The Compressed Baryonic Matter Experiment at FAIR Physics Program, Challenges and Status

Landscape of Discovery in Super-Dense Matter Physics 2 energy luminosity ALICE upgrade SPS RHIC BES 51. International Winter Meeting on Nuclear Physics, Bormio Shine BES

ExperimentEnergy range (Au/Pb beams) Reaction rates Hz BNL  s NN = 7 – 200 GeV 10 – 800 (limitation by luminosity at low beam energies) CERN E kin = 20 – 160 A GeV  s NN = 6.4 – 17.4 GeV 80 (limitation by detector/TPC) Dubna  s NN = 2.0 – 11.0 GeV ~1000 (collider: design luminosity of cm -2 s -1 for heavy ions) Darmstadt E kin = 2.0 – 11(35) A GeV  s NN = 2.5 – 4.8(8.2) GeV 10 5 – 10 7 (limitation by present detector technology) Current and Future Experiments on Superdense Nuclear Matter International Winter Meeting on Nuclear Physics, Bormio

Covering the High Baryon Density Regime 4 Maximal net-baryon density (from hadron gas model): E beam ≈ 30A GeV (√s NN ≈ 8 GeV) 51. International Winter Meeting on Nuclear Physics, Bormio

ExperimentObservables for beam energies below  s NN = 12 GeV (high baryon density region) hadronscorrelations, fluctuations dileptonsmulti- strange, charm BNL yes no CERN yes no Dubna yes no Darmstadt yes Experiments on Superdense Nuclear Matter 5 rare probes 51. International Winter Meeting on Nuclear Physics, Bormio

Outline Focus of this talk – Exploration of Dense Matter with new, rare probes (sub)threshold production of multi-strange hyperons hyper-nuclei – Experimental Challenges & Status of CBM No covered (because of time constraints) – bulk observables flow, fluctuations, correlations, …. – Hadrons in Dense Matter low mass vector mesons charm & open charm International Winter Meeting on Nuclear Physics, Bormio

Structure of Neutron Stars International Winter Meeting on Nuclear Physics, Bormio M. Orsaria, H. Rodrigues, F. Weber, G.A. Contrera Phys. Rev. D 87, (2013)

Densities in Neutron Stars and in Nuclear Collisions W. Cassing, E.L. Bratkovskaya, Phys. Rep. 308, 65 (1999) International Winter Meeting on Nuclear Physics, Bormio

Exploring the EOS at 3ρ 0 < ρ < 7ρ 0 with (Sub)- Threshold Production of Multi-Strange Hyperons 9 *)P. Chung et al, E895 Coll. PLR (2003) G. Agakishiev et al, Hades Coll, PRL 103, (2009) AGS SPS SIS100 yield/week 51. International Winter Meeting on Nuclear Physics, Bormio

Multi-Strangeness 10 H. Stöcker et al., Nucl. Phys. A 827 (2009) 624c *) Metastable Exotic Multihypernuclear Objects 51. International Winter Meeting on Nuclear Physics, Bormio

Observed ΛΛ hypernuclei: 1963: ΛΛ 10 Be (Danysz et al.) 1966: ΛΛ 6 He (Prowse et al.) 1991: ΛΛ 10 Be or ΛΛ 10 Be (KEK-E176) 2001: ΛΛ 4 H (BNL-E906) 2001: ΛΛ 6 He (KEK-E373) 2001: ΛΛ 10 Be (KEK-E373) Double-strange hypernuclei 11

Search for Double Hypernuclei 12 conventional production mechanism *) : *) Takahashi et al, PRL 87 (2001) 3.6/week120/week + A. Andronic, P. Braun-Munzinger, J. Stachel, H. Stöcker, PL B697 (2011) International Winter Meeting on Nuclear Physics, Bormio

   b   p p   Signal: strange dibaryon (  0  ) b   (cτ=3cm) M= 10 -6, BR = 5% Background: 25 AGeV 32  per central event 11  reconstructable Being prepared for exotica: Experimental Reconstruction of a Multistrange Di-Baryon 13 I. Vassiliev, Univ. Frankfurt 51. International Winter Meeting on Nuclear Physics, Bormio

FAIR 14 FAIR Modules 0-3 (SIS100): protons up to 29 GeV Au+Au 11 AGeV, Ca+Ca 14 AGeV  HADES + CBM Start Version FAIR Module 6 (SIS300): protons up to 89 GeV Au+Au 35 AGeV, Ca+Ca 44 AGeV  CBM HadesCBM Start Version bulk observables hyperons, charm di-electrons charmonium Micro Vertex Detector Ring Imaging Cherencov Hodoscope Silicon Tracking System Transition Radiation Detectors Resistive Plate Chambers (TOF) EM Calorimeter PS Calorimeter Muon Detection System CBM Full Version 51. International Winter Meeting on Nuclear Physics, Bormio

Status: Layout defined, drawings approved, further modifications require "change request" CBM Cave Undergound International Winter Meeting on Nuclear Physics, Bormio

Rare Probes, High Rates International Winter Meeting on Nuclear Physics, Bormio

Detector systems Main tracking device: STS – low-mass silicon strip detectors in magnetic diplole field – tracking efficiency > 90 % – momentum resolution ≈ 1% Micro-vertex detector for open charm: MVD – low-mass silicon pixel detector close to the target – high precision (resolution ≈ 3 μm) Electron identication: RICH and TRD – RICH with C0 2 radiator, two focal planes and MAPMT photo detection – several layers of thin TRDs with MWPC readout Hadron identification: TOF – RPC wall at 10 m flight distance, resolution <≈ 80 ps Muon identification: active absorber system – several absorber / GEM detector layers ECAL for photon and electron identification – lead/scinitillator sandwich Event characterisation: PSD – compensated forward calorimeter International Winter Meeting on Nuclear Physics, Bormio low mass, radiation hard! new technology: high rate & resolution RPC ! new technology: GEM instrumented absorber! new technology: high rate & resolution MAPS ! new technology: fast TRD!

CBM Start-Version: Micro-Vertex Detector 18 MIMOSA 26station designprototype The key to open charm is a high-precision, ultra low-mass vertex detector – MAPS: integrated electronics, very low material budget, very precise (3 μm) – Not intrisically fast and radiation hard, but tremendeous progress: 40 μs r/o frame, stands up to n eq /cm 2 – now almost „state of the art“ (STAR, ALICE, NA61 upgrades) 51. International Winter Meeting on Nuclear Physics, Bormio

19 CBM Start-Version: Silicon Tracking System ~1m double sided silicon microstrip detector 15° stereo angle, 60 µm pitch, 300 μm thick, bonded to ultra-thin micro-cables, radiation hardness 2.5 mm 51. International Winter Meeting on Nuclear Physics, Bormio

The Big Challenge: Data Reduction 20 At 10 MHz, online data reduction by ≈ 1000 is mandatory Trigger signatures are complex (open charm) and require partial event reconstruction Online Data Processing 1 TB/s CBM FEE 1 GB/s Mass Storage No a-priori association of signals to physical events! „Event building“ becomes non-trivial at high rates Need extremely fast reconstruction algorithms! free steaming data flow 51. International Winter Meeting on Nuclear Physics, Bormio

CBM Time Line R&D detectors & read-out systems construction detectors & read-out systems installation, commissioning first data taking CBM cave ready: May 1, 2017 SIS100 ready: Oct. 13, International Winter Meeting on Nuclear Physics, Bormio

CBM Collaboration (55 Labs, 400 People ) International Winter Meeting on Nuclear Physics, Bormio