Recent & Past Highlights

Dr. Zohreh Parsa Started the Neutrino CPv/ LBN Studies at BNL in 1998. This page includes part of her collaborative work. Dr.William Marciano Neutrino Physics, etc.; Awarded J. J. Sakurai Prize for Theoretical Particle Physics (2002) Dr. Nicholas Samios Early measurements of neutrino electron elastic scattering etc.;  Awarded Gian Carlo Wick Gold Medal   (2009) Dr. Raymond Davis Awarded 2002 Physics Nobel Prize for detecting Solar Neutrinos! Dr. Maurice Goldhaber
Experiment, revealed ν's to be left-handed, property known as "spin" Awarded National Medal of Science.
Dr. Melvin Schwartz Awarded Nobel Prize for Discovery of the Muon-Neutrino (1988).

Neutrino Physics & Experiment

Neutrino physics has had an interesting history. In 1930 Dr. Pauli postulated the existence of the (electron) neutrino, in 1956 this was confirmed by Drs. Reines and Cowan using a nuclear reactor source of antineutrinos. In 1962, a second distinct (muon) neutrino was shown to exist in a BNL experiment. For that discovery Nobel Prize was awarded to Drs. Lederman, Schwartz and Steinberger. In 1995, the third, (tau) neutrino was detected at FNAL. In parallel, Dr. Ray Davis' studies of solar neutrinos confirmed understanding of stellar dynamics modulo a 2/3 flux deficit that later was recognized as a result of neutrino oscillations among the three flavors of neutrinos. properties of those oscillations were further unveiled with followup solar, atmospheric, reactor and accelerator neutrino studies . The discovery of oscillations, detection of 19 neutrino events from supernova 1987a by the old IMB and Kamiokande water cerenkov detectors confirmed the theory of supernova explosions. The WMAP experiment has started to see imprints of neutrino mass effects on the cosmic microwave background radiation left from the Big Bang.

Introduction

In 1998 Dr. Zohreh Parsa at BNL started the Neutrino /CP Violation studies, that envisioned sending a very intense neutrino beam from Brookhaven National Laboratory on Long Island, New York through the earth to a (1200 km < L < 4000 km) far away underground multipurpose large detector capable of: making precision measurements of all the (ν) neutrino oscillation parameters providing a major advance in ν science; search for proton decay; and observation of natural sources of neutrinos such as supernova. The key to this approach is a very long distance for the oscillations to develop and interfere. Length (L) of the Baseline defines the physics you can do,   once chosen, can not be changed without establishing a complete new facility.

By measuring muon neutrino disappearance as well as electron neutrino appearance, such a project would be capable of determining all 3 generation mixing angles, mass hierarchy, along with magnitude of the CP violation (e.g.by measuring CKM phase & explicitly observing differences in the muon neutrino and muon anti-neutrino oscillations). No existing or proposed future experiment so far has such capability.

Very Long Baseline Neutrino Experiment

Using a wide band muon neutrino beam from BNL to a 2540 km baseline (with 0.5 megaton water Cherenkov) detector at Homestake gold Mine in South Dakota was our first study for "very Long Baseline Neutrino Experiment" (LBNE).

Potentials of intense neutrino beams from BNL (and FNAL) to Long Baseline Detectors at Homestake (SD), Henderson (Co) and Cascades (WA) were also studied (as competition for possible (DUSEL) Deep Underground Science and Engineering Laboratory Site grew). Some of our neutrino simulations are illustrated below. With "Firefox" browser |click| to see (rotating) Figs. Reload browser if blank & for more Figs.

Fig. 1    (Top Figure) shows CP Phase Variations, in Probability vs Energy plot(s).   Fig. 2    (Lower Fig.) shows variation of parameters, e.g. variation of L (Baseline) distance from neutrino source to the detector, in the Probability vs Energy plot.

Our Physics and Detector R & D collaborations has continued. Although the interest and Proposals for a LBNE with neutrino source at BNL to a far Detector (L=2540 km away) at Homestake (SURF, Lead, S.D.) grew, Such a possibility (at BNL) became less likely due to years of funding changes & delays.


Fig. 3    Shows BNL, FNAL and 3 possible DUSEL Detector Sites, Homestake (SD), Henderson (CO), and Cascades (WA). DUSEL selected site is the Homestake Mine in South Dakota, a distance of 2540 km from BNL and close to 1300 km from FNAL


Fig. 4    Shows Super-Kamiokande (largest neutrino detector to date) is 50-kiloton water Cherenkov detector, (placed 3300 feet underground in a cavern ~ 40 meters high and 40 meters wide), filled with water and photomultiplier tubes (PMTs) on its walls.

LBNE (very Long-Baseline Neutrino Experiment) would greatly advance research at the Intensity Frontier. In 2008, High Energy Physics P5 panel recommended to pursue a world class neutrino program with a large detector and a high intensity neutrino beam.

LBNE Reconfiguration-- with ν source at FNAL

Using a high intensity accelerator neutrino beam from Fermilab (FNAL) to a (L=1287.475 km=800 miles baseline) liquid argon TPC detector at SURF (Homestake) is the LBNE reconfiguration. The goals for this program are determination of leptonic CP violation, the neutrino mass hierarchy, and underground physics.

On Dec 10, 2012, DOE granted Critical Decision 1 (CD-1) approval to the first phase of LBNE, which includes construction of a neutrino beamline at Fermilab (where the neutrino beam would travel through 800 miles of earth to a (near-surface) far detector at Sanford Lab in Lead, S.D. For Proposed LBNE Factsheet |click|

For Brookhaven National Laboratory (BNL) DOE's approval of CD-1 is an important milestone after over decade of work. The initial construction for the beamline is to begin in 2015; CD-2 approval is expected in spring of 2016. Experiment is scheduled to begin taking data in 2023. ( Additional resources would allow placeing of the far detector underground in the first phase to improve accuracy of the long-baseline oscillation measurements.)
*** Left Tabs provide additional informationn on LBNE (with beam from FNAL to Detecor at Lead, S.D.), etc.


Fig. 5    Drs. Z. Parsa, W. Marciano and R. Wilson in Henderson (Molybdenum Mine), a proposed Underground Lab site in CO.

Neutrino (alias Neutrinos) updated: 1999-2014   Dr. Zohreh Parsa, Physics Dept. 510A, Brookhaven National Lab, Upton NY 11973.
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