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
This work was to help towards the preservation of the Irish Language, to maintain it's continuity with the past, and was to become a resource for teachers to check pronunciation #DIASdiscovers #Irish #Irishlanguage #CelticStudies #Gaelic
The researchers used the International Phonetic Alphabet, slightly modified to represent vowels and consonants of living speech. At that time there were concerns over the deterioration of the Irish language due to the "overpowering influence of English"
Date: 02 June 1943 Paper: The Irish Press Synopsis: In 1943, a phonetic investigation led by Brian Ó Cuív, Risteárd B. Breathnach and Tomás de Bhaldraithe of DIAS would begin the first systematic scientific recording of the varied sounds of modern Gaelic speech.
Happy Birthday! twitter.com/thecelticist/s…
The papers were 1) Affine Field Theory: conservation identitites and relation to Weyl and Eddington 2)The Union of the three fundamental fields (Gravitation, Menson, Electromagnetism) Which went on to secure worldwide acclaim. #DIASdiscovers
Date: 01 December 1943 Paper: The Irish Press Headline: Two Papers by Dr. Schroedinger Synopsis: 1943 was a busy year for Schroedinger. Not only did he deliver the "What is Life?" Lectures in @tcddublin in February in November he delivered two papers in the @RIAdawson (1/2)
Available to buy on the DIAS bookshop: books.dias.ie/index.php?main… (5/5) #DIASdiscovers #celtic #studies #twopatricks
He spoke on "Palladius and Patrick". Palladius was the first bishop of the Christians of Ireland. (2/5)
He was known by his first name Patricius, which in later times would lead to confusion as he was succeeded by another apostle of the same name (Saint Patrick or Patricius in Latin). (3/5)
"In the lives of St. Patrick, the two saints are invariably fused into one", said Prof. O'Rahilly in his lecture. The lecture was a condensation from O’Rahilly’s book “The two Patricks: a lecture on the history of Christianity in fifth-century Ireland”. (4/5)
Date: 21st March 1942 Paper: The Irish Press Headline: Palladius and Patrick | School Of Celtic Studies Lecture Synopsis: The first public lecture under the auspices of the School of Celtic Studies was delivered in Trinity College by Professor T. F. O'Rahilly in 1942. (1/5)
As part of our ongoing participation in the @HistFest we decided to take a look into the Irish Newspaper Archives and see where DIAS made it into print over the last 80 years. There were so many articles, the hardest part was selecting what we would post. We hope you enjoy!
@AReillyFailte @CultureNight @VisitDublin Thanks Antoinette! Glad you enjoyed 😊
Big thank you to @MartinaPQuinn of @helloalicepr for moderating the discussion, and of course to our panel @NeasaMcG @CormacORafferty and @laoneill111
@CormacORafferty "to cut yourself off from fundamental research means you could miss out on some of the biggest ideas"
@laoneill "it's our job as researchers to keep reminding governments how important basic research is" "For Dev basic research being carried out in Ireland was a badge of pride"
@NeasaMcG Schrödinger's work in causality was not well received by the religious authorities at the time At the same time DIAS did have Catholic priests working on research projects in the early days, so there was not the conflict you might think between science and religion