Combined observations of meteors by image-orthicon television camera and multi-station radar

Observations from multiple sites of a radar network and by television of 29 individual meteors from February 1969 through June 1970 are reported. Only 12 of the meteors did not appear to fragment over all the observed portion of their trajectories. From these 12, the relation for the radar magnitude to the panchromatic absolute magnitude was found in terms of velocity of the meteor. A very tentative fit to the data on the duration of long enduring echoes versus visual absolute magnitude is made. The exponential decay characteristics of the later parts of several of the light curves are pointed out as possible evidence of mutual coalescence of droplets into which the meteoroid has completely broken

Test of candidate light distributors for the muon (g−-2) laser calibration system

The new muon (g-2) experiment E989 at Fermilab will be equipped with a laser calibration system for all the 1296 channels of the calorimeters. An integrating sphere and an alternative system based on an engineered diffuser have been considered as possible light distributors for the experiment. We present here a detailed comparison of the two based on temporal response, spatial uniformity, transmittance and time stability.Comment: accepted to Nucl.Instrum.Meth.

Non-invasive, multichromatic eye oximeter Final report

Optical eye oximeter for measuring oxygen of choroidal blood for monitoring brain oxygen suppl

Simultaneous radar and video meteors

The goal of this thesis is to better understand the physical and chemical properties of meteoroids by using simultaneous radar and video observations of meteors. The Canadian Meteor Orbit Radar (CMOR) and several Gen-III image-intensified CCD cameras were used to measure common meteors and validate metric errors determined through Monte Carlo modelling and to relate radar electron line density (q) to video photon radiant power (I). By adopting an ionisation coefficient from Jones (1997) and using recorded measurements of q/I, a corresponding estimate of the fraction of meteoroid kinetic energy loss converted into light (luminous efficiency) was found. It was found that 7% ± 3% of video meteors were also simultaneously detected as specular echoes by radar, larger than the expected 2% − 5% from modelling. Errors in the fiducial picks for video meteors were found to be anisotropic, with video speeds being higher on average compared to radar speeds, consistent with more deceleration in specular radar measurements. Most radar detections occurred near the end of their meteor trails, suggesting simultaneous observations are biased towards larger, non-fragmenting meteoroids. The peak luminous efficiency was found to be 5.9% at 41 km/s. The magnitude scale and electron line density were found to relate as M = (38.7 ± 1.2) − 2.5 log10 q. These results suggest the masses of higher speed meteoroids are an order of magnitude smaller than previously thought, implying the total meteoroid mass influx for small meteoroids is below earlier estimates. The main uncertainties associated with this analysis are the unknown spectra of individual meteors (which affects estimates of I), and assumptions of the initial meteor trail radius (which affects estimates of q). To improve future simultaneous comparisons, an automated video meteor observatory was constructed. This system, named the Canadian Automated Meteor Observatory (CAMO), features a guided camera which tracks meteors in real-time, giving higher precision video measurements of deceleration and fragmentation for comparison to radar measurements. CAMO can also be used to constrain numerical meteoroid ablation models and to measure the meteoroid mass in-flux at Earth

On the accuracy of PLIF measurements in slender plumes

The purpose of this article was to assess the measurement uncertainty of the planar laser-induced fluorescence (PLIF) method and, as much as possible, to devise corrections for predictable biases. More specifically, we considered the measurement of concentration maps in cross sections parallel to and normal to the axis of a slender plume containing Rhodamine 6G as a passive scalar tracer and transported by a turbulent shear flow. In addition to previously examined sources of error related to PLIF, we also investigated several unexplored ones. First, we demonstrated that errors would arise if the laser sheet thickness was comparable to or larger than the thickness of the instantaneous plume. We then investigated the effect of secondary fluorescence, which was attributed to absorption and re-emission of primary fluorescence by dye both within and outside the laser sheet. We found that, if uncorrected, this effect would contaminate the calibration as well as the instantaneous concentration measurements of the plume, and proposed methods for the correction of these errors and for identifying the instantaneous boundaries of the in-sheet dye regions