From The Chairman

Dr. Paul Hiack

Welcome to the first edition of our Newsletter!  So much has been happening in and around the Department, we decided that an annual Newsletter would provide a good way for keeping in touch with our graduates, former faculty, and other friends.  If you have not been back to visit lately, you would be surprised at the changes that have taken place.

 One conspicuous change is the increased number of Physics Majors.  There are currently 38 students enrolled in one of four different programs we now offer: Liberal Arts Physics, Computational Physics, Physics Teaching, and our recently added program in Earth Science.  Most physics majors get involved in various research programs guided by faculty that eventually lead to scientific publications.

 There have been several new faculty members.  Dr. Thulsi Wickramasinghe, an astrophysicist from the University of Pennsylvania, and Dr. Marty Becker, a geologist from the City University of New York, joined our Department in September 1997.  As you perhaps already know, Dr. Snezana Dalafave, a solid state physicist from the Florida State University joined our department in September 1995, while Dr. Romulo Ochoa, an optical spectroscopy and computer-modeling physicist from the Catholic University of America, came in 1992.  Elsewhere in this issue are articles describing research activities in the Department.  An experimental program along with individuals working on theoretical problems contributes to an exciting and stimulating atmosphere at the Department.

 A new $35 million Science Complex is being built adjacent to Crowell Hall.  It will encompass new Biology, Chemistry, and Physics and Mathematics buildings.  This complex will provide us with various classroom and laboratory facilities for student research and education.  It will also include a Zeiss Planetarium that will be used in our astronomy courses.  We are constantly re-evaluating the manner in which our teaching and research are being conducted.  New courses are being planned, and we are on the lookout for ways to educate our students in a more productive manner.  In future issues of this Newsletter we will report on these activities as they develop.  Meanwhile, check out our Web page at http://www.tcnj.edu/~physics/.

 Tell us what is happening with you or other alumni with whom you might have contact.  For your convenience, a reply card is included.  You can also send us e-mail at physics@beast.tcnj.edu.  Let us hear from you!

 

Faculty Research and Activities

  

Dr. Martin Becker has been studying Creta-ceous chondrichthyans to explain feeding related pathologies to fossil teeth of ancient sharks and their dietary behavior based on co-occurring osteichthyan, arthropod, mollusk and reptile fossils. He is also collecting and analyzing microvertebrate chondrichthyan and osteichthyan teeth, scales and fragments. These studies involve field and laboratory work.  Dr. Becker's research also involves studying mineral deposits. His recent publications are:
"Mixing of Santonian, and Campanian Chondrichthyan and Ammonite Macrofossils along a Transgressive Lag Deposit, Greene County, Western Alabama" (with W. Slattery and J. Chamberlain). 1998, Southeastern Geology, 7, 1.
"Recent Mineral Finds at the Millington Quarry, Sommerset County, New Jersey."  1998, Rocks and Minerals, 73, 320.

Dr. Snezana Dalafave's research focuses on materials preparation and measurement of transport properties. Currently this includes preparation of thermoelectric semiconductors, such as transition metal chalcogenides, using solid state reactions. The electrical resistivity, thermoelectric power, and Hall mobility of these materials are measured as functions of temperature, composition, and magnetic field.  Her recently published studies are: "Seebeck Coefficient and Electrical Resistivity in Re₆Te_15-xSe_x at Room Temperature" (with J. Ziegler), 1998, Journal of Materials Science Letters, 17, 1463-1465.
"Thermoelectric Properties of Re₆Te₁₅ and Re₆Se₈Te₇ Cluster Compounds," 1998, Materials Letters, 37, No. 4-5, 177-181.
"Thermoelectric Properties of Doped Rhenium Chalcogenides Re₆M_xTe_15-xSe_x (x = 0,1,2; M= Ga, In, Ag)," (with H. Barcena, and D. Henningsen),  T.M. Tritt, H. B. Lyon, Jr. G. Mahan, M.G. Kanatzidis, eds., 1998, Proceed. Materials Research Society, 545, 203.

  Dr. Ron Gleeson has been serving as a consultant for the US Navy for over the past ten years. He has been working on a wide variety of very challenging problems doing systems analysis. His latest efforts are towards developing an improved system for automated, perspective-independent object recognition. The following are some results of his research:
"Determining the Rank of a Noisy Square Matrix Using the Characteristic Coefficients" (with P. F. Stiller and R. M. Williams), 1996, U. S. Navy Tech. Pub., #NAWCADWAR-96-21-TR.
"Wedge Theory/Compound Matrices: Proper-ties and Applications" (with D. L. Boutin and R. M. Williams), 1996, U. S. Navy Tech. Pub., #NAWCADPAX-96-220-TR.

  Dr. Fred Goldstein has published 3 books over the last 2 years.  They include an introduction to geology, "The New Jersey Workbook", and "Energy and the Environment".  He has presented papers at regional conferences including the Geological Association of New Jersey.  Recently, he was an enrichment lecturer for a major cruise line.

  Dr. Paul Hiack is the chairman of our department and is also the director of the observatory. The observatory operates a 36-seat planetarium, a 14” Celestron telescope, a 16” Kline telescope and several smaller telescopes and is a major part of the astronomy curriculum. Recently, he has devoted much time to the planning of the facilities for the department in the new science complex.  Among these facilities are a new Zeiss planetarium and various astronomical and computing facilities.

  Dr. Frank Kolp works in the area of science education. This involves the development and testing of physics curricular materials for use in the classroom and the laboratory. Both commercial and locally developed equipment are tested and frequently added to the existing program.  His recent publications are:
"The Computer Mouse as a Data Acquisition Interface: Application to Harmonic Oscillators,” (with R. Ochoa), 1997, American Journal of Physics, 65,11.
 "A Mouse in Our Laboratory," (with R. Ochoa), 1996, The Physics Teacher, 34.

  Dr. Romulo Ochoa’s work involves optical spectroscopy and computer simulations. Optical techniques (Raman and photoluminescence) are used to investigate the effects of structure and size on the electronic and vibrational spectra of amorphous and crystalline samples. Studies are made of the dependence of temperature and incident light intensity on the samples' spectra.  Spectra are acquired using a CCD spectroscopic system in conjunction with a 5-Watt Argon Ion laser. The hybrid Montecarlo-Molecular Dynamics technique is used to simulate the structure of silicon carbide. The self-diffusion coefficients of carbon and silicon are studied using a FORTRAN code that has been developed. Changes in the coefficients are observed when defects are added or vacancies created in simulated SiC. The results are compared with lab experiments. The studies will aid in the understanding of the contribution of diffusion to the mechanical properties of SiC.  This on-going work has resulted in the following recent publication:
"Raman Characterization of CdTe Nano- crystallites Embedded in Glass Matrix",  Ochoa, R, et al.  1997, Journal of Materials Science Letters, 16, 613-616.

Raymond J. Pfeiffer studies the physics of interacting stars. Currently he is analyzing UV spectrophotometric images obtained with the International Ultraviolet Explorer (IUE) space-satellite telescope for several selected binary stars. This analysis includes employing a computer code to model the spectral absorption profiles caused by stellar winds in these systems. The research also involves the development of other computer codes that: (1) model the observed variable light of the system as the stars revolve around their common center of gravity (the light curves), and (2) model the wind-interaction effects that produce residual absorption in the wind spectral profiles.  The following works have resulted from such on- going research:
"The Winds of Hot, Close Binaries; Paper 3: HD 159176," (with. Pachoulakis, R. H. Koch  and D. J. Stickland), 1997 Observatory, 117, 301.  
"Winds in Massive, Main Sequence, Close Binaries," (with R.H. Koch, I. Pachoulakis, and D. J. Stickland), in "Workshop on Colliding Winds in Binary Stars",  LaPlata,  Argentina, Nov. 1995, V. Niemela and N. Morrell eds.,  Revista Mexicana de Astronomia  Astrofisica   Serie de Conferencias  (RMAASC), 1996.
"The Winds of Hot, Close Binaries; Paper 2: CW Cephei," (with I. Pachoulakis, R. H. Koch, and D. J. Stickland), 1996, Observatory, 115, 89.

Dr. Thulsi Wickramasinghe concentrates his research in theoretical cosmology and general relativity. He has done various studies analyzing gamma-ray bursts. He also works on gravitational lensing of various objects. His latest ambition is to extend the theory of gravitational lensing to include relativistically-moving objects.  His recent works are:
"Gross Spectral Differences Between Bright and Dim Gamma-Ray Bursts,"  1997, Astro-physical Journal Letters, 435, L133. 
"Perihelion Advance of Mercury and the Cosmological Constant,"  1998, Proceedings of the Super Vatican Observatory Summer School.

 

Feature Article

 

Gamma-Ray Bursts: The Most Violent Explosions in the Universe

 

By:  Dr. Thulsi Wickramasinghe

 

Gamma-ray bursts (GRBs) have been perhaps the biggest astronomical mystery since their first detection by the Vela satellite about thirty years ago. Despite many technological advances made in their detection during the past few years, we have been unable to understand what produces them.

NASA launched the Burst and Transient Source Experiment (BATSE) on board the Compton Gamma Ray Observatory in 1991 for the exclusive study of these mysterious bursts. BATSE has so far observed over 2000 GRBs occurring randomly in the sky with an unprecedented rate of one a day! This means that the GRBs cannot be confined to our own galaxy.  They must then originate at far reaches in the universe and must participate in the general expansion of the universe.  The expansion makes the duration of the very distant and therefore dim bursts to be stretched longer in time. It also makes the observed number of dim bursts to be fewer than would otherwise be expected. Furthermore GRBs are short lived. Their life times are of the order of only a few milliseconds, and they emit their light only in gamma rays, which are the highest energy rays of the electromagnetic spectrum and are not directly visible by eye.  The short durations of the bursts imply that they are very small. All these facts are fantastically verified by BATSE observations proving that GRBs are cosmological.

The short durations and cosmological distances of GRBs make them the most violent fireball explosions in the universe. Calculations show that a typical burst pours out in a few milliseconds an energy larger than that emitted by the sun in its entire lifetime!

If they are so powerful, what kind of physical processes could produce them? The most accepted theory is that such energies could be produced in spiraling merges of neutron stars, which are about 20 km in diameter and a few times more massive than the sun. The very last phases of such mergers to form blackholes can even outshine a billion galaxies like the Milky Way combined!

This is why GRBs are thought to be massive explosions perhaps second only to the big bang, the very event that gave birth to the entire universe!  They have become so mysterious because we do not yet understand their physical mechanism. This is why they are among the most interesting astronomical phenomena. 

Student Research and Plans

  Margaret Benoit, a graduating senior physics major, worked with Dr. Wickramasinghe last fall on a problem in general relativity investigating bounds that can be placed on the cosmological constant from planetary motions. This research has resulted in the paper:  "Contribution of Vacuum Field to Planetary Motions," (with T. Wickramasinghe), 1999, Astrophysics & Space Science (in press).  This spring, Margaret again worked with Dr. Wickramasinghe studying spectrophotometric properties of Gamma-ray Bursts. This coming fall, Margaret begins graduate studies in geophysics at Penn State.

David Bucko, a graduating senior physics major, worked with Dr. Ochoa this past spring semester studying Raman and Photolumine-scence Spectra of Quartz.

Brian Cahill, a senior Physics Major, worked under Dr. Becker during the spring semester studying satellite images from the internet as a means for interpreting various weather phenomena. Last fall, Brian worked with Dr. Dalafave on the transport properties of mixed rhenium chalcogenides.

Ryan Earley, a sophomore physics major, worked with Dr. Wickramasinghe during this past spring semester to develop a CCD astrophotography project.                             

Adrian Griegal, a graduating senior physics major, studied some topics with Dr. Gleeson last fall that are not covered in our undergraduate quantum mechanics courses. He developed computer simulations showing the reflection and transmission of a pulse-like wave function that occurs when it impacts upon a finite barrier.  Last fall, Adrian also worked with Dr. Pfeiffer and analyzed the light curves for several narrow ultraviolet bandpasses in the spectra of the hot binary system known as Delta Orionis. This analysis revealed a highly turbulent outflow of wind from each star in the system.

Peter Dorofy, a graduating senior physics major, worked with Dr. Wickramasingle last fall studying the masses of Machos as derived from the pulse heights and times of gravitational lensing effects on stars.  This work has resulted in a publication:  "Lensing of Stars Within Quasars Can Mimic Their Optical Fluctuations," (with T. Wickramasinghe), 1999, Astrophysics and Space Science, in press. He also worked with Dr. Ochoa on a set-up for CCD astronomy.  This coming fall, Peter begins a career teaching high school physics.

Thomas Jeffrey, a junior physics major, worked with Dr. Ochoa this spring on a hybrid Monte-Carlo simulation of silicon carbide.

Eugene Lera, a junior physics major, worked with Dr. Ochoa last fall studying laser intensity effects on the Raman spectra of amorphous As₂Se₃.

David Pustai, a graduating senior physics major, worked with Dr. Ochoa studying the theory and application of Fourier Optics.  Last fall, Dave again worked with Dr. Ochoa on the data reduction of temperature dependent Raman spectra. Dave begins graduate school in physics at the University of  Delaware this coming fall.

Michelle Reno, a junior physics major, worked with Dr. Wickramasinghe this spring to observe variable stars using the telescopes of the College.  She also worked with Dr. Ochoa on a quantification of Lenz's Law.

Steve Schwartz worked with Dr. Dalafave this past spring semester studying the temperature dependence of the Seebeck coefficient and resistivity of doped rhenium tellurides.

Michael Vergara, a junior physics major, worked with Dr. Ochoa this spring on the automation of an optical spectroscopy system using the software LAB VIEW.

 

Physics Alumni News

1995 – Timothy Samuels has received his M.S. from Brigham Young University.  Currently, Tim is working on his Ph.D. in signal processing at the University of Karlskone in Sweden.  His e-mail address is (samuels@tcnj.edu) .

1996 – Paul McCracken has graduated from Wright State University with an M.S. in Physics/Medical Physics.  He is now at the Mayo Clinic and Foundation in Minnesota.  Paul  is doing his  Ph.D.  research in Magnetic Resonance Elastography.  Paul may be reached at (mccracken.paul@mayo,edu)

1997 – Jill Ziegler is in her next-to-last semester for an M.S. degree at Northern Illinois University.  Her thesis is in high-energy physics.  (ziegler@niuhep.physics.niu.edu)

1998 – Lorrie Blondo and Laura Sprague are teaching physics as Bridgewater-Raritan High School and Phillipsburg High School respectively.