Jeff Wilkerson
email:
wilkerje@luther.edu 
phone: 563-387-1226
fax: 563-387-1080

Professor Wilkerson joined the Luther College physics department in the Fall of 1997. He received his B.S. in Physics from Indiana University, and has his Ph.D. in physics from the University of California, Berkeley.

Courses Taught: Astrophysics -- General Astronomy --Classical Physics II -- Thermodynamics and Statistical Mechanics --

Great Ideas in Natural Science --Physical Science -- Modernity: Natural Sciences

No Courses 2013-14

Follow me on Twitter

Research Interests: Currently I have two primary areas of research interest. 

 (1) Study of the use of gaseous xenon as a detector medium for hard x-rays.  Hard x-ray detectors are used to study black holes, neutron stars and active galactic nuclei.  In xenon gas the energy of an incident x-ray gets converted to scintillation light, the strength of which is proportional to the energy of the x-ray absorbed.  In the laboratory we have been studying this process.  More details on this project.

 (2) Development of rapid photometric techniques for the study of stellar signal variations.  We acquire hundreds or thousands of images of a rich star field in a given night.  We then perform a statistical analysis of the signal (= apparent brightness) of each star in the field over the course of the night. While this work should prove useful for the study of everything from meteors to near-earth asteroids to variable stars, we are primarily interested in searching for foreground objects that pass between us and a distant star, leading to a sudden and brief decrease or increase in the flux measured from the background star.  More details on this project.

RESEARCH WITH UNDERGRADUATES

“Assessment of phase-dependent scatter in the light curves of long period variable stars” with Clara Olson, Luther College, 2012.

“Eclipsing binary timing studies” with Jennifer Schulz, Luther College, 2012.

“Heterogeneity in the population of newly discovered pulsating stars in the field of open cluster M23” with Donald Lee-Brown, Luther College, 2011-13. Results presented at the Midstates Consortium for Math and Science Undergraduate Research Symposium, Chicago, IL, November 2011, Mid-American Regional Astrophysics Conference ,Lawrence, KS, April 2012, Midstates Consortium for Math and Science Undergraduate Research Symposium, St. Louis, MO, November 2012 and Iowa Academy of Science Annual Meeting, Indianola, IA, April 2013.

“A Fourier-based search for microvariability in the long-period variables in the field of open cluster M23” with Andrew Becklin, Luther College, 2011-12.

“A statistical test for stellar variability on long timescales” with Donald Lee-Brown, Luther College, 2010. Results presented at the Mid-American Regional Astrophysics Conference, Kansas City, MO, April 2011.

“Building a user interface for public science with seven years of astronomical data from Luther College” with Kirsten Strandjord, Luther College, 2010. Results presented at the Mid-American Regional Astrophysics Conference, Kansas City, MO, April 2011.

“Monitoring the long-term luminosity stability of stars in the field of Open Cluster M23 ” with Alex Sperry, Luther College, 2009-10.

“Statistical studies of potential small stellar flare events in stars in the field of Open Cluster M23” with Kirsten Strandjord, Luther College, 2009.

“Study of period evolution of eclipsing binary stars in the field of Open Cluster M23 ” with Drew Doescher, Luther College, 2009.

“Simulating the detection of stellar flares” with Kirsten Strandjord, Luther College, 2008. Results presented at the Mid-American Regional Astrophysics Conference, Kansas City, MO, April 2009.

“Searching for flare stars in the field of Open Cluster M23 ” with Drew Doescher, Luther College, 2008.

“Stellar variability in the field of Open Cluster NGC7380 ” with Ujjwal Joshi, Luther College, 2007.

“Variable stars in the field of open cluster NGC2286 ” with Andrea Schiefelbein, Luther College, 2007-2008. Results presented at the Mid-American Regional Astrophysics Conference, Kansas City, MO, April 2009.

“BVRI color measurements of stars in the field of open cluster M23 ” with Andrea Schiefelbein and Nathan Rengstorf, Luther College, 2006-2007. Results presented at the Mid-American Regional Astrophysics Conference, Kansas City, MO, April 2007.

“Search for period evolution in short-period eclipsing binaries in the field of open cluster M23 ” with Ujjwal Joshi, Luther College, 2006-2007. Results presented at the Midstates Consortium for Math and Science Undergraduate Research Symposium, Washington University, November 2006 and at the Mid-American Regional Astrophysics Conference, Kansas City, MO, April 2007.

“Monitoring variable stars in the field of open cluster M23 ” with Andrea Schiefelbein, Luther College, 2006. Results presented at the Midstates Consortium for Math and Science Undergraduate Research Symposium, November 2006 and further results presented at the 210th meeting of the American Astronomical Society, Honolulu, HI, May 2007

“Survey of rotating variable stars in the young open cluster NGC7380 ” with Nathan Rengstorf, Luther College, 2006-2007. Results presented at the Midstates Consortium for Math and Science Undergraduate Research Symposium, Washington University, November 2006 and at the Mid-American Regional Astrophysics Conference, Kansas City, MO, April 2007.

“Developing a technique to survey variable stars in open clusters ” with Todd Brown and Brajesh Lacoul, Luther College, 2005.

“Using rapid photometry to search for Kuiper Belt Objects ” with Todd Brown, Luther College, 2004-2005.and Results presented at the Midstates Consortium for Math and Science Undergraduate Research Symposium, Washington University, November 2004 and at the 206th meeting of the American Astronomical Society, Minneapolis, MN, May 2005

“Detecting novel, chaotic variability in open cluster stars ” with Kari Frank, Luther College, 2004-2005. Results presented at the Midstates Consortium for Math and Science Undergraduate Research Symposium, Washington University, November 2004, at the R.J. McElroy Faculty/Student Research Symposium, Wartburg College, May 2005 and at the 206th meeting of the American Astronomical Society, Minneapolis, MN, May 2005.

“Searching for planets in open star clusters ” with Brajesh Lacoul and Alex Nugent, Luther College, 2004-2005. Results presented at the Midstates Consortium for Math and Science Undergraduate Research Symposium, Washington University, November 2004 and at the 206th meeting of the American Astronomical Society, Minneapolis, MN, May 2005.

"Rapid photometric studies of the regions near open clusters M21 and M23" with Amalia Anderson, Luther College, 2003. Results presented at the Midstates Consortium for Math and Science Undergraduate Research Symposium, University of Chicago, November 2003.

"Effect of atmospheric conditions on stellar photometry from a low altitude site" with Scott Roland, Luther College, 2003.

"Stellar occultation techniques to search for Kuiper Belt Objects" with Heather Lehmann, Luther College, 2001-2003. Results presented at the National Conference on Undergraduate Research, University of Utah, March 2003.

"The feasibility of using small telescopes to detect planets in other stellar systems" with Travis DeJong, Dordt College, Zebadiah Howes, Buena Vista University and Matt Fitzgerald, Luther College, 2002.

"Spectrographic monitoring of supernovae" with Jami McLaren, Luther College, 2001-2002.

"Quantifying the infrared scintillation emission from xenon" with Jami McLaren, Luther College, 2001. Results presented at the National Conference on Undergraduate Research, Whitewater, April 2002.

"Development of an astronomical spectrograph" with Dan Bahr, Ryan Flynn and Jami McLaren, Luther College, 2000-2001. Results presented at the National Conference on Undergraduate Research, University of Kentucky, March, 2001 and at the R.J. McElroy Faculty/Student Research Symposium, Wartburg College, May 2001.

"Using photomultipliers to improve energy resolution in a xenon gas scintillation proportional counter" with Phil Assmus, Luther College, 2000. Results presented at the National Conference on Undergraduate Research, University of Kentucky, March 2001.

"Development of data acquisition and analysis software and an observing plan for a remote observatory" with Robyn Siedschlag, Luther College, 2000. Midstates Consortium for Math and Science Undergraduate Research Symposium, Washington University, October 2000.

"Hardware calibration and development of an observing plan for a remote observatory" with Siri Thompson, Luther College, 2000. Midstates Consortium for Math and Science Undergraduate Research Symposium, Washington University, October 2000.

"Quantifying the infrared scintillation emission from xenon" with Ujjwal Raut, Luther College, 2000.

"Optimizing methane-based plane-parallel proportional counters for the detection of xenon scintillation light" with Fred Agyepong-Yeboah, Luther College, 2000.

"Hardware development for X-ray astronomy" with Sarika Bajoria, Luther College, 1999.

"Development of a search for cluster-based variable stars" with Hilary Teslow, Luther College, 1999.

"Electronics contributions to energy resolution in a xenon gas scintillation proportional counter", with Angela Reisetter, Luther College, 1999.

"Study of quantum efficiency and proportional counter behavior dependence on CsI photocathode thickness", with Chad Reinertson, Luther College, 1999.

"Energy resolution limits in a xenon gas scintillation proportional counter" with Alex Phelps, Luther College, 1998-99. Results presented at the R.J. McElroy Faculty/Student Research Symposium, Wartburg College, May 1999.

"Search for infrared scintillation emission from xenon" with Ujjwal Raut, Luther College, 1998. Results presented at the National Conference on Undergraduate Research, University of Rochester, April 1999.

"Application of a pulse-fitting algorithm to data from a xenon gas scintillation proportional counter" with Brent Olson, Luther College, 1998.

 

Recent Publications:

Darrel B. Hoff and Jeffrey A. Wilkerson, Contemporary Activities in Astronomy (4thEd.), Kendall/Hunt Publishing Co., Dubuque, IA, 2009.

 J. Wilkerson, J. McLaren and U. Raut, "Measurement of the Near Infrared Xenon Scintillation Yield Near Atmospheric Pressure," Nucl. Inst. and Meth. A., 500, pp. 345-350, 2003.

J. Wilkerson, T.K. Edberg, J. Hamm, B.  Sadoulet, P. Shestople and G. Smith, "Study of High-Pressure Xenon Gas Scintillation Drift Chambers with Wave-shifting Fiber and CsI Photocathode Readouts," SPIE Conference Proceedings, 2806, pp. 361-371, 1996.

T.K. Edberg, S.E. Boggs A. Parsons, B. Sadoulet, P. Shestople, R. Therrien, S. Weiss, J. Wilkerson, and G. Smith, "Progress on the Scintillation Imaging Gas-filled Hard X-ray Telescope (SIGHT)," SPIE Conference Proceedings, 2280, pp. 406-411, 1994.

 

 

Once upon a time in a land far away, I wrote a sky watching column for the newsletter of the Center for Particle Astrophysics, an NSF science and technology center.  I remember when I was about middle school aged and John Cougar Mellencamp (who grew up about twenty miles from where I grew up) had one of his first hits.  It got much airtime in our neck of the woods and I recall a DJ saying he appreciated the way Mellencamp let his band wail away at the beginning before jumping in to sing.  I think of my newsletter columns much the same way.  I am appreciative of the way the editorial staff let me ramble on about my life for pages before finally mentioning a line or two about the night sky.  Here are few of my later columns, written after I had already lost my edge from years writing them: ketchup.html, perseids.html, revelations.html.

Astronomy Homepage

Physics Homepage