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The ASYEOS Experiment at GSI

Presentation by Simon GannonUniversity of LiverpoolSupervisors: M. Chartier

R. Lemmon

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Background and Motivation• Objective: to investigate the

density dependence of the symmetry energy

• Symmetry Energy for asymmetric nuclear matter poorly constrained at high densities

• Important for understanding physics in neutron stars and supernovae

Figure adapted from presentation by B.Tsang

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The ASYEOS Experiment• How do you study high density

nuclear matter in the laboratory– Heavy Ion Collisions at

intermediate energies used to produce a high density region

• Investigated the systems – 197Au-197Au, 96Ru-96Ru and 96Zr-96Zr @ 400AMeV

• Elliptic flow of protons and neutrons will be measured

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Proton and Neutron Flow• Neutron/proton elliptic

flow ratio is predicted to be sensitive to the the symmetry energy

0 0.5 1

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Setup of the ASYEOS Experiment

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LANDSketch of Detector anda single paddle unit

LAND Timing Electronics use a timing system which has a 40MHz clock cycle

Figures taken from: The LAND Collaboration, Nuclear Instruments and Methods in Physics Research A314 (1992) 136-154

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Status of Analysis• Reaction plane has been

determined using CHIMERA and Microball

• A fault in some new electronics on LAND has delayed the analysis

• Preliminary values of v2 have been determined for protons

• Neutron v2’s will follow after LAND data has been corrected

Figure from P.Russotto Phys.Lett.B 697: 471-476, 2011

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Summary

• Preliminary determination of reaction plane and v2 have been completed

• The problem with the LAND timing electronics has delayed the analysis

• Corrections to the LAND data are well underway and should allow recovery of vast majority of the corrupted data

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ASYEOS CollaborationS. Gannon2, M. Chartier2, E. De Filippo1, A. Le Fevre3, I. Gasparic4,5,M. Kis3,4,

S. Kupny6, Y. Leifels3, R.C. Lemmon7, J. Łukasik8, P. Marini9,10, A. Pagano1,P. Pawłowski8, P. Russotto1, S. Santoro11,12, W. Trautmann3, M. Veselsky13, L.Acosta14, M. Adamczyk6, A. Al-Ajlan15, M. Al-Garawi16, S. Al-Homaidhi15,

F.Amorini14, L. Auditore11,12, T. Aumann5,Y. Ayyad17, V. Baran14,18, Z. Basrak4, J. Benlliure17, C. Boiano19, M. Boisjoli10, K.Boretzky3,J. Brzychczyk6, A.Budzanowski8,

G. Cardella1, P. Cammarata9, Z. Chajecki20, A. Chbihi10,M. Colonna14, D. Cozma21, B. Czech8, M. Di Toro14,22, M. Famiano23, E. Geraci1,22, V.

Greco14,22,L. Grassi4,C. Guazzoni19,24, P. Guazzoni19,25, M. Heil3, L. Heilborn9, R.Introzzi26, T. Isobe27,K. Kezzar16, A. Krasznahorkay28, N. Kurz3, E. La Guidara1,

G.Lanzalone14,29, P. Lasko6, Q. Li30,I. Lombardo31,32, W. G. Lynch20, Z. Matthews2, L. May9,T. Minniti11,12, M. Mostazo17, M. Papa1,S. Pirrone1, G. Politi1,22, F.Porto14,22, R. Reifarth3, W. Reisdorf3, F. Riccio19,25, F. Rizzo14,22,E. Rosato31,32, D.Rossi3, H. Simon3, I. Skwirczynska8, Z. Sosin6, L.Stuhl28,A.Trifir`o11,12,M.Trimarchi11,12,M. B. Tsang20, G. Verde1, M. Vigilante31,32, A. Wieloch6, P. Wigg2,H. H. Wolter33, P. Wu2, S. Yennello9,

P. Zambon19,24, L.Zetta19,25, M. Zoric4

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