Records |
Author |
Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
A search for anisotropy in the arrival directions of ultra high energy cosmic rays recorded at the Pierre Auger Observatory |
Type |
Journal Article |
Year |
2012 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
04 |
Issue |
4 |
Pages |
040 - 21pp |
Keywords |
ultra high energy cosmic rays; cosmic ray experiments |
Abstract |
Observations of cosmic rays arrival directions made with the Pierre Auger Observatory have previously provided evidence of anisotropy at the 99% CL using the correlation of ultra high energy cosmic rays (UHECRs) with objects drawn from the Veron-Cetty Veron catalog. In this paper we report on the use of three catalog independent methods to search for anisotropy. The 2pt-L, 2pt+ and 3pt methods, each giving a different measure of self-clustering in arrival directions, were tested on mock cosmic ray data sets to study the impacts of sample size and magnetic smearing on their results, accounting for both angular and energy resolutions. If the sources of UHECRs follow the same large scale structure as ordinary galaxies in the local Universe and if UHECRs are deflected no more than a few degrees, a study of mock maps suggests that these three method can efficiently respond to the resulting anisotropy with a P-value = 1.0% or smaller with data sets as few as 100 events. using data taken from January 1, 2004 to July 31, 2010 we examined the 20, 30, ... , 110 highest energy events with a corresponding minimum energy threshold of about 49.3 EeV. The minimum P-values found were 13.5% using the 2pt-L method, 1.0% using the 2pt+ method and 1.1% using the 3pt method for the highest 100 energy events. In view of the multiple (correlated) scans performed on the data set, these catalog-independent methods do not yield strong evidence of anisotropy in the highest energy cosmic rays. |
Address |
[Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Diogo, F.; Espadana, J.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Santos, E.; Tome, B.] Univ Tecn Lisboa, LIP, P-1100 Lisbon, Portugal, Email: auger_spokesperson@fnal.gov |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1475-7516 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000303665000040 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1015 |
Permanent link to this record |
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Author |
PTOLEMY Collaboration (Betti, M.G. et al); de Salas, P.F.; Gariazzo, S.; Pastor, S. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
A design for an electromagnetic filter for precision energy measurements at the tritium endpoint |
Type |
Journal Article |
Year |
2019 |
Publication |
Progress in Particle and Nuclear Physics |
Abbreviated Journal |
Prog. Part. Nucl. Phys. |
Volume |
106 |
Issue |
|
Pages |
120-131 |
Keywords |
PTOLEMY; Relic neutrino; Cosmic Neutrino Background; CNB; Neutrino mass; Transverse drift filter |
Abstract |
We present a detailed description of the electromagnetic filter for the PTOLEMY project to directly detect the Cosmic Neutrino Background (CNB). Starting with an initial estimate for the orbital magnetic moment, the higher-order drift process of E x B is configured to balance the gradient-B drift motion of the electron in such a way as to guide the trajectory into the standing voltage potential along the mid-plane of the filter. As a function of drift distance along the length of the filter, the filter zooms in with exponentially increasing precision on the transverse velocity component of the electron kinetic energy. This yields a linear dimension for the total filter length that is exceptionally compact compared to previous techniques for electromagnetic filtering. The parallel velocity component of the electron kinetic energy oscillates in an electrostatic harmonic trap as the electron drifts along the length of the filter. An analysis of the phase-space volume conservation validates the expected behavior of the filter from the adiabatic invariance of the orbital magnetic moment and energy conservation following Liouville's theorem for Hamiltonian systems. (C) 2019 Elsevier B.V. All rights reserved. |
Address |
[Hochberg, Y.] Hebrew Univ Jerusalem, Racah Inst Phys, Jerusalem, Israel, Email: cgtully@Princeton.EDU |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0146-6410 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000464490900003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3978 |
Permanent link to this record |