The Compressed Baryonic Matter Experiment at FAIR

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

2. Landscape of Discovery in Super-Dense Matter Physics energy ALICE@LHC ALICE upgrade STAR@RHIC terra incognita Shine@SPS RHIC BES MPD@NICA CBM@SIS300 Shine BES CBM@SIS100 luminosity 51. International Winter Meeting on Nuclear Physics, Bormio

3. Current and Future Experiments on SuperdenseNuclear Matter 51. International Winter Meeting on Nuclear Physics, Bormio

4. Coveringthe High Baryon DensityRegime BES@RHIC NA61@SPS CBM@FAIR MPD@NICA Maximal net-baryon density (fromhadron gas model): Ebeam ≈ 30A GeV (√sNN ≈ 8 GeV) 51. International Winter Meeting on Nuclear Physics, Bormio

5. Experiments on Superdense Nuclear Matter rare probes 51. International Winter Meeting on Nuclear Physics, Bormio

6. 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 51. International Winter Meeting on Nuclear Physics, Bormio

7. Structureof Neutron Stars M. Orsaria, H. Rodrigues, F. Weber, G.A. Contrera Phys. Rev. D 87, 023001 (2013) • recent observationof a Neutron Star • nostableagainstgravitationalcollapswith soft EOS (e.g. quark matter EOS) • stable Neutron Star with quark-hadron mixed phase incl. hyperons • important: knowledgehyperon-hyperon interaction 51. International Winter Meeting on Nuclear Physics, Bormio

8. Densities in Neutron Stars and in Nuclear Collisions W. Cassing, E.L. Bratkovskaya, Phys. Rep. 308, 65 (1999) Experimental Prerequisites: highestbaryondensitiesreached in AA collisionaround() probesof high densityphase (are traditional flowmeasurementssuffient?) 51. International Winter Meeting on Nuclear Physics, Bormio

9. Exploring the EOS at 3ρ0 < ρ < 7ρ0 with (Sub)-Threshold Production of Multi-Strange Hyperons yield/week • Direct production: • Production via multiple collisions*): • sub-threshold production cross section of , probes dense, baryonic matter…. • AGS physics revisited with new probes • measure excitation functions for multi-strange hyperons in light and heavy collision system AGS SPS *) P. Chung et al, E895 Coll. PLR 91.202301(2003) G. Agakishiev et al, Hades Coll, PRL 103, 132301 (2009) SIS100 51. International Winter Meeting on Nuclear Physics, Bormio

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

11. Double-strange hypernuclei ObservedΛΛhypernuclei: 1963: ΛΛ10Be (Danysz et al.) 1966: ΛΛ6He (Prowse et al.) 1991: ΛΛ10Be orΛΛ10Be (KEK-E176) 2001: ΛΛ4H (BNL-E906) 2001: ΛΛ6He (KEK-E373) 2001: ΛΛ10Be (KEK-E373)

12. Search for Double Hypernuclei conventional production mechanism*): A. Andronic, P. Braun-Munzinger, J. Stachel, H. Stöcker , PL B697 (2011) 204 + heavy collisions: production via coalescence of with light fragments 40 AGeV: 50 /central Au+Au collision 10 AGeV: 15 /central Au+Au collision yield: /central collision coalecense probability has maximum at 120/week 3.6/week 51. International Winter Meeting on Nuclear Physics, Bormio *) Takahashi et al, PRL 87 (2001)

13. Being prepared for exotica: Experimental Reconstruction of a Multistrange Di-Baryon p p- L2 p (X0L)b L1 p- Signal: strange dibaryon (0)b   (cτ=3cm) M= 10-6, BR = 5% Background: Au+Au @ 25 AGeV 32  per central event 11  reconstructable I. Vassiliev, Univ. Frankfurt 51. International Winter Meeting on Nuclear Physics, Bormio

14. CBM @ FAIR EM Calorimeter bulk observables hyperons, charm • 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 Ring Imaging CherencovHodoscope Muon Detection System Silicon Tracking System PS Calorimeter di-electrons charmonium Micro Vertex Detector Transition Radiation Detectors Resistive Plate Chambers (TOF) Hades CBM Start Version CBM Full Version 51. International Winter Meeting on Nuclear Physics, Bormio

15. CBM Cave Undergound Status: Layout defined, drawingsapproved, furthermodificationsrequire "changerequest" 51. International Winter Meeting on Nuclear Physics, Bormio

16. Rare Probes, High Rates • Requirement for a high rate expiment: • fast and rate-capabledetectors • fast read-out electronics • radiation-harddetectorsandelectronics • high-throughputdataacquisitionandefficient online dataselection newterritoryfrom a detector,electronics, trigger/computingpointofview! 51. International Winter Meeting on Nuclear Physics, Bormio

17. Detector systems • Main trackingdevice: STS • low-masssiliconstripdetectors in magneticdiplolefield • trackingefficiency > 90 % • momentumresolution ≈ 1% • Micro-vertex detectorfor open charm: MVD • low-masssiliconpixeldetectorclosetothetarget • high precision (resolution ≈ 3 μm) • Electronidentication: RICH and TRD • RICH with C02radiator, twofocal planes andMAPMT photodetection • severallayersofthin TRDs with MWPC readout • Hadronidentification: TOF • RPC wall at 10 m flightdistance, resolution <≈ 80 ps • Muonidentification: activeabsorbersystem • severalabsorber / GEM detectorlayers • ECAL forphotonandelectronidentification • lead/scinitillatorsandwich • Event characterisation: PSD • compensatedforwardcalorimeter lowmass, radiationhard! newtechnology: high rate & resolution MAPS ! newtechnology: fastTRD! newtechnology: high rate & resolution RPC ! newtechnology: GEM instrumentedabsorber! 51. International Winter Meeting on Nuclear Physics, Bormio

18. CBM Start-Version: Micro-Vertex Detector The keyto open charmis a high-precision, ultralow-massvertexdetector • MAPS: integratedelectronics, verylow material budget, veryprecise(3 μm) • Not intrisically fast andradiationhard, but tremendeousprogress: 40 μs r/o frame, standsupto 1013neq/cm2 • nowalmost „stateoftheart“ (STAR, ALICE, NA61 upgrades) MIMOSA 26 station design prototype 51. International Winter Meeting on Nuclear Physics, Bormio

19. CBM Start-Version: Silicon Tracking System 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 ~1m 51. International Winter Meeting on Nuclear Physics, Bormio

20. The Big Challenge: Data Reduction Online Data Processing CBM FEE 1 GB/s 1 TB/s freesteamingdataflow Mass Storage • No a-priori association of signals to physical events! • „Event building“ becomes non-trivial at high rates • Need extremely fast reconstructionalgorithms! At 10 MHz, online datareductionby ≈ 1000 ismandatory Trigger signaturesarecomplex (open charm) andrequirepartial eventreconstruction 51. International Winter Meeting on Nuclear Physics, Bormio

21. CBM Time Line CBM cave ready: May 1, 2017 SIS100 ready: Oct. 13, 2017 51. International Winter Meeting on Nuclear Physics, Bormio

22. CBM Collaboration (55 Labs, 400 People) 51. International Winter Meeting on Nuclear Physics, Bormio