1. March 13, 2009 - CCLDAS Particle-in-Cell Simulations of the Lunar Dusty Plasma Environment A. Poppe & M. Horányi Laboratory for Atmospheric and Space Physics Dept. of Physics, Univ. of Colorado at Boulder

2. March 13, 2009 - CCLDAS Research Questions What are the properties of the lunar plasma environment due to photoelectron emission, exposure to solar wind, etc.? What are the required conditions for electrostatic dust charging, levitation and transport? How well do ongoing laboratory measurements reproduce the lunar environment?

3. March 13, 2009 - CCLDAS Particle-in-Cell Code First model is 1-d, without dust particles –Goal is to characterize the properties of the photoelectron sheath present on the dayside of the Moon Grard & Tunaley [1971] present analytical solutions to electron density, electric field and sheath thickness for three electron distributions

4. March 13, 2009 - CCLDAS 1-d PIC Results Monokinetic electron velocity distribution (T=3eV)

5. March 13, 2009 - CCLDAS 1-d PIC Results Rectangular electron velocity distribution (T=3eV)

6. March 13, 2009 - CCLDAS 1-d PIC Results Maxwellian electron velocity distribution (T=3eV)

7. March 13, 2009 - CCLDAS 1-d PIC Results Define a more realistic photoelectron energy distribution (after Feuerbacher et al. 1972) E max = 6 eV E avg = 2.2 eV

8. March 13, 2009 - CCLDAS 1-d PIC Results Feuerbacher et al., 1972 electron velocity distribution

9. March 13, 2009 - CCLDAS Future Work Additions to the 1-d code: –Presence of solar wind ions/electrons –Dependence on emission current Development of 2-d code –Topography / Time-variation Eventual inclusion of dust particles Comparison with laboratory experiments