strange baryon resonances
DESCRIPTION
Strange Baryon Resonances. Christina Markert, Yale University. Motivation Results (1520) ,(1385) and (1530) from p+p, Au+Au and first d+Au Data Summary and Future Plans. Christina Markert, Sevil Salur, Richard Witt (Yale/Bern), Ludovic Gaudichet (Subatech/Nantes). - PowerPoint PPT PresentationTRANSCRIPT
Strange Baryon Resonances
Christina Markert, Yale University
DOE Meeting at Yale, September 2003
• Motivation • Results (1520) ,(1385) and (1530)
from p+p, Au+Au and first d+Au Data• Summary and Future Plans
Christina Markert, Sevil Salur,
Richard Witt (Yale/Bern),
Ludovic Gaudichet (Subatech/Nantes)
Resonances in Medium
Short life time [fm/c] < < K* < * < * < * < 1.3<1.7< 4 < 6 < 13 < 20 < 40
• Strangeness enhancement ? • Temperature at chemical freeze-out ? Yield (Thermal models)• Time between chemical and kinetic freeze-out ? Rescattering and regeneration of resonance decay particles Yield and pt spectra (Microscopic models UrQMD)
Resonance reconstruction in STAR TPC
(1520)
K-
p
(1520)
(1385), (1530)
*-+- -+-
*+++
*-+-
*+++ +++
* +
__ __
______ __ (1520) p +K- , p +K+
_
End view
Front view
Strange Resonances Signals in p+p at 200 GeV
*
(1385)
preliminary
mass 1.516 0.001 GeVwidth 18 MeV fixed
(1520)
Mixed technique
V0 technique
(1530)
Mixed technique
V0 technique
Resonance pt Spectra in p+p at 200 GeV
<pT> 0.92 0.03 GeV
(1520)
preliminary
(1385) and (1530) enough statistics corrections still underway
Mean pt in p+p at 200 GeV
<pt> for high mass resonances in p+p higher than particles with same mass ?
Helen SQM2003
(1520)
(1385)? (1530) ?
Strange Resonance Production in Au+Au Collisions
(1520)
No mass shift or width broadening visible
(1385)
Thermal description: Chemical freeze-out temperature Tch = 120 MeV
Microscopic model : Time span between chemical and kinetical freeze-out = 5-10 fm/c. (1385) ? analysis on the way
Tch = 175 MeV
Resonance Production in p+p and Au+Au
preliminary
Tch = 120 MeV
Decrease from p+p to A+A at 200GeV : 70% ± 45%
UrQMD Microscopic model
Summary + Future Plans
• Measure (1520) ,(1385) ((1530)) in p+p, d+Au and Au+Au collisions.• High mean pt in p+p for (1520) and (1385) . • Strange resonance/non resonance ratio shows decrease in Au+Au collisions compared to p+p collisions. Tchem =120 MeV (thermal model) .Or Time between chem. and kin. freeze-out = 5-10 fm/c (microscopic model).
Future Plans:• Complete d+Au and Au+Au analysis • write resonance paper (d+Au, p+p and Au+Au)
• Put together results from (*,*,*) with , , K* and , compare it with theoretical predictions.• Resonance meeting at Yale in Dec2002, plan to have another resonance meeting later this year.
• Full pt spectra for (1520) and (1530) with higher statistics from upcoming Au+Au run.