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1996AR.....40..601Artyukh
The cosmological evolution of compact radio sources at 102 MHz
V.S. Artyukh, S.A. Tyul'bashev
Summary
A survey of compact ( q < 1") radio sources is being made with the
Large Phased Array (LPA) of Lebedev Physical Institute. The
observations are made with the interplanetary scintillations method
at 102 MHz. It was investigated the one area of 7C survey centred
at RA=6h28m and DEC=45d. The investigated square was 0.047 sr. There
have been registered 125 sources with flux densities >0.15 Jy. The
differential counts of the scintillating sources have been made. It
was founded that the scintillating sources counts was close to
sources counts in uniform Euclidean model up to S >0.7 Jy. There is
very steep turnover of scintillating sources counts at S <0.7 Jy, it
is steeper then one of 7C sources counts. This effect is caused by
a different cosmology evolution of compact and extended radio
sources.
1997AR...???..??? submitted! (received from authors)
The cosmological evolution of compact radio sources
from 102 MHz observations.II
V.S. Artyukh, S.A. Tyul'bashev, E.A. Isaev
Summary
A survey of compact (theta < 1'') radio sources with interplanetary
scintillation method was made at 102MHz with the Large Phased Array
of the Lebedev Physical Institute. The survey covers the second
area of the 7C survey, in direction RA = 10h28m and DEC = 41d,
with area 0.097 ster. There were detected 289 scintillating sources.
The survey of scintillating radio sources in two areas of 7C survey
has enabled to detect 414 compact sources, 380 of them 92% were
detect first. The scintillating source count (from observations of
two areas) has confirmed the decrease of the compact radio sources
density for weak flux densities, which we found from observations
of the first area. To flux density S = 0.5 Jy , the differential
count of scintillating sources
differs only little from that expected for a Euclidean Universe but
a very sharp drop in the count curve is observed for weak flux densities
S_102 < 0.5 Jy.
This drop is significantly steeper than that for the 7C survey radio
source count. This result confirms our early conclusion about different
character of the cosmological evolution of compact and extended
radio sources.
Both tables were formatted by S. Tyul'bashev and S.Trushkin