Research Information System
XXXth General Assembly of the International Astronomical Union, Viyana, Austria, 20 - 31 August 2018, vol.1, no.1, pp.1, (Full Text)
The program of experimental studies as full as possible sample of kilometer sized NEAs
are carrying out with the 1.5m Russian-Turkish telescope RTT150. The results of polarimetric
and photometric observations in V bandpass of 32 NEAs (23 objects with
diameter larger than 1 km and 9 of them only a few hundred meters in diameter) with
high proper motion in period of theirs close approaches performed at RTT150 between
the August 2014 and June 2018 are presented (regular observations had begun only in the
spring 2018). The estimation of albedo and diameters of asteroids were made by means
of polarimetric and photometric data. Due to that sources were observed at large phase
angles from 40 to 100 degrees for di erent asteroids the measured linear polarization
degree makes it possible to di erentiate the taxonomy classes of observed sources even
using single shot as well. The highest polarization 27.1% was found for 164201 on phase
angle 75. Taking into account the high inclination of the object (35), the 164201
have a possibility to be a cometary nuclei. All objects smaller 1 km were eliminated from
analysis and remaining 23 NEAs were separated on two groups according to obtained
albedo: 0.10<MODERATE (55%)< 0.35, LOW (40%)<0.10. For each group the probability
density function of NEA perihelion was built as a fraction of asteroid number
inside of given interval of perihelion parameter (q=0.3). It seems to be that there is increasing
of moderate albedo NEAs with perihelion parameter. However, it may be due to
incompleteness of sample. In addition to polarimetric determination, the spectral class of
NEA 333888 was estimated as Sq using the low resolution spectra (R600, covered whole
visual range from 4000A to 9000A) obtained with RTT150 facilities. Complex observations
in frame of project will be continued. To avoid the loss of darker kilometer sized
NEAs the object observational list will be broadened with 416 more NEAs which meet
the conditions: q<0.6, 18.0m<H<19.5m. To estimate photometric slope G, and shape of
the project NEAs the additional long-term photometric observation in V-band will be
performed at phase angle of 10 { 60 on T100 (100 cm) and T60 (60 cm) telescopes of
the TUG Observatory.