  Fermilab websiteYale websiteBonnie Fleming

// is undertaking R&D for DUNE, a planned neutrino experiment with a detector composed of multiple LArTPCs that is projected to be in operation in 2022. This experiment will send a high energy neutrino beam over a distance of 1,300 km from Fermilab in Batavia, IL to the Sanford Underground Research Facility (SURF) in Lead, South Dakota.  Dune will be used to study low-background physics, such as proton decay and supernova detection, to measure the parameters that characterize three-flavor neutrino oscillations, and to study a phenomenon known as CP-violation, which may help explain the matter-antimatter imbalance in the universe and determine the relative neutrino mass-differences.

The Enriched Xenon Observatory (EXO-200)

Links:  EXO-200 website, David Moore

EXO TPCEXO-200 is a detector which contains ~150 kg of liquid 136Xe in a radiopure time projection chamber (TPC) installed underground at the Waste Isolation Pilot Plant (WIPP) in Carlsbad, NM.  EXO-200 is searching for the extremely rare neutrinoless double beta decay of 136Xe, which can only occur if neutrinos are Majorana particles — i.e. if there is no fundamental difference between a neutrino and antineutrino.  Observing neutrinoless double beta decay would provide direct evidence for new physics beyond the Standard Model of particle physics.  It would also have implications for theories attempting to describe the nature of neutrinos, how neutrinos acquire their masses, and how the small excess of matter over antimatter was generated in the early universe.


Links:  IceCubeReina Maruyama

Felipe Pedreros, IceCube/NSFIceCube is the world’s largest neutrino detector, encompassing a cubic kilometer of ice at depths between 1,450 and 2,450 meters at the South Pole. IceCube uses 5160 photomultiplier tubes (PMTs) to search for neutrinos from the most violent astrophysical sources: events like exploding stars, gamma-ray bursts, and cataclysmic phenomena involving black holes and neutron stars. IceCube is a powerful tool to search for dark matter and could reveal the physical processes associated with the enigmatic origin of the highest energy particles in nature. In addition, exploring the background of neutrinos produced in the atmosphere, IceCube studies the neutrinos themselves; their energies far exceed those produced by accelerator beams.  

Liquid Argon TPC in a Testbeam (LArIAT)

Links:  Fermilab websiteYale websiteBonnie Fleming

// is a project at Fermilab to calibrate the Liquid Argon Time Projection Chamber (LArTPC) technology.  LArIAT uses the repurposed ArgoNeuT TPC in the Fermilab Test Beam Facility (FTBF).


Micro Booster Neutrino Experiment (MicroBooNE)

Links:  Fermilab websiteYale websiteBonnie Fleming

// is a short baseline accelerator neutrino oscillation experiment at Fermilab designed to investigate the source of the low energy excess observed by the MiniBooNE experiment, perform a unique set of low energy neutrino cross section measurements, and conduct R&D towards development of massive LArTPC detectors. Yale’s roles include fabrication and assembly of the TPC and DAQ systems, development of the analysis techniques and tools necessary to analyze the data, and oversight of the collaboration.


Links:  nEXO websiteDavid Moore

nEXO drawingnEXO is the multi-ton successor to EXO-200 (see above), which will search for neutrinoless double beta decay with substantially improved sensitivity.  nEXO is currently in the R&D phase.  The Yale group is working on simulations for nEXO as well as lab tests of new readout techniques for large liquid Xe detectors.

Project 8

Links:  Project 8 website, Yale websiteKarsten Heeger

P8 from P8 websiteProject 8 utilizes a novel technique dubbed Cyclotron Radiation Spectroscopy (CRES) to perform precision beta-electron spectroscopy from a gaseous Tritium source in an effort to measure the effective neutrino mass. Totaling 9 institutions, the Project 8 collaboration has for the first time successfully measured single-electron radiation directly. This fundamentally new approach to precision beta spectroscopy is set to push the current limit on sensitivity in direct neutrino mass experiments.   Project 8 is led by Prof. Karsten Heeger from Wright Laboratory and the physical experiment is located at the University of Washington in Seattle.  The Yale team supports the digitization and ongoing development of algorithms in the data analysis, as well works on a detailed Monte Carlo simulation of the CRES experiment to understand and optimize the energy resolution of the detected electrons.

Precision Oscillation and Spectrum Experiment (PROSPECT)

Links:  PROSPECT websiteKarsten Heeger

PROSPECT-50 by PROSPECT collaborationPROSPECT is a reactor neutrino experiment at very short baselines to make a precision measurement of the flux and energy spectrum of antineutrinos emitted from nuclear reactors. PROSPECT searches for the oscillation signature of sterile neutrinos and tests our understanding of the emission of antineutrinos from the fission products in a nuclear reactor. The measurements of PROSPECT will test our understanding of the Standard Model of Particle Physics, deepen our understanding of nuclear processes in a reactor, and help develop technology for the remote monitoring of nuclear reactors for safeguard and non-proliferation. 

Short Baseline Near Detector (SBND)

Links:  Fermilab websiteYale websiteBonnie Fleming

// SBND is a near detector experiment being developed on the Booster Neutrino Beamline at Fermilab upstream from MicroBooNE.  While MicroBooNE will determine whether or not the low energy excess observed by MiniBooNE is electrons or photons, SBND will look for this excess at a near location to look for a baseline dependence of what MicroBooNE observes.  The Yale team co-founded the experiment and is involved in the design of the SNBD detector and sensitivity studies.  The Yale team is also constructing components of the TPC at Wright Lab, including  the TPC field shaping system, the high voltage feedthrough and part of the scintillation light collection system.


Francesco Iachello’s work has been dedicated to the study of symmetries in physics through the introduction of models based on symmetry and their application to physical systems.  Prof. Iachello is co-discoverer (with A. Arima) of the interacting boson model of nuclei. He also introduced supersymmetry in nuclei, developed the vibron model of molecules,  introduced symmetries at the critical point of phase transitions, and co-introduced the concept of excited states quantum phase transitions.  In recent years, Professor Iachello has further developed the theory of double beta decay, with and without the emission of neutrinos. With J. Barea, he provided a calculation of nuclear matrix elements (NME) within the framework of the interacting boson model (IBM-2).  With J. Kotila, he provided a calculation of phase space factors (PSF). His current research in neutrino physics is the study of mechanisms of neutrino-less double beta decay other than the mass mechanism, in particular:  the emission and reabsorption of hypothetical sterile neutrinos, the emission of a scalar particle (Majoron), and, with L. Graf, the contribution of hitherto unknown dimension-6 and dimension-9 effective operators.