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Martin-Luna, P., Gimeno, B., Gonzalez-Iglesias, D., Esperante, D., Blanch, C., Fuster-Martinez, N., et al. (2023). On the Magnetic Field of a Finite Solenoid. IEEE Trans. Magn., 59(4), 7000106–6pp.
Abstract: The magnetostatic field of a finite solenoid with infinitely thin walls carrying a dc current oriented in the azimuthal direction is calculated everywhere in space in terms of complete elliptic integrals by direct integration of the Biot-Savart law. The solution is particularized near the solenoid axis and in the midplane perpendicular to the axis obtaining expressions that agree with some typical approximations that are made in introductory courses of electromagnetism or in the technical literature. The range of validity of these approximations has been studied comparing them with the obtained general expression.
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Molina, R., & Oset, E. (2023). T-cS (2900) as a threshold effect from the interaction of the D* K *, D *(s)rho channels. Phys. Rev. D, 107(5), 056015–7pp.
Abstract: We look at the mass distribution of the D(S)(+)i Pi(-) In the B-0 ->(DDS+)-D-0 Pi(-)decay, where a peak has been observed in the region of the D (*) (s)rho, D* K* thresholds. By creating these two channels together with a D (0) in B-0 decay and letting them interact as coupled channels, we obtain a structure around their thresholds, short of producing a bound state, which leads to a peak in the D-S(+) Pi(-)mass distribution in the B-0 -> (DDS+)-D-0 Pi(-)decay. We conclude that the interaction between the D*K* and D (*) (s)rho is essential to produce the cusp structure that we associate to the recently seen Tcs(2900), and that its experimental width is mainly due to the decay width of the rho meson. The peak obtained together with a smooth background reproduces fairly well the experimental mass distribution observed in the B (0)-> (DDS+)-D-0 Pi(-) decay.
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Borja-Lloret, M., Barrientos, L., Bernabeu, J., Lacasta, C., Muñoz, E., Ros, A., et al. (2023). Influence of the background in Compton camera images for proton therapy treatment monitoring. Phys. Med. Biol., 68(14), 144001–16pp.
Abstract: Objective. Background events are one of the most relevant contributions to image degradation in Compton camera imaging for hadron therapy treatment monitoring. A study of the background and its contribution to image degradation is important to define future strategies to reduce the background in the system. Approach. In this simulation study, the percentage of different kinds of events and their contribution to the reconstructed image in a two-layer Compton camera have been evaluated. To this end, GATE v8.2 simulations of a proton beam impinging on a PMMA phantom have been carried out, for different proton beam energies and at different beam intensities. Main results. For a simulated Compton camera made of Lanthanum (III) Bromide monolithic crystals, coincidences caused by neutrons arriving from the phantom are the most common type of background produced by secondary radiations in the Compton camera, causing between 13% and 33% of the detected coincidences, depending on the beam energy. Results also show that random coincidences are a significant cause of image degradation at high beam intensities, and their influence in the reconstructed images is studied for values of the time coincidence windows from 500 ps to 100 ns. Significance. Results indicate the timing capabilities required to retrieve the fall-off position with good precision. Still, the noise observed in the image when no randoms are considered make us consider further background rejection methods.
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Gil-Dominguez, F., & Molina, R. (2023). Quark mass dependence of the low-lying charmed mesons at one loop in HH & chi; PT. Phys. Lett. B, 843, 137997–15pp.
Abstract: We study the light and heavy quark mass dependence of the low-lying charmed mesons in the framework of one-loop HH & chi; PT. The low energy constants are determined by analyzing the available lattice data from different LQCD simulations. Model selection tools are implemented to determine the relevant parameters as required by data with a higher precision. Discretization and other effects due to the charm quark mass setting are discussed.
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Real, D., & Calvo, D. (2023). Silicon Photomultipliers for Neutrino Telescopes. Universe, 9(7), 326–14pp.
Abstract: Neutrino astronomy has opened a new window to the extreme Universe, entering into a fruitful era built upon the success of neutrino telescopes, which have already given a new step forward in this novel and growing field by the first observation of steady point-like sources already achieved by IceCube. Neutrino telescopes equipped with Silicon PhotoMultipliers (SiPMs) will significantly increase in number, because of their excellent time resolution and the angular resolution, and will be in better condition to detect more steady sources as well as the unexpected. The use of SiPMs represents a challenge to the acquisition electronics because of the fast signals as well as the high levels of dark noise produced by SiPMs. The acquisition electronics need to include a noise rejection scheme by implementing a coincidence filter between channels. This work discusses the advantages and disadvantages of using SiPMs for the next generation of neutrino telescopes, focusing on the possible developments that could help for their adoption in the near future.
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Garcia-Barcelo, J. M., Melcon, A. A., Diaz-Morcillo, A., Gimeno, B., Lozano-Guerrero, A. J., Monzi-Cabrera, J., et al. (2023). Methods and restrictions to increase the volume of resonant rectangular-section haloscopes for detecting dark matter axions. J. High Energy Phys., 08(8), 098–37pp.
Abstract: Haloscopes are resonant cavities that serve as detectors of dark matter axions when they are immersed in a strong static magnetic field. In order to increase the volume and improve space compatibility with dipole or solenoid magnets for axion searches, various haloscope design techniques for rectangular geometries are discussed in this study. The volume limits of two types of haloscopes are explored: those based on single cavities and those based on multicavities. In both cases, possibilities for increasing the volume of long and/or tall structures are presented. For multicavities, 1D geometries are explored to optimise the space in the magnets. Also, 2D and 3D geometries are introduced as a first step in laying the foundations for the development of these kinds of topologies. The results prove the usefulness of the developed methods, evidencing the ample room for improvement in rectangular haloscope designs nowadays. A factor of three orders of magnitude improvement in volume compared with a single cavity based on the WR-90 standard waveguide is obtained with the design of a long and tall single cavity. Similar procedures have been applied for long and tall multicavities. Experimental measurements are shown for prototypes based on tall multicavities and 2D structures, demonstrating the feasibility of using these types of geometries to increase the volume of real haloscopes.
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Tortajada, S., Albiol, F., Caballero, L., Albiol, A., & Leganes-Nieto, J. L. (2023). A portable geometry-independent tomographic system for gamma-ray, a next generation of nuclear waste characterization. Sci Rep, 13(1), 12284–10pp.
Abstract: One of the main activities of the nuclear industry is the characterisation of radioactive waste based on the detection of gamma radiation. Large volumes of radioactive waste are classified according to their average activity, but often the radioactivity exceeds the maximum allowed by regulators in specific parts of the bulk. In addition, the detection of the radiation is currently based on static detection systems where the geometry of the bulk is fixed and well known. Furthermore, these systems are not portable and depend on the transport of waste to the places where the detection systems are located. However, there are situations where the geometry varies and where moving waste is complex. This is especially true in compromised situations.We present a new model for nuclear waste management based on a portable and geometry-independent tomographic system for three-dimensional image reconstruction for gamma radiation detection. The system relies on a combination of a gamma radiation camera and a visible camera that allows to visualise radioactivity using augmented reality and artificial computer vision techniques. This novel tomographic system has the potential to be a disruptive innovation in the nuclear industry for nuclear waste management.
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Wang, D. (2023). Finslerian Universe May Reconcile Tensions Between High and Low Redshift Probes. Int. J. Theor. Phys., 62(8), 184–11pp.
Abstract: To reconcile the current tensions between high and low redshift observations, we perform the first constraints on the Finslerian cosmological models including the effective dark matter and dark energy components. We find that all the four Finslerian models could alleviate effectively the Hubble constant (H-0) tension and the amplitude of the root-mean-square density fluctu-ations (s(8)) tension between the Planck measurements and the local Universe observations at the 68% confidence level. The addition of a massless sterile neutrino and a varying total mass of active neutrinos to the base Finslerian two-parameter model, respectively, reduces the H-0 tension from 3.4s to 1.9s and alleviates the s8 tension better than the other three Finslerian models. Computing the Bayesian evidence, with respect to ACDM model, our analysis shows a weak preference for the base Finslerian model and moderate preferences for its three one-parameter extensions. Based on the model-independent Gaussian Processes, we propose a new linear relation which can describe the current redshift space distortions data very well. Using the most stringent constraints we can provide, we have also obtained the limits of typical model parameters for three one-parameter extensional models.
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Real, D., Calvo, D., Zornoza, J. D., & Manzaneda, M. (2023). White Rabbit Expansion Board: Design, Architecture, and Signal Integrity Simulations. Electronics, 12(16), 3394–16pp.
Abstract: The White Rabbit protocol allows synchronization and communication via an optical link in an integrated, modular, and scalable manner. It provides a solution to those applications that have very demanding requirements in terms of synchronization. Field-programmable gate arrays are used to implement the protocol; additionally, special hardware is needed to provide the necessary clock signals used by the dual-mixer time difference for precise phase measurement. In the present work, an expansion board that allows for White Rabbit functionality is presented. The expansion board contains the oscillators required by the White Rabbit protocol, one running at 125 MHz and another at 124.922 MHZ. The architecture of this board includes two oscillator systems for tests and comparison. One is based on VCOs and another on crystal oscillators running at the desired frequencies. In addition, it incorporates a temperature sensor, from where the medium access control address is extracted, an electrically erasable programmable read-only memory, a pulse-per-second output, and a USB UART to access the White Rabbit IP core at the field-programmable gate array. Finally, to ensure the quality of the layout design and guarantee the level of synchronization desired, the results of the power and signal integrity simulations are also presented.
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Cosme, C., Figueroa, D. G., & Loayza, N. (2023). Gravitational wave production from preheating with trilinear interactions. J. Cosmol. Astropart. Phys., 05(5), 023–30pp.
Abstract: We investigate the production of gravitational waves (GWs) during preheating with monomial/polynomial inflationary potentials, considering a trilinear coupling & phi;x2 between a singlet inflaton & phi; and a daughter scalar field x. For sufficiently large couplings, the trilinear interaction leads to an exponential production of x particles and, as a result, a large stochastic GW background (SGWB) is generated throughout the process. We study the linear and non-linear dynamics of preheating with lattice simulations, following the production of GWs through all relevant stages. We find that large couplings lead to SGWBs with amplitudes today that can reach up to h2 �(0) GW <^> 5 & BULL; 10-9. These backgrounds are however peaked at high frequencies fp > 5 & BULL; 106 Hz, which makes them undetectable by current/planned GW observatories. As the amount of GWs produced is in any case remarkable, we discuss the prospects for probing the SGWB indirectly by using constraints on the effective number of relativistic species in the universe Neff.
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