The AGATA Demonstrator at LNL: Status of the installation andscientific programme.A.Gadea CSIC-IFIC / INFN-LNLon behalf of E.Farnea (new local responsible) and the AGATA Collaboration
The AGATA DemonstratorObjective of the final R&D phase 2003-2008 1 symmetric triple-cluster5 asymmetric triple-clusters 15 ×36-fold segmented crystals 540 segments 555 high resolution digital-channels Eff. 3 – 8 % @ Mg = 1 Eff. 2 – 4 % @ Mg = 30 Operate in real time ACQ,Pulse Shape Analysis andg-ray Tracking Hosting sites: LNL 2008 GANIL 2010 GSI 2012
MC simulations by E.Farnea The AGATA Demonstrator performance figures b > 0 AGATA D. LNL 13.5 cm AGATA D. LNL 13.5 cm AGATA radius 23.5 cm AGATA radius 23.5 cm b = 0
AGATA Demonstrator Experimental Program 2008 LNL6TC 2010 GANIL/SPIRAL≥8TC 2012 GSI / FRS ~15TC AGATA D. @ FRS AGATA D. + PRISMA AGATA D. + VAMOS AGATA D. ≥8TC EXOGAM 8 seg. Clovers Total Eff. > 10% Setup works also as Compton Polarimeter Eff (%) vs. distance AGATA radius 23.5 cm b = 0 b = 0.5 AGATA D. LNL 13.5 cm 6%
Schematics of the mounting frame with 15 triple clusters AGATA Demonstrator – PRISMAPRISMA: large acceptance spectrometer for binary reactions
Installation of the AGATA Demonstrator at LNL Currently: Installation of basic infrastructures at LNLJuly: Installation & start commissioning DSSJuly-August: first tests with first AGATA TC
AGATA Demonstrator mechanics: from the AGATA Flange to the full structure.(Design: STFC Daresbury, Construction: INFN-Padova, Milano, LNL) 3 mounting attempts and 2 survey expeditions to reach acceptable tolerances Very strict tolerances for construction and mounting.(STFC) STFC Laser Tracker
Base and Intermediate frames AGATA Demonstrator support frame.(Design: STFC Daresbury, Construction: INFN-LNL and Padova,) Flange shell Frame with LN2 Bracket Flange shell Frame
Mounting the Flange shell in the Frame.(STFC Daresbury, INFN-Padova, Milano, LNL, GANIL)
Flange Shell Mounting Survey Results (STFC Daresbury, INFN-Padova, Milano, LNL, GANIL) Before mounting the shell in the frame: all points within 0.4 mm Model with the projection lines to the center After mounting the shell in the frame: all point within 0.5 mm Full support structure aligned to reaction chamber and target position
AGATA Demonstrator cryogenic infrastructures (INFN-LNL and INFN-Padova) Distribution and collector manifolds of-line tested, installed in the LN2 cryogenic line and commissioned.
AGATA Demonstrator cryogenic infrastructures (INFN-LNL and INFN-Padova) Evacuation line and evaporator for the LN2 overflows: problems solved, all parts mounted and tested.
DSS, Electronics and DAQ Infrastructures (LNL, Padova, CSNSM, IPNO, IPHC, Saclay, Daresbury, Liverpool, GSI, Jyvaskyla) On-board DSS & Digitizers Detectors Infrastructure installation ongoing PSA and DAQ Pre-processing 75m Optical fibres
BEAM AXIS Angular Range For The AGATA DEMONSTRATOR- PRISMA Setup q Distance target-AGATA ~14cm (efficiency ~6%) 58° to 130° fix 37° and 0° Distance target-AGATA ~23cm (efficiency ~3%) 38° to 130° fix 21° and 0° DEMOSTRATOR-PRISMA AXIS Design Engineer: Rob Griffiths Project Engineer: John Strachan STFC Daresbury Laboratory
AGATA Demonstrator – PRISMA reaction chamber and beam-line.(Construction: INFN-Milano, LNL) Low g- absorption reaction chamber Telescopic Beam-line Expansion Beam-Dump Ready to host DANTE
Next in programme for the installation • July • installation of cooling manifold in the Digitizer racks • final arrangement of optical fibers and cables • test of the DSS Low Voltage power supply prototype • Installation of the security appliances of the setup • test of the DSS Power Supply and Autofill controls • test on-site with the AGATA Digitizers • installation of DAQ will continue • probable arrival of the first TC to LNL • August-September • test of the detector mounting mechanics (to be programmed) • commissioning DSS • October • first on-site electronics + DAQ test
· · · · · · · · g AGATA DEMONSTRATION Highly segmented HPGe detectors NOVEL PRE-AMPS Identified interaction points Reconstruction of interaction tracks (tracking algorithmson interaction points)DAQ TRACKING-FARM (x,y,z,E,t)i Pulse Shape Analysisto de-convolute therecorded wavesDAQ PSA - FARM Synchronized digital electronics record and process the segment signalsDIGITIZERS +PRE-PROCESSING On-line reconstruction of g-rays
Commissioning Preliminary Plan (next plenary session!) The earliest possibility to run in-beam tests is Dec.2008 - Phase 0: commissioning with radioactive sources starting when detectors and electronics are available (even partially).- Phase 1: easy test with tandem beams with no ancillary detectors. Radiative capture or fusion-evaporation reactions with light targets in inverse kinematics.- Phase 2: test with a “simple” ancillary detector with limited number of parameters (DANTE). Coulomb excitation reactions with medium mass beams (A<100) in inverse kinematics.- Phase 3: test with PRISMA with multi-nucleon transfer reactions and at high multiplicity with appropriate ancillaries.
Scientific programme: Grazing reactions transferring several nucleons: evolution of magic numbers and collectivity in n-rich nuclei, but not only... neutrons protons Proton drip-line More than 20 LoI: Highly Excited Collective Modes.Proton rich mirror nuclei populated by transfer reactions.Superdeformed states in A~40 proton-rich nuclei. Neutron drip-line Order-Chaos transition in Warm rotating nuclei. Evolution of collectivity and Dynamical Symmetries in the rare earthsMix-symmetry statesQuenching of the N=82 shell gap in n-rich nucleiN=50 shell gap: lifetime, and excited statesSpectroscopy and lifetimes in the new region of deformation n-rich A~60, N~40 nucleiLifetimes in the region of the island of inversion
Collective modes in the continuum 2 1 3 g-arrays • Warm Rotation Exotic beams 2Giant Resonances 3Pygmy resonances PHASE SPACE Spin,Temperature, Isospin Collective Rotation- Order-to-Chaos TransitionCN reactions and Deep-Inelastic collissionsCollective Vibrations- Prompt dipole emission CN reactions- Highly excited/Pygmy states in n-rich nuclei Deep-Inelastic Collisions- Giant Quadrupole ResonanceInelastic Scattering G. Benzoni, N. Blasi , A. Bracco, S. Brambilla, F. Camera, A. Corsi, F.C.L. Crespi, S. Leoni, B. Million, D. Montanari, O. Wieland, et al.
GXPF1 interaction neutrons in g9/2 N=20,N=50 and N=82 Shell Gaps Tensor interaction between proton and neutron orbitals N=20: 32Mg Island of inversion (due to residual interaction) B(E2): GANIL, RIKEN, REX-ISOLDE, NSCL T. Otsuka et al., PRL 95, 232502 (2005) Contribution of tensor interaction to the monopole term in N=20, 50 and 82 C.Petrache, et al., E.Sahin, et al., R.Chapman et al., G. Duchêne et al., F.Azaiez et al., A.Gadea et al.
New magic numbers and shape evolution pf7/2 g9/2 40 np3/2 p1/2f5/2 nf7/2 32 Shell evolution produces new magic numbers and regions of deformation: N=32 shell closure for Z~20, N40 Z<28 transitional and deformation Shape evolution in nuclei Z>28 with 40<N<50 J.J.Valiente-Dobón et al., D.Mengoni et al., S.M.Lenzi et al., A. Görgen et al.,A.D.M.Cullen et al.,
Symmetries and shape phase-transitions 152Sm 134Ba F. Iachello, Phys. Rev. Lett. 85 (00)3580, Phys. Rev. Lett. 87 (01) 052502 Critical point symmetries in neutron-rich nuclei.Evolution of symmetries/shapes with angular momentum. Shape stability for axial rotors. Mixed-symmetry states. O. Möller et al., N. Pietralla etal., D.Tonev et al., J.Nyberg et al., J.J.Valiente-Dobón et al.
neutrons protons High-spin and exotic shapes • Exotic deformations in actinide nuclei. • Highly collective rotational structures (equivalent to SD) in light nuclei populated by coulex. Superdeformation Hyperdeformation in n-rich nuclei. Interplay between singe-particle and collective degrees of freedom. • Quadrupole – octupole collectivity • Quadrupole measurements / Shape identification A. Maj, P. Napiórkowski, F. Azaiezet al., J. Ollier, N. Pietralla et al., J.Simpson et al., J. F. Smith et al., A. Görgen et al.,
q IC Energy [a.u.] TRUE RECOIL VELOCITY+ TRAJECTORY IN DIPOLE+ TOTAL ENERGY rv [a.u.] Z IC Energy [a.u.] IC Range [a.u.] Tracking on PRISMA v/c BEAM LIKE true recoil velocity TARGET LIKE A/q trajectory in dipole MWPPAC DIPOLE IONIZATION CHAMBER 5‰ Energy resolution MCP Start Detector A MCP-MWPPAC DTOF=0.5 ns S.Beghini et al. NIM A551, 364 (05) G.Montagnoli et al. NIM A547, 455 (05)
v/c distribution AGATA Demonstrator at PRISMA Efficiency at 1MeV: ~6% at 14cm Peak/Total: ~50% Angles covered: from ~135o to 180o FWHM, b~10%, 1MeV: <4 keV Simulation with full PRISMA reconstruction by E.Farnea FWHMCLARA ~7 keVAD 24 ~2.6 keVAD 14 ~3.3 keV Eg = 1 MeV b ~ 8.9%
Differential RDDS Measurement in the 48Ca region with CLARA D.Mengoni, J.Valiente, A.Gadea, A.Dewald Differential Plunger for angles ≠ 0o 48Ca 310MeV + 208Pb (1mg)Degrader 4mg Mg
Comparison between the Diff.plunger lifetime experiment performed with CLARA and with the AGATA D. Plunger – AGATA 14cm After Degrader Before Degrader 48Ca 310MeV + 208Pb d=2200mm FWHM ~ 3.5 keV FWHM ~ 6 keV Complete CLARA-PRISMA M-C simulation by D.Mengoni d=1240mm T1/2 ~100ps d=300mm
Outlook: • LNL is doing a consistent effort to have the acceleration complex upgraded for the arrival of the AGATA Demonstrator (AD). A new ECR source is presently being installed . • The basic infrastructures for AD will be completed by summer 2008 and, the first tests with an AGATA TC are expected between summer and October. • For the physics campaign, following the Demonstration, the AD will provide experimental capabilities beyond CLARA. • Installation only possible with all the AGATA collaboration working groups, THANK YOU!