Measurement Study of Metal Melting Liquid Scintillator Concentration

(1)

Vol. 63, No. 9, September 2013, pp. 1019∼1022

New Physics: Sae Mulli, DOI: 10.3938/NPSM.63.1019

Measurement Study of Metal Melting Liquid Scintillator Concentration

Sun Heang So · Kyung Kwang Joo ^∗

Institute for Universe & Elementary Particles, Department of Physics, Chonnam National University, Gwangju 500-757, Korea

(Received 9 July 2013 : revised 15 July 2013 : accepted 11 September 2013)

For detecting neutrinos from a nuclear power plant, we use the inverse-beta-decay reaction which a positron and a neutron after a neutrino collision with a target. We melt Gd in a liquid scintillator in order to extend the neutron-capture cross section area. For a neutrino experiment to be successful, know the exact Gd concentration and maintain that concentration are important. To do that, we measure the Gd concentration by EDTA (Ethylene Diamine Tetra Acetic acid) and PGAA (Prompt gamma neutron activation analysis) methods and use standard samples for calibration.

We confirmed that the measured Ga concentration well compares with the converted concentration value from experimental data.

PACS numbers: 13.15.+g

Keywords: Liquid Scintillator, Gd, Concentration, LAB, EDTA titration

8 c´ o Ó ÞA 0 u = k V È° Ë Ñ ß e È û s Ú Ó Þu 8 ý Ò Þy ¢ ¤X N Ë R w ì Å

Ð` 9 á ¥ · ® £# Ü ¢ 9

∗

z @ / < Æ § Ó ü t o < Æõ Ä ºÅ Ò èw n ½ ¨ è, F g Å Ò 500-757

(2013¸ 7 Z 4 9{ 9 ~ Ã Î6 £ §, 2013¸ 7 Z 4 15{ 9 Ã º& ñ : r ~ Ã Î6 £ §, 2013¸ 9 Z 4 11{ 9 > F S X & ñ )

"

é

¶ \ " f ~ ½ ÓØ ¦ ÷ & H × æ$ í p \ ¦ Ø ¦ l 0 AK × æ$ í p ³ ð& h \ Ø æ[ t ô Ç Ê ê ª ü < × æ$ í \ ¦ Ò q t

$ í

H % i Z ì ø Í6 £ x` ¦ s 6 x ½ + É Ã º e . × æ$ í í S \ í ß ê ø Í é ß & h ` ¦ ß ¼> l 0 AK Ó o^ $ 3 F g Ø ¦6 xÓ o

\

[ t o ³ o u` ¦ 6 x K ô Ç . $ í / B N& h z ´+ « >` ¦ 0 AK " f H [ t o ³ o u _ g Ë > s Â ÒÄ » & ³ © s { 9 # Q t · ú §

¦ 0 l x ¸ { 9 & ñ K ¦ [ t o ³ o u _ 0 l x ¸\ ¦ & ñ S X y H כ É r × æ כ ¹ . s \ ¦ 0 AK : r z ´+ « >\ " f H EDTA & h & ñ Z O õ PGAA ~ ½ ÓZ O ` ¦ s 6 x # 0 l x ¸\ ¦ 8 £ ¤& ñ % i ¦ ³ ðï r6 xÓ o` ¦ s 6 x K " f Õ ª 0 l x ¸ ° ú כ` ¦ Ð

&

ñ % i . s X O > Ð& ñ ) a [ t o ³ o u _ 0 l x ¸ ° ú כ` ¦ z ´+ « > X <s ' \ _ K ¨ 8 í ß ) a 0 l x ¸ ° ú כõ q §Ù þ ¡` ¦ M :

¸ ú

{ 9 u H כ ` ¦ S X ½ + É Ã º e % 3 .

PACS numbers: 13.15.+g

Keywords: Ó o^ $ 3 F g Ø ¦6 xÓ o, [ t o ³ o u, 0 l x ¸, + þ A· ú ~ ´ $ H $ , EDTA & h & ñ

∗

E-mail: [email protected]

1019

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1020 New Physics: Sae Mulli, Vol. 63, No. 9, September 2013

I. ô v ÚP Õ ÛT Ó ÞA 0c Ü R Ò Å] k ù° oû m Ç Ö Ö M m u

= kV È° Ë Ñß e È û s Ú Ó Þu

×

æ$ í p Ø ¦` ¦ 0 AK Ó o^ $ 3 F g Ø ¦6 xÓ o (Liquid Scintillator, LS)` ¦ 6 x ¦ e [1]. : r z ´+ « >\ " f H + þ

A· ú ~ ´ $ H $ (Linear Alkyl Benzene, C

n

H

2n+1

-C

6

H

5

, n = 10 ∼ 13, LAB)` ¦ l ì ø ÍÜ ¼ Ð Ó o^ $ 3 F g Ø ¦ 6 xÓ o` ¦ Ò re ¦ Ð

6 x % i . + þ A· ú ~ ´ $ H $ É r ² D G ? /\ Ò q tí ß \ O ^ e # Q ½ ¨

l ~ 1 ¦, µ 1 Ï o& h ¸ 130

^◦

C Ð Z } î ß . o < Æ& h ½ ¨

¸\ $ H $ ¦o \ ¦ t ¦ e l M :ë H \ + þ AF g$ í ` ¦ ` (# Q y n C

~

½ ÓØ ¦ | ¾ Ó ¸ PC (Pseudocumene, C

9

H

12

) ü < q §K ¸ + 't t

· ú § H . ± ú É r f ¨F g ¸ ° ú כõ | y û Z o \ ¦ t ¦ e Ü

¼ 9 2 ;¨ 8 â & h © & h ` ¦ t ¦ e [2, 3]. y n C` ¦ ? /l 0

Aô Ç $ 3 F g ^ Ð 2,5-diphenyloxazole (PPO, C

¹⁵

H

11

NO)

\

¦ 6 xÙ þ ¡ . ¢ ¸ô Ç © ` ¦ â l 0 AK 1,4,-bis(2- methylstyryl)-benzene (bis-MSB, C

12

H

16

N

2

O

2

)\ ¦ '

Ù þ

¡ . z ´+ « >\ H 8 £ ¤& ñ Ò re ¦ \ H 3 g/` _ PPOü < 30 mg/`_ bis-MSB\ ¦ 0 l q # " f 6 x % i .

×

æ$ í p Ø ¦` ¦ 0 AK % i Z (ν

e

+ ρ → e

⁺

+ n) Ô æ õ

ì ø Í6 £ x` ¦ s 6 x ½ + É â Ä º s ì ø Í6 £ x \ " f µ 1 ÏÒ q t H × æ$ í

\

¦ ¸ ú í S \ H כ s × æ כ ¹ . × æ$ í í S \ é ß & h ` ¦ ß

¼> l 0 AK [ t o ³ o u` ¦ 6 x K ô Ç Ó o^ $ 3 F g Ø ¦6 xÓ o (Gadolinium-loaded Liquid Scintillator, GdLS)` ¦ 6 x ô

Ç . [ t o ³ o u` ¦ + þ A· ú ~ ´ $ H $ \ 6 x K r v l 0 AK " f Ä » l

o ç ß × ¼(Ligand)\ ¦ ½ + Ër & Ä »l F K5 Å q (organometal- lic)` ¦ ë ß × ¼ H ~ ½ ÓZ O ` ¦ 6 xÙ þ ¡ . Ä »l o ç ß × ¼ H F K5 Å q õ 6 x l

6 x B \ 0 l q H Ó ü t| 9 Ð : r z ´+ « >\ " f H Ø Ô4 ¤z ´í ß (car- boxylic acid) × æ TMHA (3,5,5-trimethylhexanoic acid)` ¦ 6 x % i . TMHA\ ¦ 6 x # [ t o ³ o u` ¦ 6 x K

ô Ç Ó o^ $ 3 F g Ø ¦6 xÓ o_ î ß & ñ $ í , 6 x K ¸, y n C ~ ½ ÓØ ¦ | ¾ Ó 1 p x

×

æ$ í p z ´+ « >\ 9 כ ¹ô Ç $ í | 9 ` ¦ Ø æì r y ë ß 7 á ¤ r v l M : ë

H s . Ä »l F K5 Å q Gd-TMHA\ ¦ ] j ¸ H × æ oì ø Í6 £ xd

É

r 6 £ § õ ° ú .

(1) RCOOH + NH

3

·H

2

O → RCOONH

4

+ H

2

O (2) RCOONH

4

+ GdCl

3

→Gd(RCOO)

3

+ 3NH

4

Cl

(1) d É r Ø Ô4 ¤z ´í ß \ ¸m Ã º\ ¦ ' K " f × æ o r

v H ì ø Í6 £ xd s . Õ ª Ê ê (2) d \ " f H × æ or Ø Ô 4

¤z ´í ß õ GdCl

³

Ã º6 xÓ o` ¦ D ¥ ½ + Ë # Gd-TMHA Ä »l F K 5

Å

q` ¦ ½ + Ë$ í ô Ç d s . : r z ´+ « >\ " f H [ t o ³ o u` ¦ ∼0.1%

6 x K % i [4].

II. Ò Þy ¢ ¤X N Ë U ê s0 n É õ m Í + s ÇÊ Ý

1. EDTA X ì ÄX N Ë ù p § Þ X ¢ Ò Þy ¢ ¤X N Ë

+ þ A· ú ~ ´ $ H $ l ì ø Í_ Ó o^ $ 3 F g Ø ¦ 6 xÓ o ? /_ [ t o

³ o

u 0 l x ¸\ ¦ · ú l 0 AK EDTA (Ethylene Diamine Tetra Acetic acid) & h & ñ (Titration) Z O ` ¦ 6 x % i . 100 m`

Ä

»o # î \ Ð ' a× æ Ò re ¦` ¦ # î _ × æ © \ " f { 9 r6 x x & Ï @

`

¦ s 6 x K è| ¾ Ó G 2 [K 8 £ ¤& ñ \ 6 x ô Ç . íí H Ã º (ultra pure water) \ buffer solution, t r x 9 GdLS Ò re ¦` ¦ 6

x K r Ê ê Â Ó Ï @Ü ¼ Ð EDTA\ ¦ ô Ç ~ ½ ÓÖ ¦m b # Qä ¼o " f

'

a ¹ 1 Ïô Ç . Ð Ò o t r _ Ò o¾ ú s ¸ê ø ÍÒ oÜ ¼ Ð H í

H ç ß t 6 x ô Ç EDTA_ ª ` ¦ · ú [ t o ³ o u _ 0 l x ¸\ ¦

>

í ß ½ + É Ã º e . Ò re ¦ É r 1 m`\ ¦ í í H Ã º\ 6 x K r ( H X <

Ò

re ¦ _ l ï r \ [ t o ³ o u 0 l x ¸ > í ß ° ú כs ß ¼> % ò ¾ Ó

`

¦ ~ Ã Îl M :ë H \ B jÛ ¼ e ¦ Û ¼ß ¼, x & Ï @, $ Ö ¦ y y _ ~ ½ ÓZ O

`

¦ s 6 x # Ò re ¦` ¦ G 2 [ô Ç Â Òx \ ¦ 8 £ ¤& ñ K " f õ ° ú כ` ¦ q

§K Ð ¤ . B jÛ ¼e ¦ Û ¼ß ¼_ ½ © É r 5.0 m` ± 0.1 s

¦ è HF K õ è HZ } s \ ¦ ´ ú 2 X" f Ò re ¦ _ & ñ | ¾ Ó` ¦ G 2 [ Ê ê & h & ñ

% i . x & Ï @ É r s ß ¼ Ð x & Ï @\ s × ¼ (100 ∼ 1000 µ`)\ ¦

6 x # 1000 µ` Ò re ¦` ¦ G 2 [ % i . $ Ö ¦ _ â Ä º $ Ò

re ¦` ¦ { É r B jÛ ¼e ¦ Û ¼ß ¼_ Á º> \ ¦ ± p Ê ê, G 2 [ô Ç Ò r e

¦` ¦ íí H Ã º\ 6 x K r v ¦ z É r B jÛ ¼e ¦ Û ¼ß ¼_ Á º> \ ¦ F

" f Õ ª Á º> s ü < x 9 ¸ (0.86 g/m`, 20

^◦

C)\ ¦ s 6 x K

"

f 0 l x ¸\ ¦ > í ß % i . s â Ä º B jÛ ¼e ¦ Û ¼ß ¼\ ³ ð \ z

É r Ò re ¦ _ Á º> \ ¦ ] jü @r v ¦ [ t o ³ o u _ 0 l x ¸\ ¦ > í

ß ½ + É Ã º e . Table 1 É r s [ j t ~ ½ ÓZ O Ü ¼ Ð EDTA & h

&

ñ ` ¦ ô Ç õ \ ¦ Ð# ï r .

2. »Ç U Ø Ó Þu ù p § T Ó Þ X ¢ R w

EDTA ~ ½ ÓZ O É r Ò re ¦ _ 0 l x ¸ o\ @ /ô Ç & ñ Ð\ ¦ Å Òt ë

ß Â Òx 8 £ ¤& ñ _ Ô ¦¢ - a $ í \ " f ¸ H ¸ Ð K ] X @ /& h

0 l x ¸\ ¦ & ñ S X y H כ É r # Q§ > . " f : r z ´+ « >\ " f

H 0 l x ¸\ ¦ & ñ S X y · ú ¦ e H ³ ðï r 6 xÓ o` ¦ ½ ¨{ 9 K " f & h & ñ

`

¦ ô Ç Ê ê Ð& ñ H ~ ½ ÓZ O ` ¦ 6 x % i . 1%, 2%, 3% 0 l x ¸ _

³ ðï r 6 xÓ o` ¦ 6 x % i ¦ Õ ª & ñ x 9 ¸ H Table 2 \

?

/% 3 . [ j & h ` ¦ ½ ¨ô Ç Ê ê þ j è 5 p xZ O ` ¦ s 6 x # [ j & h

`

¦ e ± H þ j& h _ f ` ¦ ¹ 1 Ô ¤ [5]. Fig. 1 É r ] X @ /0 l x ¸\ ¦ { 9

§ 4 ° ú כÜ ¼ Ð K " f EDTA & h & ñ Ê ê_ õ ° ú כ` ¦ ½ ¨ô Ç [ j & h õ

þ j& h _ f ` ¦ > í ß K " f Õ ª 2 ; Õ ªA á Ô\ ¦ Ð# ï r . y y

B jÛ ¼e ¦ Û ¼ß ¼ (volume), x & Ï @ (pipette), $ Ö ¦ (mass)

â

Ä º\ ¦ Õ ª§ 4 ¦, f Õ ªA á Ô_ { 9 ~ ½ Ó& ñ d ` ¦ s 6 x K " f

Ð& ñ ` ¦ K Å Ò Table 1` ¦ % 3 H . x & Ï @Ü ¼ Ð Ò re ¦ 1 m`\ ¦ 8

£ ¤& ñ % i ` ¦ M : © Ô ¦S X & ñ ¸ H כ ` ¦ · ú Ã º e .

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Measurement Study of Metal Melting Liquid Scintillator Concentration – Sun Heang So et al. 1021

Table 1. Values of Gd concentration of sample by using different measuring devices and after calibration Gd concen- tration.

Measurement apparatus Gd concentration (

^mg_m`

) After calibration Gd concentration (

^mg_m`

)

Volume 0.119 ± 0.010 0.108 ± 0.005

Pipette 0.101 ± 0.005 0.101 ± 0.003

Mass 0.099 ± 0.008 0.094 ± 0.004

Table 2. Gd concentration of standard reference samples and its density.

Gd concentration (

^mg_m`

) Density (

_m`^g

)@23

^◦

C 10.00 ± 0.03 1.030 ± 0.002 20.00 ± 0.10 1.082 ± 0.002 30.00 ± 0.15 1.116 ± 0.002

Table 3. Values of Gd concentration by PGAA method.

Value Gd concentration (

^mg_m`

)

n=10 0.103 ± 0.007

n=11 0.108 ± 0.008

n=12 0.106 ± 0.008

3. PGAA U ê s0 n É ù p § Þ X ¢ ¤X N ËÊ Ý + s ÇÊ Ý

0 l

x ¸ ì r$ 3 É r ô Ç² D G " é ¶ § 4 ½ ¨" é ¶ _ ì r$ 3 6 x " é ¶ Ð

Ð (Hanaro)_ 7 £ ¤ µ 1 Ïy ~ ½ Ó oì r$ 3 (Prompt gamma neutron activation analysis)` ¦ s 6 x % i [6].

PGAA H Ù þ ì r$ 3 l Õ ü t _ @ /³ ð& h ~ ½ ÓZ O Ü ¼ Ð p t _ r

«

Ñ\ ¦ " é ¶ Ð_ × æ$ í Ð ¸ # r « Ñ ³ ð& h Ù þ ` ¦ ~ ½ Ó

$ í

Ù þ Ü ¼ Ð ¨ 8 r v H õ & ñ \ " f ~ ½ ÓØ ¦ ÷ & H \ -t ü < ~ ½ Ó

$ í

Ù þ s Ô æ õ ÷ & H õ & ñ \ " f ~ ½ ÓØ ¦ ÷ & H ~ ½ Ó (y )_

\

-t ü < ~ ½ Ó 0 p x` ¦ 8 £ ¤& ñ # r « Ñ_ & ñ $ í x 9 & ñ | ¾ Ó` ¦ ì r

$

3 H l Õ ü t s [7]. 8 £ ¤& ñ ` ¦ _ ø @ô Ç Ò re ¦ É r y l 0 l x ¸

É r 5 > h_ Ò re ¦` ¦ ï r q % i ¦ EDTA ~ ½ ÓZ O Ü ¼ Ð 8 £ ¤& ñ ô Ç Ò

&

ñ ÷ &% 3 . PGAA ~ ½ ÓZ O Ü ¼ Ð 0 l x ¸\ ¦ 8 £ ¤& ñ ô Ç õ \ ¦ Table 3 Ü ¼ Ð Í Ç x . LAB_ ò ø Í è(C)ü < Ã º è(H)_ q { 9

&

ñ t · ú §Ü ¼Ù ¼ Ð n = 10, 11, 12 y y _ â Ä º\ @ /K Gd _ 0 l x ¸ 8 £ ¤& ñ ) a õ ³ ðs . n = 11 â Ä º z ´ ]

4. 6 KT ' [Ñ ÷ R w + s ÇÊ Ý

RENO (Reactor Experiment for Neutrino Oscillation) z

´+ « > É r % ò F g _ " é ¶ Ð\ " f : r × æ$ í p \ ¦ s 6 x # 1

Fig. 1. (Color online) Calibration curves using reference samples. Input is certified Gd concentration and output is results of EDTA titration.

Ø ¦ l _ target\ H 0.1% [ t o ³ o u s 6 x K ) a + þ A· ú

~

´ $ H $ l ì ø Í Ó o^ $ 3 F g Ø ¦6 xÓ o` ¦ 6 x ¦ e .

"

f % i Z Ô æ õ \ " f µ 1 ÏÒ q t H × æ$ í í S \ r ç ß ` ¦ 8 £ ¤

&

ñ s ° ú כÜ ¼ ÐÂ Ò' [ t o ³ o u _ 0 l x ¸ Ð ¨ 8 í ß ½ + É Ã º e

. RENO õ \ Ø Ô í S \ r ç ß É r 27.7 ± 0.2 µs X

<, s כ ` ¦ [ t o ³ o u 0 l x ¸ Ð ¨ 8 í ß 0.108 ± 0.001%\ K

¼\ ¦ 6 x # [ t o ³ o u _ 0 l x ¸\ ¦ 8 £ ¤& ñ Ù þ ¡` ¦ M :ü < ¸

#

III. ~ ¿ W d l

×

æ$ í p Ø ¦ \ æ ¼s H LAB l ì ø Í Ó o^ $ 3 F g Ø ¦ 6 x Ó

o` ¦ ë ß H Ê ê, Ó o^ -Ó o^ Æ ÒØ ¦ ~ ½ ÓZ O ` ¦ : x K 6 xÓ o\ [ t o

³ o u` ¦ ∼0.1% 6 x K % i . $ í / B N& h z ´+ « >` ¦ 0 AK Ó o^

$ 3

F g Ø ¦6 xÓ o\ 6 x K ) a [ t o ³ o u _ 0 l x ¸\ ¦ & ñ S X y H

כ

É r × æ כ ¹ l M :ë H \ , # Q t ~ ½ ÓZ O Ü ¼ Ð [ t o ³ o u 0 l x

É

r x & Ï @\ s × ¼\ ¦ 6 x # GdLS Ò re ¦` ¦ G 2 [ % i ` ¦ M : s

t ë ß z ´] j RENOz ´+ « > X <s ' \ " f [ t o ³ o u \ _ K × æ

$ í

í S \ ÷ & H r ç ß Ü ¼ ÐÂ Ò' ¨ 8 í ß ô Ç 0 l x ¸ü < q § % i

`

· ú

Ã º e % 3 .

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1022 New Physics: Sae Mulli, Vol. 63, No. 9, September 2013

P

c p 8 ý ò k >

s

7 Hë H É r 2009¸ ¸ & ñ Â Ò (p A ½ Ó ¸õ < ÆÂ Ò)_ F " é ¶ Ü

¼ Ð ô Ç² D G ½ ¨ F é ß _ t " é ¶ (No. 2009-0083526, 2010- 0007850, NRF-2012M2B2A6030210) Ü ¼ Ð [ O w n ) a ô Ç² D G × æ

$ í

p ½ ¨ G ' p' ü < l í ½ ¨ \ O t " é ¶` ¦ ~ Ã Î Ã º' ) a

½ ¨e .

REFERENCES

[1] For RENO experiment, http://reno01.snu.ac.kr/

∼reno/wiki/index.php/Main Page (accessed May., 20, 2013).

[2] J. S. Park, S. B. Kim, J. S. Lee, B. C. Kim and S. H.

Kim et al., Sae Mulli 58, 62 (2009).

[3] J. K. Ahn, S. R. Baek, S. Choi, Y. Choi and I. S.

Chung et al., arXiv:1003.1391(2010)

[4] I. S. Yeo and K. K. Joo, New Phys.: Sae Mulli 61, 739 (2011).

[5] M. F. Richard and W. R. Ronald, Elementary Prin- ciples of Chemical Process (John Wiley & Sons, New York, 1978), p. 818.

[6] S. H. Byun, G. M. Sun and H. D. Choi, Nucl. Instrum.

Methods Phys. Res. A 487, 521 (2002).

[7] M. P. Failey, D. L. Anderson, W. H. Zoller, G. E.

Gordon and R. M. Lindstrom, Anal. Chem. 51, 2209 (1979).

[8] J. K. Ahn, S. Chebotaryov, J. H. Choi, S. Choi and

W. Choi et al., Phys. Rev. Lett. 108, 191802 (2012).

Measurement Study of Metal Melting Liquid Scintillator Concentration

Vol. 63, No. 9, September 2013, pp. 1019∼1022

New Physics: Sae Mulli, DOI: 10.3938/NPSM.63.1019

Measurement Study of Metal Melting Liquid Scintillator Concentration

Sun Heang So · Kyung Kwang Joo ∗

Institute for Universe & Elementary Particles, Department of Physics, Chonnam National University, Gwangju 500-757, Korea

(Received 9 July 2013 : revised 15 July 2013 : accepted 11 September 2013)

We confirmed that the measured Ga concentration well compares with the converted concentration value from experimental data.

PACS numbers: 13.15.+g

Keywords: Liquid Scintillator, Gd, Concentration, LAB, EDTA titration

8

c´  o  Ó ÞA 0 u  = k V È° Ë Ñ ß e È û s Ú Ó Þu  8 ý  Ò Þy ¢  ¤X N Ë R w   ì Å 



Ð` 9 á  ¥ · ® £# Ü  ¢ 9

∗



 z  @ / < Æ § Ó ü t o  < Æõ  Ä ºÅ Ò èw n    ½ ¨ è, F g Å Ò 500-757

(2013¸  7 Z 4 9{ 9  ~ Ã Î6 £ §, 2013¸  7 Z 4 15{ 9  Ã º& ñ  : r ~ Ã Î6 £ §, 2013¸  9 Z 4 11{ 9  > F  S X & ñ )

"

é

¶  \ " f ~ ½ ÓØ  ¦ ÷ &  H ×  æ$ í p  \  ¦   Ø  ¦ l  0 AK  ×  æ$ í p   ³ ð& h \  Ø  æ[  t ô  Ç Ê ê  ª   ü < ×  æ$ í  \  ¦ Ò q t

$ í

  H % i Z  ì ø Í6 £ x`  ¦ s 6 x ½ + É Ã º e   . ×  æ$ í    í S \  í ß ê ø Í é ß   & h `  ¦ ß ¼>  l  0 AK  Ó  o^ $ 3 F g  Ø  ¦6 xÓ  o

\

 [  t o ³ o u`  ¦ 6 x K ô  Ç . $ í / B N& h   z ´+ « >`  ¦ 0 AK " f  H [  t o ³ o u _  g Ë >  s   Â ÒÄ » & ³ © s  { 9 # Q t  · ú §



&

ñ % i  . s X O >   Ð& ñ  ) a [  t o ³ o u _  0 l x  ¸ ° ú כ`  ¦ z ´+ « > X <s ' \  _ K  ¨ 8  í ß   ) a 0 l x  ¸ ° ú כõ  q  §Ù þ ¡`  ¦ M :

¸ ú

 { 9 u    H  כ `  ¦ S X    ½ + É Ã º e  % 3  .

PACS numbers: 13.15.+g

Keywords: Ó  o^ $ 3 F g  Ø  ¦6 xÓ  o, [  t o ³ o u, 0 l x  ¸,   + þ A· ú ~ ´ $ H $ , EDTA & h & ñ

E-mail: [email protected]

1019

1020 New Physics: Sae Mulli, Vol. 63, No. 9, September 2013

I. ô v ÚP  Õ ÛT   Ó ÞA 0c Ü R  Ò Å] k ù°  oû m Ç Ö  Ö  M   m u

 = kV È° Ë Ñß e È û s Ú  Ó Þu  

×

 æ$ í p     Ø  ¦`  ¦ 0 AK  Ó  o^ $ 3 F g  Ø  ¦6 xÓ  o (Liquid Scintillator, LS)`  ¦  6 x  ¦ e    [1].  : r z ´+ « >\ " f  H   + þ

A· ú ~ ´ $ H $  (Linear Alkyl Benzene, C

H

-C

H

, n = 10 ∼ 13, LAB)`  ¦ l ì ø ÍÜ ¼ Ð Ó  o^ $ 3 F g  Ø  ¦ 6 xÓ  o`  ¦ Ò  re  ¦  Ð



6 x % i  .   + þ A· ú ~ ´ $ H $  É r ² D G ? /\  Ò q tí ß \ O ^  e  # Q ½ ¨

l  ~ 1  ¦, µ 1 Ï o& h  ¸ 130

C  Ð Z  }   î ß    . o < Æ& h ½ ¨



¸\   $ H $  ¦o \  ¦ t  ¦ e  l  M :ë  H \  + þ AF g$ í `  ¦ ` (# Q y n C

~

½ ÓØ  ¦ | ¾ Ó ¸ PC (Pseudocumene, C

H

) ü < q  §K  ¸ + 't  t

 · ú §  H . ± ú  É r f  ¨F g  ¸ ° ú כõ  |  y  û Z o \  ¦ t  ¦ e   Ü

¼ 9  2 ;¨ 8  â & h    © & h `  ¦ t  ¦ e    [2, 3]. y n C`  ¦ ? /l  0

Aô  Ç $ 3 F g ^  Ð 2,5-diphenyloxazole (PPO, C

H

NO)

\

 ¦  6 xÙ þ ¡ . ¢ ¸ô  Ç  © `  ¦    â l 0 AK  1,4,-bis(2- methylstyryl)-benzene (bis-MSB, C

H

N

O

)\  ¦ '  

Ù þ

¡ . z ´+ « >\    H 8 £ ¤& ñ Ò  re  ¦ \   H 3 g/` _  PPOü < 30 mg/`_  bis-MSB\  ¦ 0 l q # " f  6 x % i  .

×

 æ$ í p     Ø  ¦`  ¦ 0 AK  % i Z  (ν

+ ρ → e

+ n) Ô  æ õ

ì ø Í6 £ x`  ¦ s 6 x ½ + É  â Ä º s  ì ø Í6 £ x \ " f µ 1 ÏÒ q t   H ×  æ$ í  

\

 ¦ ¸ ú   í S \    H  כ s  ×  æ כ ¹  . ×  æ$ í    í S \  é ß   & h `  ¦ ß

¼>  l  0 AK  [  t o ³ o u`  ¦ 6 x K ô  Ç Ó  o^ $ 3 F g  Ø  ¦6 xÓ  o (Gadolinium-loaded Liquid Scintillator, GdLS)`  ¦  6 x ô

 Ç . [  t o ³ o u`  ¦   + þ A· ú ~ ´ $ H $ \  6 x K r v l  0 AK " f Ä » l

 o ç ß × ¼(Ligand)\  ¦   ½ + Ër &  Ä »l F K5 Å q (organometal- lic)`  ¦ ë ß × ¼  H ~ ½ ÓZ O `  ¦  6 xÙ þ ¡ . Ä »l  o ç ß × ¼  H F K5 Å q õ  6 x l

6 x B \  0 l q  H Ó ü t| 9  Ð  : r z ´+ « >\ " f  H Ø Ô4  ¤z ´í ß  (car- boxylic acid) ×  æ    TMHA (3,5,5-trimethylhexanoic acid)`  ¦  6 x % i  . TMHA\  ¦  6 x #  [  t o ³ o u`  ¦ 6 x K

ô  Ç Ó  o^ $ 3 F g  Ø  ¦6 xÓ  o_  î ß & ñ $ í , 6 x K  ¸, y n C ~ ½ ÓØ  ¦ | ¾ Ó 1 p x

×

Sun Heang So · Kyung Kwang Joo ^∗

c´ o Ó ÞA 0 u = k V È° Ë Ñ ß e È û s Ú Ó Þu 8 ý Ò Þy ¢ ¤X N Ë R w ì Å

Ð` 9 á ¥ · ® £# Ü ¢ 9

z @ / < Æ § Ó ü t o < Æõ Ä ºÅ Ò èw n ½ ¨ è, F g Å Ò 500-757

(2013¸ 7 Z 4 9{ 9 ~ Ã Î6 £ §, 2013¸ 7 Z 4 15{ 9 Ã º& ñ : r ~ Ã Î6 £ §, 2013¸ 9 Z 4 11{ 9 > F S X & ñ )

¶ \ " f ~ ½ ÓØ ¦ ÷ & H × æ$ í p \ ¦ Ø ¦ l 0 AK × æ$ í p ³ ð& h \ Ø æ[ t ô Ç Ê ê ª ü < × æ$ í \ ¦ Ò q t

H % i Z ì ø Í6 £ x` ¦ s 6 x ½ + É Ã º e . × æ$ í í S \ í ß ê ø Í é ß & h ` ¦ ß ¼> l 0 AK Ó o^ $ 3 F g Ø ¦6 xÓ o

[ t o ³ o u` ¦ 6 x K ô Ç . $ í / B N& h z ´+ « >` ¦ 0 AK " f H [ t o ³ o u _ g Ë > s Â ÒÄ » & ³ © s { 9 # Q t · ú §

ñ % i . s X O > Ð& ñ ) a [ t o ³ o u _ 0 l x ¸ ° ú כ` ¦ z ´+ « > X <s ' \ _ K ¨ 8 í ß ) a 0 l x ¸ ° ú כõ q §Ù þ ¡` ¦ M :

{ 9 u H כ ` ¦ S X ½ + É Ã º e % 3 .

Keywords: Ó o^ $ 3 F g Ø ¦6 xÓ o, [ t o ³ o u, 0 l x ¸, + þ A· ú ~ ´ $ H $ , EDTA & h & ñ

I. ô v ÚP Õ ÛT Ó ÞA 0c Ü R Ò Å] k ù° oû m Ç Ö Ö M m u

= kV È° Ë Ñß e È û s Ú Ó Þu

æ$ í p Ø ¦` ¦ 0 AK Ó o^ $ 3 F g Ø ¦6 xÓ o (Liquid Scintillator, LS)` ¦ 6 x ¦ e [1]. : r z ´+ « >\ " f H + þ

A· ú ~ ´ $ H $ (Linear Alkyl Benzene, C

, n = 10 ∼ 13, LAB)` ¦ l ì ø ÍÜ ¼ Ð Ó o^ $ 3 F g Ø ¦ 6 xÓ o` ¦ Ò re ¦ Ð

6 x % i . + þ A· ú ~ ´ $ H $ É r ² D G ? /\ Ò q tí ß \ O ^ e # Q ½ ¨

l ~ 1 ¦, µ 1 Ï o& h ¸ 130

C Ð Z } î ß . o < Æ& h ½ ¨

¸\ $ H $ ¦o \ ¦ t ¦ e l M :ë H \ + þ AF g$ í ` ¦ ` (# Q y n C

½ ÓØ ¦ | ¾ Ó ¸ PC (Pseudocumene, C

) ü < q §K ¸ + 't t

· ú § H . ± ú É r f ¨F g ¸ ° ú כõ | y û Z o \ ¦ t ¦ e Ü

¼ 9 2 ;¨ 8 â & h © & h ` ¦ t ¦ e [2, 3]. y n C` ¦ ? /l 0

Aô Ç $ 3 F g ^ Ð 2,5-diphenyloxazole (PPO, C

¦ 6 xÙ þ ¡ . ¢ ¸ô Ç © ` ¦ â l 0 AK 1,4,-bis(2- methylstyryl)-benzene (bis-MSB, C

)\ ¦ '

¡ . z ´+ « >\ H 8 £ ¤& ñ Ò re ¦ \ H 3 g/` _ PPOü < 30 mg/`_ bis-MSB\ ¦ 0 l q # " f 6 x % i .

æ$ í p Ø ¦` ¦ 0 AK % i Z (ν

+ n) Ô æ õ

ì ø Í6 £ x` ¦ s 6 x ½ + É â Ä º s ì ø Í6 £ x \ " f µ 1 ÏÒ q t H × æ$ í

¦ ¸ ú í S \ H כ s × æ כ ¹ . × æ$ í í S \ é ß & h ` ¦ ß

¼> l 0 AK [ t o ³ o u` ¦ 6 x K ô Ç Ó o^ $ 3 F g Ø ¦6 xÓ o (Gadolinium-loaded Liquid Scintillator, GdLS)` ¦ 6 x ô

Ç . [ t o ³ o u` ¦ + þ A· ú ~ ´ $ H $ \ 6 x K r v l 0 AK " f Ä » l

o ç ß × ¼(Ligand)\ ¦ ½ + Ër & Ä »l F K5 Å q (organometal- lic)` ¦ ë ß × ¼ H ~ ½ ÓZ O ` ¦ 6 xÙ þ ¡ . Ä »l o ç ß × ¼ H F K5 Å q õ 6 x l

6 x B \ 0 l q H Ó ü t| 9 Ð : r z ´+ « >\ " f H Ø Ô4 ¤z ´í ß (car- boxylic acid) × æ TMHA (3,5,5-trimethylhexanoic acid)` ¦ 6 x % i . TMHA\ ¦ 6 x # [ t o ³ o u` ¦ 6 x K

ô Ç Ó o^ $ 3 F g Ø ¦6 xÓ o_ î ß & ñ $ í , 6 x K ¸, y n C ~ ½ ÓØ ¦ | ¾ Ó 1 p x

æ$ í p z ´+ « >\ 9 כ ¹ô Ç $ í | 9 ` ¦ Ø æì r y ë ß 7 á ¤ r v l M : ë

H s . Ä »l F K5 Å q Gd-TMHA\ ¦ ] j ¸ H × æ oì ø Í6 £ xd

É

r 6 £ § õ ° ú .

(1) d É r Ø Ô4 ¤z ´í ß \ ¸m Ã º\ ¦ ' K " f × æ o r

v H ì ø Í6 £ xd s . Õ ª Ê ê (2) d \ " f H × æ or Ø Ô 4

¤z ´í ß õ GdCl

Ã º6 xÓ o` ¦ D ¥ ½ + Ë # Gd-TMHA Ä »l F K 5

q` ¦ ½ + Ë$ í ô Ç d s . : r z ´+ « >\ " f H [ t o ³ o u` ¦ ∼0.1%

x K % i [4].

II. Ò Þy ¢ ¤X N Ë U ê s0 n É õ m Í + s ÇÊ Ý

1. EDTA X ì ÄX N Ë ù p § Þ X ¢ Ò Þy ¢ ¤X N Ë

+ þ A· ú ~ ´ $ H $ l ì ø Í_ Ó o^ $ 3 F g Ø ¦ 6 xÓ o ? /_ [ t o

u 0 l x ¸\ ¦ · ú l 0 AK EDTA (Ethylene Diamine Tetra Acetic acid) & h & ñ (Titration) Z O ` ¦ 6 x % i . 100 m`

»o # î \ Ð ' a× æ Ò re ¦` ¦ # î _ × æ © \ " f { 9 r6 x x & Ï @

¦ s 6 x K è| ¾ Ó G 2 [K 8 £ ¤& ñ \ 6 x ô Ç . íí H Ã º (ultra pure water) \ buffer solution, t r x 9 GdLS Ò re ¦` ¦ 6

x K r Ê ê Â Ó Ï @Ü ¼ Ð EDTA\ ¦ ô Ç ~ ½ ÓÖ ¦m b # Qä ¼o " f

'

a ¹ 1 Ïô Ç . Ð Ò o t r _ Ò o¾ ú s ¸ê ø ÍÒ oÜ ¼ Ð H í

H ç ß t 6 x ô Ç EDTA_ ª ` ¦ · ú [ t o ³ o u _ 0 l x ¸\ ¦

í ß ½ + É Ã º e . Ò re ¦ É r 1 m`\ ¦ í í H Ã º\ 6 x K r ( H X <

Ò

re ¦ _ l ï r \ [ t o ³ o u 0 l x ¸ > í ß ° ú כs ß ¼> % ò ¾ Ó

¦ ~ Ã Îl M :ë H \ B jÛ ¼ e ¦ Û ¼ß ¼, x & Ï @, $ Ö ¦ y y _ ~ ½ ÓZ O

¦ s 6 x # Ò re ¦` ¦ G 2 [ô Ç Â Òx \ ¦ 8 £ ¤& ñ K " f õ ° ú כ` ¦ q

§K Ð ¤ . B jÛ ¼e ¦ Û ¼ß ¼_ ½ © É r 5.0 m` ± 0.1 s

¦ è HF K õ è HZ } s \ ¦ ´ ú 2 X" f Ò re ¦ _ & ñ | ¾ Ó` ¦ G 2 [ Ê ê & h & ñ

% i . x & Ï @ É r s ß ¼ Ð x & Ï @\ s × ¼ (100 ∼ 1000 µ`)\ ¦

6 x # 1000 µ` Ò re ¦` ¦ G 2 [ % i . $ Ö ¦ _ â Ä º $ Ò

re ¦` ¦ { É r B jÛ ¼e ¦ Û ¼ß ¼_ Á º> \ ¦ ± p Ê ê, G 2 [ô Ç Ò r e

¦` ¦ íí H Ã º\ 6 x K r v ¦ z É r B jÛ ¼e ¦ Û ¼ß ¼_ Á º> \ ¦ F

" f Õ ª Á º> s ü < x 9 ¸ (0.86 g/m`, 20

C)\ ¦ s 6 x K

f 0 l x ¸\ ¦ > í ß % i . s â Ä º B jÛ ¼e ¦ Û ¼ß ¼\ ³ ð \ z

É r Ò re ¦ _ Á º> \ ¦ ] jü @r v ¦ [ t o ³ o u _ 0 l x ¸\ ¦ > í

ß ½ + É Ã º e . Table 1 É r s [ j t ~ ½ ÓZ O Ü ¼ Ð EDTA & h

ñ ` ¦ ô Ç õ \ ¦ Ð# ï r .

2. »Ç U Ø Ó Þu ù p § T Ó Þ X ¢ R w

EDTA ~ ½ ÓZ O É r Ò re ¦ _ 0 l x ¸ o\ @ /ô Ç & ñ Ð\ ¦ Å Òt ë

ß Â Òx 8 £ ¤& ñ _ Ô ¦¢ - a $ í \ " f ¸ H ¸ Ð K ] X @ /& h

0 l x ¸\ ¦ & ñ S X y H כ É r # Q§ > . " f : r z ´+ « >\ " f

H 0 l x ¸\ ¦ & ñ S X y · ú ¦ e H ³ ðï r 6 xÓ o` ¦ ½ ¨{ 9 K " f & h & ñ