Monte Carlo simulation (MCS) plays a key role in medical applications, especially for emission tomography and radiotherapy. However MCS is also associated with long calculation times that prevent its ...use in routine clinical practice. Recently, graphics processing units (GPU) became in many domains a low cost alternative for the acquisition of high computational power. The objective of this work was to develop an efficient framework for the implementation of MCS on GPU architectures. Geant4 was chosen as the MCS engine given the large variety of physics processes available for targeting different medical imaging and radiotherapy applications. In addition, Geant4 is the MCS engine behind GATE which is actually the most popular medical applications' simulation platform. We propose the definition of a global strategy and associated structures for such a GPU based simulation implementation. Different photon and electron physics effects are resolved on the fly directly on GPU without any approximations with respect to Geant4. Validations have shown equivalence in the underlying photon and electron physics processes between the Geant4 and the GPU codes with a speedup factor of 80-90. More clinically realistic simulations in emission and transmission imaging led to acceleration factors of 400-800 respectively compared to corresponding GATE simulations.
Charged product multiplicities and
Z distributions were measured for single multifragmenting sources produced in collisions between
129
Xe+
nat
Sn
and
155
Gd+
238
U
at the same available energy per ...nucleon.
Z distributions are found identical for both reactions while fragment multiplicities scale as the charge of the total systems. A complete dynamical simulation, in which multifragmentation originates in the spinodal decomposition of a finite piece of nuclear matter resulting from an incomplete fusion of projectile and target, well accounts for this experimental observation.
The CERN CMS tracker control system Drouhin, F.; Gross, L.; Vintache, D. ...
IEEE Symposium Conference Record Nuclear Science 2004,
2004, Letnik:
2
Conference Proceeding
Due to the high integration level of the experiments planned for the Large Hadron Collider (LHC) of the European Organization for Nuclear Research (CERN), the data acquisition and the control systems ...need complex developments both in hardware and software. The purpose of this paper is to describe the control system of a sub-detector of one of the CERN experiments, the tracker of the compact muon solenoid (CMS). The CMS tracker control system is based on dedicated hardware and software. The hardware is based on the front end controller (FEC), an interface board that hosts token rings for the communication with the control and communication unit (CCU) modules. These in turn contain dedicated I/O channels for the front end readout and control chips. The software is built in layers: one device driver, a C++ dedicated application program interface (API) plus a database for the storage of all the information needed for the front end electronics. This system will also be adopted in some other CMS sub-detectors.
The EPOS4 project is an attempt to construct a realistic model for describing
relativistic collisions of different systems, from proton-proton ($pp$) to
nucleus-nucleus ($AA$), at energies from ...several TeV per nucleon down to
several GeV. We argue that a parallel scattering formalism (as in EPOS4) is
relevant for primary scatterings in AA collisions above 4 GeV, whereas
sequential scattering (cascade) is appropriate below. We present briefly the
basic elements of EPOS4, and then investigate heavy ion collisions from 62.4
GeV down to 4 GeV, to understand how physics changes with energy, studying in
particular the disappearance of the fluid component at low energies.
Monte Carlo simulation (MCS) plays a key role in medical applications, especially for emission tomography (ET) and radiotherapy (RT). Unfortunately MCS is also associated with long calculation times ...that prevent for using it in routine clinical practice. Actually, a solution based on the use of computer clusters to solve the intensive computational issues is not realistic within routine clinical environment. Recently graphics processing units (GPU) became in many domains a cheap solution for the acquisition of a high power computation. The objective of this work was to develop an efficient framework for the implementation of MCS on GPU architectures. Geant4 was used as the MCS engine for targeting medical imaging and radiotherapy applications. We propose the definition of a global strategy and associated structures for such a GPU based simulation. The different steps needed for a Geant4 simulation were implemented on GPU. The first validations have shown equivalence in the underlying photon physics processes between the Geant4 and the GPU codes. Based on these simplistic simulations, we are expecting a speedup factor of over 200 for a complete simulation in emission tomography or in radiotherapy dosimetry.
The EPOS4 project is an attempt to construct a realistic model for describing relativistic collisions of different systems, from proton-proton (\(pp\)) to nucleus-nucleus (\(AA\)), at energies from ...several TeV per nucleon down to several GeV. We argue that a parallel scattering formalism (as in EPOS4) is relevant for primary scatterings in AA collisions above 4 GeV, whereas sequential scattering (cascade) is appropriate below. We present briefly the basic elements of EPOS4, and then investigate heavy ion collisions from 62.4 GeV down to 4 GeV, to understand how physics changes with energy, studying in particular the disappearance of the fluid component at low energies.
eConf C011127 (2001) WEDT005 The four LHC experiments at CERN have decided to use a commercial SCADA
(Supervisory Control And Data Acquisition) product for the supervision of their
DCS (Detector ...Control System). The selected SCADA, which is therefore used for
the CMS DCS, is PVSS II from the company ETM. This SCADA has its own database,
which is suitable for storing conventional controls data such as voltages,
temperatures and pressures. In addition, calibration data and FE (Front-End)
electronics configuration need to be stored. The amount of these data is too
large to be stored in the SCADA database 1. Therefore an external database
will be used for managing such data. However, this database should be
completely integrated into the SCADA framework, it should be accessible from
the SCADA and the SCADA features, e.g. alarming, logging should be benefited
from. For prototyping, Oracle 8i was selected as the external database manager.
The development of the control system for calibration constants and FE
electronics configuration has been done in close collaboration with the CMS
tracker group and JCOP (Joint COntrols Project)(1).
(1)The four LHC experiments and the CERN IT/CO group has merged their efforts
to build the experiments controls systems and set up the JCOP at the end of
December, 1997 for this purpose.
The four LHC experiments at CERN have decided to use a commercial SCADA (Supervisory Control And Data Acquisition) product for the supervision of their DCS (Detector Control System). The selected ...SCADA, which is therefore used for the CMS DCS, is PVSS II from the company ETM. This SCADA has its own database, which is suitable for storing conventional controls data such as voltages, temperatures and pressures. In addition, calibration data and FE (Front-End) electronics configuration need to be stored. The amount of these data is too large to be stored in the SCADA database 1. Therefore an external database will be used for managing such data. However, this database should be completely integrated into the SCADA framework, it should be accessible from the SCADA and the SCADA features, e.g. alarming, logging should be benefited from. For prototyping, Oracle 8i was selected as the external database manager. The development of the control system for calibration constants and FE electronics configuration has been done in close collaboration with the CMS tracker group and JCOP (Joint COntrols Project)(1). (1)The four LHC experiments and the CERN IT/CO group has merged their efforts to build the experiments controls systems and set up the JCOP at the end of December, 1997 for this purpose.
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