We are moving. After about Sept. 1, 2012, we
will be at cips.colorado.edu.
Last update: April 16,
2012
A research group with members from the Center for Integrated Plasma Science (CIPS) and
the Laboratory for Atmospheric and Space Physics
(LASP) at the
The webmaster is Scott Robertson.
CHAMPS successful rocket launches:
We launched two sounding rockets from the Andoya Rocket Range, Oct.11 and Oct. 13, 2011, and our particle mass spectrometer returned data on meteoric dust particles. The campaign was called CHAMPS: charge and mass of meteoric smoke particles.
A first look at the data was reported at the January URSI Radio Science meeting in Boulder.
Here is the talk at URSI given by Shannon Dickson: URSI_CHAMPS_Jan2012_1.pdf
Here is a talk that Scott Robertson gave at the Center for Integrated Plasma Studies on February 3:
Special Issue on the 12th Workshop on the Physics of Dusty Plasmas [May 2010]
The 12th Workshop on the Physics of Dusty Plasmas
was held in Boulder, May 17-20, 2009. The Special Issue of the IEEE
Transactions on Plasma Science on Dusty Plasmas containing papers from this
conference has now appeared.
The Table of Contents can be viewed at: http://ieeexplore.ieee.org/xpl/tocresult.jsp?isnumber=5444581
I. The MASS rocket campaign
This rocket campaign
was conducted in August 2007 to find the size and altitude distribution of
charged aerosol particles responsible for noctilucent clouds. Data analysis
(mostly by Scott Knappmiller) is continuing through 2010.
Special Issue on the ECOMA/MASS Rocket Campaign [May 2010]:
The results of our
MASS rocket flights and the European ECOMA rocket flights has now appeared in a
special issue of Annales Geophysicae published by the European Geophysical
Union. The papers can be found at the journal by searching
"ECOMA/MASS."
The preface can be
viewed at: http://www.ann-geophys.net/prefaces/preface219.pdf
Special Issue papers,
2010:
1. “Mass analysis of charged aerosol particles in NLC and
PMSE during the ECOMA/MASS campaign,” S. Robertson, M. Horányi, S. Knappmiller,
Z. Sternovsky, R. Holzworth, M. Shimogawa, M. Friedrich, K. Torkar, J. Gumbel,
L. Megner, G. Baumgarten, R. Latteck, M. Rapp, U.-P. Hoppe and M. E. Hervig,
Annales Geophysicae 27, 1213-1232, 2009.
2. “Electric field measurements in a NLC/PMSE region
during the MASS/ECOMA campaign,” M. Shimogawa and R. Holzworth, Annales
Geophysicae 27, 1423-1430, 2009.
3. “Signatures of Mesospheric Particles in Ionospheric
Data,” M. Friedrich, K.M. Torkar, W. Singer, I. Strelnikova, M. Rapp, and S.
Robertson, Annales Geophysicae 27, 823-829, 2009.
4. “Large mesospheric ice particles at exceptionally high
altitudes,” L. Megner, M. Khaplanov, G. Baumgarten, J. Gumbel, J. Stegman, B.
Strelnikov and S. Robertson, Annales Geophysicae 27, 943-951, 2009.
5. “First in situ measurement of the vertical
distribution of ice volume in a mesospheric ice cloud during the ECOMA/MASS
rocket-campaign,” M. Rapp, I. Strelnikova, B. Strelnikov, R. Latteck, G.
Baumgarten, Q. Li, L. Megner, J. Gumbel, M. Friedrich, U.-P. Hoppe, and S.
Robertson, Annales Geophysicae 27, 755–766, 2009.
Older
stuff about the rocket campaign:
A. Zoltan's Quicktime movie of the first rocket launch: MASS_movie.MOV (August, '07)
B. Photo gallery from the rocket campaign: My trip to Norway.htm (August, '07)
C. Power Point from Spring 2006 AGU saying what we are going to do: Manuscript_links\AGU_SA53A-04.pdf (May '07)
D. Power Point for the Fairbanks LPMR meeting showing that we have done it: Manuscript_links\LPMR_Fairbanks_4.pdf (Sept. '07)
E. Public talk on the preliminary results from the campaign: Manuscript_links\CIPS_TALK_5.pdf (Nov. '07)
F. Fall 2007 AGU poster on the MASS results: Manuscript_links\AGU_poster_2007_MASS_results.pdf (Dec. '07)
G. Public talk on MASS results (upleg of MASS#1) given at LASP, 28 February 2008: Manuscript_links\LASP_TALK.ppt (Feb. '08)
II. Colorado Center for Lunar Dust and
Atmospheric Studies
The Center is a node
of the NASA Lunar Science Institute. CCLDAS was established April 2009 for four
years. The Center will study the dusty plasma environment at the lunar surface.
Activities include construction of a dust accelerator facility and several
large vacuum chambers for study of dusty surfaces in a simulated space
environment and for development of instruments for the lunar surface and for
lunar orbiters.
The Center has its
own set of web pages: http://lasp.colorado.edu/ccldas/
Dust on the moon - an overview of the lunar dust problem (by David Alexander, 1996): A trip to the Moon
III. Very cold plasma,
through understanding particle and energy balance [undergraduate research
projects]
This effort is aimed
at understanding why laboratory plasmas have a temperature of order 1 eV. The electrons
from electron-impact ionization have an energy spread of order 15 eV, so why is
the plasma temperature often 1-2 eV? We have shown that this temperature (in
hot-filament lab discharges) is a balance between evaporative cooling of
electrons, the energy that the electrons have at birth, and the energy gained
by the “thermal” electrons through collisions with suprathermal electrons (see
the “earlier stuff” link below). It is important to divide the electrons into
“hot” and “thermal” populations in order to get a meaningful result.
Earlier cold plasma
stuff from 2005 and 2006: Particle and energy balance
Senior undergrad
Ward Handley was able to reduce the electron temperature to room temperature [~300 K] by minimizing
the population of suprathermal electrons. Electrons from the filaments transfer
energy to the plasma electrons, but more slowly than the transfer of energy
from secondary electrons originating at the wall. Recall that higher energy
electrons have a lower collision frequency. The reference is: “A hot-filament
discharge with very low electron temperature,” Ward Handley and Scott
Robertson, Physics of Plasmas 16, 016702 (2009).
Senior undergrad
Shannon Dickson further reduced the temperature to ~200 K, which we
think is a record low electron temperature for continuous plasma. This low
temperature was created by (1) starting with Ward’s experiment having a low
secondary emission from the wall, (2) cooling the wall of a liner with liquid
nitrogen, and (3) using carbon monoxide as the working gas so the electrons are
more quickly cooled by collisions with the cold gas. Note that CO has a dipole
moment that increases the collision rate with electrons. The reference is
“Continuous gas discharge plasma with 200 K electron temperature,” S. Dickson
and S. Robertson, Physics of Plasmas 17, 033508 (2010).
V. Smoky Plasma: The mesosphere in the laboratory (started in Fall ’06): Smoky Plasma Experiment
VI. Langmuir probe research (updated May 2010)
Laframboise used a
kinetic model to find the current to spherical and cylindrical probes. Scott
R., while on a sabbatical leave, decided to write a computer code with
Laframboise model in order to have the capability of reproducing Laframboise
probe curves and for generating curves for conditions not covered in
Laframboise papers. Here is the reference: “Reformulation of
Laframboise' Probe Theory in Cylindrical Geometry and the Absence of an Ion
Saturation Current,” Scott Robertson, IEEE Transaction on Plasma Science 38(4),
p. 781-787, April 2010.
Here is what we did through 2007: Probe research
VII. Presheath, sheath, and ion mobility research (through 2006): Presheath & sheath research
VIII. The annular Penning Trap project (which ended in year 2000): The Annular Penning Trap Project
Very old web pages (mostly from 2002 and earlier):
The Dusty
Plasma Group Research Activities
Rocket shots into the ionosphere
APS October 20 03
poster: Poster on the rocket-borne charged aerosol detector
Ion current to Langmuir probes is
increased a lot
by charge exchange collisions
Dust charging by plasmas, plasma sheaths, and UV
Orbiting dust particles in the lab
Lunar dust charging
Education: Learning plasma physics:
These exercises in the mathematical spreadsheet
"Mathcad" show how to use numerical methods for many types of plasma
physics problems.
Go to: plasma.colorado.edu/mathcad (this is an html document, but
you need Mathcad to run the exercises)
Or, try this link: Physics 4150 Mathcad Exercises
Links to related
sites
CIPS homepage (Center for Integrated Plasma Studies at CU)
LASP homepage (Laboratory for Atmospheric and Space Physics at CU)
Colorado Center for Lunar Dust and Atmospheric Studies: http://lasp.colorado.edu/ccldas/
Photo Gallery: The Dusty Plasma Group Investigators (updated January 2008)
E-mail directory (revised May, 2010), to each of these add @colorado.edu unless otherwise noted
Shannon Dickson, Shannon.dickson
Mihaly Horanyi, mihaly.horanyi
Scott Knappmiller, scott.knappmiller
Scott Robertson, scott.robertson
Zoltan Sternovsky, zoltan.sternovsky
Xu Wang, xu.wang
Phone directory:
Plasma physics laboratory: 303-492-5565 (for Scott
R., Scott K., Xu, Shannon, and Devin)
For Tobin Munsat's area: 303-492-2010.
Carolyn James, Administrative Assistant: 303-492-8760
Plasma group FAX machine: 303-492-0642
Some of the departed:
Josh Colwell, josh.colwell AT physics.ucf.edu
Bob Walch, robert.walch AT unco.edu
Ward Handley is now at LASP.
Extraneous activities:
The summer 2006 lab hike to the top of St. Vrain peak (12,162 ft.) in Rocky Mountain National Park beginning at the Allenspark trailhead. From left to right: Maria Handley, Ward Handley, Scott Knappmiller, Scott Robertson and Tobin Munsat. The picture is by Zoltan Sternovsky. For a trail description go to: http://protrails.com/trail.php?trailID=117.