0000000000267148
AUTHOR
Diego Barrientos
The GALILEO γ-ray array at the Legnaro National Laboratories
Abstract GALILEO, a new 4 π high-resolution γ -detection array, based on HPGe detectors, has been developed and installed at the Legnaro National Laboratories. The GALILEO array greatly benefits from a fully-digital read-out chain, customized DAQ, and a variety of complementary detectors to improve the resolving power by the detection of particles, ions or high-energy γ -ray transitions. In this work, a full description of the array, including electronics and DAQ, is presented together with its complementary instrumentation.
Effects of one valence proton on seniority and angular momentum of neutrons in neutron-rich Sb51122–131 isotopes
Background: Levels fulfilling the seniority scheme and relevant isomers are commonly observed features in semimagic nuclei; for example, in Sn isotopes (Z=50). Seniority isomers in Sn, with dominantly pure neutron configurations, directly probe the underlying neutron-neutron (νν) interaction. Furthermore, an addition of a valence proton particle or hole, through neutron-proton (νπ) interaction, affects the neutron seniority as well as the angular momentum. Purpose: Benchmark the reproducibility of the experimental observables, like the excitation energies (EX) and the reduced electric-quadrupole transition probabilities [B(E2)], with the results obtained from shell-model interactions for ne…
A capacitor selector tool for on-board PDN designs in multigigabit applications
This paper presents a capacitor selector software tool for a proper on-board Power Distribution Network (PDN) design in those high-speed applications which have strict requirements on voltage noise up to the first hundreds of megahertz. Current commercial tools for PDN design only offer a manual choice of the capacitor value and their number simulating the board impedance profile. This manual resolution becomes very hard when the design has high power consumption and noise requirements are very strict. The aim of this software is to solve a basic on-board PDN design minimizing the number of "change simulate-analyze" iterations that have to be carried out in the manual PDN design. This softw…
Lifetime measurements in Ti52,54 to study shell evolution toward N=32
Lifetimes of the excited states in the neutron-rich Ti-52,Ti-54 nuclei, produced in a multinucleon-transfer reaction, were measured by employing the Cologne plunger device and the recoil-distance D ...
Multiple register synchronization with a high-speed serial link using the Aurora protocol
In this work, the development and characterization of a multiple synchronous registers interface communicating with a high-speed serial link and using the Aurora protocol is presented. A detailed description of the developing process and the characterization methods and hardware test benches are also included. This interface will implement the slow control busses of the digitizer cards for the second generation of electronics for the Advanced GAmma Tracking Array (AGATA).
A New Front-End High-Resolution Sampling Board for the New-Generation Electronics of EXOGAM2 and NEDA Detectors
19th Real Time Conference (RT) -- MAY 26-30, 2014 -- Nara, JAPAN WOS: 000356458000028 This paper presents the final design and results of the FADC Mezzanine for the EXOGAM (EXOtic GAMma array spectrometer) and NEDA (Neutron Detector Array) detectors. The measurements performed include those of studying the effective number of bits, the energy resolution using HP-Ge detectors, as well as timing histograms and discrimination performance. Finally, the conclusion shows how a common digitizing device has been integrated in the experimental environment of two very different detectors which combine both low-noise acquisition and fast sampling rates. Not only the integration fulfilled the expected …
Performance of the Fully Digital FPGA-Based Front-End Electronics for the GALILEO Array
In this work we present the architecture and results of a fully digital Front End Electronics (FEE) read out system developed for the GALILEO array. The FEE system, developed in collaboration with the Advanced Gamma Tracking Array (AGATA) collaboration, is composed of three main blocks: preamplifiers, digitizers and preprocessing electronics. The slow control system contains a custom Linux driver, a dynamic library and a server implementing network services. The digital processing of the data from the GALILEO germanium detectors has demonstrated the capability to achieve an energy resolution of 1.53 per mil at an energy of 1.33 MeV.
Contributions to the new electronics of the AGATA gamma tracking detector. Design, implementation, test and integration of the digitizers control card
154 páginas. Tesis Doctoral del Departamento de Ingeniería Electrónica de la Universidad de Valencia.
A PCI Express optical link based on low-cost transceivers qualified for radiation hardness
In this paper we want to demonstrate that an optical physical medium is compatible with the second generation of PCI Express. The benefit introduced by the optical decoupling of a PCI Express endpoint is twofold: it allows for a geographical detachment of the device and it remains compliant with the usual PCI accesses to the legacy I/O and memory spaces. We propose two boards that can bridge the PCI Express protocol over optical fiber. The first is a simple optical translator while the second is a more robust switch developed for connecting up to four devices to a single host. Such adapters are already working in the control and data acquisition system of a particle detector at CERN and hen…
Evidence of octupole-phonons at high spin in 207Pb
A lifetime measurement of the 19/2 state in Pb has been performed using the Recoil Distance Doppler-Shift (RDDS) method. The nuclei of interest were produced in multi-nucleon transfer reactions induced by a Pb beam impinging on a Mo enriched target. The beam-like nuclei were detected and identified in terms of their atomic mass number in the VAMOS++ spectrometer while the prompt γ rays were detected by the AGATA tracking array. The measured large reduced transition probability B(E3,19/2→13/2)=40(8) W.u. is the first indication of the octupole phonon at high spin in Pb. An analysis in terms of a particle-octupole-vibration coupling model indicates that the measured B(E3) value in Pb is compa…
Pairing-quadrupole interplay in the neutron-deficient tin nuclei: First lifetime measurements of low-lying states in 106,108Sn
The lifetimes of the low-lying excited states 2(+) and 4(+) have been directly measured in the neutron-deficient Sn-106,Sn-108 isotopes. the nuclei were populated via a deep-inelastic reaction and the lifetime measurement was performed employing a differential plunger device. the emitted gamma rays were detected by the AGATA array, while the reaction products were uniquely identified by the VAMOS++ magnetic spectrometer. Large-Scale Shell-Model calculations with realistic forces indicate that, independently of the pairing content of the interaction, the quadrupole force is dominant in the B(E2; 2(1)(+) -> 0(g.s)(+)) values and it describes well the experimental pattern for Sn104-114 ; the B…
Fully digital FPGA-based Front-End Electronics for the GALILEO array
In this work we present the fully digital Front End Electronics (FEE) read out system developed for the GALILEO array. The system, developed in collaboration with the Advanced Gamma Tracking Array (AGATA) collaboration, is composed of three main blocks: preamplifiers, digitizers and preprocessing electronics. The slow control system contains a custom Linux driver, a dynamic library and a server implementing network services. The digital processing of the data from the GALILEO germanium detectors has demonstrated the capability to achieve an energy resolution of 1.53‰ at an energy of 1.33 MeV.
Isospin dependence of electromagnetic transition strengths among an isobaric triplet
*Aydın, Sezgin ( Aksaray, Yazar )
Graphical user interface for serial protocols through a USB link
In this work, a graphical user interface to communicate with three common serial protocols is presented. With one tool, the user may be able to control several evaluation boards from different manufacturers or evaluate and program integrated circuits of complex board prototypes. It provides a user-friendly interface to communicate with several chips using the USB port. The program has been used for the first stages in the qualification process of electronic boards for the Advanced GAmma Tracking Array (AGATA).
Development of the control card for the digitizers of the second generation electronics of AGATA
In this work, the features and development process of the novel control card for the digitizers of AGATA are presented. The board is part of the new hardware proposed for the electronic system of the experiment. In particular, the control card provides the sampling clock for the digitizers, contributes to the synchronization of the digital data and performs the slow control of its associated digitizer cards.
Low-lying electric dipole gamma-continuum for the unstable Fe-62,64 nuclei : Strength evolution with neutron number
6 pags., 4 figs.
Maximum Likelihood Estimation and non-linear least squares fitting with Levenberg-Marquardt Algorithm implementation in FPGA devices for high resolution hodoscopy
This work compares two possible solutions to achieve a higher resolution in a hodoscope based on Plastic Scintillating Fibers (PSF) by obtaining the point of maximum incidence of the radioactive beam. The two fitting algorithms proposed have been tested and implemented in Field Programmable Gate Array (FPGA) devices. On one hand, a probabilistic model based on the Maximum Likelihood Estimation (MLE) and on the other hand, non-linear least-squares fit with the Levenberg-Marquardt Algorithm (LMA).
AGATA-Advanced GAmma Tracking Array
WOS: 000300864200005
Isospin Properties of Nuclear Pair Correlations from the Level Structure of the Self-Conjugate Nucleus Ru88
The low-lying energy spectrum of the extremely neutron-deficient self-conjugate (N = Z) nuclide 88 44Ru44 has been measured using the combination of the Advanced Gamma Tracking Array (AGATA) spectrometer, the NEDA and Neutron Wall neutron detector arrays, and the DIAMANT charged particle detector array. Excited states in 88Ru were populated via the 54Fe(36Ar; 2n )88Ru fusion-evaporation reaction at the Grand Acc�el�erateur National d'Ions Lourds (GANIL) accelerator complex. The observed -ray cascade is assigned to 88Ru using clean prompt - -2-neutron coincidences in anti-coincidence with the detection of charged particles, con�rming and extending the previously assigned sequence of low-lyin…