Author: Steven C. CorbatoPublisher:
ISBN:
Category :
Languages : en
Pages : 346
Book Description
Search for Anisotropies in the Underground Cosmic Ray Muon Flux
Author: Steven C. CorbatoProbing Cosmic Ray Anisotropy with Atmospheric Neutrinos
Author: Elizabeth J. WillsPublisher:
ISBN:
Category : Anisotropy
Languages : en
Pages : 181
Book Description
In the hundred years that have followed the discovery of cosmic rays, more about them remains unknown than known. Many concerted efforts are currently underway to detect cosmic rays using a variety of detection methods in space, on the surface of Earth, and deep underground. Of the many remaining mysteries, the one addressed in this work is the anisotropy in arrival directions of the cosmic rays incident on the atmosphere. This behaviour has been observed in both hemispheres of the planet, at high significance, from 1 TeV - 1 EeV energy ranges, at angular scales from 5 degrees to 180 degrees, and displays no time variation. It is measured consistently as a 0.1% over- and under-fluctuation. This work presents the first neutrino analysis of cosmic ray arrival directions so far, specifically, in the northern hemisphere. The analysis is done with an atmospheric neutrino dataset which was specifically designed for this analysis and composed of neutrinos detected by the IceCube South Pole Neutrino Observatory from 2011-2016. The goal of the search was to detect cosmic ray anisotropy as observed in atmospheric muons, but this time, in atmospheric neutrinos. To this end, a new atmospheric neutrino dataset was created using machine learning, aiming to increase data acceptance rates by optimizing sacrifices in purity and angular acceptance. The standard analysis techniques were carried out, along with a new log-likelihood method developed to improve sensitivity in a lower-statistics realm. While no signal was detected in this analysis, the analysis methodology has been developed and tested. We project that with a total of twelve years of IceCube data will be required to be sensitive to a dipole anisotropy at the level previously reported by the Tibet-AS[gamma] Collaboration. Detection of cosmic ray anisotropy in the neutrino channel would allow for verification of known cosmic ray shower physics, and particle propagation. The neutrinos could allow us to probe the anisotropy in a new way. If the signal deviates, there could be new physics to discover. The method and data selection are developed, and in several years, new developments will be made towards unraveling the mystery of cosmic ray anisotropy with neutrinos.
Search for Cosmic Ray Point Sources and Anisotropy Measurement with the L3+C Experiment
Author: Renzo G.E. RamelliMatter, Anti-matter And Dark Matter, Proceedings Of The Second International Workshop
Author: Roberto BattistonPublisher: World Scientific
ISBN: 9814487775
Category : Science
Languages : en
Pages : 269
Book Description
This book presents the progress in cosmic ray physics following the recent results obtained by balloon, satellite and underground experiments. The following topics are reviewed: Composition and propagation of cosmic rays, trapping of charged particles in the earth's magnetic field, atmospheric neutrinos, and high energy photon measurements in space.
An Apparatus for Measuring Large Scale Cosmic Ray Anisotropy Through Water Cherenkov Muon Detection
Author: Malcolm McCarthyTAUP 91
Author: A. MoralesPublisher: Elsevier
ISBN: 1483257142
Category : Science
Languages : en
Pages : 539
Book Description
TAUP 91 covers the proceedings of the Second International Workshop on Theoretical and Phenomenological Aspects of Underground Physics, held in Toledo, Spain on September 9-13, 1991. The book focuses on the processes, methodologies, reactions, and transformations involved in underground physics. The selection first offers information on the fundamental issues in particle astrophysics and an overview of the problems related to general cosmology. Topics include connections between particle physics, astrophysics, and cosmology, stellar physics and particles, astrophysical ages, cosmic background radiation, and abundances of light elements. The text also takes a look at big bang nucleosynthesis constraints on new physics and microwave background radiation. The publication ponders on very wide band interferometric gravitational wave antenna and search for stellar gravitational collapse by macro. The text also examines high energy cosmic neutrinos of acceleration and non-acceleration origin; tests of general relativity and Newtonian gravity at large distances and the dark matter problem; and nuclear form factors for the scattering of neutralinos. The selection is a valuable reference for readers interested in underground physics.
The Calibration of an Ultra-high Energy Muon Hodoscope and Search for Cosmic Gamma Ray Anisotropies
Author: Thomas K. McCarthyPublisher:
ISBN:
Category : Liquid scintillators
Languages : en
Pages : 254
Book Description
Deep Underground Science and Engineering Lab
Author: H. NelsonPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
In this report we have described the broad and compelling range of astrophysical and cosmological evidence that defines the dark matter problem, and the WIMP hypothesis, which offers a solution rooted in applying fundamental physics to the dynamics of the early universe. The WIMP hypothesis is being vigorously pursued, with a steady march of sensitivity improvements coming both from astrophysical searches and laboratory efforts. The connections between these approaches are profound and will reveal new information from physics at the smallest scales to the origin and workings of the entire universe. Direct searches for WIMP dark matter require sensitive detectors that have immunity to electromagnetic backgrounds, and are located in deep underground laboratories to reduce the flux from fast cosmic-ray-muon-induced neutrons which is a common background to all detection methods. With US leadership in dark matter searches and detector R & D, a new national laboratory will lay the foundation of technical support and facilities for the next generation of scientists and experiments in this field, and act as magnet for international cooperation and continued US leadership. The requirements of depth, space and technical support for the laboratory are fairly generic, regardless of the approach. Current experiments and upgraded versions that run within the next few years will probe cross sections on the 10{sup -45}-10{sup -44} cm{sup 2} scale, where depths of 3000-4000 m.w.e. are sufficient to suppress the neutron background. On the longer term, greater depths on the 5000-6000 level are desirable as cross sections down to 10{sup -46} cm{sup 2} are probed, and of course, if WIMPs are discovered then building up a statistical sample free of neutron backgrounds will be essential to extracting model parameters and providing a robust solution to the dark matter problem. While most of the detector technologies are of comparable physical scale, i.e., the various liquid and solid-state detector media under consideration have comparable density, a notable exception is the low-pressure gaseous detectors. These detectors are very likely to play a critical role in establishing the galactic origin of a signal, and so it is important to design the lab with this capability in mind. For example, for a WIMP-nucleon cross section of 10{sup -43} cm{sup 2} (just below the present limit [20]), 100 of the current DRIFT-II modules of 1 m{sup 3} at 40 torr CS{sub 2} [63] would require a two-year exposure [61] to get the approximately 200 events [64] required to establish the signal's galactic origin. While detector improvements are under investigation, a simple scaling for the bottom of the MSSM region at 10{sup -46} cm{sup 2} would require a 100,000 m{sup 3} detector volume. If a factor of 10 reduction in required volume is achieved (e.g., higher pressure operation, more detailed track reconstruction, etc.) then an experimental hall of (50 m){sup 3} could accommodate the experiment. Because the WIMP-nucleon cross section is unknown, it is impossible to make a definitive statement as to the ultimate requirements for a directional gaseous dark matter detector, or any other device, for that matter. What is clear, however, is that whatever confidence one gives to specific theoretical considerations, the foregoing discussion clearly indicates the high scientific priority of, broad intellectual interest in, and expanding technical capabilities for increasing the ultimate reach of direct searches for WIMP dark matter. Upcoming experiments will advance into the low-mass Supersymmetric region and explore the most favored models in a complementary way to the LHC, and on a similar time scale. The combination of astrophysical searches and accelerator experiments stands to check the consistency of the solution to the dark matter problem and provide powerful constraints on the model parameters. Knowledge of the particle properties from laboratory measurements will help to isolate and reduce the astrophysical uncertainties, which will allow a more complete picture of the galactic halo and could eventually differentiate between, say, infall versus isothermal models of galaxy formation. The scientific landscape of dark matter, which spans particle physics, astrophysics and cosmology, is very rich and interwoven. Exploring this exciting program following an initial detection will need many observables and hence a range of capabilities for followup experiments including different targets to sort out the mass and coupling of the WIMP, and directional sensitivity to confirm its galactic origin and open the age of WIMP astronomy. Clearly, this broad and fascinating program is ideally suited to the multi-decade span of DUSEL.
The Cosmic Muon Flux in the ATLAS Detector at the Large Hadron Collider
Author: Ewan Chin HillPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Many ATLAS analyses study events with muons in them including those searching for the Higgs boson and new physics. Cosmics muons, however, can also occasionally enter the detector and mimic the trajectory of a muon from one of the collisions produced by CERN's Large Hadron Collider. By understanding the different ways ATLAS triggers on, collects, reconstructs, and analyses data from cosmic rays and collisions, the flux of cosmic muons with transverse momenta above 20 GeV in the central region of the detector was measured to be 1.34 ± 0.06 (stat.) s^?1 m^?2 . At the same time the cosmic muon charge ratio has been measured to be 1.3 ± 0.1 (stat.). This measurement of the cosmic muon flux in ATLAS is the first step in quantifying the sizes of the cosmic muon backgrounds to various physics analyses that look for events with muons.
Author: