MeerTRAP Science Goals

We can advance the frontiers of physics by observations of the extremes. Fast radio transients, with timescales typically less than a second, are likely  associated with the extremes of energy, magnetic field strength, gravity and density. These sources provide a unique laboratory with which to probe physical  regimes well beyond those achievable in any terrestrial experiment. Located at extragalactic distances, they can be used as probes of the content of the  intergalactic medium (IGM) and the nature of the missing baryons. Moreover, if they can be shown to be standard candles, then they will be useful additional components of the distance ladder reaching out to redshifts up to 2 and perhaps beyond. We are only just scratching the surface in terms of our  understanding of the fast radio transient sky, and so we are also exploring the unknown. 

Detecting fast radio transients is extremely challenging; their sporadic nature requires either vast amounts of observing time and/or wider fields of view to catch them. The known sources already span a range of durations from nanoseconds, e.g. giant pulses from the Crab pulsar, to seconds, e.g the Galactic centre transient GCRT J1745-3009. Likewise the luminosity spans 20 orders of magnitude, from Jupiter emission to fast radio bursts (FRBs); however, the majority of the intervening parameter space is unexplored. Other known and proposed sources include: ultra-high-energy particles, annihilating black holes, merging neutron stars, supernovae and gamma-ray bursts, flare stars, planets (solar and extra-solar), neutron stars (intermittent pulsars/magnetars/RRATs), extra-terrestrial intelligence and things that have not yet even been thought of!

We can summarise the goals of MeerTRAP as being:

Goal 1: The bursting sky

• Detect hundreds of Galactic and extragalactic short duration radio bursts from extreme and cataclysmic environments to understand the associated physics
• Identify prompt radio emission potentially associated with events like gamma-ray bursts and gravitational wave emission
• Determine accurate positions of FRBs allowing us to distinguish formation models and use them as cosmological probes through their interaction with the IGM and space-time.

Goal 2: The periodic sky

Discover radio pulsars over an unprecedented range of parameter space by covering: variability on timescales from days to years, luminosity, spectral index, binarity, and multiple systems. This will give us the most comprehensive view yet of the radio emitting neutron star population with the implications this has for star formation history, binary evolution, and neutron star merger rates. It will reveal individual systems that can be used to test gravitational theories, probe the equation of state of ultra-dense matter, and enable the direct detection of nano-hertz gravitational waves.