8πLP-CORSET TOF Spectrometer for FF 8πLP - INFN-LNL

8πLP-CORSET TOF
TOF Spectrometer
Spectrometer for
for FF
FF
8πLP-CORSET
A. Brondi, G. La Rana, R. Moro, M.Trotta, E. Vardaci,
INFN and Dipartimento di Scienze Fisiche dell’Università di Napoli
A. Chizhov, G.N. Kniajeva, E.M. Kozulin
Flerov Laboratory of Nuclear Reactions, JINR, 141980 Dubna
M. Cinausero, E. Fioretto, P.F. Mastinu, G. Prete, V. Rizzi
Laboratori Nazionali di Legnaro
N. Gelli, F. Lucarelli
INFN and Dipartimento di Fisica dell’Università di Firenze
FIESTA
FIssion of Excited Systems at Tandem-Alpi
•
Dinamica della Fissione in sistemi
di fissilita’ intermedia e in sistemi
pesanti;
•
Dipendenza della densita’ dei livelli
dall’isospin;
Fission time
time scale;
scale;
1.1. Fission
2. Strength
Strength and
and Nature
Nature of
of dissipation:
dissipation:
2.
one-body or
or two-body;
two-body;
one-body
3. Dependence
Dependence of
of the
the viscosity
viscosity on
on the
the
3.
temperature and
and on
on the
the shape.
shape.
temperature
Systems of Intermediate Fissility
(χ ≅ 0.5 - 0.6)
Î
Î ER
ER cross
cross section
section comparable
comparable or
or larger
larger than
than
the
the fission
fission cross
cross section:
section: more
more constraints
constraints
on
on the
the SM;
SM;
Î
Î larger
larger charged
charged particle
particle multiplicity
multiplicity (almost
(almost
an
an order
order of
of magnitude)
magnitude)
Î
Î role
role of
of pre-saddle
pre-saddle dynamics
dynamics enhanced
enhanced
compared
compared to
to saddle-to-scission-one
saddle-to-scission-one
Î
Î no
no much
much data
data on
on these
these systems
systems
Heavy Fragment Correlations and Identification
200 MeV
32S
+
100MoÆ132Ce
Light particles
Heavy Fragments
Δθ = 680-1040
Δθ = 870-1230
GANES <θFF> = 880
GANES <θFF> = 1000
Fission Events
Deep Inelastic collisions
Ring F-G
Ring G-G
Instrumental Upgrade
1. Time-Of-Flight Spectrometer for fission
fragments (CORSET, 2 arms + 2 arms)
2. New Annular PPAC for ER
The CORSET set-up
Fragment 1
Target 208Pb,
244Pu, M
target
Beam 48Ca 58Fe
Tof 1
position 1
60°
Mproj, Vproj
60°
Tof 2
position 2
Fragment 2
θ1,2
E1,2
M1,2
TKE
8πLP-CORSET
Stop
Start
L = 30/35 cm
1. 4 Start and Stop (4 arms, ring F and G)
2. NIM electronics for 2 arms
3. VME 32Ch TDC for 2 arms
The Start-Stop assembling
YLF
XLF
SpLF
YLG
XLG
Left
ring F
Left
ring G
beam
target
SpLG
StLF
StLG
StRG
Right
ring G
Right
ring F
StRF
SpRG
XRG
YRG
SpRF
XRF
YRF
8πLP-CORSET
QDC
HV
supply
TAC
CFD
CFD
Y2
X2
Sp2
St2
beam
St1
Sp1
TAC
TAC
Y2
X2
TOF2
ADC
ADC
ADC
CFD
splitter
Gate QDC
splitter
CFD
splitter
CFD
splitter
CFD
X1
Y1
CFD
CFD
HV
supply
Scheme of
coincidence
TAC
TAC
TAC
QDC
Start
TAC
Gate ADC
TOF1
X1
Y1
dT
ADC
ADC
ADC
ADC
Electronic modules
1. HV supply
- 4 channels
2. QDC
- 4 channels
3. CFD
- 8 channels
4. TAC
- 7 pieces
5. ADC
- 7 channels
CORSET Mass Resolution
Acn = 132 L = 35 Δt = 400ps
ΔΜ
FWHM = 300ps
Fine presentazione
180 MeV 32S + 109Ag: TKE vs. Mass
TKE vs. Mass
distributions for an
intermediate system
measured with a
CORSET setup