APPEC Updates its Astroparticle Physics Roadmap
7 January 2015
Antonio Masiero
Goals and Challenges for APPEC’s Scientific Advisory Committee
One of the first actions undertaken by the APPEC consortium in 2013 was the appointment of its Scientific Advisory Committee (SAC). The main criterion for SAC membership, as established by the APPEC General Assembly (GA), was the internationally recognised competence of the chosen experts independently from their countries of origin or the institutions/agencies that they represent. Such an independence of the SAC from the particular interests of the agencies or institutions of its members is quite relevant in view of the main scientific advisory task that the SAC is called to. A consequence of the fact that the SAC is not representative of the countries entering APPEC is the presence in the SAC of non-EU members – Francis Halzen and Henry Sobel from US and Yifang Wang from China. Their presence plays a significant role in view of the consideration of European astroparticle physics in a global context that the SAC is called to adopt in its analyses.
The 19 members of the SAC were appointed with the goal of achieving a sound expertise in the areas of interest covered by APPEC: dark matter (Laura Baudis, Jocelyn Monroe), dark energy (Ramon Miquel), neutrino properties (Mauro Mezzetto, Henry Sobel, Yifang Wang, Marco Zito), neutrino mass (Andrea Giuliani), high-energy cosmic rays (Andreas Haungs, Peter Tinyakov), high-energy photons (Felix Aharonian, Michal Ostrowski), high-energy neutrinos (Gisela Anton, Francis Halzen), gravitational waves (Jo van den Brand, Patrick Sutton) and astroparticle theory (Ignatios Antoniadis and Pierre Binetruy – covering in particular the cosmology sector, ie CMB and dark energy-, Antonio Masiero).
Since the beginning of its activities last year, the SAC has started working on the preparation of the scientific input asked by the APPEC GA for its next roadmap on EU astroparticle physics to appear by the end of 2015. The SAC members organized themselves in small working groups operating on various research lines and in strict synergy around two central issues:
- The evolution of the Universe, from the Big Bang or the primordial inflation up to its present structure and its future evolution. This enormous question touches upon many aspects – from theories of inflation to the riddles of dark matter and dark energy, from an understanding of the neutrino sector to a comprehension of the role of fundamental symmetries and the related possible new physical energy scales between the electroweak and inflation scales.
- The evolution – formation and destruction – of cosmic structures. How the particles of the Standard Model and possible new particles not contained therein can influence the genesis, formation and destruction of cosmic structures? This question is related with the multi-messenger studies of high energy photons, neutrinos, high-energy charged particles and gravitational waves.
APPEC Updates its Roadmap
The Roadmap front cover.
This appears to be a very interesting moment for a new European roadmap in astroparticle physics. LHC in its latest run at 8 TeV has made the tremendous achievement of discovering the Higgs particle, hence closing our search for the whole spectrum of particles predicted to exist in the Standard Model (SM); however, no signal of non-SM particles has appeared. Yet, we know that such new physics has to exist: the mass of neutrinos, the existence of dark matter and dark energy, the cosmic asymmetry between matter and antimatter crucial for our existence, all these observational facts are clearly witnessing that the SM physics cannot encompass the whole range of fundamental particles and interactions operating in our Universe.
The absence of new physics signals from direct high-energy searches makes it even more compelling to promote a strong synergy between cosmology, astrophysics and particle physics, hence pushing on what we call astroparticle physics. Here we have witnessed in recent years a growth of what we could define “astronomies of cosmic messengers”, namely cosmic gamma rays, neutrino, antimatter, charged particles, dark matter, gravitational searches; in some of these fields the transition between discovery to actual study (what we can more properly define “astronomy”) has already occurred, in others either we are at the infancy of such a stage (for instance for cosmic neutrinos) or we are still at the previous, discovery level (the case of gravitational waves or dark matter). In preparation for the 2015 APPEC roadmap, the SAC is working on the future “multi-messenger” approach, ie a coordinated and systematically integrated form of cooperation of the various sectors of “cosmic messengers astronomy” that will constitute the main avenue to our particle physics cosmic exploration.
We expect the international astroparticle community, in general, and the EU research agencies, in particular, to be called to take important decisions in 3-4 years from now. Indeed, by ~2018 we’ll have the results of the present generation experiments on dark matter and neutrinoless double beta decay (reaching impressive sensitivities allowing to test important regions of parameter spaces of new physics beyond the SM) together with new results on the searches for gravitational waves, high-energy neutrinos and cosmic rays. At the same time, we’ll have the results of the new LHC run at 14 TeV. Depending on the outcome of all these searches for signals of physics beyond the SM, the SAC is working on scenarios to chart the future discoveries and corresponding theories that will be tested in the next decade or two:
- The consolidation of the recently opened high energy gamma ray astronomy and the opening of the new astronomies: gravitational waves, neutrinos and the high energy cosmic rays
- The understanding of the neutrino sector and its cosmological role
- Large theoretical and experimental progress in the dark matter quest, reaching close to the parameter limits of current theories; the precise study of the parameters of the equation of state of dark energy and, eventually, of those of the inflation potential
European Investment in Astroparticle Physics
The intense work of the SAC, in particular in the last few months, is going to produce a first draft of a “resource-aware” roadmap for the APPEC General Assembly at the APC in Paris on January 9, 2015. Indeed, in addition to scientific considerations, in its report to the APPEC GA the SAC is going to provide the financial implications of its recommendations separated in the periods 2015-2020 and 2021-2025 (obviously including elements of optional funding in case of e.g. detection of gravitational waves, big successes of the neutrino observatories, development of a long-term LBL neutrino program, etc.). The plan is to come up with recommendations for the decade in front of us, which may turn out to be realistic in view of the current spending of research agencies in the astroparticle lines under scrutiny by the General Assembly of APPEC.
From a recent survey that the SAC and APPEC conducted among the funding agencies and the spokespeople of the main EU research infrastructures, it turned out that the European investment in astroparticle physics roughly amounts to 75M euro/year; hence, leaving out of consideration the main variable represented by extra funds coming directly from ministries, regional structural funding, European programmes, etc., the SAC is converging on a 10-year roadmap with the funding from research agencies approximating 700M euro. In such a resource-aware scheme possible scenarios are envisaged, where all the nine astroparticle research lines (gravitational waves, high-energy photons, high-energy neutrinos, high-energy cosmic rays, LBL neutrino physics, double and single beta decay for neutrino masses, dark matter, dark energy and CMB) can receive adequate support to allow for significant breakthroughs in their respective fields of expertise.
After getting the APPEC feedback at the January GA, the SAC will proceed to the final document in May-June 2015 to allow for the APPEC roadmap to see the light by the end of 2015.
Submitted by Antonio Masiero (SAC Chair)
INFN, University of Padua, Italy
Further reading:
2008_ASPERA_roadmap_final
Roadmap update: European Strategy for Astroparticle Physics (2011)