RESEARCH NEWS

Recent Publications (by group)

SOLID STATE:

M. Abolfath, T. Jungwirth, J. Brum, and A.H. MacDonald, “Theory of Magnetic Anisotropy in III_1-xMn_xV Ferro magnets,” Phys. Rev. B 63, 054418 (2001).

M. Abolfath, Kieran Mullen, and H.T.C. Stoof, “Massive skyrmions in quantum Hall Ferro magnets,” Phys. Rev. B 63, 075315 (2001).

M. Abolfath, T. Jungwirth, and A.H. MacDonald, “Mean-field theory of magnetic properties of Mn_x III_1-x V semiconductors,” Physica E 10, 161 (2001).

M. Abolfath and A. Langari, “Quantum Ferrimagnets in magnetic field,” Phys. Rev. B 63, 144414 (2001).

R. Khomeriki, M. Abolfath, and K. Mullen, “Solitons in polarized double-layer quantum Hall systems,” Phys. Rev. B 65, 121310 (2002).

S.A. Solin, D.R. Hines, J.S. Tsai, Yu. A. Pashkin, S.J. Chung, N. Goel and M.B. Santos, “Room Temperature Extraordinary Magneto resistance of Non-Magnetic Narrow-Gap Semiconductor/Metal Composites: Application to Read-Head Sensors for Ultra High Density Magnetic Recording,” IEEE Transactions on Magnetics 38, 89 (2002).

J.C. Keay, S.J. Chung, M.B. Santos, and M.B. Johnson, “Mobility anisotropy in InSb/AlInSb single quantum wells,” M.A. Ball, Applied Physics Letters 80, 2138 (2002).

HIGH ENERGY:

V.M. Abazov, B. Abbott, ... P. Gutierrez, ... M. Strauss (D0 Collaboration), “Subjet Multiplicity of Gluon and Quark Jets Reconstructed Using the kT Algorithm in pbarp Collisions,” Phys. Rev. D {65} 052008 (2002)

V.M. Abazov, B. Abbott, ... P. Gutierrez, ... M. Strauss (D0 Collaboration), “The Inclusive Jet Cross Section in pbarp Collisions at sqrt(s)=1.8 TeV Using the kT Algorithm,” Phys. Lett. B {525}, 211 (2002)

V.M. Abazov, B. Abbott, ... P. Gutierrez, ... M. Strauss (D0 Collaboration), “Search for Leptoquark Pairs Decaying into neutrino-neutrion + jets in ppbar Collisions at sqrt(s) = 1.8 TeV,” Phys. Rev. Lett. {88}, 191801, (2002)

V.M. Abazov, B. Abbott, ... P. Gutierrez, ... M. Strauss (D0 Collaboration), “Search for the Scalar Top Quark in ppbar Collisions at sqrt(s) = 1.8  TeV,” Phys. Rev. Lett. {88}, 171802, (2002)

V.M. Abazov, B. Abbott, ... P. Gutierrez, ... M. Strauss (D0 Collaboration), “Direct Search for Charged Higgs Bosons in Decays of Top Quarks,” Phys. Rev. Lett. {88}, 151803, (2002)

V. Barger, F. Halzen, D. Hooper, and C. Kao, “Indirect Search For Neutralino Dark Matter With High-Energy Neutrinos,” published in Phys. Rev. D65, 075022 (2002).

K.A. Milton, I.L. Solovtsov, O.P. Solovtsova, “Remark on the Perturbative Component of Inclusive Tau Decay,” Phys. Rev. D 65, 076009 (2002)

Kimball A. Milton, George R. Kalbfleisch, Wei Luo, Leonard Gamberg, “Theoretical and Experimental Status of Magnetic Monopoles,” Invited talk given at 5th Workshop on Quantum Field Theory Under the Influence of External Conditions, Leipzig, Germany, 10-14 Sep 2001, Int. J. Mod. Phys. A 17, 732-750 (2002)

Kimball A. Milton, Sergei D. Odintsov, Sergio Zerbini, “Bulk Versus Brane Running Couplings,” Phys. Rev. D 65, 065012 (2002)

ASTROPHYSICS:

Yun Wang, & Geoffrey Lovelace, “Unbiased Estimate of Dark Energy Density from Type Ia Supernova Data,” ApJ, 562 (2001), L115

P. H. Hauschildt, D. K. Lowenthal, and E. Baron, “Parallel Implementation of the PHOENIX Generalized Stellar Atmosphere Program III: A Parallel Algorithm for Direct Opacity Sampling,” Ap. J. (Supplements), (2001), 134, 323--330.

R. Mitchell, E. Baron, D. Branch, P. Lundqvist, S. Blinnikov, P. H. Hauschildt, and C. S. J. Pun, “Ni Mixing in the Outer Layers of SN 1987A,” Ap. J., (2001), 556, 979--986.

E. J. Lentz, E. Baron, D. Branch, and P. H. Hauschildt, “NLTE Synthetic Spectral Fits to the Type Ia Supernova 1994D in NGC 4526,” Ap. J., (2001), 557, 266--278.

A. Hun-Bon-Hoa, F. LeBlanc, P. H. Hauschildt, and E. Baron, “Radiative Acceleration in Stellar Atmospheres,” A&A, (2002), 381, 197--208.

T. Barman,  P. H. Hauschildt, A. Schweitzer, P. Stancil, E. Baron, and F. Allard, “Non-LTE Effects of Na I in the Atmosphere of HD209458b,” Ap. J. (Letters),  (2002), 569, L51-L54.

Branch, D. et al., “Direct Analysis of Spectra of Type Ib Supernovae,” ApJ, 566, 1005 (2002)

Richardson, D., Branch, D., Casebeer, D., Millard, J., Thomas, R. C., and Baron, E., “A Comparative Study of the Absolute Magnitude Distributions of Supernovae,” AJ, 123, 745 (2002)

Thomas, R. C., Kasen, D., Branch, D., and Baron, E., “Spectral Consequences of Deviation from Spherical Composition Symmetry in Type Ia Supernovae,” ApJ, 567, 1037 (2002)

C. Sneden, J. J. Cowan, J. E. Lawler, S. Burles, T. C. Beers and G. M. Fuller, “Europium Isotopic Abundances in Very Metal-poor Stars,” Astrophys. J. Letters, 566, L25(2002)

Colloquia, Papers Presented

Lloyd Bumm presented “Molecular Insulators, Wires, and Switches,” invited speaker, Joint Physics and Chemistry Seminar, Oklahoma State University, 21 Jan 2001, Stillwater, OK.

Kim Milton presented the seminar “Entropy Bounds in R x S³ Geometries,” OU, February 20, 2002. Chung Kao presented a colloquium on “The Higgs Challenge,” and a seminar on “Indirect search for neutralino dark matter with high-energy neutrinos,” in April 2002, at the University of Kansas.

John Cowan presented two talks: 1) “Abundances and Ages of the Oldest Stars,” University of North Carolina, Chapel Hill, NC (March 2002); and 2) “Neutron-Capture Elements Abundances in Halo Stars and the Age of the Galaxy,” MIT, Cambridge, MA, in April 2002.

Yun Wang presented "Probing Dark Energy With Type Ia Supernovae,” at Columbia University in March, 2002, and the University of Florida, April, 2002; and “Probing Fundamental Physics with Cosmological Data,” University of Texas at Dallas, Feb., 2002.

Ed Baron recently gave the following talks: 1) “Measuring Cosmological Parameters with Type II Supernovae: Calibration of SN 1987A,” Center for Simulational Physics Seminar at University of Georgia, Dec., 2001; 2) “Understanding Spectra of SNe Ia,” seminar at ENS-Lyon, Lyon, France, Jan., 2002; and 3) “Parallelization Strategies for ALI Radiative Transfer in Moving Media,” at meeting on “Stellar Atmosphere Modeling,” Tübingen, Germany, March, 2002.

Meetings Attended

Chung Kao attended the 5th International UCLA Symposium on Sources and Detection of Dark Matter and Dark Energy in the Universe (Dark Matter 2002), February 20 - 22, 2002, Marina del Rey, California. He presented the paper “Indirect search for neutralino dark matter with high energy neutrinos.”

Lloyd Bumm, Sheena Murphy, Kieren Mullen, Matt Johnson, and Mike Santos attended the Oklahoma NSF EPSCOR Annual Conference:  Functional Genomics Resources Consortium & Network for Nanostructured Materials, 16 May 2002.

John Cowan attended: 1) the Eleventh Workshop on Nuclear Astrophysics, Ringberg Castle at Lake Tegernsee, Germany (February 2002) and presented “The r-Process and Chronometers,” with co-authors C. Sneden and J. W. Truran; and 2) Low Z at Low z and High z: Early Chemical Evolution, Minneapolis, MN  (March 2002) “The r-Process and Nucleochronology.”

Rollin Thomas attended the Workshop on Stellar Atmospheres in Tübingen, Germany, from April 8-12, where he presented a poster entitled “Synthetic spectra from 3D models of supernovae.”

Ed Baron attended a meeting on Stellar Atmosphere Modeling, Tübingen, Germany, Mar. 2002.

Ramin Abolfath attended the March APS meeting in Indianapolis and gave four talks: 1) “Anisotropic magneto resistance of (III, Mn) V Ferro magnets,” 2) “Global phase diagram of bilayer quantum Hall Ferro magnets,” 3) “Microscopic Theory of Critical Currents in Quantum Hall Super fluids,” and 4) “Theory of optical conductivity of (III, Mn) V ferromagnetic semiconductors.”

Mike Santos’ group attended the APS March Meeting in Indianapolis on March 18-22, and made three presentation: 1) Mike Santos presented a talk entitled “Spin- and cyclotron resonance in symmetric and asymmetric InSb quantum wells: resolving the Rashba spin Splitting,” by M. B. Santos, G. A. Khodaparast, R. E. Doezema, S. J. Chung, and K. J. Goldammer; 2) Niti Goel presented a talk entitled “Ballistic electron transport in InSb quantum wells,” by N. Goel, S. J. Chung, M. B. Santos, K. Suzuki, S. Miyashita, and Y. Hirayama; 3) Tetsuya Mishima presented a poster entitled “Structural and Electronic Properties of AlInSb/InSb Quantum Wells Grown on GaAs (001) Substrates,” by T.D. Mishima, J.C. Keay, N. Goel, M.A. Ball, S.J. Chung, M.B. Johnson, and M.B. Santos.

Ryan Doezema attended the March APS meeting in Indianapolis.

Karen Leighly and Darrin Casebeer attended the FUSE Science and Data Workshop, March 20-22, at JHU in Baltimore, MD. Darrin presented a poster entitled “FUSE Observations of Narrow-line Seyfert 1 Galaxy RE 1034+39,” D. Casebeer & K. M. Leighly

Karen Leighly attended the FUSE Observers Advisory Committee meeting on March 19, from which she reports that the major development has been the recovery of the satellite operations after the loss of two reaction wheels in late 2001.

Kim Milton attended the April, 2002, meeting of APS, Albuquerque, to explore the possibility of publishing another book (this time with Springer Verlag) on Schwinger's contribution to classical and quantum radiation theory.  Hopefully, the project will be finalized by the end of the summer.

Dick Henry attended the conference Low Z at Low z and High z: Early Chemical Evolution, Minneapolis, MN  (March 2002)

Visitors at Nielsen 

Yun Wang hosted two visitors recently: Hume Feldman, from the University of Kansas, March, 2002, with whom she discussed the study of the large scale structure in the Universe; and Daniel Holz, from the Institute for Theoretical Physics, Univ. of California, Santa Barbara, in October, 2001. with whom she is collaborating on the study of weak gravitational lensing of supernova.

Jochen Sigmund, a graduate student from Darmstadt University in Germany visited Mike Santos’s group for two weeks in April to learn about growth of InSb-based heterostructures by molecular beam epitaxy.

Yoshiro Hirayama, from NTT Basic Research Laboratories in Japan, visited from May 9 to 12 to discuss collaborations with the solid-state group.  He gave a solid-state seminar entitled “Nanomechanical Systems and Nanoprobing of Electron-Wave Features Based on InAs Heterostructures”.

Ed Baron hosted Sebastien Bongard from Lyon, France. Sebastien liked the department so much that he is getting a dual Ph.D degree from OU and Lyon.

Karen Leighly hosted Andrzej Zdziarski from N. Copernicus Astronomical Center, February 21 and 22.  They worked on the Chandra observation of the Narrow-line Seyfert 1 galaxy 1H0707-495.

Grants Awarded        

Eric Abraham and Neil Shafer-Ray were awarded $488,000 from the DEPSCoR program through the Office of Naval Research for studies of Methods to cool and Trap Atoms and Molecules.

Kim Milton: US Department of Energy, Nonperturbative Quantum Field Theory, $98,000 (April 1, 2002-March 31, 2003)

Ed Baron: NASA, LTSA supplement to Multi-Wavelength Modeling of Supernovae, $20,000

Oct. 1, 2001-Sep 30, 2002

Research Travel

Eric Abraham helped with the Office of Naval Research Program Review, April 28 - May 1, in Arlington, VA, on Development of Methods to Cool and Trap Atoms and Molecules.

Brad Abbott has been traveling to Fermilab every two weeks to attend meetings and discuss progress with colleagues.  A number of conferences are approaching, including an international DØ workshop at OU, July 8-12, and Brad has been busy organizing speakers and approving new results.

Ed Baron visited the University of Georgia in December where his long-term collaborator Peter Hauschildt has been for the last six years. Peter is moving to Hamburg, Germany, so future visits will be less frequent and require longer plane rides.

Dick Henry reviewed proposals in space physics in Washington for the National Research Council, March.

Summer Plans

Lloyd Bumm plans to spend the summer setting up his lab.

Eric Abraham says, “We will have five new graduate students working on the cold molecule collaboration this summer.  It is a very exciting time.”

Rollin Thomas plans to travel to Leiden, the Netherlands, in July, for a workshop on supernovae, and then go to a short meeting in Munich on Type Ia’s.

Brad Abbott’s summer plans are to travel to Fermilab as much as possible in order to get results ready for summer conferences. Says Brad, “A large workshop for his experiment will be taking place at OU this July [see above] so it will be a busy summer.”

Yun Wang plans to do research on cosmology, and supervise one REU student, in addition to one graduate student.

Kim Milton will work with Carl Bender for a week at Washington University on novel approaches to quantum field theory.  Then he'll spend a week at the DPF meeting at William & Mary.  At the end of June, he will attend the Sakharov Conference in Moscow, followed by a short visit to the General Relativity and Gravitation meeting in Tomsk, Siberia.

Mike Strauss is still spending about half his time at Fermilab doing research with the D0 collaboration.  He will maintain this schedule, more or less, until fall.

Research Breakthroughs

Eric Abraham reports that, “With the Shafer-Ray group, we recently demonstrated a new method of producing ultra cold samples of any Para-magnetic gas.  Two of the last five Nobel prizes has gone towards experiments using ultra cold gases, but the methods rely nearly exclusively on alkali metals.  The experiments conducted in our collaboration may open up these experiments to the rest of the periodic table, as well as molecules.”

Dick Henry and Jason Prochaska (Carnegie Observatories) have discovered evidence, which suggests that star formation in the early universe was characterized by the formation of proportionately more massive stars than is the case in recent times.

MULLEN TO CAMAROON

OU has many students from Cameroon on campus, and a few of them in this department. Based upon this connection, Kieran Mullen was contacted by Prof. Jean-Marie Ndjaka, a professor at the University of Yaounde in Cameroon. They wrote a grant together to the International Programs office of the National Science Foundation, which was funded. Prof. Ndjaka visited OU for about three months. An experimental physicist by training, he was interested in moving towards doing theoretical research. Prof. Mullen in turn will visit Cameroon for two weeks this summer. Kieran is also the Chair of Graduate Recruiting.  By establishing a connection between the two campuses he hopes to provide an opportunity for talented African students to come to study at OU.  Located in equatorial West Africa, Cameroon is about the size of California. It has a population of 16 million. It has a history of French and English colonization, so both languages are spoken there.

Prof. Mullen will be making a similar trip to the Republic of Georgia next year, based upon a different grant program.

TEACHING NEWS

From Eric Abraham: “The class coming into 1205 in the fall of 2001 was one of the largest we

have seen for some time with over 40 students.  Hopefully, this is signaling a trend to more graduates of the program in the future.” From Kim Milton: “I taught Quantum Field Theory over internet-based interactive video. I had seven students at OU, and four at OSU.  The technology still leaves much to be desired, as it's hard to do better than using a large blackboard. Instead, I had a small board with markers (often dry), which the students in Stillwater had to read with a rather low-resolution camera.  Distance learning still has a long way to go, or maybe that’s the problem!”

Ed Baron says, “I really enjoyed teaching Stellar Atmospheres” [in the spring].

David Branch, Ed Baron, and John Cowan presented lectures on cosmology and the early universe in April as part of the Faculty In Residence program.

BITS FROM NIELSEN HALL NETWORK                     

Our computer network has a bit more - and a bit less - than it formerly did.  On the bit more side, we have grown to a total of 39 Sun workstations (with more on the way) including 10, which are available in the grad student offices in Room A201.  Our total number of Unix systems currently stands at 55 including our losses mentioned next.

On the bit less side, we have bid farewell to our IBM SP2 system.  The hardware was not supported by the versions of AIX, which IBM updates and so no new security fixes were available.  The SP2 was hacked into because of this and it was deemed best to simply shut it down.  The new OU supercomputer center (see http://www.oscer.ou.edu/) will be up and running soon to provide the support for our high-end computer users.

Andy Feldt

LARGE INTERACTIVE CLASSES

This past semester, an intrepid group of physics and astronomy faculty members participated in an experiment to change the dynamics of large lecture classes.  Wireless voting systems were installed in the two new large lecture halls in Nielsen. Students vote using small infrared remotes, their answers are recorded by a computer in the classroom, a histogram of their answers can be displayed immediately after the vote is done to stimulate class discussion, and the answers of each individual student is recorded for analysis and grading.  The goals of the system are to make a large class experience more personal and engaging for the students, and to better match the content and pace of the class to what students do or do not understand.  Similar voting systems have been used at other schools for a few years, but this was a new adventure for our department. Participating in the project were Karen Leighly (Astro 1504/1514), Stu Ryan (Phys1114) Lloyd Bumm (Phys 2414), Kieran Mullen (Phys 2424), Pat Skubic (Phys 2514), Bruce Mason (Phys 2524), and approximately 1,400 students. Despite technical problems with the system, the reviews of the participants were generally positive.  In two classes where surveys were taken of students, 70 - 80% of the responses rated the system as either useful or very useful.  All the instructors reported much better attendance in class and most were certain they would use the system again.

Special thanks go to Stu Ryan and Bill See for their efforts installing the system the week before classes started, and to the department and the College of Arts & Sciences for funding the purchase of the system.

Bruce Mason

MASON UPGRADE

Since January 1, Bruce Mason has been the Director of the Physical Sciences Resource Center (PSRC) of the American Association of Physics Teachers.  The PSRC is an online collection, or “digital library,” of resources to help teachers of physics and astronomy.  It contains materials and links to syllabi, assessments, demos, labs, online learning objects, and education research.

Bruce’s first four months on the (half-time) job were spent writing a grant to support the growth of the collection.  The summer will be spent redesigning the site to make it more dynamic and user friendly.  The PSRC is online at

http://www.psrc-online.org.

This position grew out of Bruce’s involvement with the MERLOT project (Multimedia Education Resource for Learning and Online Teaching), an international collaboration to create a multi-discipline, peer-reviewed digital library of online learning objects.  Started in the mid-1990's by the California State University system, MERLOT has been operating in its current form for about three years.  Bruce has been one of the lead editors on the physics editorial board since this time.  MERLOT is online at http://www.merlot.org.   Anyone interested in finding out more about MERLOT, please feel free to contact Bruce at: (mason@nhn.ou.edu).  He would particularly like to talk to anyone with an interest in becoming a reviewer.