Latest results and perspectives of the KASCADE-Grande EAS facility

Transcription

1 Latest results and perspectives of the KASCADE-Grande EAS facility 29/6-2/7/2010, Nantes, France Andreas Haungs 1

2 Motivation KASCADE-Grande Knee EeV PeV g-eg? Radio?! KASCADE ev: Origin of the knee? KASCADE-Grande ev: Iron knee (rigidity)? Transition galactic-eg CR? LOPES ev: New detection technique! 29/6-2/7/2010, Nantes, France Andreas Haungs 2

3 KASCADE-Grande = KArlsruhe Shower Core and Array DEtector + Grande and LOPES Measurements of air showers in the energy range E 0 = 100 TeV - 1 EeV radio signal electrons muons (@ 4 threshold energies) hadrons charged particles fast trigger 29/6-2/7/2010, Nantes, France Andreas Haungs 3

4 Model independent multi-parameter analysis - Total muon number and electron number mass estimator - high-energy local muon density energy estimator KASCADE : Astroparticle Physics 16, 373 (2002) KNEE CAUSED BY DECREASING FLUX OF LIGHT ELEMENTS Do we need hadronic interaction models? yes, for normalization of absolute energy and mass scale!! 29/6-2/7/2010, Nantes, France Andreas Haungs 4

5 KASCADE : energy spectra of single mass groups unfolding Searched: E and A of the Cosmic Ray Particles Given: N e and N for each single event solve the inverse problem 29/6-2/7/2010, Nantes, France Andreas Haungs - kernel function obtained by Monte Carlo simulations (CORSIKA) - contains: shower fluctuations, efficiencies, reconstruction resolution KASCADE collaboration, Astroparticle Physics 24 (2005)

6 KASCADE results - same unfolding but based on different hadronic interaction models embedded in CORSIKA SIBYLL QGSJet - all-particle spectrum similar - general structure similar: knee by light component - relative abundances very different for different high-energy hadronic interaction models KASCADE collaboration, Astrop.Phys. 24 (2005) 1, Astrop.Phys. 31 (2009) 86 29/6-2/7/2010, Nantes, France Andreas Haungs 6

7 KASCADE result: new model: EPOS EPOS FLUKA: composition light dominant Knee caused by light elements all-particle spectrum okay - the case for EPOS 1.61: all-particle spectrum not okay very proton dominant EPOS 1.99: Phys.Rev.C74(2006) // KASCADE analysis: Marcel Finger PhD(2010) 29/6-2/7/2010, Nantes, France Andreas Haungs 7

8 KASCADE Summary -) 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 -) no (interaction) model can describe the data consistently -) all-particle spectra agree inside uncertainties (EPOS1.6 a bit lower) -) proton spectra agree with direct measurements (not for EPOS1.6) 29/6-2/7/2010, Nantes, France Andreas Haungs 8

9 Motivation for measurements PeV - Iron knee? - second knee?? - transition galacticextragalactic CR?? 29/6-2/7/2010, Nantes, France Andreas Haungs 9

10 Single event reconstruction core (-155,- 401) m log 10 (N ch ) = 7.0 log 10 (N µ ) = 5.7 No saturation Zenith: 24.2 o Azimuth: 284 o Recorded on 8 July 2005 at 12:11 (UTC) For each event: core and angle of incidence (from Grande) shower size (charged particles) muon number (from KASCADE) local muon density (r) (from KASCADE) local charged density S(500) (charged particles) 29/6-2/7/2010, Nantes, France Andreas Haungs 10

11 KASCADE-Grande Accuracies with subsample of common events KASCADE + Grande Direction accuracy = 0.6 o shower size accuracy = 13% Core accuracy = 5m KASCADE-Grande coll., NIM A (2010) doi: /j.nima /6-2/7/2010, Nantes, France Andreas Haungs 11

12 Reconstruction of the energy spectrum size spectra (charged particles) muon number spectra (N µ ; E µ >230MeV) -stable data taking since 2004, c days effective DAQ time -performance of reconstruction (and detector) is stable 29/6-2/7/2010, Nantes, France Andreas Haungs 12

13 All-particle energy spectrum : via shower size (N ch ) Shower size spectrum QGSJET II hadronic interaction model Shower size attenuation corrected to fixed angle -Good reconstruction accuracy - Application of a response matrix to correct bin-to-bin fluctuations -Very composition dependent (need assumption of primary type) Energy spectrum (composition assumption) KASCADE-Grande collaboration, (D.Kang), ICRC 09 29/6-2/7/2010, Nantes, France Andreas Haungs 13

14 All particle energy spectrum : via muon number (N µ ) QGSJET II hadronic interaction model Muon size spectrum attenuation corrected to fixed angle -Less good reconstruction accuracy - Application of a response matrix to correct bin-to-bin fluctuations -Less composition dependence Energy spectrum (composition assumption) KASCADE-Grande collaboration (J.C.Arteaga-Velazquez), ICRC 09 29/6-2/7/2010, Nantes, France Andreas Haungs 14

15 All-particle energy spectrum : via combination of N µ and N ch log 10 (E) = [a p + (a Fe -a p ) k] log 10 (N ch ) + b p +(b Fe -b p ) k k = (log 10 (N ch /N µ ) - log10(n ch /N µ ) p ) / (log10(n ch /N µ ) Fe - log10(n ch /N µ ) p ) QGSJET II hadronic interaction model QGSJET II -different zenith angle bins -no composition dependence KASCADE-Grande collaboration (M.Bertaina), ICRC 09 29/6-2/7/2010, Nantes, France Andreas Haungs 15

16 The all-particle energy spectrum QGSJET II/FLUKA QGSJET II hadronic interaction model - very good agreement between results of different methods 29/6-2/7/2010, Nantes, France Andreas Haungs 16

17 The all-particle energy spectrum N ch -N µ method ~10% systematic uncertainty in flux QGSJET II hadronic interaction model - spectrum not describable by a single power law at ev 29/6-2/7/2010, Nantes, France Andreas Haungs 17

18 Ways to elemental composition : Application of different methods: - Local muon densities - High-energy muon investigations - Combination of N ch, N µ (e.g., fit of N µ /N e -ratios in fixed size/ energy bins) - Unfolding of the 2-dimensional shower size spectrum c.5600 events > ev Work in progress! 29/6-2/7/2010, Nantes, France Andreas Haungs 18

19 Way to elemental composition : muon density investigations - muon (local) density reconstruction for different, but fixed distances composition sensitive model dependence: heavy for QGSJet, light for EPOS slope of LDF okay for EPOS 1.99 KASCADE-Grande collaboration (V. de Souza), ICRC 09 29/6-2/7/2010, Nantes, France Andreas Haungs 19

20 Way to elemental composition : N µ / N e -ratio QGSJET II hadronic interaction model 6.5 < log 10 (N e ) < < log 10 (N e ) < shower size ratio: investigation of mean and rms rms of simulated distributions less model dependent than mean composition: more than 2 components needed; consistent with KASCADE in overlapping range KASCADE-Grande collaboration (E. Cantoni), ICRC 09 29/6-2/7/2010, Nantes, France Andreas Haungs 20

21 29/6-2/7/2010, Nantes, France Andreas Haungs 21

22 Implications A.M.Hillas, J. Phys. G: Nucl. Part. Phys. 31 (2005) R95 V.Berezinsky, astro-ph/ KASCADE-Grande: spectrum concave at ev small structure at ev mixed composition pure rigidity model unlikely at <10 18 ev eg-protons only unlikely 29/6-2/7/2010, Nantes, France Andreas Haungs 22

23 KASCADE-Grande 29/6-2/7/2010, Nantes, France Andreas Haungs 23

24 KASCADE-Grande GRAPES / AS /GAMMA ICETOP / ICECUBE TUNKA Yakutsk TA / TALE AMIGA/HEAT/AERA AUGER 29/6-2/7/2010, Nantes, France Andreas Haungs 24

25 30 March 2009 official closure ceremony KASCADE-Grande EAS Test Facility for internal and external users! e.g. LOPES! or HiSPARC 29/6-2/7/2010, Nantes, France Andreas Haungs 25

26 Connection particle array radio array: Radio detection technique is still in developing phase hardware, software, analysis, emission mechanism(s?), Calibration (understanding) radio emission Dependencies of radio signal Understanding emission mechanism(s) Capability of the radio detection technique? Sensitivity and resolution to primary energy? arrival direction? composition? EAS radio detection for CR (and neutrino) measurements: stand alone or hybrid technique? Comparing with particle arrays, not fluorescence technique (duty cycle). 29/6-2/7/2010, Nantes, France Andreas Haungs 26

27 Primary Energy LOPES Radio-Emission seems coherent! Energy sensitivity via electric field strength Radio signal (electric field) scales with primary energy: E 0 1 Power of electric field scales approximately quadratically with primary energy! - Sensitivity and resolution E/E ~ 20-25% - Particle array: 10-20% is energy resolution really worse? Model dependence? Emission mechanism? Geometry of shower? 29/6-2/7/2010, Nantes, France Andreas Haungs 27

28 Arrival Direction sensitivity via pulse arrival time and phase systematic studies of direction resolution: KASCADE vs. LOPES: offset (1.3±0.8) o resolution better 1 o (by beam forming; Better with increasing field strength, but number of antennas?) Artificial uncertainty introduced on each antenna ~1ns time resolution needed reduction of reconstructed signal strength F.Schröder et al., NIM A (2010) - Sensitivity and resolution (direction) << 1 o 29/6-2/7/2010, Nantes, France Andreas Haungs 28

29 Composition Lateral distributions seems to have composition sensitivity! model dependence? - Sensitivity and resolution?? - Particle array: unknown (large) uncertainty (FD better) by lateral sensitivity (pattern) by longitudinal sensitivity pulse shape wave front frequency spectrum. = Xmax (shower maximum) sensitivity needed!! 29/6-2/7/2010, Nantes, France Andreas Haungs 29

30 It works, but still many questions open: EAS Radio detection Radio signal (electric field) scales with primary energy: E 0 ( ~ 1) Radio signal scales with geomagnetic field: v x B (may be not all) Radio signal scales with core distance: exp (-R/R 0 ) (R 0 ~ m) Frequency spectrum is a decreasing power law (or exp) ( ~ -1) Radio signal is polarized (azimuth and observer position) dependent understanding of the radio emission and all its correlation with EAS parameters still important! suitable for hybrid measurements! 29/6-2/7/2010, Nantes, France Andreas Haungs 30

31 LOPES 10 Analysis : Distant Events Interplay of radio and shower particle analysis Grande Event: = o = o = o X c = m Y c = m lg(e/ev) = ln(a) = 3.16 curvature = 3250 m Weak coherence! 29/6-2/7/2010, Nantes, France Andreas Haungs 31

32 LOPES 10 Analysis : Distant Events Interplay of radio and shower particle analysis search for Event: maximum coherence = o = o = o = o = o X c = m = m Y c = m = m lg(e/ev) = ln(a) = 3.16 curvature = 3250 m = 4250 m Weak coherence! Coherence! 29/6-2/7/2010, Nantes, France Andreas Haungs 32

33 LOPES 10 Analysis : Distant Events Interplay of radio and shower particle analysis search for Event: maximum coherence = o = o = o = o = o X c = m = m Y c = m = m lg(e/ev) = ln(a) = 3.16 curvature = 3250 m = 4250 m Weak coherence! Coherence! Improvement of shower core and arrival direction estimate in Grande by LOPES! 29/6-2/7/2010, Nantes, France Andreas Haungs 33

34 Lesson to be learned: be careful that you are not fooled by sensors! 29/6-2/7/2010, Nantes, France Andreas Haungs 34

35 Lesson to be learned: be careful that you are not fooled by sensors! 29/6-2/7/2010, Nantes, France Andreas Haungs 35

36 Summary / Status high quality data at ev by KASCADE-Grande to identify the iron - knee and transition galactic extragalactic cosmic rays! first results KASCADE-Grande: energy spectrum : no single power law (concave form at ev) elemental composition more than two components needed around ev anisotropy studies no anisotropy seen interaction models muon attenuation, muon production height, etc 30/03/2009: KASCADE-Grande closure symposium KASCADE-Grande EAS test facility data analysis continued new detection techniques: LOPES radio detection of air showers sensitivities of radio (hybrid performance!) 29/6-2/7/2010, Nantes, France Andreas Haungs 36