LHCF; CONNECTING COLLIDER TO

ASTROPARTICLE PHYSICS

Takashi Sako (STE lab/KMI, Nagoya University)for the LHCf collaboration

HEAP 2011, 13-15 Nov. 2011, KEK1

2

Uncertainty in hadronic interaction

PROTON

IRON

10191018

0g/cm2

Xmax

Proton shower and nuclear shower of same total energy

Pierre Auger Observatory (PAO)

Deep in the atmosphere

3

Uncertainty in hadronic interaction

PROTON

IRON

10191018

0g/cm2

Xmax

Proton shower and nuclear shower of same total energy

Pierre Auger Observatory (PAO)

Deep in the atmosphere

Constraints from accelerator experiments indispensible

What should be measured at collidersmultiplicity and energy flux at LHC 14TeV collisions

pseudo-rapidity; η= -ln(tan(θ/2))

Multiplicity Energy Flux

All particles

neutral

Most of the energy flows into very forward4

The LHC forward experiment

5

96mm

ATLAS

140m

LHCf Detector(Arm#1)

Two independent detectors at either side of IP1 ( Arm#1, Arm#2 )

Charged particles (+)Beam

Charged particles (-)

Neutral particles

LHCf Detector(Arm#2)

Beam pipe

√s=14TeV

Elab=1017eV

K.Fukatsu, T.Iso, Y.Itow, K.Kawade, T.Mase, K.Masuda, Y.Matsubara, G.Mitsuka, Y.Muraki, T.Sako, K.Suzuki, K.Taki Solar-Terrestrial Environment Laboratory, Nagoya University, Japan

H.Menjo Kobayashi-Maskawa Institute, Nagoya University, Japan

K.Yoshida Shibaura Institute of Technology, Japan

K.Kasahara, Y.Shimizu, T.Suzuki, S.Torii Waseda University, Japan

T.Tamura Kanagawa University, Japan

M.Haguenauer Ecole Polytechnique, France

W.C.Turner LBNL, Berkeley, USA

O.Adriani, L.Bonechi, M.Bongi, R.D’Alessandro, M.Grandi, P.Papini, S.Ricciarini, G.Castellini INFN, Univ. di Firenze, Italy

K.Noda, A.Tricomi INFN, Univ. di Catania, Italy

J.Velasco, A.Faus IFIC, Centro Mixto CSIC-UVEG, Spain

A-L.Perrot CERN, Switzerland

The LHCf Collaboration

6

LHCf Detectors

Arm#1 Detector20mmx20mm+40mmx40mm4 XY SciFi+MAPMT

Arm#2 Detector25mmx25mm+32mmx32mm4 XY Silicon strip detectors

Imaging sampling shower calorimeters Two independent calorimeters in each detector (Tungsten 44r.l.,

1.6λ, sample with plastic scintillators)

7

8

9

Event category of LHCf

10

π0 photonPi-zero event(photon pair)

Single photon event

Leading baryon(neutron)

Multi meson production

Single hadron event

LHCf calorimeters

π0 photon

Expected Results at 14 TeV Collisions(MC assuming 0.1nb-1 statistics)

Detector response not considered

Operation 2009-2010　With Stable Beam at √s = 900 GeV

Total of 42 hours for physics About 105 shower events in Arm1+Arm2

With Stable Beam at √s = 7 TeV (Elab = 2.5x1016 eV) 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

~ 4x108 shower events in Arm1+Arm2 ~ 106 π0 events in Arm1 and 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 for 14TeV in 2014

12

TeV Gamma not only from Crab but Underground!

Event sample measured by Arm2 at 30 March 2010

!

Energy Determination

Position Determination

Longitudinal development

Lateral development

Silicon X

Silicon Y

Particle Identification PID (EM shower selection)

– Select events <L90% threshold and multiply P/ε ε (photon detection efficiency) and P (photon purity)

– By normalizing MC template L90% to data, ε and P for certain L90% threshold are determined.

14

EM hadron

hadron

EM

EM

L90%L90%

Photon spectra at √s=7TeV collisions

(Adriani et al., PLB, 2011)

Spectra of Arm1&2 at common η σine = 71.5mb assumed; consistent with the other LHC

experiments

15

zero degree

16

Comparison with Models

DPMJET 3.04 QGSJET II-03 SIBYLL 2.1 EPOS 1.99 PYTHIA 8.145

Adriani et al., PLB, 2011

π0 identification• A Pi0 candidate event• 599GeV & 419GeV photons in 25mm

and 32mm tower, respectively• M = θ√(E1xE2)

17

Event sample in Arm2

Longitudinal development

Lateral development

Silicon X

Silicon Y

Small Cal.

LargeCal.

m 140=

R

I.P.1

1(E1)

2(E2)

140mR

Invariant mass of photon pairsComparison with models, in progress

π0 Analysis more…

18

OriginalIdea

New Analysis!

π0 spectrum and air shower

Artificial modification of meson spectra and its effect to air shower

Importance of E/E0>0.1 mesons Playing at LHC energy within

reasonable modification range19

π0 spectrum at Elab = 1019eV

QGSJET II originalArtificial modification

Longitudinal AS development

Ignoring X>0.1 meson

X=E/E0

30g/cm2

900GeV Analysis(Next target to publication)

20

Entry normalization No PID bias correction Ongoing works

• Luminosity normalization• PID correction• Systematics study• Increasing MC statistics , etc…

Preliminary

Preliminary

100 200 300 400 500Energy (GeV) 100 200 300 400 500Energy (GeV)

102

102

DataDPMJET 3.04QGSJET II-03SIBYLL 2.1PYTHIA 8.146EPOS 1.99

Experimental Plan

14TeV p-p collisions (Elab=1.0x1017eV)• Assured in 2014

LHC p-Pb collisions• In discussion for 2012

RHIC 500GeV p-p collisions• Starting discussion

LHC/RHIC (p,C,Fe)-CNO collisions

21

Experimental Plan

14TeV p-p collisions (Elab=1.0x1017eV)• Assured in 2014 --- highest energy

LHC p-Pb collisions• In discussion for 2012

RHIC 500GeV p-p collisions• Starting discussion

LHC/RHIC (p,C,Fe)-CNO collisions

22

Experimental Plan

14TeV p-p collisions (Elab=1.0x1017eV)• Assured in 2014 --- highest energy

LHC p-Pb collisions• In discussion for 2012 --- nuclear effect

RHIC 500GeV p-p collisions• Starting discussion

LHC/RHIC (p,C,Fe)-CNO collisions

23

Experimental Plan

14TeV p-p collisions (Elab=1.0x1017eV)• Assured in 2014 --- highest energy

LHC p-Pb collisions• In discussion for 2012 --- nuclear effect

RHIC 500GeV p-p collisions• Starting discussion --- energy dependence

LHC/RHIC (p,C,Fe)-CNO collisions

24

Experimental Plan

14TeV p-p collisions (Elab=1.0x1017eV)• Assured in 2014 --- highest energy

LHC p-Pb collisions• In discussion for 2012 --- nuclear effect

RHIC 500GeV p-p collisions• Starting discussion --- energy dependence

LHC/RHIC (p,C,Fe)-CNO collisions• Dream! Before my retirement…

25

Related to CTA???

Related to CTA???

27

0°

5°

10°20°

Proton : E-2 (<512TeV)Beam (3° FWHM)

Karlsson and Kamae, ApJ 674, 278-285 (2008)

Summary

LHCf successfully took data at LHC 0.9 and 7TeV p-p collisions

First analysis results for photon spectraNone of the models can fit the data, but the

data is within model diversity Further analysis on going Variety of future experiments are

assured and in discussion Possible relation to CTA physics?

28

Backup

29

30

31

32

33

Leading baryons

Multi meson production

(High energy) (Low energy)

Secondary inHadron Interaction

proton / neutron

π0 π+ π-

γ

EM shower

Next interaction

μ

34

Leading baryons

Multi meson production

(High energy) (Low energy)

LHCf can measure

proton / neutron

π0 π+ π-

γ

EM shower

Next interaction

μ

Key measurements in colliders

E leading baryon

Elasticity / inelasticity Meson MultiplicityTotal cross section(TOTEM at LHC)

EM shower

E0

Forward spectra

Air shower experimentsAstrophysical parameters - source type - source distribution - source spectrum - source composition - propagation

Observations - lateral distribution - longitudinal distribution - particle type - arrival timing

Primary CR - energy - chemical composition - direction

Air shower experimentsAstrophysical parameters - source type - source distribution - source spectrum - source composition - propagation

Observations - lateral distribution - longitudinal distribution - particle type - arrival timing

Primary CR - energy - chemical composition - direction

Air shower development - interaction - atmosphere