Speaker
Pietro Ottanelli
(FI)
Description
In the last few decades, Pulse Shape Analysis techniques (PSA) has proven
to be a very powerful tool to identify nuclear fragments that are stopped
inside the active layer of a single detector. These techniques, as the name
suggests, are based on the extraction of informations from the shape of the
signal produced by the impinging fragment.
The NUCL_EX group of INFN has focused its recent work towards the
development of highly performing detectors for studying nuclear collisions
at energies around or below the Fermi Energy. In this field the capability
to detect and identify nuclear fragments (both in Z and A) plays a crucial
role, hence the group made great efforts in obtaining very good isotopic
resolution. As of today, the FAZIA array, composed of several three-stage
telescopes (Silicon-Silicon-Cesium) is the result of these efforts,
granting the possibility to identify in mass the fragments up to Z=20 and
even more, using both DeltaE-E techniques and PSA.
During the FAZIA R&D two main PSA techniques for Silicon detectors were considered,
one techniques uses the correlation of the charge-signal rise time with the
energy (amplitude) and the other uses the correlation of the current signal
maximum value with the energy. Since the latter has shown better performances,
the FAZIA apparatus has been designed in order to acquire also the
current signal coming from the silicon detector, thus achieving better results concerning isotopic resolution.
However, the slightly older GARFIELD+RCo detector, which is also managed by
the NUCL_EX group, does not have the possibility to acquire the current
signal and uses the rise-time PSA to identify fragments.
To overcome this limit, hoping for better performances, we have implemented
on the new FEE electronics of the apparatus a real-time algorithm that
performs real-time Cubic Spline interpolation of the charge signal and then
differentiates the interpolated signal to obtain
the current signal, thus allowing for the current PSA to be exploited.
The algorithm has been tested in December 2015 at LNS during a campaign of
the FAZIA apparatus and recently al LNL during the commissioning of the new
electronic with the GARFIELD+RCo apparatus, showing encouraging results.
Selected session
Accelerators and Instrumentation
Primary authors
Co-authors
Antonio Maria Buccola
(F)
Daniela Fabris
(PD)
Fabiana Gramegna
(LNL)
Giorgia Mantovani
(LNL)
Magda Cicerchia
(LNL)
Marco Cinausero
(LNL)
Tommaso Marchi
(INFN - LNL)
