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Scientific resultsRomanenko L. G., Izmailov I. S. Central Astronomical Observatory at Pulkovo, Russian Academy of Sciences, Saint Petersburg, Russia
We use a modified method of the apparent motion parameters (AMP), in which
the initial data from the Gaia DR2 catalog are not only highprecision
coordinates, parallaxes, and radial velocities of the components of
the studied wide binary stars, but are also their proper motions.
The coincidence of the AMP orbits obtained both from the Gaia DR2 data
and from the Pulkovo series from 19602019 leads to an orbit that is
unambiguous in terms of an ascending node. The results for improving
the orbits of such visual binaries of the Pulkovo research program as
ADS 246, 2757, 10386, and 12169 are presented. Orbits (with periods of 1226,
1075, 4500, and 4900 years), orbital orientation parameters in the Galaxy
coordinate frame, and the masses of these systems are obtained (0.59+/0.05,
1.7+/0.3, 1.7+/0.4, and 2.25+/0.5 solMass). It is shown that dense
homogeneous series of groundbased observations, such as CCD observations
with the 26inch refractor of the Pulkovo Observatory, do not lose their
relevance, serve as the basis for identifying the best solution based on
both Gaia data and our own observations, and should be continued. It was
also shown that the ThieleInnes method is not suitable for determining
the orbits of binary stars with a separation of more than 100 AU.
at Pulkovo observatory with 26inch refractor during 2014  2019. Igor Izmailov^{1}, Aleksey Rublevsky^{2}, Arina Apetyan^{1} ^{1}Central Astronomical Observatory at Pulkovo, Russian Academy of Sciences, Saint Petersburg, Russia ^{2}Crimean Astrophysical Observatory, Russian Academy of Sciences, Crimea, Nauchny Russia
We present 18,365 astrometric observations of 290 visual binaries obtained with the 26inch
refractor of Pulkovo Observatory during 2014–2019. The separation between components
is from 1".3 to 37" with a median value of 4".8. For a single observation, the mean
separation error is 0".013, and the mean position angle error is 0^{o}.44/ρ, where ρ is
an angular distance in arcseconds. We compare the observations of sample stars with the data from the
Gaia DR2 catalog and the results of the groundbased observations performed with other telescopes.
Izmailov I. S. Central Astronomical Observatory of RAS at Pulkovo
Based on positional observations, we have determined the orbits of 130 visual double stars for the first time and improved the orbits of 321 stars.
The histogram of eccentricities for all of the derived orbits
corresponds to the relation f = 2e. The period distribution has two pronounced maxima at P ≈ 200 and
≈ 550 yr. The ephemeris relative positions and their errors have been calculated for the next three years.
tilin132_win32.zip tilin132_win64.zip
The input file for this program is 'input.txt'.
Program 'Precess' takes into account the precession using the formula:
The data source is file 'source.txt' Izmailov, I. S.; Roshchina, E. A.
We studied the possibility of flat solutions for triple systems. For the analysis we chose the systems of type I: a close pair with a distant companion, with known orbits where the satellite shows significant relative motion. We calculated two variants of the orbit for the wide pairs — with the condition of coplanarity of orbits of close and wide pair, and without it. If the sum of squared residuals for orbit determined with the condition is not increased, it may be assumed that the system is flat. Among reviewed fifteen triple systems, the following ones may be flat: WDS 20474+3629, 00321+6715, 011980031, 02291+6724, 052390052, 060033102, 08122+1739, 103700850, 17066+0039. Other systems are not able to have the coplanar orbits of wide and close pair: WDS 8592+4803, 013502955, 02022+3643, 04400+5328 and 08468+0625. Three of them have a retrograde motion.
Izmailov I. S., Khovritcheva M. L., Khovritchev M. Yu., Kiyaeva O. V., Khrutskaya E. V., Romanenko L. G., Grosheva E. A., Maslennikov K. L., Kalinichenko O. A. Central Astronomical Observatory of RAS at Pulkovo
We present the results of 3489 astrometric CCDmeasurements of 361 visual double stars performed with the 26inch refractor of the Pulkovo observatory in 2003  2007.
Angular separations (rho) and position angles (theta) are provided. Mean values of standard errors are 0".009 in rho and 0.40(deg)/rho in theta, where rho is the separation in arcseconds.
I. S. Izmailov and E. A. Roshchina Central Astronomical Observatory of RAS at Pulkovo
We present the results of 15 184 astrometric observations of 322 visual binaries carried out in 2007–2014
at Pulkovo observatory. In 2007, the 26inch refractor (F = 10 413 mm, D = 65 cm) was equipped
with the CCD camera FLI ProLine 09000 (FOV 12´×12´
, 3056×3056 pixels, 0.238 arcsec/pixel).
Telescope automation and weather monitoring system installation allowed us to increase the number of
observations significantly. Visual binary and multiple systems with an angular distance in the interval
1″.1–78″.6 with 7″.3 on average were included in the observing program. The results were studied in
detail for systematic errors using calibration star pairs. There was no detected dependence of errors on
temperature, pressure, and hour angle. The dependence of the 26inch refractor’s scale on temperature
was taken into account in calculations. The accuracy of measurement of a single CCD image is in the
range of 0″.0005 to 0″.289, 0″.021 on average along both coordinates. Mean errors in annual average values
of angular distance and position angle are equal to 0″.005 and 0°.04 respectively. The results are available
here http://izmccd.puldb.ru/vds.htm and in the Strasbourg Astronomical Data Center (CDS). In the
catalog, the separations and position angles per night of observation and annual average as well as errors
for all the values and standard deviations of a single observation are presented. We present the results of
comparison of 50 pairs of stars with known orbital solutions with ephemerides.

MULTISAT Pulkovo Observatory SAI Moscow University Institute of Applied Astronomy of RAS SAO RAS Institute of astronomy of RAS AO of St. Petersburg state University USNO CDS, Strasbourg Astronom.RechenInst. Heidelberg Nikolaev Observatory MAO, NAS of Ukraine 

© Igor Izmailov 