Isotope analysis in central heavy ion collisions at intermediate energies

Symmetry energy is a key quantity in the study of the equation of state of asymmetric nuclear matter. Heavy ion collisions at low and intermediate energies, performed at Laboratori Nazionali di Legnaro and Laboratori Nazionali del Sud, can be used to extract information on the symmetry energy coefficient Csym, which is currently poorly known but relevant both for astrophysics and for structure of exotic nuclei.Comment: 2 pages, 1 figure. Proceedings of 7th International Conference on Radioactive Nuclear Beams (RNB7), to be published in The European Physical Journal

GARFIELD + RCo Digital Upgrade: a Modern Set-up for Mass and Charge Identification of Heavy Ion Reaction Products

An upgraded GARFIELD + Ring Counter (RCo) apparatus is presented with improved performances as far as electronics and detectors are concerned. On one side fast sampling digital read out has been extended to all detectors, allowing for an important simplification of the signal processing chain together with an enriched extracted information. On the other side a relevant improvement has been made in the forward part of the setup (RCo): an increased granularity of the CsI(Tl) crystals and a higher homogeneity in the silicon detector resistivity. The renewed performances of the GARFIELD + RCo array make it suitable for nuclear reaction measurements both with stable and with Radioactive Ion Beams (RIB), like the ones foreseen for the SPES facility, where the Physics of Isospin can be studied.Comment: 13 pages, 19 figures - paper submitted to Eur. Phys. J.

Više-fragmentna tvorba u reakcijama 32S+58,64Ni NA 11 A MeV

The characteristic features of the 32S+58,64Ni reaction at 11 A MeV have been investigated to evidence the possible rise of multi-fragmentation processes at low excitation energies. The importance of such phenomena consists in the fact that they could represent the signature of a nuclear phase transition from a liquid to a gas region. Evidence of multi-fragment production is displayed by the present data; even if the yield of such events is compatible with the predictions of statistical models, the partition of the mass of the decaying system cannot be easily reproduced. Some preliminary indications of isospin effects are suggested by looking at the differences between the two reacting systems.Istraživali smo značajke reakcije 32S+ 58,64Ni na 11 A MeV radi pronalaženja mogućeg porasta više-fragmentnih procesa na nižim uzbudnim energijama. Važnost se tih pojava sastoji u tome što bi one mogle predstavljati znakove nuklearnog faznog prijelaza od tekućeg u plinsko stanje. Znakovi tvorbe više fragmenata vide se u dobivenim podacima; no čak ako je i prinos tih događaja u skladu s predviđanjima statističkog modela, razdioba mase sustava koji se raspada ne uspijeva se objasniti. Usporedba dviju reakcija ukazuje na moguće izospinske efekte

Energy measurement and fragment identification using digital signals from partially depleted Si detectors

A study of identification properties of a Si-Si DE-E telescope exploiting an underdepleted residual-energy detector has been performed. Five different bias voltages have been used, one corresponding to full depletion, the others associated with a depleted layer ranging from 90% to 60% of the detector thickness. Fragment identification has been performed using either the DE-E technique or Pulse Shape Analysis (PSA). Both detectors are reverse mounted: particles enter from the low field side, to enhance the PSA performance. The achieved charge and mass resolution has been quantitatively expressed using a Figure of Merit (FoM). Charge collection efficiency has been evaluated and the possibility of energy calibration corrections has been considered. We find that the DE-E performance is not affected by incomplete depletion even when only 60% of the wafer is depleted. Isotopic separation capability improves at lower bias voltages with respect to full depletion, though charge identification thresholds are higher than at full depletion. Good isotopic identification via PSA has been obtained from a partially depleted detector whose doping uniformity is not good enough for isotopic identification at full depletion.Comment: 13 pages, 10 figures 5 tables; submitted to European Physical Journal

Više-fragmentna tvorba u reakcijama 32S+58,64Ni NA 11 A MeV

The characteristic features of the 32S+58,64Ni reaction at 11 A MeV have been investigated to evidence the possible rise of multi-fragmentation processes at low excitation energies. The importance of such phenomena consists in the fact that they could represent the signature of a nuclear phase transition from a liquid to a gas region. Evidence of multi-fragment production is displayed by the present data; even if the yield of such events is compatible with the predictions of statistical models, the partition of the mass of the decaying system cannot be easily reproduced. Some preliminary indications of isospin effects are suggested by looking at the differences between the two reacting systems.Istraživali smo značajke reakcije 32S+ 58,64Ni na 11 A MeV radi pronalaženja mogućeg porasta više-fragmentnih procesa na nižim uzbudnim energijama. Važnost se tih pojava sastoji u tome što bi one mogle predstavljati znakove nuklearnog faznog prijelaza od tekućeg u plinsko stanje. Znakovi tvorbe više fragmenata vide se u dobivenim podacima; no čak ako je i prinos tih događaja u skladu s predviđanjima statističkog modela, razdioba mase sustava koji se raspada ne uspijeva se objasniti. Usporedba dviju reakcija ukazuje na moguće izospinske efekte

First direct measurement of the total cross section of 12C(alpha,gamma)16O

The total cross section of 12C(alpha,gamma)16O was measured for the first time by a direct and ungated detection of the 16O recoils. This measurement in inverse kinematics using the recoil mass separator ERNA in combination with a windowless He gas target allowed to collect data with high precision in the energy range E=1.9 to 4.9 MeV. The data represent new information for the determination of the astrophysical S(E) factor.Comment: 5 pages, 3 figures, 1 table, accepted for publication Eur.Phys.J. A (Online first available

Evaporation and fission decay of (132)Ce compound nuclei at E(x)=122 MeV: some limitations of the statistical model

Light charged particle (LCP) emission in the evaporation residue (ER) and fusion fission (FF) channels have been studied for the 200 MeV 32S + 100Mo reaction, leading to 132Ce composite nuclei at E x =122 MeV. The main goal was to study the decay of 132 Ce on the basis of an extended set of observables, to get insights on the fission dynamics. The proton and alpha particle energy spectra, their multiplicities, ER-LCP angular correlations, ER and FF angular distributions, and ER and FF cross-sections were measured. The measured observables were compared with the Statistical Model (SM). Using standard parameters, the model was able to reproduce only the pre-scission multiplicities and the FF and ER cross-sections. The calculation was observed to strongly overestimate the proton and alpha particle multiplicities in the ER channel. Disagreements were also observed for the ER-LCP correlations, the LCP energy spectra and the ER angular distribution. By varying the SM input parameters over a wide range of values, it is shown that it is not possible to reproduce all the observables simultaneously with a unique set of parameters. The inadequacy of the model in reproducing the ER particle multiplicities is also observed analysing data from the literature for other systems in the A ≈ 150 and E x ≈ 100−200 MeV region. These results indicate serious limitations about the use of the SM in extracting information on fission dynamics

ASPEK SOSIAL BUDAYA DALAM NOVEL MENAK JINGGO SEKAR KEDATON KARYA LANGIT KRESNA HARIADI (Kajian Sosiologi Sastra, Nilai Pendidikan Karakter, dan Relevansinya dengan Pembelajaran Sastra di SMA)

Penelitian ini bertujuan untuk (1) mendeskripsikan dan menjelaskan aspek sosial budaya masyarakat Kerajaan Majapahit yang terungkap dalam novel Menak Jinggo Sekar Kedaton karya LKH., (2) mendeskripsikan dan menjelaskan tanggapan pembaca di daerah Banyuwangi dan Surakarta terhadap novel Menak Jinggo Sekar Kedaton Karya LKH, (3) mendeskripsikan dan menjelaskan nilai-nilai pendidikan karakter yang terdapat dalam novel Menak Jinggo Sekar Kedaton Karya LKH, dan (4) mendeskripsikan dan menjelaskan relevansi novel Menak Jinggo Sekar Kedaton Karya LKH dengan Pembelajaran Sastra di SMA. Penelitian ini menggunakan metode penelitian kualitatif deskriptif dengan metode content analysis (analisis isi). Kegiatan yang dilakukan adalah membaca, mencermati, menafsirkan, dan menganalisis novel Menak Jinggo Sekar Kedaton karya LKH. Sumber data dalam penelitian ini adalah: (1) teks, novel Menak Jinggo Sekar Kedaton karya LKH; (2) catatan lapangan hasil wawancara yang terdiri atas dua bagian, yaitu bagian deskripsi dan bagian refleksi; (3) tanggapan pembaca terhadap novel Menak Jinggo Sekar Kedaton karya LKH dan (4) buku-buku literatur yang relevan. Teknik pengumpulan data dengan analisis dokumen dan wawancara secara mendalam. Trianggulasi dilakukan dengan trianggulasi sumber, metode, dan teori dengan pengecekan data dokumen dan hasil wawancara untuk mendapatkan simpulan yang sama. Data tersebut diperoleh dengan mengkaji novel Menak Jinggo Sekar Kedaton karya LKH melalui analisis isi, yaitu melakukan penafsiran terhadap teks untuk dipahami isinya. Teknik cuplikan yang digunakan adalah purposive sampling, sampel mewakili informasinya. Teknik analisis data yang digunakan adalah analisis model interaktif yang meliputi tiga komponen yaitu reduksi data, penyajian data, dan simpulan. Hasil penelitan dapat disimpulkan bahwa (1) aspek sosial budaya masyarakat Majapahit yang terungkap dalam novel meliputi: a) sistem religi, yakni kepercayaan agama Hindu dan Budha. Sistem nilai dan pandangan hidup, yakni berani mengucap sumpah, Hamukti Palapa. Upacara keagamaan yang terungkap yaitu Abiseka, Srada, Upacara Pitra Yadnya (Ngaben), Upacara keagamaan Pahargyan; b) sistem kemasyarakatan, terdiri dari sistem kekerabatan, assosiasi dan pekumpulan masyarakat, dan sistem kenegaraan; c) sistem pengetahuan terdiri dari pengetahuan musim, flora dan fauna, waktu, ruang, dan bilangan, dan perilaku antar sesama manusia; d) sistem bahasa, yaitu bahasa lisan dan bahasa tulisan Jawa Kuno; e) sistem kesenian yaitu lukis dan gambar, tata rias, bagunan, seni musik, dan kesusastraan; f) sistem mata pencaharian meliputi: bercocok tanam atau bertani, pegawai atau petugas pemerintah, nelayan atau perikanan; g) sistem peralatan hidup meliputi: alat transportasi, peralatan komunikasi, bentuk peralatan konsumsi dalam bentuk wadah, pakaian dan perhiasan, tempat berlindung dan perumahan, dan senjata; (2) tanggapan pembaca di daerah Banyuwangi dan Surakarta memberikan kontribusi yang positif dan menambah wawasan; (3) nilai pendidikan karakter yang terungkap yaitu 11 nilai; dan (4) memiliki relevansi terhadap pembelajaran sastra di SM