jasmin results and plans ○ shun sekimoto , h. yashima (kyoto university)

JASMIN Results and Plans

○ Shun SEKIMOTO, H. YASHIMA (Kyoto University)H. MATSUMURA, A. TOYODA (KEK) K. OISHI,(Shimizu Corporation)

N. MATSUDA, Y. KASUGAI, Y. SAKAMOTO, H. NAKASHIMA (JAEA) D. BOEHNLEIN, G. LAUTEN, A. LEVELING, N. MOKHOV, K. VAZIRI (FNAL)

JASMIN (Japanese-American Study of Muon Interactions

and Neutron detection) Collaboration

JASMIN Results and Plans

JASMIN (Japanese-American Study of Muon Interactions

and Neutron detection) Collaboration

-Contents-1. Chemical Analysis of Gas at AP0 target station 2. Chemical Analysis of Cooling water from AP0 and NuMI3. Activation experiments in NuMI for muon-induced nuclear reactions

1. Chemical Analysis of Gas at AP0 target station # Collection of radioactive aerosols from the AP0 target vault using Impactor method

# Separation of radioactive aerosols into several samples according to particulate size ranging from 0.056 to 10 m

target room

Air gap

120 GeVproton

Inconel target

Concrete shielding

Iron shielding

Anti-proton target station

(AP0)→

Ave. beam current: 250-290 nA

To know particle size of those radioactive aerosols →For the radiation control purposes, especially for evaluating the internal exposure of the workers.

Target room120 GeVproton

target

Concrete shielding

Iron shielding

Impactor

Flow meter

Pump

Experimental (Aerosol-sampling) (3h sampling)

Gas/ aerosol-sampling device↓

Filter holder

Experimental (Aerosol-sampling)

Results: 14 nuclides→Be-7, Na-22, Na-24, Sc-46, Sc-47, V-48, Cr-51, Mn-54, Co-56, Co-57, Co-58, Co-60, Au-196, Au-198

# Separation of radioactive aerosols into several samples with different particle size

←Impactor10 stages for particles with 0.056 to 10 m diameter# Collected on Aluminum foil # 30 L of air /min of flow rate# 3 h-sampling (≈ 5.4 m3 of air in total) # gamma-ray spectrometry

10-7 10-6 10-50

1

2

3

4[103]

Particle diameter (dp, m)

(dA

0/dl

ndp)

7Be aerosol fitted

　　 GMD 1.6μ m　　 GSD 2.3

Be-7(T1/2: 53.3 d)

GMD: Geometric mean diameter

Results: Particle size distribution

10-1 100 101 102 10310-1

100

101Discussion: Half life vs. particle size distribution

Half-life (day)

GM

D (

μm

)

Na-24

Au-198Sc-47Au-196

V-48Cr-51Be-7Co-58Co-56Sc-46Co-57Mn-54Na-22Co-60

→From the correlation, growing up of aerosols in the accelerator target room could be discussed.

10-1 100 101 102 103

1

2

3Half life vs. particle size distribution (target room)

Half-life (day)

GM

D (

μm

)● 　 Feb_2010○ 　 Dec_2010

Na-24

Sc-44mAu-198Sc-47Mn-52Au-196

V-48Cr-51Be-7Co-58Co-56Sc-46Co-57Mn-54

0 20 40 60 80 100

0 20 40 60 80 100

NuMI Target

NuMI Horn1

NuMI Horn2

NuMI Decay pipe

NuMI Absorber

Pbar Collection lens

Pbar Pulse magnet

Pbar Dump

Colloid (>3 nm)Ion

Colloid formation for Be-7 in the cooling waters [%]

Dec2010

Sep2011Dec2010Feb2010




Sep2011Dec2010

Sep2011Dec2010

Sep2011Dec2010

Sep2011Dec2010

Study　of　colloid　formation　in　cooling-waters(Experiments　in　Feb.　2010,　Dec.　2010,　and　Sep.　2011)

Five　Major　IMPORTANT　Results

Filter　&　Ion-exchange

Filter

Colloid

Ion

In　case　of　Be-7 Equipped water purification system

(1)　radiocolloid　formation　rates　in　the　cooling　waters　are　significantly　high,(2)　radiocolloid　formation　rate　depends　on　the　cooling　water　system,(3)　remaining　rate　of　Be-7　in　the　cooling-water　depend　on　water　purification　system,(4)　radiocolloid　takes　positive　charge,(5)　weak　retention　of　colloid　with　cation-exchange　resin　was　observed.Remaining rate in

cooling-water

0.002-0.05%

~5%

NuMI

Pbar

Study　of　muon-induced　nuclear　reactions　at　NuMIThree　Major　IMPORTANT　Results(1)　split　muon　beam　came　into　the　NuMI　absorber　hall,(2)　nucleus　excitation　by　muon　is　similar　to　by　real　photon　(see　Figs.1　and　2),(3)　a　reaction　channel　that　have　not　been　observed　in　bremsstrahlung-induced　reaction　was　observed　in　muon-induced　Au　spallation　(see　Fig.　3).

0 5 10 15 20 25 30 35 40 450

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

Mass difference,

v [(

MeV

/nuc

l.)1/

2]

NuMI Absorber room, Cu-2 (at peak)

E0=600-1100 MeV, Haba et al.

400 GeV, Cole and Porile29 GeV, Porile and Tanaka28 GeV, Cumming et al.3 GeV, Crespo et al.810 MeV, Cumming et al.700 MeV, Crespo et al.600 MeV, Lagarde-Simonoff et al.150 MeV, Lagarde-Simonoff et al.

Muon

Bremsstrahlung

Proton

Cu　target

10-1 100 101 10210-2

10-1

100

Kinetic energy (GeV)

Slop

e of

mas

s yi

eld

curv

e P

alcove-1

alcove-2photon

hadron

0 20 40 60 80 100 120 140 160 180 20010-38

10-37

10-36

10-35

10-34

10-33

10-32

10-31

Product mass number

Pro

du

ctio

n r

ate

s

Au　target

alcove0-peak

alcove0-center

alcove1

alcove2

Cu　target

Cu　target

Deposit　energy

　into　target　nucleus

=

Velocity　of　nucleus　

at　1st　step　of　nuclear　reaction

=

Mass　yield　distribution　in　Au　target

Fig.2

Fig.1

Fig.3

a　reaction　channel　that　have　not　been　observed　in　bremsstrahlung-induced　

reaction

similar　to　by　real　photon

similar　to　by　real　photon

10-7 10-6 10-50

1

2

3

4[103](N

0/dl

ndp)


24Na aerosol fitted

GMD 470nm, GSD 2.57

10-7 10-6 10-50

0.5

1

1.5

[104]

(N0/

dlnd

p)


198Au aerosol fitted

GMD 1.22μ mGSD 1.80

10-7 10-6 10-50

100

200

300

400

(N0/

dlnd

p)


47Sc aerosolfitted


[×104]

Na-2414.96 h

Au-1982.696 d

Sc-473.35 d

10-7 10-6 10-50

200

400

600

800

(N0/

dlnd

p)


196Au aerosolfitted


Au-1966.183 d

(dA

0/d

lnd p

)

10-7 10-6 10-50

200

400

600(N

0/dl

ndp)

Particle diameter (d p, m)

48V aerosolfitted


10-7 10-6 10-50

200

400

600

(N0/

dlnd

p)


51Cr aerosolfitted


V-4815.97 d

Cr-5127.7 d

(dA

0/d

lnd p

)

10-7 10-6 10-50

1

2[103]

(N0/

dlnd

p)


56Co aerosol fitted


Co-5677.26 d

10-7 10-6 10-50

1

2

3

4

5[103]

(N0/

dlnd

p)


58Co aerosol fitted


Co-5870.86 d


10-7 10-6 10-50

200

400

600(N

0/dl

ndp)


46Sc aerosolfitted


Sc-4683.82 d

(dA

0/d

lnd p

)


10-7 10-6 10-50

1

2

3[103]

(N0/

dlnd

p)


54Mn aerosol fitted


10-7 10-6 10-50

1

2

3[104]

(N0/

dlnd

p)


57Co aerosol fitted

GMD 2.24umGSD 2.02

Co-57271.8 d

Mn-54312.2 d

10-7 10-6 10-50

100

200

(N0/

dlnd

p)


22Na aerosol fitted

GMD 2.59 umGSD 2.12

Na-222.603 y

Restart of AP0-operation → サプリング : 2010.2月

Na-24Au-198Sc-47Au-196V-48Cr-51Be-7Co-58Co-56Sc-46Co-57Mn-54Na-22Co-60





Growing up of aerosols

Discussion: Half life vs. particle size distribution






Growing up of aerosols

Discussion: Half life vs. particle size distributionRestart of AP0-operation →6 month→ Aerosol-sampling

10-7 10-6 10-50

100

200(N

0/dl

ndp)


60Co aerosol fitted

GMD 2.55 umGSD 2.09

Co-605.272 y

jasmin results and plans ○ shun sekimoto , h. yashima (kyoto university)

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