Search

Your search keyword '"Ohlsson, Tommy"' showing total 12 results
Start Over Author "Ohlsson, Tommy" Publication Year Range Last 3 years
12 results on '"Ohlsson, Tommy"'

1. Revisiting series expansions of neutrino oscillation and decay probabilities in matter

Author

Grönroos, Jesper, Ohlsson, Tommy, and Vihonen, Sampsa

Subjects
High Energy Physics - Phenomenology, High Energy Physics - Experiment, High Energy Physics - Theory
Abstract

We present analytic expressions for three-flavor neutrino oscillations in presence of invisible neutrino decay and matter effects. Using the well-known Cayley-Hamilton formalism, the leading-order terms are derived for oscillation probabilities in all major channels assuming the neutrino mass eigenstate $\nu_3$ to decay into sterile neutrinos. Our work extends and complements previous studies utilizing the Cayley-Hamilton theorem, providing the series expansions for $\nu_e \rightarrow \nu_e$, $\nu_e \rightarrow \nu_\mu$, $\nu_e \rightarrow \nu_\tau$, $\nu_\mu \rightarrow \nu_\mu$, $\nu_\mu \rightarrow \nu_\tau$ and $\nu_\tau \rightarrow \nu_\tau$. The accuracy of the analytical formulas is investigated by comparing the results with numerically calculated probabilities. We also comment on the implications on unitarity violation., Comment: 18 pages, 6 figures and 1 table. Comments are welcome!

Published
2024

2. Proton decay

Author

Ohlsson, Tommy

Subjects
High Energy Physics - Phenomenology, High Energy Physics - Experiment
Abstract

Proton decay is a hypothetical form of particle decay in which protons are assumed to decay into lighter particles. This form of decay has yet to be detected. In this contribution to the proceedings of Neutrino 2022, we review the current status of proton decay, covering both experimental results and theoretical models, including their predictions., Comment: 8 pages, 7 figures, REVTeX 4.2. Invited plenary talk presented at the XXXth International Conference on Neutrino Physics and Astrophysics (Neutrino 2022), (virtual) Seoul, Republic of Korea, June 4, 2022. Final version published in Nucl. Phys. B

Published
2023
Full Text
View/download PDF

3. One-Loop Matching Conditions in Neutrino Effective Theory

Author

Ohlsson, Tommy and Pernow, Marcus

Subjects
High Energy Physics - Phenomenology
Abstract

We investigate matching conditions and threshold corrections between full and effective theories based on the type I seesaw mechanism. In general, using an intuitive Feynman diagrammatical approach, we compute the amplitudes before and after integrating out heavy right-handed neutrinos at the matching scale. In particular, we derive the one-loop matching conditions between the full and the effective theories. The matching conditions of the parameters are influenced by one-loop corrections to the corresponding vertices as well as wave function corrections for the Higgs and the lepton fields. Our results are comparable to earlier results based on a functional approach., Comment: 38 pages, 19 figures. Final version published in Nucl. Phys. B

Published
2022
Full Text
View/download PDF

7. Particle physics at the European Spallation Source

Author

Abele, H., Blennow, Malin, Bohm, Christian, Dunne, Katherine, Meirose, Bernhard, Milstead, David A., Ohlsson, Tommy, Silverstein, Samuel B., Yiu, Sze-Chun, Zou, Y., Abele, H., Blennow, Malin, Bohm, Christian, Dunne, Katherine, Meirose, Bernhard, Milstead, David A., Ohlsson, Tommy, Silverstein, Samuel B., Yiu, Sze-Chun, and Zou, Y.

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).

Published
2023
Full Text
View/download PDF

8. The ESSnuSB Design Study : Overview and Future Prospects

Author

Alekou, A., Blennow, Mattias, Choubey, Sandhya, Ohlsson, Tommy, Zou, Y., et al., Alekou, A., Blennow, Mattias, Choubey, Sandhya, Ohlsson, Tommy, Zou, Y., and et al.

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., QC 20230920

Published
2023
Full Text
View/download PDF

9. BSM and Neutrinos_Proton decay

Author

Ohlsson, Tommy

Subjects
Physics::Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, High Energy Physics::Phenomenology, High Energy Physics::Experiment
Abstract

Plenary Talk from Neutrino 2022

Published
2022
Full Text
View/download PDF

11. Phenomenological mass model for exotic hadrons and predictions for masses of non-strange dibaryons as hexaquarks

Author

Beiming, Christoffer, Grönroos, Jesper, Ohlsson, Tommy, Beiming, Christoffer, Grönroos, Jesper, and Ohlsson, Tommy

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., QC 20211230

Published
2022
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results