Combined determination of stream activity and Observability Function
Chris Steyaert
[email protected]
One year of radio meteor counts • VVS beacon observers
• Sporadics versus streams • Reliable ? Armagh september 2010
VVS
Chris Steyaert
2
IMC2005 presentation Gaspard De Wilde Perseids 2005
Armagh september 2010
VVS
Chris Steyaert
3
Reference • A numerical method to aid in the combined determination of stream activity and Observability Function Steyaert, Christian; Brower, Jeffrey; Verbelen, Felix
WGN, Journal of the International Meteor Organization, vol. 34, no. 3, p. 87-93 Метод Стиерта Предложенный метод анализа данных любительских радионаблюдений метеорных потоков был предложен Кристианом Стиертом (Christian Steyaert) в 2005 году на Международной метеорной конференции в Оостмале (Oostmall), Бельгия, и детально описан в статье [*Christian Steyaert, Jeffrey Brower, and Felix Verbelen, WGN, the Journal of the IMO 34:3 (2006)*]. Рассмотрим суть этого метода. Armagh september 2010
VVS
Chris Steyaert
4
Some maths
O S Z OF tM a b
observed ‘activity’ sporadic background stream profile Observability Function instance of maximum rise time constant decay
Armagh september 2010
VVS
Chris Steyaert
5
Geminids 2005
Brower Verbelen
Armagh september 2010
VVS
Chris Steyaert
6
Geminids 2005
Observed = Sporadic + Stream * ObsF
Armagh september 2010
VVS
Chris Steyaert
7
Geminids 2005
Obs F Sporadic
Armagh september 2010
VVS
Chris Steyaert
8
Geminids predictions
Armagh september 2010
VVS
Chris Steyaert
9
Geminids 2005-2009
Observed = Sporadic + Stream * ObsF
Armagh september 2010
VVS
Chris Steyaert
10
Geminids 2005-2009 Avg OF 5 years Geminids Verbelen 160 140 120 100 80 60 40 20 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Avg Sporadics 5 years Geminids Verbelen 10
5
0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Armagh september 2010
VVS
Chris Steyaert
11
Observed versus true maximum
Armagh september 2010
VVS
Chris Steyaert
12
Conclusions / the future • Combined stream and OF method works – well in the easiest case: major stream, one maximum – not as good in the other cases • Solutions / possibilities – re-utilise the determined OF values of each stream per observer – combine observations of several observers • non analytical method – AI, esp. neural networks
• Growing network Armagh september 2010
VVS
Chris Steyaert
13
Thanks to • • • • • •
Felix Verbelen David Entwistle Willy Camps Jeff Brower Astrolab IRIS, Zillebeke VVS
Armagh september 2010
VVS
Chris Steyaert
14
