LoTSS jellyfish galaxies

Astronomy and Astrophysics, vol. 652, pp. A153

Abstract

In this paper we report the first identification of jellyfish galaxies in the Perseus cluster (Abell 426). We identified four jellyfish galaxies (LEDA 2191078, MCG +07-07-070, UGC 2654, UGC 2665) within the central 2° ×2° (2.6 Mpc × 2.6 Mpc) of Perseus based on the presence of one-sided radio continuum tails that were detected at 144 MHz by the LOw Frequency ARray (LOFAR). The observed radio tails, as well as the orientation of morphological features in the rest-frame optical, are consistent with these four galaxies being impacted by ram pressure stripping as they orbit through the Perseus intracluster medium. By combining the LOFAR imaging at 144 MHz with 344 MHz imaging from the Karl G. Jansky Very Large Array, we derived spectral indices for the disks and the stripped tails of these jellyfish galaxies. We show that the spectral indices over the galaxy disks are quite flat, while the indices of the stripped tails are substantially steeper. We also identified a number of compact H α + [N II ] sources with narrowband imaging from the Isaac Newton Telescope. These sources are brighter along the leading side of the galaxy (i.e., opposite to the direction of the stripped tail), which is consistent with ram pressure induced star formation. Lastly, consistent with previous works in other clusters, we find that these jellyfish galaxies show enhanced radio luminosities for their observed star formation rates. Given the small distance to the Perseus cluster ( D ∼ 70 Mpc, 1″ ≃ 340 pc), these galaxies are excellent candidates for multiwavelength follow-up observations to probe the impact of ram pressure stripping on galaxy star formation at subkiloparsec scales.

Authors 9

1. Ian D. Roberts Aachen Leiden Observatory

   Leiden University · Leiden Observatory

   Affiliation as printed

   Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands

   Leiden University

2. Reinout J. van Weeren Aachen Leiden Observatory

   Leiden University · Leiden Observatory

   Affiliation as printed

   Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands

   Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, the Netherlands

3. Sean McGee

   University of Birmingham

   Affiliation as printed

   University of Birmingham School of Physics and Astronomy, Edgbaston, Birmingham, UK

   University of Birmingham School of Physics and Astronomy Edgbaston Birmingham UK

4. A. Botteon Aachen Leiden Observatory

   Leiden University · Leiden Observatory

   Affiliation as printed

   Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands

   Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, the Netherlands

5. A. Drabent

   Thüringer Landessternwarte Tautenburg

   Affiliation as printed

   Thüringer Landessternwarte, Sternwarte 5, 07778 Tautenburg, Germany

6. A. Ignesti

   Osservatorio Astronomico di Padova

   Affiliation as printed

   INAF- Osservatorio astronomico di Padova, Vicolo Osservatorio 5, 35122 Padova, Italy

   INAF − Osservatorio Astronomico di Padova, vicolo Osservatorio 5, 35122 Padova, Italy

7. Huub J. A. Röttgering Aachen Leiden Observatory

   Leiden University · Leiden Observatory

   Affiliation as printed

   Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands

   Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, the Netherlands

8. T. W. Shimwell Aachen Leiden Observatory

   Leiden University · Leiden Observatory · Netherlands Institute for Radio Astronomy

   Affiliation as printed

   ASTRON, the Netherlands Institute for Radio Astronomy, Postbus 2, 7990 AA Dwingeloo, The Netherlands

   Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands

9. Cyril Tasse

   Centre National de la Recherche Scientifique · Rhodes University · Observatoire de Paris · Galaxies, Etoiles, Physique et Instrumentation · Université Paris Diderot

   Affiliation as printed

   Centre for Radio Astronomy Techniques and Technologies, Department of Physics and Electronics, Rhodes University, Grahamstown 6140, South Africa

   GEPI & USN, Observatoire de Paris, CNRS, Université Paris Diderot, 5 place Jules Janssen, 92190 Meudon, France

   GEPI & USN, Observatoire de Paris, CNRS Université Paris Diderot, 5 place Jules Janssen, 92190 Meudon, France