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The Mpc-scale radio source associated with the GPS galaxy B1144+352

A. P. Schoenmakers·A. G. de Bruyn·H. J. A. Rottgering·H. van der Laan
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Abstract

We present the results of new observations of the enigmatic radio source B1144+352 with the WSRT at 1.4 GHz. The WENSS and NVSS surveys have revealed faint extended radio structures on Mpc-scales. We have investigated these large-scale radio components. One of the radio structures has a leading hotspot and we conclude that this structure is a large radio lobe associated with the GPS source. The other contains two separate radio sources which are superposed on the sky: A low-power radio source at a similar redshift (z=0.065) to the GPS host galaxy and an extended radio lobe, which we believe is associated with the GPS host galaxy. Further, the 1.4-GHz flux density of the core has decreased by 70 mJy between 1994 and 1997. We have also retrieved and analysed unpublished archival ROSAT HRI data of B1144+352. The source has been detected and appears to be slightly extended in X-rays. The ROSAT data have not detected a large extended X-ray halo surrounding the host galaxy, limiting the luminosity of the intra-cluster gas within a radius of 250 kpc to < 2.3 x 10^42 erg/s. B1144+352 is the second GPS galaxy known to be associated with a Mpc-sized radio source, the other being B1245+676. We argue that the observed structures must be the result of an interrupted central jet-activity, and that as such these sources may well be the progenitors of double-double radio galaxies.

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A. P. Schoenmakers, A. G. de Bruyn, H. J. A. Rottgering, H. van der Laan. 1998-10-12. The Mpc-scale radio source associated with the GPS galaxy B1144+352. https://arxiv.org/abs/astro-ph/9810178

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