Quantum decoherence effects in neutrino oscillations at DUNE

In this work, we analyze quantum decoherence in neutrino oscillations considering the open quantum system framework and oscillations through matter for three-neutrino families. Taking the Deep Underground Neutrino Experiment as a case study, we performed sensitivity analyses for two neutrino flux configurations, finding sensitivity limits for the decoherence parameters. We also offer a physical interpretation for a new peak which arises at the ${\nu }_e$ appearance probability with decoherence. The sensitivity limits found for the decoherence parameters are ${\mathrm{\Gamma }}_{21}\le 1.2\times {10}^{-23}\mathrm{GeV}$ and ${\mathrm{\Gamma }}_{32}\le 7.7\times {10}^{-25}\mathrm{GeV}$ at 90% C.L.

Figure 1

Oscillation probabilities using ${\mathrm{\Gamma }}_{21}=5.1\times {10}^{-25}\mathrm{GeV}$ and ${\mathrm{\Gamma }}_{32}=8.9\times {10}^{-24}\mathrm{GeV}$ (solid line) compared with the standard case without decoherence (dashed line). The values of the oscillation parameters were set according to Table 1, and ${\mathrm{\Gamma }}_{31}$ was calculated according to Eqs. (5)–(7).

Figure 2

Eigenvalues (${\lambda }_i$, $i=1$, 2, 3) of the Hamiltonian in Eq. (9). We can see an indication of a resonance region at about $E\sim 10\mathrm{GeV}$.

Figure 3

Behavior of $C^{32}(\mu e)$ and the interference factor $I^{32}(\mu e)$ given by Eqs. (17) and (16), respectively.

Figure 4

Relative event rates defined in Eq. (20) setting ${\mathrm{\Gamma }}_{21}=5.1\times {10}^{-25}\mathrm{GeV}$, and ${\mathrm{\Gamma }}_{32}=8.9\times {10}^{-24}\mathrm{GeV}$, for each oscillation channel in the presence of decoherence.

Figure 5

Curves at 90% C.L. (dashed-dotted line) and $3\sigma$ C.L. (dashed line) for 2 DOF for the two decoherence parameters ${\mathrm{\Gamma }}_{21}$ and ${\mathrm{\Gamma }}_{32}$, considering the default flux given by Ref. [29].

Figure 6

Sensitivity limits for the default flux in Ref. [29] for the ${\mathrm{\Gamma }}_{32}$ (${\mathrm{\Gamma }}_{21}$) upper (lower) panel. The horizontal lines define 90% C.L. and $3\sigma$ C.L.

Figure 7

Relative deviations with respect to the ${\nu }_e$ appearance events without decoherence (${\mathrm{\Gamma }}_{32}=0$) for the HE flux from Ref. [30] (red line). For the event rates with decoherence, we considered ${\mathrm{\Gamma }}_{21}=5.1\times {10}^{-25}\mathrm{GeV}$, ${\mathrm{\Gamma }}_{31}=3.0\times {10}^{-25}\mathrm{GeV}$, and ${\mathrm{\Gamma }}_{32}=1.6\times {10}^{-24}\mathrm{GeV}$. We also present the relative deviations for the ${\nu }_e$ appearance events considering the default flux [29] for comparison (black dashed line).

Figure 8

Confidence level curves in the ${\mathrm{\Gamma }}_{32}\text{−}{\mathrm{\Gamma }}_{21}$ plane at 90% C.L. (dark dashed-dotted line) and $3\sigma$ C.L. (dark dashed line), considering the HE flux. The confidence level curves for the default flux (light colors) are also shown for comparison (see Fig. 5).

Figure 9

${\mathrm{\Gamma }}_{32}$ ${\chi }^2$ profile after minimizing over ${\mathrm{\Gamma }}_{21}$ for the results with the default flux (dashed line) from Ref. [29] and the ones with HE flux (full line) from Ref. [30]. The horizontal lines define 90% C.L. and $3\sigma$ C.L.