14,146 research outputs found
Muon : current status
The muon magnetic anomaly, , plays a special role in
the history of the Standard Model (SM). Precise calculations and measurements
of this fundamental quantity provide a stringent test of the SM and a window to
the physics beyond. In light of the first result published by the Fermilab Muon
experiment, this article reviews the current status of the theoretical
prediction and experimental measurement of the muon anomalous magnetic moment.
It also provides an overview on resulting constraints of associated physics
beyond the SM (BSM), future muon experiments and on the progress of
experiments that are closely connected to the physics of the muon , such
as measurements that could provide complementary information about BSM physics
in the muon sector.Comment: Submitted to Nuclear Physics B for revie
Other Atmospheric Neutrino Experiments
The history and recent progress of atmospheric neutrinos are reviewed. An
emphasis is placed on results from experiments other than Super-Kamiokande.Comment: 8 pages, 10 figures, Contribution to Neutrino 200
History of "Anomalous" Atmospheric Neutrino Events: A First Person Account
The modern picture of the neutrino as a multiple mass highly mixed neutral
particle has emerged over 40 years of study. Best known of the issues leading
to this picture was the apparent loss of neutrinos coming from the sun. This
article describes another piece of evidence that supports the picture; the
substantial reduction of high energy muon type neutrinos observed in nature.
For much of the 40 year period, before the modern picture emerged this
observation was known as the "atmospheric neutrino anomaly", since as will be
seen, these neutrinos originate in the Earth's atmosphere.
This paper describes the discovery of the atmospheric neutrino anomaly. We
explore the scientific context and motivations in the late 1970's from which
this work emerged. The gradual awareness that the observations of atmospheric
neutrinos were not as expected took place in the 1983-1986 period.Comment: 46 pages, 24 figures. To be published in Physics in Perspective
Version 2 has a table of contents, a table of figures and the DOI added The
final publication is available at Springer via
http://dx.doi.org/10.1007/s00016-016-0185-
Detection of Near Horizontal Muons with the HAWC Observatory
The HAWC (High Altitude Water Cherenkov) gamma ray observatory is able to
observe muons with nearly horizontal trajectories. HAWC is located at an
altitude of 4100 meters a.s.l. on the Sierra Negra volcano in Mexico. The HAWC
detector is composed of 300 water tanks, each 7.3 m in diameter and 4.5 m tall,
densely packed over a physical area of 22,000 m. Previous and current
experiments have observed high zenith angle (near horizontal) muons at or near
sea level. HAWC operates as a hodoscope able to observe multi-TeV muons at
zenith angles greater than 75 degrees. This is the first experiment to measure
near horizontal muons at high altitude and with large ( 10 m) separations
for multiple muons. These muons are distinguishable from extensive air showers
by observing near horizontal particles propagating with the speed of light. The
proximity of Sierra Negra and Pico de Orizaba volcanoes provides an additional
measurement of muons with rock overburdens of several km water equivalent. We
will present the angular distribution and rate at which HAWC observes these
muon eventsComment: Presented at the 35th International Cosmic Ray Conference (ICRC2017),
Bexco, Busan, Korea. See arXiv:1708.02572 for all HAWC contribution
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