CUORE

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The Cryogenic Underground Observatory for Rare Events (CUORE) is a particle physics facility located at the Laboratori Nazionali del Gran Sasso in Italy. It uses tellurium crystals in a bolometer-thermistor setup to observe 130Te beta decays; 130Te is a relatively abundant isotope of the element tellurium. By examining the endpoint of the double beta decay energy spectrum, CUORE looks for double beta decays that don't produce any neutrinos, a process known as neutrinoless double beta decay (0νββ). These events would appear as a single, very narrow peak at the energy spectrum endpoint as, unlike in ordinary double beta decay, there are no neutrinos to carry away part of the binding energy difference between the initial and final nuclei. Observing such decays would mean that neutrinos are their own antiparticles, and are thus Majorana fermions.

The CUORE detector will consist of an array of 988 tellurium dioxide (TeO2) crystals, serving as bolometric detectors and as the source of neutrinoless double beta decay. The crystals will arranged into 19 towers and cooled in a large dilution refrigerator to a temperature of 10 mK, where they have such a small heat capacity that the energy deposited by individual particles in the crystals produces a temporary, measurable rise its temperature. The temperature pulses are used to reconstruct an energy spectrum of the interactions in the crystals, and the spectrum is then inspected for a small peak at 2527 keV, the amount of energy that would be released in a neutrinoless double beta decay event in 130Te. The detector and cryostat are surrounded by extensive lead shielding, including several tons of low-radioactivity lead recovered from an ancient shipwreck.[1]

The CUORE collaboration involves physicists from several countries including the US and Italy,[2] and has published papers about the performance of various parts of the detector and simulation.[3] A prototype detector, CUORICINO, proved the construction concepts and the attainability of low background levels.[4] Results from a single tower (CUORE-0) were published in 2014;[5] results from the full detector are expected around 2015.

CUORE is funded by the Istituto Nazionale di Fisica Nucleare (INFN) of Italy, the United States Department of Energy (DOE), and National Science Foundation (NSF) of the United States.

References[edit]

  1. ^ Nosengo, N. (2010). "Roman ingots to shield particle detector". Nature. doi:10.1038/news.2010.186.  edit
  2. ^ CUORE Collaboration. "Cuore - Institutions". Retrieved 2013-11-08. 
  3. ^ CUORE Collaboration. "Public List of Published Papers". Retrieved 2013-11-08. 
  4. ^ Andreotti, E. et al. (2011). "130Te neutrinoless double-beta decay with CUORICINO". Astroparticle Physics 34 (11): 822. doi:10.1016/j.astropartphys.2011.02.002.  edit
  5. ^ CUORE Collaboration (2014). "Initial performance of the CUORE-0 experiment". arXiv:1402.0922 [physics.ins-det].

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