Directional Dark Matter searches and the CYGNO/INITIUM project
by
1/1-1 - Aula "A. Rostagni"
Dipartimento di Fisica e Astronomia - Edificio Marzolo
Speaker: Elisabetta Baracchini
Affiliation: Gran Sasso Science Institute - L'Aquila
Date: November 9th, at 3 PM
Where: Aula Rostagni and YouTube streaming
Abstract: The importance of directly detect and experimentally probe the nature of Dark Matter (DM) is universally and incontrovertibly recognised as one of the most compelling tasks of today’s fundamental physics. Experimental direct DM searches have reached a level of maturity and complexity for which the detectors response to signal and the experiment backgrounds needs to be understood and controlled at unprecedented levels, in order to avoid the appearance of unexplained excesses. The measurement of the DM scattering directionality not only offers a powerful handle to deal with backgrounds (including neutrinos), but it grants an unique key for a positive unambiguous identification of a DM interaction by establishing its Galactic origin. The difficulty in measuring the direction of a WIMP-induced scattering resides in the very low momentum exchanged in the interaction, that for O(keV) nuclear recoils produces tracks of the order of nm in solids, um in liquids and mm in gaseous media. We will review the discovery potential of directional experimental approaches to detect and characterise WIMPs, and illustrate how this can also leap beyond the “Neutrino Fog” bound, actually promoting solar neutrinos from background to a signal with attractive physics cases. We will illustrate the main experimental techniques employed in the development of directional DM experiments and we will focus on the Gaseous Time Projection Chambers (TPCs), which currently represent the most mature approach to this problem. We will present in details the CYGNO/INITIUM project, an high precision 3D tracking TPC with optical readout for directional Dark Matter search and solar neutrino spectroscopy currently under development at Laboratori Nazionali del Gran Sasso. We will illustrate the commissioning and the underground operation of the 50 L prototype LIME, the largest developed so far by the collaboration, and its capability to measure and identify low energy nuclear and electron recoils. We will outline the design and prospects for the development of the already funded O(1) m3 demonstrator to be hosted in Hall F of LNGS and illustrate the physics reach of a possible future O(30) m3 experiment emerging from these developments. We will furthermore discuss the R&D results obtained by the collaboration towards the maximisation of the CYGNO potentialities, and in particular the recent demonstration of negative ion drift operation at atmospheric pressure with optical readout obtained in synergy with the ERC Consolidator Grant project INITIUM.
Elisabetta Baracchini is full professor and researcher at the Gran Sasso Science Institute in L'Aquila. She began her scientific activity with BaBar, one of the most advanced particle physics experiments for the study of the asymmetry between matter and antimatter on an electron-positron accelerator. She continued her career as a postdoctoral fellow and researcher for UC Irvine, the KEK laboratory in Tsukuba, and the University of Tokyo, at MEG, on a high-precision experiment on a fixed target to search for signals beyond the standard model, in which it expanded its know-how in the detection of charged particles in gas detectors.
Strengthened by the experience acquired in those years, she has shifted her attention to detectors for dark matter and neutrinos. In 2015 she received a Marie Słodowska-Curie Individual Fellowship for her original proposal for NITEC, a negative ion detector for directional searches for dark matter. Her innovative work with NITEC and her passion for this sector soon led to a leadership position in the international CYGNUS project and in the research and development studies for optically readable detectors, funded by INFN and CYGNUS-RD . The ERC Consolidator INITIUM (Innovative Negative Ion TIme projection chamber for Underground dark Matter searchers) project, for which it has just received a fund of around 2 million euros from the European Research Council of the European Union, represents the consolidation of all these recent activities in an innovative experiment for dark matter research.
Paride Paradisi
