Massive stars produced at the collapse of giant molecular clouds, form compact groups and remain tightly linked during their entire life. Acceleration of particles in these objects can be initiated by interacting winds directly in the vicinity of stars or in the so-called superbubbles driven by stellar winds and SN explosions (see Figure).
The conditions in these objects can be more favorable for particle acceleration to PeV energies than in individual SNRs. This makes the clusters of massive young stars an attractive alternative to SNRs as CR factories contributing to the highest energy CRs around the “knee”.
DIAS researchers have led a team to report on a compelling similarity of the energy and radial distributions of multi-TeV protons extracted from observations of gamma-ray from these extended structures surrounding three young star clusters (for detail see https://www.nature.com/articles/s41550-019-0724-0). The derived 1/r decrement of the CR density with the distance from a star cluster is a distinct signature of continuous, over a few million years, cosmic ray injection into the interstellar medium. The hard (E-2.3 type) energy spectra and the required high acceleration efficiency derived from gamma-ray data, point to clusters of young massive stars as promising candidates for cosmic PeVatrons (accelerators boosting the energy of protons up to energy 1 PeV=1015 eV) and dominant contributors to the flux of highest energy cosmic rays in the Milky Way.
In 2020 we will show how the school carries out advanced research in many areas of the languages, literatures, societies and laws of the Celtic countries, with particular emphasis on Irish.
The School is dedicated to the study of Irish and the other Celtic languages, both written and spoken, throughout their history, as well as related areas of cultural, social and legal history.
The school's theme for DIAS 2020 is
"Exploring Worlds through Words"
As we mark 80 years of discovery, we will be taking a closer look at each of our constituent Schools.
One of the first Schools founded in 1940 was the School of Celtic Studies.
#DIASdiscovers#DIAS2020#celticstudies
Today we launched DIAS 2020: marking 80 year of discovery with a number of themed events based on our primary disciplines.
The programme to date is available on our events page and will be updated as the year goes on!
More: dias.ie/dias2020/#DIASdiscovers#DIAS2020
#OTD in 2019 @mitchelloconnor unveiled a portrait of Dr Sheila Tinney here at DIAS. Dr Tinney was appointed the first ever female fellow at DIAS and later became a Research Associate at the Institute’s School of Theoretical Physics.
Today also marks her birthday 🎂
#DIASdiscovers
Busy start to the week: An international team led by scientists from DIAS has discovered that large portions of the tectonic plate, or lithosphere, beneath Africa have disappeared over the past 200 million years
More ➡️ dias.ie/2020/01/13/dia…@dias_geophysics#DIASdiscovers
DIAS-led team finds evidence that Young Star Clusters make Cosmic Rays
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Last Updated: 21st January 2020 by Niamh Breathnach
Massive stars produced at the collapse of giant molecular clouds, form compact groups and remain tightly linked during their entire life. Acceleration of particles in these objects can be initiated by interacting winds directly in the vicinity of stars or in the so-called superbubbles driven by stellar winds and SN explosions (see Figure).
The conditions in these objects can be more favorable for particle acceleration to PeV energies than in individual SNRs. This makes the clusters of massive young stars an attractive alternative to SNRs as CR factories contributing to the highest energy CRs around the “knee”.
DIAS researchers have led a team to report on a compelling similarity of the energy and radial distributions of multi-TeV protons extracted from observations of gamma-ray from these extended structures surrounding three young star clusters (for detail see https://www.nature.com/articles/s41550-019-0724-0). The derived 1/r decrement of the CR density with the distance from a star cluster is a distinct signature of continuous, over a few million years, cosmic ray injection into the interstellar medium. The hard (E-2.3 type) energy spectra and the required high acceleration efficiency derived from gamma-ray data, point to clusters of young massive stars as promising candidates for cosmic PeVatrons (accelerators boosting the energy of protons up to energy 1 PeV=1015 eV) and dominant contributors to the flux of highest energy cosmic rays in the Milky Way.
Category: Astronomy and Astrophysics Section News & Events, News
In 2020 we will show how the school carries out advanced research in many areas of the languages, literatures, societies and laws of the Celtic countries, with particular emphasis on Irish.
The School is dedicated to the study of Irish and the other Celtic languages, both written and spoken, throughout their history, as well as related areas of cultural, social and legal history. The school's theme for DIAS 2020 is "Exploring Worlds through Words"
As we mark 80 years of discovery, we will be taking a closer look at each of our constituent Schools. One of the first Schools founded in 1940 was the School of Celtic Studies. #DIASdiscovers #DIAS2020 #celticstudies
Today we launched DIAS 2020: marking 80 year of discovery with a number of themed events based on our primary disciplines. The programme to date is available on our events page and will be updated as the year goes on! More: dias.ie/dias2020/ #DIASdiscovers #DIAS2020
The DIAS School of Cosmic Physics is delighted to announce that Dr Duygu Kiyan has been appointed a Schrödinger Fellow in Geophysics. ➡️dias.ie/2020/01/21/dr-… @dias_geophysics #DIASdiscovers
DYK: @dias_geophysics was at @BTYSTE in the @TheRDS in early Jan twitter.com/dias_geophysic…
#OTD in 2019 @mitchelloconnor unveiled a portrait of Dr Sheila Tinney here at DIAS. Dr Tinney was appointed the first ever female fellow at DIAS and later became a Research Associate at the Institute’s School of Theoretical Physics. Today also marks her birthday 🎂 #DIASdiscovers
Busy start to the week: An international team led by scientists from DIAS has discovered that large portions of the tectonic plate, or lithosphere, beneath Africa have disappeared over the past 200 million years More ➡️ dias.ie/2020/01/13/dia… @dias_geophysics #DIASdiscovers