Welcome to the issue 3 of the e-
MERLIN newsletter. We will be
publishing e-MERLIN-related
news and science highlights,
including calls for proposals,
adverts for summer schools and
links to e-MERLIN partners like
the EVN and ORP. If you would
like to contribute to the e-MERLIN
newsletter, please get in touch at:
emerlin.support@jb.man.ac.uk !
Setting up for SETI
The Search for Extraterrestrial
Intelligence (SETI) has conducted
numerous searches for techno-
signatures for decades. However,
the use of long baseline arrays
such as e-MERLIN and EVN has
not been fully explored even
though the astrometry and
sensitivity allows you to localise
signals better with greater
robustness. Observations with
EVN + e-MERLIN serendipitously
detected a signal at 1420.4 MHz,
but this turned out to be due to
Galactic hydrogen in the beams
of the antennas while looking at
the exoplanet system
Kepler-111b. Never-the-less, this
work paves the way for future
SETI studies using VLBI. !
Read the full paper here (Wandia
et al. 2023, MNRAS, Volume 223,
Issue 3, pp 3784)!
e-MERLIN detects the Type 1a
supernova, SN2020eyj
Some stars die as Type 1a supernovae, where a
thermonuclear explosion of a white dwarf occurs due to
reaching the Chandrasekhar limit. However, the exact
evolutionary path of these systems is still unclear. Two
scenarios, the single degenerate (one white dwarf and a
companion star in a binary) and the double degenerate
(coalescence of two white dwarfs) have been proposed.
One observational piece of evidence that may support
the single degenerate scenario is the presence of radio
emission owing to interaction between the explosion
and the companion stars winds. !
e-MERLIN has detected radio emission for the first time
in any Type 1a supernova. This particular supernova, SN
2020eyj, showed evidence for circumstellar medium
interaction with helium lines evident in its optical
spectrum. The radio data were taken over 600 days
post explosion and future observations will identify what
is causing the radio emission.!
Read the full paper here (Kool et al. 2023, Nature,
Volume 617, Issue 7961, 477-482)!
User Newsletter
Issue 3 31 July 2023!
e-MERLIN detections and models for SN2020eyj