Zhang, X., Xiao, Y. T., & Gimeno, B. (2020). Multipactor Suppression by a Resonant Static Magnetic Field on a Dielectric Surface. IEEE Trans. Electron Devices, 67(12), 5723–5728.
Abstract: In this article, we study the suppression of the multipactor phenomenon on a dielectric surface by a resonant static magnetic field. A homemade Monte Carlo algorithm is developed for multipactor simulations on a dielectric surface driven by two orthogonal radio frequency (RF) electric field components. When the static magnetic field is perpendicular to the tangential and normal RF electric fields, it is shown that if the normal electric field lags the tangential electric field by pi/2, the superposition of the normal and tangential electric fields will trigger a gyro-acceleration of the electron cloud and restrain the multipactor discharge effectively. By contrast, when the normal electric field is in advance of the tangential electric field by pi/2, the difference between the normal and tangential electric fields drives gyro-motion of the electron cloud. Consequently, two enhanced discharge zones are inevitable. The suppression effects of the resonant static magnetic field that is parallel to the tangential RF electric field or to the normal RF electric field are also presented.
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Zhai, Y. J., Giare, W., van de Bruck, C., Di Valentino, E., Mena, O., & Nunes, R. C. (2023). A consistent view of interacting dark energy from multiple CMB probes. J. Cosmol. Astropart. Phys., 07(7), 032–16pp.
Abstract: We analyze a cosmological model featuring an interaction between dark energy and dark matter in light of the measurements of the Cosmic Microwave Background released by three independent experiments: the most recent data by the Planck satellite and the Atacama Cosmology Telescope, and WMAP (9-year data). We show that different combinations of the datasets provide similar results, always favoring an interacting dark sector with a 95% C.L. significance in the majority of the cases. Remarkably, such a preference remains consistent when cross-checked through independent probes, while always yielding a value of the expansion rate H0 consistent with the local distance ladder measurements. We investigate the source of this preference by scrutinizing the angular power spectra of temperature and polarization anisotropies as measured by different experiments.
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ANTARES Collaboration(Aguilar, J. A. et al), Bigongiari, C., Emanuele, U., Gomez-Gonzalez, J. P., Hernandez-Rey, J. J., Mangano, S., et al. (2010). Measurement of the atmospheric muon flux with a 4 GeV threshold in the ANTARES neutrino telescope. Astropart Phys., 33(2), 86–90.
Abstract: A new method for the measurement of the muon flux in the deep-sea ANTARES neutrino telescope and its dependence on the depth is presented. The method is based oil the observation of coincidence signals in adjacent storeys of the detector. This yields an energy threshold of about 4 GeV. The main sources of optical background are the decay of K-40 and the bioluminescence in the sea water. The K-40 background is used to calibrate the efficiency of the photo-multiplier tubes.
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Yue, Z. et al, Algora, A., & Nacher, E. (2024). Magnetic moments of thallium isotopes in the vicinity of magic N=126. Phys. Lett. B, 849, 138452–7pp.
Abstract: The magnetic dipole moments (mu) of Tl-209(g)(N =128) and Tl-207(m)(N = 126) have been measured for the first time using the in -source laser resonance -ionization spectroscopy technique with the Laser Ion Source and Trap (LIST) at ISOLDE (CERN). The application of the LIST suppresses the usually overwhelming background of the isobaric francium isotopes and allows access to heavy thallium isotopes with >207. The self -consistent theory of finite Fermi systems based on the energy density functional by Fayans et al. well describes the N dependence of μfor 1/2(+) thallium ground states, as well as μfor the 11/2(-) isomeric states in europium, gold and thallium isotopes. The inclusion of particle-vibration coupling leads to a better agreement between the theory and experiment for mu(Tl-g , I-pi = 1/2(+)). It is shown that beyond mean-field contributions tocannot be neglected at least for thallium isotopes with I-pi = 1/2(+).
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Yoshida, T., Hagura, N., Umezu, R., Algora, A., Tain, J. L., Jordan, D., et al. (2011). Impact of TAGS Measurement on FP Decay Data and Decay Heat Calculations. J. Korean Phys. Soc., 59(2), 1543–1546.
Abstract: Nuclear level schemes are usually constructed from the high-resolution data of the gamma-ray transitions which immediately follow the beta-decay of their parents. It is recognized that this procedure may lead to the “pandemonium problem”. If we use the decay data suffering from the pandemonium problem for the decay heat calculations the beta-ray component will be overestimated and the gamma-ray component underestimated. The beta-feeding data obtained by the total absorption gamma-ray spectroscopy (TAGS) is proved to be free from this problem. In the case of the Japanese data base for the FP decay heat calculation, the theoretical values based on the gross theory of beta-decay are widely introduced to circumvent the pandemonium problem. The gross theory, however, is not good at describing any beta-transition exclusively concentrating to a single level in the daughter nucleus. The TAGS method is also proved to be able to save this situation. Further, we have to change our comprehension over the currently published decay schemes.
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Yang, W. Q., Pan, S., Di Valentino, E., Mena, O., & Melchiorri, A. (2021). 2021-H-0 odyssey: closed, phantom and interacting dark energy cosmologies. J. Cosmol. Astropart. Phys., 10(10), 008–21pp.
Abstract: Up-to-date cosmological data analyses have shown that (sigma) a closed universe is preferred by the Planck data at more than 99% CL, and (b) interacting scenarios offer a very compelling solution to the Hubble constant tension. In light of these two recent appealing scenarios, we consider here an interacting dark matter-dark energy model with a non-zero spatial curvature component and a freely varying dark energy equation of state in both the quintessential and phantom regimes. When considering Cosmic Microwave Background data only, a phantom and closed universe can perfectly alleviate the Hubble tension, without the necessity of a coupling among the dark sectors. Accounting for other possible cosmological observations compromises the viability of this very attractive scenario as a global solution to current cosmological tensions, either by spoiling its effectiveness concerning the H-0 problem, as in the case of Supernovae Ia data, or by introducing a strong disagreement in the preferred value of the spatial curvature, as in the case of Baryon Acoustic Oscillations.
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Yamamoto, H. (2021). The International Linear Collider Project-Its Physics and Status. Symmetry-Basel, 13(4), 674–15pp.
Abstract: The discovery of Higgs particle has ushered in a new era of particle physics. Even though the list of members of the standard theory of particle physics is now complete, the shortcomings of the theory became ever more acute. It is generally considered that the best solution to the problems is an electron-positron collider that can study Higgs particle with high precision and high sensitivity; namely, a Higgs factory. Among a few candidates for Higgs factory, the International Linear Collider (ILC) is currently the most advanced in its program. In this article, we review the physics and the project status of the ILC including its energy expandability.
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Yamagata-Sekihara, J., Garcia-Recio, C., Nieves, J., Salcedo, L. L., & Tolos, L. (2016). Formation spectra of charmed meson-nucleus systems using an antiproton beam. Phys. Lett. B, 754, 26–32.
Abstract: We investigate the structure and formation of charmed meson--nucleus systems, with the aim of understanding the charmed meson-nucleon interactions and the properties of the charmed mesons in the nuclear medium. The (D) over bar mesic nuclei are of special interest, since they have tiny decay widths due to the absence of strong decays for the (D) over barN pair. Employing an effective model for the (D) over barN and DN interactions and solving the Klein-Gordon equation for (D) over bar and D in finite nuclei, we find that the D0-11B system has 1s and 2p mesic nuclear states and that the D0-11B system binds in a 1s state. In view of the forthcoming experiments by the PANDA and CBM Collaborations at the future FAIR facility and the J-PARC upgrade, we calculate the formation spectra of the [(D) over bar B--11] and [D-0-B-11] mesic nuclei for an antiproton beam on a C-12 target. Our results suggest that it is possible to observe the 2p D- mesic nuclear state with an appropriate experimental setup.
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Witte, S. J., Rosauro-Alcaraz, S., McDermott, S. D., & Poulin, V. (2020). Dark photon dark matter in the presence of inhomogeneous structure. J. High Energy Phys., 06(6), 35pp.
Abstract: Dark photon dark matter will resonantly convert into visible photons when the dark photon mass is equal to the plasma frequency of the ambient medium. In cosmological contexts, this transition leads to an extremely efficient, albeit short-lived, heating of the surrounding gas. Existing work in this field has been predominantly focused on understanding the implications of these resonant transitions in the limit that the plasma frequency of the Universe can be treated as being perfectly homogeneous, i.e. neglecting inhomogeneities in the electron number density. In this work we focus on the implications of heating from dark photon dark matter in the presence of inhomogeneous structure (which is particularly relevant for dark photons with masses in the range 10(-15) eV less than or similar to m(A ') less than or similar to 10(-12) eV), emphasizing both the importance of inhomogeneous energy injection, as well as the sensitivity of cosmological observations to the inhomogeneities themselves. More specifically, we derive modified constraints on dark photon dark matter from the Ly-alpha forest, and show that the presence of inhomogeneities allows one to extend constraints to masses outside of the range that would be obtainable in the homogeneous limit, while only slightly relaxing their strength. We then project sensitivity for near-future cosmological surveys that are hoping to measure the 21cm transition in neutral hydrogen prior to reionization, and demonstrate that these experiments will be extremely useful in improving sensitivity to masses near similar to 10(-14) eV, potentially by several orders of magnitude. Finally, we discuss implications for reionization, early star formation, and late-time y-type spectral distortions, and show that probes which are inherently sensitive to the inhomogeneous state of the Universe could resolve signatures unique to the light dark photon dark matter scenario, and thus offer a fantastic potential for a positive detection.
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CALICE Collaboration(White, A. et al), & Irles, A. (2023). Design, construction and commissioning of a technological prototype of a highly granular SiPM-on-tile scintillator-steel hadronic calorimeter. J. Instrum., 18(11), P11018–39pp.
Abstract: The CALICE collaboration is developing highly granular electromagnetic and hadronic calorimeters for detectors at future energy frontier electron-positron colliders. After successful tests of a physics prototype, a technological prototype of the Analog Hadron Calorimeter has been built, based on a design and construction techniques scalable to a collider detector. The prototype consists of a steel absorber structure and active layers of small scintillator tiles that are individually read out by directly coupled SiPMs. Each layer has an active area of 72 x 72 cm2 and a tile size of 3 x 3 cm2. With 38 active layers, the prototype has nearly 22, 000 readout channels, and its total thickness amounts to 4.4 nuclear interaction lengths. The dedicated readout electronics provide time stamping of each hit with an expected resolution of about 1 ns. The prototype was constructed in 2017 and commissioned in beam tests at DESY. It recorded muons, hadron showers and electron showers at different energies in test beams at CERN in 2018. In this paper, the design of the prototype, its construction and commissioning are described. The methods used to calibrate the detector are detailed, and the performance achieved in terms of uniformity and stability is presented.
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