alessandro feliciello - istituto nazionale di fisica...
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A. F
elic
iello
/ IE
EE N
ucle
ar S
cien
ce S
ympo
sium
and
Med
ical
Imag
ing
Con
fere
nce,
Hon
olul
u, H
awai
i, U
SA, O
ctob
er 2
7-N
ovem
ber 3
, 200
7.
Alessandro FelicielloI.N.F.N. -
Sezione di Torino
The new FINUDA challenge: γ-ray spectroscopy of hypernuclei
at DAΦNE
The new FINUDA challenge: γ-ray spectroscopy of hypernuclei
at DAΦNE
γn
nnn
np
pp
p ppΛ
2A.
Fel
icie
llo /
IEEE
Nuc
lear
Sci
ence
Sym
posi
um a
nd M
edic
al Im
agin
g C
onfe
renc
e, H
onol
ulu,
Haw
aii,
USA
, Oct
ober
27-
Nov
embe
r 3, 2
007. Outline Outline
Discovery potential of the strangeness nuclear physics
Need of sub-MeV resolutionapparatuses
γ-ray spectroscopy
Ideas for FINUDA spectrometer upgrade at DAΦNE/DAΦNE2
3A.
Fel
icie
llo /
IEEE
Nuc
lear
Sci
ence
Sym
posi
um a
nd M
edic
al Im
agin
g C
onfe
renc
e, H
onol
ulu,
Haw
aii,
USA
, Oct
ober
27-
Nov
embe
r 3, 2
007.
(low-energy) YN interaction
detailed knowledge of the hypernuclear fine structure
→ evaluation of the spin dependent terms of the ΛN interaction
measurement of angular distribution of γ–rays
→ determination of spin and parity of each observed level
Impurity nuclear physicsmeasurement of transition probability B(E2)
→ information on the size and deformation of hypernuclei
→ measurement of nucleus core shrinking → glue-like role of Λ
Properties of hyperons in nuclear matter (medium effect)measurement of transition probability B(M1)→ g-factor value for Λ in nuclear matter
Open questionsOpen questions
4A.
Fel
icie
llo /
IEEE
Nuc
lear
Sci
ence
Sym
posi
um a
nd M
edic
al Im
agin
g C
onfe
renc
e, H
onol
ulu,
Haw
aii,
USA
, Oct
ober
27-
Nov
embe
r 3, 2
007.
energy 510 MeV
luminosity 5 1032
cm-2
s-1
σx (rms) 2.11 mm
σy (rms) 0.021 mm
σz (rms) 35 mm
bunch length 30 mm
crossing angle 12.5 mrad
frequency (max) 368.25 MHz
bunch/ring up to 120
part./bunch 8.9 1010
current/ring 5.2 A (max)
FINUDA @ DAΦNE FINUDA @ DAΦNE
−Λ
−
+−+−
+→+
→→+
π
φ
ZZΚΚΚee
AAstop
→Λ ZA
nnZnpZ
Z
A
A
A
++
++−
++
−
−
−
)2(
)2( )1()1( π
5A.
Fel
icie
llo /
IEEE
Nuc
lear
Sci
ence
Sym
posi
um a
nd M
edic
al Im
agin
g C
onfe
renc
e, H
onol
ulu,
Haw
aii,
USA
, Oct
ober
27-
Nov
embe
r 3, 2
007. The status of the artThe status of the art
ΔE ~
1.6
5 MeV
FW
HM
ΔE ~
1.6
5 MeV
FW
HM
ΔE ~
1.9
5 MeV
FWHM
ΔE ~
1.9
5 MeV
FWHM
ΔE ~ 1.29 MeV
FWHMΔE ~ 1.29 MeV
FWHM
−BΛ (MeV)
Cap
ture
rat
e/0.
25 M
eV x
10−
3
0
0.1
0.2
0.3
0.4
0.5
0.6
−25 −20 −15 −10 −5 10 150 5
#6
#4#3
#2
#1#5
#7
b)M. Agnello et al., Phys. Lett. B 622 (2005) 35 M. Agnello et al., Phys. Lett. B 622 (2005) 35
( ) CK,π 12Λ
++
ΔE ~
1.4
5 MeV
FWHM
ΔE ~
1.4
5 MeV
FWHM
f-orb
it sp
littin
g
into t
wo pea
ks ob
serve
d?
f-orb
it sp
littin
g
into t
wo pea
ks ob
serve
d?
6A.
Fel
icie
llo /
IEEE
Nuc
lear
Sci
ence
Sym
posi
um a
nd M
edic
al Im
agin
g C
onfe
renc
e, H
onol
ulu,
Haw
aii,
USA
, Oct
ober
27-
Nov
embe
r 3, 2
007. The status of the artThe status of the art
7Li(K-
,π-)12C7Li(K-
,π-)12C−stopK Li7
Λ
KEK E419
KEK E419
ΔE ~ 1.1 MeV FWHMΔE ~ 1.1 MeV FWHM
ΔE ~ 2 keV
FWHMΔE ~ 2 keV
FWHM
3
order of magnitude!!!3
order of magnitude!!!
7A.
Fel
icie
llo /
IEEE
Nuc
lear
Sci
ence
Sym
posi
um a
nd M
edic
al Im
agin
g C
onfe
renc
e, H
onol
ulu,
Haw
aii,
USA
, Oct
ober
27-
Nov
embe
r 3, 2
007. The γ-ray spectroscopy domain The γ-ray spectroscopy domain
The region of high excitation
energy
in heavy Λ-hypernucleicannot
be explored with
γ-spectroscopy
The region of high excitation
energy
in heavy Λ-hypernucleicannot
be explored with
γ-spectroscopyHyperball2
@ Tohoku Cyclotron
Jun 2005 FINUDA@ DAΦNE
FINUDA@ DAΦNE
8A.
Fel
icie
llo /
IEEE
Nuc
lear
Sci
ence
Sym
posi
um a
nd M
edic
al Im
agin
g C
onfe
renc
e, H
onol
ulu,
Haw
aii,
USA
, Oct
ober
27-
Nov
embe
r 3, 2
007. Parallel vs. serialParallel vs. serial
one-arm spectrometer →
small acceptance• ∆E ~ 4 MeV (FWHM)• ∆Ω ~ 110 msr
HPGe array →
large acceptance• ∆E ~ 1 ÷ 2 keV (FWHM)• ε
~ 7%
(@ 1 MeV)
HyperballProject
@J-PARC
10A.
Fel
icie
llo /
IEEE
Nuc
lear
Sci
ence
Sym
posi
um a
nd M
edic
al Im
agin
g C
onfe
renc
e, H
onol
ulu,
Haw
aii,
USA
, Oct
ober
27-
Nov
embe
r 3, 2
007.
Do HPGe crystals
work in (strong) magnetic field?
Penning effect? (sparks)Hall effect? (FET breakdown)
VEGA @ GSI
Experimental challengesExperimental challengesJRA6
11A.
Fel
icie
llo /
IEEE
Nuc
lear
Sci
ence
Sym
posi
um a
nd M
edic
al Im
agin
g C
onfe
renc
e, H
onol
ulu,
Haw
aii,
USA
, Oct
ober
27-
Nov
embe
r 3, 2
007.
Do HPGe crystals work in (strong) magnetic field?
Penning effect? (sparks)Hall effect? (FET breakdown)
To what extent the energy resolution is affected?
Experimental challengesExperimental challengesJRA6
12A.
Fel
icie
llo /
IEEE
Nuc
lear
Sci
ence
Sym
posi
um a
nd M
edic
al Im
agin
g C
onfe
renc
e, H
onol
ulu,
Haw
aii,
USA
, Oct
ober
27-
Nov
embe
r 3, 2
007. HPGe energy resolution in magnetic fieldHPGe energy resolution in magnetic field
NIM A 573 (2007) 410
VEGA @ GSI
Euroball
@ GSI
JRA6
19A.
Fel
icie
llo /
IEEE
Nuc
lear
Sci
ence
Sym
posi
um a
nd M
edic
al Im
agin
g C
onfe
renc
e, H
onol
ulu,
Haw
aii,
USA
, Oct
ober
27-
Nov
embe
r 3, 2
007.
Do HPGe crystals work in (strong) magnetic field?
Penning effect? (sparks)Hall effect? (FET breakdown)
To what extent the energy resolution is affected?
How to minimize
the mechanical interferences?
Experimental challengesExperimental challengesJRA6
20A.
Fel
icie
llo /
IEEE
Nuc
lear
Sci
ence
Sym
posi
um a
nd M
edic
al Im
agin
g C
onfe
renc
e, H
onol
ulu,
Haw
aii,
USA
, Oct
ober
27-
Nov
embe
r 3, 2
007.
Hyperball
FINUDA
An exacting integrationAn exacting integration
21A.
Fel
icie
llo /
IEEE
Nuc
lear
Sci
ence
Sym
posi
um a
nd M
edic
al Im
agin
g C
onfe
renc
e, H
onol
ulu,
Haw
aii,
USA
, Oct
ober
27-
Nov
embe
r 3, 2
007. The hyper-triple cluster concept designThe hyper-triple cluster concept design
thermal studies
mechanical
design
X –
COOLER II, AMETEC, ORTECJRA6
22A.
Fel
icie
llo /
IEEE
Nuc
lear
Sci
ence
Sym
posi
um a
nd M
edic
al Im
agin
g C
onfe
renc
e, H
onol
ulu,
Haw
aii,
USA
, Oct
ober
27-
Nov
embe
r 3, 2
007.
Geometrical acceptancereduced to 82%
Geometrical acceptancereduced to 82%
A look to the futureA look to the future
HPGe detectors
straw tubes
scintillator barrel
targets andμstrip detectors
drift chambers
straw tubes
targets andμstrip detectors drift chambers
HPGe detectors
scintillator barrel
24A.
Fel
icie
llo /
IEEE
Nuc
lear
Sci
ence
Sym
posi
um a
nd M
edic
al Im
agin
g C
onfe
renc
e, H
onol
ulu,
Haw
aii,
USA
, Oct
ober
27-
Nov
embe
r 3, 2
007. SummarySummary
strangeness nuclear physics still has a great discovery potential
explorative run on γ-ray spectroscopy
is feasible with:
present DAΦNE machineminor investment on FINUDA apparatus
DAΦNE luminosity upgrade will allow European Groups to carry on a significantscientific program