1 Possible “new” physics research using FAZIA-INDRAprePAC meeting Istituto Nazionale di Fisica Nucleare Possible “new” physics research using FAZIA-INDRA I. Lombardo and the NUCL-EX – INDRA – FAZIA Collaboration Dip. di Fisica, Università di Napoli Federico II Univ. Napoli Federico II and INFN Caen, 04/04/2017

2 I was right? Otherwise, let me sorry!The sense of the word «new» NEW  it is a «challenging» word! In this talk  I interpreted this word in the sense of: «Physical cases that could be explored by the FAZIA-INDRA detectors and that are different from the «classical» physical cases explored up to now by INDRA and FAZIA» i.e. Multifragmentation, Phase transition, Nuclear Dynamics, Nuclear Thermodynamics, Bimodality, Time scale emission chronology, etc Possible experiments in GANIL but also c/o other facilities (e.g. RIKEN,GSI, MSU…). Univ. Napoli Federico II and INFN – Napoli I was right? Otherwise, let me sorry!

3 SPECTROSCOPY OF LIGHT «EXOTIC»CASE I: SPECTROSCOPY OF LIGHT «EXOTIC» NUCLEI AND CLUSTERING Univ. Napoli Federico II and INFN – Napoli

4 Very RICH phenomenologyExotic structures in light nuclei Complexity of nuclear force  dominant phenomena of nucleon-nucleon correlations which determine a spatial re-organization of the nucleons in bounded sub-units  the constituent clusters. 12O 13O 14O 15O 16O 17O 18O 19O 20O 21O 22O 11N 12N 13N 14N 15N 16N 17N 18N 19N 20N 21N C 8C 9C 10C 11C 12C 13C 14C 15C 16C 17C 18C 19C 20C a B 8B 9B 10B 11B 12B 13B 14B 15B 17B 19B a Univ. degli Studi di Napoli Federico II & INFN - Napoli a Be 7Be 8Be 9Be 10Be 11Be 12Be 14Be linear chain 10Be,13-14C,16C(?),… Li 6Li 7Li 8Li 9Li 11Li He 3He 4He 6He 8He a H 1H 2H 3H a a a n core a a-cluster 8Be core neutron skin 8He,C neutron halo 6He,11Li,11Be dilute gas 12C 0+,16O,20Ne(?) Very RICH phenomenology

5 A simple case  model tuning!The 10Be case a a Ref. [1] AMD calculations  high deformation in GS [1]  Kp=0+ rotational band Ref. [3] High a-a cluster distance [3]  strong molecular structure  Kp=0+ molecular band built on the MeV [4] state Univ. degli Studi di Napoli Federico II & INFN - Napoli [1] Y. Kanada-En’yo, Phys. Rev. C 91, (2015) [2] D. Suzuki et al., Phys. Rev. C 87, (2013) [3] Y. Kanada-En’yo, J. Phys. G 24, 1499 (1998) [4] M. Freer et al., Phys. Rev. Lett. 96, (2006) A simple case  model tuning!

6 Rotational band in dimeric structureThe 10Be case a a J J(J+1) Ex (MeV) 6.18 2 6 7.54 4 20 10.15 [4] GS rotational band Kp=0+ molecular band Kp=1- rotational band J J(J+1) Ex (MeV) 2 6 3.37 4 20 11.78 [14]11 [2] (?) Univ. degli Studi di Napoli Federico II & INFN - Napoli [14] H.G. Bohlen et al., Phys. Rev. C 75, (2007) [1] Y. Kanada-En’yo, Phys. Rev. C 91, (2015) [2] D. Suzuki et al., Phys. Rev. C 87, (2013) [3] Y. Kanada-En’yo, J. Phys. G 24, 1499 (1998) [4] M. Freer et al., Phys. Rev. Lett. 96, (2006) J J(J+1) Ex (MeV) 1 2 5.96 6 6.26 3 12 7.73 4 20 9.27 5 30 11.8 42 15.3 [5] N. Soic et al., Europhys Lett. 34, 7 (1996) [6] M. Freer et al, Phys. Rev. C 63, (2001) [7] H.T. Fortune and B. Sherr, Phys. Rev. C 84, (2011) [8] N.I. Ashwood et al., Phys. Rev. C 68, (2004) [9] N. Curtis et al, Phys. Rev. C 64, (2001) [10] R. Wolsky et al., Phys. of Atom. Nucl. 73, (2010) [11] F. Kobayashi and Y. Kanada-en’yo, J. Phys.: Conf. Ser. 436, (2013) [12] S. Ahmed et al., Phys. Rev. C 69, (2004) [13] N. Curtis et al. Phys. Rev. C 73, (2006) Rotational band in dimeric structure

7 q* y How to measure the spin of unbound excited states?We can make use of angular correlations q* y A. Cunsolo et al, Phys. Rev. C 21 (1980) Rae & Bhowmik, Nucl. Phys. A 420 (1984) Marsh & Rae, Phys. Lett. B 153 (1985) Univ. degli Studi di Napoli Federico II & INFN - Napoli Making projections  oscillating functions proportional to [Pℓ(cosy)]2  determine ℓ A powerful way  hodoscope!

8 Too much discrepancies in the literature!Hot cases on clustering Beryllium isotopes: 10Be («molecular band»: firmer Jp assignments, 6+, other states?) 12Be: molecular band? Or not? 14Be: 6He+8He?  powerfulness of FAZIA Z.H. Yang, PRC 91 (2015) 6He+6He 4He+8He Charity et al Univ. Napoli Federico II and INFN – Napoli Too much discrepancies in the literature!

9 Neutron detection  branching ratios!Hot cases on clustering Carbon isotopes 13C  9Be+a decay. In closed kinematics: a+a+a+n 16C 12Be+a, 10Be+6He decay. AMD simulations: linear chain? 6He+10Be 16.505 4He+12Be 14.675 D. Dell’Aquila et al, PRC 95 (2016) Univ. Napoli Federico II and INFN – Napoli T. Baba, Y. Chiba and M. Kimura , Phys. Rev. C 90, (2014) Neutron detection  branching ratios!

10 FAZIA can make this job! FAZIA  structure of light nuclei Cluster 1Cluster structure of light radioactive nuclei (LISE, RIKEN, etc)  inelastic scattering followed by cluster channel break-up (xHe, xBe, xC…)  Excellent energy and isotopic resolution + reasonable angular resolution AZ Cluster 1 Cluster 2 d Fazia – 8 blocks Univ. Napoli Federico II and INFN – Napoli 10Be*  4He + 6He Example: 10Be structure above the cluster disintegration threshold FAZIA can make this job!

11 Useful coupling with INDRAClosed kinematics and the role of INDRA The coupling of FAZIA with INDRA can be important for this type of exp.! TARGET  proton (no internal structure, large NBU cross sections) Cryogenic target? Difficult! CH2 target, but carbon??? A possible solution: detect the recoil and make a Q-value spectrum to select the X+H break up collisions! INDRA  proton detection with large solid angle coverage Good determination of q* Univ. Napoli Federico II and INFN – Napoli Useful coupling with INDRA

12 PRODUCTION s(E) OF «SECONDARIES»: COSMIC RAY ASTROPHYSICSCASE II: PRODUCTION s(E) OF «SECONDARIES»: COSMIC RAY ASTROPHYSICS Univ. Napoli Federico II and INFN – Napoli

13 Large scale Galactic propertiesCosmic Rays elemental abundances Elemental abundances in SS and in CR Univ. Napoli Federico II and INFN – Napoli Elements very poorly abundant in the SS, but even 6(!) OoM more abundant in CR! Production by spallation of C, O, Ne, Fe, Ni by H (and He) interstellar medium (ISM). Large scale Galactic properties

14 Unstable nuclei  probe the GalaxyCosmic Rays as «messengers» Measurements of secondary stable and radioactive nuclei in CR basic information necessary to probe large-scale Galactic properties Diffusion coefficient, halo size, mechanisms and sites of CR acceleration Accuracy of nuclear cross sections  far behind the accuracy of CR measurements of the current missions. Typical uncertainties more than ∼ 50%  uncertainties in the propagation parameters  interpretation of data CODES: GALPROP by I.V. Moskalenko et al Univ. Napoli Federico II and INFN – Napoli LY Unstable nuclei  probe the Galaxy

15 A Nuclear help to Astrophysics!Isotopic ratios, halo size and ISM density Among the various isotopes useful to probe some characteristics of the Galaxy (ISM density, halo size etc)  radioactive isotope with lifetime (My) comparable to the formation and propagation in the Galaxy. The size of the galactic halo zh  from radioactive to stable isotopic ratios ISM density (atoms cm-3) JJ Connell, Astrophys. J. Lett. 501 (1998) i. V. Moskalenko et al, Proc. ICCR 2001 (kpc) Univ. Napoli Federico II and INFN – Napoli A detailed study of the errors associated with the propagation model is highly problematic and beyond the scope of this Letter (but see Waddington 1998 and references therein). The propagation uncertainties are dominated by uncertainties in the nuclear cross sections (DuVernois et al and references therein). A Nuclear help to Astrophysics!

16 Challenging measurements  absolute s(E)New measurements of cross sections Moskalenko & Mashnik, in the framework of GALPROP code, discuss this point GANIL GSI GANIL GSI Univ. Napoli Federico II and INFN – Napoli Both the possibilities (direct and inverse kinematics) are possible. I believe that direct kinematics is better, but  many blocks of FAZIA, perhaps INDRA In both cases  VAMOS or ALADIN (at GSI)  ds/dW near 0° complete angular distribution Challenging measurements  absolute s(E)

17 SUBTHRESHOLD PION EMISSIONCASE III: SUBTHRESHOLD PION EMISSION AND FIREBALL STUDIES Univ. Napoli Federico II and INFN – Napoli

18 At very low energies  play a role!Pion emission in HI collisions at Fermi energies At the end of the ‘70  discovered that in HI collision, pions can be emitted “sub-threshold” (i.e. below the E/A of a free NN scattering) Two alternative hypothesis: coherent effects versus NN scattering with Fermi momenta adding up At very low energies (20-30 A MeV)  pion reabsorption in the nuclear medium before to emerge: 𝑷 𝒂𝒃𝒔 𝑨 𝟏 , 𝑨 𝟐 , 𝝀 𝝅 =𝐞𝐱𝐩⁡{− <𝑹 𝑨 𝟏 , 𝑨 𝟐 > 𝝀 𝝅 } Univ. Napoli Federico II and INFN – Napoli Cassing [ZPA 329 (1988)] made geometrical estimates of lp is the average pion mean free path in NM At low energies (40, 50 A MeV) is (to my knowledge) still heavily UNCERTAIN! Nice way to estimate lp  to compare pion spectra with microscopic transport model calculations At very low energies  play a role!

19 Calculations on p emission  at 30-40 A MeVPion emission in HI collisions at Fermi energies At 94 A MeV 16O+27Al it was found lp = 3.7 fm from the analysis of p+ kinetic energy spectra. R. Barbera et al, Nucl. Phys. A 519 (1990) Pions are emitted by the fireball in very central events (b≈1.9 fm) and in a very short time scale (15 fm/c): perhaps still within the compression phase of the HIC Univ. Napoli Federico II and INFN – Napoli In more recent times (2014)  Hong & Danielewicz  pBUU calculations p+/p- kinetic energy ratio  sensitive to the Symmetry Energy stiffness Subthreshold energies  pions, nucleons, fragments: multiple-probes Calculations on p emission  at A MeV

20 How to detect pions? Pion emission in HI collisions at Fermi energiesEven the same pion reduced cross section at very low (= near 20, 30 A MeV) is still a mystery Under 54 A MeV the phase space is more and more closed  effective threshold for p production BUT events are seen down to 20 A MeV (in some case linked to the “pionic fusion”): coherent effect? Pseudo – cluster in nuclei? Fluctuations of momentum distributions? EXCLUSIVE measurements, i.e. in coincidence with fragments and LCP Univ. Napoli Federico II and INFN – Napoli Careful b selection; better volume definition of the FB source: number of nucleons giving rise to the pion baryonic density of the FB (Albergo method) temperature reached (by particle thermometers) How to detect pions?

21 A possible coupling with INDRA & FAZIA?Pion emission in HI collisions at Fermi energies Neutral pions: easier to be identified (EM shower + Lead glass calorimeter plane), but less interesting than charged pions Univ. Napoli Federico II and INFN – Napoli Charged pions: nice and “simple” idea (V. Bernard et al, NPA 423 (1984) Range telescope made by plastic scintillators Separate p+ / p- by delayed coincidence pulse analysis A possible coupling with INDRA & FAZIA?

22 OSCAR: A POSSIBLE «ANCILLARY»APPENDIX: OSCAR: A POSSIBLE «ANCILLARY» OF INDRA – FAZIA? Univ. Napoli Federico II and INFN – Napoli

23 Test and Characterization at LNS - INFNA new versatile hodoscope: OSCAR OSCAR: hOdoscope of Silicons for Correlations and Analysis of Reactions Silicon pads, 300 mm (HAM.) Charge PRE  22mV/MeV Two boards  plug and play Strip Si 20 mm (nominal!)  Micron Std. SSSSD  16 strip , 3 mm wide; mm interstrip Charge PRE, 16 ch. NET Inst. (45, 90 mV/MeV) Univ. Napoli Federico II and INFN – Napoli Front-End  Analogic Digital one Test and Characterization at LNS - INFN

24 Calculated with the real thickness of SSSSDIsotopic resolution and energy thresholds TEST of OSCAR at LNS: 40,48Ca+40,48Ca at 35 A MeV Isotopic identification up to Li Very low thresholds (≈ 1.2 A MeV) Ca+Ca a source Univ. Napoli Federico II and INFN – Napoli Thin dead layer (0.2mm) AFM measurements Good energy resolution  70 keV FWHM for 5-6 MeV a particles Calculated with the real thickness of SSSSD

25 Parameters to be taken under control!A critical point: the SSSSD thickness uniformity Map of the SSSSD thickness  new LNS facility a Source 241Am 2 mm collimator mobile support SSSSD Si + electronics a Univ. Napoli Federico II and INFN – Napoli High non-uniformity (with this peculiar pattern) silicon wafer cut (20 mm!) FUNDAMENTAL aspect  influence isotopic resolution Parameters to be taken under control!

26 QT investigation (barriers, N/Z, etc.)40,48Ca+40,48Ca at 35 A.MeV results Low energy part of LCP and fragment spectra isotopically resolved (H, He, Li, Be) Univ. Napoli Federico II and INFN – Napoli QT investigation (barriers, N/Z, etc.) 26

27 Signals of isospin diffusion40,48Ca+40,48Ca at 35 A.MeV results Low energy part of LCP and fragment spectra  QT emission 48Ca+48Ca 48Ca+40Ca Univ. Napoli Federico II and INFN – Napoli 40Ca+40Ca N/Z1 N/Z2 N/ZQP N/ZQT N/ZMV Signals of isospin diffusion 27

28 THANK YOU FOR YOUR ATTENTION!Unbound fragment emission: correlations Use of OSCAR for correlations  complex fragment emission Projectile Target Pre-equilibrium, stopping, compression Flow, expansion Fragmentation Secondary decays Univ. Napoli Federico II and INFN – Napoli Erel a+a correlation THANK YOU FOR YOUR ATTENTION! 28

29 Further Slides Univ. Napoli Federico II and INFN – Napoli

30 Nice granularities  30-40 cmGeometries and MC simulations TEST of OSCAR at LNS: 40,48Ca+40,48Ca at 35 A MeV OSCAR was placed at 102 cm from the target, qlab = 52o Univ. Napoli Federico II and INFN – Napoli 4 strip in one pad  geometrical overlap Exp. data  fragment AD in LAB Solid angles  MC simulations + cross check with Rutherford scattering Nice granularities  cm

31 … does the channeling play a role?A critical point: the SSSSD thickness uniformity Map of the SSSSD thickness  new LNS facility We can investigate how the thickness gradient of the large surface SSSSD influence the I. R. Mass spectra  from the DE-E line with an analytical method  Bethe-Bloch formula N. Le Neindre et al, NIM A 490 (2002) 251 Univ. Napoli Federico II and INFN – Napoli t/y Good mass resolution sA only if t/y < 0.3 mm/mm. Mandatory requirement! Energy loss effect, but … … does the channeling play a role?

32 Tilt is needed! Channeling effects on ultra-thin detectorsIn the literature  very few studies on channeling effects in ultra- thin Si detectors  important to prevent loss of energy resolution G. Thungstrom et al, NIM A 546 (2005) Channeling (higher residual energy) Si 14.5 mm a 241Am From the difference with respect to a purely gaussian trend:  channeled component about 15% Our SSSSD, 21 mm thick «pixel» Non channeled (gaussian) Univ. Napoli Federico II and INFN – Napoli Tilt is needed!

33 Further investigationsChanneling effects on ultra-thin detectors Estimate of the channeling effect in the SSSSD: 1) By subtraction of the gaussian component (quantitative, but difficulties  Bragg region) 2) By using the skewness g of residual energy spectra (qualitative) Univ. Napoli Federico II and INFN – Napoli G. Thungstrom et al, NIM A 546 (2005) Some dependence on the thickness: > thickness  > channeling But at very low thicknesses??? Quasi – flat behaviour? Further investigations

34 Thank you for your attention!Summary and Conclusions Hodoscopes  good candidates to be used as powerful ancillary detectors in a large variety of experiments OSCAR: a new low-threshold and high granularity, modular, hodoscope 20 mm mm Si Strip – Si pad detector, 5×5 cm2 area Test of the detector performances: mass and energy resolution Problems: gradient of thickness, channeling in ultra-thin detectors Results on QT emission in Ca+Ca collisions at 35 A.MeV 4He+4He correlations with OSCAR  powerful correlator properties Univ. Napoli Federico II and INFN – Napoli Thank you for your attention! 34

35 Applicazioni a SPES@LNLAlcuni risultati di Fisica – 2 Rapporti isotopici per il QT (selezioni in vpar)  isospin diffusion ISOBARIC RATIO 40Ca+40Ca 48Ca+40Ca 48Ca+48Ca Univ. Napoli Federico II and INFN – Napoli S. Albergo, S. Costa, E. Costanzo, A. Rubbino, Nuovo Cim A 89 (1985) Applicazioni a 35

36 Tests e caratterizzazioni ai LNS - INFNOverview di OSCAR OSCAR: Odoscopio di Silici per le Correlazioni e le Analisi di Reazioni Pads di Silici da 300 mm (Ham.) Preamplificatori di Carica 22mV/MeV Due schede  plug and play Strip Si da 20 mm (nominali!)  Micron sct. SSSSD  16 strip da 3 mm; mm interstrip Pre di carica a 16 vie NET Inst. (45, 90 mV/MeV) a source spectrum – 300 mm Univ. Napoli Federico II and INFN – Napoli Elettronica Front-End  analogica (per adesso) Tests e caratterizzazioni ai LNS - INFN