Physics

The CUPID-Mo experiment, currently taking data at the Laboratoire Souterrain de Modane (France), is a demonstrator for CUPID, the next-generation upgrade of the first ton-scale cryogenic 0νββ-search, CUORE. The experiment is searching for 0νββ decay of 100Mo with an array of 20 enriched ~0.2 kg Li2MoO4 crystals. The detectors are operated deep under the Frejus mountain at a depth of 4800 m.w.e. in a dilution refrigerator at ~20 mK. They are complemented by cryogenic Ge light detectors allowing us to distinguish alpha from beta/gamma events by the detection of both heat and scintillation light signals. With a bolometric performance of ~ 7 keV energy resolution (FWHM) at 2615 keV, full alpha-to-beta/gamma separation and excellent radio-purity levels, we operate in the background free regime. For the present analysis, we consider more than one year of data acquired between March 2019 and April 2020. With 2.17 kg x yr of exposure and a high analysis efficiency of ~ 90%, we are able to set a new world leading limit for 0νββ decay of 100Mo. In this seminar, I will present the details of the analysis, the new limit of T1/2 > 1.4 x 1024 yr at 90% c.i. and I will conclude with an outlook on the data taken up to the end of CUPID-Mo operations in July 2020 and further upcoming analyses.

SNO+ is a multi-purpose, low background liquid scintillator detector located in the SNOLAB facility. This talk will present our progress towards the main goal of SNO+: probing the mass and nature of neutrinos through a search for neutrino less double beta decay. By loading large amounts of natural tellurium into a homogeneous liquid scintillator detector SNO+ is pioneering an affordable and extendable approach to this rare decay search with the isotope 130Te. I will also discuss other physics reach of SNO+ including reactor, solar and supernova neutrinos and invisible nucleon decay. I will present the results for previous water phase operations and the current status of scintillator filling, tellurium plant preparation and background studies.

What factors drive the growth and decay of a pandemic? Can a study of community differences (in demographics, settlement, mobility, weather, and epidemic history) allow these factors to be identified? Has “herd immunity” to COVID-19 been reached anywhere? What are the best steps to manage/avoid future outbreaks in each community?  We analyzed the entire set of local COVID-19 epidemics in the United States; a broad selection of demographic, population density, climate factors, and local mobility data, in order to address these questions. What we found will surprise you! (based on arXiv:2007.00159)

The searches for solving the greatest mysteries of our Universe require ultra-sensitive detectors and an extreme control of the environment and the background in order to detect a rare signal. Over the last decades, technologies have reached such unprecedented sensitivity levels that never-before-seen background signals must be considered. In this talk I will give an overview of the requirements for low background detection and what are the current R&D effortsfor developing new cutting-edge technologies in order to address the common challenges of experiments and for pushing the limits of detector performance.

The discovery of gravitational wave signals from merger events of massive binary-black-hole (BBH) systems have prompted a renewed debate in the scientific community about the existence of primordial black holes (PBHs) of O(1-100) solar masses. These objects may have formed in the early Universe and could constitute a significant portion of the elusive dark matter that, according to standard cosmology, makes up the majority of the matter content in the universe. I will review the most recent developments of this field, with focus on multi-messenger prospects of detection. In the first part of the talk, I will present the prospects of discovery for both a hypothetical PBH population and the guaranteed population of astrophysical isolated black holes in our Galaxy, based on the radio and X-ray emission from the interstellar gas that is being accreted onto them (the “shiny dresses”). A future detection will be possible thanks to the expected performance of forthcoming radio facilities such as SKA and ngVLA. Then, I will turn my attention to scenarios where primordial black holes constitute a sub-dominant component of the dark matter, and study the impact of dark matter mini-spikes that are expected to form around them (the “dark dresses”) on several observables. In this context, I will first present an updated computation of the PBH merger rate as a function of DM fraction and redshift that takes into account the impact of the dark dresses. Then, I will discuss the observational prospects of these dresses in binary systems composed of a stellar-mass and an intermediate-mass black hole: I will show a novel calculation of the dephasing of the gravitational waveform induced by the DM spike, potentially detectable with the LISA space interferometer.DARK AND SHINY DRESSES AROUND BLACK HOLES DANIELE GAGGERO (UAM)July 6, 2020 Zoom Line: https://laurentian.zoom.us/j/92591146494