Electrical structure of PMSE and NLC regions during the DROPPS Program

Croskey, C. L.; Mitchell, John; Friedrich, Martin; Torkar, K.; Hoppe, Ulf-Peter; Goldberg, R. A.

doi:10.1029/2000gl012540

Cited by 55 publications

(62 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Among these flights there is only one case where the sun was above the horizon and illuminated the D-region. This is the flight described by Croskey et al [2001] showing positively charged particles in the altitude range between 70 and 90 km. Since our Arecibo measurements were conducted around local noon (see below), we hence consider it a sound assumption that photo emission has probably resulted in a positive MSP charge.…”

Section: Meteor Smoke Effects On Isr Spectramentioning

confidence: 99%

Meteor smoke particle properties derived from Arecibo incoherent scatter radar observations

Strelnikova

Rapp

Raizada

et al. 2007

Geophysical Research Letters

View full text Add to dashboard Cite

[1] We present a new algorithm to infer information on the properties of charged meteoric smoke particles (MSPs) from the shape of incoherent scatter radar spectra. We show that in the presence of charged MSPs the spectrum can be approximated as the sum of two Lorentzians. These two distinct spectral lines correspond to two diffusion modes in the D-region plasma, i.e., one due the presence of positive ions and one because of heavy charged MSPs. The widths and amplitudes of these two spectral lines yield information on the radius and number density (the latter only for positively charged particles) of the charged MSPs. We apply this new algorithm to measurements obtained with the 430 MHz ISR at Arecibo and demonstrate that the observed spectra indeed bear the features anticipated in the presence of charged MSPs. Resulting values of retrieved MSP number densities and radii fall well within the range of values expected from models and independent in situ observations. Citation: Strelnikova, I., M. Rapp, S. Raizada, and M. Sulzer (2007), Meteor smoke particle properties derived from Arecibo incoherent scatter radar observations, Geophys. Res. Lett., 34, L15815,

show abstract

Section: Meteor Smoke Effects On Isr Spectramentioning

confidence: 99%

Meteor smoke particle properties derived from Arecibo incoherent scatter radar observations

Strelnikova

Rapp

Raizada

et al. 2007

Geophysical Research Letters

View full text Add to dashboard Cite

show abstract

“…12,13 The motivation for those studies was also the understanding of atmospheric phenomena, specifically the reported coexistence of the positively charged particles with an excess electron population in polar mesospheric clouds. 6,14 It was found that photoemission from the Na doped water-ice surface had a surprisingly large cross section ͑Ͼ10 −18 cm 2 per Na atom͒ in the visible region of the spectrum with a threshold near 2.3 eV. 12,13 This is considerably below the 8.7 eV threshold for the ionization of undoped water-ice.…”

Section: Introductionmentioning

confidence: 99%

“…Examples include formation of molecular oxygen and other products during high energy ͑Ͼ10 eV͒ photolysis, 1 hydrogen ion desorption and oxygen generation under electron bombardment, 2 electron and photon-induced chemistry of adsorbates on water-ice, 3,4 and the charging of nanosized ice particles in the mesosphere, leading to reduced mobility of the plasma around the particles and hence to the strong radar backscatter known as polar mesospheric summer echoes. 5,6 The structure, dynamics, and chemistry of electrons solvated in or at the surface of water-ice have attracted particular attention. The ultrafast dynamics of electrons photoinjected into thin water-ice films on metal substrates were studied in detail by Bovensiepen and co-workers.…”

Section: Introductionmentioning

confidence: 99%

Photoelectric emission from the alkali metal doped vacuum-ice interface

Vondrak

Meech

Plane

2009

The Journal of Chemical Physics

View full text Add to dashboard Cite

The photoelectron photoemission spectra and thresholds for low coverages of Li and K adsorbed on water-ice have been measured, compared with photoionization spectra of the gas-phase atoms, and modeled by quantum chemical calculations. For both alkali metals the threshold for photoemission is dramatically decreased and the cross section increased on adsorption to the water-ice surface. Quantum chemical calculations suggest that the initial state is formed by the metal atoms adsorbed into the water-ice surface, forming a state with a delocalized electron distribution. This state is metastable and decays on the hundreds of seconds time scale at 92 K. The decay is markedly faster for Li than for K, probably due to diffusion into the ice film.

show abstract

“…An alternate detector design, the Gerdien condenser, is open at the bottom and allows passage of air through the instrument. There is an upper bound on mass that can be varied by scanning the collector voltage (Croskey et al, 2001), but the scanning results in a loss of altitude resolution. The number density of the charged fraction of the aerosol particles has been deduced from the data of these charge-collecting instruments and is of order 10 3 cm −3 , which is much greater than the number densities of visible NLC particles.…”

Section: Introductionmentioning

confidence: 99%

Mass analysis of charged aerosol particles in NLC and PMSE during the ECOMA/MASS campaign

et al. 2009

View full text Add to dashboard Cite

Abstract. MASS (Mesospheric Aerosol Sampling Spectrometer) is a multichannel mass spectrometer for charged aerosol particles, which was flown from the Andøya Rocket Range, Norway, through NLC and PMSE on 3 August 2007 and through PMSE on 6 August 2007. The eight-channel analyzers provided for the first time simultaneous measurements of the charge density residing on aerosol particles in four mass ranges, corresponding to ice particles with radii <0.5 nm (including ions), 0.5-1 nm, 1-2 nm, and >3 nm (approximately). Positive and negative particles were recorded on separate channels. Faraday rotation measurements provided electron density and a means of checking charge density measurements made by the spectrometer. Additional complementary measurements were made by rocket-borne dust impact detectors, electric field booms, a photometer and ground-based radar and lidar. The MASS data from the first flight showed negative charge number densities of 1500-3000 cm −3 for particles with radii >3 nm from 83-88 km approximately coincident with PMSE observed by the ALWIN radar and NLC observed by the ALOMAR lidar. For particles in the 1-2 nm range, number densities of positive and negative charge were similar in magnitude (∼2000 cm −3 ) and for smaller particles, 0.5-1 nm in radius, positive charge was dominant. The occurrence of positive charge on the aerosol particles of the smallest size and predominately negative charge on the particles of largest size suggests that nucleCorrespondence to: S. Knappmiller (knappmil@colorado.edu) ation occurs on positive condensation nuclei and is followed by collection of negative charge during subsequent growth to larger size. Faraday rotation measurements show a bite-out in electron density that increases the time for positive aerosol particles to be neutralized and charged negatively. The larger particles (>3 nm) are observed throughout the NLC region, 83-88 km, and the smaller particles are observed primarily at the high end of the range, 86-88 km. The second flight into PMSE alone at 84-88 km, found only small number densities (∼500 cm −3 ) of particles >3 nm in a narrow altitude range, 86.5-87.5 km. Both positive (∼2000 cm −3 ) and negative (∼4500 cm −3 ) particles with radii 1-2 nm were detected from 85-87.5 km.

show abstract

Electrical structure of PMSE and NLC regions during the DROPPS Program

Cited by 55 publications

References 7 publications

Meteor smoke particle properties derived from Arecibo incoherent scatter radar observations

Meteor smoke particle properties derived from Arecibo incoherent scatter radar observations

Photoelectric emission from the alkali metal doped vacuum-ice interface

Mass analysis of charged aerosol particles in NLC and PMSE during the ECOMA/MASS campaign

Contact Info

Product

Resources

About