15 research outputs found
Origin of the complex radio structure in BAL QSO 1045+352
We present new more sensitive high-resolution radio observations of a compact
broad absorption line (BAL) quasar, 1045+352, made with the EVN+MERLIN at 5
GHz. They allowed us to trace the connection between the arcsecond structure
and the radio core of the quasar. The radio morphology of 1045+352 is dominated
by a knotty jet showing several bends. We discuss possible scenarios that could
explain such a complex morphology: galaxy merger, accretion disk instability,
precession of the jet and jet-cloud interactions. It is possible that we are
witnessing an ongoing jet precession in this source due to internal
instabilities within the jet flow, however, a dense environment detected in the
submillimeter band and an outflowing material suggested by the X-ray absorption
could strongly interact with the jet. It is difficult to establish the
orientation between the jet axis and the observer in 1045+352 because of the
complex structure. Nevertheless taking into account the most recent inner radio
structure we conclude that the radio jet is oriented close to the line of sight
which can mean that the opening angle of the accretion disk wind can be large
in this source. We also suggest that there is no direct correlation between the
jet-observer orientation and the possibility of observing BALs.Comment: 8 pages, 3 figures, accepted for publication in Ap
Sunyaev Zel'dovich observations of a statistically complete sample of galaxy clusters with OCRA-p
We present 30 GHz Sunyaev Zel'dovich observations of a statistically complete
sample of galaxy clusters with OCRA-p. The clusters are the 18 most X-ray
luminous clusters at z > 0.2 in the ROSAT Brightest Cluster Sample. We correct
for contaminant radio sources via supplementary observations with the Green
Bank Telescope, also at 30 GHz, and remove a cluster that is contaminated by an
unresolved X-ray source. All 17 remaining clusters have central SZ effects with
Comptonisation parameter y_0 exceeding 1.9x10^-4, and 13 are detected at
significance > 3 sigma. We use our data to examine scalings between y_0 and
X-ray temperature, X-ray luminosity, and the X-ray mass proxy Y_X, and find
good agreement with predictions from self-similar models of cluster formation,
with an intrinsic scatter in y_0 of about 25%. We also comment on the success
of the observations in the face of the contaminant source population, and the
implications for upcoming cm-wave surveys.Comment: 14 pages, 2 figures, accepted by MNRA
Report on meteorite field search within PFN in 2016/2017 season
The Meteorite Section was created in 2010 on demand of Polish Fireball Network (PFN) for the meteorite searching and investigation purposes. The main task of the Section is to find the meteorites dropped from bolides registered by the Polish Fireball Network. Each year, the PFN registers several meteorite falls within our country and meteorite strewnfield inspections must be carried out at least for the masses of above 300 g estimated with the PyFN software. Only last year the PFN organized several search campaigns. Two of them are presented in the publication