• 검색 결과가 없습니다.

Volume 60, Number 8, 2010¸ 8 Z 4, pp. 823∼826

N/A
N/A
Protected

Academic year: 2021

Share "Volume 60, Number 8, 2010¸ 8 Z 4, pp. 823∼826"

Copied!
4
0
0

로드 중.... (전체 텍스트 보기)

전체 글

(1)

Volume 60, Number 8, 2010¸   8 Z 4, pp. 823∼826

New Physics: Sae Mulli (The Korean Physical Society), DOI: 10.3938/NPSM.60.823

RENO ÷ m Ç] M ö; c" e à X Ø? _ õ u §z º S ö o Ú7 _T  Ó Å ù p § —  ޔ X ¢ •  ×} º] k ù ß e È û s ÚM 8 ý

° Ë

Ñ] K ¡X ì Ä — ¤V R Ë Ä Z ØV Ä Ž ì ŏ Œ

™ »( å ¾ 6 Ò · ® £# Ü  ¢ 9

Ä

ºÅ Ò ™ èw n   ƒ  ½ ¨™ è, „  z Œ ™@ /† < Ɠ § Ó ü t o † < Æõ , F g Å Ò 500-757

(2010¸   5 Z 4 31{ 9  ~ à Î6 £ §, 2010¸   6 Z 4 30{ 9  à º& ñ ‘ : r ~ à Î6 £ §, 2010¸   8 Z 4 9{ 9  > F  S X ‰& ñ )

RENO z  ´+ « >“ É r t F K  t  ¸ ú ˜ · ú ˜ 9t t  · ú §  H ×  æ$ í p   ™ D ¥ ½ + Ëy Œ • θ

13

_  [ jl \  ¦ 8 £ ¤& ñ l  0 Aô  Ç ² D G ? / " é ¶

„

  ×  æ$ í p   z  ´+ « >s  . RENO  Ž Ø  ¦ l \  ¦ ] j Œ • l  „  \  # Œ Q t  ½ ¨› ¸ % i † < Æ& h  : £ ¤$ í , F g † < Æ& h  $ í | 9  1 p x

`

 ¦ › ¸  l  0 AK  » ¡ ¤ ™ è+ þ A  Ž Ø  ¦ l \  ¦ ë ß –[ þ t% 3  . ‘ : r  7 Hë  H“ É r Geant4 \    H  ô  Ç GLG4Sim á Ԗ ÐÕ ªÏ þ ›`  ¦ s  6

 

x # Œ » ¡ ¤ ™ è+ þ A  Ž Ø  ¦ l _   7 H _ … \  ¦ – Ð r Ó ý t Y Us ‚  `  ¦ : Ÿ x K  \  -t  ì  r Ÿ í, F g  _  f  ¨ à º x 9 ~ ½ ÓØ  ¦, F f  ¨ à º x 9

F ~ ½ ÓØ  ¦, F g7 £ x; Ÿ ¤› ' a \  • ¸² ú ˜ô  Ç F g  à º 1 p x _  F g † < Æ& h  : £ ¤$ í `  ¦ ƒ  ½ ¨ % i “ ¦ RENO  Ž Ø  ¦ l ü < q “ § % i  .

Ù þ

˜d ” # Q: ×  æ$ í p  , ×  æ$ í p   ”  1 l x  ¨ 8 Š , RENO z  ´+ « >, F g   f  ¨ à º x 9 ~ ½ ÓØ  ¦

Feasibility Study on the Optical Properties of the RENO Detector and a Mock-up Using a Monte Carlo Simulation

Byoung Chan Kim · Kyung Kwang Joo

Institute for the Universe & Elementary Particles,

Department of Physics, Chonnam National University, Gwangju 500-757 (Received 31 May, 2010 : revised 30 June, 2010 : accepted 9 August, 2010)

The RENO experiment is to measure the unknown neutrino mixing angle θ

13

by using anti- neutrinos emitted from the Yonggwang nuclear power plant in Korea. A mock-up detector was made to test the mechanical structure and the optical properties of the detector before the construction of the RENO detector. In this research, we performed a Monte Carlo simulation of a mock-up based on the Geant4 simulation package. We compare the mock-up distribution of energy deposited, the quenched energy deposited, the absorption and the emission of photons, the number of photons arriving at photomultiplier tube with the results for the RENO detector.

PACS numbers: 25.20.-x, 29.25.Bx

Keywords: Neutrino, Neutrino oscillation, RENO experiment, Emission and re-emission

I. W _ ˰ Ë Ñ Ì ¦ R z º ú n ÞV R ËQ   ÷ m Ç] M ö

RENO (Reactor Experiment for Neutrino Oscillation) z 

´+ « >“ É r % ò F g " é ¶  § 4  µ 1 τ  ™ è\ " f 1.3 kmü < 290 m b  # Q

”

  ¿ º / B M \  1 l x{ 9 ô  Ç  Ž Ø  ¦ l \  ¦ [ O u ô  Ç Ê ê ¿ º  Ž Ø  ¦ l \ " f

E-mail: [email protected]

8

£ ¤& ñ  ) a ×  æ$ í p  _  € ª œ`  ¦ q “ §† < ÊÜ ¼– Ð+ ‹ ×  æ$ í p  _    ¨ 8 Š

&

ñ • ¸\  ¦ 8 £ ¤& ñ   H z  ´+ « >s  . ×  æ$ í p    H „    ×  æ$ í p  , Á

»“ : r ×  æ$ í p  , Ä º ×  æ$ í p  – Ð ì  r À Ó÷ &  H X <, 1990¸   Ê ê ì

ø Í { 9 ‘ : r \ " f ×  æ$ í p   | 9 | ¾ Ó`  ¦ ° ú   H    H  כ `  ¦ µ 1 Ï| Ù þ ¡



 [1]. Õ ªo “ ¦ [ j ×  æ$ í p    s \   H { 9  _  1 l x& h  $ í

| 9

\  _ K    É r 7 á x À Ó_  ×  æ$ í p  – Ð  7   H ”  1 l x  ¨ 8 Š s  { 9

# Q   H X <   ¨ 8 Š _  [ jl   H θ

12

, θ

23

, θ

13

– Ð ³ ð‰ & ³ ) a  . s 

-823-

(2)

-824- ô  Dz D GÓ ü t o † < Æ rt  “D hÓ ü t o ”, Volume 60, Number 8, 2010¸   8 Z 4

Fig. 1. A schematic view of Mock-up detector.

×

 æ θ

13

  H  f ”   © œô  ǰ ú כë ß – · ú ˜ 94 R e ” “ ¦ & ñ S X ‰ ô  Ç ”  1 l x  © œÃ º

° ú

כ“ É r 8 £ ¤& ñ t  3 l wÙ þ ¡  [2].   " f s  כ `  ¦ 8 £ ¤& ñ l  0 A K

 á Ô| ½ ÓÛ ¼_  Double Chooz, ×  æ² D G _  Daya Bay, ô  Dz D G _  RENO z  ´+ « >s  | [ O  ×  æ s   [3–5].

% ò

F g " é ¶  § 4  µ 1 τ  ™ è  H 6 > h_  " é ¶  – Ж Ð ½ ¨$ í ÷ &# Q e ” “ ¦ Ø

 ¦§ 4  ½ ©— ¸  H \ P  Ò q tí ß – l ï  r Ü ¼– Ð 17.3 GW“  X < [ j> \ " f

¿

º   P :– Ð Ø  ¦§ 4 s  Z  } “ ¦, Ø  ¦§ 4 \  q Y V # Œ ´ ú §“ É r ×  æ$ í p  

\

 ¦ ~ ½ ÓØ  ¦ ô  Ç . ‘ : r ƒ  ½ ¨  H RENO z  ´+ « >_   7 H _ … \  ¦ – Ð ì  r$ 3 

\

  6   x ÷ &  H ™ èá Ôà ÔJ ?# Q J v t \  ¦ s 6   x # Œ » ¡ ¤ ™ è+ þ A  Ž  Ø

 ¦ l _  F g † < Æ& h  : £ ¤$ í `  ¦ ì  r$ 3  % i “ ¦ RENO  Ž Ø  ¦ l ü < q 

“

§ % i  .

II. •  ×} º] k ù ß e È û s ÚM (Mock-up)

»

¡

¤ ™ è+ þ A  Ž Ø  ¦ l   H RENO  Ž Ø  ¦ l \  ¦ ] j Œ • [ O u  l  „  

\

 Ó  o^ ‰$ 3 F g Ž Ø  ¦6   xÓ  o ] j› ¸, „   — ¸Ñ ý t 1 l x  Œ •, X <s '  S \ ‰1 p q x 9

% ƒo  r Û ¼% 7 ›  Œ •1 l x Ä »Á º 1 p x`  ¦ Ÿ í† < Êô  Ç RENO  Ž Ø  ¦ l _  F

‰ & ³ x 9 # Œ Q t  $ í 0 p x`  ¦ _ …Û ¼à Ô l  0 AK  ë ß –[ þ t% 3  . ^ ‰

&

h q   H RENO  Ž Ø  ¦ l _  1/10s “ ¦ RENO  Ž Ø  ¦ l _  n  

“

 õ  1 l x{ 9  >  ] j Œ • % i  . RENO  Ž Ø  ¦ l   H " é ¶: Ÿ x — ¸€ ª œ Ü

¼– Ð 4% ò % i Ü ¼– Ð s À Ò# Q4 R e ”   H X < î ß –A á ¤ Ü ¼– РÒ'   ¿ , y Œ ™



H 5 g, ! Q( , q ž Ж Ð ½ ¨$ í ÷ &# Q e ”  .

»

¡

¤ ™ è+ þ A  Ž Ø  ¦ l   H Fig. 1 \ " f ˜ Ð1 p w s  RENO  Ž Ø  ¦ l \ 

"

f q ž Ð Â Òì  r s  ] jü @÷ &# Q e ”  . » ¡ ¤ ™ è+ þ A  Ž Ø  ¦ l _   [ jô  Ç ß

¼l   H Table 1 \  כ ¹€  •÷ &# Q e ”  . » ¡ ¤ ™ è+ þ A  Ž Ø  ¦ l _   ¿ õ

 y Œ ™ H % ƒ  H Ó  o^ ‰$ 3 F g Ž Ø  ¦6   xÓ  oÜ ¼– Ð G 0 >4 R e ” # Q" f Ó  o

^

‰$ 3 F g Ž Ø  ¦ Ó ü t| 9 `  ¦ 2 [/ å L   H # Œ Q › ' aº   r Û ¼% 7 ›[ þ t`  ¦ _ …

Fig. 2. Distribution of energy deposit by using Co

60

, Cs

137

, Ge

68

, Na

22

sources.

Û

¼à Ô ½ + É Ã º e ”  . ¢ ¸ô  Ç ! Q(  î ß –\   H 10“  u  Hamamatsu R7801 _  F g7 £ x; Ÿ ¤› ' a s  [ O u ÷ &# Q e ”   [6]. # Œ Q t  ~ ½ Ó 

‚

  ™ èÛ ¼\  @ /ô  Ç  7 H _ … \  ¦ – Ð r Ó ý t Y Us ‚  `  ¦ : Ÿ x K  » ¡ ¤ ™ è+ þ A

 Ž

Ø  ¦ l _  ì ø Í6 £ x \  @ /K  · ú ˜  ^  ¦ à º e ”  .

III. RENO S ö o Ú7 _T  Ó Å } º³ ޲ Ž ú# a

RENO r Ó ý t Y Us ‚  `  ¦ l  0 AK " f  H o ³ n q Û ¼  © œ

\

" f Geant4\  l ì ø Í`  ¦ é  H GLG4sim`  ¦  6   xÙ þ ¡ .

GLG4sim  H “GenericLAND Geant4 simulation” s “ ¦ LAND  H “Liquid-scintillator Anti-Neutrino Detector(as in KamLAND)”\  ¦ _ p ô  Ç .   " f GLG4Sim“ É r Kam- LAND z  ´+ « >\ " f Geant4\  l ì ø Í`  ¦ é  H % i Z …  Ô  æ õ _  _  ô

 Ç ×  æ$ í p   z  ´+ « >`  ¦ 0 AK  ë ß –Ž  H  7 H _ … \  ¦ – Ð r Ó ý t Y Us ‚   J

v t s “ ¦,   É r z  ´+ « >\ " f• ¸ ™ èÛ ¼  ï× ¼\  ¦  Ä »\  v >    6

 

x ½ + É Ã º e ” • ¸2 Ÿ ¤ ) ‡| Ã Ì “ ¦ e ”   [7]. RENO\ " f  H z  ´+ « >\ 

´ ú

>  # Œ Q Ó ü t o & h    à º[ þ t`  ¦  r  à º& ñ “ ¦ ™ èÛ ¼  ï× ¼\  ¦



  â K " f  6   x “ ¦ e ”  .

IV. Ä Z ØV Ä õ m Í + s ÇÊ Ý

RENO  Ž Ø  ¦ l  x 9 » ¡ ¤ ™ è+ þ A  Ž Ø  ¦ l _  r Ó ý t Y Us ‚  `  ¦ 0 A K

 GLG4Sim_  2.0.4-mocksim ¨ 8 Š â \ " f á Ԗ ÐÕ ªÏ þ ›`  ¦ [  t



9  A ü < ° ú  “ É r   õ \  ¦ % 3 % 3  . ì  r$ 3 `  ¦ 0 AK  ~ ½ Ó ‚   1 l x 0

A" é ¶ ™ è– Ð  H Co

60

, Cs

137

, Na

22

, Ge

68

™ èÛ ¼\  ¦  6   x % i  .

Fig. 2  H ~ ½ Ó ‚   ™ èÛ ¼\  ¦ » ¡ ¤ ™ è+ þ A  Ž Ø  ¦ l _  ×  æ € © œ\  Z  ~ € Œ ¤`  ¦ M

: F g   \  -t \  ¦ { 9 >  ÷ &  H X < Ó  o^ ‰$ 3 F g Ž Ø  ¦6   xÓ  o\ 

»

¡ ¤& h  ) a \  -t \  ¦ Õ ª 2 ;  כ Ü ¼– Ð Co

60

“ É r 2.6 MeV, Cs

137

“ É r

(3)

RENO z  ´+ « >\ " f  7 H _ … \  ¦ – Ð r Ó ý t Y Us ‚  `  ¦ : Ÿ x ô  Ç » ¡ ¤ ™ è+ þ A  Ž Ø  ¦ l _  F g † < Æ& h  : £ ¤$ í · · · – ^ ” # î ð ø Í 1 p x -825-

Fig. 3. Distribution of energy deposit quenched by using Co

60

, Cs

137

, Ge

68

, Na

22

sources.

Fig. 4. Comparison of energy deposit quenched between RENO and Mock-up.

0.66 MeV, Ge

68

“ É r ∼ 1 MeV s “ ¦, Na

22

  H ¿ º > h_  y Œ ™ 

 ~ ½ ÓØ  ¦ ÷ &l  M :ë  H \  ¿ º > h_  ’    ñ Ò q t|   . Õ ªA " f 1.25 MeV& ñ • ¸ü < 2.3 MeV\  ’    ñ e ” 6 £ §`  ¦ · ú ˜ à º e ”  .

Figure 3“ É r » ¡ ¤& h  ) a \  -t  › ¸F K   t   H \  -t  ì  r

Ÿ

í\  ¦   ? /“ ¦ e ”  . " é ¶ A  \  -t ˜ Ð  y Œ ™™ è   H X < s Ä »



 H # Œ Q t  e ” t ë ß – F g   ”  ' Ÿ † < Ê\     Å Ò0 A_  { 9 



[ þ t õ  Ø  æ[  t K  \  -t \  ¦ { 9 # Q ! Qw n = M : Õ ª \  -t \  ¦ — ¸

¿

º y n CÜ ¼– Ð  r  F ~ ½ ÓØ  ¦ t  · ú §l  M :ë  H s  .

ô

 Ǽ #  „   (e-)\  ¦  Ž Ø  ¦ l _  ×  æ € © œ\  Z  ~ “ ¦ 0.612 MeV \ 



-t \  ¦ Å Ò# Q  Ž Ø  ¦ l  ? /\ " f # Qb  G>  F g„   [ þ t`  ¦ µ 1 ÏÒ q tr  v

“ ¦ F g  _  f  ¨ à º x 9 ~ ½ ÓØ  ¦ 1 p x`  ¦   H t  · ú ˜ ˜ Ðl  0 A K

 1000> h_  s  $ ™à Ô\  ¦ Ò q t$ í % i  . Fig. 4  H RENO ü <

Mock-up \ " f   t   H \  -t _  ì  r Ÿ í\  ¦    · p  כ s  .

Fig. 5. Emission spectrum as a function of wavelength between RENO and Mock-up.

Fig. 6. Re-emission spectrum as a function of wavelength between RENO and Mock-up.

 Ž

Ø  ¦ l  ×  æ € © œ\ " f Ò q t$ í  ) a „   _  { 9 # Q! Q 2 ; \  -t \  _  K

 Ò q t|   F g   Ó  o^ ‰$ 3 F g Ž Ø  ¦6   xÓ  o`  ¦ t  €  " f f  ¨ à ºü < ~ ½ Ó Ø

 ¦`  ¦ > 5 Å q   H X < ¨ î ç  H ° ú כs  RENO  Ž Ø  ¦ l ü < » ¡ ¤ ™ è+ þ A  Ž Ø  ¦ l

\ " f €  • 0.02 s   “ ¦ e ”  . Fig. 5  H RENO  Ž Ø  ¦ l

ü < » ¡ ¤ ™ è+ þ A  Ž Ø  ¦ l \ " f ~ ½ ÓØ  ¦ ) a F g  [ þ t _   © œ ì  r Ÿ í“   X

< { 9  à ºü < ¨ î ç  H ° ú כ, z  ´´ ò° ú כs   _  1 l x{ 9   . ¢ ¸ô  Ç Fig.

6“ É r F g  \  ¦ f  ¨ à ºô  Ç Ê ê F ~ ½ ÓØ  ¦ ½ + É M :_  ì  r Ÿ í\  ¦   ? /  H X

< » ¡ ¤ ™ è+ þ A  Ž Ø  ¦ l ü < RENO_   Ž Ø  ¦ l   s \   H s   H

˜

Ðs t  · ú §€ Œ ¤ . ì  r$ 3    õ \  ¦ Table 2 \  כ ¹€  • % i  . þ j7 á x

&

h Ü ¼– Ð F g7 £ x; Ÿ ¤› ' a \  • ¸² ú ˜K  ë ß –[ þ t # Q”   F g„    à º  H €  • 2C 

(4)

-826- ô  Dz D GÓ ü t o † < Æ rt  “D hÓ ü t o ”, Volume 60, Number 8, 2010¸   8 Z 4

Table 1. Summary of the Mock-up detector dimensions.

Detector component Material Type Thickness (mm) Diameter (cm) Height (cm) Volume (m

3

)

Target Acrylic Gd(0.1 %) + LAB 10 60 60 0.17

Gamma catcher Acrylic LAB 10 140 140 1.99

Buffer Stainless steel Mineral oil 4 220 220 621

Table 2. Summary table of the number of optical photon arrived at PMT between RENO & Mock-up.

RENO RENO Mock-up

software detector detector

# of event 1000 1000

Electron energy generated 0.612 MeV 0.612 MeV Quenched energy (MeV) 0.5807 0.5707

# of emission photons 1350557 1330890

# of emission absorbed photons 803566 680118

# of reemission photons 566113 442409

# of reemission absorbed photons 279548 186048

# of photons arrived at PMT ∼ 833556 ∼ 907132

# of estimated number of photons ∼ 81272 ∼ 39460

_

 s  z Œ ™`  ¦ · ú ˜ à º e ” % 3  . Õ ª s Ä »  H RENO \ " f   6

 

x   H F g7 £ x; Ÿ ¤› ' a _  € ª œ  ´ òÖ  ¦(quantum efficiency)  H 25

% – Ð 1 l x{ 9  t ë ß – RENO  Ž Ø  ¦ l _   â Ä º F g7 £ x; Ÿ ¤› ' a _  8 ú x é

ß –€  & h “ É r 13 %“  X < » ¡ ¤ ™ è+ þ A  Ž Ø  ¦ l   H 6 % s l  M :ë  H s  .

V. ‚ º 8 ý

RENO z  ´+ « >“ É r ×  æ$ í p   ”  1 l x   ¨ 8 Š  © œÃ º θ

13

\  ¦ & ñ x 9  

>

 8 £ ¤& ñ l  0 Aô  Ç ² D G ? / þ jœ í_  z  ´+ « >s  . RENO z  ´+ « >`  ¦

l  · ú ¡" f » ¡ ¤ ™ è+ þ A  Ž Ø  ¦ l \  ¦ ] j Œ • % i “ ¦  Ž Ø  ¦ l _  $ í 0 p x x 9

l 0 p x`  ¦  7 H _ … \  ¦ – Ð r Ó ý t Y Us ‚   ~ ½ ÓZ O `  ¦ s 6   x % i  .

Co

60

, Cs

137

, Na

22

, Ge

68

_  ™ èÛ ¼\  ¦ s 6   x K " f » ¡ ¤ ™ è+ þ A  Ž Ø  ¦ l

_  » ¡ ¤' ‘  ) a \  -t  ì  r Ÿ í\  ¦ ¶ ú ˜( R˜ Ѐ Œ ¤“ ¦ 0.612 MeV \  - t

\  ¦ ”   „   \  ¦  Ž Ø  ¦ l _  ×  æ € © œ\  µ 1 ÏÒ q tK  » ¡ ¤ ™ è+ þ A  Ž Ø  ¦ l

ü < RENO  Ž Ø  ¦ l \ " f Ò q t$ í  ) a F g  _  f  ¨ à º x 9 ~ ½ ÓØ  ¦  ) a

>

hà º\  ¦ q “ § % i   H X < \ V © œõ   _  1 l x{ 9 ô  Ç ° ú כ`  ¦ % 3 % 3  .

P

c p 8 ý ò k >

s

  7 Hë  H“ É r 2010¸   „  z Œ ™@ /† < Ɠ § † < ÆÕ ü t ƒ  ½ ¨q  t " é ¶ \  _ 

# Œ ƒ  ½ ¨÷ &% 3 6 £ §.

Y

c p w Š à U Ø ”  ô

[1] Y. Ashie et al., Measurement of Atmospheric Neu- trino Oscillation Parameters Super-Kamiokande1 (Super-Kamiokande Collaboration), Phys. Rev. D 71, 112005 (2005).

[2] H. Geogy and S. L. Glashow, Phys. Rev. Lett. 32, 438 (1974).

[3] http://doublechooz.in2p3.fr [4] http://dayawane.ihep.ac.cn [5] http://reno01.snu.ac.kr/∼reno

[6] http://sales.hamamatsu.com/en/products/electron-

tube-division/detectors/photomultiplier-tubes.php

[7] http://neutrino.phys.ksu.edu/∼GLG4sim/

수치

Fig. 2. Distribution of energy deposit by using Co 60 , Cs 137 , Ge 68 , Na 22 sources
Fig. 5. Emission spectrum as a function of wavelength between RENO and Mock-up.
Table 2. Summary table of the number of optical photon arrived at PMT between RENO &amp; Mock-up.

참조

관련 문서

If both these adjustments are considered, the resulting approach is called a bootstrap-BC a -method (bias- corrected-accelerated). A description of this approach

③ A student who attended Korean course at KNU Korean Language Program and holds TOPIK Level 3 or a student who completed Korean course Level 4 at the KNU Korean Language

· 50% exemption from tuition fee Ⅱ for the student with a TOPIK score of level 3 or higher or completion of level 4 or higher class of the Korean language program at the

Since every classical or virtual knot is equivalent to the unknot via a sequence of the extended Reidmeister moves together with the forbidden moves, illustrated in Section 2,

웹 표준을 지원하는 플랫폼에서 큰 수정없이 실행 가능함 패키징을 통해 다양한 기기를 위한 앱을 작성할 수 있음 네이티브 앱과

_____ culture appears to be attractive (도시의) to the

At high temperature. During gas molecular collisions, kinetic energy is temporarily converted into potential energy. As the average intermolecular distance increases, the

If the volume of the system is increased at constant temperature, there should be no change in internal energy: since temperature remains constant, the kinetic