HAL Id: in2p3-00000738
http://hal.in2p3.fr/in2p3-00000738
Submitted on 5 Nov 2006
HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci- entific research documents, whether they are pub- lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.
L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
Observation of fission in Pb-Pb interactions at 158A GeV
M.C. Abreu, B. Alessandro, C. Alexa, R. Arnaldi, J. Astruc, M. Atayan, C.
Baglin, A. Baldit, L. Bardi, M. Bedjidian, et al.
To cite this version:
M.C. Abreu, B. Alessandro, C. Alexa, R. Arnaldi, J. Astruc, et al.. Observation of fission in Pb- Pb interactions at 158A GeV. Physical Review C, American Physical Society, 1999, 59, pp.876-883.
�10.1103/PhysRevC.59.876�. �in2p3-00000738�
Calorimeter
Preabsorber
ZDC
200 150
100 50
0 cm
40 20 0 cm
Carbon Absorber Collimator 7 subtargets
Multiplicity Detector
Electromagnetic
Fragment detector SiO2 fibers to fragment
detector’s PM
!#" $%#&' )(*+, .- /0$1 -2' 43 -5 -76982: ;
- 0 /$ 39<'% = > -?'5 -%$@ A3$AB C $ ? =3'%$EDCGF
2 mm
/ $ ('% (* 1- /$ G(*$ D ' AB # 3
$ '% -#DC*A1$ 0D=F46>$ '+(*$ ' 3 $+(B / % 3 $
$%" ,3 $ (4'% 5 A 3 3>3'$ DC - ' 5AB >-!+, 0 939$ >
ADC ch.
1 10 10 2 10 3
100 200 300 400 500 600 700 800 900 1000
Fig. 3a Author: Vercellin Physical Review C
Z eff dN/dZ eff
1 10 10 2 10 3 10 4
0 10 20 30 40 50 60 70 80 90
Fig.3b E.Vercellin Physical Review C
(b)
"!$#&%'(*)) ,+-'"*)./ 01"24365758-9 ,%:;=< >*- :.
0?@ A ;*< ,)B. C; :%:;*,DFEG $H*IJI0+K $2436575$K-G. CL() :.MK)= ; CNO,D
Z eff
hits/MD sector
0 2 4 6 8 10 12 14 16 18 20
10 20 30 40 50 60 70 80 90
$$ $+ $ (.' 7A $ (' 3 / " - 0 /0$ 3 /0$
"? 3 33 ! 30F
Z eff
< E ZDC
29000 29500 30000 30500 31000 31500 32000 32500 33000 33500
30 40 50 60 70 80 90
:@ #+ + 9$ (.'% $ - " A $ (
$ - 39 (*/0$ $+( F
0 0,2 0,4 0,6 0,8 1
0 2 4 6 8 10 12
Probability
208 Pb
207 Pb
206 Pb
tot Pb
target thickness x (mm)
%4$A5 A " $ ( 5-% -%! $-3 3 3 %-
// 39+32,(*/0$ $ (4' 7-% %' @'% 7 F ' 73 $ ()' 3
$A5 A% 3 %3 = 3C 3$ 3'%$EDC *!+ 3 F