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 Plus annual

Presents the access of premium content as premium feature

Premium Content

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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Emission from the radioactive trace element $^{26}$Al has been observedthroughout the Milky Way with the COMPTEL and INTEGRAL satellites. Inparticular the Doppler shifts measured with INTEGRAL connect $^{26}$Al withsuperbubbles, which may guide $^{26}$Al flows off spiral arms in the directionof Galactic rotation. In order to test this paradigm, we have performedgalaxy-scale simulations of superbubbles with $^{26}$Al injection in a MilkyWay-type galaxy. We produce all-sky synthetic $\gamma-$ray emission maps of thesimulated galaxies. We find that the 1809keV emission from the radioactivedecay of $^{26}$Al is highly variable with time and the observer's position.This allows us to estimate an additional systematic variability of 0.2dex for astar formation rate derived from $^{26}$Al for different times and measurementlocations in Milky Way-type galaxies. High-latitude morphological featuresindicate nearby emission with correspondingly high integrated $\gamma-$rayintensities. We demonstrate that the $^{26}$Al scale height from our simulatedgalaxies depends on the assumed halo gas density. We present the firstsynthetic 1809keV longitude-velocity diagrams from 3D hydrodynamic simulations.The line-of-sight velocities for $^{26}$Al can be significantly different fromthe line-of-sight velocities associated with the cold gas. Over time, $^{26}$Alvelocities consistent with the INTEGRAL observations, within uncertainties,appear at any given longitude, broadly supporting previous suggestions that$^{26}$Al injected into expanding superbubbles by massive stars may beresponsible for the high velocities found in the INTEGRAL observations. Wediscuss the effect of systematically varying the location of the superbubblesrelative to the spiral arms.

Synthetic $^{26}$Al emission from galactic-scale superbubble simulations