In very many astronomical systems, ranging in scale from planetary magnetospheres to clusters of galaxies, we see evidence of charged particles with energies very much higher than those of the bulk thermal distributions in these systems. This evidence takes the form both of direct observations (cosmic rays), observations of secondary non-thermal electromagnetic radiation (synchrotron, inverse Compton, Bremstrahlung, neutral pion decay etc) and potentially in the near future observation of high-energy secondary neutrinos produced by these particles. Understanding the mechanisms that accelerate these particles, and the processes by which they generate the observed secondary signals, is the aim of theoretical high-energy non-thermal astrophysics. A primary mechanism is though to be a variant of Fermi acceleration associated with strong collisionless shock waves and indeed at the phenomenological level there is a clear association between shock waves and non-thermal signatures in systems as diverse as the solar wind, supernova remnants, jets from active galactic nuclei and intracluster shocks in the intergalactic medium.
This work relies heavily on a combination of theoretical models and numerical simulations. It sits at the intersection of plasma physics with cosmic ray studies and high-energy astrophysics.
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Last Updated: 22nd March 2016 by Anne Grace
Particle Acceleration Theory, Interstellar Gas Dynamics and Plasma Astrophysics
In very many astronomical systems, ranging in scale from planetary magnetospheres to clusters of galaxies, we see evidence of charged particles with energies very much higher than those of the bulk thermal distributions in these systems. This evidence takes the form both of direct observations (cosmic rays), observations of secondary non-thermal electromagnetic radiation (synchrotron, inverse Compton, Bremstrahlung, neutral pion decay etc) and potentially in the near future observation of high-energy secondary neutrinos produced by these particles. Understanding the mechanisms that accelerate these particles, and the processes by which they generate the observed secondary signals, is the aim of theoretical high-energy non-thermal astrophysics. A primary mechanism is though to be a variant of Fermi acceleration associated with strong collisionless shock waves and indeed at the phenomenological level there is a clear association between shock waves and non-thermal signatures in systems as diverse as the solar wind, supernova remnants, jets from active galactic nuclei and intracluster shocks in the intergalactic medium.
This work relies heavily on a combination of theoretical models and numerical simulations. It sits at the intersection of plasma physics with cosmic ray studies and high-energy astrophysics.
Category: Research
Have you registered for our commemorative 'What is Life?' public lecture series? Part 1 taking place on Thursday with @petertgallagher. More info here: bit.ly/2FbUl5J
Trína tograí ceannródaíocha sna daonnachtaí digiteacha, anois tá saothar @SCSLibrary ar fáil ar fud an domhain ar an idirlíon. Sampla is ea an togra Ogham in 3D de thogra a chuidíonn go mór le caomhnú ár gcultúir #DIASdiscovers #SnaG19
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Sa leabharlann ag @SCSLibrary tá an bailiúchán is cuimsithí agus is inrochtana de leabhair agus irisí faoin Léann Ceilteach ar oileán na hÉireann. #SnaG19 #DIASdiscovers
✨ Ag siúl siar le haghaidh #SnaG19 ✨ I DIAS sa bhlian 1978 foilsiú Corpus Iuris Hibernici, le Binchy - an phríomh obair ar dhlíthe Brehon go dtí an lá atá inniu ann. #DIASdiscovers
Ag siúl siar le haghaidh #SnaG19! I 1972 bhí DIAS freagrach as an gcéad turgnamh Éireannach riamh sa spás agus ar dhromchla na gealaí (misean NASA, Apollo 16) #DIASdiscovers
I 1943, thug Schrodinger (an chéad Stiúrthóir ar Scoil na Fisice Teoiriciúla in DIAS & buaiteoir na duaise Nobel) a shraith léachtanna cáiliúla "What is life?" i @tcddublin Aitheantas tugtha ag Crick &Watson gur spreag na léachtaí seo a bhfionnachtain DNA #SnaG19 #DIASdiscovers
Ag siúl siar le haghaidh #SnaG19! I 1959 foilsiú Imleabhar 1 de ‘Linguistic Atlas and Survey of Irish Dialects’ (1959-1969), le H. Wagner, príomh-dhoiciméad tagartha go dtí an lá atá inniu ann. #DIASdiscovers @SCSLibrary
Fantastic to see @MurphyEoghan visiting @ESO HQ in Santiago as part of the #StPatricksDay2019 programme. Professor Tom Ray of DIAS was appointed by the Government in 2018 as the astronomer representing Ireland on the ESO Council. #DIASdiscovers twitter.com/IrlEmbChile/st…
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Register now for our 'What is Life?' lunchtime lecture series. Part 1 on March 21st will feature @petertgallagher exploring: ‘What is Extra-terrestrial Life?’ For more info & registration: bit.ly/2FbUl5J
Over the past few days we've been hosting the 3D Earth Science Meeting at Burlington Rd. We've heard some v interesting talks on different aspects of the Earth's structure & dynamics from international experts including from @ESA_EO ,@kieluni, @Macquarie_Uni, @GFZ_Potsdam & more!
'What is Life?' lecture series returns to Dublin after 75 years via @Irish_TechNews irishtechnews.ie/what-is-life-l…
Delighted to see one of the images from the launch of our ‘What is Life?’ lecture series featured as one of the @IrishTimes Images of the Day ✨#DIASdiscovers @petertgallagher irishtimes.com/news/ireland/i…
@radastrat Fáilte romhat, Anna. Our pleasure to have featured you!
To mark #IWD2019 we're profiling some of the fantastic women that have passed through the doors of DIAS- one from each of our 4 schools. Read more about the great: Máire Herbert,Anna Scaife,Carmel Lowe & the late Cecile DeWitte-Morette here. #DIASdiscovers bit.ly/2TCYTu3