Using two different approaches, we perform detailed calculations of the one-loop (Next-to-Leading Order (
NLO
)) electroweak radiative corrections to the parity violating
e
−
e
−
→
e
−
e
−
(γ) ...scattering asymmetry. First approach, more classical, relies on calculations “by hand” with reasonable approximations, second approach relies on program packages FeynArts, FormCalc, LoopTools, and FORM. The detailed numerical analysis of the various contributions is provided for a wide range of energies relevant for the ultraprecise 11 GeV MOLLER experiment planned at the JLab, as well as future experiments at the International Linear Collider (
ILC
). The numerical results obtained within the on-shell renormalization scheme using two different sets of renormalization conditions are in excellent agreement. We also calculate the total
NLO
correction in the Constrained Differential Renormalization (
CDR
) scheme. Analysis of the results, along with the increasing experimental precision, shows that it is feasible that the corrections at the Next-to-Next-to-Leading Order (
NNLO
) level may be important for the next generation of experiments.
In this article we describe the background challenges for the CUORE experiment posed by surface contamination of inert detector materials such as copper, and present three techniques explored to ...mitigate these backgrounds. Using data from a dedicated test apparatus constructed to validate and compare these techniques we demonstrate that copper surface contamination levels better than 10−7- 10−8 Bq/cm2 are achieved for 238U and 232Th. If these levels are reproduced in the final CUORE apparatus the projected 90% C.L. upper limit on the number of background counts in the region of interest is 0.02–0.03 counts/keV/kg/y depending on the adopted mitigation technique.
Neutrinoless double beta decay (
0
ν
β
β
) is one of the most sensitive probes for physics beyond the Standard Model, providing unique information on the nature of neutrinos. In this paper we review ...the status and outlook for bolometric
0
ν
β
β
decay searches. We summarize recent advances in background suppression demonstrated using bolometers with simultaneous readout of heat and light signals. We simulate several configurations of a future CUORE-like bolometer array which would utilize these improvements and present the sensitivity reach of a hypothetical next-generation bolometric
0
ν
β
β
experiment. We demonstrate that a bolometric experiment with the isotope mass of about 1 ton is capable of reaching the sensitivity to the effective Majorana neutrino mass (
|
m
e
e
|
) of order 10–20 meV, thus completely exploring the so-called inverted neutrino mass hierarchy region. We highlight the main challenges and identify priorities for an R&D program addressing them.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Neutrinoless double beta decay (0νββ) is a yet unobserved nuclear process that would demonstrate Lepton number violation, a clear evidence of beyond standard model physics. The process two neutrino ...double beta decay (2νββ) is allowed by the standard model and has been measured in numerous experiments. In this Letter, we report a measurement of 2νββ decay half-life of 100Mo to the ground state of 100Ru of 7.07±0.02(stat)±0.11(syst)×1018 yr by the CUPID-Mo experiment. With a relative precision of ±1.6% this is the most precise measurement to date of a 2νββ decay rate in 100Mo. In addition, we constrain higher-order corrections to the spectral shape, which provides complementary nuclear structure information. We report a novel measurement of the shape factor ξ3,1=0.45±0.03(stat)±0.05(syst) based on a constraint on the ratio of higher-order terms from theory, which can be reliably calculated. This is compared to theoretical predictions for different nuclear models. Finally, we also extract the first value for the effective axial vector coupling constant obtained from a spectral shape study of 2νββ decay.
► Measurement of radioactive contaminations of TeO2 crystals for the CUORE experiment. ► Both bulk and surface contamination from 238U and 232Th decay chains is not found. ► The upper limits are ...calculated to be within the contract specification. ► An extrapolation to CUORE background from bulk and surface contamination is performed.
The CUORE Crystal Validation Runs (CCVRs) have been carried out since the end of 2008 at the Gran Sasso National Laboratories, in order to test the performance and the radiopurity of the TeO2 crystals produced at SICCAS (Shanghai Institute of Ceramics, Chinese Academy of Sciences) for the CUORE experiment. In this work the results of the first 5 validation runs are presented. Results have been obtained for bulk contaminations and surface contaminations from several nuclides. An extrapolation to the CUORE background has been performed.
Neutrinoless double-beta (0vββ) decay is a hypothesized lepton-number-violating process that offers the only known means of asserting the possible Majorana nature of neutrino mass. The Cryogenic ...Underground Observatory for Rare Events (CUORE) is an upcoming experiment designed to search for 0vββ decay of sup.130Te using an array of 988 TeO.sub.2 crystal bolometers operated at 10 mK. The detector will contain 206 kg of sup.130Te and have an average energy resolution of 5 keV; the projected 0vββ decay half-life sensitivity after five years of livetime is 1.6 x 10.sup.26 γ at 1σ (9.5 x 10.sup.25 γ at the 90% confidence level), which corresponds to an upper limit on the effective Majorana mass in the range 40-100 meV (50-130 meV). In this paper, we review the experimental techniques used in CUORE as well as its current status and anticipated physics reach.
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