Asymmetry Measurement of the Polarized Σp Elastic
Scattering and the Hyperon-Nucleon Spin-Orbit Interaction(KEK-PS E452)
T. Kadowaki, J. Asai, W.Imoto, S. Iwata, M. Kurosawa, K. Nakai
A. Sato, K. Imai, H. Takahashi, C.J. Yoon, T. Maruta, M. Ieiri
T. Nagae, H. Noumi, T. Fukuda, P.K. Saha, B. Bassalleck
Department of Physics, Tokyo University of Science
Department of Physics, Osaka University
Department of Physics, Kyoto University
Department of Physics, University of Tokyo
High Energy Accelerator Research Organization (KEK)
Laboratory of Physics, Osaka Electro-Communication UniversityDepartment of Physics, University of New Mexico

E452 Publications
Physics papers published in refereed journals
Hyperon Scattering Experiments with a new Tracking Detector 'SCITIC'.
J. Asai, T. Fukuda, M. Ieiri, K. Imai, W. Imoto, S. Iwata, T. Kadowaki, M. Kurosawa, T. Maruta,
C.J. Yoon, K. Nakai : Jpn. J. Appl. Phys. vol.43, pp.1586-1592 (2004)

T. Nagae, H. Noumi, P.K. Saha, A. Sato, H. Takahashi,

Spin –Dependent Interactions in Hyperon Nucleon Scattering
K. Nakai : Nucl.. Phys. vol.A721, pp.673-678 (2003)

Asymmetry Measurement of the Polarized Σ+ P Elastic Scattering and the Hyperon Nucleon Spin-Orbit Interaction.
T. Kadowaki, J. Asai, W. Imoto, S. Iwata, M. Kurosawa, K. Nakai, A. Sato, K. Imai, H. Takahashi, C.J. Yoon, T. Maruta, M.Ieiri, T. Nagae, H. Noumi,
T. Fukuda, P.K. Saha, B. Bassalleck, : Eur. Phys. J. vol.A15, pp.295-298 (2002)

Scintillating Track Image - SCITIC.
By A. Sato, J. Asai, M. Ieiri, S. Iwata, T. Kadowaki, M. Kurosawa, T. Nagae, K. Nakai. : Jpn. J. Appl. Phys. vol.43, pp.1593-1601 (2004)

Doctor theses
Akira Sato (2001) : Development of a New Tracking Detector for Hyperon-Nucleon Scattering Experiments (in Japanese)
Tetsuto Kadowaki (2002) : Asymmetry Measurement of the Polarized Hyperon-Nucleon Elastic Scattering
Jyunkichi Asai (2004) : Measurements of asymmetry and depolarization parameters in the polarizedΣ +p elastic scatteringMotivationPovh & Pirner
VcΛN ＝ (2/3)VcNN
VLS

ΛN~0Λhyperons I=1/2ud I= 0]

xNucleiududYazakiΛNVSLSΛN ~ーVALSーsud

ΣhyperonVLS

ΣNLarge ??
NucleiX Σhypernuclear experiments⇨ Scattering exp. of polarized hyperonsudud

I=1/2] I= 1

Active Target Tracking Detectors
1950‘s M. Perl : Luminescent Chamber
1970‘s Bubble chambers for hyperon experiments
1990‘s SCIFI detectors by the Kyoto/Nagoya group
1992

Hazumi & Yamada at INS : use of a bulk scintillator

1995

D.Measday at KAON workshop : why not bulk scintillator ?

1995 Knoll exercise in his textbook: can you see a track of β-ray with your eye?
1990 SCITIC (Scintillating track image camera)
1999 Proposal of E452 with SCIFI and SCITIC : cosmic muons, beams (T457, T467)
2000 E452A with SCITIC : the first use of SITIC for a physics experiment.
2001 E452B&C with new SCITIC : analysis of SCITIC data

Production of Polarized Σ+p(π +,K +)Σ+, at Eπ=1.67 GeVSpectrometer

SCITIC

K++πΣ+pΣ
Active target(Liquid Scintillator)+’

left/right asymmetry

NL-NR
A= N +NLR

Spectrometer acceptance

E289

E452

E452AEvent-selection statistics
Triggered events

600,000invariant -mass cut, vertex cut(π,K) events

60,000Eye scanningΣ p candidates+

500

Pointing, 3D-reconstruction,
Kinematical cut

Pure Σ p scattering
+

31

NL-NR
A= N +NLR

E452AE452B & C

(a)

(b)

Event-selection statistics

Triggered events

452B&C

E452A

7,000,000

600,000

invariant -mass cut, vertex cut(π,K) events

700,000

60,000Eye scanningΣ p candidates
+

2,400

500

Pointing, 3D-reconstruction,
Kinematical cut

Pure Σ p scattering
+

111

31

NL-NR
A= N +NLR

E452B & C

Check the Image1An example of aΛ production event

P
K+32

P
K+πΛ
π+πΛ
π+π+

3+13DI

3+23D

1+23DIIIII

1&2

1&3

2&3

1&2

1&3

2&3

SCITIC vs. SCIFI

Picture： SCIFI > SCITIC
Clear
Low noise
Versatility：SCITIC > SCIFI
Any target material
larger H/C,
gas scintillator
polarized active target

Adjustable magnification
charm, beauty particles
cosmic observation