O(1S) Effective LifetimesEntry ID: ASAC_43
Abstract: Metadata record for data from ASAC Project 43
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From the abstract of the referenced paper:
Intensity time-series with a 0.05 s time resolution were obtained for the 428 nm N2+ (1NG) band and 558 nm O(1S) line emissions during intervals of rapidly fluctuating auroral intensities at Macquarie Island during 1988. Similar measurements have been ... used by previous workers to infer the effective lifetimes of the O(1S) state and the existence of, and percentage contribution from, an indirect excitation process. Using 'constructed data' and an impulse function analysis technique, we introduce a method of analysis that shows that variations in the energy of the precipitating auroral electrons during the intensity fluctuations may be misinterpreted as an indirect excitation process of low percentage contribution. Subsequent to our analysis of the data presented here, we became aware of 'pulse pile-up' contaminations of our raw data files. We have not corrected for this in the examples presented. However, our analysis shows that noise on the intensity time-series by itself, or in combination with the energy fluctuations, may result in a significant over-estimation of the contribution of an indirect excitation process. Measurement of the O(1S) effective lifetime is accurate to within 0.05 s.
The method we introduce allows determination of an upper limit for the misinterpretation as an indirect process of non-linearites known to exist between the 428 nm N2+ (1NG) band and and 558 nm O(1S) line emissions. These non-linearites have been ignored in previous investigations of O(1S) excitation processes.
Data Set Citation
Dataset Originator/Creator: Burns, G.B. and Klekociuk, A.R.
Dataset Title: O(1S) Effective Lifetimes
Dataset Series Name: CAASM Metadata
Dataset Publisher: Australian Antarctic Data CentreOnline Resource: https://data.aad.gov.au/aadc/metadata/metadata_redirect.cfm?md=/AMD...
Start Date: 1992-09-01Stop Date: 1994-03-31
Quality Dates provided in temporal coverage are approximate only.
From the referenced paper:
The optical data were collected at Macquarie Island during 1988 with a twin-channel, beam-splitting photometer with interference filters isolating the N2+ (1NG) (0,1) band at 428 nm and the O(1S-1D) line at 558 nm. The photometer was pointed toward the magnetic zenith and has a one ... degree field-of-view. Data were collected simultaneously from both channels at a rate of 20 Hz. The data are stored, and generally analysed, in five minute blocks. Five minute data sequences are chosen as a compromise between a long data sequence, desirable to reduce the influence of noise, and a short data sequence, desirable so that the parameters being measured remain constant.
This record has been updated by staff at the Australian Antarctic Data Centre (rather than the listed investigator), and therefore it's accuracy and quality cannot be guaranteed.
Access Constraints A pdf copy of the referenced paper is available for download from the provided URL.
Use Constraints This data set conforms to the PICCCBY Attribution License
Please follow instructions listed in the citation reference provided at http://data.aad.gov.au/aadc/metadata/citation.cfm?entry_id=ASAC_43 when using these data.
Data Set Progress
Distribution Media: HTTP
Distribution Size: 1.6 MB
Distribution Format: pdf
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Extended Metadata Properties
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Creation and Review Dates
DIF Creation Date: 2000-07-17
Last DIF Revision Date: 2017-08-24