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Announcement of UHECR symposium in Nagoya, Japan. 10-12 December Visit http://uhecr2010.icrr.u-tokyo.ac.jp/ for detail 15-Oct ; abstract deadline Mainly invited talks and contribution posters Some contributions may be selected for oral presentations 12-Nov; registration deadline
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Announcement of UHECR symposium in Nagoya, Japan • 10-12 December • Visit http://uhecr2010.icrr.u-tokyo.ac.jp/ for detail • 15-Oct ; abstract deadline • Mainly invited talks and contribution posters • Some contributions may be selected for oral presentations • 12-Nov; registration deadline • Contents • Highlights from PAO, HiRes, TA and future plan • Accelerator results; AirFly, TA ELS, LHCf • Acceleration, Propagation, Multi messenger astrophysics • Panel discussions on technique, UHECR origin, interaction
First Results of LHCf; Very Forward Particles at LHC Collision Takashi SAKO (Solar-Terrestrial Environment Laboratory, Nagoya University, Japan) for the LHCf Collaboration ICATPP Conference, Villa Olmo,Como, Italy, 7-8 October 2010
UHECR and Hadron Interaction • Recent excellent observations by PAO, HiRes and TA, but still puzzling in the UHECR origin • Uncertainty in hadron interaction affects in • Prediction of Xmax • SD observations • Cross sections of very forward particle emission at as high as possible energy is indispensible => LHC forward (LHCf) experiment
The LHCf Collaboration K.Fukatsu, Y.Itow, K.Kawade, T.Mase, K.Masuda, Y.Matsubara, G.Mitsuka, K.Noda, T.Sako, K.Suzuki, K.Taki Solar-Terrestrial Environment Laboratory, Nagoya University, Japan K.Yoshida Shibaura Institute of Technology, Japan K.Kasahara, M.Nakai, Y.Shimizu, T.Suzuki, S.Torii Waseda University, Japan T.Tamura Kanagawa University, Japan Y.Muraki Konan University M.Haguenauer Ecole Polytechnique, France W.C.Turner LBNL, Berkeley, USA O.Adriani, L.Bonechi, M.Bongi, R.D’Alessandro, M.Grandi, H.Menjo, P.Papini, S.Ricciarini, G.Castellini INFN, Univ. di Firenze, Italy A.Tricomi INFN, Univ. di Catania, Italy J.Velasco, A.Faus IFIC, Centro Mixto CSIC-UVEG, Spain D.Macina, A-L.Perrot CERN, Switzerland
ATLAS 96mm Experimental Set-up LHCf Detector(Arm#1) 140m LHCf Detector (Arm#2) Protons Charged particles(+) Neutral particles Beam pipe Charged particles(-) √s=14TeV proton collision = 1017eV in the lab. frame
Arm#1 Detector 20mmx20mm+40mmx40mm 4 XY SciFi+MAPMT Arm#2 Detector 25mmx25mm+32mmx32mm 4 XY Silicon strip detectors LHCfDetectors *Imaging sampling shower calorimeters *Two independent calorimeters in each detector(Tangsten 44r.l., 1.7λ, sample with plastic scintillators)
Expected Results at 14 TeV Collisions(assuming 0.1nb-1 statistics) Detector response not considered
Summary of Operations in 2009 and 2010 • With Stable Beam at 900 GeV • Total of 42 hours for physics • About105 showers events in Arm1+Arm2 • With Stable Beam at 7 TeV • Total of 150 hours for physics with different setups • Different vertical position to increase the accessible kinematical range • Runs with or without beam crossing angle • ~ 4·108 shower events in Arm1+Arm2 • ~ 106p0 events in Arm1+Arm2 • Status • Completed program for 900 GeV and 7 TeV • Removed detectors from tunnel in July 2010 • Post-calibration beam test in October 2010 • Upgrade to more rad-hard detectors to operate at 14TeV in 2013
TeV Gamma not from Crab but Underground! ! Event sample measured by Arm2 at 30 March 2010
Particle Identification A transition curve for Gamma-ray A transition curve for Hadron Thin for hadronic interaction(1.7l) Thick for E.M.interaction (44X0) L90% @ 40mm cal. of Arm1 Definitionof L90% MC (QGSJET2) Preliminary Data Gamma-ray like Hadron like • L90%; longitudinal position containing 90% of the sum of the shower particles. • PID bias, Neural Net are in investigation Criteria for gamma-rays 16 r.l. + 0.002 x SdE
Energy Spectra at 900GeV Hadron response under study Arm1 Hadron like Gamma-ray like preliminary preliminary Only statistical errors are shown Arm2 Hadron like Gamma-ray like preliminary preliminary Acceptance is different in two arms Normalized by number events Response for hadrons and systematic error are under study.
Arm1 Gamma-ray like Hadron like preliminary preliminary Arm2 Gamma-ray like Hadron like preliminary preliminary Measured Spectra at 7TeV Very high statistics !! only 2% of all data Comparisons with MC will be available soon Careful study of systematic error is ongoing
Neutral Pions An example ofevent (Arm2) Energy spectrum (Arm2) 25mm 32mm preliminary Silicon strip-X view 1(E1) Reconstructed mass (Arm2) R 140m ΔM/M=2.3% M/M=2.3% 2(E2) I.P.1 preliminary preliminary • Pi0’s are a main source of electromagnetic secondaries in high energy collisions. • The mass peak is very useful to confirm the detector performances and to estimate the systematic error of energy scale.
14TeV in 2013; Not only highest energy, but energy dependence… SIBYLL QGSJET2 Note: detector aperture taken into account (biased) 7 TeV 10 TeV 14 TeV(1017eV@lab.) 7 TeV 10 TeV 14 TeV Secondary gamma-ray spectra in p-p collisions at different collision energies (normalized to the maximum energy) SIBYLL predicts perfect scaling while QGSJET2 predicts softening at higher energy Qualitatively consistent with Xmax prediction
Summary • LHCf has successfully completed operation at 900GeV and 7TeV collisions at LHC • Unprecedented quality of data allows to test existing hadron interaction models and helps to construct new models • Operation at 14TeV collisions in 2013 will set more strict limits on the hadron interaction models to extrapolate into higher energy Analysis of the first result will be finalized soon
Announcement of UHECR symposium in Nagoya, Japan • 10-12 December • Visit http://uhecr2010.icrr.u-tokyo.ac.jp/ for detail • 15-Oct ; abstract deadline • Mainly invited talks and contribution posters • Some contributions may be selected for oral presentation • 12-Nov; registration deadline • Contents • Highlights from PAO, HiRes, TA and future plan • Accelerator results; AirFly, TA ELS, LHCf • Acceleration, Propagation, Multi messenger astrophysics • Panel discussions on technique, UHECR origin, interaction
Open Issues on HECR spectrum AGASA Systematics Total ±18% Hadr Model ~10% (Takeda et al., 2003) M Nagano New Journal of Physics 11 (2009) 065012 Depth of the max of the shower Xmax in the atmosphere AUGER HiRes
Arm1 η Shadow of beam pipes between IP and TAN 8.7 ∞ neutral beam axis IP1,ATLAS Arm2 8.4 ∞ @ 140mrad crossing angle Transverse projection of Arm#1 @ zero crossing angle
Pseudo-rapidity Coverage ATLAS Energy spectra and Transverse momentum distribution of • Gamma-rays (E>100GeV,dE/E<5%) • Neutral Hadrons (E>a few 100 GeV, dE/E~30%) • Neutral Pions (E>700GeV, dE/E<3%) LHCf at psudo-rapidity range >8.4 Multiplicity@14TeV Energy Flux @14TeV High energy flux !! Low multiplicity !! simulated by DPMJET3
Eγ – PTγCorrelation plot 140 Beam crossing angle Detectable events
h search p0Candidate h Candidate preliminary • h/p0ratio vary a lot among different interaction models. • A good handle to probe the hadron interaction models • Another calibration point for more robust energy scale
Detector p,e-,mu Beam test at SPS Energy Resolution for electrons with 20mm cal. • - Electrons 50GeV/c – 200GeV/c • Muons 150GeV/c • Protons 150GeV/c, 350GeV/c Position Resolution (Silicon) Position Resolution (Scifi) σ=172μm for 200GeV electrons σ=40μm for 200GeV electrons
Accumulated Events in 2010 108 events! LHCf removal