English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

We present the first maps of NGC 3044 and NGC 4157 at $\lambda\,450 \mu$m and$\lambda\,850 \mu$m from the JCMT as well as the first maps at 617 MHz from theGMRT. High latitude emission has been detected in both the radio continuum andsub-mm for NGC 3044 and in the radio continuum for NGC 4157, including severalnew features. The dust spectrum at long wavelengths required fitting with atwo-temperature model for both galaxies, implying the presence of cold dust.Dust masses are $M_d\,=\,1.6\,\times\,10^8 M_\odot$ and$M_d\,=\,2.1\,\times\,10^7 M_\odot$ for NGC 3044 and NGC 4157, respectively,and are dominated by the cold component. There is a clear correlation betweenthe 617 MHz and $\lambda\,850 \mu$m emission in the two galaxies. In the caseof NGC 3044, this implies a relation between the non-thermal synchrotronemission and cold dust. The 617 MHz component represents an integration ofmassive star formation over the past $10^{7-8}$ yr and the $\lambda \,850 \mu$memission represents heating from the diffuse interstellar radiation field(ISRF). The 617 MHz -- $\lambda\,850 \mu$m correlation improves when asmoothing kernel is applied to the $\lambda\,850 \mu$m data to account fordifferences between the CR electron diffusion scale and the mean free path ofan ISRF photon to dust. The best-fit relation is $L_{617_{\rmMHz}}\,\propto\,{L_{850 \mu{\rm m}}}^{2.1\,\pm\,0.2}$ for NGC 3044. Ifvariations in the cold dust emissivity are dominated by variations in dustdensity, and the synchrotron emission depends on magnetic field strength (afunction of gas density) as well as CR electron generation (a function ofmassive star formation rate and therefore density via the Schmidt law) then theexpected correlation for NGC 3044 is $L_{617_{\rm MHz}}\,\propto\,{L_{850\mu{\rm m}}}^{2.2}$, in agreement with the observed correlation.

The 617 MHz - $\lambda$ 850 $\mu$m Correlation (Cosmic Rays and Cold Dust) in NGC 3044 and NGC 4157