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Meerkat and SKA are brainchild of a good old friend. So paying homage to his forsight in 1989 that saw it come to light.
www.sciencetimes.com
MeerKat Radio Telescope Discovers Eight New Millisecond Pulsars, Most Compact Stars Known
Tiziana Celine Apr 28, 2021 09:15 PM EDT
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Using the South African MeerKAT radio telescope, a team of astronomers found eight millisecond pulsars in globular clusters with high star density. Millisecond pulsars are neutron stars, the densest known stars that rotate up to 700 times per second around their axis. The findings are based on research conducted at the MeerKAT telescope by two international collaborations, TRAPUM and MeerTIME.
Millisecond pulsars are incredibly compact stars made up of neutrons that are among the universe's most remarkable artifacts. They pack hundreds of thousands of times the mass of the earth into a sphere with a diameter of around 24 km. These usually spin at hundreds of revolutions per second around their axis.
(Photo : Wikimedia Commons)
MeerKAT Radio Telescope
Like a lighthouse beacon, they emit a pulse of radio waves that streaks the observer with each rotation. High star density conditions in the centers of globular clusters favor the creation of these objects.
Experts uploaded their study entitled "Eight New Millisecond Pulsars From the First Meerkat Globular Cluster Census," at the monthly notices of the Royal Astronomical Society.
How Experts Discovered the New Pulsars
First author Alessandro Ridolfi said in a statement that they aligned the sea-kat antennas at nine globular clusters and discovered new pulsars in six of them. Ridofil works as a post-doc at the Italian National Institute of Astrophysics (INAF) and the Max Planck Institute for Radio Astronomy (MPIfR).
Each of the five new pulsars orbits a different star, with PSR J1823-3021G proving to be especially important.
Tasha Gautam, a PhD student at the MPIfR in Bonn and a co-author of the paper, clarified that this pulsar might have a large mass, more than twice that of the sun.
Still, it could also be the first confirmed system containing a millisecond pulsar and a neutron star. If the latest additional observations support this, Gautam believes this millisecond pulsar would be an excellent test ground for new fundamental physics insights.
ALSO READ: South Africa's MeerKAT Telescope Discovered Two Giant Radio Galaxies
Latest Discovery Just Tip of the Iceberg
The eight new pulsars are just the tip of the iceberg in terms of discoveries.
About 40 of the 64 MeerKAT antennas were used in the observations that led to their discovery, Phys.org said. They were only based on the central regions of globular clusters.
MeerKAT is expected to discover hundreds of new millisecond pulsars over the next few years, experts said. It will give us a glimpse of what will be possible once the SKA Observatory's mid-frequency antennas are fully operational. They went on to say that this would change many aspects of astrophysics, including the study of pulsars.
Ridolfi, Gautam, and Possenti are part of the TRAnsients and PUlsars with MeerKAT (TRAPUM) collaboration. It's a large study for MeerKAT with an extensive international collaboration of astronomers who are enthusiastic about the possibilities that MeerKAT provides. They shared telescope time for this project to research already known pulsars with unprecedented precision.
This study acted as a model experiment for the TRAPUM collaboration to better prepare a full-fledged globular cluster survey to find new pulsars.
Further Studies Underway
Using all 64 parabolic levels from MeerKAT, such sampling is currently underway (further increasing sensitivity). It will broaden the quest to include a larger number of globular clusters and quantify their outer regions.
Experts claim that many bizarre and intense double pulsars have already been discovered in previous search programs for pulsars in globular clusters.
We will undoubtedly be able to discover more of these extreme structures with new instruments like MeerKAT, which will reveal more about the fundamental laws of our universe "Paulo Freire, another co-author of THE MPIfR, sums it up.
A New Window to See Unexplored Hidden Side of Magnetized Universe
TOPICS:AstronomyAstrophysicsNational Institutes Of Natural SciencesPopular
By NATIONAL INSTITUTES OF NATURAL SCIENCES MAY 10, 2021
The bent jet structures emitted from MRC 0600-399 as observed by the MeerKAT radio telescope (left) are well reproduced by the simulation conducted on ATERUI II (right). The nearby galaxy B visible in the left part of the MeerKAT image is not affecting the jet and has been excluded in the simulation. Credit: Chibueze, Sakemi, Ohmura et al. (MeerKAT image); Takumi Ohmura, Mami Machida, Hirotaka Nakayama, 4D2U Project, NAOJ (ATERUI II image))
New observations and simulations show that jets of high-energy particles emitted from the central massive black hole in the brightest galaxy in galaxy clusters can be used to map the structure of invisible inter-cluster magnetic fields. These findings provide astronomers with a new tool for investigating previously unexplored aspects of clusters of galaxies.
As clusters of galaxies grow through collisions with surrounding matter, they create bow shocks and wakes in their dilute plasma. The plasma motion induced by these activities can drape intra-cluster magnetic layers, forming virtual walls of magnetic force. These magnetic layers, however, can only be observed indirectly when something interacts with them. Because it is simply difficult to identify such interactions, the nature of intra-cluster magnetic fields remains poorly understood. A new approach to map/characterize magnetic layers is highly desired.
Simulation of the Interaction Between a Jet and the Magnetic Field of a Galaxy Cluster. Movie of the interaction between a jet and the magnetic field of a galaxy cluster, as simulated by ATERUI II. The color of the jet represents the velocity of the gas. The higher velocity part of the jet is shown in orange, and the slower part is shown in blue. The yellow lines represent the magnetic field lines. In the last scene, the intensity of electromagnetic radiation predicted by the simulation is shown in yellow. Credit: Takumi Ohmura, Mami Machida, Hirotaka Nakayama, 4D2U Project, NAOJ
An international team of astronomers including Haruka Sakemi, a graduate student at Kyushu University (now a research fellow at the National Astronomical Observatory of Japan – NAOJ), used the MeerKAT radio telescope located in the Northern Karoo desert of South Africa to observe a bright galaxy in the merging galaxy cluster Abell 3376 known as MRC 0600-399. Located more than 600 million light-years away in the direction of the constellation Columba, MRC 0600-399 is known to have unusual jet structures bent to 90-degree angles. Previous X-ray observations revealed that MRC 0600-399 is the core of a sub-cluster penetrating the main cluster of galaxies, indicating the presence of strong magnetic layers at the boundary between the main and sub-clusters. These features make MRC 0600-399 an ideal laboratory to investigate interactions between jets and strong magnetic layers.
The MeerKAT observations revealed unprecedented details of the jets, most strikingly, faint “double-scythe” structure extending in the opposite direction from the bend points and creating a “T” shape. These new details show that, like a stream of water hitting a pane of glass, this is a very chaotic collision. Dedicated computer simulations are required to explain the observed jet morphology and possible magnetic field configurations.
Takumi Ohmura, a graduate student at Kyushu University (now a research fellow at the University of Tokyo’s Institute for Cosmic-Ray Research – ICRR), from the team performed simulations on NAOJ’s supercomputer ATERUI II, the most powerful computer in the world dedicated to astronomical calculations. The simulations assumed an arch-like strong magnetic field, neglecting messy details like turbulence and the motion of the galaxy.
This simple model provides a good match to the observations, indicating that the magnetic pattern used in the simulation reflects the actual magnetic field intensity and structure around MRC 0600-399. More importantly, it demonstrates that the simulations can successfully represent the underlying physics so that they can be used on other objects to characterize more complex magnetic field structures in clusters of galaxies. This provides astronomers with a new way to understand the magnetized Universe and a tool to analyze the higher-quality data from future radio observatories like the SKA (the Square Kilometer Array).
Reference: “Jets from MRC 0600-399 bent by magnetic fields in the cluster Abell 3376” by James O. Chibueze, Haruka Sakemi, Takumi Ohmura, Mami Machida, Hiroki Akamatsu, Takuya Akahori, Hiroyuki Nakanishi, Viral Parekh, Ruby van Rooyen and Tsutomu T. Takeuchi, 5 May 2021, Nature.
DOI: 10.1038/s41586-021-03434-1
What Exactly Is The Mystery Behind These Odd 'X-Galaxies?'
www.wkyc.com
If anyone knows of anyone wanting to join this research work:
They are accepting candidates in astrophysics related research.
www.sarao.ac.za
SARAO Scholarships and Postdoctoral Fellowships
Guide to Calls for Scholarship and Postdoctoral Fellowships for 2022
Successful applicants will be notified in writing by 30 November 2021
SARAO Postdoctoral Fellowships for 2022
Call opens on: TBC
Application Guide
Apply at: https://nrfsubmission.nrf.ac.za/nrfmkii/
For more information contact:
Annah Mashemola
amashemola@ska.ac.za
011 268 3420
SARAO Doctoral Scholarships for 2022
Call opens on: 1 April 2021
Application Guide
Approved Doctoral Research Projects – 2022
Apply at: https://nrfsubmission.nrf.ac.za/nrfmkii/
For more information contact:
Annah Mashemola
amashemola@ska.ac.za
011 268 3420
SARAO Masters Scholarships for 2022
Call opens on: 1 April 2021
Application Guide
Approved Masters Research Projects – 2022
Apply at: https://nrfsubmission.nrf.ac.za/nrfmkii/
For more information contact:
Annah Mashemola
amashemola@ska.ac.za
011 268 3420
SARAO Honours Scholarships for 2022
Call opens on: 1 April 2021
Application Guide
Apply at: https://nrfsubmission.nrf.ac.za/nrfmkii/
For more information contact:
Annah Mashemola
amashemola@ska.ac.za
011 268 3420
SARAO Undergraduate Scholarships for 2022
Call opens on: TBC
Application Guide
Apply at: https://nrfsubmission.nrf.ac.za/nrfmkii/
For more information contact:
Annah Mashemola
amashemola@ska.ac.za
011 268 3420
SARAO Diploma in Engineering Technology Scholarships for 2022
Call opens on: TBC
Application Guide
Apply at: https://nrfsubmission.nrf.ac.za/nrfmkii/
For more information contact:
Annah Mashemola
amashemola@ska.ac.za
011 268 3420
SARAO Bachelor of Engineering Technology Scholarships for 2022
Call opens on: TBC
Application Guide
Apply at: https://nrfsubmission.nrf.ac.za/nrfmkii/
For more information contact:
Annah Mashemola
amashemola@ska.ac.za
011 268 3420
MeerKat Radio Telescope Discovers Eight New Millisecond Pulsars, Most Compact Stars Known
Scientists made an astonishing find in the universe after the MeerKAT telescope of South Africa discovered eight new millisecond pulsars.
www.sciencetimes.com
MeerKat Radio Telescope Discovers Eight New Millisecond Pulsars, Most Compact Stars Known
Tiziana Celine Apr 28, 2021 09:15 PM EDT
FacebookTwitterLinkedinCommentMail
Close
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Current Time0:05
Duration Time0:15
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Using the South African MeerKAT radio telescope, a team of astronomers found eight millisecond pulsars in globular clusters with high star density. Millisecond pulsars are neutron stars, the densest known stars that rotate up to 700 times per second around their axis. The findings are based on research conducted at the MeerKAT telescope by two international collaborations, TRAPUM and MeerTIME.
Millisecond pulsars are incredibly compact stars made up of neutrons that are among the universe's most remarkable artifacts. They pack hundreds of thousands of times the mass of the earth into a sphere with a diameter of around 24 km. These usually spin at hundreds of revolutions per second around their axis.
(Photo : Wikimedia Commons)
MeerKAT Radio Telescope
Like a lighthouse beacon, they emit a pulse of radio waves that streaks the observer with each rotation. High star density conditions in the centers of globular clusters favor the creation of these objects.
Experts uploaded their study entitled "Eight New Millisecond Pulsars From the First Meerkat Globular Cluster Census," at the monthly notices of the Royal Astronomical Society.
How Experts Discovered the New Pulsars
First author Alessandro Ridolfi said in a statement that they aligned the sea-kat antennas at nine globular clusters and discovered new pulsars in six of them. Ridofil works as a post-doc at the Italian National Institute of Astrophysics (INAF) and the Max Planck Institute for Radio Astronomy (MPIfR).
Each of the five new pulsars orbits a different star, with PSR J1823-3021G proving to be especially important.
Tasha Gautam, a PhD student at the MPIfR in Bonn and a co-author of the paper, clarified that this pulsar might have a large mass, more than twice that of the sun.
Still, it could also be the first confirmed system containing a millisecond pulsar and a neutron star. If the latest additional observations support this, Gautam believes this millisecond pulsar would be an excellent test ground for new fundamental physics insights.
ALSO READ: South Africa's MeerKAT Telescope Discovered Two Giant Radio Galaxies
Latest Discovery Just Tip of the Iceberg
The eight new pulsars are just the tip of the iceberg in terms of discoveries.
About 40 of the 64 MeerKAT antennas were used in the observations that led to their discovery, Phys.org said. They were only based on the central regions of globular clusters.
MeerKAT is expected to discover hundreds of new millisecond pulsars over the next few years, experts said. It will give us a glimpse of what will be possible once the SKA Observatory's mid-frequency antennas are fully operational. They went on to say that this would change many aspects of astrophysics, including the study of pulsars.
Ridolfi, Gautam, and Possenti are part of the TRAnsients and PUlsars with MeerKAT (TRAPUM) collaboration. It's a large study for MeerKAT with an extensive international collaboration of astronomers who are enthusiastic about the possibilities that MeerKAT provides. They shared telescope time for this project to research already known pulsars with unprecedented precision.
This study acted as a model experiment for the TRAPUM collaboration to better prepare a full-fledged globular cluster survey to find new pulsars.
Further Studies Underway
Using all 64 parabolic levels from MeerKAT, such sampling is currently underway (further increasing sensitivity). It will broaden the quest to include a larger number of globular clusters and quantify their outer regions.
Experts claim that many bizarre and intense double pulsars have already been discovered in previous search programs for pulsars in globular clusters.
We will undoubtedly be able to discover more of these extreme structures with new instruments like MeerKAT, which will reveal more about the fundamental laws of our universe "Paulo Freire, another co-author of THE MPIfR, sums it up.
A New Window to See Unexplored Hidden Side of Magnetized Universe
New observations and simulations show that jets of high-energy particles emitted from the central massive black hole in the brightest galaxy in galaxy clusters can be used to map the structure of invisible inter-cluster magnetic fields. These findings provide astronomers with a new tool for investig
scitechdaily.com
A New Window to See Unexplored Hidden Side of Magnetized Universe
TOPICS:AstronomyAstrophysicsNational Institutes Of Natural SciencesPopular
By NATIONAL INSTITUTES OF NATURAL SCIENCES MAY 10, 2021
The bent jet structures emitted from MRC 0600-399 as observed by the MeerKAT radio telescope (left) are well reproduced by the simulation conducted on ATERUI II (right). The nearby galaxy B visible in the left part of the MeerKAT image is not affecting the jet and has been excluded in the simulation. Credit: Chibueze, Sakemi, Ohmura et al. (MeerKAT image); Takumi Ohmura, Mami Machida, Hirotaka Nakayama, 4D2U Project, NAOJ (ATERUI II image))
New observations and simulations show that jets of high-energy particles emitted from the central massive black hole in the brightest galaxy in galaxy clusters can be used to map the structure of invisible inter-cluster magnetic fields. These findings provide astronomers with a new tool for investigating previously unexplored aspects of clusters of galaxies.
As clusters of galaxies grow through collisions with surrounding matter, they create bow shocks and wakes in their dilute plasma. The plasma motion induced by these activities can drape intra-cluster magnetic layers, forming virtual walls of magnetic force. These magnetic layers, however, can only be observed indirectly when something interacts with them. Because it is simply difficult to identify such interactions, the nature of intra-cluster magnetic fields remains poorly understood. A new approach to map/characterize magnetic layers is highly desired.
Simulation of the Interaction Between a Jet and the Magnetic Field of a Galaxy Cluster. Movie of the interaction between a jet and the magnetic field of a galaxy cluster, as simulated by ATERUI II. The color of the jet represents the velocity of the gas. The higher velocity part of the jet is shown in orange, and the slower part is shown in blue. The yellow lines represent the magnetic field lines. In the last scene, the intensity of electromagnetic radiation predicted by the simulation is shown in yellow. Credit: Takumi Ohmura, Mami Machida, Hirotaka Nakayama, 4D2U Project, NAOJ
An international team of astronomers including Haruka Sakemi, a graduate student at Kyushu University (now a research fellow at the National Astronomical Observatory of Japan – NAOJ), used the MeerKAT radio telescope located in the Northern Karoo desert of South Africa to observe a bright galaxy in the merging galaxy cluster Abell 3376 known as MRC 0600-399. Located more than 600 million light-years away in the direction of the constellation Columba, MRC 0600-399 is known to have unusual jet structures bent to 90-degree angles. Previous X-ray observations revealed that MRC 0600-399 is the core of a sub-cluster penetrating the main cluster of galaxies, indicating the presence of strong magnetic layers at the boundary between the main and sub-clusters. These features make MRC 0600-399 an ideal laboratory to investigate interactions between jets and strong magnetic layers.
The MeerKAT observations revealed unprecedented details of the jets, most strikingly, faint “double-scythe” structure extending in the opposite direction from the bend points and creating a “T” shape. These new details show that, like a stream of water hitting a pane of glass, this is a very chaotic collision. Dedicated computer simulations are required to explain the observed jet morphology and possible magnetic field configurations.
Takumi Ohmura, a graduate student at Kyushu University (now a research fellow at the University of Tokyo’s Institute for Cosmic-Ray Research – ICRR), from the team performed simulations on NAOJ’s supercomputer ATERUI II, the most powerful computer in the world dedicated to astronomical calculations. The simulations assumed an arch-like strong magnetic field, neglecting messy details like turbulence and the motion of the galaxy.
This simple model provides a good match to the observations, indicating that the magnetic pattern used in the simulation reflects the actual magnetic field intensity and structure around MRC 0600-399. More importantly, it demonstrates that the simulations can successfully represent the underlying physics so that they can be used on other objects to characterize more complex magnetic field structures in clusters of galaxies. This provides astronomers with a new way to understand the magnetized Universe and a tool to analyze the higher-quality data from future radio observatories like the SKA (the Square Kilometer Array).
Reference: “Jets from MRC 0600-399 bent by magnetic fields in the cluster Abell 3376” by James O. Chibueze, Haruka Sakemi, Takumi Ohmura, Mami Machida, Hiroki Akamatsu, Takuya Akahori, Hiroyuki Nakanishi, Viral Parekh, Ruby van Rooyen and Tsutomu T. Takeuchi, 5 May 2021, Nature.
DOI: 10.1038/s41586-021-03434-1
What Exactly Is The Mystery Behind These Odd 'X-Galaxies?'
What Exactly Is The Mystery Behind These Odd 'X-Galaxies?'
Scientists have been scratching their heads at the mysterious shape of 'X-galaxies' for a while, but using the MeerKAT Telescope to observe one of these galaxies in unprecedented detail has helped them solve the longstanding mystery.
www.wkyc.com
They are accepting candidates in astrophysics related research.
Scholarships and Postdoctoral Fellowships - South African Radio Astronomy Observatory - SARAO
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www.sarao.ac.za
SARAO Scholarships and Postdoctoral Fellowships
Guide to Calls for Scholarship and Postdoctoral Fellowships for 2022
Successful applicants will be notified in writing by 30 November 2021
SARAO Postdoctoral Fellowships for 2022
Call opens on: TBC
Application Guide
Apply at: https://nrfsubmission.nrf.ac.za/nrfmkii/
For more information contact:
Annah Mashemola
amashemola@ska.ac.za
011 268 3420
SARAO Doctoral Scholarships for 2022
Call opens on: 1 April 2021
Application Guide
Approved Doctoral Research Projects – 2022
Apply at: https://nrfsubmission.nrf.ac.za/nrfmkii/
For more information contact:
Annah Mashemola
amashemola@ska.ac.za
011 268 3420
SARAO Masters Scholarships for 2022
Call opens on: 1 April 2021
Application Guide
Approved Masters Research Projects – 2022
Apply at: https://nrfsubmission.nrf.ac.za/nrfmkii/
For more information contact:
Annah Mashemola
amashemola@ska.ac.za
011 268 3420
SARAO Honours Scholarships for 2022
Call opens on: 1 April 2021
Application Guide
Apply at: https://nrfsubmission.nrf.ac.za/nrfmkii/
For more information contact:
Annah Mashemola
amashemola@ska.ac.za
011 268 3420
SARAO Undergraduate Scholarships for 2022
Call opens on: TBC
Application Guide
Apply at: https://nrfsubmission.nrf.ac.za/nrfmkii/
For more information contact:
Annah Mashemola
amashemola@ska.ac.za
011 268 3420
SARAO Diploma in Engineering Technology Scholarships for 2022
Call opens on: TBC
Application Guide
Apply at: https://nrfsubmission.nrf.ac.za/nrfmkii/
For more information contact:
Annah Mashemola
amashemola@ska.ac.za
011 268 3420
SARAO Bachelor of Engineering Technology Scholarships for 2022
Call opens on: TBC
Application Guide
Apply at: https://nrfsubmission.nrf.ac.za/nrfmkii/
For more information contact:
Annah Mashemola
amashemola@ska.ac.za
011 268 3420
