FARCOS Femtoscope ancillary Array for Correlations & Spectroscopy G. Verde, INFN-Catania EXOCHIM collaboration, INFN (LNS-CT-MI-NA), Un. Messina, GANIL, GEM-UHU, open collaboration 1 Why need for a new project for the reaction program at INFN-CT and LNS? Farcos and present status (mechanics, electronics) NN2012

Physics topics 1.Heavy-ion collisions (stable and RI beams) –Dynamics (HBT, Femtoscopy) Low & Intermediate energies: fusion, fission, DIC, Symmetry energy, Emission time-scales, probes of reaction models –Multi-particle correlation spectroscopy (MPCS)  cluster states 2. Direct reactions with RIBs – Inverse and direct kinematics Nuclei close to drip lines

Chimera: isospin and dynamics 1m 1° 30° TARGET 176° Beam 1192 Si-CsI(Tl) Telescopes 18 rings in the range 1° ≤ θ ≤ 30° 17 rings in the range 30° ≤ θ ≤ 176° (sphere) High granularity and efficiency up to 94% 4π Z identification up to beam charge (ΔE-E) Z and A identification by ΔE-E up to Z ≤ 9 Z and A identification in CsI up to Z ≤ 4 Mass identification with low energy threshold (< 0.3 MeV/u) by ToF Z identification for particles stopping in Si (pulse shape)

Based on (62x64x64 mm 3 ) clusters 1 square (0.3x62x62 mm 3 ) DSSSD strips 1 square (1.5x62x62 mm 3 ) DSSSD strips 4 60x32x32 mm 3 CsI(Tl) crystals 4 CsI(Tl) crystals (3rd stage)DSSSD 1500 μm (2nd stage) DSSSD 300 μm (1st stage) Assembly cluster 132 channels by each cluster FARCOS TELESCOPE – phase 1 Fully reconfigurable (more Si layers, neutron detection, …)

+ Coincidence pairs + Uncorrelated pairs Deuteron-Alpha correlations Y 12 (q) Relevance of angular resolution Final-state interaction s Coulomb FSI: anti-correlation at small q values Nuclear FSI: correlation at q=42 and 84 MeV/c High angular resolution required:  Low q and resonances 1+R(q) q (MeV/c) deuteron-alpha 6 Li q (MeV/c)

Dedicated RIB experiment Multi-particle decay spectroscopy Using heavy-ion collisions as an explorative spectroscopy tool: several unbound species in one single experiment 8 B* 7 Be p 10 C* α p p α 12 C* α α α Expansion Not only EoS… p 5 Li* α

BC states in 12 C, 16 O, etc.???? A. Raduta et al., Phys. Lett. B705, 65, Ca+ 12 C, E/A=25 Chimera G.S. of 12 C  3 alpha Γ~ 7.5% direct three-body decay (BC?) …but more recently… J. Manfredi et al., PRC85, 2012!! Γ<0.5% direct three body decay! High resolution measurements (HiRA, pixelated detectors) can lead to totally different results…

FARCOS detectors Double-Sided Silicon Strip Detectors 300 μm and 1500 μm Capton cable and 2x32pin connectors Highly homogenous CsI(Tl) crystals Wrapping: 0.12mm thick white reflector +50μm aluminized Mylar. 2μm thick aluminized Mylar window at the entrance (0.29 g/cm 2 ) Read-out by photo-diodes (300μm)

Single cluster 4 CsI(Tl) crystals (3rd stage) DSSSD 1500 μm (2nd stage) DSSSD 300 μm (1st stage) photodiodes Mounting allows for addition of other detectors and neutron “transparency”

First prototype modules built 4 clusters expected to be ready by the end of 2012 March-April 2012

Geometric flexibility beam Cross geometry centered on the beam axis (10 clusters) Wall geometry placed at 45° from beam axis (9 clusters) 45° Transportability Modularity

Geometries Farcos Chimera Chimera rings Farco s Correlations in central collisions (cluster states, HBT, Asy-EoS) Correlations in Quasi-Projectile breakup Spectroscopy with radioactive beams

Projectile fragmentation beams Experiments with exotic beams Ex: Primary beam: 20 Ne E/A=45 MeV/A Production target: 9 Be (500  m) Fragments transported and tagged event-by-event by  E-ToF DSSD Tagging detector Di-proton decay from excited 18 Ne states G. Raciti et al., PRL (2008)

Primary beam : 18 O at 55 MeV/A, I~5x10 11 part/sec Production target: 9 Be (1.5 mm) Beam production 6He6He T (ns) 9 Li 12 B e 15 B 10 Be DE (MeV) Bρ=2.97 Tm I (kHz) 15 B B Be 1.5 optimized 9 Li2.0 8 Li B e 16 C 13 B 12 B e 9 Li 6 He 17 C 7 Li T (ns) DE (MeV) I (kHz) 16 C40 17 C 4 13 B23 11 Be 6 (optimized) 10 Be21 8 Li11 Energies: ~ MeV/A Momentum window  P/P <1% Bρ=2.71 Tm 11 B e 6 He 8 He 11 L i 14 Be DE (MeV) T (ns) Bρ=3.8 Tm I (hz) 14 Be4 11 Li20 9 Li40 8 He80 optimized 6 He980 G. Cardella et al.

Direct reactions with exotic beams FRIBS exotic beams 34 Ar + p  33 Ar + d Farcos ( 33 Ar residue) 33 Ar 34 Ar d Chimera (d) Day-1 experiment at LNS

Direct reactions in inverse kinematics Farcos Eden neutron array (Orsay) already installed at LNS Also for E sym (ρ) experiments Heavy residue (forward): Magnex Ligh charged particles: Farcos Neutron: EDEN, others

Required identification performances (Chimera-like)

Compact preamplifiers – Phase channels Hybrid charge preamplifiers in a volume of about 8cm x 10cm x 2mmm Low power consumption:~750 mW pwe 32 channels (simplify cooling operations) Rise-Time (pulser):~ 3-7 nsec for C input =0-100pF Energy resolution (pulser)~ 4.3 KeV for C input =0-100pF Available with several sensitivities (5, 10, 45, 100 mV/MeV…) INFN, Milano – C. Boiano, R. Bassini

First test with beams – July 2012 Chimera sphere p,α + p, d, CE/A=40, 80 MeVTransfer reactions CsI(Tl) uniformity Silicon resolution Integrating DAQ into Chimera system Rochester GANIL FARCOS

Electronics plans for phase 2 Pre-amplifiers with multiple gains and large dynamic range (MeV to GeV) Pulse-shape capabilities – Low identification thresholds for low energy experiments (Spiral2, Spes) Digitalization of detector signals Update possibilities – Solid angle increase – Coupling to different detectors (in different laboratories) 20

Neutron detection “Transparency” of materials and electronics boards to incoming neutrons Stacks of Silicon+Plastic for neutron detection – under study at the moment… P P P P P P P P P P Si ….. DSSSD1 DSSSD2 CsI(Tl) Electronics

FARCOS-collaboration PARTICIPANTS L. Acosta 1, T. Minniti 2,3, G. Cardella 4, G. Verde 4, F. Amorini 1, A. Anzalone 1, L. Auditore 2,3, M. Buscemi 1,5, A. Chbihi 6, E. De Filippo 4, L. Francalanza 1,5, E. Geraci 4,5, C. Guazzoni 7,8, E. La Guidara 4,9, G. Lanzalone 1,10, I. Lombardo 1,5, D. Loria 2,3, I. Martel 11, E.V. Pagano 1,5, A. Pagano 4, M. Papa 4, S. Pirrone 4, G. Politi 4,5, F. Porto 1,5, L. Quattrocchi 2,3, F. Rizzo 1,5, P. Russotto 1,5, A.M. Sánchez-Benítez 11, J.A. Dueñas 11, R. Berjillos 11, S. Santoro 2,3, A. Trifirò 2,3, M. Trimachi 2,3, M. Vigilante 13,14. INSTITUTIONS 1 INFN-LNS; 2 INFN- Gruppo Collegato di Messina; 3 Dip. Fis. Univ. Messina; 4 INFN- Sez. Catania; 5 Dip. Fis. e Astr. Univ. Catania; 6 GANIL, CEA-IN2P3-CNRS, Caen, France; 7 INFN- Sez. Milano; 8 Dip. Fis. Univ. Milano; 9 CSFNSM, Catania; 10 Univ. KORE, Enna, Italy; 11 Univ. de Huelva, Spain; 13 INFN- Sez. Napoli; 14 Dip. Fis. Univ. Napoli. 22