This article was accepted into the corpus but its outbound wikilinks were never NER-processed — typical at the deepest BFS hop or when the run's entity cap was reached. No expansion funnel to show.
| eMERLIN | |
|---|---|
| Name | eMERLIN |
| Caption | eMERLIN radio telescope array |
| Location | Jodrell Bank Observatory, Cheshire, England |
| Established | 2010–2012 upgrade |
| Owner | Science and Technology Facilities Council |
| Operator | University of Manchester |
| Type | Radio interferometer |
| Baseline | ~217 km |
| Frequency | 1.3–22 GHz |
| Resolution | milliarcsecond |
eMERLIN is a UK-based radio interferometer array providing high-resolution imaging and spectroscopy at centimetre wavelengths. It links several radio dishes across England to produce angular resolution comparable to international very-long-baseline facilities, enabling studies of compact sources related to Black hole, Active galactic nucleus, Star formation, and transient phenomena. The facility is operated by the University of Manchester within the framework of national and international collaborations.
eMERLIN is an enhanced successor to the MERLIN array, integrating upgraded receivers, high-bandwidth optical fiber, and a new correlator to connect antennas at Jodrell Bank Observatory, Pickmere, Defford, Cambridge, Darnhall, Knockin, and Mark II near Jodrell Bank Observatory. The array provides baselines up to ~217 km, delivering resolutions rivalling the Very Long Baseline Array and complementary coverage to the Karl G. Jansky Very Large Array, Atacama Large Millimeter/submillimeter Array, and European VLBI Network. eMERLIN supports continuum and spectral-line modes across bands overlapping with the 21 cm line, enabling joint programmes with facilities such as Square Kilometre Array, LOFAR, GMRT, MeerKAT, and ALMA.
The upgrade programme began as a national strategic investment involving the Science and Technology Facilities Council, the University of Manchester, and stakeholders from UK astronomy. The project modernised legacy hardware from the original MERLIN network, integrating optical fiber links similar to those used by the Square Kilometre Array pathfinders. Construction phases referenced international milestones such as the commissioning of the Very Large Array upgrades and the establishment of the European VLBI Network science operations. Technical leadership engaged engineers with backgrounds from projects like JIVE, Arecibo Observatory, and Jodrell Bank Centre for Astrophysics collaborations. Funding drew on national research councils and partnership agreements with observatories including Cambridge Observatory, University of Cambridge, and industrial contractors experienced in radio frequency and antenna engineering.
The eMERLIN array comprises seven principal antennas sited at historic facilities: the Lovell Telescope, Mk II, Darnhall, Knockin, Pickmere, Defford, and the Cambridge Radio Astronomy Observatory dish. Receivers span L-band, C-band, and K-band, facilitating observations of the HI line, OH megamaser transitions, and continuum emission from Synchrotron radiation sources associated with Supernova remnants, Pulsar, and Protostar environments. A high-capacity correlator synthesises signals using methods compatible with standards developed at JIVE, enabling interferometry modes that interoperate with the European VLBI Network and allow phasing-up for global arrays. The array's baselines provide uv-coverage tailored for imaging of Active galactic nucleus jets, gravitational lens systems studied alongside Hubble Space Telescope imaging, and radio counterparts to Chandra X-ray Observatory sources.
eMERLIN targets a range of astrophysical objectives: resolving parsec-scale jets in Radio galaxy and Quasar cores, mapping Starburst galaxy compact regions, tracing neutral hydrogen in nearby Galaxy disks, and monitoring radio transients including Gamma-ray burst afterglows and Tidal disruption event radio flares. Key programmes have linked eMERLIN observations with surveys from Sloan Digital Sky Survey, Pan-STARRS, Gaia, Spitzer Space Telescope, and Herschel Space Observatory to study multiwavelength counterparts. Projects include precision astrometry of Pulsar proper motions, imaging of Protoplanetary disk substructure in collaboration with ALMA, and investigations of Masers in high-mass star-forming regions studied in conjunction with VLBI networks.
Observing modes utilize phase-referencing, wideband continuum synthesis, and spectral-line Doppler tracking for the 21 cm line and molecular transitions. eMERLIN employs real-time fringe monitoring, fringe-fitting algorithms developed in parallel with software from CASA, AIPS, and data reduction pipelines influenced by workflows at NRAO and JIVE. Calibration strategies incorporate flux density standards such as sources monitored by VLA campaigns and astrometric ties to International Celestial Reference Frame. Data transport leverages optical fiber and high-speed networks similar to infrastructures used by GÉANT and research computing facilities at the University of Manchester and national supercomputing centres.
eMERLIN has delivered high-impact results: resolving compact radio cores in nearby Seyfert galaxy nuclei, imaging jet collimation regions in sources analogous to M87, detecting compact emission in Ultraluminous infrared galaxy mergers, and mapping HI absorption against background radio sources to probe Circumnuclear disk kinematics. The array contributed to transient follow-up programmes of GRB 030329-like events, provided astrometric constraints on Pulsar velocities, and characterized compact radio counterparts to Tidal disruption event candidates. Comparative studies with Hubble Space Telescope and Chandra X-ray Observatory datasets have refined models of feedback in Starburst galaxy systems and the interaction of Active galactic nucleus jets with interstellar media.
Operations are coordinated by the University of Manchester with strategic oversight from the Science and Technology Facilities Council and science users drawn from institutions including University of Cambridge, University of Oxford, Imperial College London, Cardiff University, University of Edinburgh, University of Glasgow, Durham University, University of Southampton, STFC Rutherford Appleton Laboratory, and international partners in the European VLBI Network. Time allocation follows peer-review processes similar to those at NRAO and ESO, and eMERLIN supports student training, visiting scientist programmes, and joint proposals with facilities such as ALMA, VLA, and MeerKAT. The facility contributes to UK involvement in global initiatives including the Square Kilometre Array and hosts workshops tied to observatories like Jodrell Bank Observatory and research consortia such as SEPNet.
Category:Radio telescopes Category:Interferometry Category:Astronomical observatories in England