During July of 1995, 1996 and 1997 CMW observers plotted on gnomonic star maps
2748 paths of meteor events. For each of them the angular velocity was
estimated. We used 0-5 scale with 0 corresponding to stationary meteor,
1 to very slow event, 2 to slow, 3 to medium, 4 to fast and 5 to very
fast meteor. Equatorial coordinates of the begins and ends of these
events and their velocities were put into the RADIANT software
(Arlt 1992). This software as an input also requires the geocentric
velocity of the meteors and the daily drift of the radiant.
Changing both these values we can obtain different density distributions
of the probability area near suspected radiant. Choosing the best
distribution (this one with smallest parameter) we are able to
estimate the values of and the daily drift. The systematic
errors play a role, which are difficult to handle and estimate of the
accuracy of the obtained value of is difficult but the errors
are at minimum km s^{-1}. For more details see Arlt (1993).

Before analyzing our sample we decided to analyze also the meteors observed by
Denning (1919). However we selected only meteors observed by him during
July nights. Number of these events accounted to 20. We performed
our calculation using parameters of the stream given by Jenniskens (1994) i.e.
km s^{-1}, , and
. Results as probability function distribution of the
presence of radiant are presented in Fig. 1. The best fit of the two
dimensional Gaussian surface to the density of probability map gives
coordinates of the radiant equal to and . The
accuracy of this estimate is certainly low due to the small number of
events observed by Denning (1919).

Figure 1:
The radiant of -Cygnids resulting from Denning's
(1919) observations. Assumed parameters are: km s^{-1},
, and
. Number of the events is 20 |

Figure 2:
The radiant of -Cygnids resulting from CMW visual
data. Assumed parameters are: km s^{-1},
, and
. Number of the events is 2748 |

Figure 3:
The radiant of -Cygnids resulting from CMW
telescopic data. Used parameters are: km s^{-1},
, and
. Number of the events is 234 |

Fortunately, the sample collected by CMW observers in years 1995-1997 is
significantly larger. It allows us to derive a few valuable conclusions.
First we calculate our sample (2748 meteors including possible members of
the stream, sporadics and meteors from other showers) using parameters given by
Jenniskens
(1994). During calculation we remove meteors observed at a distance
larger than from the radiant of the stream. The prominence of the
-Cygnid radiant on the resulting picture is striking. The best fit gives
coordinates of the radiant as and .Nevertheless we obtain better results i.e. a
more compact shape of the radiant using geocentric velocity
km s^{-1} and the drift of the radiant ,
. The resulting radiant picture for the above
parameters is displayed in Fig. 2. The final coordinates of the radiant
of -Cygnid stream are and
, which do not differ significantly from coordinates obtained for
parameters given by Jenniskens (1994).

We also used the RADIANT software for the analysis of the paths of our
telescopic meteors. Our sample contains 234 meteors with known paths and
velocities. The resulting density distribution from
telescopic observations is displayed in Fig. 3. The best fit (with
smallest value) is obtained for the following parameters:
geocentric velocity km s^{-1}, the daily drift of the radiant
and . The
coordinates of the center of the radiant are and
. One can see that the position of the radiant
obtained from
telescopic observations differs from the position obtained from visual
data by only . Taking into account that radii of the majority
of radiants vary between and both our results are
strictly consistent. It is also clear that our parameters are in very
good agreement with the data of the one photographed meteor
(Babadzhanov & Kramer 1965).

In years 1995-1997 the CMW observers made as many as 738 and 4546 estimates of the brightness of meteor events from -Cygnids and sporadics, respectively. The distribution of this quantity is presented in Tables 3 and 4.

Such a large amount of magnitude estimates for -Cygnids
encouraged us to compute the value of the population index *r* defined
in Eq. (1). We obtained which is a typical value among
meteor streams. Jenniskens (1994) obtained a similar result with *r* equal
to 2.7. The population index obtained from the magnitudes of our 4546
sporadics is equal to .

Also the telescopic observers estimated the magnitudes of meteor events. The magnitude distributions for 1996 and 1997 -Cygnids and sporadics are presented in Tables 5 and 6.

Knowing the value of *r* we can compute *ZHR* using
the formula given in (3). According to the results of Koschack
(1994) and Bellot (1995) who showed that for visual observations with
radiant altitudes higher than the zenith exponent factor
, we adopted .

Figure 4:
The activity profile of -Cygnids during 1995-1997.
The solid line represents the fit given in Eq. (4) |

The resulting activity profile of -Cygnids in years 1995-1997
is exhibited in Fig. 4. The activity of the stream lasts from
(June 30) to
(July 31). It seems to be slightly wider
than the result of Jenniskens (1994) who noted meteors from -Cygnid
stream in interval . The accuracy of the *ZHR*
estimates by Jenniskens (1994) was low due to the small number of his
observations, therefore we prefer our result.

Our Fig. 4 one exhibits a clear maximum of activity at
with . The error of
this estimate is large but points in the
vicinity of the maximum have smaller errors and their moments and *ZHR*s
are with and
with

The moment of the maximum and its *ZHR* is in very good agreement with
result of Jenniskens (1994) who obtained
with .

Jenniskens (1994) found also that the activity profiles of meteor streams are well represented by the following equation:

(4) |

The CMW observers estimated also the angular velocity of the events. The 0-5 scale (defined in Sect. 3.1 of this paper) was used. Finally we obtained 754 estimates of the angular velocity for -Cygnids and 4339 estimates for sporadics. The velocity distribution from visual observations is presented in Tables 7-8.

We used the above distributions to find another proof for existence of the
-Cygnid stream. We compared empirical velocity distributions of
-Cygnids and sporadics using Kolmogorov-Smirnov and tests. We obtained that with the probability larger than 0.999 both
distributions are different. Such a large probability is certainly
caused by the clear enhancement of meteors with velocity 3 and 4 in
-Cygnid velocity distribution. This result is also is good
agreement with the value of geocentric velocity obtained from RADIANT
analysis of our visual and telescopic data. The meteors with velocity
km s^{-1} given by RADIANT software at mean distance
from the radiant of the stream appear mainly with velocities 3 and 4 in 0-5 scale.

The velocity of meteor events was also estimated by our telescopic
observers. They used *A*-*F* scale with *A* corresponding to the
angular velocity /s and *F* to over s. Finally we
obtained 41 estimates of the angular velocity for telescopic
-Cygnids and 192
velocity estimates for telescopic sporadics. Both distributions are
presented in Tables 9-10.

For telescopic observations the distance from the radiant is generally well defined. Usually it is worthwhile to analyze the mean angular velocity as a function of distance from the radiant. Unfortunately due to the small number of our telescopic -Cygnids which were observed in as many as 10 fields such an analysis is impossible yet.

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