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SHE Research at RIKEN/GARIS
Kosuke Morita
Research Group for Superheavy Element, RIKEN Nishina CenterDepartment of Physics, Kyushu University,
RIKEN
Kyushu Univ.
2015/11/09 JCNP2015@OSAKA 1
RCNP
2015/11/09 2JCNP2015@OSAKA
3
120
119
118
117
116
115
114
113
112
Rg
Ds
Mt
Hs
Bh
Sg
Db
Rf
162 184
262
266
265264
262
261
261
260259
258
257 258 260259
260 261 262
263
262261
SHE
A
A
A
a-decay
Spontaneous fission
b+ or EC decay
one end of nuclear chart ’84 -’ 94
2015/11/09 JCNP2015@OSAKA
4
120
119
118
117
116
115
114
113
112
Rg
Ds
Mt
Hs
Bh
Sg
Db
Rf
162 184
262
266
265264
262
261
261
260259
258
257 258 260259
260 261 262
263
262261 263
265 266
267266
259
264
269 270 271
267266
262
272
268
269 270 271
277
278
273
274
261
270
265
263
264
267
267 268
268
271 272
271
275 276
275
279 280
279
278
281
284 285 286
282
282
283 284
283
287 288 289 290286
287 288
290 291 292 293
294
SHE
A
A
A
a-decay
Spontaneous fission
b+ or EC decay
263
278
274
270
294293
290289
286285
282281
one end of nuclear chart 2010
2015/11/09 JCNP2015@OSAKA
Main Limitations of Various Approaches to SHE
Reaction Mode Proj. (Aproj)
Limitation Heaviest Nuclide
comment
(Z) (N)
multiplen-capture
n SF* of Fm isotopes 100 157 maybe possible in nature (r-process)
hot fusion(HI,xn);x=3-6Ucn≥40 MeV
≤34&48
small survival prob.(Gn/Gf very small)
118 177 N-rich beam often improves.(cf. 48Ca;warm fusion)
cold fusion(HI,xn);x=1,2Ucn ≤20 MeV
50-70 small fusion prob.(dynamical hindrance of fusion?)
113 165
transferreaction
≤22 lack of target heavier than 254Es**
103 159
*SF: spontaneous fission. cf. T1/2 of 258Fm158 ≈ 400 ms.
**254Es(Z=99): T1/2 ≈ 276 day
52015/11/09 JCNP2015@OSAKA
2015/11/09 6
Linear Accelerator Facility
18GHz ECR Ion Source
RFQ-Linac
CSM Acc. Tanks RILAC Acc. Tanks
GARIS
Beam Energy Monitor
JCNP2015@OSAKA
2015/11/09 7
beamDifferential pumping section
D1
Bending angle 45 degreePole gap 150 mm
Radius of central ray 1200 mm
Maximum field 1.54 T
Q1, Q2
Pole length 500 mm
Bore radius 150 mm
Maximum field gradient 5.2 T/m
D2
Bending angle 10 degree
Pole gap 160 mm
Pole length 400 mm
Maximum Field 1.04 T
Magnification X -0.76Y -1.99
Dispersion 0.97 cm/%Total length 5760 mmAcceptance Dq ±68 mrad
Df ±57 mradDW 12.2 msr
Rotating Targetr 150 mmw 2000 rpm
RIKEN Gas-filled Recoil Separator GARIS
D1 Q1 Q2 D2
JCNP2015@OSAKA
11
1110
10
10
9
9
9
9
98
8
8
7
a1
a2
a3
a4
a5
11
11
1110
8
8
Ea (MeV)
5
0
5
0
5
0
5
0
5
0
Coun
ts/1
00ke
V
a1
a2
a3
a4
a5
Tdecay
Coun
ts/b
in 01000s10s0.1s1ms
5
05 1000s10s0.1s1ms
1000s10s0.1s1ms
1000s10s0.1s1ms
1000s10s0.1s1ms
5
0
5
0
5
0
10ms
a b
t=2.9ms t=120ms
t=77ms
t=1.0s
t=3.7s
t=220s
208Pb + 64Ni 272Ds*
271Ds
267Hs
263Sg
259Rf
255No
2015/11/09 JCNP2015@OSAKA 8
GSI/SHIPLBNL/BGSIMP/GFRS
2015/11/09 JCNP2015@OSAKA 9
2015/11/09 JCNP2015@OSAKA 10
NN2003 at Moscow 18Jun2003
Nuclei n T1/2
271110 11 1.63+0.44-0.29
ms improved
271m110 3 69+56-21
ms confirmed
267Hs 12 52+13- 8
ms improved
267mHs 1 0.80+3.8-0.38
s possible
Eopt(64Ni) = 314 MeV
Eopt(cm) = 240 MeV
Summary of 208Pb + 64Ni → 271110 + n reaction
K. Morita et al., EPJA 21, 257-263 (2004)2015/11/09 JCNP2015@OSAKA 11
0
5
0
5
0
5
0
5
0
5
Coun
ts /
bin 0
5
0
5
0
5
Coun
ts /
100
keV
E α / MeV
0
5
8 9 10 11 120
5
a1
a2
a3
a4
a5
a1
a2
a3
a4
a5
10000s100s1s10ms100ms
Tdecay
254Md ← 256Lr ← 260Db ← 264Bh ← 268Mt ← 272Rg
t=5.5ms
t=30ms
t=1.3s
t=8.2s
t=26s
2015/11/09 JCNP2015@OSAKA 12
8 9 10 11 12
1
2
7
9
12
14
3
4
5
6
8
10
11
13
272111268Mt
264Bh260Db256Lr
(e)F
(e)(e)
F
F
E (MeV)
48.5 s
21.0 s
0.33 s
1.91 s
2015/11/09 JCNP2015@OSAKA 13
NN2003 at Moscow 18Jun2003
RIKEN GSI
Nuclei n T1/2
Ea Efiss. n T1/2Ea
MeVMeV
272111 14 3.8+1.4- 0.8
ms 10.2~11.56 6 1.6+1.1-0.5
ms 10.8~11.05
268Mt 14 21+8- 5
ms 9.4~10.77 6 42+29-12
ms 10.1~10.3
264Bh 14 0.89+0.31- 0.19
s 8.86~9.83208206
6 1.0+0.7-0.3
s 9.1~9.6
260Db 12 5.7+2.3- 1.3
s 8.35~9.4 231 6 2.6+1.8-0.8
s 9.1~9.2
256Lr 8 18+10- 5
s 8.35~8.65 4 33+27-10
s 8.4~8.5
Eopt(64Ni) = 319 MeV
Eopt(cm) = 244 MeV
Summary of 209Bi + 64Ni → 272111 + n reaction
K. Morita et al., JPSJ 73, 1738-1744 (2004)2015/11/09 JCNP2015@OSAKA 14
ref.1 Hofmann S. et al., Z. Phys. A354, 229 (1996) 208Pb + 70Zn → 277Cn + n2 Hofmann S. and Münzenberg G., Rev. Mod. Phys. 72, 733 (2000) 208Pb + 70Zn → 277Cn + n3,4 J. Phys. Soc. Jpn., Vol. 76, No. 4, p.043201(2007) 208Pb + 70Zn → 277Cn + n
present 208Pb + 70Zn → 277Cn + n5 Lazarev Yu. A. et al., Phys. Rev. C54, 620 (1996) 244Pu + 34S → 273Ds + 5n6 Lazarev Yu. A. et al., Phys. Rev. C62, 064307(2000) 244Pu + 22Ne → 261Rf + 5n
GSI RIKEN FLNRref. 1 2 3 4 present 5 6
277Cn 11.45 11.17 11.09±.07 11.32±.04 11.07±.070.28 ms 1.41 ms 1.10 ms 1.22 ms 0.37 ms
273Ds 11.08 11.20 11.14±.04 11.15±.07 11.03±.07 11.350.11 ms 0.31 ms 0.52 ms 0.04 ms 0.373 ms 0.39 ms
269Hs 9.23 9.18 9.17 c 9.25±.07 9.14±.0419.7 s 22.0 s 14.2 s 0.27 s 36.01 s
265Sg 4.60 0.20 8.71±.04 8.70±.04 8.66±.07 8.637.40 s 18.8 s 23.0 s 79.9 s 13.84 s 158 s
261Rf 8.52 153 197 156 176 8.30±0.064.70 s 14.5 s 2.97 s 8.30 s 3.73 s 54+8
-4 s257No 8.34 8.22 8.24, 8.34
15.0 s 384 s 17 s
15
Cn
2015/11/09 JCNP2015@OSAKA
10ms 1ms 0.1s 10s 1000s
277Cn t = 0.86+0.69-0.26 ms
273Ds t = 0.27+0.22-0.08 ms
269Hs t = 18+15-6 s
265Sg t = 29+23-9 s
261Rf t =6.8+5.5-2.1 s
T_decay/s
RIKEN
GSI
N=165
N=163
N=161
N=159
N=157
RIKEN present
162015/11/09 JCNP2015@OSAKA
2015/11/09 JCNP2015@OSAKA 17
2015/11/09 18
278113
274111
270Mt
266Bh
CN
11.68 MeV344 μs30.49 mm
11.15 MeV9.260 ms30.40 mm
10.03 MeV 7.163 ms29.79 mm
9.08 MeV2.469 s30.91 mm
36.75 MeV30.33 mm
23 July 2004, 18:55
a
a
a
a
The first observation
262Db
204.05 MeV40.9 s30.25 mm
278113
274111
270Mt
266Bh
CN
11.52 MeV4.93 ms30.16 mm
11.31 MeV34.3 ms29.61 mm
2.32 MeV (escape)1.63 s29.45 mm
9.77 MeV1.31 s29.65 mm
36.47 MeV30.08 mm
2 April 2005, 2:18
209Bi + 70Zn → 278113 + n
a
a
a
a
262Db
192.32 MeV0.787 s30.47 mm
The second observation
s.f.s.f. JCNP2015@OSAKA
2015/11/09 JCNP2015@OSAKA 19
12 Aug. 2012The third observation
278113
274Rg
270Mt
266Bh
CN
11.82 MeV667 μs
10.65 MeV9.97 ms
10.26 MeV444 ms
9.39 MeV5.26 s
262Db
8.63 MeV126 s
258Lr
8.66 MeV3.78 s
α1
α2
α3
α4
α5
α6
254Md
266Bh0.6 s
α 9.29
SF (64%)
α (34%)262Db34 s
8.678.538.45
258Lr3.9 s
8.6548.6218.5958.565
Wilk et al., PRL 85, 2697 (2000).
Table of Isotopes, 8th ed. (1996).
254Md
α
• 6 (7) consecutive α decays
• reached to known 266Bh , 262Db , 258Lr
⇒ well confirm the 2004, 2005 events
Known nuclides
2015/11/09 JCNP2015@OSAKA 20
113
112 277Cn
111 272Rg
110 269Ds 270Ds 271Ds 273Ds
109 266Mt 268Mt
108 263Hs 265Hs 266Hs 267Hs 269Hs 270Hs 271Hs
107 261Bh 262Bh 264Bh 266Bh 267Bh
106 258Sg 259Sg 261Sg 263Sg
105 259Db 260Db
104 256Rf 260Rf 261Rf 262Rf
103 255Lr 257Lr 258Lr 259Lr 260Lr 261Lr 262Lr
102 256No 258No 260No 262No
101 253Md 254Md 259Md 260Md
100 252Fm 254Fm 255Fm 257Fm 258Fm 259Fm
99 251Es 253Es 256Es 257Es
98 250Cf 251Cf 252Cf 253Cf 254Cf 255Cf 256Cf
262Db
264Hs
265Sg 266Sg262Sg260Sg
263Db
263Rf
261Db257Db 258Db
257Rf 258Rf 259Rf
255Md 256Md 257Md258Md
259No
256Fm253Fm
255No
256Lr
257No254No
252Es 255Es254ES
278113
274Rg
270Mt
266Bh
262Db
a
a
a
a
SF
278113
274Rg
270Mt
266Bh
262Db
a
a
a
a
258Lr
a
254Md
a
254Fm
a
250Cf
1st event Jul. 23 20042nd event Apr. 2 20053rd event Aug. 12 2012
既知核種
209Bi + 70Zn n
2015/11/09 21
観測された崩壊のまとめ
JCNP2015@OSAKA
RIKEN K. Morita, K. Morimoto, D. Kaji, H. Haba, K. Okeki, Y. Kudo, Y. Wakabayashi, A. Yoneda, A. Yoshida, T. Onishi, Y. Kasamatsu,H. Hasebe, M. Huang, T. Ichikawa, R. Kanungo, K. Katori
Tokyo U. of Physics T. Sumita, K. TanakaSaitama U. T. Yamaguci, T. Akiyama, R. Sakai, S. YamakiNiigata U. H. Kudo, S. Goto, M. Murakami, H. murayama, Y. KariyaIMP Lanzhou H.-S. Xu , T. HuangU. Tokyo E. IdeguchiTohoku U. T. Suda, H. KikunagaJAEA N. Sato, H. Koura, S. MitsuokaYamagata U. F. Tokanai, T. Moriya, K. Mayama, M. Takeyama, S. Namai,
A. MashikoU. Tsukuba A. Ozawa, K. Sueki高能物理研究所 Y.-L. Zhao
Journal of the Physical Society of Japan, 73 (2004) 1593 – 1596.Journal of the Physical Society of Japan, 76 (2007) 045001.Journal of the Physical Society of Japan, 81 (2012) 103201.
Elm. 113
2015/11/09 JCNP2015@OSAKA 22
248Cm + 48Ca 296Lv* Experiment at RIKEN GARISDec. 1 - 12, 2013, Sep. 19 – Oct. 16, 2014
RIKEN D. Kaji, K. Morimoto, H. Haba, Y. Wakabayashi, M. Huang, J. Kanaya, A. Yoneda, A. Yoshida, K. Katori
Tokyo U. Sci. K. TanakaYamagata U. M. Takeyema, F. Tokanai, T. YoshidaSaitama U. S. Yamaki, T. YamaguchiNiigata U. M. MurakamiIMP Lanzhou Z. Gan, L. MaGSI H. Geissel, S. Hofmann, Y. Maurer, S. Heinz Kyushu U. K. Morita, K. Fujita, Y. Narikiyo, T. Tanaka, S. Yamamoto
2015/11/09 JCNP2015@OSAKA 23
Date Time/days
D(Ti)/mgcm-2
D(Cm)/mgcm-2
E(RILAC)MeV
Elab/MeV (b – c – e)
Ip/pmA
Dose/1018
Ex_296Lv/MeV
2/12 – 12/122013
10 0.90 0.265 262.0 251.0 - 250.0 - 249.0 800 4.3 41.5±1.0
19/9 – 16/102014
14.2 0.90 0.290 258.0 247.0 - 246.0 - 245.0 680 5.0 37.5±1.1
Sep. Oct.2015
0.9 0.220 266.7 254.3 44
RIKEN/GARIS
2015/11/09 JCNP2015@OSAKA 24
Ex_296Lv/MeV
Correlated events(decay chains)
41.5±1.0 3 (4n), 1 (3n), 1(3n?) tentative
37.5±1.1 1 (3n), 1 (3n?) tentative
44 0 preliminary
2015/11/09 JCNP2015@OSAKA 25
Summary
An isotope of the 113th element, 278113, was produced in the 209Bi + 70Zn 278113 + n reaction, and unambiguously identifiedvia genetic correlation, connected to the well known nuclides.
293Lv and 292Lv were produced in the 248Cm + 48Ca 296Lv* reaction
What’s Next (New Element Search) ?
294118
293117 294117
292Lv 293Lv 294Lv291Lv290Lv
295118
N = 174 175 176 177 178
2015/11/09 JCNP2015@OSAKA 26
Systematic study of the actinide based 50Ti -induced reactions.
248Cm + 50Ti 298118180*cf. 249Cf + 48Ca 297118179*
Future ?248Cm + 54Cr 302120182*
Study of new reaction mechanism (non-complete fusion) to produce SHE such as multi-nucleon transfer, or deep inelastic reaction of 248Cm + 238U?
Breakthrough is needed!
Spectroscopic studies of the isotopes of the heaviest element.Chemistry of superheavy Element.Mass measurement of SHE with MR-TOF (Wada-san’s group).
GARIS-II Experimental plans : New SHE search, mass measurement, SHE chemistry, SHE spectroscopy
2015/11/09 27
ERs
New SHE search
Reactive gasor He+KCl aerosol
ERs
Recoil transferchamber
SHE chemistry SHE spectroscopy
Mass measurement
TOF detector
Si-Gedetector BOX
Projectile
Beam envelope
Differentialpumping
Target
Beam dump
Gas inletFocal plane
0 1 [m]
D2
D1
Q2Q3
Q1
MRTOFMANON
JCNP2015@OSAKA
May 29 D. Kaji-san
May 29 M. Wada-san
2015/11/09 JCNP2015@OSAKA 28
Thank you very much for your kind attention.
248Cm+HI Pb/Bi+HI
GARIS
GARIS-II
0 1 2 3 4 5100
101
102
v/v0
Tran
smis
sion
[%]
High performance of GARIS-IIHigh Transmission under Low BG level
2015/11/09 29
E [MeV]
Coun
ts
5 6 7 8 9 100
20
40
0 5 10 1510 0
10 1
10 2
10 3
10 4
10 5
GARIS-II (dose=2.4x1014)
245 F
m
211m
Po211 P
o
211 A
t
210 A
t
210 P
o
211 B
i
211 B
i
245 E
s
241 C
f
GARIS (dose=6.4x1014)
Trans = 63%
245 F
m
Succeeded in the observation of Fm isotope produced by 208Pb(40Ar,3n)245Fm.Observed a-peak due to 245Fm in singles! BG level was about 5 times lower than GARIS. Trans was 1.5 times higher than GARIS.
23N
a26
Mg
27Al 48
Ca
JCNP2015@OSAKA
2015/11/09 JCNP2015@OSAKA 30
2015/11/09 JCNP2015@OSAKA 31
Aritomo & Hagino