What sounds like a stomach-turning ride at an amusement park might hold the key to unravelling the mysterious mechanism that causes beams of radio waves to shoot out from pulsars -- super-magnetic rotating stars in our Galaxy.
New research from Curtin University, obtained using the Murchison Widefield Array (MWA) radio telescope located in the Western Australian outback, suggests the answer could lie in a 'drifting carousel' found in a special class of pulsars.
Curtin PhD student Sam McSweeney, who led the research as part of his PhD project with the ARC Centre of Excellence for All-sky Astrophysics (CAASTRO) and the International Centre for Radio Astronomy Research (ICRAR), described pulsars as extremely dense neutron stars that emit beams of radio waves.
"These pulsars weigh about half a million times the mass of the Earth but are only 20km across," Mr McSweeney said.
"They are nicknamed 'lighthouses in space' because they appear to 'pulse' once per rotation period, and their sweeping light signal can be seen through telescopes at exceptionally regular intervals."
Thousands of pulsars have been seen since their first discovery in the late 1960s, but questions still remain as to why these stars emit radio beams in the first place, and what type of emission model best describes the radio waves, or 'light', that we see.
"The classical pulsar model pictures the emission that is shooting out from the magnetic poles of the pulsar as a light cone," Mr McSweeney said.
"But the signal that we observe with our telescopes suggests a much more complex structure behind this emission - probably coming from several emission regions, not just one."
The 'drifting carousel' model manages to explain this complexity much better, describing the emission as coming from patches of charged particles, arranged in a rotating ring around magnetic field lines, or a carousel.
"As each patch releases radiation, the rotation generates a small drift in the observed signal of these sub-pulses that we can detect using the MWA," Mr McSweeney said.
"Occasionally, we find that this sub-pulse carousel gets faster and then slower again, which can be our best window into the plasma physics underlying the pulsar emission."
One possibility the researchers are currently testing is that surface temperature is responsible for the carousel changing rotation speed: localised 'hotspots' on the pulsar surface might cause it to speed up.
"We will observe individual pulses from these drifting pulsars across a wide range of radio frequencies, with lower frequency data than ever before," Mr McSweeney said.
"Looking at the same pulsar with different telescopes simultaneously will allow us to trace the emission at different heights above their surface."
The researchers plan to combine the data from the MWA, the Giant Metre-wave Radio Telescope in India and the CSIRO Parkes Radio Telescope in New South Wales to - literally - get to the bottom of the mysterious pulses.
###
A paper explaining the research, Low Frequency Observations of the Subpulse Drifter PSR J0034-0721 with the Murchison Widefield Array, was recently published in The Astrophysical Journal. An explanatory video is available under: https:/
Dr. Wiebke Ebeling | EurekAlert!
Further reports about: > Telescope > Telescopes > complex structure > magnetic field > neutron stars > plasma physics > pulsars > radio frequencies > radio waves > surface temperature
Fusion by strong lasers
06.12.2019 | Helmholtz-Zentrum Dresden-Rossendorf
NASA's OSIRIS-REx mission explains Bennu's mysterious particle events
06.12.2019 | NASA/Goddard Space Flight Center
University of Texas and MIT researchers create virtual UAVs that can predict vehicle health, enable autonomous decision-making
In the not too distant future, we can expect to see our skies filled with unmanned aerial vehicles (UAVs) delivering packages, maybe even people, from location...
With ultracold chemistry, researchers get a first look at exactly what happens during a chemical reaction
The coldest chemical reaction in the known universe took place in what appears to be a chaotic mess of lasers. The appearance deceives: Deep within that...
Abnormal scarring is a serious threat resulting in non-healing chronic wounds or fibrosis. Scars form when fibroblasts, a type of cell of connective tissue, reach wounded skin and deposit plugs of extracellular matrix. Until today, the question about the exact anatomical origin of these fibroblasts has not been answered. In order to find potential ways of influencing the scarring process, the team of Dr. Yuval Rinkevich, Group Leader for Regenerative Biology at the Institute of Lung Biology and Disease at Helmholtz Zentrum München, aimed to finally find an answer. As it was already known that all scars derive from a fibroblast lineage expressing the Engrailed-1 gene - a lineage not only present in skin, but also in fascia - the researchers intentionally tried to understand whether or not fascia might be the origin of fibroblasts.
Fibroblasts kit - ready to heal wounds
Research from a leading international expert on the health of the Great Lakes suggests that the growing intensity and scale of pollution from plastics poses serious risks to human health and will continue to have profound consequences on the ecosystem.
In an article published this month in the Journal of Waste Resources and Recycling, Gail Krantzberg, a professor in the Booth School of Engineering Practice...
Anzeige
Anzeige
03.12.2019 | Event News
First International Conference on Agrophotovoltaics in August 2020
15.11.2019 | Event News
Laser Symposium on Electromobility in Aachen: trends for the mobility revolution
15.11.2019 | Event News
Solving the mystery of carbon on ocean floor
06.12.2019 | Earth Sciences
Chip-based optical sensor detects cancer biomarker in urine
06.12.2019 | Life Sciences
A platform for stable quantum computing, a playground for exotic physics
06.12.2019 | Information Technology