Our research group is focused on computational and high-energy astrophysics of massive stars, including their evolution and explosion. Group members are engaged in theoretical calculations and computer simulations of nebulae around massive stars, to understand how stars evolve and impact the surrounding interstellar space. We also work with observations across the electromagnetic spectrum, including interferometric radio observations from LOFAR and the VLA, and we are members of the H.E.S.S. collaboration, measuring the highest energy gamma rays arriving on Earth. Combining computer simulations with observations can give new insights and constraints into the physics of stars and particle acceleration. We are also leading some “citizen science” projects at DIAS Dunsink Observatory and contributing strongly to the education and public engagement activities.
Hydrodynamic simulations of NGC 7635, the Bubble Nebula (Green et al., 2019).
High-Performance Computing
Modelling nebulae produced by the evolution and explosion of massive stars requires computer simulations because the non-linear fluid-dynamics equations cannot be solved analytically, and it takes hundreds of thousands of years for stars to evolve in real time. We can only see a small snapshot of evolution with telescopes/satellites, but with simulations we can model wind-driven nebulae for the whole lifetime of the star. We use both our in-house software PION and other fluid-dynamics and stellar-evolution packages for our research.Detailed calculations require High Performance Computing (HPC) infrastructure because simulations would take months to run on a regular laptop/PC, but with supercomputers they only take a few days. This allows us to run many simulations and explore the effects of different parameters and different physical processes. The Irish Centre for High-End Computing (ICHEC) operates the national HPC infrastructure for researchers to run their models/simulations, and we are using their main supercomputer Kay for our latest generation of 3D simulations.
Observations of Massive Stars, H.E.S.S. and the non-thermal Universe
Massive OB-type stars that have escaped their formation region plough their way through the interstellar medium with very high velocities (more than 30 km/s) and their strong winds (more than 1000 km/s) displace surrounding interstellar gas. This interaction compresses the interstellar matter into a bow-shaped shock wrapped around the star in its direction of motion, often observed in the infrared part of the electromagnetic spectrum, produced by glowing dust grains. The wind termination-shock can accelerate some of the wind ions and electrons up to relativistic speeds, and so the sources should emit both thermal and non-thermal emission. This non-thermal radiation has been detected in radio waves (Benaglia et al, 2010) with the Very Large Array (VLA, see image). We are using the VLA and LOFAR to observe and characterise these sources in combination with computer simulations.
The FERMI satellite detects high-energy gamma-rays at energies up to 300 GeV.
Large clusters of massive stars, by contrast, are well-known non-thermal emitters in X-rays and gamma-rays, and supernova remnants (debris from exploding stars) are known to be major production sites of high-energy cosmic rays in our Galaxy. The H.E.S.S. telescopes in Namibia and the FERMI Gamma-ray Space Telescope (see figures) have produced the most detailed maps of the high-energy Universe. Our group is part of the HESS collaboration and we are actively contributing to the analysis of the data on Galactic sources, to better understand the role of massive stars and their winds in particle acceleration. We also study Active Galactic Nuclei across the whole electromagnetic spectrum.
The Very Large Array (VLA) in New Mexico, USA, is operated by the NRAO and consists of 27 antennas with each having a 25-meter dish.
One year ago today... What a thrill to meet President Higgins and other @scienceirel awardees. Myself and my team have been working hard (from home) for the past year and we look forward to returning to in-person collaboration @DIASAstronomy in the not-too-distant future! twitter.com/PresidentIRL/s…Retweeted by
DIAS Astronomy & Astrophysics
Today marks the 'International day of Women and Girls in Science'. Below you can meet some DIAS's past and present women leading innovation and empowering women and girls across the world!
Our CEO Eucharia Meehan will be chatting with @HeritageHubIRE later today on this topic Retweeted by
DIAS Astronomy & Astrophysics
@albertocaniz91, a PhD student of Solar Physics at DIAS and Trinity College Dublin has also been part of the organising committee for our Astrophotography competition. In his free time Alberto is a very passionate photographer... (1/2) Retweeted by
DIAS Astronomy & Astrophysics
We're back!!! 🎉🎉🎉 Our first event of 2021 will be hosted online on Monday January 25th at 20:00 CET, streaming live on our YouTube channel! @ciara_a_maguire and @AstroJoeC will tell us all about radio stars! 📡✨ So grab a drink, get comfortable, and join us! Retweeted by
DIAS Astronomy & Astrophysics
Kicking of new links between @DIASAstronomy and @DCUPhysics @DCU_CFAR this morning. We’ll virtually be hosting eight 3rd year Physics & Astronomy students working on @I_LOFAR, SolarMonitor.org and FERMI for the next 3 months. Looking forward to working with new students! Retweeted by
DIAS Astronomy & Astrophysics
PhD Studentship now available to work with @cm_jackman on planetary magnetospheres! Application deadline 31 January. More information here: dias.ie/phd-planetary-… 🌞🪐
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Computational and High Energy Astrophysics
Group Leader: Dr Jonathan Mackey
Research Fellows: Dr Davit Zargaryan, Dr Robert Brose
Research Students: Sam Green, Maria Moutzouri
Publications: from the Astrophysics Data System
Our research group is focused on computational and high-energy astrophysics of massive stars, including their evolution and explosion. Group members are engaged in theoretical calculations and computer simulations of nebulae around massive stars, to understand how stars evolve and impact the surrounding interstellar space. We also work with observations across the electromagnetic spectrum, including interferometric radio observations from LOFAR and the VLA, and we are members of the H.E.S.S. collaboration, measuring the highest energy gamma rays arriving on Earth. Combining computer simulations with observations can give new insights and constraints into the physics of stars and particle acceleration. We are also leading some “citizen science” projects at DIAS Dunsink Observatory and contributing strongly to the education and public engagement activities.
High-Performance Computing
Modelling nebulae produced by the evolution and explosion of massive stars requires computer simulations because the non-linear fluid-dynamics equations cannot be solved analytically, and it takes hundreds of thousands of years for stars to evolve in real time. We can only see a small snapshot of evolution with telescopes/satellites, but with simulations we can model wind-driven nebulae for the whole lifetime of the star. We use both our in-house software PION and other fluid-dynamics and stellar-evolution packages for our research.Detailed calculations require High Performance Computing (HPC) infrastructure because simulations would take months to run on a regular laptop/PC, but with supercomputers they only take a few days. This allows us to run many simulations and explore the effects of different parameters and different physical processes. The Irish Centre for High-End Computing (ICHEC) operates the national HPC infrastructure for researchers to run their models/simulations, and we are using their main supercomputer Kay for our latest generation of 3D simulations.
Observations of Massive Stars, H.E.S.S. and the non-thermal Universe
Massive OB-type stars that have escaped their formation region plough their way through the interstellar medium with very high velocities (more than 30 km/s) and their strong winds (more than 1000 km/s) displace surrounding interstellar gas. This interaction compresses the interstellar matter into a bow-shaped shock wrapped around the star in its direction of motion, often observed in the infrared part of the electromagnetic spectrum, produced by glowing dust grains. The wind termination-shock can accelerate some of the wind ions and electrons up to relativistic speeds, and so the sources should emit both thermal and non-thermal emission. This non-thermal radiation has been detected in radio waves (Benaglia et al, 2010) with the Very Large Array (VLA, see image). We are using the VLA and LOFAR to observe and characterise these sources in combination with computer simulations.
Large clusters of massive stars, by contrast, are well-known non-thermal emitters in X-rays and gamma-rays, and supernova remnants (debris from exploding stars) are known to be major production sites of high-energy cosmic rays in our Galaxy. The H.E.S.S. telescopes in Namibia and the FERMI Gamma-ray Space Telescope (see figures) have produced the most detailed maps of the high-energy Universe. Our group is part of the HESS collaboration and we are actively contributing to the analysis of the data on Galactic sources, to better understand the role of massive stars and their winds in particle acceleration. We also study Active Galactic Nuclei across the whole electromagnetic spectrum.
The research group is funded by a Royal Society-Science Foundation Ireland University Research Fellowship, an Irish Research Council Starting Laureate Award, and a DIAS PhD Studentship.
Astronomy and Astrophysics
Our paper on LOFAR Observations of a Jet-driven Piston Shock in the Low Solar Corona is now available on @AAS_Publishing ... doi.org/10.3847/1538-4… Check it out! @IrishResearch @tcddublin @DIASAstronomy @LOFAR Retweeted by DIAS Astronomy & Astrophysics
One year ago today... What a thrill to meet President Higgins and other @scienceirel awardees. Myself and my team have been working hard (from home) for the past year and we look forward to returning to in-person collaboration @DIASAstronomy in the not-too-distant future! twitter.com/PresidentIRL/s… Retweeted by DIAS Astronomy & Astrophysics
Meet the Judges of our "Reach for the Stars" Astrophotography competition! @petertgallagher is Head of @DIASAstronomy & has spent the past two decades studying the Sun its impacts on the Earth. To learn more and submit an entry see dias.ie/reachforthesta… #DIASdiscovers Retweeted by DIAS Astronomy & Astrophysics
For anyone looking for a bit of lockdown reading... Please be our guest 📡🌞 arxiv.org/abs/2102.05552 @IrishResearch @ASTRON_NL @I_LOFAR @DIASAstronomy @DIAS_Dublin @TCD_physics #DIASdiscovers #iamaphysicist #solareclipse Retweeted by DIAS Astronomy & Astrophysics
Today is International Day of Women and Girls in Science, and to celebrate, we’ll be retweeting your selfies all day. So tweet us a picture telling us what you do in physics and share using #IAmAPhysicist. #WomenInScience #WomeninSTEM #WomeninScienceDay #WomeninPhysics Retweeted by DIAS Astronomy & Astrophysics
Today marks the 'International day of Women and Girls in Science'. Below you can meet some DIAS's past and present women leading innovation and empowering women and girls across the world! Our CEO Eucharia Meehan will be chatting with @HeritageHubIRE later today on this topic Retweeted by DIAS Astronomy & Astrophysics
Remembering our last in-person public event, which was one year ago today. A lecture by @hfalcke of @Radboud_Uni who delivered a lecture on the 'The First Image of a Black Hole'. You can watch it back here: youtu.be/mkg_OGjWARI #DIASdiscovers #WatchWednesday Retweeted by DIAS Astronomy & Astrophysics
New co-authored paper out today on @arxiv led by @Brendan_PClarke at @DIASAstronomy identifying signatures of quasi-periodic particle acceleration in a solar flare - from low-frequency radio to hard X-ray arxiv.org/pdf/2102.04267… 🌞 Retweeted by DIAS Astronomy & Astrophysics
“How close are we to finding life beyond the solar system?” rte.ie/brainstorm/201…
This is stunning- @ESASolarOrbiter sends images of Venus, Earth & Mars from the centre of our solar system. Venus is bigger since it’s closer to the sun. Lots more data to come as we explore the sun. And Irish involvement from @enbio_eu @DIASAstronomy & CAPTEC. #spaceinsociety twitter.com/ESASolarOrbite… Retweeted by DIAS Astronomy & Astrophysics
Ready to apply to become a YGT at @ESA? esa.int/About_Us/Caree… Retweeted by DIAS Astronomy & Astrophysics
Reach for the Stars in 2021! We are pleased to announce our astro-photography competition in partnership with @IrishTimes and sponsored by @helloalicepr Learn more: dias.ie/reachforthesta… Retweeted by DIAS Astronomy & Astrophysics
@albertocaniz91, a PhD student of Solar Physics at DIAS and Trinity College Dublin has also been part of the organising committee for our Astrophotography competition. In his free time Alberto is a very passionate photographer... (1/2) Retweeted by DIAS Astronomy & Astrophysics
We're back!!! 🎉🎉🎉 Our first event of 2021 will be hosted online on Monday January 25th at 20:00 CET, streaming live on our YouTube channel! @ciara_a_maguire and @AstroJoeC will tell us all about radio stars! 📡✨ So grab a drink, get comfortable, and join us! Retweeted by DIAS Astronomy & Astrophysics
Delighted to strengthen the (already very strong) links with @DIASAstronomy ! twitter.com/petertgallaghe… Retweeted by DIAS Astronomy & Astrophysics
Meet the Judges of our Astrophotography Competition. First up is @EoinCarley of @DIASAstronomy. Eoin is a Schrödinger Research Fellow, currently working on observation of solar eruptions and flares using the Low Frequency Array (LOFAR). Learn more: dias.ie/2020/12/16/rea… Retweeted by DIAS Astronomy & Astrophysics
Kicking of new links between @DIASAstronomy and @DCUPhysics @DCU_CFAR this morning. We’ll virtually be hosting eight 3rd year Physics & Astronomy students working on @I_LOFAR, SolarMonitor.org and FERMI for the next 3 months. Looking forward to working with new students! Retweeted by DIAS Astronomy & Astrophysics
Please get in touch with me directly if you have any questions about this PhD opportunity! twitter.com/DIASAstronomy/… Retweeted by DIAS Astronomy & Astrophysics
PhD Studentship now available to work with @cm_jackman on planetary magnetospheres! Application deadline 31 January. More information here: dias.ie/phd-planetary-… 🌞🪐
My paper " @LOFAR observations of a jet-driven piston shock in the low solar corona" has been accepted by @AAS_Publishing !! Check it out here arxiv.org/abs/2101.05569 on @arxiv @IrishResearch @tcddublin @DIASAstronomy Retweeted by DIAS Astronomy & Astrophysics