The National Superconducting Cyclotron Laboratory @Michigan State - PowerPoint PPT Presentation

The National Superconducting Cyclotron Laboratory @Michigan State University U.S. flagship user facility for rare isotope research and education in nuclear science, astro-nuclear physics, accelerator physics, and societal applications Betty Tsang for the Collaboration JCNP2015, Osaka, November 8, 2015 Nuclear Symmetry Energy: From Nucleus to Neutron Stars

Michigan State University

From NSCL to Facility for Rare Isotope Beams (FRIB)

FRIB Construction Progress March 17, 2014 above ground! April 1, 2015 $730 M project: 2009 – 2020 (early completion) November 4, 2015

Symmetry Energy Project LAMPS FRIB GSI NSCL RAON GANIL IMP TAMU Catania RIBF Yennello Natowitz Indra RB3, Hades ASY-EOS CEE HiRA International Collaboration is the key 3

JUSTIPEN provide funds for US scientists to travel to RIBF… to collaborate with Japanese scientists 2011-FUSTIPEN 2006-2014

Time to change “Theory” to “Experiment)” (2009) E JUSEIPEN provide JUSTIPEN provide funds funds for US scientists for US scientists to travel to travel to RIBF… to RIBF… to collaborate with Japanese scientists

10 workshops and counting

Nuclear Symmetry Energy: From Nucleus to Neutron Stars 曾敏兒 -- Betty Tsang Outline 1. Introduction : Different forms of EoS 2. How did we get here? Current constraints on density dependence of symmetry energy. 3. Where are we going? Future challenges and opportunities. 4. Research funded by DOE, NEXT and JUSEIPEN. 5. Summary

Nuclear Symmetry Energy: From Nucleus to Neutron Stars Equation of State of nuclear matter E/A ( ρ , δ ) = E/A ( ρ ,0) + δ 2 ⋅ S( ρ ) δ = ( ρ n - ρ p )/ ( ρ n + ρ p ) = (N-Z)/A Symmetry Energy of asymmetric matter 208 Pb  To probe fundamental questions on the nature of nuclear matter especially the isospin asymmetric matter.  To recreate and study astrophysical environments

Symmetry Energy − Z ( Z 1 ) Image by Andy Sproles, ORNL = − 2/3 − B a A a A a C V S 1 / 3 A − 2 ( 2 ) A Z − a sym A − 2 ( A 2 Z ) − Proton V S 2 / 3 ( a A a A ) 2 sym sym A Inclusion of surface terms in symmetry Hubble ST Neutron

From Masses Recommendation to Skyrme interactions US Long Range Plan from EOS working group SE>0  At ρ<<ρ 0 : Establish observables to study cluster effect and link to neutrinosphere physics.  At ρ≤ρ 0 : Improve constraints from both structure and reaction experiments:  At ρ ≈ 1.5 - 2 ρ 0 : Determine symmetry energy and the momentum dependence of the isovector potential.

Isospin Diffusion observable to study E sym with Heavy Ion Collisions γ i S ( ρ )=12.5( ρ / ρ o ) 2/3 + C ( ρ / ρ o ) δ =(N-Z)/A Tsang, Shi et al., PRL92, 062701(2004) Tsang et al., PRL 92 (2004) 062701 Small Esym Projectile 124 Sn Large Esym Target 112 Sn Isospin Diffusion; low ρ , E beam δ − δ + δ ( ) / 2 = AB AA BB R 2 δ − δ i AA BB Bao-An Li et al., Phys. Rep. 464, 113 (2008) Tsang, Zhang et al., PRL122, 122701(2009)

Status of Constraints from nuclear structure and reactions   ρ − ρ L ( ) S ( ρ )=12.5( ρ / ρ o ) 2/3 + C ( ρ / ρ o ) ρ = + + B 0 S S ...   ρ o   3 0 Tsang et al, 86, 015803 (2012) neutrinosphere

Consistent Constraints from nuclear structure and reactions with credible uncertainties NuSYM13 & ICNT2013   ρ − ρ L ( ) ρ = + + B 0 S S ...   ρ o   3 Tsang et al, 86, 015803 (2012) 0 ρ mass <0.45 ρ 0 ρ mass ≈ 0.6- 0.7 ρ 0 ( ) S ( ρ )=12.5( ρ / ρ o ) 2/3 + C ( ρ / ρ o ) ρ = ρ − 0 1 3 M ; M is slope sens.

Equation of State of Neutron Matter Hubble ST Neutron Star: balance of Gravity (pulls in) and Symmetry energy pressure (pushes out): Masses vs. Radii EoS of pure neutron matter: Symmetry Energy as function of pressure (density)

Lattimar & Prakash

Recent observations of Neutron Stars (radius/Radii) Lattimar & Prakash S. Guillot, et al Astrophys. J. 772, 7 (2013), 1302.0023 too soft Steiner Suleimanov Very small Neutron Star radius rules out nearly all EOS

Density dependence of symmetry energy at supra-saturation density Wiringa, Fiks, & Fabrocini 1988 Skyrme interactions Neutron Star obs. HIC Above saturation density, the symmetry energy density dependence may have a different energy dependence than Skyrme interactions.

Pion Observable Pros: • Produced in direct n p • Pion ratios are most sensitive collisions – sensitive to compared to n/p or t/3He rtaios symmetry energy • Differences of pion spectra are • exit in early time more sensitive than ratios of Cons: integrated yields. • Cross-section is low and • A new detector is needed to • Easily reabsorbed in collision probe these observables medium

New Detector Radioactive Beam: • low luminosity  large coverage High Resolution: • resolve many different species of produced particles • distinguish particles by mass and charge ( π + , π - ) • track particles in an applied magnetic field Versatile for a wide range of experimental programs

Time-Projection Chamber 2D path in horizontal plane from pad positions • Products from reaction B field ionize detector gas inside a field cage • Electron signal is E field amplified by a wire plane x • The time at which the electrons hit the pads y provides the third dimension Position in vertical direction from drift time

2006 March RIKEN workshop, by Bill Lynch Possible RIKEN (EOS) program July 23, 2014 collaboration

Joint US-Japan project US Collaboration: Japanese collaboration: NEXT December/2008: submit DOE FOA Part of “Material Science of Quarks” proposal for $1.2 M ~100 M yen for TPC electronics, November/2009: Proposal approved Ancillary trigger scintillation array, (CAGRA, SAMURAI-Si, Targets, TPC gas handling system ,TPC JUSEIPEN) laser calibration system, Data October/2010: Project start date; acquisition Construction & Shipment of TPC, and travel (help from JUSEIPEN) Approved experiments at RIKEN δ CN Primary Secondary Target 132 Sn 124 Sn 0.22 238 U 124 Sn 112 Sn 0.15 108 Sn 112 Sn 0.09 124 Xe 112 Sn 124 Sn 0.15

Day 1 experiment: Triggered by multiplicity and beam veto :Trigger scintillators use MPPC (multi-pixel Photon Counter) readout MPPC ranges from 1x1 to 3x3 mm 2 Yan Zhang, THU

Anatomy of Rigid Top Plate Primary structural member, Front End Electronics reinforced with ribs. 2011-2013 STAR FEE for testing, Holds pad plane and wire ultimately use GET planes. Pad Plane ( 12096 pads) Field Cage Mounted to bottom of Defines uniform electric field. top plate. Used to measure Contains detector gas. particle ionization tracks Wire Planes (e- mult) Mounted below pad plane. 0.5m Provide signal multiplication Beam and gate for unwanted events Calibration Laser Optics Voltage Step-Down Target Mechanism Prevent sparking from cathode (20kV) to ground Thin-Walled Enclosure Protects internal components, seals insulation gas volume, and supports pad plane while Rails allowing particles to continue For inserting TPC into on to ancillary detectors. SAMURAI vacuum chamber

May, 2013 Feb, 2014 Feb, 2014 July, 2014 August, 2015

On Site Experimenters Commissioning of outside SAMURAI (10/23 & 29) J. Barney (MSU) G. Cerizza (MSU) J. Estee (MSU) T. Isobe (RIKEN)* G. Jhang (Korea U) M. Kaneko (Kyoto U) Y. Kim (RISP) M. Kurata-Nishimura (RIKEN) P. Lasko (IFN, Krakow) H. Lee (RISP) J. Lee (Korea U) J. Lukasik (IFN, Krakow) W. Lynch (MSU)* T. Murakami (Kyoto U)* P. Pawlowski (IFN, Krakow) K. Pelczar (IFN, Krakow) C. Santamaria (MSU) D. Suzuki (RIKEN) B. Tsang (MSU)* Y. Zhang (Tsinghua U) *spokesperson

Commissioning of Cosmic Events October, 2015

79Se+Sn 200 MeV/u Event from Kyoto multiplicity>0 multiplicity>1 trigger + beam veto multiplicity>2 Event from Katana central trigger + beam veto October 29, 2015

Commissioning of outside SAMURAI October 29, 2015

Wire planes • Anode and ground plane creates avalanche region for electrons • Anode plane induces image charge on the pad plane • Gating grid closes off amplification region when not triggered Plane height pitch diameter( µ m) (mm) (mm) Anode 4.05 4 20 Ground 8.1 1 75 Gating 14 1 75 grid Bottom view of lid

Gating grid (Suwat Tangwancharoen) mm -115 V GG open cm 0 0.5 1.0 mm -150 -80 -150 V Transmission Justin Estee Hyo Sang Lee GG closed cm Data vs. Garfield simulation Yao-Feng Zhang, BNU S. Tangwanchoren -200 -100 0 J. Justin Vgg (Volt)

Challenge I: Analysis of Event from Kyoto multiplicity>0 multiplicity>1 trigger + beam veto Commissioning Data (4 TB) multiplicity>2 Event from Katana central trigger + beam veto October 29, 2015

δ Primary Secondary Target 132 Sn 124 Sn 0.22 Scintillator 238 U Trigger 124 Sn 112 Sn 0.15 Array 108 Sn 112 Sn 0.09 124 Xe 112 Sn 124 Sn 0.20 SAMURAI Spectrometer Challenge II: Completion of proposed experiments