The Euroball Data Acquisition System

Paper: 318
Session: B (talk)
Speaker: Maron, Gaetano, INFN, Legnaro
Keywords: CORBA, data acquisition systems, event building, FCS, switches (eg ATM

The Euroball Data Acquisition System

G. Barazza (1), M. Bellato (1), L. Berti (1), P. Coleman-Smith (2),
A. Diaz (1), J. Ero (3), F. Fiumana (1), M. Gulmini (1), Z. Katona (4),
S. Letts (2), G. Maron (1), V. Pucknell (2), N. Toniolo (1), J. Zhang

(1) I.N.F.N. - Laboratori Nazionali di Legnaro, Italy}
(2) Council for the Central Laboratory of the Research Councils,
Daresbury Laboratory,UK}
(3) C.E.R.N. - Geneve, Switzerland
(4) K.F.K.I. - Budapest, Hungary

EUROBALL is a gamma ray spectrometer for nuclear physics experiments.
The estimated data rate coming from the front-end electronics will be
as high as 30 MByte/sec. Performance requirements
have required that the data flow be split in order to manage it with the
available technologies at affordable costs. Moreover, there is the need
for a scalable system which can be easily adapted to future requirements
simply adding new components or changing existing components.

The two-stage front-end electronics is composed of VXI-based digitizers
VME-based readout controllers coupled through a proprietary ECL bus and
purpose developed IP mezzanine card.
The back-end system is composed of a farm of UNIX workstations which
the raw data arriving from the front-end hardware. The connectivity
the front-end and back-end is provided by a Fibre-Channel switch which
acts as an event builder. Within the workstation farm a set of
services has been developed for the control, monitoring, histogramming
storage into tapes of the data. The implementation relies
on the Distributed Object Oriented approach (CORBA). A full Graphical
Interface (GUI) is provided based on TCL/TK.

The experiment will start to take data next January and the presentation
will report the firsts "on beam" results