15 research outputs found
Reassessment of an Origin of the Radio Structure of J1420-0545
In this paper, we test the possibility that the structure of the largest radio galaxy J1420-0545 may have been formed by restarted rather than primary jet activity. This hypothesis was motivated by the unusual morphological properties of the source consisting of two edge-brightened, narrow, highly collinear, and symmetric lobes, thus suggesting an almost ballistic propagation of powerful jets into a particularly low-density external medium. New observations made with the VLA together with the currently available gleam and TGSS ADR1 data releases allow the detection of an excess emission at low frequencies. An extracted part (88 MHz-200 MHz) of the spectrum of the emission is fitted with the dynage model, giving a forecast for the environmental conditions and the energetic requirements for the presumed old cocoon related to a preceding epoch of jet activity
Nearby galaxies in the LOFAR Two-metre Sky Survey: I. Insights into the non-linearity of the radio-SFR relation
Galaxie
Intergalactic magnetic fields in Stephan's Quintet
We present results of the VLA radio continuum total power and polarised
intensity observations of Stephan's Quintet at 1.43 and 4.86 GHz along with
complementary 4.85 and 8.35 GHz Effelsberg observations. Our study shows a
large envelope of radio emission encompassing all the member galaxies and hence
a large volume of intergalac- tic matter. Infall of the galaxy NGC 7318B
produces a ridge of intergalactic, polarised emission, for which the magnetic
field strength was estimated as 11.0 \pm 2.2 {\mu}G, with an ordered component
of 2.6 \pm 0.8 {\mu}G. The energy density of the field within the ridge area is
of the same order as estimates of the thermal component, implying a significant
role of the magnetic field in the dynamics of the intergalactic matter. We also
report that the tidal dwarf galaxy candidate SQ-B possesses a strong and highly
anisotropic magnetic field with the total strength being equal to 6.5 \pm 1.9
{\mu}G and an ordered component reaching 3.5 \pm 1.2 {\mu}G, which is
comparable to that found in normal-sized galaxies.Comment: 10 pages, 8 figures, accepted for publication in MNRA
LOFAR M51 field low-frequency polarized sources
Item does not contain fulltextFITS image of Fig. 1 (LOFAR 150MHz total intensity image). 2) Catalog of 201 sources with flux density greater than 100mJy at 150MHz and located within 2.5 degrees of the center of M51. 3) Faraday cubes of 19 sources discussed in Sect. 5. (4 data files)
LOFAR M51 field low-frequency polarized sources
FITS image of Fig. 1 (LOFAR 150MHz total intensity image). 2) Catalog of 201 sources with flux density greater than 100mJy at 150MHz and located within 2.5 degrees of the center of M51. 3) Faraday cubes of 19 sources discussed in Sect. 5. (4 data files)