PentaQuark analysis History

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PentaQuark analysis History

• Analysis channels for G10
• Analysis channels for G11
• X5 States and Decays

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1. Analysis channels for G10
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2. Analysis channels for G11
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X5 States and Decays
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Production Diagram
X5- -
X5- - is composed of (ssddu) quarks
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Schematic of the Reaction
X - - ? p - X-
X - ? p - L
L ? p - p
Photon beam
gn?KKX5--

• X- ct 4.9 cm
• ct 7.9 cm

Detached Vertices can be helpful
Two decay vertices, Negatives bend outwards
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EG3 Conditions

• Use CEBAF 5.7 GeV initial electron beam.
• Secondary tagged photon beam within a tagging
  range from 4.5-5.5 GeV at 2x107sec-1 tagged
  g-rate.
• 40-cm long deuterium target 50 cm to achieve
  integrated luminosity of 100 pb-1 for active
  tagging range.
• Reversed magnetic field polarity to improve the
  acceptance for the negative tracks .
• Use 3-tracks trigger as the main trigger.
  Prescaled 2-track trigger.
• Collected total of 4 billion triggers (2 track
  3 track) in 40 calendar days.

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Status of F(1860) Search
Ageev et al, Eur. Phys. J C41 (2005)
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Kinematical Coverage

• The coverage for K- is better than for K .
• Cannot afford to tag strangeness with two Ks.
• Still, can require one K detection to clean up
  the data sample by losing 70 in statistics.

Hovanes' plots
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