Welcome to the issue 4 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 !
First e-MERLIN Data
school held at JBCA
Last week at JBCA (23-25
October), we held the first e-
MERLIN data school. Participants
learnt about using the e-MERLIN
CASA Pipeline (eMCP) to
calibrate and image e-MERLIN
data. The ORP sponsored event
enabled students from across the
world to bring their own e-
MERLIN data to get expert help
from the in-house operations
team at Jodrell Bank.!
Missed the data school? We’ve
placed all of the documentation
online here. We will also be
holding similar events in the
future, including hybrid versions
so that more people can attend.
Please get in touch if you are
interested in in-person or hybrid
events such as this in the future.
e-MERLIN detections of oset dual-
SMBH candidates proves fruitful
Dual super massive black holes (SMBH) may appear in
the post-merger stage of galaxies and as the system
evolves the two SMBHs would get closer to each other
and coalesce. Such dual SMBHs may appear as a dual
AGN (active galactic nuclei) if both SMBHs are
accreting, or an o-nucleus AGN, if only one SMBH is
active. However dual and o-nucleus AGN were
previously found mostly at low redshifts or large
separations (> 10 kpc).!
One promising technique is that of varstrometry, which
uses the astrometric jitter of the photocenter in Gaia
observations to identify candidate dual AGNs. In this
study, five such sources were selected for e-MERLIN
follow-up and four of them showed significant radio-
optical osets, suggesting an oset radio-loud nucleus
and the optical photocenter of the dual SMBH system.
This large oset is not normally seen in quasars, further
favouring the dual or o-nucleus scenario. Thus, e-
MERLIN observations of such systems could be a
potentially fruitful probe of dual-SMBHs in the future.!
Read the full paper here (Wang et al. 2023, MNRAS
Letters, Volume 524, Issue 1, p.L38)!
User Newsletter
Issue 4 3 November 2023"
Radio-optical offsets of five dual-SMBH