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Research in Physics

RESEARCH ACTIVITIES IN THE DEPARTMENT OF PHYSICS

The Department of Physics has active and vibrant research program in Experimental Nuclear Physics, Computational Physics, and Atmospheric Sciences (Atmospheric Physics, Climate and Weather modeling). The researchers and their areas of research are provided below in alphabetical order

  Abdellah Ahmidouch

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Current Research focus:  Investigations in Intermediate Energy Physics.  This includes the following activities at Jefferson Lab

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  • The nucleon Form Factors (FF) program, Experiments E12-09-16, E12-09-19, dedicated to the measurement of the neutron electromagnetic form factor ratio GEn/GMn in double polarized, quasi-elastic 3He(e,e’n)pp scattering at momentum transfers Q2 of 5-10.2 (GeV/c)2, and the neutron to the proton magnetic form factor ratio GMn/GMp in quasi-elastic scattering off the deuteron at Q2 up to 18 (GeV/c)2.
  • The Møller experiment E12-09-05, which measures the parity-violating asymmetry APV in the scattering of longitudinally polarized 11 GeV electrons off the atomic electrons in a liquid hydrogen target (Møller scattering),
  • The Hall C, GEn Collaboration (E12-11-009) which proposes to extend previous measurements of GEn from deuterium and through recoil polarimetery to Q2 =6.88 (GeV/c)2
  • Construction of the Quartz Hodoscope for the trigger system of the Hall-C super HMS spectrometer, a crucial component for the Jefferson Lab 12 GeV physics program in Hall C.
  • Jefferson Lab Hall-C SANE experiment. The experiment is dedicated to study the spin structure of the proton. The experiment is in the data analysis phase.
  • Other research interests include: (1) Development of nuclear and particle physics instrumentation (2) Medical Physics: Imaging, Application and exploration of nuclear physics potential in medicine. (3) Nuclear Power (4) Physics Education

SOME RELEVENT PUBLICATIONS  

  1. Polarization components in p0 photoproduction at photon energies up to 5.6 GeV, W. Luo et al., Phys. Rev. Lett., 108, 222004 (2012)
  2. A New Measurement of the p0 Radiative Decay Width”, I. Larin et al., Phys. Rev. Lett., Vol.106, No.16, 2011
  3. Recoil Polarization Measurements of the Proton Electromagnetic Form Factor Ratio to Q^2 = 8.5 GeV2, A.J.R. Puckett et al. JLAB-PHY-10-1155, May 2010. (Published Jun 18, 2010). 12pp.
    Published in Phys. Rev. Lett.104:242301, 2010.
  4. Applications of quark-hadron duality in F(2) structure function, S.P. Malace et al., JLAB-PHY-09-944, May 2009. (Published Sep 2009). 33pp. Published in Phys. Rev. C80:035207, 2009.
  5. Probing Quark-Gluon Interactions with Transverse Polarized Scattering. K. Slifer et al.. JLAB-PHY-08-893, Dec 2008. (Published Sep 3, 2010). 5pp. Published in Phys. Rev. Lett.105:101601, 2010.
  6. Electroproduction of Eta Mesons in the S(11)(1535) Resonance Region at High Momentum Transfer.
    M.M. Dalton et al. JLAB-PHY-08-817, Apr 2008. 30pp. Phys. Rev.C80:015205, 2009.
  7. Neutral Pion Electroproduction in the Resonance Region at High Q2. A.N. Villano et al. JLAB-PHY-09-996, Jun 2009. 40pp. Published in Phys.Rev.C80:035203, 2009.
  8. Proton spin structure in the resonance region, F.R. Wesselmann et al., Phys. Rev. Lett. 98:132003, 2007
  9. Proton GE/GM from Beam-Target Asymmetry, M. K. Jones, et al., Phys. Rev. C74:035201, 2006.
  10. The ratio of proton electromagnetic form factors via recoil polarimetry at Q2=1.13 GeV/c)2”, G. McLachlan, …, A. Ahmidouch, … et al., Nucl. Phys. A764:261-273, 2006.
  11. Measurements of The Neutron Electric to Magnetic Form-Factor Ratio GEn/GMn from the 2H(e,e'n)1H Reaction to Q2=1.45 (GeV/c)2, B. Plaster et al., Phys.Rev.C73:025205, 2006.

Opportunities for students:- Funding availability, source etc.

Research scholarships are available for qualified students, both graduate and undergraduate.

Research Assistant positions available

Collaborators-

The Jefferson Lab Moller collaboration, the Jefferson Lab SANE collaboration, Jefferson Lab – Hall C, NC State University, Hampton University, Argonne National Lab, Rutgers University, Florida International University, Kent State University, Norfolk State University, Old Dominion University, CEA Saclay (France), LNS Saclay (France), IPNO Orsay (France), ISN Grenoble (France), etc …

Dr. Solomon Bililign

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Research Group Members:

Research focus: Atmospheric Physics and Chemistry- Characterizing organic and inorganic acids and aerosols in the atmosphere emitted as a result of biomass burning and the study their impact on climate. Specific topics include:

  • Negative Ion proton transfer mass spectrometry to Measure: a) Acidities of gas-phase acids; b) Rate of H-transfer; c) Water cluster characterization. The goal is to get estimates of the free energy of hydration of carboxylate ions, and determination of their effective gas phase acidity

The relative gas-phase acidities of the simple carboxylic acids (propionic, butyric and others) and some isotopomers of acetate play a central role in VOC chemistry and in an understanding of climate forcing.    This project addresses critical problems in air quality and climate change, because organic acids (carboxylic acids) are key to the chemistry of volatile organic compounds (VOCs). VOCs are in turn are related to the formation of ozone and organic aerosols which have a significant impact on regional air quality.

  • Investigate vibrational overtone initiated photodissociation processes that are significant sources of atmospheric radicals using cavity ring-down spectroscopy. The vibrational O-H overtone absorption cross sections of carboxylic acids and other OH-containing species are necessary quantities to calculate the photochemical reaction rate constant (J) for reactions initiated by the excitation of the O-H overtone.

The inability to account for the quantity of OH radical observed in the atmosphere has recently prompted an investigation into absorption of visible and near infrared wavelengths that leads to direct overtone photolysis.  While there has been laser induced fluorescence (LIF) and action spectroscopy studies, the overtone spectroscopy has not been studied using CRD, which is a superior technique for directly measuring the absorption.  Candidates for this work are organic acids emitted through Biomass burning. Acetic acid and peracetic acid have been studied.

  • Measurement of optical properties of biomass aerosols (Black Carbon) using cavity ring down spectroscopy

According to the IPCC’s Fourth Assessment Report (2007), our ability to quantify the direct effect of aerosols on the global climate is hindered by uncertainties in the measurements of aerosol extinction. Aerosols that scatter and absorb radiation can have a cooling or warming effect depending on the magnitude of their absorption term and the albedo of the underlying surface. Irrespective of whether cooling or warming occurs, the magnitude of the effect is directly related to the quantity of light an aerosol absorbs. Aerosol absorption contributes to the aerosol single scatter albedo (SSA) and aerosol optical depth, which is the vertical integration of aerosol extinction. Optical properties of aerosols produced by biomass burning are important because of the global impact of these aerosols as well as the wide range of radiative effects, i.e., atmospheric warming or cooling. Obtaining a better estimation of their optical properties promotes a better understanding of climate forcing caused by aerosols. A better understanding of the climate forcing due to biomass burning will help global climate models better predict future trends in global temperature.

  • Measurement of the Henry's law coefficient and first order loss rate of Isocyanic Acid in the liquid phase

Isocyanic acid is a product of biomass burning, some diesel engines, cigarettes, and other sources. We have studied its fate in the atmosphere, and determined that the only major removal process is by dissolving into cloud water and subsequent pH-dependant reactions in the aqueous phase. We aim to measure the rate of these reactions as a function of pH and expand it to other systems and reactions. Reactions with other species in solution can be indicative of oligomerization reactions that give rise to secondary organic aerosol, other species can be indicative of reactions with biomolecules and human health effects can be inferred, partitioning into other media can be studied to determine how rapidly isocyanic acid partitions into organic aerosols or biological systems, etc. This methodology is also not limited to isocyanic acid, and can be applied to a variety of systems. This research project will likely incorporate resources available at the Joint School of Nanoscience and Nanoengineering.

aerosol equipmentcavity ring

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Other Current Research Interests:

Geosciences education, photophysics, chemical reaction dynamics, nanoclusters

 MOST RECENT PUBLICATIONS

 S. Bililign, Y.-L. Lin, R. Davis, S. Ilias, L. Kurkalova, Y. Kyei, Y. Rastigeyev and G.  Uzochukwu, “Effects of Global Warming on North Carolina,” International Journal of Climate Change Impacts and Responses, 2011, Vol. 3 Issue 2, 53-70

Israel Begashaw, Marc N. Fiddler, Solomon Bililign, Steven Brown,, “Measurement of the fourth O-H overtone absorption cross section in acetic acid using cavity ring-down spectroscopy” The Journal of Physical Chemistry A, 2011, 115, 753-761

Marc M. Fiddler; Israel Begashaw ;  Matthew A. Mickens; Michael S. Collingwood Zerihun Assefa,  and Solomon Bililign, “Laser Spectroscopy for Atmospheric and Environmental Sensing,” Sensors. 2009, 9, 10447-10512.

Natenael Semmineh1 and Solomon Bililign, Denis Hagebaum-Reignier and Gwang-Hi Jeung “Experimental Studies of Collisions of excited Li (4P) atoms with C2H4, C2H6, C3H8, and Theoretical interpretation of the Li-C2H4 System.”  Chemical Physics 355 (2009) 157–163,

Kevin Weddburn, Mel Levy, Solomon Bililign, Robert Gdanitz, “"Geometries and stabilities of 3d-transition metal-cation benzene complexes, M+Bzn (M = Sc-Cu, n = 1, 2)",”Chem. Phys. 326, 600 (2006)

Komaragiri, Vivek; McCarter, Benjamin; Bililign, Solomon; Hagebaum-Reignier, Denis; Ledentu, Vincent; Jeung, Gwang-Hi Jeung, “Experimental and Theoretical Studies of the Quenching of Li (3p, 4p) by N2,Journal of Chemical Physics, 123, 24303 (2005).

  Current Active Collaborations:

  • Addis Ababa University: Ethiopia; 2004-present: geosciences, atmospheric sciences, and statistical physics.
  • PENN STATE, (Andy Nyblade) University of the Witwatersrand, South Africa: Partnership for international research and education program in geosciences. 2004-present. http://pire.africaarray.psu.edu/
  • NOAA –ISET Center Partner (Subcontract) Minority Serving Institutions: Cathy Cooner- University of Alaska Southeast (UAS); Alam Hason-California State University-Fresno (CSU-Fresno); Samir-Ahmed- City University of New York (CUNY), Lei-Qian-Fisk University (FU); Fred Semazzi- North Carolina State University (NCSU); Vipin Kumar-University of Minnesota (UM) (www.noaaiset.org)
  • NCAR-Atmospheric Chemistry Division: Geoff Tyndall; John Orlando, Mary Barth
  • NOAA-ESRL- Atmospheric Chemistry Division: Jim Roberts, Steve Brown, Ranajit Talukdar

 Opportunities for Students: Research Assistantship and Tuition support for Graduate students and Stipends for Undergraduate Students are available.

Dr. Samuel Danagoulian

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Current Research focus:

The research is mainly associated with scientific program at the Thomas Jefferson National Accelerator Facility (Jefferson Laboratory or JLAB, Newport News, VA).

Spin Asymmetries on the Nucleon Experiment (SANE, JLAB experiment E07-003)

  • A Precise Measurement of the Neutral Pi-meson Lifetime at Jefferson Laboratory (PrimEx, JLAB experiments E-02-103, E-08-023)
  • Neutron Electromagnetic Form Factor Measurement using 8.8 GeV and 6.6 GeV Beam Energies and BigBite Spectrometer in Hall A (E12-06-121)
  • Ultra precise measurement of the weak mixing angle by measuring the parity-violating asymmetry APV in Moller Scattering (the Moller Experiment E12-09-05)
  • Investigation of photodisintegration of deuterium at low energy for the purpose of cancer treatment.

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Recent Publications:

Observation of the 7He hypernucleus by the (e, e’K+) reaction. … A. Ahmidouch, … S. Danagoulian,…A. Gasparian et.al. HKS (JLab E01-011) Collaboration. Submitted to the PRL 2012

Polarization Components in π0 Photoproduction at Photon Energies up to 5.6 GeV. …A. Ahmidouch, … S. Danagoulian, et.al. SANE Collaboration. Phys. Rev. Lett. 108, 222004 (2012)

Semi-inclusive charged-pion electroproduction off protons and deuterons: Cross sections, ratios, and access to the quark-parton model at low energies. …A. Ahmidouch, … S. Danagoulian, et.al. Phys. Rev. C 85, 015202 (2012)

New Measurement of the π0 Radiative Decay Width.  … A. Ahmidouch, …S.Danagoulian, …A. Gasparian (PRIMEX Collaboration). Phys. Rev. Lett. 106, 162303 (2011)

Recoil Polarization Measurements of the Proton Electromagnetic Form Factor Ratio to Q2 = 8.5 GeV^2. …A. Ahmidouch, … S. Danagoulian, et.al.SANE Collaboration.  Phys.Rev.Lett.104:242301, 2010

“Hypernuclear spectroscopy at JLab Hall C”. … A. Ahmidouch, …S.Danagoulian, …A. Gasparian , et.al.HKS (JLab E01-011) Collaboration,  Nucl.Phys.A835:121-128,2010.

Neutral pion electroproduction in the resonance region at highQ2. … A. Ahmidouch,… S. Danagoulian, et.al. Phys.Rev.C80:035203,2009

Student Opportunities

NSF funding available for students

Collaborators-

UMas, MIT, ANL, UVA, Duke U., FIU, UMD, YerPI (Armenia), Tohoku U. (Japan), KEK (Japan) etc.

Dr. Ashot Gasparian

  • “Photoproduction of Pseudoscalar Mesons off Nuclei at Forward Angles”, S. Gevorkyan, A. Gasparian, L. Gan, I Larin, M. Khandaker Published in: Phys. Rev. C80, (2009), 055201.
  • Photoproduction of p+p -  meson pairs on the proton”, M. Battaglieri, et al. Published in: Phys. Rev.  D8, (2009), 072005.
  • “Neutral Pion Electroproduction in the Resonance Region at High Q2”, A.N. Villano, et al. Published in: Phys. Rev.  C80, (2009),035203.
  • “Hypernuclear spectroscopy at JLab Hall C”, O. Hashimoto, et al. Published in: Nucl.Phys. A835:121-128, 2010.
  • “Incoherent Photoproduction of Pseudoscalar Mesons off Nuclei at Forward Angles”, S. Gevorkyan, A. Gasparian, L. Gan, I. Larin, M. Khandaker Published in: hep-ph arXiv: 0908.1297, submitted to Phys. Rev. C, in 2010.

Dr. Ken Flurchick

Research Group Members:

Variable Star Systems:  B,Griego - Physics MS Student

Energetic Solids  A. Crite - CSEPhD Student

Current Research focus:  

Variable Star Systems

Utilizing the availability of powerful simple-to-use CCD cameras, synchronization electronics for tracking stars and to connect longitudinally distinct telescopes and small (around 10 to 14 inch reflecting) telescopes, the Global Network of Astronomical Telescopes (GNAT) has completed several full sky surveys. The data pipeline to reduce the photometry data and to analyze the data to find and classify variable stars is an enormous task.

In conjunction with GNAT-MOTESS (Collaboration to conduct a variable star survey which is a deep, wide-field variability survey conducted over several years with a total sky coverage of 300 square degrees. GNAT: is the Global Network of Astronomical Telescopes is a non-profit foundation. MOTESS-Moving Object and Transient Event Search System) .The research here is to analyze the luminosity data from the stellar images in the sky survey.  The data analysis includes the identification of spurious data in the image, duplicate data due to overlapping image frames and other bad data in the luminosity data.

These research activities are divided into these major topics:

  • Stellar Image Data Pipeline: Generation of the luminosity data for the catalogs and the clean-up of MG catalogs. This work is performed in close collaboration with the GNAT team. Several new statistical methods have been developed to analyze the light curves (LC)for spurious data. These methods are being applied to the new catalog data.  Also, other work focuses on generating the instrumental photometry data, using the existing data pipeline.
  • Mining the Catalogs: Using the catalogs to identify variable stars and candidate eclipsing systems.
  • Eclipsing Star Systems:  Using the catalog data plus follow-on observations to identify (and model) the eclipsing star system candidates.
  • Astronomy Education using the Dynamic Web : This work is in collaboration with Dr. R. Culver at Colorado State University to use the capabilities of the dynamic web to introduce astronomical concepts.

Energetic Solids

Energetic Solids are a class of molecular solids in which bond dissociation can rapidly occur in response to mechanical energy of a shock compression. This process is poorly understood. Current work is investigating phase changes of the solids prior to the molecular bond dissociation.

Molecular crystals possess the property that the constituents of the lattice, the molecules, bond together in the crystal without altering their intrinsic structure. The study of energetic solids and their behavior under uniform stress due to shock fronts is important. To determine electronic and structural information about these crystals is crucial. As the molecules which make up the constituents of the lattice are not significantly altered by the crystal field, calculations using the generally avaiable DFT functionals should give good results. The caveat for this approach is the level of approximation for any particular functional.

Recent Publications:

  1. W.F. Perger, S. Vutukuri,  Z.A. Dreger , Y.M. Gupta and K. M. Flurchick “First-Principles Vibrational Studies of Pentaerythritol Crystal under Hydrostatic Pressure” Chemical Physics Letters, 422, 10 May 2006, 397-401.
  2.  K.M. Flurchick, “DFT Functionals and Molecular Geometries”, Chemical Physics Letters Volume 421, 15 April 2006, 540-543.
  3. Chopade, P.; Flurchick, K.M.; Bikdash, M.; "A Novel Visualization Technique for Smart Power Grid Analytics:  Contingency, Security and Economics  Aspects", submitted for IEEE 2012 Power and Energy Conference at University of Illinois at Urbana-Champaign, Illinois, February 24 - 25, 2012.

 Collaborators-

            Dr Warren Perger, Michigan Technological University

            Dr. Eric Craine, Western Research Inc.

            Dr. Roger Culver, Colorado State University

            Dr. Lee Bartolottil, East Carolina University

Dr. Abede Kebede

  • Ratios in Higher Order Statistics (RHOS) Values of Seismograms for Improved Automatic P-Phase Arival Detection (Dugda Mulugeta and Abebe Kebede)
  • Submitted to Geoscience and Remote Sensing Letters, 2010

Dr. Yuh-Lang Lin

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PhD students] James Spinks (EES), Galen Smith (EES), Van Nguyen (CSE), Cheikna Baber (EES), Riem Rostom (EES), Patrick Pete (EES), Stephany Taylor (EES); [MS students] Jose Garcia-Rivera (Physics), Nimrod Micael  (Physics); [Physics BS students] Delonte Duff (ASME), Justin Riley (ASME), Percey Williams (ASME), Cameron Anderson (ASME); [Recent Graduates] Yi-Chih Huang (PhD-EES, 2012), Cristina Carrasco (MS-Phys), Ian Colon (MS-Phys), Van Nguyen (MS-CSE)

Current Research focus:  Research interests include: study of cloud microphysics parameterization, mesoscale dynamics and modeling (orographic rain, gravity and mountain waves, moist convection, wake vortices), severe local storms, tropical waves and cyclones, and forest fires.  Research topics include:

  • Hurricane Research (with collaborators listed): Simulations and Dynamics of
  1. African easterly waves and jets (Collaborators: Dr. G. Tang, Dr. L. Liu; EES student: J. Spinks)
  2. Effects of ocean spray, sea-surface temperature, and orography on tropical cyclone intensity (Dr. Y. Rastigejev, Physics Student: J. Garcia-Rivera, CSE student: V. Ng; ASME student: Justin)
  3. Rapid intensification of hurricanes (Physics MS graduate: C. Carrasco; Physics student: J. Garcia-Rivera)
  4. Orographic and coastal effects on landfalling hurricanes (Collaborator: Dr. L. Liu; CSE student: V. Ng, EES Students: S. Taylor, R. Rostom)

hurricane

  • Tornadoes Outbreaks
  1. Environments conducive to tornado outbreaks in 2011 and 2012 (Collaborator: Dr. L. Liu; ASME students: Delonte, Percey, Cameron)
  2. Data assimilation for severe storm initiation (EES student: C. Baber)
  3. Effects of aerosols on torndo genesis (Physics student: N. Micael)
  4. Orographic effects on tornado outbreaks (EES student: G. Smith)
  5. Hurricane-induced tornado outbreaks (EES student: P. Pete)

tornado

  • Other Research
  1. Coupling of Atmospheric & Hydrological  Models [Korea collaborators: Dr. Y. Jung, Dr. Kim]
  2. Orographic Rain Dynamics (Taiwan collaborators: Dr. C-S Chen et al.)
  3. Categorization of TCs over Madagascar Mountains (Madagascar collaborators: Rakotomavo, Dr. Raholijao)
  4. Orographic effects on MJO (Taiwan collaborators: Dr. Hsu et al.)

Recent Publications: (Please see http://mesolab.ncat.edu => publications for a complete list)

(i)  Five recent publications

Lin, Y.-L., L. Liu, G. Tang, J. Spinks, and W. Jones, 2012: Origin of pre-Debby (2006) African easterly wave and mesoscale convective system.  Meteor. Atmos. Phys., in review.

Shen, B.-W., W.-K. Tao, and Y.-L. Lin, 2012: Genesis of twin tropical cyclones as revealed by a global mesoscale model: The role of mixed Rossby gravity waves. J. Geophys. Res., in press.

Shen, B.-W., W.-K. Tao, and Y.-L. Lin, A. Laing, 2012: Genesis of twin tropical cyclones as revealed by a global mesoscale model: The role of mixed Rossby gravity waves. J. Geophys. Res., J. Geophys. Res., Vol. 117, D13114, doi:10.1029/2012JD017450.

Bililign, B., Y.-L. Lin, R. Davis, S. Ilias, L. Kurkalova, Y. Kyei, Y. Rastigeyev, G. Uzochukwu, and S, Bae, 2012: Effects of global warming on North Carolina. Int’l J. Climate Change: Impacts and Responses, Vol. 3, Issue 2, 51-70.

Chen, C.-S., Y.-L. Lin, N.-N. Hsu, C.-L. Liu, and C.-Y. Chen, 2011: Orographic effects on localized heavy rainfall events over southwestern Taiwan on 27 and 28 June 2008 during the post-Mei-Yu period. Atmos. Research, 101, 595-610.

(ii) Five representative publications

Lin, Y.-L., and L. Crosby Savage III, 2011: Effects of landfall location and the approach angle of a cyclone vortex encountering a mesoscale mountain range. J. Atmos. Sci., 68, 2095-2106.

Lin, Y.-L., 2007:  Mesoscale Dynamics.  Cambridge University Press, 630pp.

Lin, Y.-L., S.-Y. Chen, C. M. Hill, and C.-Y. Huang, 2005:  Control parameters for tropical cyclones passing over mesoscale mountains, J. Atmos. Sci., 62, 1849-1866.

Lin, Y.-L., 1990: A theory of cyclogenesis forced by diabatic heating.  Part II: A semigeostrophic approach. J. Atmos. Sci., 47, 1755-1777.

Lin, Y.-L., R. D. Farley, and H. D. Orville, 1983: Bulk parameterization of the snow field in a cloud model.  J. Clima. Appli. Meteor., 22, 1065-1092. 

Opportunities for students: Funding availability, source etc.

  1. Integrating NASA Science, Technology and Research in Undergraduate Curriculum and Training (INSTRUCT), NASA
  2. HBCU-RISE Center for Advanced Multi-scale Computational Algorithms (AMCA), NSF
  3. Impact of the NASA Reanalysis (MERRA) Data on the Predictability of Tropical Cyclone Formation and Tropical Waves, NASA (pending)
  4. IGERT in Extreme Weather and Climate Change, NSF  (pending)
  5. Battlefield Weather Prediction in Complex Terrain, DoD (pending)                                                    

Collaborators – Embedded in the description of current research focus (above)

Dr. Ronald Pedroni

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Current Research focus:  Experimental  nuclear physics;  topics include:

  • Research at the Triangle Universities Nuclear Laboratory (TUNL) located on the campus of Duke University in Durham, NC. Under a collaborative grant with Duke University from the National Science Foundation (NSF) and the Department of Homeland Security (DHS), measurements important for interpreting gamma-ray scans of cargo containers have and are being made at the Duke Free Electron Laser Laboratory (DFELL) using the High Intensity Gamma-ray Source (HIgS).  These include measurements of nuclear resonance fluorescence (NRF) cross sections and polarization asymmetries on actinides and other special nuclear materials and high-precision gamma-ray attenuation measurements in the energy range of 3 to 20 MeV.  
  • Research at the Thomas Jefferson National Accelerator Facility (JLab) located in Newport News, VA.  There are three topics for this research:  a) measurements of the lifetime of the neutral pi meson (p°) (PrimEx) in Experimental Hall B , b) measurements of the lifetime of the eta meson (η) in the new Experimental Hall D, and measurement of the charge radius of the proton.

Publications Related to the NSF/DHS Projects:

Measurement of the 241Am(n,2n) reaction cross section from 7.6 MeV to 14.5 MeV, A.P. Tonchev, C.T. Angell, M. Boswell, A.S. Crowell, B. Fallin, S. Hammond, C.R. Howell, A. Hutcheson, H.J. Karwowski, J.H. Kelley, R.S. Pedroni, W. Tornow, J.A. Becker, D. Dashdorj, J. Kenneally, R.A. Macri, M.A. Stoyer, C.Y. Wu, E. Bond, M.B. Chadwick, J. Fitzpatrick, T. Kawano, R.S. Rundberg, A. Slemmons, D.J. Vieira, and J.B. Wilhelmy, Physical Review C 77, 054610 (2008).

Cross sections for 238U(n,n'γ) and 238U(n,2nγ) reactions at incident neutron energies between 5 and 14  MeV, A. Hutcheson, C. Angell, J.A. Becker, A.S. Crowell, D. Dashdorj, B. Fallin, N. Fotiades, C.R. Howell, H.J. Karwowski, T. Kawano, J.H. Kelley, E. Kwan, R.A. Macri, R.O. Nelson, R.S. Pedroni, A.P. Tonchev and W. Tornow, Physical Review C 80, 014603 (2009).

Neutron-deuteron analyzing power data at 19.0 MeV, G.J. Weisel, W. Tornow, B.J. Crowe, III, A.S. Crowell, J.H. Esterline, C.R. Howell, J.H. Kelley, R.A. Macri, R.S. Pedroni, R.L. Walter and H. Witała, Physical Review C 81, 024003 (2010) .

Discrete deexcitations in 235U below 3 MeV from nuclear resonance fluorescence, E. Kwan, G. Rusev, A.S. Adekola, F. Dönau, S.L. Hammond, C.R. Howell, H.J. Karwowski, J.H. Kelley, R.S. Pedroni, R. Raut, A.P. Tonchev and W. Tornow, Physical Review C 83, 041601 (2011).

Nuclear Data Measurements on Actinides Using The High Intensity Gamma-Ray Source, R.S. Pedroni, A. Adekola, C.W. Arnold, S.L. Hammond, A. Harrell, C.R. Howell, H.J. Karwowski, J. Kelley, E. Kwan,          R. Raut, G. Rich, G. Rusev, D. Ticehurst, A.P. Tonchev and W. Tornow, collaboration talk presented at the 4th Annual Academic Research Initiative Grantees Conference from April 26-28, 2011 in Alexandria, VA.

Publications Related to the JLab Projects:

Nuclear targets for a precision measurement of the neutral pion radiative width, P. Martel et al., (PrimEx Coll.:  see below), Nuclear Instruments and Methods in Physics Research A612 (2009) 46.

New Measurement of the π0 Radiative Decay Width, I. Larin et al., (PrimEx Coll.:  see below), Physical Review Letters 106, 162303 (2011).

Opportunities for students:  Some funding is available for one undergraduate student and one graduate student from the NSF/DHS

Collaborators:

TUNL (NSF/DHS):  Calvin R. Howell, Michael J. Theiren and Werner Tornow.

JLab:  Ashot Gasparian, The PrimEx Collaboration, The Hall D/GlueX Collaboration and The Proton Charge Radius Collaboration.

Dr. Jing Zhang

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Group members: Fuhong Liu (Ph.D. Candidate), Adrian Santiago (M.S.Graduate), Steve Stegall (Ph.D. Candidate), Wei Tao (Ph.D. Candidate), Gian Villamil-Otero (M.S.Graduate), and Jing Zhang (Associate Professor)

Current Research focus:  

1.      High Resolution Regional Reanalysis with the WRF-Var Modeling System 

With great support from BOEM/DoI, we are conducting an environmental study for the Chukchi/Beaufort Seas with a final goal to generate 30-year high-resolution regional reanalysis with an optimized WRF-Var modeling system. Preliminary results demonstrate that high-resolution regional reanalysis outperforms most global reanalyses as shown below.

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2.      Arctic Marginal Ice Zone Wind Field Analysis

 The Arctic Marginal Ice Zone areas are experiencing substantial changes recently, such as drastic retreat of sea ice, increased storm invasion, a large fluctuation in the surface pressure pattern. In this study we are focusing the area’s wind field analysis, including wind field climatology, changes, and extremes, and its interactions with sea ice changes with funding support from BOEM/DoI.

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3.      Arctic Storm Activity and its impacts on the Arctic Sea Ice 

Synoptic storms play an important contributing role in the rapidly changing Arctic climate system. In this study funded by NSF, we will investigate the physical processes and mechanism of those persistent storm systems over the Arctic Ocean and their impacts on the Arctic sea ice.

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4.      Storm Activity and Poleward Moisture Transport

Inspired by two studies “Enhanced poleward moisture transport and amplified northern high-latitude wetting trend” (Zhang et al 2012, Nature Climate Change) and “Climatology and Interannual Variability of Arctic Cyclone Activity: 1948–2002” (Zhang et al. 2004, Journal Climate), this study will focus on analyzing the roles of synoptic cyclone systems in poleward moisture transport.

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  5.      Dynamic Downscaling of CMIP5 Climate Scenarios

Sponsored by NSF, a dynamic downscaling of CMIP5 climate scenarios will be downscaled and the downscaled storm activity is a focus in this study.

zhang6

 Most Recent 5 Publications:

  1. Stegall*, S. T., and J. Zhang, 2012, Wind Field Climatology, Changes, and Extremes in the Chukchi/Beaufort Seas and Alaska North Slope during 1979-2009, Journal of Climate, JCLI-D-11-00532, in press.
  2. Zhang, X., J. He, J. Zhang, I. Polaykov, R. Gerdes, J. Inone, & P. Wu, 2012: Enhanced Poleward Moisture Transport Amplifies the Northern High-Latitude Wetting Trend, Nature Climate Change, DOI: 10.1038/NCLIMATE1631, 2012.
  3. Petrich, C., H. Eicken, J. Zhang, J. Krieger, Y. Fukamachi, and K. I. Ohshima, 2011: Coastal landfast sea ice decay and break-up in northern Alaska: Key processes and seasonal prediction, J. Geophys. Res., 117, C02003, doi:10.1029/2011JC007339. 19 PP.
  4. Zhang, J. and X. Zhang, 2010, A Soil Moisture Assimilation Scheme using Satellite-retrieved Skin Temperature in Mesoscale Weather Forecast Model. Atmosphere Research, doi: 10.1016/j.atmosres.2009.09.003.
  5. Bourne*, S.M., U.S. Bhatt, J. Zhang, and R. Thoman, 2010, Surface-based Temperature Inversions in Alaska from a Climate Perspective, Atmosphere Research, doi: 10.1016/j.atmosres.2009.09.013

* student authors

 Most Representative 5 Publications:

  1. Zhang, J., U.S. Bhatt, W.V. Tangborn, and C.S. Lingle, 2007, Climate Downscaling for Estimating Glacier Mass Balances in Northwestern North America: Validation with a USGS Benchmark Glacier, Geophysical Research Letters, doi:10.1029/2007GL031139.
  2. Zhang, J. and J.E. Walsh, 2007, Relative Impacts of Vegetation Coverage and Leaf Area Index on Climate Change in a Greener North, Geophysical Research Letters, 34, L15703, doi:10.1029 /2007GL030852.
  3. Zhang, J. and J.E. Walsh, 2006, Thermodynamic and Hydrological Impacts of Increasing Greenness in Northern High Latitudes, Journal Hydrometeorology, 7, 1147-1163.
  4. Zhang, X., J.E. Walsh, J. Zhang, U.S. Bhatt, and M. Ikeda, 2004, Climatology and Interannual Variability of Arctic Cyclone Activity, 1948-2002, Journal Climate, 17, 2300-2317.
  5. Zhang, J., and Y. Ding, 1999: An improved land surface processes model and its simulation experiment: land surface processes model and its "off-line" tests and performance analyses, Acta Meteorologica Sinica, 13, 257-277.

Recent Collaborators:

Uma S. Bhatt, University of Alaska Fairbanks; Regine Hock, University of Alaska Fairbanks; Jeremy Krieger, University of Alaska Fairbanks; Anna Liljedahl, University of Alaska Fairbanks; Yuh-lang Lin, North Carolina A&T State University; Xingang Fan, Western Kentucky University; Chris Petrich, University of Alaska Fairbanks; Martha Shulski, University of Nebraska Lincoln; Wendell Tangborn, HyMet, Inc.; Chris Yetsko, ConocoPhillips; Xiangdong Zhang, University of Alaska Fairbanks