62137856
Org.Lcsim: Event Reconstruction in Java
Maximizing the physics performance of detectors being designed for the International Linear Collider, while remaining sensitive to cost constraints, requires a powerful, efficient, and flexible simulation, reconstruction and analysis environment to study the capabilities of a large number of different detector designs. The preparation of Letters Of Intent for the International Linear Collider involved the detailed study of dozens of detector options, layouts and readout technologies; the final physics benchmarking studies required the reconstruction and analysis of hundreds of millions of events. We describe the Java-based software toolkit (org.lcsim) which was used for full event reconstruction and analysis. The components are fully modular and are available for tasks from digitization of tracking detector signals through to cluster finding, pattern recognition, track-fitting, calorimeter clustering, individual particle reconstruction, jet-finding, and analysis. The detector is defined by the same xml input files used for the detector response simulation, ensuring the simulation and reconstruction geometries are always commensurate by construction. We discuss the architecture as well as the performance.
8455143
mesh2gdml: From CAD to Geant4
As particle detectors and physics analyses become more complex, the need for more detailed simulations of the detector response becomes increasingly important. Traditionally, two-dimensional engineering drawings have been interpreted by physicists who then implement approximations to the individual parts in software simulation packages. This process requires a high level of experience in both the abstraction of the physical volumes as well as the implementation in code, and is prone to error. mesh2gdml is a program which allows three-dimensional tesselated geometrical volumes to be converted into a format which the Geant4 simulation toolkit can import directly. This provides a pathway for simulating the response of detector elements which have been designed in CAD programs without having to write any code.
120038155
A measurement of the S- and P-wave content of antiproton annihilation at rest into two pions in liquid deuterium
Abstract Based on our measurement of the ratio f(π − π 0 p ) f(π + π − n ) =2.07±0.05 for antiproton annihilation at rest in liquid deuterium, we find that S-wave annihilation of the antiproton on the proton or neutron into ππ is dominant. We quote a 95% confidence level upper limit of 8% for P-wave annihilation into ππ.
120580004
Neutron emission from antiproton annihilation at rest in uranium
Abstract We have observed a large yield (5.77±0.16/ann.) of neutrons from antiproton annihilation at rest in a thin uranium target. Significant components of fission, evaporation and direct neutrons comprise this total. The large fission yield (2.50±0.10/ann.), as well as the high temperature (94±10 MeV) of the direct component, have not been anticipated in the intranuclear cascade model.
123115073
Intelligent detector design
As the complexity and resolution of imaging detectors increases, the need for detailed simulation of the experimental setup also becomes more important. Designing the detectors requires efficient tools to simulate the detector response and reconstruct the events. We have developed efficient and flexible tools for detailed physics and detector response simulation as well as event reconstruction and analysis. The primary goal has been to develop a software toolkit and computing infrastructure to allow physicists from universities and labs to quickly and easily conduct physics analyses and contribute to detector research and development. The application harnesses the full power of the Geant4 toolkit without requiring the end user to have any experience with either Geant4 or C++, thereby allowing the user to concentrate on the physics of the detector system.
37803086
3DPDF: Open Source Solutions for Incorporating 3D Information in PDF Files
Experimental science is replete with multidimensional information which is often poorly represented by the two dimensions of presentation slides and print media. Past efforts to disseminate such information to a wider audience have failed for a number of reasons, including a lack of standards which are easy to implement and have broad support. Adobe’s Portable Document Format (PDF) has in recent years become the de facto standard for secure, dependable electronic information exchange. It has done so by creating an open format, providing support for multiple platforms and being reliable and extensible. By providing support for the ECMA standard Universal 3D (U3D) and the ISO PRC file format in its free Adobe Reader software, Adobe has made it easy to distribute and interact with 3D content. Until recently, Adobe’s Acrobat software was also capable of incorporating 3D content into PDF files from a variety of 3D file formats, including proprietary CAD formats. However, this functionality is no longer available in Acrobat X, having been spun off to a separate company. Incorporating 3D content now requires the additional purchase of a separate plug-in. In this talk we present alternatives based on open source libraries which allow the programmatic creation of 3D content in PDF format. While not providing the same level of access to CAD files as the commercial software, it does provide physicists with an alternative path to incorporate 3D content into PDF files from such disparate applications as detector geometries from Geant4, 3D data sets, mathematical surfaces or tesselated volumes. I. MOVING BEYOND PRINT MEDIA PUBLICATION is undergoing a revolution due to the 21st Century multimedia explosion. In academia, education, and in the public in general, the trend is towards enhanced media. Digital publication of research journals, such as these IEEE Conference Proceedings, is becoming the standard. Rich internet applications such as animations, movies and interactive demonstrations are becoming the norm. Yet, despite the fact that PDF files are capable of supporting fully interactive 3D spatial and temporal content, the use of those features within the scientific community in general, and HEP in particular, has been almost non-existent. To-date, the utilization of 3D capabilities in PDF has been largely relegated to engineering applications incorporating CAD designs. The purpose of this presentation is to encourage wider use of these capabilities within the scientific community.
120065376
Improvements to MINOS CCQE Analysis
The MINOS experiment has the world's largest data set of neutrino interactions in the 1–10 GeV energy range. In addition, the data are neutrino interactions on iron, allowing us to explore the nuclear effects on neutrino scattering. We present two improvements to the MINOS charged current quasi‐elastic analysis presented at NuInt 2009 [1]: a background correction function extracted from two resonance enhanced selections, and an improved fit procedure that includes event samples selected by looking for the recoil proton.
117291086
Measurement of the charged kaon mass with the MIPP RICH
The currently accepted value of the charged kaon mass is 493.677 {+-} 0.013 MeV (26 ppm). It is a weighted average of six measurements, most of which use kaonic atom X-ray energy techniques. The two most recent and precise results dominate the average but differ by 122 ppm. Inconsistency in the data set needs to be resolved, preferably using independent techniques. One possibility uses the Cherenkov effect. A measurement of the charged kaon mass using this technique is presented. The data was taken with the Main Injector Particle Production experiment at Fermi National Accelerator Laboratory using a tagged beam of protons, kaons, and pions ranging in momentum from 37 GeV/c to 63 GeV/c. The measured value is 491.3 {+-} 1.7 MeV. This is within 1.4{sigma} of the current value. An improvement in precision by a factor of 35 would make this technique competitive for resolving the ambiguity in the X-ray data.