The muon component in The muon component in extensive air showers extensive air showers and its relation to and its relation to hadronic multiparticle hadronic multiparticle production production Christine Meurer Johannes Blümer Ralph Engel Andreas Haungs Markus Roth and the HARP Collaboration HARP Detector, CERN ger Observatory, Argentina
30
Embed
The muon component in extensive air showers and its relation to hadronic multiparticle
The muon component in extensive air showers and its relation to hadronic multiparticle production. Auger Observatory, Argentina. Christine Meurer Johannes Blümer Ralph Engel Andreas Haungs Markus Roth and the HARP Collaboration. HARP Detector, CERN. Outline. - PowerPoint PPT Presentation
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
The muon component in The muon component in extensive air showers extensive air showers
and its relation to and its relation to hadronic multiparticle hadronic multiparticle
productionproduction
Christine Meurer Johannes BlümerRalph EngelAndreas HaungsMarkus Roth
andthe HARP Collaboration HARP Detector, CERN
Auger Observatory, Argentina
HSS 08.09.2006 Fermilab/USA Christine Meurer 2/30
Auger
Outline
• Relation of muons in extensive air showers (EAS) to hadronic interactions
• Comparison: EAS – fixed target experiment
• Investigation of phase space
• Existing accelerator data
• New measurements: NA49 and HARP
• Conclusions and outlook
HSS 08.09.2006 Fermilab/USA Christine Meurer 3/30
Auger
Motivation
Interpretation of CR data Interpretation of CR data relies heavily on MC relies heavily on MC simulationssimulations
MC uncertainties arise MC uncertainties arise predominantly from predominantly from hadronic interaction modelshadronic interaction models
MuonsMuons are one of the main are one of the main ingredients to infer E, Aingredients to infer E, A
Muon component is very Muon component is very sensitive to hadronic sensitive to hadronic interactionsinteractions
Which hadronic interactions are of major Which hadronic interactions are of major importance for muon production?importance for muon production?
HSS 08.09.2006 Fermilab/USA Christine Meurer 4/30
Auger
Composition at the knee
KASCADET. Antoni et al.Astropart.Phys.24(2005)1
Differences mainly due to muon Differences mainly due to muon productionproduction
or
total
HSS 08.09.2006 Fermilab/USA Christine Meurer 5/30
Auger
Muon production in EASproton E =10proton E =101515eV eV = 0°= 0°Primary
• On average 6 interactions before muon productionOn average 6 interactions before muon production• Number of generations increases with smaller Number of generations increases with smaller
muon energy thresholdmuon energy threshold
number of generations
HSS 08.09.2006 Fermilab/USA Christine Meurer 6/30
Auger
Muon energy on ground
lateral distance R
Primaryparticle
Core
p
+
+
+
e-e+
+
00
-
-
p-
-
-
n
e-e+
p
+
p
-
EE smaller for larger smaller for larger distancesdistances
proton E =10proton E =101515eV eV = 0°= 0°
muon energy
HSS 08.09.2006 Fermilab/USA Christine Meurer 7/30
Auger
Relation of muons to hadronic interactions
Last interaction
p
++
+
++
e-e+
+
00
-
-
p
--
-
-
n
e-e+
p
+
p
-
proton E =10proton E =101515eV eV = = 0°0°GHEISHAGHEISHA QGSJET01QGSJET01
mother
detected muon
grandmother
grandmother motherpion 72.3% 89.2%
nucleon 20.9% -
kaon 6.5% 10.5%
grandmother energy
HSS 08.09.2006 Fermilab/USA Christine Meurer 8/30
Auger
EAS vs fixed target experiment
+ Several targets Several targets + Forward direction accessibleForward direction accessible+ Relevant energy range: 8-1000 GeV Relevant energy range: 8-1000 GeV
Transverse momentum of and Kpptt distribution in EAS similar to distribution in EAS similar to pptt distribution in distribution in fixed target fixed target simulation. simulation. → → Low transverse Low transverse momenta of interestmomenta of interest
C.Alt et al. (NA49 collaboration) hep-ex/0606028C.Alt et al. (NA49 collaboration) hep-ex/0606028
Error of NA49 data:Error of NA49 data:stat. error stat. error ~ 5%~ 5%syst. error syst. error ~ 5%~ 5%
Comparison: models – data:Comparison: models – data:SIBYLL and QGSJET-II: SIBYLL and QGSJET-II: reasonable agreement with datareasonable agreement with dataQGSJET-01: QGSJET-01: overestimation of factor ~ 1.5overestimation of factor ~ 1.5
Ongoing analysis: p+C @ 12 GeV/cOngoing analysis: p+C @ 12 GeV/cSelection of secondary particles (Selection of secondary particles () ) in forward hemisphere using the drift in forward hemisphere using the drift chambers.chambers.No of events: No of events: 1,000k1,000kNo of events after cuts:No of events after cuts: 450k 450k
0 1 2 3 4 5 6 7 8 9 10
p
e
k
TOFCERENKOV
TOF CERENKOV
CERENKOVCALORIMETER
Separation of particle Separation of particle types using different types using different detector componentsdetector components
Ongoing analysis: p+C @ 12 GeV/cOngoing analysis: p+C @ 12 GeV/cSelection of secondary particles (Selection of secondary particles () ) in forward hemisphere using the drift in forward hemisphere using the drift chambers.chambers.No of events: No of events: 1,000k1,000kNo of events after cuts:No of events after cuts: 450k 450k
0 1 2 3 4 5 6 7 8 9 10
p
e
k
TOFCERENKOV
TOF CERENKOV
CERENKOVCALORIMETER
Separation of particle Separation of particle types using different types using different detector componentsdetector components