Review of accelerator data of relevance to air shower simulations

Transcription

1 Y.Itow, Review of Accelerator data 14Feb2012 Review of accelerator data of relevance to air shower simulations Yoshitaka Itow STE Lab / Kobayashi-Maskawa Inst. Nagoya University UHECR 2012 Feb 13-16, 2012, CERN 1

2 Hadron interactions at ultra high energy Accelerator Cosmic rays Precision improvement Hint for interactions at ultra-ultra high energy E CM ~ ( 2 E lab M p ) 1/2 s=14tev collision at LHC ev cosmic rays 2

3 Cosmic ray spectrum & historical colliders TALE HEAT AUGER, TA ev ISR RHIC SppS LHC 0.9TeV Tevatron LHC 7 TeV LHC 14TeV >40 yrs legacy of wisdom for interactions available! 3

4 Inelastic cross section 2ndary interactions nucleon, π If large σ rapid development If small σ deep penetrating Forward energy spectrum If softer shallow development If harder deep penetrating Inelasticity k= 1-p lead /p beam Important, but irrelevant to A.S. P T multiplicity (relevant to N µ ) If large k rapid development If small k deep penetrating 4

5 Outline of this talk What type of interactions we concern? Sort out the data regarding as relevance to air showers phenomena, especially focusing on Xmax Inelastic cross section Forward energy spectra Inelasticity low energy data Nuclear effect is important, but This talk focuses just on p-p Comments on possible p-a runs at LHC before long shutdown 5

6 IP5 :CMS TOTEM The 7 LHC experiments IP2: ALICE Beam 1 Beam 2 IP1 : ATLAS LHCf IP8: LHCb, MoEDAL 6

7 A LHC detector and pseudorapidity Central detector (ATLAS) (pseudo)rapidity η = θ ln(tan ) 2 IP ZDC (η>~8.5) LHC tunnel 7

8 pseudorapidity and interactions Elastic φ -10 η -10 ~25mb Single diffractive Double diffractive φ φ -10 η -10 η gap -10 η -10 ~10mb ~10mb Nondiffractive φ -10 η -10 ~50mb 8

9 Very forward : Majority of energy flow ( s=14tev) Multiplicity Energy Flux All particles neutral 8.4 < η < Most of the energy flows into very forward ( Particles of X F > 0.1 contribute 50% of shower particles ) 9

10 Energy flow for s=14 and 7TeV 14TeV LHCf/ZDC 7TeV CMS HF CMS HF ATLAS/CMS LHCf/ZDC Double diffractive π 0 Single diffractive π 0 10

11 Inelastic cross section TOTEM ATLAS CMS ALICE 11

12 Measurement of σ inel Total inelastic rate : R inel Total rate: R tot : N proj : N targ Total elastic rate: R el σ σ projectile target Optical theorem tot tot = ρ R el L = Rtot = Rel + frevn L = πσ VdM scan 16π + R R proj inel N Σ 2 proj t arg inel t arg dr dt el t= 0 Simple way drel dt R L t=0 ρ = Re Im R inel σ inel =, inel = t = Elastic rate at 0 degree ( fel ( 0) ) ( f ( 0) ) el ( p in pout R ε 2 ) obs eff 12

13 σ inel ( ξ > ) = ATLAS σ inela measurement Nature Commun. 2 (2011) 463 N ε obs trig N BG Ldt 1 f ξ < 5 10 ε sel 6 Minimum Bias Trigger Scintillator(MBTS) Use MB events with µb -1 Cut diffractive events ( ξ < 5E-6) σ inel ( ξ > ± 2.10(exp.) mb σ inel ( ξ > 2 m p 69.1± 2.4(exp.) ± 6.9( extr) mb ) / s) = = extrapolate entire ξ 13

14 TOTEM Roman Pod measurement 14 m Roman Pot stations in the LHC tunnel ( F.Ferro, Diffraction 2010) RP (147 m) RP (220m) 14

15 dσ dt el = mb/gev 2 t=0 Roman pod measurement σ 2 tot TOTEM σ inel EPL, 95 (2011) π ( c) = 2 1+ ρ 2 dr dt ρ = (COMPETE collaboration) el t= 0 dσ el dt t=0 σ tot = 98.3 ± mb Integrated over entire t region d σ el el = σ dt = 24.8 ± 0.2 ± 1. 2mb dt σ = inel 73.5 = σ σ ± tot el mb 15

16 σ inel 7TeV UA4 Tevatron LHC ISR TOTEM mb dσ/dt(t=0) ATLAS ,9 mb MBTS sample CMS mb Ntrk sample ALICE mb VZERO sample 16

17 ALICE σ diffraction J. Phys. G: Nucl. Part. Phys. 38 (2011)

18 Forward energy spectra / Inelastiscity / P T LHCf UA7 CMS FCAL RHIC BRAHMS Forward neutron spectra 18

19 LHC zero degree experimental site Protons Charged particles (+) 96mm Neutral particles Beam pipe Charged particles (-) 140m ATLAS LHCf/ZDC 140m TAN absorber 19

20 LHCf: location and detector layout Detector I Tungsten Scintillator Scintillating fibers INTERACTION POINT IP1 (ATLAS) Detector II Tungsten Scintillator Silicon µstrips Front Counter Front Counter 140 m 140 m 8 cm 6 cm n 0 44X 0, 1.6 λ int Arm#1 Detector 20mmx20mm+40mmx40mm 4 SciFi tracking layers Arm#2 Detector 25mmx25mm+32mmx32mm 4 Silicon strip tracking layers 20

21 Rapidity vs Forward energy spectra η=5.99 η=6.91 η=7.60 η=8.40 η=8.77 η=5.99 η=6.91 η=7.60 η=8.40 η=8.77 [ rad] Viewed from IP1 (red:arm1, blue:arm2) Projected edge of beam pipe 21

22 LHCf single γ spectra at 7TeV DPMJET 3.04 QGSJETII-03 SIBYLL 2.1 EPOS 1.99 PYTHIA Phys.Lett. B703 (2011) Gray hatch : Systematic Errors Blue hatch: Statistics errors of MC 22

23 New LHCf single γ spectra at 900 GeV ( to be submitted PLB) 23

24 LHCf 900GeV single γ spectra: Data/MC 900GeV 24

25 LHCf 900GeV single γ spectra: Data/MC High η low η 900GeV 7TeV 25

26 UA7 π 0 P T Phys.Lett. B242 (1990) at 630GeV γ p p UA7 630GeV dσ/dy (mb) P T ( MeV/c) Y 26

27 New LHCf π 0 P T at 7TeV ( Preliminary ) 27

28 CMS HF : forward energy flow CMS HF LHCf/ZDC ATLAS/CMS 28

29 CMS HF: Forward energy flow CERN-PH-EP/ , arxiv/ TeV 7TeV 3.15< η <

30 RHIC BRAHMS : charged spectra at s=200gev PRL 98, (2007) 30

31 Inelasticity~ 0 degree neutron spectra Important for X max and also N µ Measurement of inelasticity at LHC energy Neutral hadrons at 14 TeV (LHCf acceptance, no resolution) Neutral hadrons at 14 TeV (LHCf acceptance, 30% resolution) 31

32 Future data for forward energy flow Forward neutrons by LHC ZDC s So far working well for centrality in HI runs Potentially they can work nicely (PID?) Combined LHCf+ATLAS ZDC may benefit Other LHC forward detectors CMS CASTOR :Only coverage for η ~ 6 TOTEM T1, T2, LHCb VELO( 1.6<η< 4.9? ) New LHC detectors? CMS Forward Shower Calorimeter (FSC)? Roman Pod type calorimeter (a la UA7)? RHIC 0dgree measurement? RHIC IP s= 500GeV with larger P T acceptance Possible π 0 measurement 32

33 Summary : forward spectra coverage η ATLAS CMS ALICE dn/dη BRAHMS PT CMS HF UA7 π 0 LHCf 7TeV π 0 LHCf 0.9TeV γ LHCf 7TeV γ θ =<P T >/ P beam <P T >~0.4GeV/c ISR dn/dη UA5 dn/dη CDF dn/dη s 33

34 Low energy data Exp beam target NA49 CERN SPS 128GeV/c p C, p NA61 CERN SPS 31GeV/c p, etc π+- HARP CERN PS 3,5,8,9,12GeV/c p π+- C, Be C,Be,p.. NA61 p beam = 31GeV/c MIPP FNAL-MI 58,120GeV/c p C,Be Relevant E (10 15 ev shower) P lab =10~10 3 GeV HARP p+c π +X p beam = 12GeV/c 34

35 Available accelerator data summary 35

36 Available accelerator data summary HARP NA61 MIPP NA49 36

37 Summary Synergy btw UHECR and LHC is so important to solve UHECR problems and to explore ultra high E interactions at beyond-lhc. Key parameters for understanding air showers, σ inel, forward spectra, inelasticity, multiplicity, P T should be measured in various energy ranges. First TOTEM σ inel LHCf forward spectra Recent progress in various energy range (i.e. NA61, HARP, etc.) Striking impacts on UHECR analysis has been given by recent LHC data as well as legacy data by various accelerator experiments. Stay tuned. Nuclear effects (QGP, shadowing, etc.) not address here are also important. LHC A-A, p-a run will be able to address it. 37

38 p+c π X data NA49 ( p beam =158GeV/c ) NA61 ( p beam =31GeV/c ) NA61(SHINE) p beam data sets NA61 p beam = 31GeV/c NA49 p beam = 158GeV/c 38

39 HARP / MIPP MIPP detector 39

40 Available accelerator data summary 40

41 41

42 Parent particles relevant for LHCf observations Sybill at 7TeV 42

43 43

44 Inelasticity 44

45 LHCf forward spectra: Data/MC High η low η 45

46 LHCf forward spectra: Data/MC High η low η 46

47 Elasticity ( X F of leading baryon) 47

48 p+p p+x at P beam = 205GeV (FNAL bubble chamber) FNAL bubble chamber p + p p + X (at 205GeV/c) Whitmore et al, PRD11(1975)

49 UA7 vs. PYTHIA8 Pare et al. PYTHIA8 (histos) vs UA7 fit PYTHIA8 does not reproduce UA7 Can we confirm/update/improve UA7? 49

50 LHCf forward spectra: Data/MC High η low η 50

51 Setup in IP1-TAN (side view) BRAN-Sci ZDC type1 BRAN-IC ZDC LHCf type2 Calorimeter LHCf Front Counter Side view Beam pipe TAN Neutral particles IP1 51

52 Forward E spectra forseen at 14TeV (MC for ~0.1nb -1 ) single γ Neutrons (true energy) π 0 Neutrons (w/ 30% resolution) 52

53 The single photon energy spectra at 0 degree DATA 15 May :45 21:23, at Low Luminosity 6x10 28 cm 2 s 1, no beam crossing angle 0.68 nb 1 for Arm1, 0.53nb 1 for Arm2 MC DPMJET3.0, QGSJETII03, SYBILL2.1, EPOS1.99 PYTHIA with the default parameters inelastic p-p collisions by each model. Analysis Two pseudo-rapidity, >10.94 and 8.81< <8.9. No correction for geometrical acceptance. Combine spectra between Arm1 and Arm2. Normalized by number of inelastic collisions with assumption as σ inela = 71.5mb. (c.f mb by TOTEM ) -1.3 (O.Adriani et al., PLB703 (2011) Arm1 Arm2 53

54 Particle Identification Event selection and correction Select events <L 90% threshold and multiply P/ Calorimeter Depth (photon detection efficiency) and P (photon purity) By normalizing MC template L 90% to data, and P for certain L 90% threshold are determined. Elemag: 44r.l. Hadronic: 1.7 L 90% Distribution de Photon Hadron Calorimeter layers Integral of de Calorimeter layers 54

55 Very forward connection to low-x physics Low-x high-x Very forward Very forward region : collision of a low-x parton with a large-x parton Small-x gluon become dominating in higher energy collision by self interaction. But they may be saturated (Color Glass Condenstation) Naively CGC-like suppression may occur in very forward at high energy However situation is more complex (not simple hard parton collsions, but including soft + semi-hard ) soft hard semihard 55

56 What P T range LHCf sees? γ π 0 pp 7TeV, EPOS 56

57 RHIC: 0 at s =500GeV ZDC space at PHENIX (by Goto san): 10cm radius beam pipe aperture at 18m => >

58 Pi0 in 500GeV p-p collisions by PYTHIA8 Multiplicity Energy Flux All particles neutral Eta vs. Energy Eta vs. number flux Eta vs. energy flux Vertical lines at =6 58

59 Comparison between the two detector Pseudo-rapidity selection, >10.94 and 8.81< <8.9 Normalized by number of inelastic collisions with assumption as σ inela = 71.5mb ( <-> mb by TOTEM ) Spectra in the two detectors are consistent within errors Combined between spectra of Arm1 and Arm2 by weighted average according to errors Arm1 detector Arm2 detector 59

60 Forward production spectra vs Shower curve X F = E/Etot Half of shower particles comes from large X F γ Measurement at very forward region is needed 60

61 Transition curve for ev proton 0 reconstructed spectrum X max = 696.6g/cm , -7.8 g/cm 2 statistical systematic X max (DPMJET -QGSJET ) = 36g/cm 2 OSCAR ADRIANI LHCC MEETING, CERN 23 MARCH

62 62

63 Contribution from very forward production No cut ev proton showers ( 60 deg zenith) low X F γ origin ( x F < 0.05 ) π,κ origin ( x F < 0.1 ) # of electrons Half of shower particles comes from large X F γ Measurement at very forward region is needed 63

64 Forward energy spectra η=5.99 η=6.91 η=7.60 η=8.40 η=

65 Impact of parameters of interactions p p Cross section X max X max multiplicity elasticity Fe RMS X max Fe RMS X max R.Ulrich et al., PRD83(2011)

66 Big LHC detectors 66