| 1. |
- Avdeichikov, Vladimir, et al.
(författare)
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Analysis of charged particle emission sources and coalescence in E/A=61 (MeVAr)-Ar-36+Al-27, Sn-112 and Sn-124 collisions
- 2004
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Ingår i: Nuclear Physics, Section A. - : Elsevier BV. - 0375-9474. ; 736:1-2, s. 22-38
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Tidskriftsartikel (refereegranskat)abstract
- Single-particle kinetic energy spectra and two-particle small angle correlations of protons (p), deuterons (d) and tritons (t) have been measured simultaneously in 61 A MeV Ar-36 + Al-27, Sn-112 and Sn-124 collisions. Characteristics of the emission sources have been derived from a "source identification plot" (beta(source)-E-CM plot), constructed from the single-particle invariant spectra, and compared to the complementary results from two-particle correlation functions. Furthermore, the source identification plot has been used to determine the conditions when the coalescence mechanism can be applied for composite particles. In our data, this is the case only for the Ar + Al reaction, where p, d and t are found to originate from a common source of emission (from the overlap region between target and projectile). In this case, the coalescence model parameter, (p) over tilde (0)-the radius of the complex particle emission source in momentum space, has been analyzed.
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| 2. |
- Avdeichkov, V, et al.
(författare)
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Energy calibration of CsI(T1) scintillator in pulse-shape identification technique
- 2003
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Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 501:2-3, s. 505-513
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Tidskriftsartikel (refereegranskat)abstract
- A batch of 16 CsI(TI) scintillator crystals, supplied by the Bicron Company, has been studied with respect to precise energy calibration in pulse-shape identification technique. The light corresponding to pulse integration within the time interval 1.6-4.5 mus (long gate) and 0.0-4.5 mus (extra-long gate) exhibits a power law relation, L(E, Z, A) a1 (Z, A)Ea2(Z-4), for (1.2.3) H isotopes in the measured energy range 5-150 MeV. For the time interval 0.0-0.60 mus (short gate), a significant deviation from the power law relation is observed, for energy greater than similar to30 MeV. The character of the a2(p)-a2(d) and a2(p)-a2(t) correlations for protons, deuterons and tritons, reveals 3 types of crystals in the batch. These subbatches differ in the value of the extracted parameter a2 for protons, and in the value of the spread of a2 for deuterons and tritons. This may be explained by the difference in the energy dependence of the fast decay time component and/or by the difference in the light output ratio of the fast/slow components. An accuracy well inside 1.0% is achieved in the energy calibration of the CsI(TI) crystals by using the DeltaE(Si) E(CsI(Tl))/PMT method. The batch of 16 CsI(TI) crystals is utilized to measure the correlations of light charged particles produced in E/A = 61 MeV, (36)Arinduced reactions. The preliminary correlation functions for two protons with small relative momenta are presented. (C) 2003 Elsevier Science B.V. All rights reserved.
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| 3. |
- Ghetti, Roberta, et al.
(författare)
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Calibration of a neutron time-of-flight multidetector system for an intensity interferometry experiment
- 2004
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Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002. ; 516:2-3, s. 492-501
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Tidskriftsartikel (refereegranskat)abstract
- We present the details of an experiment on light particle interferometry. In particular, we focus on a time-of-flight technique which uses a cyclotron RF signal as a start and a liquid scintillator time signal as a stop, to measure neutron energy in the range of En approximate to 1.8-150 MeV. This dynamic range (up to 300 ns) is much larger than the beam bunch separation (54 ns) of the AGOR cyclotron (KVI). However, the problem of a short burst period is overcome by using the time information obtained from a fast projectile fragment phoswich detector. The complete analysis procedure to extract the final neutron kinetic energy spectra, is discussed. (C) 2003 Elsevier B.V. All rights reserved.
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| 4. |
- Ghetti, Roberta, et al.
(författare)
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Chronology of neutron, proton and deuteron emission in intermediate energy heavy ion reactions
- 2004
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Ingår i: Nuclear Physics, Section A. - : Elsevier BV. - 0375-9474. ; 734, s. 597-600
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Tidskriftsartikel (refereegranskat)abstract
- The CHIC Collaboration has performed a series of fermion interferometry experiments to study the space-time evolution of the emission sources in intermediate energy heavy ion reactions. Correlation functions of non-identical particles have allowed us to extract model independent information on the sequence of emission (chronology) of the particles. In this contribution, we discuss the order of emission of neutrons, protons and deuterons from the E/A = 61 MeV Ar-36 + Al-27, Sn-112 and Sn-124 reactions.
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| 5. |
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| 6. |
- Ghetti, Roberta, et al.
(författare)
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Chronology of particle emission from the E/A=61 MeV Ar-36+Al-27 reaction
- 2003
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Ingår i: Physical Review Letters. - : American Physical Society. - 1079-7114 .- 0031-9007. ; 91:9: 092701
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Tidskriftsartikel (refereegranskat)abstract
- The emission time chronology of neutrons, protons, and deuterons from the E/A=61 MeV Ar-36+Al-27 reaction is deduced from two-particle correlation functions.
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| 7. |
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| 8. |
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| 9. |
- Ghetti, Roberta, et al.
(författare)
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Isospin effects in two-particle correlation functions: A probe for the isospin dependence of the nuclear equation of state
- 2005
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Ingår i: Nuclear Physics, Section A. - : Elsevier BV. - 0375-9474. ; 752:Part 2, s. 480-483
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Tidskriftsartikel (refereegranskat)abstract
- Small-angle two-particle correlation functions, involving neutrons and protons, have been measured for E/A = 61 MeV Ar + Sn-112,Sn-124 collisions, i.e. systems similar in size but with different isospin asymmetry. The correlation strength of neutron-proton (np) and proton-proton (pp) pairs is stronger for the more neutron-rich system, indicating a shorter average emission time for this system. Comparisons with isospin-dependent BUU transport model simulations are presented, and their implications for the density dependence of the nuclear symmetry energy are discussed.
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| 10. |
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