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| 2. |
- Abele, H., et al.
(författare)
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Particle physics at the European Spallation Source
- 2023
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Ingår i: Physics reports. - : Elsevier. - 0370-1573 .- 1873-6270. ; 1023, s. 1-84
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Forskningsöversikt (refereegranskat)abstract
- Presently under construction in Lund, Sweden, the European Spallation Source (ESS) will be the world’s brightest neutron source. As such, it has the potential for a particle physics program with a unique reach and which is complementary to that available at other facilities. This paper describes proposed particle physics activities for the ESS. These encompass the exploitation of both the neutrons and neutrinos produced at the ESS for high precision (sensitivity) measurements (searches).
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| 3. |
- Beiming, Christoffer, et al.
(författare)
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Phenomenological mass model for exotic hadrons and predictions for masses of non-strange dibaryons as hexaquarks
- 2022
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Ingår i: Nuclear Physics B. - : Elsevier BV. - 0550-3213 .- 1873-1562. ; 974, s. 115616-
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Tidskriftsartikel (refereegranskat)abstract
- We investigate the mass spectra of exotic hadrons known as hexaquarks in the form of dibaryons. We use a phenomenological model based on an extended version of the Giirsey-Radicati mass formula for hadrons to include non-charmed baryons, charmed baryons, and non-strange dibaryons to be able to predict masses of potential dibaryon states. We perform six numerical fits of this model to input data for three different sets of masses of baryons and dibaryons. We find that the model can fit some of the data sets well, especially the sets including charmed baryons and non-strange dibaryons, and observe that the predicted mass of one of the dibaryons is close to the measured mass of the observed hexaquark candidate d * (2380) reported by the WASA-at-COSY experiment. The predicted mass of the deuteron is slightly larger than its measured mass. Finally, for the data sets including charmed baryon and non-strange dibaryon masses, we find that the predicted masses of potential dibaryon states are all in the range from 1900 MeV to 3700 MeV.
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| 4. |
- Blennow, Mattias, 1980-, et al.
(författare)
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A combined study of source, detector and matter non-standard neutrino interactions at DUNE
- 2016
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Ingår i: Journal of High Energy Physics (JHEP). - : Springer. - 1126-6708 .- 1029-8479. ; 2016:8
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Tidskriftsartikel (refereegranskat)abstract
- We simultaneously investigate source, detector and matter non-standard neutrino interactions at the proposed DUNE experiment. Our analysis is performed using a Markov Chain Monte Carlo exploring the full parameter space. We find that the sensitivity of DUNE to the standard oscillation parameters is worsened due to the presence of non-standard neutrino interactions. In particular, there are degenerate solutions in the leptonic mixing angle θ23 and the Dirac CP-violating phase δ. We also compute the expected sensitivities at DUNE to the non-standard interaction parameters. We find that the sensitivities to the matter non-standard interaction parameters are substantially stronger than the current bounds (up to a factor of about 15). Furthermore, we discuss correlations between the source/detector and matter non-standard interaction parameters and find a degenerate solution in θ23. Finally, we explore the effect of statistics on our results.
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| 5. |
- Blennow, Mattias, 1980-, et al.
(författare)
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Probing lepton flavor models at future neutrino experiments
- 2020
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Ingår i: Physical Review D. - : American Physical Society (APS). - 2470-0010 .- 2470-0029. ; 102:11
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Tidskriftsartikel (refereegranskat)abstract
- Non-Abelian discrete symmetries provide an interesting opportunity to address the flavor puzzle in the lepton sector. However, the number of currently viable models based on such symmetries is rather large. High-precision measurements of the leptonic mixing parameters by future neutrino experiments, including ESSnuSB, T2HK, DUNE, and JUNO, will be crucial to test such models. We show that the complementarity among these experiments offers a powerful tool for narrowing down this broad class of lepton flavor models.
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| 6. |
- Blennow, Mattias, 1980-, et al.
(författare)
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Testing lepton flavor models at ESSnuSB
- 2020
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Ingår i: Journal of High Energy Physics (JHEP). - : Springer Nature. - 1126-6708 .- 1029-8479. ; :7
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Tidskriftsartikel (refereegranskat)abstract
- We review and investigate lepton flavor models, stemming from discrete non- Abelian flavor symmetries, described by one or two free model parameters. First, we confront eleven one- and seven two-parameter models with current results on leptonic mixing angles from global fits to neutrino oscillation data. We find that five of the one- and five of the two-parameter models survive the confrontation test at 3 sigma. Second, we investigate how these ten one- and two-parameter lepton flavor models may be discriminated at the proposed ESSnuSB experiment in Sweden. We show that the three one-parameter models that predict sin delta(CP) = 0 can be distinguished from those two that predict vertical bar sin delta(CP)vertical bar = 1 by at least 7 sigma. Finally, we find that three of the five one-parameter models can be excluded by at least 5 sigma and two of the one-parameter as well as at most two of the five two-parameter models can be excluded by at least 3 sigma with ESSnuSB if the true values of the leptonic mixing parameters remain close to the present best-fit values.
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| 7. |
- Burgman, A., et al.
(författare)
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The ESSnuSB Design Study: Overview and Future Prospects
- 2023
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Ingår i: Universe. - : MDPI. - 2218-1997. ; 9:8
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Forskningsöversikt (refereegranskat)abstract
- ESSnuSB is a design study for an experiment to measure the CP violation in the leptonic sector at the second neutrino oscillation maximum using a neutrino beam driven by the uniquely powerful ESS linear accelerator. The reduced impact of systematic errors on sensitivity at the second maximum allows for a very precise measurement of the CP violating parameter. This review describes the fundamental advantages of measurement at the second maximum, the necessary upgrades to the ESS linac in order to produce a neutrino beam, the near and far detector complexes, and the expected physics reach of the proposed ESSnuSB experiment, concluding with the near future developments aimed at the project realization.
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| 8. |
- Burgman, A., et al.
(författare)
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The European Spallation Source neutrino super-beam conceptual design report
- 2022
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Ingår i: The European Physical Journal Special Topics. - : Springer Nature. - 1951-6355 .- 1951-6401. ; 231:21, s. 3779-3955
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Forskningsöversikt (refereegranskat)abstract
- A design study, named ESSνSB for European Spallation Source neutrino Super Beam, has been carried out during the years 2018–2022 of how the 5 MW proton linear accelerator of the European Spallation Source under construction in Lund, Sweden, can be used to produce the world’s most intense long-baseline neutrino beam. The high beam intensity will allow for measuring the neutrino oscillations near the second oscillation maximum at which the CP violation signal is close to three times higher than at the first maximum, where other experiments measure. This will enable CP violation discovery in the leptonic sector for a wider range of values of the CP violating phase δCPδCP and, in particular, a higher precision measurement of δCPδCP. The present Conceptual Design Report describes the results of the design study of the required upgrade of the ESS linac, of the accumulator ring used to compress the linac pulses from 2.86 ms to 1.2 μs, and of the target station, where the 5 MW proton beam is used to produce the intense neutrino beam. It also presents the design of the near detector, which is used to monitor the neutrino beam as well as to measure neutrino cross sections, and of the large underground far detector located 360 km from ESS, where the magnitude of the oscillation appearance of νe from νμ is measured. The physics performance of the ESSνSB research facility has been evaluated demonstrating that after 10 years of data-taking, leptonic CP violation can be detected with more than 5 standard deviation significance over 70% of the range of values that the CP violation phase angle δCPδCP can take and that δCPδCP can be measured with a standard error less than 8° irrespective of the measured value of δCPδCP. These results demonstrate the uniquely high physics performance of the proposed ESSνSBESSνSB research facility.
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| 9. |
- Burgman, A., et al.
(författare)
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Updated physics performance of the ESSnuSB experiment
- 2021
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Ingår i: European Physical Journal C. - : Springer Nature. - 1434-6044 .- 1434-6052. ; 81:12
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we present the physics performance of the ESSnuSB experiment in the standard three flavor scenario using the updated neutrino flux calculated specifically for the ESSnuSB configuration and updated migration matrices for the far detector. Taking conservative systematic uncertainties corresponding to a normalization error of 5% for signal and 10% for background, we find that there is 10 sigma (13 sigma) CP violation discovery sensitivity for the baseline option of 540 km (360 km) at delta(CP) = +/- 90 degrees. The corresponding fraction of delta(CP )for which CP violation can be discovered at more than 5 sigma is 70%. Regarding CP precision measurements, the 1 sigma error associated with delta(CP )= 0 degrees is around 5 degrees and with delta(CP )= -90 degrees is around 14 degrees (7 degrees) for the baseline option of 540 km (360 km). For hierarchy sensitivity, one can have 3 sigma sensitivity for 540 km baseline except delta(CP) = +/- 90 degrees and 5 sigma sensitivity for 360 km baseline for all values of delta(CP). The octant of theta(23) can be determined at 30 for the values of: theta(23) > 51 degrees (theta(23) < 42 degrees and theta(23) > 49 degrees) for baseline of 540 km (360 km). Regarding measurement precision of the atmospheric mixing parameters, the allowed values at 3 sigma are: 40 degrees < theta(23) < 52 degrees (42 degrees < theta(23) < 51.5 degrees) and 2.485 x 10(-3) eV(2) < Delta(2)(m31) < 2.545 x 10(-3) eV(2) (2.49x 10(-3 ) eV(2) < Delta(2)(m31) < 2.54 x 10(-3) eV(2)) for the baseline of 540 km (360 km).
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| 10. |
- Choubey, Sandhya, et al.
(författare)
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Exploring invisible neutrino decay at ESSnuSB
- 2021
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Ingår i: Journal of High Energy Physics (JHEP). - : Springer Nature. - 1126-6708 .- 1029-8479. ; 2021:5
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Tidskriftsartikel (refereegranskat)abstract
- We explore invisible neutrino decay in which a heavy active neutrino state decays into a light sterile neutrino state and present a comparative analysis of two baseline options, 540 km and 360 km, for the ESSnuSB experimental setup. Our analysis shows that ESSnuSB can put a bound on the decay parameter tau (3)/m(3) = 2.64 (1.68) x 10(-11) s/eV for the baseline option of 360 (540) km at 3 sigma. The expected bound obtained for 360 km is slightly better than the corresponding one of DUNE for a charged current (CC) analysis. Furthermore, we show that the capability of ESSnuSB to discover decay, and to measure the decay parameter precisely, is better for the baseline option of 540 km than that of 360 km. Regarding effects of decay in delta (CP) measurements, we find that in general the CP violation discovery potential is better in the presence of decay. The change in CP precision is significant if one assumes decay in data but no decay in theory.
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