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CHIMERA is the only 4[pi]-multidetector, used in intermediate nuclear physics experiments, able to perform mass identification of the reaction products. To this purpose, it employs time of flight measurements done with traditional time to digital converters. In order to improve the resolution in mass identification, we have applied digital signal processing to time of flight measurements. This paper presents the methodology for data analysis, the adopted algorithms and the results obtained at different sampling frequencies (mass identification up to A = 33 for the reaction products produced by a 20.5 MeV/u [sup.20]Ne beam on [sup.27]Al target). Index Terms--Mass identification, nuclear measurements, nuclear physics, online digital signal processing, time of flight measurement.

The digital pulse shape data acquisition (DAQ) system used by the large area telescopes of the 4[pi]-multidetector CHIMERA requires transferring large amount of data to the computer. This is necessary so that the same information can be extracted from the detector pulses as in previous analog based systems. To overcome this problem, we have used a sampling ADC-board equipped with two TigerSHARC digital signal processors. The board receives the data and reconstructs the event parameters online. The data volume is significantly reduced by transmitting to the DAQ only the reconstructed event parameters. Index Terms--Digital signal processors, mass and charge identification, nuclear measurements, nuclear physics, online and on-board digital signal processing.

The capability of digital pulse shape technique to acquire data from CHIMERA detection cells (Si-CsI(TI) telescopes) has been evidenced in our previous works. We have now applied this technique to the charge discrimination of the products stopped in the silicon detectors. Large area totally depleted CHIMERA planar silicon detectors (5 cm x 5 cm area, 300/[micro]m thick) in both rear and front side injection have been used. In preliminary tests full charge identification for the reaction products up to Z = 11 have been obtained for products both crossing ([DELTA]E-E technique) and stopping in the silicon detector, using a 21 MeV/u [sup.20]Ne beam at the LNS Superconducting Cyclotron in Catania. The quality of the obtained results clearly indicates that the digital signal processing approach is able to give excellent results in this application, too. Index Terms--Charged particle identification, digital pulse shape processing, multidetector arrays technique, pulse shape analysis.

We have designed, built, and tested an on-line pre-analysis and data-storage unit for the data acquisition system of the 47r-detector CHIMERA. The unit uses special algorithms to perform particle identification and automatic peak detection. It tags in charge each event and stores the results on external unit, together with the raw data. It consists of two commercial 2 GHz workstations connected together through 1 Gb/s Ethernet boards and to the data acquisition system through a 100 Mb/s Ethernet. Index Terms--Data storage unit, multidetector online monitoring, online computational system.

Mass and atomic-number identification (ID) of reaction products is a fundamental requirement of any nuclear reaction study. An effective particle-ID method is demonstrated, based on pulse shape analysis/discrimination (PSD) applied to large-area, single-element silicon detectors. This technique uses commercial electronic modules and achieves atomic number resolution rivaling that typically obtained with multi-element ([DELTA]E-E) detector telescopes. The method is applied to the CHIMERA detector system without compromising its time-of-flight (TOF) resolution. In-beam tests of the PSD method have been performed with large-area, 300-[micro]m thick CHIMERA silicon detectors, measuring particles from the [sup.19]F + [sup.12]C reaction at Tandem energies. Performance of a simple PSD set up is discussed, for front and rear particle injection. Index Terms--Charge identification, planar silicon detector, pulse shape.

A 100 Msamples/s 14-bit sampling analog-to-digital converter has been used to perform digital pulse-shape acquisition of signals collected from CHIMERA telescopes. Two different kinds of tests have been carried out to check the performances. The signals from a typical CHIMERA detection cell have been collected using both a standard CHIMERA electronic chain up to the amplifier, and a very simple analog front end, basically reduced to the preamplifier. The obtained on-beam and on-line results are presented. Index Terms--Digital pulse shape acquisition, digital signal processing, multidetector arrays, particle identification, simple analog front end.

We investigated the merits of different event parameters in the identification of Light Charged Particles (LCPs) with CsI(Tl) scintillators read out by photodiodes at high incident energy (400 MeV/u). This investigation is made possible by digital signal processing the output signals. As in the conventional analogue case, the digitized signals allow the discrimination of light charged particles by computing the fast and slow components. In addition other identification parameters as the rise time of the output pulses of the CsI(Tl) come out nearly for free. Aim of this paper is the investigation of novel identification plots and the probe of their merits, in particular at relativistic energies. [ABSTRACT FROM PUBLISHER]

The dependence of the CsI(Tl) scintillation time constants and intensities on the particle ionization profile is at the basis of the Charge and Mass identification technique for Light Charged Products in Intermediate Energy Nuclear Physics multi-detector arrays. The possibility of storing the digitized waveforms in true beam experiments allows performing further offline analyses and makes available a data set related to the interaction of different particle types in a wide energy range. [ABSTRACT FROM AUTHOR]

The digital pulse shape data acquisition (DAQ) system used by the large area telescopes of the 4π-multidetector CHIMERA requires transferring large amount of data to the computer. This is necessary so that the same information can be extracted from the detector pulses as in previous analog based systems. To overcome this problem, we have used a sampling ADC-board equipped with two TigerSHARC digital signal processors. The board receives the data and reconstructs the event parameters online. The data volume is significantly. reduced by transmitting to the DAQ only the reconstructed event parameters. [ABSTRACT FROM AUTHOR]

Focuses on the introductory data acquisition system which was built to handle the signals from the detectors with a rate up to 1 kilohertz (kHz) on an estimation of 5000 electronic channels, referencing to the detector CHIMERA. Information on the CHIMERA detector; Reference to the on-line diagnostic system under development; Performance of the on-line data control.

An author index for the December 2013 issue of the journal "IEEE Transactions on Nuclear Science" is presented.

This index covers all technical items - papers, correspondence, reviews, etc. - that appeared in this periodical during the year, and items from previous years that were commented upon or corrected in this year. Departments and other items may also be covered if they have been judged to have archival value. The Author Index contains the primary entry for each item, listed under the first author's name. The primary entry includes the co-authors' names, the title of the paper or other item, and its location, specified by the publication abbreviation, year, month, and inclusive pagination. The Subject Index contains entries describing the item under all appropriate subject headings, plus the first author's name, the publication abbreviation, month, and year, and inclusive pages. Note that the item title is found only under the primary entry in the Author Index. [ABSTRACT FROM AUTHOR]

An author index for the December 2009 issue of "IEEE Transactions on Nuclear Science," Vol. 56 is presented.

The article presents the index to the vol. 52 issue of the journal "IEEE Transactions on Nuclear Science."