GET MEETING 2014 September , Saint-Avit Loisirs, FRANCE. G.Cardella for the FARCOS-EXOCHIM collaboration

Transcription

1 GET MEETING 2014 September , Saint-Avit Loisirs, FRANCE G.Cardella for the FARCOS-EXOCHIM collaboration

2 Farcos physics cases 1. Dynamics in heavy-ion collision (low and intermediate energies, stable beams and RIB) Femtoscopy: space-time probes of light particle emitting sources 2. Invariant mass spectroscopy (with stable and exotic fragmentation beams) Multi-particle decay correlations Cluster states (alpha-conjugate, boson condensates) Direct reactions

3 Technical planned features High energy and angle resolution (q,f) Modularity, Flexibility, Portability Geometry: coupling to 4π and Mag. Spectr. Electronics: integrated, reconfigurable Synergy with other highly segmented silicon detectors: shared technical efforts and physics cases with Must2, Trace, Other features from new electronics: Pulse-shape capabilities (Low identification thresholds) Digitalization of detector signals Wide dynamic range (correlation observables require light particle detection)

4 Wide dynamic range We need to see protons but also heavy ions at least up to Neon and this means to measure at least from 0.5 to 500 MeV For some particular experiment we should also go to GeV range (Obviously loosing protons) FAST-SLOW T4 Farcos Co60 Also for CsI(tl) sometime we need a good measurement of low energy g-rays And 400 MeV a-particles

5 FARCOS INFN-CATANIA Based on (62x64x64 mm 3 ) clusters 1 square (0.3x64x64 mm 3 ) DSSSD strips 1 square (1.5x64x64 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 Fully reconfigurable: more Si layers, neutron detection (future?)

6 Important step for the future Do you know that we got from INFN money to change CsI electronics for CHIMERA an we decided to use GET electronics now we already received 8 ASAD for this and we ordered 3 COBO and 1 Mutant card This year we presented to INFN a plan to build a total of 20 Farcos telescopes in 5 years We want to buy next year the electronics for these detectors - 15 ASAD cards - 5 Cobo - 1 Mutant Our project was approved and we will have money in January

7 Future experiments: Break-up -measurements 10 Be 6 He 4 He We are doing a check with published data measured around 30 MeV/A to verify calibrations and efficiency A new dedicated experiment with more complete angular coverage and better resolution to look for such exotic states in 10 Be but also in 16 C and all the other beams produced will be performed at the end of this year Subtracting uncorrelated background we see also 11.8 and perhaps 13.6 MeV excited levels G.Cardella ERICE 2014

8 Future experiment: the Pygmy resonance measurement Expected 68 Ni identification in FARCOS silicon detectors 68 Ni* n SPHERE RING 1-9 g-rays on the CsI(Tl) of the sphere CHIMERA Neutrons on the CsI(Tl) of CHIMERA rings covered by FARCOS G.Cardella ERICE 2014

9 Test with FARCOS and GET electronics: FPN Structure of the fixed pattern noise channels from the AGET description document The gain-2 input point used in the test

10 Test with FARCOS and GET electronics: need of FPN One can better understand the use of FPN channels looking to these signals. Here we show the signals that we can register from channels of ASAD with no input You can see that some structures are present in the signals, and that the shape of the noise is similar in all channels. This common noise can be therefore removed subtracting the FPN channels from the channels connected to detectors

11 Test with FARCOS and GET electronics: FPN effect This is the pulser spectrum obtained sending various values of pulser signals integrated without subtracting the fixed pattern noise to the baseline With a zoom on the peak around channel 2000 Doing, on the same set of data, the FPN subtraction, we get a much better result, comparable to results obtained with CHIMERA DAQ

12 CsI(Tl) test with GET: alpha signals Pulser equivalent 10 mv The signal amplitude is similar to a pulser 6 mv ( 1MW) the signals are converted at about channel 100 this means that we can see on CsI detectors signals up to 200 MeV alpha quite good for CsI first peak resolution: 180 KeV

13 CsI(Tl) test with GET: gamma - signals Co60 Am-Be

14 FARCOS DSSSD test with GET: alpha analysis Red line is the digitized alpha signal ( 100 MHz G-2Input ) after subtraction of the nearest FPN channel and baseline restore, in black the result of our digital filter ( triangular filter with 321 points points before and after the point to be averaged). After the filter we take the maximum of the signal and we plot on the histogram you have seen. The resolution of alpha spectra is a little worse than pulser of the order of 60 kev (first peak). We also did some test using the SK filter input trying filters at 1 micros and 500 ns but the result is rather equivalent, the digital filter that we do give the same result.

15 ENERGY On beam CsI-test Tandem beam 7 Li 27 MeV on various targets Preliminary results on shape analysis Rise time

16 On beam CsI-test Tandem beam 7 Li 27 MeV on various targets Same detector different ACQ ACQ GET Csi3-tel4 Li7+Au 27 MeV Li7+C-H 2 ACQ CHIMERA Csi3-tel4 Li7+Au 27 MeV Li7+C-H 2 Li7+C-D 2 Li7+C-D 2

17 DSSSD BEAM TEST - Fit of elastic scattering peak seen in all strips with Rutherford weighted angular distribution We extract an average energy resolution of about 0.3% (include electronic noise and beam spread) 27 MeV= 80 kev 7 Li + 12 C 27 MeV Grazing 8 D=70 cm s=0.3% We cut each strip in pixels we assume that in each pixel we see elastic scattering with Gaussian distribution around its average energy at the pixel angle - with weight given by Rutherford formula

18 DUALGAIN module to match dynamic range We need to use two channels of GET electronics for each strip and for some of the CHIMERA CSI Block scheme DUALGAIN module needed also to match CHIMERA/GET cable and to give the rigth offset to each channel We think to use VME mechanics putting in VME chassis 2 DUAL GAIN module for each ASAD card

19 Ackonwledgments L. Acosta 11, F. Amorini 1, L. Auditore 2,3, V. Baran 15, R. Bassini 7, C. Boiano 7, T. Cap 16, G. Cardella 4, A. Castoldi 7, M. Colonna 1, M. D Andrea 4, E. De Filippo 4, L. Francalanza 1,5, E. Geraci 4,5, R. Gianì 1,5, B. Gnoffo 5, C. Guazzoni 7, E. La Guidara 4, G. Lanzalone 1,10, I. Lombardo 13, G. Marquínez-Durán 11, T. Minniti 5, E. Morgana 2,3, E.V. Pagano 1,5, A. Pagano 4, M. Papa 4, E. Piasecki 17,18, S. Pirrone 4, G. Politi 4,5, F. Porto 1,5, L. Quattrocchi 2, F. Riccio 8, F. Rizzo 1, E. Rosato 13, P. Russotto 1,5, G. Saccà 4, A. Trifirò 2,3, M. Trimarchi 2,3, G. Verde 4, M. Vigilante 13, J. Wilczynski 19. 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, 15 Physics Faculty University of Bucarest, 16 Faculty of Physics University of Warsaw, Warsaw, Poland, 17 Heavy Ion Laboratory, University of Warsaw, Warsaw, Poland, 18 A. Soltan Institute for Nuclear Studies, Swierk/Warsaw, 19 Poland, National Center for Nuclear Research, Otwock-Swierk, Poland. THANK YOU FOR YOUR ATTENTION!!!