After a one-year delay due to COVID-19 the first radio stations ofthe Radio Neutrino Observatory Greenland (RNO-G) have been deployed in the ice of Greenland near Summit Station.
RNO-G will target neutrinos above 10 PeV, searching for a continuation of the astrophysical neutrino flux as detected by IceCube and potentially discover cosmogenic neutrino at EeV energies.
The deployment team on site in Greenland near Summit Station. Credits: RNO-G
RNO-G builds on long-term experience of radio pathfinders such as RICE, ANITA, ARA and ARIANNA that search for neutrinos in the Antarctic Ice. RNO-G combines the sensitive surface log-periodic dipole antennas as used for ARIANNA, with a combination of deep antennas and a low-noise phased array trigger as featured in ARA. The design of RNO-G also serves as a reference design for the proposed radio neutrino array of IceCube-Gen2.
Prior investigations by collaboration members showed that the ice at Summit Station shows the correct properties for a sensitive radio array. RNO-G is the first ultra-high energy neutrino detector with a view of the Northern sky and the first in Europe. The field will be complementary to any current or future radio detector at South Pole, which is particularly interesting for the potential follow-up of transient sources. Furthermore, the RNO-G field of view coincides with the most sensitive field of view of the optical IceCube detector, enabling the study of Northern sources over an extended range of neutrino energies.
Background shows the novel BigRAID drill, the foreground the setting up of solar panels for the first station. Credit: RNO-G
Also in the view of the global pandemic, the location in Greenland has proven advantageous. While travel and logistics through New Zealand has been limited and heavily restricted, the government of Greenland never completely closed the country for travel during the summer season. Albeit following a strict quarantining policy, a team of in total 14 people (in varying shifts) could travel to Summit this year, Europeans traveling directly to Kangerlussuaq via commercial airlines. The last team members will return home at the end of August.
Drilling hole with a diameter of 28 cm that goes down to 100 meters. Credits: RNO-G
The work during this first deployment season will concentrate on drilling the first holes to 100 meters depth using the novel BigRAID drill as constructed by colleagues from the British Antartic Survey (BAS) specifically for this project. The drill delivers dry holes with a diameter of 28 cm down to 100 meters in less than 2 day shifts, and is relatively lightweight and can easily be operated by two people, with further plans for automation.
Next to the first radio stations, the crew installed server infrastructure and a custom LTE network for data transfer at Summit Station. With a summer population of less than 35 people, the infrastructure at Summit Station is much smaller than what one may extrapolate from the experience at South Pole Station. This constraint requires the radio stations to be fully autonomous, exclusively powered with renewable energies. While in this season only solar panels have been installed, meaning that the radio detector will go dormant during the winter, the collaboration expects to be able to add wind-turbines in one of the following seasons in order to retain full operation all year round.
As deployment is still on-going the final number of stations deployed in this season is still counting up. Two more deployment seasons are planned and ultimately, RNO-G is expected to consist of 35 stations, reaching the highest yearly sensitivity of any neutrino detector at 1 EeV.
More information and a full list of collaborating institutions can be found in the RNO-G design paper (JINST 16 P03025 2021), https://arxiv.org/abs/2010.12279
RNO-G is funded mainly through Belgian (FWO) and German agencies (Helmholtz W2/W3 initiative DFG), and contributions from US partners, including project and logistics support by the National Science Foundation.
Astronet (the consortium of European funding agencies, established for the purpose of providing advice on long-term planning and development of European Astronomy) continues to develop a new Science Vision & Infrastructure Roadmap, in a single document with an outlook for the next 20 years. A delivery date to European funding agencies of mid-2021 is anticipated. Astronet is committed to engaging fully with the wider physics community to ensure a common vision where appropriate and mutually beneficial.
The Science Vision and Infrastructure Roadmap revolves around the research themes listed below:
Origin and evolution of the Universe
Formation and evolution of Galaxies
Formation and evolution of Stars
Formation and evolution of Planetary Systems
Understanding the Solar System and conditions for Life
but will include cross-cutting aspects such as computing and training and sustainability.
After some delays due to the global pandemic, the first drafts of the chapters for the document are now available on the Astronet website (see below) from the Panels asked to draft them, for the community to view and comment on. For the Science Vision & Roadmap to be truly representative it is essential we take account of the views of as much of the European astronomy and space science community as possible – so your input is really valued by the Panels and Astronet.
It is intended that a virtual “town Hall” style event, with the support of the European Astronomical Society will be held in late Spring 2021, where an update on the project and responses to the feedback will be provided. (See update below)
Astronet is a consortium of European funding agencies, established for the purpose of providing advice on long-term planning and development of European Astronomy. Setup in 2005, its members include most of the major European astronomy nations, with associated links to the European Space Agency, the European Southern Observatory, APPEC and the European Astronomical Society, among others. The purpose of the Science Vision and Infrastructure Roadmap is to deliver a coordinated vision covering the entire breadth of astronomical research, from the origin and early development of the Universe to our own Solar System.
The first European Science Vision and Infrastructure Roadmap for Astronomy was created by Astronet, using EU funds, in 2007/08, and updated in 2013/14. Astronet is now producing a single document encompassing both the science vision and infrastructure roadmap with an outlook for the next 20 years.
Update May 2021:
As a next step in developing its science vision, Astronet is holding an open webinar to present current status and seek further advice from the European astronomical community via the European Astronomical Society (EAS). The webinar will include an overview of the process from the chair of the Astronet Board, with presentations from the panels who have been working on draft sections, and plenty of time for questions.
The aim is for further consultation in the next few weeks, followed by production of the report and delivery to the Astronet Board before the end of 2021.
Astronet is a consortium of European research funding bodies and national representatives purposed with developing a new science vision and roadmap, taking forward the pioneering and influential reports last updated around 2015. It includes as associates and observers ESA, ESO and the SKA and has close links to APPEC and the EAS.
The webinar is hosted by the EAS and will take place on 11 June, from 8h00 to 13h30 UTC (ie 9h-14:30h UK, 10h-15h30 CEST).
The JENAS2019 event at Orsay allowed astroparticle, nuclear and particle physics researchers to sniffle into each other’s activities. Being informed by the presentations and discussions and with a view to further explore topical synergies between the disciplines, a call for Expression of Interest (EoIs) was submitted by the then Chairs (Teresa Montaruli, APPEC; Jorgen D’Hondt, ECFA; Marek Lewitowicz, NuPECC) of the three commitees/Consortia, with a request to identify the potential communities across the border of at least 2 of them and elaborate on the synergy topic and possible objectives.
Till now five EoI were received and the current chairs want to inform the community-at-large about these common activities and encourage further engagement and participation.
“Dear Colleagues,
Initiated by the European Committees for Astroparticle (APPEC), Particle (ECFA) and Nuclear Physics (NuPECC), and following a first joint seminar held in Orsay in 2019, Expressions of Interest for common activities have meanwhile been endorsed in the following areas:
Dark Matter (iDMEu)
Machine-learning Optimized Design of Experiments (MODE)
Gravitational Waves for fundamental physics
Nuclear Physics at the LHC
Storage Rings for the Search of Charged-Particle Electric Dipole Moments
All these activities have held their first meetings to present and discuss their Expressions of Interest and to make first steps towards implementation of the common activities in autumn last year (more information is available here).
With this letter we would like to inform the community-at-large about these common activities and encourage further engagement and participation. Interested groups may wish to attend important meetings which are intended to take place during 2021. Below a short summary of the status, planned activities and upcoming workshops is given.
In addition, a new JENAS expression of interest is currently discussed, which would concern the new US-based project, the Electron-Ion Collider. Please, follow the above mentioned webpage of the EoI for news.
Work will be ongoing in all of these activities towards a second Joint ECFA-NuPECC-APPEC Seminar (JENAS) that will be held in Madrid from 3 – 6 May 2022.
With best regards,
Andreas Haungs (APPEC Chair), Karl Jakobs (ECFA Chair), Marek Lewitowicz (NuPECC Chair)”
Initiative for Dark Matter in Europe and beyond (iDMEu) iDMEu is an initiative that aims at building up a “virtual place” where researchers working on Dark Matter from different communities can meet and exchange ideas. Some details can be found here https://indico.cern.ch/event/869195
iDMEu will kick off its activities with a meeting to be held online (via zoom) on 10 – 12 May 2021 between 2 and 6pm European time https://indico.cern.ch/event/1016060/
Machine-learning Optimized Design of Experiments (MODE) MODE targets the use of differentiable programming in design optimization of detectors for particle physics applications, extending from fundamental research at accelerators, in space, and in nuclear physics and neutrino facilities, to industrial applications employing the technology of radiation detection.
Details are available here: https://mode-collaboration.github.io/index.html#home
A first (in-person) workshop on differentiable programming is planned to be held on 6 – 8 Sept. 2021 in Louvain / Belgium https://mode-collaboration.github.io/workshop/index.html
Gravitational Waves for fundamental physics The landmark detection of gravitational waves emitted by black-hole and neutron-star binaries has opened a new era in physics, giving access to hitherto unexplored systems. In parallel to their countless astrophysical applications, these discoveries open new avenues to explore fundamental physics.
More details can be found here: https://agenda.infn.it/event/22947/overview
Further meetings will be announced in due course.
Nuclear Physics at the LHC The main goal of the initiative is to provide a platform to investigate physics of anti-nuclei and hadronic interaction at high energy accelerators and in Space. It aims at facilitating information exchange via common projects and workshops as well as via the availability and maintenance of public analysis and propagation codes.
More details can be found here: https://indico.ph.tum.de/event/4492/
An in-person workshop will be held as soon as the situation with the pandemic allows it and will be announced in due course.
Storage Rings for the Search of Charged-Particle Electric Dipole Moments A three day Heraeus Workshop has taken place end of March to discuss charged particle Electric Dipole Moment measurements. Parallel to ongoing studies at COSY in Juelich/Germany, the next step is to design and build a prototype storage ring, where key concepts can be verified and a first direct proton EDM measurement will be performed. The submission of a Design Study is planned in 2022 in the framework of the “Horizon Europe Work Programme for Research Infrastructures”.
On March 13, 2021, in the middle of the installation campaign (from February 17 till April 4), the Minister of Science and Higher Education of the Russian Federation visited the site of the neutrino telescope to officially launch the detector and to sign the Memorandum of Understanding between the Ministry of Science and Higher Education of the Russian Federation and the Joint Institute for Nuclear Research (JINR) on development of the BAIKAL-GVD Neutrino Telescope. In 2021, BAIKAL-GVD increased its effective volume for showering neutrino interactions up to 0.4 km3.
Winter expedition team with distinguished guests. (Credits: Bair Shaybonov, DLNP)
Nowadays, neutrino telescopes are important instruments of multi-messenger astronomy providing a new powerful method for exploring the Universe. BAIKAL-GVD is one of four such installations in the world. The other three are IceCube at the South Pole, KM3NeT and ANTARES in the Mediterranean Sea. All of them make up the Global Neutrino Network aimed at expertise exchange, cooperative data processing and better general sensitivity due to different locations across the globe.
Neutrino telescopes are intended to investigate the most powerful natural accelerators emitting ultra-high-energy neutrinos, such as Active Galactic Nuclei, promising but not the only candidates. The corresponding research should help to understand the evolution of galaxies, formation of supermassive black holes and mechanisms of particle acceleration.
About cubic-kilometre scale neutrino detectors should be sensitive to tiny neutrino fluxes from the very distant objects. In 2021, BAIKAL-GVD, the largest neutrino telescope in the Northern Hemisphere, is successfully taking data with an effective volume of 0.4 km3. In 2027, BAIKAL-GVD is expected to observe showering neutrino interactions with a volume of one cubic km.
Minister Valery Falkov and JINR director Grigory Trubnikov signing the Memorandum of Understanding between the Ministry and JINR. Leftmost: INR director Maxim Libanov. (Credits: Bair Shaybonov, DLNP)
On March 13, 2021, BAIKAL-GVD was officially inaugurated. Valery Falkov, the Minister of Science and Higher Education of the Russian Federation, and Grigory Trubnikov, the Director of JINR, signed the Memorandum of Understanding between the Ministry of Science and Higher Education of the Russian Federation and JINR.
The ceremony took place on the ice just above the neutrino telescope at the special ice table created by a local Siberian artist. Maxim Libanov, the Director of the Institute for Nuclear Research of the Russian Academy of Sciences (INR, RAS), welcomed distinguished guests and talked about the history, current status and development plans of the Baikal Neutrino Telescope.
The Minister officially launched the detector pressing the start-data-taking button. This event was widely covered by the mass media. The year 2021 was declared in Russia to be the Year of Science and Technology, and the inauguration of BAIKAL-GVD is already regarded as one of its top events.
This year, the International Scientific BAIKAL-GVD Collaboration comprises the Institute for Nuclear Research of the Russian Academy of Sciences (Moscow), the Joint Institute for Nuclear Research (Dubna), Irkutsk State University, Skobeltsyn Institute for Nuclear Physics MSU (Moscow), Nizhny Novgorod State Technical University, St. Petersburg State Marine Technical University, the Institute of Experimental and Applied Physics of Czech Technical University in Prague, the Faculty of Mathematics, Physics and Informatics of the Comenius University in Bratislava (Slovakia), the Institute of Nuclear Physics of the Polish Academy of Sciences (Krakow, Poland) and EvoLogics GmbH (Berlin, Germany).
The 2021 expedition was organized by the Institute for Nuclear Research of the Russian Academy of Sciences (Moscow) and the Joint Institute for Nuclear Research (Dubna).
G.V. Domogatsky (INR, RAS), spokesperson of the BAIKAL-GVD Collaboration
On 1 April the APPEC General Assembly came together online for their first meeting in this year. The new Chair Andreas Haungs announced some changes in personnel at the beginning of the session:
A. Kouchner, new Co-Chair of the APPEC General Assembly.
Antoine Kouchner, director of the APC laboratory, was endorsed as Co-Chair of the General Assembly. He is since many years closely related to APPEC and leads the French functional office of the joint secretary of APPEC. Congratulations to Antoine and we look forward working with him in his new role!
Additionally we welcome our new representatives Nicu Marginean (IFIN) and Alexandra Saftoiu (IFIN) for Romania, Christos Markou (NCSR Demokritos) for Greece and Matthias Marklund (VR) for Sweden.
Last year the Neutrinoless Double Beta Decay APPEC Sub-Committee gave advise on the European (and global) program and as a follow-up action an 0νββ European – North American Summit will be organised from 29 Sep to 1 Oct 2021.
Then Katharina Henjes-Kunst gave an overview about current activities from the General Secretariat including the status of the Town Meeting which will be held 9-10 June 2022 in Berlin and the next APPEC TechForum on Robotics in Harsh Environments, which shall take place in Prague.
The last topic on the agenda was the report from the Direct Detection of Dark Matter Sub-Committee led by Leszek Roskowzki. He gave a summary on the report and then the chair of the Scientific Advisory committee, Sijbrand de Jong, congratulated the members of the DDMD sub-committee for their excellent report and thank them for the hard and thorough work they have put in.
After the report was discussed, the GA endorsed it and it is now published on our website and on arXiv. The follow up actions will be a topic during the next General Assembly meeting in June.
During a week-long sea campaign, 8-14 April 2021, the seafloor infrastructure offshore Sicily has been successfully upgraded. In addition, five new detection units of the kilometre cube neutrino telescope KM3NeT/ARCA have been connected and are operational.
Located in the Mediterranean Sea at a depth of 3500 m, about 80 km offshore Capo Passero, Sicily, the ARCA telescope together with its sister detector ORCA, located offshore Toulon, France will allow scientists to identify the astrophysical sources of high-energy cosmic neutrinos and to study the fundamental properties of the neutrinos, the most elusive and pervasive of the known elementary particles. The two detectors will also provide unprecedented opportunities for Earth and Sea science studies.
Once complete, the KM3NeT/ARCA detector will form an array of more than two hundred detection units. Each of these 700 m tall structures comprises 18 modules equipped with ultra-sensitive light sensors that register the faint flashes of light generated by neutrino interactions in the pitch-black abyss of the Mediterranean Sea.
During the first part of the sea operation, a new junction box, a hub for the power distribution and data transmission of the detection units, was added to the sea floor infrastructure. The junction box is connected via an electro-optical cable to the recently renovated onshore INFN laboratory located in Portopalo di Capo Passero.
In the second part of the operation, five new KM3NeT detection units were deployed, individually connected by a remotely operated submersible to the junction box and unfurled to their final vertical configuration. As a final step, the first detection unit of the apparatus, which had been deployed as early as 2015, was connected to the new junction box.
In total, six detection units are now in operation, representing the initial core of the KM3NeT/ARCA neutrino telescope. With the six ORCA detection units already taking data, the KM3NeT neutrino observatory has now comparable sensitivity to that of its predecessor, the ANTARES neutrino telescope.
KM3NeT is an international collaboration of over 250 scientists from more than fifty scientific institutes around the World. KM3NeT has been included in the list of high priority projects selected by the European Strategy Forum on Research Infrastructures (ESFRI). Paschal Coyle, Spokesperson of the Collaboration emphasises: “The successful deployment and operation of multiple ARCA detection units is another major step forward for the KM3NeT project. Now it’s full steam ahead with the construction of the hundreds of detection units to be deployed at the French and Italian sites.”
The five detection units of KM3NeT onboard the deployment ship. (Credits: KM3NeT)
Deployment of a detection unit of KM3NeT. (Credits: KM3NeT)
ECFA currently organises the development of a Detector R&D roadmap, which is organised in 9 Task Forces, one of them beeing on Training. The ECFA early career researcher panel is currently collecting input from early career researchers on opportunities for training on instruemental related tasks. Also early career researchers from the astroparticle physics community are invited to give feedback:
“The ECFA early career researcher panel has been asked to collect input from early career researchers of all backgrounds, whether you have worked in instrumentation or not, on the opportunities for training that are available for instrumentation-related tasks. In this spirit, we request that all junior researchers (students, post-docs, non-tenured/non-permanent researchers and engineers) take a few minutes of your time to fill out the following survey. Once again, please fill it out even if you have not worked on instrumentation; you will not be asked for as much information in this case, but we still want to hear from you!
Please make sure to fill out the below-linked survey by the deadline of Thursday, April 22! This is important as we will then review your feedback and prepare to present it on behalf of the early career researcher community it at the relevant ECFA working group meeting.
In this survey, you will be asked a series of questions about yourself in order that we can get a high-level overview of who we are representing, followed by a series of questions about the training experiences you may (or may not) have encountered during different stages of your career. In case specific questions are not applicable to your situation, you can choose to not reply to them, as they are not mandatory.
All of the responses are fully anonymous, and results will only ever be shared in aggregate form, thus ensuring your privacy. There are some text boxes, but in such cases we would encourage you to provide answers while keeping the replies anonymous (not mentioning names/etc). If you wish to discuss with us in a non-anonymous way, you are welcome to contact us using the email listed below.
The results of this survey will be shared at the ECFA Detector R&D Roadmap Symposium on April 30th, 2021. You are welcome to participate in that session as well, which can be found at the following link: https://indico.cern.ch/event/1001747/
If you have any questions, or otherwise want to provide non-anonymous feedback, please contact the survey organizers at ecfa-ecr-detector@cern.ch.
Best regards,
The ECFA Early Career Researcher Detector R&D working group”
Interview with Tommaso Dorigo about the MODE collaboration
As reply to the JENAA call for Expression of Interest Tommaso Dorigo and his colleagues proposed a program for Machine-learning Optimized Design of Experiments – MODE. Their main target is the use of differentiable programming in design optimization of detectors for our research field. The first Kick-off Meeting took place last September and they just published a preprint of a short article on their research plan on INSPIRE which will be published by Nuclear Physics News International. In this interview, Tommaso Dorigo will tell us more about MODE and next steps.
Can you explain more about the program and aim of MODE?
For over a century now, physicists have designed instruments to detect elementary particles, and radiation in general, exploiting cutting-edge technologies, and in some cases developing entirely new ones. As the complexity of the apparatuses and of the required tasks grew, so did our inventiveness. This has brought a stream of new developments, which culminated in the past two decades with the construction and operation of giant detectors like ATLAS and CMS, which are mind boggling instruments.
Precisely because of their complexity the design of such apparatuses has followed well-defined paradigms, which have served us well until now, and guided us toward robust design choices and well-established techniques. However, those choices are not – and cannot be – perfectly aligned with our true experimental goals. The reason is that the task of optimizing the design of these apparatuses is absolutely super-human, as it requires the study of configuration spaces of hundreds, if not thousands of dimensions. In fact, a global optimization is usually not even attempted: we use as success-metrics simplified surrogates of our real goals, and this potentially results in huge losses in performance.
A proposed pipeline for the optimization of a muon tomography apparatus (Figure taken from the article on the MODE collaboration published in Nuclear Physics News International, March 2021).
Yet today we can, in principle, rely on artificial intelligence for the exploration of those hugely complex parameter spaces. Differentiable programming techniques allow us to navigate through them, if we provide the right interfaces and construct models of the whole experiment, from the simulation of the events of interest, particle interaction with matter, detector response and reconstruction, and inference extraction. This is very hard, I am not hiding that. But we need to start doing it. MODE has the goal of proving how such a path can be undertaken, to realign our experimental choices with our true goals, and to vastly improve the effectiveness of future detectors.
But MODE is not specifically targeting those giant multipurpose detectors for fundamental physics – quite the contrary, in fact. MODE researchers are starting this ambitious program by working towards smaller-scale practical applications of particle detectors, such as proton therapy or imaging with cosmic muons. In these areas, the detectors are relatively small and their geometry is way less complex than those of particle colliders. Nevertheless, design optimization is far from trivial also in these applications. In fact, the first practical implementation of the MODE program may well be in one of these areas, where the typical timescales from design to operation are relatively short.
At the JENAS 2019 the call for EoI was issued and you came up with the MODE program. Did you and your colleagues already work on this topic before, or did you just start after this event?
I have worked on machine-learning-driven optimization of physics measurements in the past, but my idea of applying the techniques developed in that context to the design of instruments was born while sitting in board meetings of accelerator physics coordination. There, I observed that the design of new detectors for future colliders was being proposed and starting, by the hands of colleagues with decades of experience in instrumentation, without any consideration for the elephant in the room, AI. In 20 years, the extraction of information from detector signals will be entirely automated and in the hands of much more complex and performant algorithms than those in use today. This means that constructing devices with the same paradigms as before is doomed to be enormously suboptimal.
Of course, and fortunately, I am not the only one who realizes this, and in fact efforts in the use of advanced computer science techniques to the optimization of detectors and instruments have started to appear in the past few years. Some of the MODE members are in fact leaders in this area of research, with some important publications already produced. With the help of these colleagues, we thus formed the MODE collaboration, to provide the ground where to build the required interfaces for a more systematic approach to detector design.
To what extent does your collaboration represent the three communities Particle, Astroparticle and Nuclear Physics ?
A view of the CMS experiment at CERN. The complexity of modern particle physics experiments is too high to allow for human-driven optimization. Or, better put, the space of design choices is so vast that the potential for improvement in relevant metrics (discovery potential, data quality) is huge. (Credits:CERN)
Our group for now is small, but highly motivated. I cannot cite everybody here, but MODE includes physicists who are experts in machine learning and already working for calorimetry optimization (Jan Kieseler, at CERN, Fedor Ratnikov, at HSE University and Yandex Data school, and colleagues at National Research University Moscow), track reconstruction (Mia Tosi, at University of Padova), inference extraction (Pietro Vischia, at UCLouvain, and Giles Strong, at INFN-Padova), and muon tomography (Andrea Giammanco, at UCLouvain) – all those tasks are important use cases for MODE, and are not specific of HEP. And we have computer scientists with experience in collaboration with physicists (Atilim Gunes Baydin, at Oxford University, and Gilles Louppe, at Université de Liege); plus Ph.D. students in HEP (Hevjin Yarar and Lukas Layer, at INFN-Padova). But MODE tries to be as inclusive as possible, because of the extremely challenging nature of its research program. We need the interest of everybody who wants to extract information from devices that work by detecting radiation in any form, and therefore it is only natural to look beyond the playground of some of us, which is HEP. Hence we have started to involve colleagues from the astroparticle physics and nuclear physics community, as well as neutrino physics, by inviting them to take part to the advisory committee of a workshop we are organizing, which we hope will be the first of a series, and by asking them to chair sessions there and take part. In conjunction, we are advertising our research plan within those communities, as we believe that our studies will benefit them just as much as HEP.
It is important to realize that particle detectors can be improved quite significantly in their performances by studying even very simple choices, such as moving detection elements around. Last year I did an exercise with a simply designed detector, MUonE, which will be built to reduce a theoretical uncertainty on the g-2 muon anomaly. The experiment aims to measure the differential muon-electron elastic scattering with layers of silicon impinged on by a beam of muons at CERN, and is very simple – so simple that I could study it with a fast simulation and demonstrate that with some optimization a factor of two gain in the relevant metric could be achieved without increase in cost or complexity. A publication ensued, and the collaboration is now using my results for an improved design. But this is just an example.
How can ECFA, NuPECC and in particular APPEC support your activities?
Help in making the MODE research program more visible and known within the communities is certainly important – we have indeed already benefited from the offer of publishing a short manifesto in the Nuclear Physics News International journal. Also, we presently have no explicit funding for MODE, so support for the organization of a yearly workshop will be very welcome.
You plan a MODE Workshop on Differentiable Programming this autumn. What are the aims of the workshop and who should participate?
The workshop aims at making these techniques more widely known, as well as at creating a stable bridge and a communication ground with the computer science community. Anybody who realizes that these tools, which today power artificial intelligent devices all around us, are needed for fundamental physics research in the future should consider coming, listening, or giving a contribution. I mention artificial intelligence in everyday life objects (cellphones, self-driving vehicles, targeted ads, spam filters, etcetera) because these things have changed the paradigms in our society, but this was only possible because it was economically favourable to invest in creating the right interfaces for the problems to be solved. In basic research, we have to create those interfaces ourselves, or we will be stuck to the ice age before we know it.
Are there other events planned or what are the next steps?
Besides the workshop, we are starting to hire – there is a Ph.D. position for a Joint doctorate at the University of Padova and at Université Clermont Auvergne, call open until May 12 at the University of Padova; the student will work on MODE research. We are also starting our activities in two important use cases, the optimization of muon tomography detectors and the study of hybrid calorimeters. We are writing a white paper on the use of differentiable programming for detector design. And we are participating in a proposal to join the ELLIS society within a larger community of HEP and astro-HEP scientists. Finally, we are participating in competitive funding, to provide ourselves with the needed fuel for a long journey.
How can interested scientists join and benefit from MODE?
To join mode you only need to declare your genuine interest in our research plan and to devote a fraction of your research time to some of our activities, or propose others within our interests. We hold online meetings every month or so, and everybody is welcome to attend.
Tommaso Dorigo (Ph.D. 1999) is a particle physicist and machine learning expert who works as a First Researcher for the INFN and teaches Particle Physics and Data Analysis courses at the University of Padova, Italy. He participates to the CMS experiment at the CERN LHC collider, where he is a member of the Statistics Committee, which he chaired in the years of the Higgs boson discovery. In 2020 Dorigo founded and since then coordinates the MODE collaboration. He is an author of over 1600 peer-reviewed scientific publications, and is an editor of the Elsevier “Reviews in Physics” and “Physics Open” journals; since 2006 he has also run a popular blog, visited over 14 million times (http://www.science20.com/quantum_diaries_survivor).
On December 8, 2016, a high-energy particle called an electron antineutrino hurtled to Earth from outer space at close to the speed of light carrying 6.3 petaelectronvolts (PeV) of energy. Deep inside the ice sheet at the South Pole, it smashed into an electron and produced a particle that quickly decayed into a shower of secondary particles. The interaction was captured by a massive telescope buried in the Antarctic glacier, the IceCube Neutrino Observatory.
The electron antineutrino that created the Glashow resonance event traveled quite a distance before reaching IceCube. This graphic shows its journey; the blue dotted line is the antineutrino’s path. (Not to scale.) (Credits: IceCube Collaboration)
IceCube had seen a Glashow resonance event, a phenomenon predicted by Nobel laureate physicist Sheldon Glashow in 1960. With this detection, scientists provided another confirmation of the Standard Model of particle physics. It also further demonstrated the ability of IceCube, which detects nearly massless particles called neutrinos using thousands of sensors embedded in the Antarctic ice, to do fundamental physics. The result was published on March 10 in Nature.
“This result proves the feasibility of neutrino astronomy—and IceCube’s ability to do it—which will play an important role in future multimessenger astroparticle physics,” says Christian Haack, who was a graduate student at RWTH Aachen while working on this analysis. “We now can detect individual neutrino events that are unmistakably of extraterrestrial origin.”
Since IceCube started full operation in May 2011, the observatory has detected hundreds of high-energy astrophysical neutrinos and has produced a number of significant results in particle astrophysics, including the discovery of an astrophysical neutrino flux in 2013 and the first identification of a source of astrophysical neutrinos in 2018. But the Glashow resonance event is especially noteworthy because of its remarkably high energy; it is only the third event detected by IceCube with an energy greater than 5 PeV.
To confirm the detection and make a decisive measurement of the neutrino-to-antineutrino ratio, the IceCube Collaboration wants to see more Glashow resonances. A proposed expansion of the IceCube detector, IceCube-Gen2, would enable the scientists to make such measurements in a statistically significant way. The collaboration recently announced an upgrade of the detector that will be implemented over the next few years, the first step toward IceCube-Gen2.
The IceCube Laboratory at the South Pole. This building holds the computer servers that collect data from IceCube’s sensors under the ice. (Credits: Martin Wolf, IceCube/NSF)
Glashow, now an emeritus professor of physics at Boston University, echoes the need for more detections of Glashow resonance events. “To be absolutely sure, we should see another such event at the very same energy as the one that was seen,” he says. “So far there’s one, and someday there will be more.”
“The detection of this event is another ‘first,’ demonstrating yet again IceCube’s capacity to deliver unique and outstanding results,” says Olga Botner, professor of physics at Uppsala University in Sweden and former spokesperson for the IceCube Collaboration.
Last but not least, the result demonstrates the value of international collaboration. IceCube is operated by over 400 scientists, engineers, and staff from 53 institutions in 12 countries, together known as the IceCube Collaboration. The main analyzers on this paper worked together across Asia, North America, and Europe.
The IceCube Neutrino Observatory is funded primarily by the US National Science Foundation but also with significant European contributions. Research at IceCube, including major contributions to the construction and operation of the detector, is supported in Europe by funding agencies from Belgium, Denmark, Germany, Sweden, Switzerland, and the United Kingdom.
. Pierre Auger Observatory (Credits: Pierre Auger Observatory)
The Pierre Auger Collaboration is releasing 10% of the data recorded using the world’s largest cosmic ray detector. These data are being made available publicly with the expectation that they will be used by a wide and diverse community including professional and citizen-scientists and for educational and outreach initiatives. While the Auger Collaboration has released data in a similar manner for over a decade, the present release is much wider with regard to both the quantity and type of data, making them suitable both for educational purposes and for scientific research. The data can be accessed at www.auger.org/opendata.
Operation of the Pierre Auger Observatory, by a Collaboration of about 400 scientists from over 90 institutions in 18 countries across the world, has enabled the properties of the highest-energy cosmic rays to be determined with unprecedented precision. These cosmic rays are predominantly the nuclei of the common elements and reach the Earth from astrophysical sources. The data from the Observatory have been used to show that the highest-energy particles have an extra-galactic origin. The energy spectrum of cosmic rays has been measured beyond 1020 eV, corresponding to a macroscopic value of about 16 joules in a single particle. It has been demonstrated that there is a sharp fall of the flux at high energy, and emerging evidence of emission from particular near-by sources has been uncovered. Analyses of the data have allowed characterisation of the type of particles that carry these remarkable energies, which include elements ranging from hydrogen to silicon. The data can also be used to test particle physics at energies beyond the reach of the LHC.
At the Pierre Auger Observatory, located in Argentina, cosmic rays are observed indirectly, through extensive air-showers of secondary particles produced by the interaction of the incoming cosmic ray with the atmosphere. The Surface Detector of the Observatory covers 3000 km² and comprises an array of particle detectors separated by 1500 m. The area is overlooked by a set of telescopes that compose the Fluorescence Detector which is sensitive to the auroral-like light emitted as the air-shower develops, while the Surface Detector is sensitive to muons, electrons and photons that reach the ground. The data from the Observatory comprises the raw ones, obtained directly from these and other instruments, through reconstructed data sets generated by detailed analysis, up to those presented in scientific publications. Some of the data are routinely shared with other observatories to allow analyses with fullsky coverage and to facilitate multi-messenger studies.
As pointed out by the spokesperson, Ralph Engel, “the data from the Pierre Auger Observatory, which was founded more than 20 years ago, are the result of a vast and long-term scientific, human, and financial investment by a large international collaboration. They are of outstanding value to the worldwide scientific community.” By releasing data and analysis programs to the public, the Auger Collaboration upholds the principle that open access to the data will, in the long term, allow the maximum realization of their scientific potential.
The Auger Collaboration has adopted a classification of four levels of complexity of their data, following that used in high-energy physics, and adapted it for its open-access policy:
One of the water-Cherenkov detectors (foreground) and a fluorescence-detector station (background). (Credit: Pierre Auger Observatory)
(Level 1) Open-access publication with additional numerical data provided to facilitate re-use;
(Level 2) Regular release of cosmic-ray data in a simplified format, for education and outreach. This began in 2007 when 1% of the data was released and increased to 10% in 2019;
(Level 3) Release of reconstructed cosmic-ray events, example codes, selected with the best available knowledge of the detector performance and conditions at the time of data-taking. Example codes derived from those used by the Collaboration for published analyses are also provided;
The last two levels of information are added in the present release, which includes data from the two major instruments of the Observatory, the 1500 m array of the Surface Detector and the Fluorescence Detector. The dataset consists of 10% of all the events recorded at the Observatory, subjected to the same selection and reconstruction procedures used by the Collaboration in recent publications. The periods of data recording are the same as used for the physics results presented at the International Cosmic Ray Conference held in 2019. The examples of analyses use updated versions of the Auger data sets, which differ slightly from those used for the publications because of subsequent improvements to the reconstruction and calibration. On the other hand, as the fraction of data which is now available is currently 10% of the actual Auger data sample, the statistical significances of measured quantities are reduced with respect to what can be achieved with the full dataset, but the number of events is comparable to what was used in some of the first scientific publications by the Auger Collaboration.
The Pierre Auger Collaboration is committed to its open data policy, in order to increase the diversity of people accessing scientific data and so the common scientific potential for the future.
