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.
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.
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
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).
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.
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
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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
DUSEL selected site is the Homestake Mine in South Dakota, a
distance of 2540 km from BNL and close to 1300 km from
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
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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