Dr. Fortner Research

Research Interests:
High-speed and real-time electronics for particle identification and data acquisition, trigger algorithms for sampling large data sets.

Experimental particle physics involves the construction and operation of large detectors. The detector acts as a microscope, probing the interactions of particles from high-energy accelerators at the smallest measurable distances. These detectors must be sensitive to the unique properties of long-lived particles such as the electron, muon, photon, neutrino, proton, neutron, and pion. From measurements of the individual particles or related groups of particles we can deduce the short-lived particles created in the original collision. A typical detector today may have over a million independent measuring devices synchronized to detect particle interactions at rates well in excess of a megahertz. To handle the data and select interactions of scientific interest, a multi-stage set of electronics and software known as the trigger samples a fraction of the data and makes a decision to acquire and pass on the data for further analysis.

My research presently involves work with the D0 detector at the Fermi National Accelerator Laboratory, which is located less than one hour from NIU. I have been involved with the D0 muon subdetector system since 1987, when I began installing and testing the original detector and electronics. In 1997 I developed the design of a new second stage trigger (of three) to identify the tracks from muons emerging from particle interactions. This muon trigger samples about 5 kilobytes of data at a rate of 10 kilohertz and makes a decision in less than 100 microseconds. I can usually be found as the shift captain, overseeing the real-time operation and data acquisition of D0.

Experimental particle physics continues to develop more powerful accelerators and detectors to measure their interactions. One such new apparatus is the ATLAS detector at CERN near Geneva, Switzerland. ATLAS will be faced with data rates and trigger sampling an order of magnitude greater than the current generation of machines. High speed buffers and switches make it possible to design a trigger that will permit efficient identification of interesting events that probe interactions at ever smaller distances.

Selected Publications on D0 and its muon system:
  • "The Upgraded D0 Detector," The D0 Collaboration (V. Abazov, et al.), Nucl. Inst. and Meth., A565, 463 (2006).
  • "The Muon System of the Run II D0 Detector," V.M. Abazov, et al., Nucl. Inst. and Meth., A552, 372 (2005).
  • "The Level-2 Muon Trigger at D0," M. Fortner, A. Maciel, H. Evans, B. Kothari, S. Uzunian, IEEE Trans. Nucl. Sci, 49, 1589 (2002).
  • "The D0 Trigger," M. Fortner, Computing in High Energy Physics Conference, 1998, Chicago, Illinois.
  • "A Massively Parallel Processor for Level 2 Muon Triggers at D0," M. Fortner, T. Lagger, and R. Markeloff, Nucl. Inst. and Meth., A389, 59 (1997).
  • "Analog Neural Networks in an Upgraded Muon Trigger for the D0 Detector," M. Fortner, New Computing Techniques in Physics Research 11, 381 (1992).
  • "The VME-Based D0 Muon Data Acquisition System," M. Fortner, et al., IEEE Trans. Nucl. Sci., 38:2, 490 (1991).