Robert E. Welsh

Chancellor Professor of Physics

College of William and Mary

A photo from our graduate brochure, should you "need" that
B.S., Georgetown University ,(cum laude) 1954
Active Duty, U.S. Air Force, 1955-1957

Ph.D., Pennsylvania State University 1960.

Academic/Research Positions:

1960-1963, Research Physicist, Instructor and Assistant Director of Nuclear Research Center, Carnegie Mellon University
1963-present, College of William and Mary Department of Physics; Associate Professor, 1963-68
1967-1972, Assistant Director, Space Radiation Effects Laboratory, Newport News, VA
Professor, 1968-present, Chancellor Professor, 1992-present (Chair, Department of Physics, 1988-1991)

Research Leaves:

July, 1972 - July, 1973 Rutherford High Energy Laboratory, Emgland
January, 1983 - August, 1984, CERN, Geneva, Switzerland
July, 1994 - July, 1995, Rutherford Laboratory and Oxford University, England

Research Interests:

Particle Physics

My research has been principally in experimental particle physics. Our studies have involved muons, pions, kaons, sigma hyperons and antiprotons. The research group at William and Mary has included faculty members Mort Eckhause and John Kane (and, earlier, Rolf Winter and Robert Siegel) plus postdocs and graduate and undergraduate students. Experiments carried out by our group since 1980 include:

Measurement of the lifetime of the positive muon at TRIUMF
Two muonic atoms experiments at SIN/PSI in Villigen, Switzerland; (Search for metastable 2S muonic He, Diffusion of muonic p and d atoms.)
At CERN a measurement of the x-rays from antiproton-proton atoms and antiproton-deuteron atoms in collaboration with British and Dutch physicists.
And, At Brookhaven:
Search for the Standard-Model violating decay of a neutral kaon into a muon plus an electron (E791 and E871)
First observation of the decay of the neutral kaon into two electrons
Searches for the H Dibaryon
Precision measurement of the decay of the neutral kaon into two muons
Search for a light gluino
Measurement of the magnetic moment of the negative sigma hyperon
Measurement of the strong interaction of kaons, antiprotons and sigma hyperons with the nucleus; at Brookhaven National Laboratory
We have helped design and install the calibration laser systems on the Time of Flight counters for the CLAS detector in Hall B at Jefferson Laboratory.

Small Animal Imaging

Beginning in 1999, I joined with biologists from William and Mary (Profs. Margaret Saha and Eric Bradley) and members of Jefferson Lab's detector group (Stan Majewski, Mark Smith, Drew Weisenberger, Randy Wojcik and Brian Kross) in work on nuclear techniques in small-animal imaging. This effort is based on the development of segmented scintillators coupled to position-sensitive photomultiplier tubes. Such devices can be used to follow the uptake of tagged radioistopes in living systems. The availability from commercial sources of hundreds of ligands tagged with Iodine-125 has given the possibility of new types of in vivo studies of the metabolism of biologically interesting substances. The relatively long-lived I-125 emits soft photons (~30 keV) especially suitable in small animals such as mice. This approach allows such studies at labs where positron emitters or other short-lived isotopes are not available. Several talks have recently been given based on this work over the past several years. Most are shown in the list below.

Cipher and Code Devices

As a hobby I collect cipher and code devices. A short paper is in preparation(in collaboration with a Canadian friend more skilled in this field than I) based on a small, Swiss strip-cipher device which he owns and a similar French device which I own. 20th c.Strip Sphinx Cipher Device from France If you know the age or other facts about it, please email me. I am always pleased to see pictures of old cipher devices or to hear of such devices that may become available and need a new home.
(Please see below for additional pictures and links to cipher devices)

Research Students:

Ph. D. graduates in the past ten years: Rob Martin and Chris Hoff, received the Ph. D. in 1998. In 1999 Kevin Hern, working with our group under Mort Eckhause, received the Ph. D. Andrew Norman, working under John Kane, received the Ph. D. in early 2004. All four of these recent students based their Ph. D. thesis on work with our group in rare decay searches at Brookhaven Lab.
Robert Saunders - carried out his undergraduate senior honors thesis work in small animal imaging.He was graduated with high honors in Spring, 2000. He presented the results of this work at the Chapel Hill meeting of the American Physical Society. He is studying for the Ph. D. in medical imaging at Duke.
Amoreena Ranck carried out honors research (in medical imaging)throughout the 2000-2001 academic year. She is presently in medical school at U. Va.
John Feldmann, Luke Ng and Kevin Knott did their senior thesis research with us throughout 2000-2001 as well. Kevin received the harrison Prize for undergraduate research, was elected to Phi Beta Kappa and is now playing professional soccer. Each of these students presented a paper at a meeting of the APS on their research.
In Summer, 2001, Mr. Jianguo Qian, a graduate student in Applied Science, and two physics undergraduates, Mr. Paul Brewer and Mr. Kevin Smith, joined this project. In fall 2001, Sam Dunn began his undergraduate thesis research with us (Graduated May 2002) while Kevin Smith completed his BS in May 2003 after doing research with our group. Kevin is now in graduate school at William and mary in the physics department. Ms. Julie Cella joined this effort in 2003 and graduated in May 2004. She spent the following year working with "Teach for America" teaching at a minority high school in New mexico. In Fall, 2004, Mr. William Hammond and Ms Annie Guzzi joined us. Mr. Hammond received his B.S. in May, 2005 and his thesis topic was based on the use of KI blocking of the mouse thyroid to reduce uptake of radioactive iodine. Ms. Guzzi worked on fluorescent/luminescent imaging using a cooled-ccd camera to image quantum dots with a goal of employing the technique in imaging of rodents. Mr Christopher Brittin also joined our group and developed a reliable electronic monitor for mice. Mr. Brittin has also worked on dual-energy imaging in x-ray techniques with small animals.


Publications, Reviews, Abstracts etc. (Since 1995)

Measurement of the Branching Ratio for the Rare Decay K0L-> mu mu
A. P. Heinson, et al.
Phys. Rev. D51, 985 (1995)

Search for the Presence of H Particles in a Neutral Beam
J. Belz, et al.
Nuc. Phys. A585, 97c (1995)

Nuclear Capture in the Atomic Cascade of Kaonic, Antiprotonic and Sigma Hyperonic Exotic Atoms
C. J. Batty and R. E. Welsh
Nuclear Physics A589, 601 (1995)

Search for Diffractive Dissociation of a Long-lived H Dibaryon
J. Belz, et al.
Phys. Rev. D53, 3487 (1996)

Search for the Weak Decay of an H Dibaryon
J. Belz, et al.
Phys. Rev. Lett. 76, 3277 (1996)

Diffusion of Muonic Deuterium and Hydrogen Atoms
D. J. Abbott, et al.
Phys. Rev. A55, 214 (1997)

Search for the Weak Decay of an H Dibaryon (Addendum)
J. Belz, et al.
Phys. Rev. C56 (1997)

First Observation of the Rare Decay K0L -> ee
D. Ambrose, et al.
Phys. Rev. Lett. 81, 4309 (1998)

New Limit on Muon and Electron Lepton Number Violation from the Decay K0L -> mu e
D. Ambrose, et al.
Phys. Rev. Lett. 81, 5734, (1998)

Thomas Edison, Life, Love and Lightbulbs
Book Review of "Edison, A Life of Invention", by Paul Israel
Physics World, p44, December 1998

A Compact Beam Stop for a Rare Kaon Decay Experiment
J. Belz, et al.
Nuc. Inst. and Meth. in Phys. Res. A428, 239 (1999)

The Time-of-Flight System for the CEBAF Large Acceptance Spectrometer
E. S. Smith, et al.
Nucl. Inst. and Meth. in Phys. Res. A432, 265-298 (1999)

Preliminary Results of the In Vivo Imaging of the Uptake of [I-125]RTI-55 in the Mouse Using an Optimized Small Animal Gamma Camera
A. Weisenberger, B. Kross, S. Majewski, R. Wojcic, E. Bradley, M. Saha, B. Stetka, R. Saunders and R. E. Welsh
Poster presented at High Resolution Imaging Conference, Amsterdam, September, 1999

A Gamma Ray Imaging Device for Small-Animal Studies
Robert Saunders, et al. Paper LD.06. Presented at American Physical Society Meeting, November 1999, (Chapel Hill)

Dual-Modality Small Animal Imaging System
Amoreena Ranck, et al.
American Physical Society Division of Nuclear Physics, October 2000

Single-Photon Computed Tomography with Large Position-Sensitive Phototubes
John Feldmann, et al.
American Physical Society Division of Nuclear Physics, October, 2000

Improved Branching Ratio Measurement for the decay K0L-> mu+ mu-
D. Ambrose, et al.
Phys. Rev. Lett 84, 1389, (2000)

Novel Technique for Coregistration of Biological Images in a Multimodality Detector Array
Amoreena Ranck, et al.
American Physical Society, Southeast section, November, 2000
Bradley, E.L, Gleason, K. K. , Majewski, S., Ranck, A. E., Saha, M. S. Smith, M. F. Weisenberger, A. G., Welsh, R. E. and Wojcik, R. "In Vivo Imaging of the Distribution and Pharmacodynamics of Iodine-125 Labeled Insulin During the Development of Streptozotocin-Induced Hyperglycemia in the C57BL/6J Mouse with a Dedicated Gamma Imager", High Resolution Imaging Conference, Rockville MD, Sept 2001

Weisemberger, A. G. et al. (same conference and authors as preceding paper, "Development of a Miniature SPECT-CT System for Small Animnal Imaging"

Ng, Luke, Robert E. Welsh, Eric L. Bradley, Margaret Saha, Brian Kross, Stan Majewski, Vladimir Popov, Mark F. Smith, Andrew G. Weisenberger and Randolph Wojcik, "Experimental Results and Predictive calaulations for Pinhole Collimators Used in Small Animal Nuclear Imaging", American Physical Society-Annual Meeting, Washington, DC, April, 2001."

Welsh, R.E.,Bradley, E. L., Kross, B., Majewski, S., Popov, V., Qian, J. Ranck, E. L., Saha, M. S., Smith, K., Smith, M. F., Weisenberger, A. G., and Wojcik, R. , "An Economical Dual-Modality Small Animal Imaging System With Application to Studies of Diabetes", IEEE Nuclear Science Symposium, San Diego, CA, November, 2001.

Book Review of: "The Wonders of Physics"
Lev Aslamazov and Andrei Varlamov, 2001, World Scientific
Physics World, November 2001

Weisenberger, A. G., Wojcik, R., Bradley, E. L., Brewer, P., Majewski, S., Qian, J., Ranck, A. E., Saha, M. S., Smith, K., Smith, M. F., and Welsh, R. E.,"SPECT-CT System for Small Animal Imaging", IEEE Nuclear Science Symposium and Medical Imaging Conference, San Diego, CA, Nov. 2001,

Saha, M. S., Bradley, E. L. , Brewer, P., Gleason, K. K. , Kross, B. , Majewski, S., Popov, V., Qian, J., Ranck, A., Smith, K., Smith, M. F., Weisenberger, A. G., Wojcik, R., Welsh, R. E., "Incorporation of a Fluoroscopic X-Ray Modality in a Small Animal Imaging System,", IEEE Trans. Nucl. Sci., pp. 333-338, vol. 50, no. 3, June 2003.

Weisenberger AG, Wojcik R, Bradley EL, Brewer P, Majewski S, Qian J, Ranck A, Saha MS, Smith K, Smith MF, Welsh RE, "SPECT-CT System for Small Animal Imaging," IEEE Trans. Nucl. Sci. pp. 74-79, vol 50, no. 1, February, 2003.

Robert E. Welsh, Eric L. Bradley, Julie Cella, Brian Kross, Stan Majewski, Vladimir Popov, Jianguo Qian, Margaret S. Saha, Kevin Smith, Mark F. Smith, Andrew G. Weisenberger and Randolph Wojcik, "Simultaneous 125I SPECT Imaging of Small Animals with Pinhole and Parallel Collimation"; Paper M7-42, presented (by J. Qian) at IEEE Medical Imaging Conference, October, 2003, Portland, OR.

"Comparison of CsI(Tl) and NaI(Tl) Pixel Scintillators" K. J. Smith, E. L. Bradley, J. T. Cella, M. S. Saha and R. E. Welsh Talk HB.006, American Physical Society, Wilmington, NC, November 2003.

J. T. Cella, E. L. Bradley, M. S. Saha, K. J. Smith and R. E. Welsh "Use of Optical Coupling and Glass Spacers in Position Sensitive Scintillation Detectors" Talk HB.003 American Physical Society, Wilmington, NC, November 2003.

Practical Aspects of 125I SPECT Imaging: Mouse Bed and Bed Support E. L. Bradley, M. S. Saha, R. E Welsh, A. G. Weisenberger and R. Wojcik; Abstracts of Accepted Submissions to HiRes Conference, Madrid, Spain, September 2003.

J. T. Cella, Small Animal Nuclear Imaging. Undergraduate Research Symposium, September 2003. Williamsburg, VA.

A "Mouse-Sized" Gamma Camera for Biological Imaging, Eric L. Bradley, Julie Cella, Stan Majewski, Vladimir Popov, Jianguo Qian, Margaret S. Saha, Mark F. Smith, Andrew G. Weisenberger, and Robert E. Welsh. Conference record, Rome Meeting of IEEE Medical Imaging Conference, October, 2004.

Nuclear imaging of iodine uptake in mouse tissues, W.T. Hammond, J.T. Cella, C. McLoughlin, K.J. Smith, R.E. Welsh, E.L. Bradley, M.S. Saha, J. Qian, S. Majewski, V. Popov M.F. Smith and A.G. Weisenberger

Recent Colloquia and Seminars Presented

The talks I have given in the past few years have been based on my avocation, codes and ciphers, and have included demonstrations using my Enigma Machine (German Army type; Serial Number A 10360) and Swiss NEMA cryptographic machine the 1943/44 Swiss electromechanical cipher device. Also included is theU.S. Army M209B Converter cryptographic device (mine made by Smith-Corona Typerwiter Company in the 1940's)

Our recent presentations on Small Animal Imaging are listed in the previous section.

"The Enigma Machine"
Jefferson Lab Colloquium
6 May 1998

"Codes and Ciphers, The German Enigma Machine"
Physics Colloquium, Old Dominion University
October, 1998

"The Enigma Machine"
Homecoming Academic Festival, William and Mary
October, 1998

"Electromechanical Cipher Devices"
Colloquium, Computer Science Department, College of William and Mary
November, 1998

"How the Polish and Bletchley Park Mathematicians broke the Enigma"
Homecoming Academic Festival, William and Mary
October, 1999
and: Jefferson Lab Graduate Student Seminar
Summer, 2000

"The Real Story Behind the Movie U571/ How the German Four-Rotor Naval Enigma was Broken"
Homecoming Academic Festival, College of William and Mary
October, 2000

"Electromechanical Cipher Devices"
Homecoming Academic Festival, William and Mary, October 2001.

"The Enigma Machine and Other Mechanical Cipher Devices"
The Mariners Museum, Newport News, VA, 27 Feb. 2003

"Breaking the Enigma Cipher in WWII",
Christopher Wren Town and Gown, Williamsburg, VA, 13 March 2003.

"Was a Misalligned Rotor in a German Enigma Cipher Machine the Origin of the Naval Four-Rotor Enigma?"
XXII Scientific Instrument Symposium, Newport News, VA, September, 2003

Contact points:

Office (W&M):   (757) 221-3505  (Tuesdays, Thursdays, Afternoons of Fridays)
Jefferson Lab: Head, Student Affairs office and Coordinator of Virginia Physics 
Consortium (757) 269-7583        
FAX:            (757) 221-3540
E-Mail:   or
Snail-Mail:   Dept. of Physics
              College of William and Mary
              Williamsburg, Virginia
              23187    USA

Some Enigma Links of Interest, many with links to others.

Download Your Own Enigma Machine
Frode Weierud's crypto pages and links
Bill Momson's articles from Nautical Brass Magazine
With special reference to the three Polish codebreakers who first broke Enigma
Univ. of Arizona math course of interest
Richard Brisson's "Vintage Cryptographic Equipment" page
David Hamer's list of links to crypto sites
David Hamer's home page

Please email any comments or questions...
last updated 9 May 2005

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