Workshop to discuss participation in the Cherenkov Telescope Array project in Ireland.

Funded by the Irish Research Council New Foundations scheme

Venue: DIAS, 10 Burlington Road, Dublin 4

Date: Monday August 28, 2017, 10am – 5pm (approx.)

The Cherenkov Telescope Array (CTA) (https://www.cta-observatory.org) is a multinational, worldwide project to build a new generation ground-based gamma-ray instrument with an order of magnitude improvement in the sensitivity compared to the current instruments and extension of the accessible energy range to above 100 TeV. There are two sites for CTA, one on La Palma in the Canary Islands, the other in Chile close to the ESO VLT and ELT telescopes.

This workshop will continue the discussion started during the January meeting in Armagh which  focussed on opportunities for scientists across the island of Ireland to engage in the CTA. During that meeting it was decided to establish a CTA-Ireland association. The objectives of this association are to promote participation by Ireland in the CTA Consortium at all levels, scientific, industrial and political, and to engage in public outreach activities in support of CTA. Irish scientists from 6 institutes have already signed an agreement to become members of the CTA-Ireland association.

Currently scientists from Dublin are involved into the scientific simulations needed to define best observational strategy. Scientists from Armagh are working on the provision of the maps of the distribution of molecular clouds for the CTA observatory, needed to interpret the data produced primarily by these telescopes. These efforts could be joined and expanded for full involvement in the CTA project. In particular, the expertise of Irish scientists could be important to address one of the main challenges with CTA – the acquisition and processing of the enormous volumes of data it will produce. CTA will handle up to one hundred telescopes, each producing data in parallel at rates ranging from a few megabytes to several gigabytes per second. Besides the raw data streams, the telescopes will also produce high volume control and engineering data streams. This requires the development of new data management techniques. Our joint efforts could contribute to several key packages to aid the CTA data effort.

Undoubtedly there are other opportunities. For instance, in the exploration of the time domain for high-energy astrophysics and the need for complementary observations at other wavelengths to detect and interpret sources.

The CTA will explore our Universe in depth at very high energies and investigate cosmic nonthermal processes. CTA will serve as an open observatory for a wide astrophysical community, and will be the principal instrument that will provide deep insight into the generation of the most energetic particles in nature.

The CTA Consortium consists of over 1200 members working in 200 institutes from 32 countries. CTA is included in the 2008 roadmap of the European Strategy Forum on Research Infrastructures (ESFRI). It is one of the “Magnificent Seven” of the European strategy for astroparticle physics published by ASPERA, and highly ranked in the “strategic plan for European astronomy” of ASTRONET.

The aim of this workshop is to bring interested scientists together from across Ireland to discuss these opportunities and explore routes for collaboration and further engagement in the CTA. We will have representatives from CTA as well as the CTA-UK consortium present in the meeting to provide a broad perspective on the CTA project and its needs and challenges.

Registration

If interested in attending please email Masha Chernyakova (masha.chernyakova@dcu.ie) at DCU. If interested in giving a presentation, for instance related to possible opportunities or relevant expertise that you might be able to contribute to CTA, please let her know.

L-r: Prof. Luke Drury (DIAS), Prof. Christian Spiering (DESY-Zeuthen)

Professor Christian Spiering was awarded the 2017 O’Ceallaigh medal at the opening of the 35th International Cosmic Ray Conference in Busan, Korea, on Thursday 13th July.  The medal was  presented by Professor Luke Drury, Director of the School of Cosmic Physics at DIAS.

The O’Ceallaigh medal was established by DIAS and the estate of Cormac O’Ceallaigh to honour individuals who have made major contributions to what is now called Astroparticle physics.  The medalist is selected by the Astroparticle physics commission of the International Union of Pure and Applied Physics, and the O’Ceallaigh medal is regarded as the premier award in the field.

Cormac O’Ceallaigh was a distinguished Irish physicist who worked in the DIAS School of Cosmic Physics from 1953 to 1984. He did important early work on meson physics including their neutrino decay modes before turning in later life to questions of the composition of cosmic rays.

Professor Spiering, who was born in what was then East Germany, now works in DESY-Zeuthen near Berlin. Professor  Karl-Heinz Kampert, chair of the commission on Astroparticle Physics, noted that Professor Spiering had been selected “for his outstanding contributions to cosmic ray physics and to the newly emerging field of neutrino astronomy in particular”.  Presenting the medal Professor Drury remarked “It is particularly appropriate that we honour Christian Spiering today because some of O’Ceallaigh’s  early work was on neutrino physics”.

The Commission on Astroparticle Physics (C4), previously known as the Commission on Cosmic Rays, was established by the International Union of Pure and Applied Physics in 1947 to promote the exchange of information and views among the members of the international scientific community in the general field of Astroparticle Physics.

The Dublin Institute for Advanced Studies (DIAS) is a statutory corporation established in 1940 under the Institute for Advanced Studies Act of that year. It is a publicly-funded independent centre for research in basic disciplines. DIAS has three constituent schools: The School of Celtic Studies, The School of Theoretical Physics, The School of Cosmic Physics.

Further information about DIAS is available at www.dias.ie.

For more information on the medal see https://www.dias.ie/2013/07/05/astro-aboutus-oceallaigh/

For more information on Christian Spiering see https://www-zeuthen.desy.de/~csspier/

An international team of astronomers have used ALMA (Atacama Large Millimeter/submillimeter Array), the world’s largest radio telescope, to make the most detailed image of the surface of a star (other than our Sun) that has ever been created at radio wavelengths. The image was taken of Betelgeuse, the famous Red Supergiant located in the constellation Orion, and remarkably reveals that the temperature in its inner atmosphere is far from uniform. The discovery could help explain how the atmospheres of these stars are heated and how material from these stars is transported to the interstellar medium.

“ALMA now provides us with the capabilities to image surface features on nearby stars while also directly measuring the temperature of these features” explains Dr. Eamon O’Gorman, an Irish Research Council Fellow and Astronomer at the Dublin Institute for Advanced Studies, who led the team. “We have known for decades that the visible surface of Betelgeuse is not uniform, but ALMA has now shown in beautiful detail that the temperature in its inner atmosphere is also not uniform. It looks like these temperature fluctuations could be caused by magnetic fields, similar to what we see on the Sun, our nearest star.” The team’s results have recently been published in the journal ‘Astronomy & Astrophysics’.

In terms of size, Betelgeuse is enormous, being about 1400 times larger than our Sun, and more than one billion times larger in terms of volume. As stars like Betelgeuse evolve, they expel an enormous amount of themselves back into the interstellar medium via stellar winds.  These winds contain crucial heavy elements that the stars have manufactured and are vital ingredients for the next generation of stars and planets.

“Located about 650 light years away, Betelgeuse is certainly not the closest star to our solar system, but its sheer size makes it an ideal target to image directly with ALMA”, says Dr. Pierre Kervella, astronomer at the Paris Observatory and member of the team, he continued, “When we look at the night sky with our naked eyes, we see bright stars everywhere, but because they are so small, even the most powerful telescopes in the world struggle to image their surfaces. Our results show ALMA has the capability to image the surfaces of the largest stars in detail.”

Consisting of 66 gigantic 12-metre and 7-metre antennas, ALMA is the most powerful radio telescope in the word. The telescopes can separate over distances of 16 kilometres, giving ALMA an extraordinarily powerful “zoom”. ALMA is an international astronomy facility located at 5000 metres altitude at Chajnantor in northern Chile, at one of the driest sites in the world. ALMA is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile and is the world’s largest astronomy project.

Image 1:

The new ALMA image of Betelgeuse. The overplotted circles allow the size of Betelgeuse to be compared to the size of the orbits of the planets in our solar system.

(Credit: ESO/ALMA/P. Kervella)

Image 2:

ALMA on the Chajnantor Plateau, located at an altitude of 5000 meters in the Chilean Andes. ALMA consists of 66 individual antennas  which combine their signals together and can be separated by distances of up 16 kilometres.

Credit: Clem & Adri Bacri-Normier (wingsforscience.com)/ESO