Yu. Oganessian FLNR (JINR) PAC–meeting, June 22, 2009, Dubna D ubna JINR Experimental activities and main results of the researche at FLNR (JINR) Theme: Synthesis of new nuclei and study of nuclea properties and heavy-ion reaction mechani 03-05-1004-1994/2009
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Yu. Oganessian FLNR (JINR) PAC–meeting, June 22, 2009, Dubna Experimental activities and main results of the researches at FLNR (JINR) Theme: Synthesis.
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Yu. Oganessian
FLNR (JINR)
PAC–meeting, June 22, 2009, Dubna
Dubna
JINR
Experimental activities and main results of the researches at FLNR (JINR)
Theme: Synthesis of new nuclei and study of nuclear properties and heavy-ion reaction mechanism 03-05-1004-1994/2009
A&MA&M
ANLANL ORNLORNL IPNIPN INFN
Heavy ion accelerators
RIKENRIKEN
GANILGANILGSIGSI
MSUMSU
INFNINFN
Heavy Ion National Laboratories
Pioneers
LBLLBL
JINRJINR
BNLBNL CERNCERN
GSIGSI
Heavy Ion Colliders
Heavy ion physics: from the beginning to now…
RIB-FactoryRIB-FactoryRIBRIB
RIBRIB RIBRIB
RIBRIB
RIBRIB
Nuclei close to and beyond the border line
Light nuclei
neutrons
prot
ons
Heaviest nuclei
p/n - transfer & fragmentation p/n - transfer & fragmentation 2
50
50
50
82
28
28
20
208
82
/radioactive ion beams
beams of the neutron-rich projectiles: 3H(12.3y), 6He(0.8s) and 8He(0.12s)...
& target nuclei: 1,2H,3H(12.3y),3,4He
n
B
0
0
5
5
10
10
15
15
20
20 25 30 35
Z=2
Z=20
Z=2
Z=8Z=8
N=
2
N=
8
S ta b le Iso to p es
D ou b le M a g ic N uc le i
K no w n Iso to pe s
U nkn ow n Iso to p es
Pro
ton
Nu
mb
er
Neutron Num ber
N=
20
N=
28
36
N=
20
N=
28
28O
10He
n
B
0
0
5
5
10
10
15
15
20
20 25 30 35
Z=2
Z=20
Z=2
N=
28
N=
26
Z=8Z=8
N=
2
N=
8
N=
20
N=
16
S ta b le Iso to p es
D ou b le M a g ic N uc le i
K no w n Iso to pe s
U nkn ow n Iso to p es
Pro
ton
Nu
mb
er
Neutron Num ber
N=
20
N=
28
36
?
?
?
?
Shells in the light nucleiShells in the light nuclei
beams0.8s 0.1s
Radioactive ion beams
DIRECT
10m
0
R IB
400-cm cyclotron
400-cm cyclotron
low energy beam line
stable ion beams now 7Li
radioactive ion beams
DubnaRadioactive IonBeams
now 6He
Electronaccelerator
ISOL
now 8He
DIRECT
8He
d4H
6 8He + tHe and , d, p reactions
4n
n4
8He
t
t
7H
5H
5H
2n
2n
2nn
nn4
6He
tt
4He
4He
6He
d
t
4H
4H
t
tt
t
3H - target
t -
pro
jec
tile
s6
He
- p
roje
cti
les
8He
- p
roje
cti
les
2H - target H - target
d
p pt t
6He
8He
p
6He
p
tp
pt
t
t
4He
4He
2n
6He4He
4He
Neutron correlationsNeutron correlations
Strangely enough, but all the combinations:
3H, 6He, 8He (beams) + 1H, 2H, 3H (targets)
have been studied.
n
Be
B
C
B
N
F
Ne
10
12
6
6
4
4
2
20
8
8
O
He
Li
no shell effectwas observed
Unbound
strong shell effect in the “doubly-magic” nucleus
structure
discovery “di-neutron”
in halo-nucleus 6HeFLNR 2001
core
2n- halo
superheavyhydrogen
Be2p-emission
evidence of shell structure
5730y
n
Be
B
C
B
N
F
Ne
10
12
6
6
4
4
2
20
8
8
O
He
Li
discovery “di-neutron”
in halo-nucleus 6HeFLNR 2001
core
2n- halo
Be2p-emission
core
2p- halo?
Neβ+-2p emission
15O2p- halo?
0.11s
4He
PbSub-barrier fusion of halo nucleusSub-barrier fusion of halo nucleus
6He
6He
neutrontransfer
Pb
targets: Au, Pb
ECM - EB (MeV)
Cro
ss s
ectio
ns (
mb)
6He-neutrontransfer
4He-neutrontransfer6He-fusion
4He-fusion
Nuclear reactions induced by halo nucleiNuclear reactions induced by halo nuclei “of-line” gammameasurements
With Z >40% larger than that of Bi, the heaviest stable element, that is an impressive extension in nuclear survival.
Although the SHN are at the limits of Coulomb stability, shell stabilization lowers: the ground-state energy, creates a fission barrier, and thereby enables the SHN to exist.
The fundamentals of the modern theory concerning the mass limits of nuclear matter have obtained experimental verification
0
bb20 R
E
40
60
0
E (
MeV
)
5 10 15 20 25 30 35r
-40
-20
R
b
[V (r) - ] d r1 /2
E1 / Log ~T1/2 V (r )N
V C
V C+ V N 238 U
212 P o
V = V + VN C
Size of SH-nucleiSize of SH-nuclei
Geiger–Nutall relation Log Tα = C + D/√Qα
based on invariable density of nuclear matter and nuclear size:
R = r0·A1/3
perfectly works in theRegion: 212Po- 238U,where alpha-decay half-lives changed more than 1025 times!
7 8Alpha decay energy, Q (M eV)
Ha
lf-lif
e,
T (
s)
9
LogT =(a .Z+b).Q +c .Z+d-1 /2
1 0 11 1 2
106
106104
102
102Z = 100
1 0 -5
1 0 -3
1 0 -1
1 01
1 03
1 0 5
118
116
114
11 2
110
1 08
110
108106
100 -104
Cold fusion
Act.+48Ca
11 4
118
116
11 2
even
odd
available for chemical studies
Superheavy nuclei aren't exception to this rule
Chemical properties
7s
6s
5s
5d
4d4s3s2s
5fr max
rel /r
max
non-
rel
4f
Relativistic Contraction
non-
relativistic
7s
6s
5s
5d
4d4s3s2s
5f
4f
0,80
0,75
0,85
0,90
0,95
1,00
1,05
7s
6s
5s
6p5p4p
5d
4d
3p
4s3s2s
5f
0 20 40 60 80 100 120Z
1s 2p3d
4f
rm ax : principal maximum of the wave function of the outermost orbital
J.P. Desclaux, At. Data Nucl. Data Tables 12 , 311 (1973)J.P. Desclaux, At. Data . Data Tables 12 , 311 (1973)J.P. Desclaux, At. Data . Data Tables 12 , 311 (1973)