William Trischuk


Contact Information
Full Curriculum Vitae
Static List of Publications

Brief CV

BSc., McGill (1986); PhD., Harvard (1990); CERN staff, (1990-96); Faculty, Toronto (1996-);  Visiting Scientist, Princeton (2001); KEK (2002), TRIUMF (2008-09);  CERN Visiting Professor (2013-2014); Director, Institute of Particle Physics (2004-2013);  APS Fellow (2010). 

Research Interests

Particle physics has gone through a period of more than three decades without an unexpected discovery. The two new phenomena found since 1976, the W and Z bosons (in the early 1980s) and more recently the top quark, were both predicted by theory based on precision measurements of other particle properties using the highly successful Standard Model of particle physics. Over the last 15 years I have concentrated on improving the precision with which parameters of the Standard Model are known. My thesis work resulted in a precise measurement of the W boson mass which yielded a prediction of the mass of the top quark. I followed that by studying the lifetime of the tau lepton. In both cases the application of a new particle detector technology to the measurement produced dramatic improvements in their precision.

My current research focuses on hadron collisions which give access to the highest energy collisions and hence have the potential for the discovery of new phenomena. These interactions also provide the highest production rate for many standard phenomena which leads to improvement of a variety of precision measurements as well. Currently I am a member of the ATLAS collaboration where diamond based solid-state particle detectors (see below) may be one of the keys to extracting new physics from experiments planned at CERN (Geneva, Switzerland) early in the next millennium. If diamond pixel detectors offer significantly enhanced radiation tolerance over those based on silicon substrates the University of Toronto will play a role in building, installing and operating such detectors in ATLAS. We are currently in the middle of a study of the radioactive activation that will occur when the ATLAS pixel detector begins operation in the harsh LHC collision environment. More information on the atlas inner tracker and pixel detector is also available. As a first application of diamond detectors in ATLAS we have recently installed a Beam Conditions Monitor system that has, at its heart, a series of ultra-radiation tolerant CVD diamond sensors. An overview of this proposal can be found here while more up-to-date information can be found here

Prior to joining ATLAS I was a member of the CDF collaboration for almost 20 years working at Fermilab, outside Chicago. I presented results on Rare B Decays at CDF at the 5th International Conference on Hyperons Beauty and Charm Hadrons held in Genoa in the summer of 1998. This included a description of our discovery of the Bc meson (a combination of a 'c' quark and an anti-'b'quark) I also summarised The experimental status of sin(2beta) and sin(2alpha) at the third international conference on CP violation in the B meson system at Taipei in Taiwan in December 1999. I remained a member of CDF until 2007 through initial data taking period of Run II at Fermilab. Several pieces of the CDF detector had been upgraded. A talk I gave at the KEK national accelerator in Japan in December, 2000 shows the status of the experiment as the silicon was just about to be installed. The CDF-Toronto group built precise support mechanics for the upgraded silicon vertex detector (SVX-II). A description of the successful repositioning of the CDF silicon track with the remotely position-able mount that we built in Toronto can be found in here. In the summer of 2003 I presented the results from the early Run II data-taking in CDF at the Canadian Association of Physicists Annual General Meeting in Prince Edward Island. I also gave a pair of summer school lectures on the state of B Physics measurements at CDF in the TRIUMF Summer Institute in August 2003 ( Lecture 1 , Lecture 2). Once data became available I worked with two of my graduate students and four other CDF collaborators to improve the W boson mass measurement. We have recently published the world's most precise measurement of the W boson mass which, coupled with predictions of the Standard Model indicates that the Higgs boson may be very light and, indeed, may be accessible at the Tevatron or in very early LHC running.

For the past fifteen years I have also been involved in a detector R&D program which is pushing the use of solid state micro-strip tracking detectors to experimental conditions of extremely high radiation typically found very near the interaction region in hadron collider experiments. To accomplish this we plan to replace the silicon semi-conductor substrate with chemically grown (CVD) diamond material. Because of its tightly bound lattice and high ionisation potential, diamond is more radiation tolerant than silicon. For more information on this you may want to visit the RD42 home page. We assembled and tested our first diamond pixel detector prototype in 1998 and have now published the results in NIM . I am now working on building a prototype full ATLAS pixel module with a CVD diamond sensor. More recently we have been adapting these diamond sensors to monitor beam losses in high intensity electron positron colliders. A description of this work can be found here . I was one of the founding spokespeople of this R&D project and, after a 12 year hiatus, where I remainded heavily invovled, I was re-relected co-spokesperson of the project in 2012.

I spent a year on sabbatical, during the 2001-02 academic year working on the Belle experiment at KEK in Japan. The experiment is dedicated to the study of very rare, CP-violating, effects in B meson decay. To do this we collect nearly 1 million B meson decays per day (0.5 fb^-1). To see how we are doing today have a look at here . I gave a summary of the CP violation results from Belle from the summer of 2002 at the SLAC Summer Institute. I also reported on work I did to measure sin(2 phi1) using J/Psi K_long decays at the Canadian Association of Physicists meeting in Quebec City. I have been helping to design a Xlinix based trigger processor for the Belle SVD-2.0 Readout. The trigger processor will compute the z impact parameter of tracks with a latency of 25 microseconds and reject beam-gas interactions, more efficiently. The SVD-2.0 was successfully installed in Belle in the early fall of 2002 and first data has been seen. The trigger processor is beginning to show preliminary results.


I am currently serving as associate chair for graduate studies.

Selected Publications

1. ``A Measurement of the W Boson Mass", F. Abe et al.,
Physical Review Letters 65, 2243 (1990). Journal E-print.
Physical Review D43, 2070 (1991). Journal E-print.

2. ``A Precise Measurement of the Tau Lepton Lifetime'', P. Abreu et al.,
Physics Letters B365, 448 (1995). CERN E-print.

3. ``First Measurements with a Diamond Microstrip Detector'', F. Borchelt et al.,
Nuclear Instruments and Methods A354, 318 (1995). CERN E-print.

4. ``The DELPHI Silicon Strip Microvertex Detector with Double Sided Readout'', V. Chabaud et al.,
Nuclear Instruments and Methods A368, 314 (1996). CERN E-print.

5. ``Measurement of b quark fragmentation fractions in the production of strange and light B mesons in pp-bar collisions at sqrt(s) = 1.8 TeV '', F. Abe et al., Physical Review D60, 092005 (1999). Journal E-print.

6. ``Rare B Decays from the CDF Experiment'', W. Trischuk,
published in the proceedings of the 5th International Conference on Hyperons Beauty and Charm Mesons, North Holland publishing. Journal E-print.

7.``Measurement of the differential dijet mass cross section in pp-bar collisions at sqrt(s) = 1.8 TeV'', T. Affolder et al.,
Physical Review D61, 091101(R), (2000). Journal E-print.

8. ``The First Bump Bonded Pixel Detectors on CVD Diamond'', W. Adam et al.,
Nuclear Instruments and Methods A436, 326 (1999). Journal E-print.

9. ``Measurement of J/Psi and Psi(2S) polarisation in pp-bar collisions at sqrt(s) = 1.8 TeV '', T. Affolder et al.,
Physical Review Letters 85, 2886 (2000). Journal E-print.

10. `` Measurement of CP-violating asymmetries in B0 -> p+p- decays '', K. Abe et al.,
Physical Review Letters 89, 071801, (2002). Journal E-print.

11. ``Indirect CP Violation Measurements from Belle'', W. Trischuk,
in the proceedings of the 2002 SLAC Summer Institute , available from my website here .

12. `` First Measurement of the W-Boson Mass in Run II of the Tevatron", F. Abe et al.,
Physical Review Letters 99, 151801 (2007). Journal E-print.
A more complete description has been been been published in Physical Review D, 77, 112001 (2008). Journal E-print.

13. ``The ATLAS Beam Conditions Monitor", V. Cindro et al.,
Journal of Instrumentation 3, P02004 (2008). Journal E-print.

14. ``Observation of a new partice in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC", G. Aad et al., Physics Letters B, V716, I1 (2012). Science Direct E-print.

Full Publication list from Spires

Selected Presentations

1. ``Status and Plans for the ATLAS Experiment'', Miami, December 2014. Slides .

2. ``The Higgs and Beyond'', Innaugural UofT Science Frontiers public talk, Toronto, December 2012. Video .

3. ``ATLAS Sees A Higgs Boson'', given at Queens University, November 2012. Slides .

4. ``Diamond Detectors: Present and Future Applications'', given at MIT, November 2011. Slides .

5. ``Highlights of Particle Physics in Canada'', given at 13th ISTC seminar, Novosibirsk, August 2010. Slides .

6. ``Mega Accelerators for Micro Science'', colloquium given at McGill University, Montreal, November 2009. Slides .

7. ``LHC Commissioning and the ATLAS Beam Conditions Monitor '', given at the ATLAS-Americas workshop, Vancouver, April 2008. Slides .

8. ``Measurements of the W Boson Mass and Width'', given at the Hadron Collider Physics Conference in Elba, Italy, May 2007. Slides .

9. ``Particle Physics in Canada: Present and Future'', given at the Perimeter Institute, February 2005. Slides .

10. ``Particle Physics at the Energy Frontier'', given at York University, November 2004. Slides .

11. ``Recent Advances in Diamond Particle Detectors'', given at IHCEP04, Bejing, August 2004. Slides .

12. ``The Status of the CDF-II Experiment'', given in the CAP meeting in Charlottetown, Prince Edward Island, June 2003. Slides .

13. ``Indirect CP Violation Measurements at Belle'', given at SLAC Summer Institute at Stanford in August 2002 Slides .

14. ``The CDF-II Silicon tracker & B Physics '', given at KEK Japan in December 2000. Slides .

15. ``Experimental Study of beta and alpha'', given at BCP3 in Tapei, Taiwan, December 1999. Slides .

Research Group

Miriam Diamond
Garrin McGoldrick
Chav Chhiv Chau
Dr. Nicola Venturi

Former Students and Postdocs


Matt Rudolph
Rachid Mazini
Kostas Kordas
Michael Riveline
Pierre Savard
Simon Gadomski
John Mayer


Dominique Tardif(PhD. 2011)
Ian Vollrath (PhD. 2006)
Bernd Stelzer (PhD. 2005)
Oliver Stelzer-Chilton (PhD. 2005)
Robert Cropp (PhD. 2000)
Bjoern Hinrichsen (PhD. 1999)
Dan Humphrey (MSc. 1999)

This site is maintained by William Trischuk.
Last updated August 2015.