Detectors Based on Straw Tubes in Vacuum
Methodical Development and Experimental Study in Order to Construct High Resolution Detector Based on Straw Tubes Working in Vacuum
Tech Area / Field
- INS-DET/Detection Devices/Instrumentation
- INF-SOF/Software/Information and Communications
- PHY-PFA/Particles, Fields and Accelerator Physics/Physics
3 Approved without Funding
Georgian Academy of Sciences / A. Razmadze Mathematical Institute, Georgia, Tbilisi
- Joint Institute of Nuclear Research, Russia, Moscow reg., Dubna
- University of California / Department of Physics and Astronomy, USA, CA, Irvine\nCERN, Switzerland, Geneva
Project summaryThe proposed project deals with theoretical and experimental studies for development of technology for design and construction of high resolution detector based on straw tubes working in vacuum. The detector prototype module and its corresponding front-end readout electronics to be developed and constructed within the project employ new technologies that have never been used in large scale collider experiments.
The prototype of the module of high resolution detector based on straw tubes working in vacuum, constructed within the framework of the project, is intended for international experiment NA48/3 (project P326) on SPS (Super Proton Synchrotron) CERN, as an integral part of the particle identification and trigger system. Within the project P326 (NA48/3) on high intensity beam of Kaons SPS CERN, been under preparation by 8 countries with participation the USA, Germany, France, Italy, etc., and also two international organizations - CERN and JINR, approved by physical community and supported by scientific committees and directorate of CERN, it is proposed a task of conducting the convincing check of Standard Model of structure of the matter on the basis of measurement with 10 % accuracy of the parameter Vtd of matrix Cabibbo-Kobayashi-Maskawa. The experiment proposed is aimed at the extraction in 2 years of the set of data of 80 decay events K+ →π+νν, the relative probability of which composes ~10-10, with the ratio of signal to background 10:1.
The procedure of experiment assumes multiple determinations of parameters of the decayed and created charged particles for the exception of background processes, which defines the minimal requirements to structure of the tracker detector: it must consist at least of 2 spectrometers, in each of them the particle to be restored with the high pulse resolution. This condition can be satisfied with the two-arm magnetic spectrometer incorporating 6 coordinate detectors, capable to determine X, Y, U and V coordinates of a track in each.
For conducting of such experiment corresponding experimental module (NA48/3) should include coordinate detectors with the characteristic geometrical sizes about 2500 mm, having high (~100 micron) spatial resolution at absence of the matter in the region of the beam of primary kaons and with the minimum of substance in the area of decay of kaons and registration of secondary particles. Last condition assumes placing of such detectors in the vacuum chamber with vacuum about 5.10-6 Торр, adjacent to decay volume.
To meet most completely the claims listed above for coordinate detectors, it seems the most perspective their design on the basis of thin-walled (straw) drift tubes. The optimum diameter of such tubes (10 mm) is dictated by the considerations of their reliable work at loadings assumed in experiment at the minimal cost. A total quantity of straw- tubes in a spectrometer will be at a level of 12000 pieces. As estimations show, at good compliance of calculated geometrical parameters and configuration of actually constructed chambers and the use of fast electronics in combination with a "slow" gas mixture, it is possible to obtain the spatial coordinate resolution of detectors of about 80 micron.
At present straw detectors successfully compete with such traditional detectors, as multi-stranded proportional and drift chambers. This is explained, mainly by the fact that the radiation thickness of these detectors is less, and the cylindrical geometry for each channel of registration provides optimum temporal collection of the electrons of ionization drifting to the anodes. Moreover, the simple design of chambers allows to unify them and to widely use industrial opportunities for manufacturing a lot of elements of detectors. Being the detectors with the minimum quantity of substance, the straw-chambers are most preferable as the trackers for many physical tasks. It should be noted, that in installations for LHC thereto, it is now planned practically the use of only silicon and straw-detectors. The latter provide wit combining opportunities of the coordinate detector and the identifier of particles. From the current works on creation of straw detectors in JINR, it should be noted the participation in projects ATLAS and COMPASS in CERN.
The development and design of detector prototype will proceed based on simulation results. At present the research works for obtaining of optimum parameters of the detector are carried out at JINR and the 48-channel prototype of the detector with straw-tubes in length more than 2 meters is created, the characteristics of which is planned to test during testing in the cosmic rays at JINR and in a beam of pions SPS CERN as component of NA48/2 installation..
The international community of linear collider developers can use the results of these tests to fine tune their detector designs. The data collected within the beam tests will be analyzed to advance the development of algorithms and linear collider detectors. The data collected with the prototype detectors will be of great importance in tuning existing Monte Carlo simulation software. The data will be archived for future use in the simulation of particle detectors.
The novel technologies developed through the project will provide a basis for further use in commercial applications, such as in health care and national security (detection techniques for medical and other usages, including surveillance for national security).
The foundation for project is formed by:
- Highly-developed technologies of fabricating various detectors at JINR, meeting the peculiar needs of high energy physics fundamental experiments, and facilities for their production.
- Highly-developed advanced computing technologies for numerical experiments and simulation of various physical phenomena at Theoretical Physics Division of MI.
There are existing qualified research teams at JINR and Theoretical Physics Division of MI and JINR, currently focused on the various segments of the project, existing skills and “know-how”, technology and equipment and developed infrastructure. So, already now in a mode of repetition work at LPP JINR function the shop for "reinforcement" of straw and the shop for their preparation for the subsequent installation in the detector. The collaborators of the project do have interest in the scientific results of the project for research goals. Also, there are prerequisites that they have commercial interests too and will participate in the marketing of the project results.
Project implementation will enable:
- To accumulate experimental, theoretical and numerical data for demonstrating the technology facilities for the production of the high resolution detector based on straw tubes working in vacuum;
- To develop novel software for numerical simulation of facilities of the high resolution detector based on straw tubes working in vacuum;
- To develop, found and test original technology of design and construction of the high resolution detector based on straw tubes working in vacuum.
- to construct prototype of the high resolution detector based on straw tubes working in vacuum for international experiment NA48/3 (project P326) on SPS CERN.