3 MV hypervelocity dust accelerator at the Colorado Center for Lunar Dust and Atmospheric Studies

Abstract

A hypervelocity dust accelerator for studying micrometeorite impacts has been constructed at the Colorado Center for Lunar Dust and Atmospheric Studies (CCLDAS) at the University of Colorado. Based on the Max-Planck-Institüt für Kernphysik (MPI-K) accelerator, this accelerator is capable of emitting single particles of a specific mass and velocity selected by the user. The accelerator consists of a 3 MV Pelletron generator with a dust source, four image charge pickup detectors, and two interchangeable target chambers: a large high-vacuum test bed and an ultra-high vacuum impact study chamber. The large test bed is a 1.2 m diameter, 1.5 m long cylindrical vacuum chamber capable of pressures as low as 10(-7) torr while the ultra-high vacuum chamber is a 0.75 m diameter, 1.1 m long chamber capable of pressures as low as 10(-10) torr. Using iron dust of up to 2 microns in diameter, final velocities have been measured up to 52 km/s. The spread of the dust particles and the effect of electrostatic focusing have been measured using a long exposure CCD and a quartz target. Furthermore, a new technique of particle selection is being developed using real time digital filtering techniques. Signals are digitized and then cross-correlated with a shaped filter, resulting in a suppressed noise floor. Improvements over the MPI-K design, which include a higher operating voltage and digital filtering for detection, increase the available parameter space of dust emitted by the accelerator. The CCLDAS dust facility is a user facility open to the scientific community to assist with instrument calibrations and experiments.

Magnetic Field Effect on Antenna Signals Induced by Dust Particle Impacts

“…The measurements were carried out using the electrostatic dust accelerator at the University of Colorado (Shu et al, 2012). Briefly, an electrostatic field generated by U acc = 2.2 MV potential is used to accelerate micron-and submicron-sized charged dust particles to velocities of 1-100 km/s.…”

Micrometeoroid impact charge yield for common spacecraft materials

“…Figure a shows the experimental arrangement, using the dust accelerator facility at the University of Colorado [ Shu et al , ]. Submicron‐sized iron projectiles are positively charged and ejected from a dust source, located at the high voltage terminal of a Pelletron electrostatic generator [ Herb , ].…”

“…Figure shows the speed‐mass distribution for all particles used in the scaling tests. The inverse relation between speed and mass is a characteristic of all electrostatic dust accelerators, related to the charging process [ Shu et al , ].…”

The aerosol impact spectrometer: a versatile platform for studying the velocity dependence of nanoparticle-surface impact phenomena

“…The flexibility of single particle on-the-fly analysis allows the Aerosol Impact Spectrometer to function with a wide range of nanoparticle masses and charges from a given particle source. Additionally, the variable energy selection of the spectrometer allows a variety of particle sources to be implemented in addition to the demonstrated electrospray ionization, including liquid metal ion sources [54][55][56] and needle-charge dust sources [57,58]. The wide range of final energies achievable with the variable linear accelerator/decelerator will allow for a variety of scattering experiments to be performed to examine both hypo-and hypervelocity impact phenomena Submit your manuscript to a journal and benefi t from:…”