Staging strategy of E15 - KEKnuclpart.kek.jp/pac/1101/pdf/pac2011.pdf · E15 staging strategy E151st ~ 30kW*week 2) DISTO DATA T. Yamazaki, M. Maggiora, P. Kienle, et al, PRL 104,

M. IwasakiRIKEN Nishina Center & TITech

Staging strategy of E15

for J-PARC E15 Collaboration

2011年1月15日土曜日

K- 3He K-pp

Λ

neutron

proton

proton

π−

decay

formation

at 1 GeV/c by bothmissing & invariant mass

K- 3He -> “ pp K- ” + n

E15: KN interaction study by nuclear bound state-


E15 staging strategy E151st ~ 30kW*week



motivated by


1) Production cross sectioncan be as large as

few mb/sr in bound region!


motivated by


T. Koike, T. Harada, Phys. Rev. C80, 055208 (2009)




motivated by






2) DISTO DATA

motivated by






2) DISTO DATAT. Yamazaki, M. Maggiora, P. Kienle, et al, PRL 104, 132502 (2010)

motivated by






2) DISTO DATAT. Yamazaki, M. Maggiora, P. Kienle, et al, PRL 104, 132502 (2010)

3) Background Study

motivated by


Production cross section (KH)T. Koike, T. Harada, Phys. Rev. C80, 055208 (2009)

K-pp N,,,,

K-pp YN,,,,

K-pp total,,,,

V0 = -344 W0 = -203 MeV

K-pp N,,,,

(SGM)

K-pp total,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

V0 = -404 W0 = -213 MeV

-150 -100 -50 0 50E ( MeV )

K-pp N,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

-150 -100 -50 0 500

20

40

60

E ( MeV )

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(FINUDA)

K-pp N,,,,K-pp N

,, ,,K-pp YN,,,,

K-pp total,,,,

V0 = -292 W0 = -107 MeV(YA)B( N) = 0.7

B(YN) = 0.2

1B( N) = 0.11

2

K-pp N,,,,

K-pp N,,,,K-pp YN,,,,

K-pp total,,,,

V0 = -237 W0 = -128 MeVB( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

0

20

40

60

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(DHW)

DHW: A. Dote, T. Hyodo, and W. Weise, Nucl. Phys. A804, 197 (2008); Phys. Rev. C79, 014003 (2009).

YA: T. Yamazaki and Y. Akaishi, Phys. Lett. B535, 70 (2002); Proc. Jpn. Academy, Series B 83, 144 (2007)

SGM: N.V. Shevchenko, A. Gal, and J. Mares, Phys. Rev. Lett. 98, 082301 (2007);N.V. Shevchenko, A. Gal, J. Mares, and J. Revai, Phys. Rev. C76, 044004 (2007).

˘

˘

FINUDA: M. Agnello et al., Phys. Rev. Lett. 94, 212303 (2005).

3He (K-, n) X @ 1 GeV/c Excluding K- escape process



K-pp N,,,,

K-pp YN,,,,

K-pp total,,,,

V0 = -344 W0 = -203 MeV

K-pp N,,,,

(SGM)

K-pp total,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

V0 = -404 W0 = -213 MeV

-150 -100 -50 0 50E ( MeV )

K-pp N,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

-150 -100 -50 0 500

20

40

60

E ( MeV )

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(FINUDA)

K-pp N,,,,K-pp N

,, ,,K-pp YN,,,,

K-pp total,,,,

V0 = -292 W0 = -107 MeV(YA)B( N) = 0.7

B(YN) = 0.2

1B( N) = 0.11

2

K-pp N,,,,


K-pp total,,,,

V0 = -237 W0 = -128 MeVB( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

0

20

40

60

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(DHW)

DHW: A. Dote, T. Hyodo, and W. Weise, Nucl. Phys. A804, 197 (2008); Phys. Rev. C79, 014003 (2009).

YA: T. Yamazaki and Y. Akaishi, Phys. Lett. B535, 70 (2002); Proc. Jpn. Academy, Series B 83, 144 (2007)

SGM: N.V. Shevchenko, A. Gal, and J. Mares, Phys. Rev. Lett. 98, 082301 (2007);N.V. Shevchenko, A. Gal, J. Mares, and J. Revai, Phys. Rev. C76, 044004 (2007).

˘

˘

FINUDA: M. Agnello et al., Phys. Rev. Lett. 94, 212303 (2005).


few mb/sr in bound region!cf. 10 μb/sr assumed in prop.



K-pp N,,,,

K-pp YN,,,,

K-pp total,,,,

V0 = -344 W0 = -203 MeV

K-pp N,,,,

(SGM)

K-pp total,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

V0 = -404 W0 = -213 MeV

-150 -100 -50 0 50E ( MeV )

K-pp N,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

-150 -100 -50 0 500

20

40

60

E ( MeV )

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(FINUDA)

K-pp N,,,,K-pp N

,, ,,K-pp YN,,,,

K-pp total,,,,

V0 = -292 W0 = -107 MeV(YA)B( N) = 0.7

B(YN) = 0.2

1B( N) = 0.11

2

K-pp N,,,,


K-pp total,,,,

V0 = -237 W0 = -128 MeVB( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

0

20

40

60

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(DHW)





K-pp N,,,,

K-pp YN,,,,

K-pp total,,,,

V0 = -344 W0 = -203 MeV

K-pp N,,,,

(SGM)

K-pp total,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

V0 = -404 W0 = -213 MeV

-150 -100 -50 0 50E ( MeV )

K-pp N,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

-150 -100 -50 0 500

20

40

60

E ( MeV )

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(FINUDA)

K-pp N,,,,K-pp N

,, ,,K-pp YN,,,,

K-pp total,,,,

V0 = -292 W0 = -107 MeV(YA)B( N) = 0.7

B(YN) = 0.2

1B( N) = 0.11

2

K-pp N,,,,


K-pp total,,,,

V0 = -237 W0 = -128 MeVB( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

0

20

40

60

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(DHW)



K-pp N,,,,

K-pp YN,,,,

K-pp total,,,,

V0 = -344 W0 = -203 MeV

K-pp N,,,,

(SGM)

K-pp total,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

V0 = -404 W0 = -213 MeV

-150 -100 -50 0 50E ( MeV )

K-pp N,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

-150 -100 -50 0 500

20

40

60

E ( MeV )

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(FINUDA)

K-pp N,,,,K-pp N

,, ,,K-pp YN,,,,

K-pp total,,,,

V0 = -292 W0 = -107 MeV(YA)B( N) = 0.7

B(YN) = 0.2

1B( N) = 0.11

2

K-pp N,,,,


K-pp total,,,,

V0 = -237 W0 = -128 MeVB( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

0

20

40

60

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(DHW)

limiting to nYN final states1mb/sr!~>


exclusive pp → K+Λp at Tp = 2.85 GeV

BK~100MeV and ΓK~100MeV

T. Yamazaki, M. Maggiora, P. Kienle, et al, PRL 104, 132502 (2010)

DISTO DATA


KH vs DISTO

K-pp N,,,,

K-pp YN,,,,

K-pp total,,,,

V0 = -344 W0 = -203 MeV

K-pp N,,,,

(SGM)

K-pp total,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

V0 = -404 W0 = -213 MeV

-150 -100 -50 0 50E ( MeV )

K-pp N,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

-150 -100 -50 0 500

20

40

60

E ( MeV )

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(FINUDA)

K-pp N,,,,

K-pp N,, ,,K-pp YN,,,,

K-pp total,,,,

V0 = -292 W0 = -107 MeV(YA)B( N) = 0.7

B(YN) = 0.2

1B( N) = 0.11

2

K-pp N,,,,


K-pp total,,,,

V0 = -237 W0 = -128 MeVB( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

0

20

40

60

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(DHW)


KH vs DISTO

K-pp N,,,,

K-pp YN,,,,

K-pp total,,,,

V0 = -344 W0 = -203 MeV

K-pp N,,,,

(SGM)

K-pp total,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

V0 = -404 W0 = -213 MeV

-150 -100 -50 0 50E ( MeV )

K-pp N,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

-150 -100 -50 0 500

20

40

60

E ( MeV )

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(FINUDA)

K-pp N,,,,


K-pp total,,,,

V0 = -292 W0 = -107 MeV(YA)B( N) = 0.7

B(YN) = 0.2

1B( N) = 0.11

2

K-pp N,,,,


K-pp total,,,,

V0 = -237 W0 = -128 MeVB( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

0

20

40

60

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(DHW)

-150 -100 -50 0 50E ( MeV )

-150 -100 -50 0 500

20

40

60

E ( MeV )

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(FINUDA)

K-pp total,,,,

V0 = -292 W0 = -107 MeV(YA)B( N) = 0.7

B(YN) = 0.2

1B( N) = 0.11

2

,,

K-pp total,,,,

V0 = -237 W0 = -128 MeVB( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

0

20

40

60

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(DHW)

K-pp N,,,,DISTO K-pp N,,,,DISTO

K-pp N,,,,DISTOK-pp N,,,,DISTO

DISTO


KH vs DISTO

K-pp N,,,,

K-pp YN,,,,

K-pp total,,,,

V0 = -344 W0 = -203 MeV

K-pp N,,,,

(SGM)

K-pp total,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

V0 = -404 W0 = -213 MeV

-150 -100 -50 0 50E ( MeV )

K-pp N,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

-150 -100 -50 0 500

20

40

60

E ( MeV )

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(FINUDA)

K-pp N,,,,


K-pp total,,,,

V0 = -292 W0 = -107 MeV(YA)B( N) = 0.7

B(YN) = 0.2

1B( N) = 0.11

2

K-pp N,,,,


K-pp total,,,,

V0 = -237 W0 = -128 MeVB( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

0

20

40

60

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(DHW)

-150 -100 -50 0 50E ( MeV )

-150 -100 -50 0 500

20

40

60

E ( MeV )

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(FINUDA)

K-pp total,,,,

V0 = -292 W0 = -107 MeV(YA)B( N) = 0.7

B(YN) = 0.2

1B( N) = 0.11

2

,,

K-pp total,,,,

V0 = -237 W0 = -128 MeVB( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

0

20

40

60

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(DHW)



DISTO

- does not fit in KH scheme


- only for Λp decay ch.private communication


KH vs DISTO

K-pp N,,,,

K-pp YN,,,,

K-pp total,,,,

V0 = -344 W0 = -203 MeV

K-pp N,,,,

(SGM)

K-pp total,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

V0 = -404 W0 = -213 MeV

-150 -100 -50 0 50E ( MeV )

K-pp N,,,,

B( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

-150 -100 -50 0 500

20

40

60

E ( MeV )

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(FINUDA)

K-pp N,,,,


K-pp total,,,,

V0 = -292 W0 = -107 MeV(YA)B( N) = 0.7

B(YN) = 0.2

1B( N) = 0.11

2

K-pp N,,,,


K-pp total,,,,

V0 = -237 W0 = -128 MeVB( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

0

20

40

60

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(DHW)

-150 -100 -50 0 50E ( MeV )

-150 -100 -50 0 500

20

40

60

E ( MeV )

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(FINUDA)

K-pp total,,,,

V0 = -292 W0 = -107 MeV(YA)B( N) = 0.7

B(YN) = 0.2

1B( N) = 0.11

2

,,

K-pp total,,,,

V0 = -237 W0 = -128 MeVB( N) = 0.7 B(YN) = 0.2

1B( N) = 0.11

2

0

20

40

60

d2/d

ndE n

( µ

b/(s

r. MeV

) )

(DHW)



DISTO

- does not fit in KH scheme


- only for Λp decay ch.private communication

easy to observe,if dσ/dΩ 1mb/sr~>and Λp decay channel

( n + Λp final state )


Neutron missing mass spectra @ 30kW*week

simulated by T. Hiraiwa

2000 2200 2400 2600 2800 3000]2c,n) [MeV/-He(K3missing mass of

0

100

200

300

400

500

coun

ts

Expected yield for 30 kW. week

incident beampp -K p (100%)

conv.2NR + N FSI2NR +

relative yields of background

components are unknown

equal yields assumed

3He(K-,n) p : fully reconstructed

acceptance

600




Assume DISTO like data, BK~100MeV and ΓK~100MeV

dσ/dΩθ=0 = 1 mb/srBR(Λp) = 100 %

for simplicity

p3He

nK-

CDS

NC

"Kpp"

signal


0

100

200

300

400

500

coun

ts








acceptance

600




Assume DISTO like data, BK~100MeV and ΓK~100MeV

dσ/dΩθ=0 = 1 mb/srBR(Λp) = 100 %

for simplicity

p3He

nK-

CDS

NC

"Kpp"

signal


0

100

200

300

400

500

coun

ts








acceptance

600

2NR initiated reactions

p3He

n

K-CDS

NCσ ~ 10 mb each

backgrounds


-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q

In-flight Kinematics

p3HenK-

kinematical boundary

3-body Phase Space (Dalitz's plot) at CM

Λpn event distribution on Phase Space

simulated by T. Hiraiwa2011年1月15日土曜日

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q

CDS Acceptance

p3HenK-


CDSp in CDS(p )

CDS Acceptance


p in CDSn in NC

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q

CDS & NC Acceptance

p3HenK-


CDS

NC

CDS & NC Acceptance


on 3-body Phase Space (Dalitz's plot) at CM

p in CDSn in NC

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

(Tp - Tn ) / 3Q

T /

Q

CDS & NC Acceptance

Background? Two Nucleon Reaction and FSI (Σ-Λ conversion)


p3He

nK-

or

p3He

n

K-

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q

on 3-body Phase Space (Dalitz's plot) at CM2NR and conversion



multi-step PWIA


p3He

nK-

or

p3He

n

K-

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q




multi-step PWIA

1st step


p3He

nK-

or

p3He

n

K-

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q




multi-step PWIA

1st step

2nd step


p3He

nK-

or

p3He

n

K-

n

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q


CDS

CDS

p3He

nK-

or

p3He

n

K-

n

p in CDS(p )



multi-step PWIA


p3He

nK-

CDS

NC

p3He

n

K-CDS

NCor

p in CDSn in NC

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q




multi-step PWIA


p3He

nK-

CDS

NCon 3-body Phase Space (Dalitz's plot) at CM2NR and conversion

0

0.2

0.4

0.6

0.8

1

p in CDSn in NC

-0.6 -0.4 -0.2 0 0.2 0.4 0.6

(Tp - Tn ) / 3Q

T /

Q

p3He

n

K-CDS

NCor

p3He

nK-

CDS

NC

"Kpp"

signal

Background? vs signal (ratio arbitrary)Two Nucleon Reaction and FSI (Σ-Λ conversion)


multi-step PWIA


Is two nucleon reaction possible?in in-flight kinematics @ 1GeV/c

De Broglie wave length @ 1 GeV/c ~ 1.2 fm<

Nucleon distance ~ 1.5 fm

Not very likely...

although 2NR process should be examined on

cf.

1) nucleon or hyperon scattering2) Σ→Λ conversion

Two successive reaction after KNN

Note: Simple KNN channel excluded: Because it is easy to discriminate

T. Kishimoto et al., Prog. Theor. Phys. 118 (2007) 181

2NR not

seen!

by reducing the trigger level.


π+p

π−

preliminary

~2800 Λ σmass =3.5MeV/c2

preliminary

Present?

missing: transportation ofSW Magnet and NC


E151st ~ 30kW*week (2% in terms of proton on target)

E15 staging strategy

E15 approved = 1500kW*week (@ Pt equiv.)apparatus preparation is ready

not easy to realize

1) to know the background processes 2) to evaluate the realistic beam time for E15full

3) present an information of the KN interaction 3He(K-, n) spectrum below KN threshold4) a hint of signal in Λ + p + n final states

--

E151st realize before long shutdown in 2012


E151st ~ 30kW*week (2% in terms of proton on target)

E15 staging strategy

divide into 3 periods

E15 approved = 1500kW*week (@ Pt equiv.)apparatus preparation is ready

not easy to realize

1) to know the background processes 2) to evaluate the realistic beam time for E15full

3) present an information of the KN interaction 3He(K-, n) spectrum below KN threshold4) a hint of signal in Λ + p + n final states

--

E151st realize before long shutdown in 2012


J-PARC E15 Collaborationhttp://ag.riken.jp/J-PARC/collaboration/


http://ag.riken.jp/J-PARC/collaboration/

http://ag.riken.jp/J-PARC/collaboration/

Thank you for attention!


spare


K1.8BR with Pt (@50% loss)

E17 ~ 10kW*week

E151st ~ 30kW*week (first stage)cf. 1500kW*week (E15 full @ Pt equiv.)

E31 ~ 180kW*week

KN by x-ray via K- 3He

KN by bound state via K- 3He

Λ(1405) via K- d

> 2kW?

> 10kW?> 100kW?

> 20~40kW?

required power

All K incident experiments: Present Duty Factor will be OK up to few 10th of kW


Signal can be easily discriminated from signal in both FSI cases !

1) nucleon or hyperon scattering2) Σ→Λ conversion

Two successive reaction after KNN

Note: Simple KNN channel excluded: Because it is easy to discriminate


p in CDSn in NC

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q

CDS & NC Acceptance

p3HenK-


CDS

NC

Can we extend the detection capability?


p in CDSn in NC

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q

CDS & NC Acceptance with one proton missing

p3HenK-


CDS

NC

p missing from CDS



p3HenK-

CDS

NC

p missing from CDS

p3He

nK-

CDS

NC

"Kpp"

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q

"Kpp" 3-body Phase Space (Dalitz's plot) at CM


BK~100MeV, ΓK~100MeV(like DISTO data)


-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q

"Kpp" with one proton missing3-body Phase Space (Dalitz's plot) at CM

p3HenK-

CDS

NC

p missing from CDS

p3He

nK-

CDS

NC

"Kpp"

p missing from CDS


BK~100MeV, ΓK~100MeV(like DISTO data)


Λpn final state selection by CDS & NCWhat happens if we miss other particles?

Other processes can be clearly

separated!


other than Λpn

Missing Energy [MeV]0 200 400 600 8000

50

100

150

200

250

coun

ts (a

.u.)

relative yields of each components

are unknown

missingmissing

QF-

pn final state

0pn final state

+


•Efficiency (NC eff. Is not included.)-‐3body phase space 0.079 % (all detected)

“Kpp”(B=100MeV Γ=100MeV) 0.042 % (all detected)0.098 % (one proton missing)

0.12% (one proton missing)

Improvement by one proton missing

Λpn / Σ0pn still be separated

x 2 improvement

Are they perfect?

QF-Y production also separated


•Missing proton resoluOon: 28.4 ±0.3 MeV/c2

but partial overlap with pπ missing

=X = N

NX = NX = NX =

]2cpn) [MeV/-, -Missing Mass of 3He(K600 800 1000 1200 1400 1600 1800

coun

ts (a

.u.)

0

1000

2000

3000

4000

5000

6000relative yields of each


missingp

p missing

p missing p missing



on 3-body Phase Space (Dalitz's plot) at CM

p in CDSn in NC

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

(Tp - Tn ) / 3Q

T /

Q

CDS & NC Acceptance



p3He

nK-

CDS

NCon 3-body Phase Space (Dalitz's plot) at CM

p in CDSn in NC

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q

2NR and conversion

s

or

p3He

n

K-CDS

NCs

s

s



multi-step PWIA


p3He

nK-

CDS


p in CDSn in NC

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q

2NR and conversion

s

or

p3He

n

K-CDS

NCs

s

s



multi-step PWIA

1st step


p3He

nK-

CDS


p in CDSn in NC

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q

2NR and conversion

s

or

p3He

n

K-CDS

NCs

s

s



multi-step PWIA

1st step

2nd step


p3He

nK-

CDS


p in CDSn in NC

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q

2NR and conversion

s

or

p3He

n

K-CDS

NCs

s

s



multi-step PWIA


p3He

nK-

CDS


p in CDSn in NC

-0.6 -0.4 -0.2 0 0.2 0.4 0.60

0.2

0.4

0.6

0.8

1

T /

Q

(Tp - Tn ) / 3Q

2NR and conversion

s

or

p3He

n

K-CDS

NCs

s

s



multi-step PWIA


p3He

nK-

CDS


p in CDSn in NC

-0.6 -0.4 -0.2 0 0.2 0.4 0.6

(Tp - Tn ) / 3Q

0

0.2

0.4

0.6

0.8

1

T /

Q

2NR and conversion

s

or

p3He

n

K-CDS

NCs

s

s

p3He

nK-

CDS

NC

"Kpp"

signal signal

Background? vs signal (ratio arbitrary)Two Nucleon Reaction and FSI (Σ-Λ conversion)


multi-step PWIA


• Yield = Nkaon x t x dσ/dΩ(θ=0) x r x R x A x e x ε

–Nkaon : kaon per spill → 300k/spill (30 kW operaOon)

–t : target → 0.08 [g/cm3] / 3 [g/mol] x 6.02 x 1023 [mol-‐1] x 9.3 [cm] ~ 1.4 x 1023 [cm-‐2] –dσ/dΩ (@ θ = 0) → 3 [mb/sr] –r : branching raOo (Λ → π-‐p) → 0.63–R : “Kpp” decay branch → Br(Λp) + Br(Σ0p) ~ 1–A : NC acceptance → 12 [msr] –e : NC efficiency → 0.3

–ε : overall efficiency (trigger, detector, ana., etc) → 0.7• 2.1 x 104 signals on missing mass spectrum (by 1 week run)

Estimated yield by one proton missing

PLB 652(2007)262-268PR C 80,055208(2009)

(Λp + Σ0p branch)


Staging strategy of E15 - KEKnuclpart.kek.jp/pac/1101/pdf/pac2011.pdf · E15 staging strategy E151st ~ 30kW*week 2) DISTO DATA T. Yamazaki, M. Maggiora, P. Kienle, et al, PRL 104,

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