EPJ Plus Focus Point Issue: Advances in cryogenic detectors for dark matter, neutrino physics and astrophysics
- Published on 24 June 2022
Guest Editor: Luca Pattavina
In the past years, the study of neutrino and Dark Matter (DM) properties has risen a lot of interest in the Particle and Astroparticle physics communities. The recent instrumental and computational advancements made possible the discovery of some fundamental properties of these key constituents of our Universe. Hopefully, in the next 5-10 years the most important open questions in neutrino and DM physics will be addressed, as for example which is the mass and nature of neutrinos, or what is Dark Matter made of.
Since the proposition, in the early 80's, of low-temperature detectors for astroparticle physics applications, there have been enormous technological advancements. This experimental technique led to the realization of ultra-low threshold detectors, reaching eV-scales, but also the flawless operation of large arrays of ton-scale size. Nowadays cryogenic detectors are considered a key technology for next-generation neutrino and DM experiments, given their potential and their broad range of applications. Direct and indirect neutrino mass measurements, sterile neutrino searches as well as astrophysical neutrino observatories are within the reach of low-temperature detectors. In addition, the current survey of DM mass has currently spanned about 3 orders of magnitude, with still no discovery. Recently, these detectors were also proposed as Supernova neutrino observatories thanks to the previously mentioned achievements. In this Focus Point, we are aiming at highlighting the great potential of this experimental technique. In particular, we will focus on some technical aspects that include (but it is not limited to): realization of multi-purpose experiments for DM and neutrinoless double-beta decay studies, innovative particle discrimination techniques at low and ultra-low energies, how to extend the physics reach of currently running DM experiments to the newly expanding Coherent Elastic Neutrino-nucleus Scattering (CEvNS) sector, but also new energy calibration techniques at low and ultra-low energies.
EPJ Plus Focus Point Issue: Focus Point on Higher Derivatives in Quantum Gravity: Theory, Tests, Phenomenology
- Published on 07 April 2022
The quantization of General Relativity via standard perturbative quantum field theory results in a quantum theory of gravity which is perturbatively non-renormalizable. This caused a proliferation of approaches to quantum gravity, based on different assumptions, ideas, and quantization methods. However, within many of these approaches the Einstein-Hilbert action is expected to be complemented by higher-derivative operators. In the framework of quadratic gravity, these higher-order terms are crucial to make gravity renormalizable and asymptotically free; in string theory infinitely many of these arise in the form of “corrections”; in non-local gravity infinitely many derivatives are introduced at the level of the bare action to achieve both renormalizability and perturbative unitarity; in asymptotically safe gravity and in the spin-foam approach to quantum gravity a similar structure is expected to emerge at the level of the quantum effective action. Higher derivatives are also key in the framework of effective field theory, whose results ought to be matched by all approaches to quantum gravity. Last but not least, higher derivatives could impact the phenomenology of black holes, the wave form of gravitational waves, and the early-universe cosmology.
EPJ Plus Focus Point Issue: Citizen science for physics: From Education and Outreach to Crowdsourcing fundamental research
- Published on 31 January 2022
Citizen Science encompasses a broad range of activities, from science education and outreach to the actual harnessing of crowdsourcing to conduct state-of-the-art research in all sciences.
The present focus point is intended as both a review and advancement of current and future such activities in the field of core physics and related disciplines, as covered in the journal’s aims-and-scope. In particular, this article collection wishes to thoroughly explore - and act as incentive to foster - the contribution of citizen science to advancing science and how to design ongoing and future research projects to this aim.