One century after Einstein’s prediction, half a century of constant cutting edge technological innovations and the tenacity of a world-wide community hunting for gravitational -waves have paid off: the first gravitational wave passing through Earth was detected on September 14, 2015 at 09:50:45 UTC! The announcement was made by the LIGO Scientific Collaboration and the Virgo Collaboration using data from the two LIGO detectors. The results have been accepted for publication in the journal Physical Review Letters.
APPEC Chair Frank Linde said: “It is with tremendous pleasure that I congratulate the LIGO-Virgo Collaboration on this monumental achievement. For sure this will prove to be a turning point in astronomy and cosmology as well as in fundamental studies of the poorest known fundamental force in Nature: Gravity. Collectively we just acquired a new tool: gravitational waves – the power of which we are all very eager to explore.
“Personally, I can hardly believe the extraordinary beauty and the wealth of information hidden in the 0.2 second long ‘ripples’ recorded by the two laser interferometers located in Hanford (WA) and Livingston (LA). Each one alone recorded the tell-tale signal of the coalescence of two massive objects (most likely black holes) as well as the subsequent ring-down signature of the merged black hole. Corrected for propagation delay (few milliseconds) and relative detector orientation, the two signals are perfectly consistent and a huge treasure trove for our scientists as already witnessed by the released publications and, I am sure, by the flood of publications to appear in the coming months.
“Regarding APPEC, Astroparticle Physics European Consortium, this first detection of a gravitational wave could not come at a better time since we have just scheduled a Town Meeting in the Grand Amphithéatre de Sorbonne in Paris on 6-7 April 2016 to discuss our new European Roadmap of Astroparticle Physics This discovery puts discussions on next generation gravitational-wave detectors like the Einstein Telescope centre stage! But today is for the LIGO-Virgo teams to enjoy, and we look forward to seeing how the world responds to their wonderful news.”
Scientists from the KM3NeT Collaboration have publicly announced KM3NeT 2.0, their ambition for the immediate future to further exploit the clear waters of the deep Mediterranean Sea for the detection of cosmic and atmospheric neutrinos. The published Letter of Intent details the science performance as well as the technical design of the KM3NeT 2.0 infrastructure.
The two major scientific goals of KM3NeT 2.0 are the discovery of astrophysical sources of neutrinos in the Universe with the KM3NeT/ARCA detector and the measurement of the neutrino mass hierarchy using atmospheric neutrinos with the KM3NeT/ORCA detector.
The KM3NeT scientists estimate that with the ARCA detector installed at the KM3NeT-It site south of Sicily, Italy, the observation of the cosmic neutrino flux reported by the IceCube Collaboration will be possible within one year of operation. With the ORCA detector installed at the KM3NeT-Fr site south of Toulon, France, they expect to determine neutrino mass hierarchy with at least 3-sigma significance after three years of operation.
The Astroparticle Physics European Consortium invites you to a town meeting at the Grand Amphithéatre de Sorbonne in Paris on the 6 and 7 April 2016 to discuss an update of the 2011 APPEC Astroparticle Physics roadmap, to be published in September 2016.
In 2014, APPEC decided to launch an update of the 2011 Roadmap, transforming it to a “resource aware” roadmap. The intention was to gauge the financial impact of the beginnings of operation of the large global scale observatories put forward in the previous roadmap and to examine the possibilities of international coordination of future global initiatives. The APPEC Scientific Advisory Committee examined the field and prepared a set of recommendations. Based on these recommendations, the APPEC General Assembly drafted a set of “considerations” to be published by end of February 2016 and be debated in an open dialogue with the community, through the web page but primarily at the town meeting of 6-7 April. Based on this debate the final recommendations of APPEC will appear by September 2016.
During the 6-7 April meeting, there will be presentations and discussions around the nine subdomains of astroparticle physics separated in four larger topics (Early Universe, Dark Universe, Neutrinos and High Energy Universe). At the end of the first day, Nobel laureate 2015 T. Kajita will give a general public talk on neutrino physics. The town meeting will close with a round table discussion, including presentations comments and discussions with non-European international agencies.
On the morning of 3 December, the installation of KM3NeT began, as the first vertical neutrino detection string was put in place in the depths of the Mediterranean Sea south of Sicily, and began delivering data. Hundreds of detection strings will be used to build the next generation neutrino telescope, each one carrying 18 light sensor modules to register the faint flashes of Cherenkov light that signal the interaction of neutrinos with the seawater surrounding the telescope.
Marco Circella, the technical coordinator of KM3NeT explained “The large depth of sea water shields the telescope from particles created by cosmic rays in the atmosphere above the telescope. Constructing such a large infrastructure at these depths is a tremendous technical challenge. Making the underwater connections requires custom-designed electrical and fibre optic connectors. The crew of the Ambrosius Tide are experts in performing such delicate submarine operations.”
The string was successfully powered on from the shore, and data started to arrive. Rosanna Cocimano, who coordinates the power systems for KM3NeT outlined the process: “An electro-optical network of cables distributes the high-voltage power from the shore station to the sensor modules in the deep sea. The measured light signals are digitised by the sensor modules and the resulting data returned to the shore station via optical fibres.”
Maarten de Jong, director of KM3NeT said: “This important step in the verification of the design and the technology will allow the KM3NeT Collaboration to proceed with confidence toward the mass production of detection strings and their installation at the sites in the Mediterranean Sea off-shore from Italy and France. A new era in neutrino astronomy has begun.”
LISA Pathfinder is designed to demonstrate that free particles follow geodesics in space-time. It will do this by tracking two test masses in free fall using very precise laser interferometry. The spacecraft faced the challenge of keeping the test masses safe during the launch, whilst then being able to keep them in space with no external forces acting on them.
The distance between the test masses on board the spacecraft is too small to detect gravitational waves, but it is designed to show the technologies needed for a future mission that would be large enough to make the effects of a low-frequency gravitational wave measurable.
The mission carries the LISA Technology Package including inertial sensors, interferometric readout, payload computer and diagnostic system – provided by European companies, research institutes, and the European Space Agency; and the Disturbance Reduction System which is testing technology for NASA and consists of a processor running drag-free control software, and micro-Newton colloidal thrusters.
LISA Pathfinder ready for launch
The spacecraft was launched aboard a Vega rocket to a parking orbit around Earth. It will use its own propulsion module to travel on to the first Sun-Earth Lagrange point, L1. The journey and calibration phases will take a total of about three months. The European Space Agency intends to fly a large mission dedicated to the gravitational Universe as the third large mission of the current Cosmic Vision programme. The expected launch is in 2034.
The GCT prototype is first CTA telescope prototype equipped with an operational camera. It uses high-speed digitisation and triggering technology capable of recording images at a rate of one billion frames per second and sensitive enough to resolve single photons. To detect the short flashes of light produced by gamma rays as they hit the Earth’s atmosphere, the telescope’s camera has to be about a million times faster than a DSLR camera.
The telescope uses the Schwarzschild-Couder dual-mirror optical design, giving it good image quality over a large field of view and making it lighter than a single-mirror system.
The GCT is one of CTA’s small size telescopes (SSTs) and will cover the high end of the CTA energy range, between about 5 and 300 TeV (tera-electronvolts). Around 70 SSTs are needed to make sure the array is sufficiently sensitive at these enormous energies. Other small size telescopes are being prototyped and tested in Italy and Poland.
The AugerPrime symposium held on 15-16 November 2015 saw the signing of a new international agreement for the operation of the Pierre Auger Observatory for the exploration of cosmic rays until 2025. Collaborators and science funding agency representatives gathered in Argentina to sign the agreement, which will allow for new scintillation detectors to be added to the 1660 existing detectors, as well as faster and more powerful electronics.
Astrid Chantelauze, science outreach manager of the Helmholtz Alliance for Astroparticle Physics and Marie-Noëlle Rolland, freelance graphic designer, created a blog for their attendance at AugerPrime.
There is five times more dark matter in the Universe than “normal” matter, the atoms and molecules that make up all we know. Yet, it is still unknown what this dominant dark component actually is. Today, an international collaboration of scientists inaugurated the new XENON1T instrument designed to search for dark matter with unprecedented sensitivity, at the Gran Sasso Underground Laboratory of INFN in Italy.
Dark matter is one of the basic ingredients of the Universe, and efforts to detect it with laboratory-based experiments have been ongoing for decades. However, until today dark matter has been observed only indirectly via its gravitational interactions – the interactions that govern the dynamics of the Cosmos at all length-scales. It is expected that dark matter is made of a new, stable elementary particle which has so far escaped detection. About 100,000 dark matter particles are expected to pass through an area of 1 cm² per second. The fact that these particles have not yet been directly detected puts stringent constraints on their tiny interaction probability with the atoms of ordinary matter. It also implies that more sensitive instruments are required to find the rare signature of the dark matter particle. The international XENON Collaboration, consisting of 21 research groups from the United States, Germany, Italy, Switzerland, Portugal, France, the Netherlands, Israel, Sweden and United Arab Emirates, celebrated the inauguration of their new XENON1T instrument today, which will search for dark matter with unprecedented sensitivity.
The event took place at the Gran Sasso National Laboratory of the Italian National Institute for Nuclear Physics (INFN-LNGS), the largest underground laboratory in the world for astroparticle physics. The inauguration was attended by the XENON scientists along with guests from funding agencies as well as journalists and colleagues. About 80 visitors were able to join the ceremony directly at the experimental site in the 100m long, 20m wide and 18m high hall B of LNGS, which is itself below 1400m of rock. Here, the new XENON1T instrument is installed inside a 10m-diameter water tank to shield it from radiation which originates from the environment. Even more guests followed the introductory presentations in the LNGS auditorium, where Elena Aprile, Professor at Columbia University (New York) and founder of the XENON project, illustrated the evolution of the XENON program from the early beginnings with a 3kg detector 15 years ago to the present-day instrument XENON1T with a total mass of 3500kg.
Fighting against radioactivity
XENON1T employs the noble gas xenon as the dark matter detection material, which must be made ultra-pure and cooled down to –95°C to make it liquid. The large-mass instrument features an extremely low radioactive background in order to be able to identify the rare events from dark matter interactions. For this reason, the XENON scientists have carefully selected all materials used in the construction of the detector, ensuring that their intrinsic contamination with radioactive isotopes meets the experiment’s low-background strict requirements.
The XENON1T detector measures the tiny flashes of light and charge which are generated when a particle interacts with the xenon. The scientists use this information to reconstruct the position of the particle interaction within the detector, as well as the deposited energy and whether the interaction may have been induced by dark matter. The light is observed by 248 sensitive photosensors, which are each capable of detecting even single photons. A vacuum-insulated double-wall cryostat, essentially a gigantic version of a thermos flask, contains the cryogenic xenon and the dark matter detector. The xenon gas is cooled down and purified in the three-story tall XENON building, a fancy installation with a transparent glass facade right next to the water tank, allowing visitors to actually see what the scientists are doing inside. A gigantic stainless-steel sphere equipped with pipes and valves is installed on the ground floor. It can accommodate 7.6 tons of xenon in liquid and gaseous form, more than two times the capacity needed for XENON1T. This will allow the collaboration to swiftly increase the sensitivity of the experiment by using a larger mass detector in the near future.
Aiming for a dark matter detection
Once fully operational, XENON1T will be the most sensitive dark matter experiment in the world. The detector installation has been completed just a few days ago and the first tests of its performance have already been started. The first science results are expected early 2016, as only one week of good data is sufficient to yet again take the lead in the field. The design goal of the experiment will be reached after two years of data taking, as the collaboration explains in a detailed sensitivity study published at the same time as the inauguration. The ultimate goal is the detection of the dark matter particle. Still, even if there are only some hints found after two years of operation, the XENON collaboration will be in an excellent position to move forward, as the next phase of the project, XENONnT, is already being prepared. It will largely use already existing infrastructure, and will increase the sensitivity to dark matter by another order of magnitude.
The International Cosmic Day enables students to get in contact with astroparticle physicists to get a first insight into their research, experimental methods and everyday work. Some basic questions which will be adressed are:
What are cosmic particles?
Where do they come from?
How can they be measured?
The 4th International Cosmic Day on November 5, 2015 is organized by DESY, together with Netzwerk Teilchenwelt, IPPOG, QuarkNet and Fermilab and will enable students in many different countries around the world to get to do their own experiments at nearby universities, research institutions or even in their classrooms. We invite students to:
Perform their own cosmic particle experiment
Analyze and present their data on a common website
Compare their own results with the results of others
Work like in an international research collaboration
Get in contact with scientists and physics
In September 2015 the Horizon 2020 work programs for the period 2017-2018 will be released by the European Commission. APPEC invites all interested astroparticle physicists, colleagues from neighboring scientific fields and companies interested in F&E cooperations to a community workshop.
After the APPEC Horizon 2020 workshops in November 2013 (Zeuthen) and February 2014 (Paris) with this third workshop APPEC wants to achieve the following:
1. Analyse and discuss the experience of the first two years of Horizon 2020 and give advice on how to prepare successful proposals in future calls.
2. Inform about the upcoming funding opportunities and support the community in preparing their proposals for the calls.
3. Prepare with the community astroparticle infrastructure related activities and collaborative actions to be discussed with the European Commission as topics of future work programs (2019 and beyond).
The program of the workshop will be composed by experts’ presentations on the various funding instruments – including individual grants – and open discussions. Furthermore, astroparticle groups can ask for dedicated sessions to setup and plan their strategy for collaborative projects.
Special emphasis shall be put on proposals for calls in the Future Emerging Technology (FET) and the Leadership in Enabling and Industrial Technologies programs of Horizon 2020; representatives of companies interested in common R&D projects are welcome to participate in the workshop. The Spreading Excellence and Widening Participation program (“Teaming and Twinning”) as well as the Research Infrastructures program with focus on e-infrastructures and big data shall be covered.
