1. Second International Spes Workshop, LNL, 26 th - 28 th May 2014 Prompt collective oscillations with exotic beams Letter of intent for the SPES-ALPI facility S. Barlini from INFN-Fi and University of Florence Subscribers from: INFN (Fi, Mi, LNL, Bo, Ct, LNS), Italy LPC, Caen, France Daresbury, UK; NIPNE, Romania; Nevsheir University, Turkey; IFJ PAN Krakòw, Jagellonian Univ., Warsaw Univ., Silesian University Katovice, Poland; Ohio University, US R.Boskovic Institute, Zagreb, Croatia

2. Physics case The Dynamical Dipole Resonance (DDR) is a collective oscillation occurring at the beginning of the interaction between nuclei with different N/Z. The centres of mass of protons and neutrons don’t coincide and a dipole moment oscillation develops in the mean-field of the system, with emission of high energy gamma. Second International Spes Workshop, LNL, 26 th - 28 th May 2014 N 1 /Z 1 N 2 /Z 2 Dynamical Dipole γ emission from a not equilibrated source γ γ Earlier stage of nuclear interaction Isospin equilibration The damping of the DD emission is connected to the dynamical evolution of the system towards the isospin equilibration.

3. Main features of the DDR emission The DDR yield grows as a function of the charge-asymmetry of the two reaction partners. Usually, the DDR is studied as a function of the initial dipole moment (D 0 ) of the system, defined as The gamma energy of DDR is shifted to lower values (around 10 MeV) with respect to GDR emission (emitted when the system is equilibrated), as a consequence of the larger deformation of the system N/Z dependence DDR occurs typically at beam energies in the range around 6-12AMeV: o below 6AMeV the acceleration felt by the charge distribution is too small o beyond 12AMeV quenched oscillations and high pre- equilibrium particle emission Energy range 6-12AMeV DDR produces gamma’s with angular distribution peaked perpendicularly to the interaction axis of the two nuclei Second International Spes Workshop, LNL, 26 th - 28 th May 2014 Physics case

4. Considering the connection of the DDR emission with the dynamic of the heavy ion collisions, the estimation of the total yield of the oscillation can be compared to the predicted values by dynamical model (as SMF) to constrain the stiffness of the Symmetry energy assumed in the calculations for the EOS. Physics case Second International Spes Workshop, LNL, 26 th - 28 th May 2014 D.Pierroutsakou et al. PRC80, 024612(2009) E.Giaz al., PLB submitted 36 Ar+ 96 Zr and 32 S+ 100 Mo 16 O+ 112 Sn Asy-stiff Asy-soft Asy-stiff More data are needed

5. The “standard” technique to disentangle the DDR emission is the comparison between two reactions (one charge symmetric system with small D 0 and one charge asymmetric system with big D 0 ) producing the same CN. Second International Spes Workshop, LNL, 26 th - 28 th May 2014 The proposed experiments: CN reactions

6. Energy range 6-12 AMeV SPES beam (UCx 200 µA) 141 Cs : 2.6* 10 8 pps 142 Cs : 2.69* 10 7 pps 90 Kr : 8.74* 10 7 pps 132 Sn : 3.11* 10 7 pps 132 Sn: the “monster” resonance Possible DDR dependence on the mass asymmetry between projectile and target (same initial dipole, obtained with a mass asymmetric and symmetric system to test possible difference in the dynamics of interaction) New subject The proposed experiments: CN reactions

7. SMF prediction for some of the proposed system (by M. Colonna) Isospin asymmetric: large initial dipole DDR energy depends on the oscillation frequency Time evolution of the dipole moment Isospin symmetric: no initial dipole Bremsstrahlung quantitative formula:

8. The experimental apparatus: some requirements Evaporation Residue (and Fission Fragments) Detection LCP for pre- equilibrium estimation Gamma detector PPAC Phoswich detectors RCo detector Mass spectrometer …. GARFIELD FAZIA FARCOS TRACE... HECTOR SERPE MEDEA PARIS LaBr … It is important to detect at the same time the ER, LCP and gamma rays (with ER- gamma and ER-LCP coincidences). A strong collaboration among the different experimental groups interested in this type of experiments should start in order to find what is the best and most feasible solution that can be implemented.

9. S.Barlini a, G. Casini a, M. Bini a, M. Bruno b, M. Cinausero e, M. D'Agostino b, D. Fabris e, N. Gelli a, F. Gramegna e, T. Marchi e, L. Morelli b, A. Nannini a,A. Olmi a, S. Valdre a, G. Pasquali a, S. Piantelli a, G. Poggi a, R. Alba g, C. Maiolino g, D. Santonocito g, G. Prete e, A. Bracco c, F. Camera c, O. Wieland c, A.Giaz c, F.L.C.Crespi c, G.Benzoni c, S.Leoni c, B.Million c, N.Blasi c, M. Ciemala d, B. Fornal d, M. Kmiecik d, A. Maj d, K. Mazurek d, B. Wasilewska d, C.Borcea i, M. Parlog lp,i, M. Degerlier f, T. Kozikj u, A. Kordyasz wa, P. Kulig ju, Z. Sosin ju, A. Wieloch ju, T. Twarog ju, D. Sierpowski ju, M. Kajetanowicz ju, J. Lukasik d,K. Korcyl d,B. Klos si, S. Kowalski si, A. Grzeszczuk si,W. Zipper si, M. Chartier h, R. Lemmon h, Z. Basrak z, M. Milin z, N. Soic z, S. Szilner z, A. Voinov oh, M.Colonna g, M.Di Toro g, C.Rizzo g, V.Baran i a INFN, Sezione di Firenze and Dipartimento di Fisica dell'Università, Firenze, Italy b INFN, Sezione di Bologna and Dipartimento di Fisica dell'Università, Bologna, Italy c INFN, Sezione di Milano and Dipartimento di Fisica dell'Università, Milano, Italy d H. Niewodniczanski Institute of Nuclear Physics PAN, Krakow, Poland e INFN, Laboratori Nazionali di Legnaro, Italy f Nevsehir University of Science and Art Faculty Physics Department, Nevsheir, Turkey g INFN, Laboratori Nazionali del Sud, Catania, Italy h Daresbury Laboratory, Cheshire, United Kingdom i NIPNE-HH and Bucharest University, Romania wa University of Warsaw, Poland ju Jagellonian University, Krakow, Poland si Silesian University, Katowice, Poland oh Ohio University, US lp LPC, Caen, France z R. Boskovic Institute, Zagreb, Croatia