J/A+A/320/631 Meteor streams detected among 502TV (Jopek+ 1997)
A stream search among 502TV meteor orbits. An objective approach
Jopek T.J., Froeschle C.
<Astron. Astrophys. 320, 631 (1997)>
=1997A&A...320..631J 1997A&A...320..631J (SIMBAD/NED BibCode)
ADC_Keywords: Solar system
Keywords: meteors
Abstract:
In the first part of the paper a short review of the computer meteor
stream searching techniques is given. Different fractions of the
stream component obtained amongst radio, photographic and TV data are
partially due to the use of different methods applied in the stream
search. A new objective approach is proposed in order to obtain the
threshold value Dc of the orbital similarity corresponding to the
probability of chance occurrence of the stream. The 502 Canadian TV
data has been used to test this approach. It appears, that the values
of Dc given by Southworth & Hawkins (1963, Smith. Cont. Aph. 7, 261)
and Lindblad (1971, Smith. Cont. Aph. 12, 14) formulae are too high to
warrant sufficient reliability of the identified streams. Indeed using
these formulae the result is that the probability to obtain by chance
at least one stream of 4-5 members goes from 21% to 68%. The effect of
the three different distance functions used to measure the orbital
similarity (Southworth & Hawkins (1963, Smith. Cont. Aph. 7, 261),
Drummond (1979, 1981Icar...45..545D 1981Icar...45..545D), and Jopek 1993) has been
investigated. For all functions taking the same 95% reliability level,
the number of streams detected is considerably less than in the case
of the traditional approach (Jopek 1993Icar..106..603J 1993Icar..106..603J). However,
results are different using different distances. Finally, we give the
list of the orbits of eight streams identified at the reliability
level WM=95% using the Jopek distance.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table6-7.dat 66 67 List of the members of meteor streams detected
among 502 TV orbits by D_H similarity function
at reliability level W_M=95%
tables.tex 96 208 LaTeX version of the tables
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Byte-by-byte Description of file: table6-7.dat
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Bytes Format Units Label Explanations
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1 I1 --- Type [1/8] Type of meteor stream (1)
3- 4 I2 yr UTC.Y Universal time of the meteor instant (year)
6- 7 I2 "month" UTC.M Universal time of the meteor instant (month)
9- 13 F5.2 d UTC.D Universal time of the meteor instant (day)
15- 19 F5.3 --- e Orbital eccentricity
21- 25 F5.3 AU q Perihelion distance
27- 31 F5.1 deg PLON Longitude of perihelion
33- 37 F5.1 deg LON Longitude of the ascending node
39- 43 F5.1 deg i Inclination of the orbit plane to the ecliptic
45- 49 F5.1 deg alphaR Geocentric rectascention of the corrected radiant
51- 55 F5.1 deg deltaR Geocentric declination of the corrected radiant
57- 60 F4.1 km/s VG Geocentric corrected velocity
62- 66 F5.1 deg lambda Elongation of the corrected radiant from the apex
of the Earth's motion
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Note (1): Classes defined as follows:
1 = S. Taurids, 13 members identified at DcW=0.169
2 = S. Taurids-Arietids, 10 members identified at DcW=0.169
3 = α Capricornids, 12 members identified at DcW=0.169
4 = κ Cygnids, 10 members identified at DcW=0.169
5 = δ Aquarids, 9 members identified at DcW=0.163
6 = Perseids, 6 members identified at DcW=0.149
7 = Cyclids, 5 members identified at DcW=0.114
8 = ε Pegasids, 2 members identified at DcW=0.034
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Appendix: Means (M) and standard deviation (sd) for the meteor streams
parameters listed in table6 and table7
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Type e q PLON LON i alphaR deltaR VG lambda
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M 1 0.791 0.404 149.3 39.2 3.4 48.5 13.4 26.5 80.4
Sd 1 0.083 0.090 7.7 2.9 7.9 4.5 8.4 3.6 3.6
M 2 0.720 0.335 126.8 359.9 2.9 18.1 4.5 23.6 72.5
Sd 2 0.085 0.078 7.7 7.0 5.5 7.2 3.5 3.5 4.3
M 3 0.751 0.602 32.3 125.1 12.5 303.7 -3.3 22.7 90.2
Sd 3 0.056 0.057 6.0 3.9 7.1 3.4 9.1 2.2 4.5
M 4 0.647 0.902 352.2 130.5 27.9 286.5 36.0 20.2 96.7
Sd 4 0.077 0.075 10.9 7.6 3.9 6.7 11.3 1.9 5.1
M 5 0.960 0.104 93.9 307.2 27.8 339.7 -18.3 39.7 63.7
Sd 5 0.019 0.034 5.9 0.7 5.1 1.0 3.2 1.8 1.9
M 6 0.721 0.910 277.6 138.9 112.1 49.5 57.1 56.2 39.5
Sd 6 0.123 0.014 4.6 0.0 1.8 1.0 0.6 1.8 0.6
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Acknowledgements: Tadeusz Jan Jopek
(End) Patricia Bauer [CDS] 12-Aug-1996