Dr. Sandra J. Quintanilla
University of North Texas
Physics
(940) 565-4739
Email:

Education

PhD, Royal Hollowayand Bedford New College, Universityof London, 1986.
Major: Physics, "A Theoretical Study of Elastic Electron-Positronium Scattering and Photo-absorptionby thePositronium Negative Ion."
Dissertation Title: A Theoretical Study of Elastic Electron Positronium Scattering and Photo-absorption by the Positronium Negative Ion
BS, Royal HollowayCollege, Universityof London., 1983.
Major: Physics, Class 1 Honours

Professional Positions

Academic - Post-Secondary
Dr./Professor (Tenured)/Faculty Development Leave, University of North Texas. (January 2018May 2018).

Professional Memberships

Member, Division of Atomic, Molecular and Optical Physics of the American Physical Society (APS). (1993 – Present).

Texas Section of the APS, STX. (1993 – Present).

Topical Group on Few-Body Systems. (1993 – Present).

American Physical Society. (1987 – Present).

Executive committee member, Topical Group on Few-Body Systems. (20082011).

Previously board member, Topical Group on Few-Body Systems and Multi-particle Dy¬namics of the APS. (19891990).

Development Activities Attended

Faculty Development Leave,"Professor," University of North Texas, United States of America. (20182018).

Awards and Honors

Graduate student, Jason Hunnell, received a special recognition of his contributed paper. He receivedanawardof $200, Texas Section of the American Physical Society (APS), Texas Christian University. (20012001).

Selectedforappointment asaLongTerm Visitor, Smithsonian Astro¬physical Observatory's Institute for TheoreticalAtomic and Molecular Physics. (19991999).

Who's Who in Science and Engineering, 4th Edition. (19981999).

Selectedforappointment asa ShortTerm Visitor, Smithsonian Astro¬physical Observatory's Institute for TheoreticalAtomic and Molecular Physics. (19971997).

Who's Who Among America'sTeachers. (19961996).

Valerie Myserscough Prize, Universityof London. (19851985).

Valerie Myserscough Prize, Universityof London. (19841984).

Teaching

Teaching Experience

University of North Texas
PHYS 3310, Mathematical Methods in the Physical Sciences, 14 courses.
PHYS 4210, Electricity and Magnetism, 2 courses.
PHYS 4310, Quantum Mechanics, 21 courses.
PHYS 4900, Special Problems, 2 courses.
PHYS 4910, Special Problems, 5 courses.
PHYS 4950, Senior Thesis, 2 courses.
PHYS 4955, Senior Thesis Capstone, 1 course.
PHYS 5500, Quantum Mechanics I, 7 courses.
PHYS 5510, Quantum Mechanics II, 1 course.
PHYS 5900, Special Problems, 7 courses.
PHYS 5910, Special Problems, 8 courses.
PHYS 5920, Research Problems in Lieu of Thesis, 2 courses.
PHYS 5930, Research Problems in Lieu of Thesis, 1 course.
PHYS 6000, Mathematical Methods of Physics I, 2 courses.
PHYS 6900, Special Problems, 2 courses.
PHYS 6910, Special Problems, 5 courses.
PHYS 6940, Individual Research, 13 courses.
PHYS 6950, Doctoral Dissertation, 15 courses.

Non-Credit Instruction

Seminar. (July 10, 2018July 10, 2018).

Seminar. (April 11, 2018April 11, 2018).

Seminar. (April 27, 2017April 27, 2017).

Directed Student Learning

Other,"Positronium - Positronium Scattering," Physics. (2017 – Present).

Major Professor,"Electron- and Positron Impact Ionization of Hydrogen and Helium," Physics. (2017 – Present).

Major Professor, Physics. (2016 – Present).

Dissertation Committee Member,"On dissertation committee," Physics. (2015 – Present).

Dissertation Committee Member,"On Ph.D. dissertation committee," Physics. (20142018).

Other,"On Ph.D. dissertation committee," Physics. (20142018).

Supervised Research,"Positronium Formation in positron-hydrgen collisions," Physics. (20162017).

Undergraduate Honors Thesis, Physics. (20162017).

Other,"On Ph.D. dissertation committee," Physics. (2016).

Other,"Not. Project/Thesis/Dissertation.," Physics. (20152016).

Supervised Research, Physics. (20152015).

Other,"On Ph.D. dissertation committee,". (20122015).

Dissertation Committee Chair,"Dissertation. Variational Calculations of Positronium Scattering with Hydrogen," Physics. (20082015).

Other,"Was on Ph.D. dissertation committee,". (20032014).

Other. (20112011).

Supervised Research, Physics. (20072007).

Other. (20062006).

Other. (20052005).

Other. (20032003).

Other. (20012001).

Other. (19941999).

Other. (19941999).

Other,"(e, 2e) collisions project," Physics. (19971997).

Supervised Research,"(e, 2e) project," Physics. (19961997).

Other. (19941997).

Other. (19941997).

Other. (19941997).

Other. (19941997).

Other. (19941997).

Other. (19941997).

Awards and Honors

Nominated for: 2018-2019, Professor of the year, UNT Physics. (May 2019May 2019).

Research

Published Intellectual Contributions

Abstract for a conference
Ward, S. J., Van Reeth, P. (2016). Deep Minimum in the Differential Cross Section for Ps Formation in Positron-Hydrogen Collisions. 61(8), 193.
Abstract for a national conference
DeMars, C. M., Kent, J. B., Ward, S. J. (2019). Deep minimum in the Coulomb-Born TDCS for e$^-$-He and e$^+$-He ionization. Bulletin of the American Physical Society. 64(4), L01 13, 119 (1 pp)). http://meetings.aps.org/Meeting/DAMOP19/Session/L01.13
Ward, S. J., Alrowaily, A. W., Van Reeth, P. (2019). Multichannel Effective Range Theory Analysis of Zeros in the Positronium formation Scattering Amplitude for Positron-Hydrogen Collisions. Bulletin of the American Physical Society. 64(4), E01 32, 50-51 (2 pp). American Physical Society. http://meetings.aps.org/Meeting/DAMOP19/Session/E01.32
Medrano, G., Ward, S. J., Van Reeth, P. (2019). Variational Calculations of the Ps-Ps System. Bulletin of the American Physical Society. 64(4), S01 25, 193 (1pp). http://meetings.aps.org/Meeting/DAMOP19/Session/S01.2
Abstracts and Proceedings
Ward, S. J., Woods, D., Van Reeth, P. (2015). An Investigation of Positronium-Hydrogen Collisions. 60(7), 182-183. http://meetings.aps.org/link/BAPS.2015.DAMOP.Q1.112
Quintanilla, S. J. (2014). http://meetings.aps.org/link/BAPS.2014.DAMOP.Q1.55
Quintanilla, S. J. (2014). http://meetings.aps.org/link/BAPS.2014.GEC.MW1.7
Quintanilla, S. J. (2014). http://meetings.aps.org/link/BAPS.2014.DAMOP.Q1.37
Quintanilla, S. J. (2013). Deep minimim in the Coulomb-Born TDCS for inner-shell ionization of carbon by electron impact. http://meetings.aps.org/link/BAPS.2013.GEC.HW1.19
Quintanilla, S. J. (2013). Positron Collisions from Simple Atoms and Positronium-Hydrogen Collisions. http://meetings.aps.org/link/BAPS.2013.GEC.KW5.1
Quintanilla, S. J. (2013). Variational Calculations of Low-Energy Elastic Ps-H Scattering. http://meetings.aps.org/link/BAPS.2013.DAMOP.Q1.122
Quintanilla, S. J. (2012). Low-energy S- and P-wave Positronium-Hydrogen Collisions.
Quintanilla, S. J. (2011). Hyperspherical hidden crossing calculation of Ps formation in low-energy e^+-Na collisions.
Quintanilla, S. J. (2011). Low-Energy S-Wave Positronium-Hydrogen Collisions.
Quintanilla, S. J. (2011). Vortices in Coulomb-Born calculations for inner-shell ionization of carbon by electron-impact.
Quintanilla, S. J. (2010). Binding Energy and Geometry of e^+Na.
Quintanilla, S. J. (2010). The Binding Energy of PsH.
Quintanilla, S. J. (2009). Binding Energy Calculations for e^+Li and e^+Na.
Quintanilla, S. J. (1997). "The Hidden Crossing Method Applied toPositroniumFormation".
Quintanilla, S. J. (1993). "RecentDevelopmentsinthe TheoryofPositron-Hydrogen Collisions".
Quintanilla, S. J. (1990). "Positron-AlkaliAtom Scattering".
Quintanilla, S. J. (1990). "Resonances inPositron-Alkali Close-Coupling Calculations".
Quintanilla, S. J. (1990). "Theoretical Calculations of Positron Collisions with Atoms".
Quintanilla, S. J. (1986). "The ScatteringofLow-Energy ElectronsbyPositronium".
Journal Article
Alrowaily, A. W., Ward, S. J., Van Reeth, P. (2019). Deep minima and vortices for positronium formation in low-energy positron-hydrogen collisions. Journal of Physics B: Atomic, Molecular and Optical Physics. 52, 205201 (11pp). Bristol: Institute of Physics.
Van Reeth, P., Woods, D., Ward, S. J., Humberston, J. W. (2016). Corrigendum: Comparison of positronium, positron and electron scattering. Journal of Physics B: Atomic, Molecular and Optical Physics. 49, 169501 (1pp).
Van Reeth, P., Woods, D., Ward, S. J., Humberston, J. W., (2016). Comparison of positronium, positron and electron collisions with hydrogen at low velocities. Journal of Physics B: Atomic, Molecular and Optical Physics. 49, 114001.
Woods, D., Ward, S. J., Van Reeth, P. (2015). Detailed investigation of low-energy positronium-hydrogen scattering. Physical Review A. 92, 022713-1 -- 022713-17. http://journals.aps.prg/pra
Ward, S. J., Macek, J. H., (2014). Effect of a vortex in the triply differential cross section for electron impact K-shell ionization of carbon. 90, 062709. http://journals.aps.org/pra/
Quintanilla, S. J. (2010). Binding Energy and Structure of e^+Na,.
Quintanilla, S. J. (2009). "Absolute Cross Section for Positron-Impact Ionization of Hydrogen Near Threshold".
Quintanilla, S. J. (2008). "Near-ThresholdPositron Impact Ionization of Hydrogen".
Quintanilla, S. J. (2007). "Optimizing the Paths for Including the Correction Term to the Hyperspherical Hidden Crossing Method: Application to Formationine+ -Li Collisions".
Quintanilla, S. J. (2007). "The Photodetachmentof Ps− and Low-Energye+ -H Collisions".
Quintanilla, S. J. (2006). "Binding Energy and Structure of e+ Li and e− Li using a Parametric Model Potential".
Quintanilla, S. J. (2005). "PositroniumFormation Cross Section forPositron-Lithium Collisions".
Quintanilla, S. J. (2004). "E ff ect of the Core Polarization Term on Ps Formation in Low-Energy e+ -Li Collisions".
Quintanilla, S. J. (2004). "E ff ectofPolarizationon Photodetachment Thresholds".
Quintanilla, S. J. (2003). "ApplicationoftheHyperspherical Hidden Crossing MethodtoPositron-Lithium Collisions".
Quintanilla, S. J. (2002). "Positronium Formation in Low-Energy Positron Collisions with One-and Two-Electron Atoms".
Quintanilla, S. J. (2002). "The E ff ect of thePolarizationPotential on Low-EnergyAtomic Processes".
Quintanilla, S. J. (2000). "E ff ective Range Analysis of Positron-Hydrogen Collisions".
Quintanilla, S. J. (1999). "Applicationof the Hidden Crossing Method to Positronium Formation".
Other
Ward, S. J., Alrowaily, A. W., Reeth, P. V., (2018). Vortices for Ps formation in positron-hydrogen collisions Acceptance in the Ore Gap. Bulletin of the American Physical Society. 63(No. 5), T01 31 pg 189. American Physical Society. http://meetings.aps.org/Meeting/DAMOP18/Session/T01.31
Ward, S., Kent, J. B. (2017). Deep minimum in the Coulomb-Born TDCS for electron-impact ionization of atomic hydrogen. Bulletin of the American Physical Society. 62(Issue Number 10), 28 (GT1 1). http://meetings.aps.org/Meeting/GEC17/Session/GT1.1
Ward, S. J., Van Reeth, P., Alrowaily, A. W. (2017). Vortices for Ps formation in positron-hydrogen collisions. Bulletin of the American Physical Society. 62(Issue Number 8), 137 (K1 148). American Physical Society. http://meetings.aps.org/Meeting/DAMOP17/Session/K1.148
Popular Press Article
Quintanilla, S. J. (2008). "Absolute Cross Section forPositron Impact Ionization of Hydrogen Near Threshold".
Quintanilla, S. J. (2007). "Near ThresholdPositron Impact Ionization of Hydrogen".
Quintanilla, S. J. (2003). "The Application of the Hyperspherical Hidden Crossing Method toPositroniumFormation inPositron-Lithium Scattering".
Quintanilla, S. J. (2002). "Hyperspherical Hidden Crossing CalculationofPositron-Lithium Collisions".
Quintanilla, S. J. (2002). "Photodetachment of Alkali Negative Ions".
Quintanilla, S. J. (2001). "E ff ective Range Theory Analysis ofPositron-Helium Collisions".
Quintanilla, S. J. (2000). "Virtual State of thePositronium-Proton System".
Quintanilla, S. J. (1999). "Analysis of Positron-Hydrogen Collisions using an E ff ective Range Theory".
Quintanilla, S. J. (1998). "Hidden Crossing Method AppliedtoPositroniumFormation".
Quintanilla, S. J. (1998). "Hidden Crossing Theory Applied to Ps-formation inPositron-Hydrogen Collisions".
Quintanilla, S. J. (1997). "Anti-Capture to the Continuum via a Double Collision Mechanism in (e,2e) Collisions".
Quintanilla, S. J. (1997). "The Hidden Crossing Method Applied toPositroniumFormation".
Quintanilla, S. J. (1996). "The Hidden Crossing Method Applied to Positronium Formation".
Quintanilla, S. J. (1995). "Recent Developmentin the TheoryofFastPositron-Atom Collisions".
Quintanilla, S. J. (1994). "PositroniumFormationbyElectronic Capture from Hydrogenic Ions".
Quintanilla, S. J. (1994). "Single and Double Photoionizationof Helium".
Quintanilla, S. J. (1994). "WaveFunctionsforContinuum Statesof ChargedFragments".
Quintanilla, S. J. (1991). "A Variational Principle for Time-Dependent Interactions".
Quintanilla, S. J. (1989). "Close-Coupling ApproachtoPositron Scattering for Lithium, Sodium andPotassium".
Quintanilla, S. J. (1989). "Close-Coupling CalculationsofLow-EnergyPositron-Alkali Collisions".
Quintanilla, S. J. (1989). "ResonancesinLow-EnergyPositron ScatteringfromLi,NaandK".
Quintanilla, S. J. (1988). "Close-coupling ApproachtoPositron Scattering fromPotassium".
Quintanilla, S. J. (1988). "Theoretical StudiesofLow-EnergyPositron-AlkaliAtom Scattering".
Quintanilla, S. J. (1987). "Elastic Scattering of Electrons (or Positrons) from Positronium and the Photodetachment of the Positronium Negative Ion".
Quintanilla, S. J. (1986). "The Photodetachment of the Negative Ion ofPositronium (Ps−)".
Quintanilla, S. J. (1985). "The ScatteringofLow-Energy S-Wave ElectronsbyPositronium".

Presentations Given

Colloquium

Quintanilla, S. (Presenter), Vortices in atomic collisions [Presenter in Colloquium: S. J. Ward Quintanilla], Department of Physics, University of Texas at Arlington, United States of America. (20182018).

Ward Quintanilla, S. J. (Author & Presenter), Colloquium, Vortices in atomic collisions, Physics and Astronomy, Texas A&M University Commerce, Physics and Astronomy, Texas A&M University Commerce, United States of America. (20172017).

Invited Talk

Ward, S. J. (Author & Presenter), 72nd Annual Gaseous Electronics Conference, Vortices for positron ionization and positronium formation, College Station, Texas, United States of America. (20192019).

Ward, S. J. (Author & Presenter), Alrowaily, A. W. (Author), Van Reeth, P. (Author), 18th International Conference on Positron Annihilation (ICPA 18), "Vortices in Atomic Collisions", ``Ring Vortices for Positronium Formation in e$^+$-H Collisions", Orlando, USA, United States of America. (20182018).

Poster

Medrano, G. (Author), Ward, S. J. (Author & Presenter), Van Reeth, P. (Author), XX International Workshop on Low-Energy Positron and Positronium Physics, Calculations of the Ps_2 Bound-State, Belgrade, Serbia, Serbia. (20192019).

Alrowaily, A. W. (Author), Ward, S. J. (Author & Presenter), Van Reeth, P. (Author), XX International Workshop on Low-Energy Positron and Positronium Physics, Deep Minima and Vortices for Positronium Formation in Positron-Hydrogen Collisions, Belgrade, Serbia, Serbia. (20192019).

DeMars, C. M. (Author), Ward, S. J. (Author & Presenter), XX International Workshop on Low-Energy Positron and Positronium Physics, Deep Minima in the TDCS for Positron-Helium Ionization Computed Using the Coulomb-Born Approximation, Belgrade, Serbia, Serbia. (20192019).

DeMars, C. M. (Author & Presenter), Kent, J. B. (Author), Ward, S. J. (Author & Presenter), 50th Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics APS Meeting DAMOP, Deep minimum in the Coulomb-Born TDCS for e$^-$-He and e$^+$-He ionization, Milwaukee, WI., USA, United States of America. (20192019).

Ward, S. J. (Author & Presenter), Alrowaily, A. W. (Author & Presenter), Van Reeth, P. (Author), 50th Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics APS Meeting DAMOP, Multichannel Effective Range Theory Analysis of Zeros in the Positronium formation Scattering Amplitude for Positron-Hydrogen Collisions, Milwaukee, WI, USA, United States of America. (20192019).

Medrano, G. J. (Author & Presenter), Ward, S. J. (Author & Presenter), Van Reeth, P. J. (Author), 50th Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics APS Meeting DAMOP, Variational Calculations of the Ps-Ps System, Milwaukee, WI., United States of America. (20192019).

Medrano, G. (Author & Presenter), Ward, S. J. (Author & Presenter), Van Reeth, P. (Author), 25th International Conference on the Application of Accelerators in Research and Industry (CAARI 2018), Variational Calculations for the Ps-Ps System, Gaylord Texan Resort in Grapevine, Texas USA, United States of America. (20182018).

Ward, S. J. (Author & Presenter), Alrowaily, A. W. (Author & Presenter), Reeth, P. V. (Author), 49th Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics APS Meeting, Vortices for Ps formation in positron-hydrogen collisions in the Ore gap, American Physics Society, Ft. Lauderdale, FL, United States of America. (20182018).

Ward, S. J. (Author & Presenter), Alrowaily, A. W. (Author), Van Reeth, P. (Author), 71st Annual Gaseous Electronic Conference (GEC) Meeting of the American Physical Society, (Co-Located with the 60th Annual meeting of the APS Division of Plasma Physics), Ring Vortices for Positronium formation in Positron-Hydrogen Collisions in the Ore Gap, Oregon Convention Center, Portland, Oregon, United States of America. (20182018).

Ward, S. J. (Author & Presenter), Van Reeth, P. (Author), Alrowaily, A. W. (Author), 48th Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics, Vortices for Ps formation in positron-hydrogen collisions, APS, Sacramento, California, United States of America. (20172017).

Ward, S. J. (Author & Presenter), Kent, J. B. (Author), 70th Annual Gaseous Electronics Conference, Nov. 6-10, 2017, Pennsylvania, Pittsburg, United States of America. (20172017).

Van Reeth, P. (Author & Presenter), Alrowaily, A. W. (Author), Ward, S. J. (Author), Hiley, B. J. (Author), EmQM17 Emergent Quantum Mechanics, Vortices in low-energy positron-hydrogen collisions, University of London, United Kingdom. (20172017).

Kent, J. B. (Author & Presenter), Ward Quintanilla, S. J. (Author), Physics department Senior Thesis undergraduate student poster presentations, Vortex for Hydrogen ionization by Electron Impact, Physics Department, UNT, Physics Department, UNT, United States of America. (2017).

Seminar

Ward, S. (Presenter), Vortices in atomic collisions [Presentator: S. J. Ward Quintanilla], AMOPP (Atomic, Molecular, Optical and Positron Physics) group, Department of Physics and Astronomy, University College London, London, England, UK, United Kingdom. (20182018).

Contracts, Grants and Sponsored Research

Grant - Research
Ward (Quintanilla), S. J. (Principal), "Theoretical Investigation of Low-Energy Positron and Positronium Collisions," Sponsored by National Science Foundation, Federal, $90992 Funded. (September 01, 2017August 31, 2020).
Ward Quintanilla, S., "Positronium-positronium scattering," Sponsored by Physics Department, University of North Texas, University of North Texas, $3469.02 Funded. (20172017).
Uncategorized
Quintanilla, S. J. (Principal), "Positron and Positronium Collisions with Simple Atoms," Sponsored by National Science Foundation, $164516. (20102014).
Quintanilla, S. J. (Principal), "Collaborative research: Hyperspherical hidden crossing method applied to positron-alkali," Sponsored by National Scienec Foundation, $151590. (20042008).
Quintanilla, S. J. (Co-Principal), "Application of the Hyperspherical Hidden Crossing Method to Low-Energy Positron Collisions with the Alkali and Hydrogen Atoms," Sponsored by Faculty Research Grant, $1500. (20032004).
Quintanilla, S. J. (Co-Principal), "Low-Energy and Near-Threshold Positron Collisions," Sponsored by Faculty Research Grant, $4500. (20022003).
Quintanilla, S. J. (Co-Principal), "Near-Threshold Photodetachment," Sponsored by Faculty Research Grant, $750. (20022002).
Quintanilla, S. J. (Co-Principal), "Near-Threshold Behavior of Atomic Processes," Sponsored by Faculty Research Grant, $4000. (20012002).
Quintanilla, S. J. (Co-Principal), "Low-Energy Positron Collisions," Sponsored by Faculty Research Grant, $5000. (20002001).
Quintanilla, S. J. (Co-Principal), "Probing the three-body," Sponsored by National PI: S. J. Ward, $60000. (19982000).
Quintanilla, S. J. (Co-Principal), "Probing the Three-Body Coulomb system via Positronium Formation in Positron-Hydrogen Collisions," Sponsored by Faculty Research Grant, $3500. (19981999).
Quintanilla, S. J. (Co-Principal), "Low-Energy Positron-Hydrogen Ionization," Sponsored by Faculty Research Grant, $5000. (19971998).
Quintanilla, S. J. (Co-Principal), "Positronium Formation—A Three Body Coulomb Problem," Sponsored by Faculty Research Grant, $3800. (19961997).
Quintanilla, S. J. (Co-Principal), "Positronium Formation at Low and High Energies," Sponsored by Faculty Research Grant, $2500. (19951996).
Quintanilla, S. J. (Co-Principal), "Single and Double Photoionization of Helium," Sponsored by Faculty Research Grant, $2700. (19941995).
Quintanilla, S. J. (Co-Principal), "Positron ionization," Sponsored by National PI:S.J. Ward, $66000. (19921995).
Quintanilla, S. J. (Co-Principal), "Theoretical Study of Electron-Impact Ionization," Sponsored by Faculty Research Grant, $2500. (19931994).
Quintanilla, S. J. (Other), "JuniorFacultyResearchGrant," Sponsored by Faculty Research Grant. (19911992).
Quintanilla, S. J. (Co-Principal), "Positron Impact Ionization and Positronium Formation at High Energies," Sponsored by Faculty Research Grant, $3000. (19911992).

Service

University Service

Other, Ah-hoc for Physics Ph.D. Qualifer Exam. (20202020).

Committee Member, Search Committee for Astrophysicist. (20192020).

Member, Graduate Committee. (20152019).

Member, Departmental Doctoral Committee. (20152015).

Member, Undergraduate Committee. (20142015).

Member, Departmental Doctoral Committee. (20142014).

Other, Departmental Doctoral Examination Committee. (20092013).

Other, Departmental Personnel Committee. (20102012).

Other, Affiliated to the Search Committee for Materials Modeling Research Cluster. (20102011).

Member, Search committee for senior hire in Ion Beam Accelerator Laboratory. (20102011).

Member, High-Performance Computing Advisory Committee. (20092010).

Member, Hign-Performance Computing Committee. (20082009).

Other, Search Committee for Condensed Matter Theorist. (20082009).

Committee Chair, Grievance Committee. (20082008).

Other, High-Performance Computing Committee. (20082008).

Other, Undergraduate Committee. (20042006).

Other, Doctoral Examination Committee. (20032004).

Other, Personnel Committee. (20032004).

Committee Chair, Doctoral Examination Committee. (20022003).

Other, Graduate Committee. (20012002).

Other, Revision of Physics Charter Committee. (20012002).

Other, Search Committee. (20002002).

Committee Chair, Personnel Committee. (19992001).

Other, Executive Committee. (19971998).

Other, Search Committee. (19971998).

Committee Chair, Graduate Committee. (19951998).

Other, Fall Colloquium Coordinator. (19971997).

Other, Search Committee. (19961997).

Other, Departmental Examination Committee. (19931997).

Other, Election Judge. (19941995).

Other, Rhodes/Marshall Faculty Screening Committee. (19941995).

Other, Assistant Election Judge. (19931994).

Other, Computational Physics Laboratory Committee. (19921994).

Other, Physical Facilities Committee. (19911993).

Professional Service

Reviewer, Journal Article, European Physical Journal D. Insitute of Physics.. (2017 – Present).

Reviewer, Journal Article, Journal of Physics B. Insitute of Physics.. (2017 – Present).

Reviewer, Grant Proposal, National Science Foundation. (2017 – Present).

Reviewer, Journal Article, Physical Review A. American Physical Society. (2017 – Present).

Chairperson, GEC, College Station, Texas. (October 30, 2019October 30, 2019).

Committee Member, GEC, College Station, Texas. (October 29, 2019October 30, 2019).

Other, University of North Texas, Denton, TX. (20172018).

Reviewer, Journal Article, Nature Communications. (20172017).

Other, University. (20172017).

Other, Invited Dr. Doerte Blume to give colloquium, Denton, Texas. (November 28, 2017November 28, 2017).

Session Chair, 70th Annual Gaseous Electronics Conference, Pittsburgh, Pennsyvania. (November 9, 2017November 9, 2017).

Member, International advisory committee for the XIV international workshop on ``Low Energy Positron and Positronium Physics. (20112011).

Other, Member of the Executive Committee of the Few-Body Topical Group of the American Physical Society (APS). (20082011).

Member, International advisory committee for the XIV international workshop on ``Low Energy Positron and Positronium Physics". (20092009).

Other, International advisory committee for the XV international workshop on"Low Energy Positron and Positronium Physics",York University, Toronto. (20092009).

Other, International advisory committee for the XIV international workshop on"Low Energy Positron and Positronium Physics", Reading University. (20072007).

Other, Assistant Election Judge. (20042006).

Other, International advisory committee for the XIII international workshop on"Low Energy Positron and Positronium Physics", Campinas, SP. (20052005).

Other, International advisory committee for the XII international workshop on"Positron and Positronium Physics", Sandberg. (20032003).

Other, The XXI International Workshop "Positron and Positronium Physics", Sandberg. (20032003).

Other, International advisory committee for the XI international workshop on "Low Energy Positron and Positronium Physics", Santa Fe, New Mexico. (20012001).

Other, For the session"Positron and Positronium on Atoms" at the workshop "Positron and Positronium Interactions: New Directions", ITAMP. (20002000).

Other, International advisory committee for the workshop on Low-Energy Positron and Positronium Physics Satellite Meeting to XXI ICPEAC, Sendai. (19991999).

Other, Annual Meeting of the Texas Section of the American Physical Society. (19911991).

Public Service

Other, Denton Calvary Academy, Denton, Texas. (November 2019November 2019).

Other, Woodrow Wilson Elementary School, Denton, Texas. (20142015).

Other, Woodrow Wilson Elementary School, Denton. (20132014).