<p>NuMI Off-axis <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>ν</mi><mi>e</mi></msub></math> Appearance (NOvA) experiment is an ongoing long-baseline neutrino oscillation experiment. The primary channels of interest are the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>ν</mi><mi>e</mi></msub></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mover accent="true"><mi>ν</mi><mo stretchy="false">¯</mo></mover><mi>e</mi></msub></math> appearance, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>ν</mi><mi>μ</mi></msub></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mover accent="true"><mi>ν</mi><mo stretchy="false">¯</mo></mover><mi>μ</mi></msub></math> disappearance channels analyzed in the energy window <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>1</mn><mo>&lt;</mo><msub><mi>E</mi><mi>ν</mi></msub><mo>&lt;</mo><mn>4</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>. However, NOvA far detector sees nontrivial high-energy <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>ν</mi><mi>e</mi></msub></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mover accent="true"><mi>ν</mi><mo stretchy="false">¯</mo></mover><mi>e</mi></msub></math> events in the energy range <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>4</mn><mo>&lt;</mo><msub><mi>E</mi><mi>ν</mi></msub><mo>&lt;</mo><mn>20</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>. These high-energy events provide us with an opportunity to investigate the subleading new physics scenarios. In this context, we study the sensitivity of the NOvA experiment to constrain the nonstandard interaction (NSI) parameters and environmental decoherence parameters. We observe that by including high energy events (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>signal</mi><mo>+</mo><mtext>background</mtext></mrow></math>) the degeneracy around <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>ε</mi><mrow><mi>e</mi><mi>τ</mi></mrow></msub><mo>∼</mo><mn>1.6</mn></math> can be removed throughout the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>δ</mi><mrow><mi>C</mi><mi>P</mi></mrow></msub></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>δ</mi><mrow><mi>e</mi><mi>τ</mi></mrow></msub></math> range. Further, we examine the role of signal versus beam background events in removing this degeneracy. In addition, we constrain the decoherence parameter <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="normal">Γ</mi></math> considering events from <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>1</mn><mo>&lt;</mo><msub><mrow><mi>E</mi></mrow><mrow><mi>ν</mi></mrow></msub><mo>&lt;</mo><mn>20</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></mrow></math>. Later, assuming the presence of decoherence in nature we obtain the allowed regions in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>θ</mi><mn>23</mn></msub></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>δ</mi><mrow><mi>C</mi><mi>P</mi></mrow></msub></math> plane.</p>

India

Chinmay Bera

K.N. Deepthi

Probing new physics scenarios using high energy events at the NOvA far detector

Neutrino oscillation physics has entered the precision era and the potential forthcoming experiments Hyper-Kamiokande (T2HK / T2HKK), Deep Under-ground Neutrino Experiment (DUNE) and The European Spallation Source ν-Beam (ESSνSB ) project are expected to strengthen this endeavour in the future. In this paper we perform a comprehensive study of the octant, mass hierarchy and CP discovery sensitivities of T2HK / T2HKK, DUNE and ESSνSB project in their individual capacity. We present a comparative account of the probabilities at the respective baselines and explore in detail the physics issues which can cause the differences in the sensitivities among the various experiments. We also find out the optimal exposure required by these experiments for achieving 5σ hierarchy, octant sensitivity and to discover CP violation at 5σ for 60% values of <math><msub><mrow><mi>δ</mi></mrow><mrow><mi>C</mi><mi>P</mi></mrow></msub></math>, stand alone and in conjunction with the on going T2K and NOνA experiments. In addition, we study the hierarchy and CP sensitivities of DUNE and T2HK in combination with ESSνSB.

Kaustav Chakraborty

Srubabati Goswami

Spotlighting the sensitivities of Hyper-Kamiokande, DUNE and ESS Sb

One of the primary objectives of the Deep Underground Neutrino Experiment (DUNE) is to discover the leptonic CP violation and to identify its source. In this context, we study the impact of non-standard neutrino interactions (NSIs) on observing the CP violation signal at DUNE. We explore the impact of various parameter degeneracies introduced by non-zero NSI and identify which of these can influence the CP violation sensitivity and CP precision of DUNE, by considering NSI both in data and in theory. In particular, we study how the CP sensitivity of DUNE is affected because of the intrinsic hierarchy degeneracy which occurs when the diagonal NSI parameter <math><msub><mrow><mi>ϵ</mi></mrow><mrow><mi>e</mi><mi>e</mi></mrow></msub><mo>=</mo><mo>−</mo><mn>1</mn></math> and <math><msub><mrow><mi>δ</mi></mrow><mrow><mi>C</mi><mi>P</mi></mrow></msub><mo>=</mo><mo>±</mo><mn>90</mn><mi>°</mi></math>.

China

Newton Nath

Challenges posed by non-standard neutrino interactions in the determination of at DUNE

With the recent measurement of reactor mixing angle <math id="M1"><mrow><msub><mrow><mi>θ</mi></mrow><mrow><mn>13</mn></mrow></msub></mrow></math> the knowledge of neutrino oscillation parameters has improved significantly except the CP violating phase <math id="M2"><mrow><msub><mrow><mi>δ</mi></mrow><mrow><mi>C</mi><mi>P</mi></mrow></msub></mrow></math>, mass hierarchy, and the octant of the atmospheric mixing angle <math id="M3"><mrow><msub><mrow><mi>θ</mi></mrow><mrow><mn>23</mn></mrow></msub></mrow></math>. Many dedicated experiments are proposed to determine these parameters which may take at least 10 years from now to become operational. It is therefore very crucial to use the results from the existing experiments to see whether we can get even partial answers to these questions. In this paper we study the discovery potential of the ongoing NO<math id="M4"><mrow><mi>ν</mi></mrow></math>A and T2K experiments as well as the forthcoming T2HK experiment in addressing these questions. In particular, we evaluate the sensitivity of NO<math id="M5"><mrow><mi>ν</mi></mrow></math>A to determine neutrino mass hierarchy, octant degeneracy, and <math id="M6"><mrow><msub><mrow><mi>δ</mi></mrow><mrow><mi>C</mi><mi>P</mi></mrow></msub></mrow></math> after running for its scheduled period of 3 years in neutrino mode and 3 years in antineutrino mode. We then extend the analysis to understand the discovery potential if the experiments will run for (<math id="M7"><mn>5</mn><mi>ν</mi><mo>+</mo><mn>5</mn><mover><mrow><mi>ν</mi></mrow><mo>¯</mo></mover></math>) years and (<math id="M8"><mn>7</mn><mi>ν</mi><mo>+</mo><mn>3</mn><mover><mrow><mi>ν</mi></mrow><mo>¯</mo></mover></math>) years. We also show how the sensitivity improves when we combine the data from NO<math id="M9"><mrow><mi>ν</mi></mrow></math>A, T2K, and T2HK experiments with different combinations of run period. The CP violation sensitivity is marginal for T2K and NO<math id="M10"><mrow><mi>ν</mi></mrow></math>A experiments even for ten-year data taking of NO<math id="M11"><mrow><mi>ν</mi></mrow></math>A. T2HK has a significance above <math id="M12"><mn>5</mn><mi>σ</mi></math> for a fraction of two-fifths values of the <math id="M13"><mrow><msub><mrow><mi>δ</mi></mrow><mrow><mi>C</mi><mi>P</mi></mrow></msub></mrow></math> space. We also find that <math id="M14"><mrow><msub><mrow><mi>δ</mi></mrow><mrow><mi>C</mi><mi>P</mi></mrow></msub></mrow></math> can be determined to be better than 35°, 21°, and 9° for all values of <math id="M15"><mrow><msub><mrow><mi>δ</mi></mrow><mrow><mi>C</mi><mi>P</mi></mrow></msub></mrow></math> for T2K, NO<math id="M16"><mrow><mi>ν</mi></mrow></math>A, and T2HK respectively.