Analysis of Ultra High Energetic Cosmic Rays measured in monocular - - PowerPoint PPT Presentation

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Analysis of Ultra High Energetic Cosmic Rays measured in monocular mode with the fmuorescence telescopes at the Pierre Auger Observatory

Yes, FDMono it is

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Motivation

• FD Mono Event from April
• Outside of SD array
• Almost 100 EeV
• Well reconstructed

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Motivation

• Mono: Events without SD and in only
• ne eye
• Simulation of effective area already

done in 2004 by Sergio Petrara

• Extrapolation to UHECR →

potentially lots of statistics not yet used, but ... How reliable is the reconstruction without the additional data from SD or a second eye?

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Quality of Mono reconstruction

• Sample of Hybrid events used to

define quality cuts for Mono

• Hybrid reconstruction seen as “true”,

deviations from it as problems of the Mono reconstruction

• Roughly binned spectrum → already

visible migration effect into emptier bins

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Quality of Mono reconstruction

FDMono uses two step reconstruction:

• SDP fit works well most of the time, but not always

→constraints on χ2 of SDP

• Four-Parameter time fit → often underdetermined due to

missing additional info by SD Also no second FD eye for geometric core location → core Position on SDP often reconstructed incorrectly and with wrong energy, leads to subsequent errors in

• ther variables

→ cut on the χ2 of time fit

t=t 0+( R p c )∗tan ( χ0−χ 2 )

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Cuts

• Exclusion of HEAT because of
• utliers
• Unrealistic xMax values

excluded by energy dependent cuts

• χ2

SDP/NDF < 4

• Cut on difference of fitted χ2 and

χ2 of a potential linear fit → strongest selection criteria

• Efficiency of total cuts at high

energies ~ 60%