e-MERLIN / VLBI National Radio Astronomy Facility

e-MERLIN science Legacy programme

The e-MERLIN Legacy programme

eΠ: e-MERLIN Pulsar Interferometry project

Principle Investigator:
Wouter Vlemmings (Argelander institute for Astronomy, Bonn, Germany) & Ben Stappers (University of Manchester, UK),

Time Allocation: 160 hours*

Co-Investigators include:-
Michael Kramer (University of Manchester, UK), Joseph Lazio (NRL, USA), Shami Chatterjee (The University of Sydney, Australia) Walter Brisken (NRAO, USA), Miller Goss (NRAO, USA), Bob Campbell (JIVE, The Netherlands), Huib Jan van Langevelde (JIVE/Leiden Observatory, The Netherlands), Matthew Bailes (Swinburne University, Austrlia), Adam Deller (Swinburne University, Austrlia), Don Backer (UC Berkeley, USA)


We propose an e-MERLIN Legacy Programme aimed at studying the physics of neutron star formation during supernovae and improving our understanding of Galactic structure. We will accomplish this with an astrometric program on radio pulsars with the goal of more than doubling the number of pulsars with accurate distances and velocities.Model independent velocities will place strong constraints on the mechanism responsible for the "kick" that is often imparted during the supernova in which the neutron star is formed and that makes the velocity of neutron stars the highest of any other class of stars. Such constraints are essential for probing the laws of physics at the extreme conditions that occur during supernova core-collapse. The astrometric observations will not only give the magnitude of the pulsar velocity, but also the direction that can be compared with the orientation of the spin-axis, pulsar wind nebulae and X-ray tori.

In many other aspects of the astrophysics and physics which can be probed with pulsars our understanding is enhanced by being able to derive accurate distances and velocities for them. Pulsars with known distance provide essential calibration points of the Galactic electron density structure models which in turn will improve distance estimates to pulsars without accurate astrometric data. Combined with observations of thermal radiation from the pulsar surface, distance measurements will constrain neutron star sizes with important implications for the neutron star equations of state. Knowing the proper motions also allows us to determine the birth locations of young pulsars and thus potentially associate them with the supernova remnants in which they were born and again allow us to study the physics of their birth. Moreover improved tests of theories of gravity and/or measuring the masses of neutron stars in binaries are also possible once we know the distance to a pulsar.

Team Web page, Full proposals (pdf)

*Additional time may be allocated subject to interim reviews throughout the course of this project.