Multiwavelength study of the radio emission from a tight galaxy pair Arp 143

作者：Nikiel Wroczynski B^*; Jamrozy M; Soida M; Urbanik M

来源：Monthly Notices of the Royal Astronomical Society, 2014, 444(2): 1729-1737.

DOI：10.1093/mnras/stu1475

• magnetic fields
• galaxies: groups: individual: Arp 143
• galaxies: individual: NGC 2445
• galaxies: interactions
• intergalactic medium
• radio continuum: galaxies

We present results of the recent low-frequency radio observations of a tight galaxy pair Arp 143 at 234 and 612 MHz. These data are analysed together with the archive data at 1490, 4860, 8440, and 14940 MHz. From the analysis of the radio emission we derive constraints on the age of the radio emitting structures as well as on the properties of their magnetic field. We show that the collisional ring of NGC 2445 hosts strong magnetic fields (reaching 12 mu G in its northwestern part) manifesting as a steep-spectrum, non-thermal radiation at radio frequencies. The spectral age of this structure is higher than estimates derived for the star-forming regions from the Ha distribution, suggesting that the radio emission might have a different origin. The galactic core is of a very young spectral age, suggesting an ongoing starburst activity. Additionally, we identify a possible ridge of emission between the ring galaxy and its elliptical companion NGC 2444.

• 出版日期2014-10-21