Aspen

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The air-shower experiment KASCADE-Grande
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Experiment KASCADE-Grande KArlsruhe Shower
Core and Array DEtector Grande and LOPES
Measurements of air showers in the energy range
E0 100 TeV - 1 EeV
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KASCADE multi-parameter measurements

• - energy range 100 TeV 80 PeV
• - up to 2003 4?107 EAS triggers
• - large number of observables
• electrons
• muons (_at_ 4 threshold energies)
• hadrons

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KASCADE energy spectra of single mass groups
Measurement KASCADE array data 900 days 0-18o
zenith angle 0-91m core distance lg Ne gt 4.8 lg
Nmtr gt 3.6 ? 685868 events
Searched E and A of the Cosmic Ray
Particles Given Ne and Nm for each single event
? solve the inverse problem with
y(Ne,Nmtr) and x(E,A)
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KASCADE Unfolding procedure
- kernel function obtained by Monte Carlo
simulations (CORSIKA) - contains shower
fluctuations, efficiencies, reconstruction
resolution
KASCADE collaboration, Astroparticle Physics 24
(2005) 1-25, astro-ph/0505413
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KASCADE results
- same unfolding but based on two different
interaction models - SIBYLL 2.1 and QGSJET01
(both with GHEISHA 2002) all embedded in CORSIKA
SIBYLL
QGSJet
KASCADE collaboration, Astroparticle Physics 24
(2005) 1-25, astro-ph/0505413
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KASCADE results confirmation
- same unfolding but based on two different low
energy interaction models and different zenith
angle ranges - GHEISHA 2002 and FLUKA (both with
QGSJET01) - 0-18o, 18-25.9o, 25.9-32.3o (all with
QGSJET01/FLUKA)
- Less dependence for unfolding based on
different low energy hadronic interaction
models - Weak dependence on zenith angular
binning (not significant)
KASCADE collaboration, Astroparticle Physics
(2008), submitted
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KASCADE test of new hadronic interaction
modelsEPOS 1.61
light edge
heavy edge
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KASCADE new hadronic interaction model EPOS

• unfolding based EPOS 1.61 and FLUKA (with
  CORSIKA 6.6)
• correlation with hadronic shower observables

• -) very proton dominant, but knee caused by light
  primaries
• -) no iron needed
• EPOS predict too many muons or too less electrons
  (for KASCADE)
• EPOS delivers not enough hadronic energy to
  observation level

KASCADE collaboration, ICRC 2007 J.Hörandel,
this conference
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KASCADE Summary
all-particle spectra
-) knee caused by light primaries ? composition
gets heavier across knee -) positions of knee
vary with primary elemental group -) relative
abundancies depend strongly on high energy
interaction model -) result only weakly dependent
on low energy interaction model -) result
consistent for different data sets -) no
(interaction) model can describe the data
consistently -) all-particle spectra agree inside
uncertainties (EPOS a bit lower) -) proton
spectra agree with direct measurements (not for
EPOS)
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Motivation for measurements 100 1000 PeV

• - Iron knee ?
• - second knee ??
• transition galactic-
• extragalactic CR ??

?
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KASCADE-Grande multi-parameter measurements

• KASCADE Grande
• ?energy range
• 100 TeV 1 EeV
• large area 0.5 km2
• Grande 37x10 m2 scintillators
• Piccolo trigger array

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KASCADE-Grande Single event measurement
lateral distribution of a single event measured
by KASCADE-Grande E0?2?1017eV, ?33o
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KASCADE-Grande Efficiency

• Common events
• (all detector components)
• measure since December 2003
• Trigger 7of 7 stations at one
• of 18 hexagons

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KASCADE-Grande Reconstruction

• 1) core position and angle-of-incidence
• from Grande array data
• ?
• 2a) shower size (charged particles)
• from Grande array data
• 2b) muon number
• from KASCADE muon detectors
• ?
• 3) electron number
• from Grande by subtraction of muon content
• ?
• 4) two dimensional size spectrum
• for the unfolding analysis

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KASCADE-Grande Single event reconstruction
a single event measured by KASCADE-Grande core
(-155,- 401) m log10(Size) 7.0 log10(Sizm)
5.7 No saturation Zenith 24.2 degrees Azimuth
284 degrees Recorded on 8 July 2005 at 1211 (UTC)
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KASCADE-Grande Reconstructionangular, core
shower size (Nch) resolution

• Monte-Carlo studies (QGSJet II / FLUKA)
• s 0.4o angular resolution
• s 5m core resolution
• Sufficient (20) reconstruction accuracies for
  shower size
• Small overestimation (5-10) and small energy
  (size) dependence

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KASCADE-Grande Reconstructionmuon number
(Eµgt230MeV) electron number
Monte-Carlo studies (QGSJet II / FLUKA)

• Muons
• (20) reconstruction accuracy for total muon
  number
• Bias (10-15) in energy (muon number) dependance

• Electrons
• 25-30 reconstruction accuracy for total
  electron number
• Bias (10 overestimation) in energy (size)
  dependance

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KASCADE-Grande Fluctuations
From calibration procedures and From station
density spectra ? Accuracy in particle
density 15
all 37 stations
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KASCADE-Grande Accuracieswith subsample of
common events KASCADE Grande
core
direction
shower size
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KASCADE-Grande lateral distributions
charged particle lateral distribution
muon lateral distribution
preliminary

• performance of measurements stable
• reconstruction and analysis of LDFs possible

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size spectra (charged particles)
preliminary

• stable data taking since 2004, c. 900 days
  effective DAQ time
• performance of array is stable
• reconstruction gives reasonable spectra for all
  angle bins
• careful checks of systematic effects in work

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muon number spectra (Nµ Eµgt230MeV)
preliminary

• stable data taking since 2004, c. 900 days
  effective DAQ time
• performance of muon reconstruction is stable
• reconstruction gives reasonable spectra for all
  angle bins
• careful checks of systematic effects in work

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electron number spectra (Ne)
preliminary
preliminary

• stable data taking since 2004, c. 900 days
  effective DAQ time
• performance of electron reconstruction works and
  is stable
• reconstruction gives reasonable spectra for all
  angle bins
• careful checks of systematic effects in work

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Way to all-particle energy spectrum constant
intensity cut method CIC (Nch)
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For a given I, get Nch(?)
- Apply cut at constant intensity
preliminary
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Way to all particle energy spectrum constant
intensity cut method CIC (Nch)
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• Correction to angular dependence of shower
  observable

Get attenuation curve parameters
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Way to all particle energy spectrum constant
intensity cut method CIC (Nch)
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- Nch(20º) of each event
Shower size spectrum
preliminary
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Way to all particle energy spectrum constant
intensity cut method CIC (Nch)
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From Simulations shower size energy
correlation (power law assumption)
- Perform conversion into energy
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Way to all particle energy spectrum constant
intensity cut method CIC (Nch)
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- Energy spectrum
QGSJET II hadronic interaction model
preliminary
Sources of uncertainty 1) Bias correction
functions 2) CIC method 3) Energy vs Nch
relation 4) Influence of MC statistics 5)
Influence of spectral index in MC sample 6)
Composition assumption .work to do!
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all particle energy spectrum constant intensity
cut method CIC (Nµ)
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Nµ(24º) of each event
Apply cut at constant J?
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Get attenuation curves
For a given J?, get N?(?)
?E/E 26.8
?E/E 21.9
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?E/E 21.8
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Energy spectrum
?E/E 22
Conversion into energy
preliminary
J.C.Arteaga, this conference
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muon reconstruction at inclined showers
preliminary

• muon number reconstruction possible up to 70o
• investigation of attenuation of muon component
• model tests
• Increasing of KASCADE-Grande statistics

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energy reconstruction by S(500)
CIC corrected to 20o
preliminary
KASCADE-Grande data lt40o
Case of KASCADE-Grande S(500) is optimal ?
Method works and is stable ? Independent energy
estimation ? Cross checks with standard
reconstruction
QGSJet II/ FLUKA
G.Toma, this conference
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KASCADE-Grande unfolding analysis
preliminary
c.4300 events gt 1017eV

• Unfolding of 2-dimensional shower size spectrum
  possible
• ? energy composition
• still improvements in systematics needed
• higher statistics

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Unfolding at KASCADE-Grandemethod applied to
fully simulated test spectra
Simulation

• QGSJet II / FLUKA simulations (0-18o)
• Present available statistics and extrapolation of
  KASCADE results used
• ? Unfolding of 2-dimensional shower size spectrum
  also at KASCADE-Grande possible
• ? energy composition
• still improvements in systematics needed
• higher statistics(combining all zenith angles)

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muon density investigations
Very preliminary
preliminary
7.0 lt log10(Ne) lt 7.3
preliminary

• muon (local) density reconstruction possible for
  different distances
• composition sensitivity
• model tests

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HE Muon Measurements at KASCADE-Grande

• Central Detector muon facility
• Eµthresh 2400 MeV
• Muon Density measurements rm2.4GeV
• Lateral distributions
• Model tests (muon energy spectrum)
• Rr2.4/0.23 rm2.4GeV / rm0.23GeV

• Muon Tracking Detector
• Eµthresh 800 MeV
• Measurement of radial and tangential
  angles rm,tm
• ?Muon production height
• ?Lateral distributions
• Model tests (pseudorapidity)
• hm -ln(z/2) z pt/pll sqrt(r2 t2)

P.Doll, J.Zabierowski, this conference
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KASCADE-Grande

• Conclusions
• around knee KASCADE results
• ?knee is caused by light primary elements
• ?cosmic rays are isotropic around the knee
• interaction models have to be further improved
  (w/o new physics)
• knee most probable due to mixture of
  acceleration and propagation effects
• (possible key points anisotropy studies for
  individual elements)
• now same quality for 10-1000 PeV by
  KASCADE-Grande to identify
• the iron-knee and transition
  galacticextragalactic cosmic rays!
• KASCADE-Grande energy spectrum and composition
  on the way
• new detection techniques?
• ? LOPES radio detection of air showers

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