New Developments of EPOS 2 Tanguy Pierog 1 , K. Werner 2 , Y. - - PowerPoint PPT Presentation

▶
new developments of epos 2
SMART_READER_LITE
LIVE PREVIEW

New Developments of EPOS 2 Tanguy Pierog 1 , K. Werner 2 , Y. - - PowerPoint PPT Presentation

May 28, 2023 315 likes •621 views

The EPOS model Preliminary results New developments New Developments of EPOS 2 Tanguy Pierog 1 , K. Werner 2 , Y. Karpenko 2 , S. Porteboeuf 2 1- Institut fr Kernphysik, Karlsruhe, Germany 2 - SUBATECH, Nantes, France XVI th ISVHECRI,

slide-1
SLIDE 1
  • T. Pierog, KIT - 1/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

Tanguy Pierog1,

  • K. Werner2, Y. Karpenko2, S. Porteboeuf2

1- Institut für Kernphysik, Karlsruhe, Germany 2 - SUBATECH, Nantes, France

XVIth ISVHECRI, Chicago, USA June the 30th 2010

New Developments of EPOS 2

slide-2
SLIDE 2
  • T. Pierog, KIT - 2/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

Outline

The EPOS model

Baryons and remnants

New developments

3D Hydrodynamical calculation New Parton Distribution Function (PDF) LHC data

Preliminary results

LHC Consequences on air shower development

slide-3
SLIDE 3
  • T. Pierog, KIT - 3/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

EPOS first designed to be used for particle physics experiment analysis (SPS, RHIC, LHC)

The EPOS Model

EPOS* is a parton model, with many binary parton-parton interactions, each one creating a parton ladder.

Energy-sharing : for cross section calculation AND particle production Parton Multiple scattering Outshell remnants Screening and shadowing via unitarization and splitting Collective effects for dense systems EPOS can be used for minimum bias hadronic interaction generation (h-p to A-B) from 100 GeV (lab) to 1000 TeV (cms) : used for air shower !

*T.Pierog, S. Porteboeuf and K. Werner

slide-4
SLIDE 4
  • T. Pierog, KIT - 4/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

Baryons and Remnants

Parton ladder string ends :

Problem of multi-strange baryons at low energy (Bleicher et al., Phys.Rev.Lett.88:202501,2002) 2 strings approach :

Ω / Ω always > 1 But data < 1 (Na49)

EPOS No “first string” with valence quarks : all strings equivalent Wide range of excited remnants (from light resonances to heavy quark-bag)

Ω / Ω always < 1

d s s s s u d u d s s d UUD s s u u D d s s u d s s u u D sss d U decay

(excited)

U U u u s U U

slide-5
SLIDE 5
  • T. Pierog, KIT - 5/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

New Developments (1)

Collective effects (hydro) needed for heavy ions

Important even for pp and pA

explain <pt> vs mult. (flow), strangeness, baryon pt shape, etc … replace former effective treatment needed to describe these data (medium dependent string parameters)

In EPOS 2 : detailed 3D hydro calculation

For CR same simplified calculation of collective effects as in EPOS 1.x but with flow extrapolation based on calculation instead of low energy data (large uncertainty).

EPOS approach : use theory to fix the framework and adapt the details to be as close as possible to all possible data.

slide-6
SLIDE 6
  • T. Pierog, KIT - 6/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

Hydro in EPOS 2

Features

Flux-tube initial condition Event-by-event treatment 3D core-corona procedure Tree flavor cross-over EoS (X3F) 3 + 1D hydro Complete hadron set (latest PDG) Hadronic cascade (HC), here UrQMD

Checks : Centrality dependence of

Yields and pt spectra of identified particles v2 and pt dependence of v2 of identified particles Particle correlations (eta-phi, HBT (in progress), ...)

slide-7
SLIDE 7
  • T. Pierog, KIT - 7/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

Check with Heavy Ions : AuAu@RHIC

Important role of core-corona effect (K. Werner et al. J.Phys.G36:064030,2009) Early freeze-out (166MeV) + hadr. cascade

Full casc. Elastic casc. Full casc. Elastic casc.

slide-8
SLIDE 8
  • T. Pierog, KIT - 8/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

First Real Hydro in ap-p@1.8 TeV : Radial Velocity

Apply same parameters as for AuAu@RHIC

(except flux tube radius = free parameter) τ=0.6 τ=1.0 τ=1.4 τ=2.5 τ=2.1 τ=1.7 2 50 50 60 70 60 22

  • 2

2

slide-9
SLIDE 9
  • T. Pierog, KIT - 9/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

<pt> vs multiplicity ap-p@1.8 TeV : EPOS 2

No collective effects hydro+hadronic cascade

Using small flux tube size

Very good description of CDF data No additional parameter Hadron mass dependence

λ

Ks Charged

slide-10
SLIDE 10
  • T. Pierog, KIT - 10/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

New Developments (2)

New fragmentation function based on initial parton type in jets (gluon or quark)

Natural change of baryon and strangeness production with energy

Needs for LHC

Proper PDF needed for hard scattering (Jet, etc …) In EPOS 2 : F2 data from HERA used in global fit (same parameters for cross-section,

PDF and multiplicity …)

Hard diffraction New parameters taken into account LHC data Preliminary results EPOS approach : use theory to fix the framework and adapt the details to be as close as possible to all possible data.

slide-11
SLIDE 11
  • T. Pierog, KIT - 11/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

Parton Distribution Function

PDF based and DGLAP and initial soft parametrization

Preliminary

slide-12
SLIDE 12
  • T. Pierog, KIT - 12/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

LHC data (1)

Higher average multiplicity due to reduced screening

Preliminary

slide-13
SLIDE 13
  • T. Pierog, KIT - 13/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

LHC data (1)

Higher average multiplicity due to reduced screening

Preliminary

slide-14
SLIDE 14
  • T. Pierog, KIT - 14/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

LHC data (2)

Multiplicity tale still not long enough Pt now to high ?

Only lack of low pt particles ? Preliminary

slide-15
SLIDE 15
  • T. Pierog, KIT - 15/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

Air Shower Development

Change in multiplicity seen in <Xmax>

~ 10 gr/cm2

slide-16
SLIDE 16
  • T. Pierog, KIT - 16/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

Summary

On-going developments : EPOS 2 Real hydrodynamical evolution Hard scattering (PDF and Jets) correctly described First test with LHC data Good in average Inconsistency pt/multiplicity : more checks needed No dramatic change for air shower development Next step : Selection of hard processes Both at the same time : underlaying events

slide-17
SLIDE 17
  • T. Pierog, KIT - 17/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

Air Shower Development

Muons affected by baryon production

slide-18
SLIDE 18
  • T. Pierog, KIT - 18/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

<pt> vs multiplicity : EPOS 1.61 (2007)

Since 2007 collective effects in EPOS for any system :

Minimum energy density needed to start formation of “core clusters” Microcanonical decay with additional flow Flow parametrized from SPS HI, RHIC HI and Tevatron ap-p ap-p 1.8 TeV (fit) p-p 14 TeV (prediction)

“HI at LHC : Last Call for Predictions” Armesto et al.

More development on collective effects in pp from other groups :

D'Enterria et al. (arXiv:0910.3029), Solana et al. (arXiv:0911.4400), Chaudhuri (arXiv:0912.2578), ...

  • K. Werner

Phys.Rev.Lett.98:152301,2007.

slide-19
SLIDE 19
  • T. Pierog, KIT - 19/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

Hydro in pp : Initial Conditions

Initial conditions from multiple interactions :

Energy density comparable to AuAu@RHIC Size comparable to size of fluctuations in AuAu@RHIC

We propose (and we do) for pp :

Hydrodynamical expansion + statistical decay based on EPOS flux tube initial conditions (event-by-event)

slide-20
SLIDE 20
  • T. Pierog, KIT - 20/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

Initial Conditions ap-p@Tevatron

slide-21
SLIDE 21
  • T. Pierog, KIT - 21/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

First Real Hydro in ap-p@1.8 TeV : Tau

Apply same parameters as for AuAu@RHIC

(except flux tube radius = free parameter) τ=0.6 τ=1.0 τ=1.4 τ=2.5 τ=2.1 τ=1.7 2 25 9 0.6 1.2 3 60

  • 2

2

slide-22
SLIDE 22
  • T. Pierog, KIT - 22/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

Initial Conditions AuAu@RHIC

slide-23
SLIDE 23
  • T. Pierog, KIT - 23/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

EoS

slide-24
SLIDE 24
  • T. Pierog, KIT - 24/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

AuAu : Kaon

slide-25
SLIDE 25
  • T. Pierog, KIT - 25/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

AuAu : Lambda

slide-26
SLIDE 26
  • T. Pierog, KIT - 26/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

AuAu : Di-hadron correlation

slide-27
SLIDE 27
  • T. Pierog, KIT - 27/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

p-p : Other Possible Observable

slide-28
SLIDE 28
  • T. Pierog, KIT - 28/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

Pt distribution CDF ap-p@1.8 TeV with Hydro

slide-29
SLIDE 29
  • T. Pierog, KIT - 29/16

XVIth ISVHECRI – June 2010

The EPOS model New developments Preliminary results

Pt distribution CDF ap-p@1.8 TeV without Hydro