المؤلفون: Nordberg, Markus, author, Liyanage, Shantha, author, Streit-Bianchi, Marilena, author

المصدر: Big Science, Innovation, and Societal Contributions : The Organisations and Collaborations in Big Science Experiments, 2024, ill.

الإتاحة: https://doi.org/10.1093/oso/9780198881193.003.0002Test

المؤلفون: M. Villani, M. Fabi, C. Grimani, F. Sabbatini, F. Dimiccoli, R. Dolesi, V. Ferroni, W.J. Weber

المصدر: Results in Physics, Vol 60, Iss , Pp 107638- (2024)

مصطلحات موضوعية: Instrumentation: Interferometers, (ISM:) cosmic rays, Elementary particles, Quantum diffraction, Physics, QC1-999

الوصف: The future Laser Interferometer Space Antenna (LISA) for gravitational wave detection in space and the precursor LISA Pathfinder missions rely on metal test masses (TMs) playing the role of free-falling geodesic-reference and interferometer end mirrors. Charge deposited on the TMs by high-energy particles of galactic and solar origin couples with stray electric fields thus perturbing the free-falling geodesic motion. In previous works it has been shown that sub-keV electrons play a relevant role for TM charging. In particular, electrons with energies below 100 eV show a wave-like behavior when impacting on the gold coatings of the TMs and electrode-housing (EH), the capacitive position sensor/actuator that surrounds the TMs. We aim at studying the effects of quantum diffraction of electrons on LISA Pathfinder and LISA TMs and EH gold lattice. We calculate the quantum diffraction probability of electrons with energies < 100 eV impinging on gold lattice from different directions by using the methods of quantum mechanics. The effects of electron quantum diffraction on LISA TM charging are reported here for the first time. This work is also of interest for the second-generation LISA-like space interferometers and for all space missions whose performance relies on free-falling metal test masses.

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S2211379724003218Test; https://doaj.org/toc/2211-3797Test

الوصول الحر: https://doaj.org/article/9ce5156361714be4a6b3382ff8b487e8Test

المؤلفون: Perov, Polievkt

المصدر: College of Arts & Sciences Faculty Works

مصطلحات موضوعية: elementary particles, quark, neutrino, nuclear reactions, beta-decay, Elementary Particles and Fields and String Theory, Nuclear, Physics

الوصف: On examples of different beta-decay reactions, we show that the neutrino-antineutrino pairs should be added as necessary reagents to the equations of the decay reactions where a neutrino or an antineutrino is among the products of the reaction. In our models, quarks and leptons are all made of basic fractional +-e/3 charges. Transfer of basic charges between reagents forms the products of the reaction. We suggest that there is no direct conversion of u-quark to d-quark and visa versa. Each transmutation involves a transfer of basic charges from a neutrino to a quark so the structure of remaining charges in the neutrino is a new quark and the quark receiving the charges is an electron or a positron. We suggest that a neutrino-antineutrino pair should be added as an essential reagent into the equation of the reaction of production of a deuteron out of two protons in the proton-proton chain which is an essential part of the fusion chain of reactions.

وصف الملف: application/pdf

العلاقة: https://dc.suffolk.edu/cas-faculty/24Test; https://dc.suffolk.edu/context/cas-faculty/article/1023/viewcontent/Perov_Neutrinos_Are_Reagents_In_Decay_Reactions_And_Proton_Neutron_Transmutations_031824.pdfTest

الإتاحة: https://dc.suffolk.edu/cas-faculty/24Test
https://dc.suffolk.edu/context/cas-faculty/article/1023/viewcontent/Perov_Neutrinos_Are_Reagents_In_Decay_Reactions_And_Proton_Neutron_Transmutations_031824.pdfTest

المؤلفون: Perov, Polievkt

المصدر: College of Arts & Sciences Faculty Works

مصطلحات موضوعية: elementary particles, electron, quarks, neutrinos, Elementary Particles and Fields and String Theory, Nuclear, Physics

الوصف: We consider a possible line of “elementary†particles as composite spinning structures made of just two basic elementary particles of charges + e/3 and -e/3. In considered structures, up to 3 basic charges can be on the axis of rotation and other charges can be in a revolving motion about the axis. In addition to the simplest structures of quarks, an electron and a neutral particle containing mostly one or no charges on the axis of rotation, suggested initially in [4], we analyze possible spatial structures of spinning composite particles having 2 or 3 charges on the axis of rotation. The net force on any charge that is on the axis of rotation must be zero. The net force on any charge revolving in circular orbits about the axis must be non-zero and be directed toward the axis of rotation. Considering that all the forces in the suggested structures are of EM origin, we calculated form factors of spatial arrangements of different spinning structures of the total charges of -e/3 (similar to a d-quark), +2e/3 (similar to a u-quark), -e (similar to an electron), and 0e (assumed to be neutrinos). All the considered structures but one have a non-zero angular momentum (spin) due to a rotational motion of particles and non-zero magnetic moments due to rotational motion of electric charges so they are fermions. One composite structure has a non-zero spin but zero electric charge and zero magnetic moment, so it is likely a boson.

وصف الملف: application/pdf

العلاقة: https://dc.suffolk.edu/cas-faculty/19Test; https://dc.suffolk.edu/context/cas-faculty/article/1019/viewcontent/Beyond_standard_model__form_factors_of_structures_of_quarks_and_neutrinos_as_composite_particles_version2_020324.pdfTest

الإتاحة: https://dc.suffolk.edu/cas-faculty/19Test
https://dc.suffolk.edu/context/cas-faculty/article/1019/viewcontent/Beyond_standard_model__form_factors_of_structures_of_quarks_and_neutrinos_as_composite_particles_version2_020324.pdfTest

المؤلفون: Lee, Kyle, Moult, Ian, Ringer, Felix, Waalewijn, Wouter J.

المصدر: Physics Faculty Publications

مصطلحات موضوعية: Algorithms, Classical and quantum gravitation, Elementary particle jets, Elementary particles, Energy, Factorization, Jets and jet substructure, Large hadron collider, Perturbation theory, Properties of hadrons, Matching, Mathematical analysis, Nonperturbative effects, Quantum chromodynamics, Quantum field theories, Quantum field theory, Quantum physics, Regular article - theoretical physics, Relativity theory, Renormalization group, String theory, Theoretical physics, Elementary Particles and Fields and String Theory, Physics

الوصف: The continued success of the jet substructure program will require widespread use of tracking information to enable increasingly precise measurements of a broader class of observables. The recent reformulation of jet substructure in terms of energy correlators has simplified the incorporation of universal non-perturbative matrix elements, so called “track functionsâ€, in jet substructure calculations. These advances make it timely to understand how these universal non-perturbative functions can be extracted from hadron collider data, which is complicated by the use jet algorithms. In this paper we introduce a new class of jet functions, which we call (semi-inclusive) track jet functions, which describe measurements of the track energy fraction in identified jets. These track jet functions can be matched onto the universal track functions, with perturbatively calculable matching coefficients that incorporate the jet algorithm dependence. We perform this matching, and present phenomenological results for the charged energy fraction in jets at the LHC and EIC/HERA at collinear next-to-leading logarithmic accuracy. We show that higher moments of the charged energy fraction directly exhibit non-linear Lorentzian renormalization group flows, allowing the study of these flows with collider data. Our factorization theorem enables the extraction of universal track functions from jet measurements, opening the door to their use for a precision jet substructure program.

وصف الملف: application/pdf

العلاقة: https://digitalcommons.odu.edu/physics_fac_pubs/833Test; https://digitalcommons.odu.edu/context/physics_fac_pubs/article/1835/viewcontent/Ringer_2024_AFormalismforExtractingTrackFunctionsfromJetMeasuresOCR.pdfTest

الإتاحة: https://doi.org/10.1007/JHEP01Test(2024)194
https://digitalcommons.odu.edu/physics_fac_pubs/833Test
https://digitalcommons.odu.edu/context/physics_fac_pubs/article/1835/viewcontent/Ringer_2024_AFormalismforExtractingTrackFunctionsfromJetMeasuresOCR.pdfTest

المؤلفون: Dimitris M. Christodoulou, Demosthenes Kazanas

المصدر: Astronomy, Vol 2, Iss 4, Pp 235-268 (2023)

مصطلحات موضوعية: atomic processes, cosmological parameters, cosmology: theory, early universe, elementary particles, galaxies: kinematics and dynamics, Astronomy, QB1-991

الوصف: Natural systems of units {Ui} need to be overhauled to include the dimensionless coupling constants {αUi} of the natural forces. Otherwise, they cannot quantify all the forces of nature in a unified manner. Thus, each force must furnish a system of units with at least one dimensional and one dimensionless constant. We revisit three natural systems of units (atomic, cosmological, and Planck). The Planck system is easier to rectify, and we do so in this work. The atomic system discounts {G,αG}, thus it cannot account for gravitation. The cosmological system discounts {h,αh}, thus it cannot account for quantum physics. Here, the symbols have their usual meanings; in particular, αG is the gravitational coupling constant and αh is Dirac’s fine-structure constant. The speed of light c and the impedance of free space Z0 are resistive properties imposed by the vacuum itself; thus, they must be present in all systems of units. The upgraded Planck system with fundamental units UPS:={c,Z0,G,αG,h,αh,…} describes all physical scales in the universe—it is nature’s system of units. As such, it reveals a number of properties, most of which have been encountered previously in seemingly disjoint parts of physics and some of which have been designated as mere coincidences. Based on the UPS results, which relate (sub)atomic scales to the Planck scale and the fine-structure constant to the Higgs field, we can state with confidence that no observed or measured physical properties are coincidental in this universe. Furthermore, we derive from first principles Koide’s K=2/3 enigmatic constant and additional analogous quark and vector boson constants. These are formal mathematical proofs that justify a posteriori the use of geometric means in deriving the quark/boson mass ladder. This ladder allows us to also calculate the Higgs couplings to the vector bosons and the Weinberg angle in terms of K only, and many of the “free” parameters of the Standard Model of particle physics were previously expected to be determined only from experiments.

وصف الملف: electronic resource

العلاقة: https://www.mdpi.com/2674-0346/2/4/17Test; https://doaj.org/toc/2674-0346Test

الوصول الحر: https://doaj.org/article/65602dc0386249a58af6b13bd2cef08aTest

المؤلفون: Nathan Walker, Tyler Parsotan, Davide Lazzati

المصدر: The Astrophysical Journal. 965(1)

مصطلحات موضوعية: Physics of Elementary Particles and Fields

الوصف: Long-duration gamma-ray bursts (LGRBs), thought to be produced during core-collapse supernovæ, may have a prominent neutron component in the outflow material. If present, neutrons can change how photons scatter in the outflow by reducing its opacity, thereby allowing the photons to decouple sooner than if there were no neutrons present. Understanding the details of this process could therefore allow us to probe the central engine of LGRBs, which is otherwise hidden. Here, we present results of the photospheric emission from an LGRB jet, using a combination of relativistic hydrodynamic simulations and radiative transfer post-processing using the Monte Carlo Radiation Transfer (MCRaT) code. We control the size of the neutron component in the jet material by varying the equilibrium electron fraction Ye, and we find that the presence of neutrons in the GRB fireball affects the Band parameters α and E0, while the picture with the β parameter is less clear. In particular, the break energy E0 is shifted to higher energies. Additionally, we find that increasing the size of the neutron component also increases the total radiated energy of the outflow across multiple viewing angles. Our results not only shed light on LGRBs, but are also relevant to short-duration gamma-ray bursts associated with binary neutron star mergers, due to the likelihood of a prominent neutron component in such systems.

الوصول الحر: https://ntrs.nasa.gov/citations/20240002751Test

المساهمون: Grace, R.

المصدر: Conference: 2. LAMPF workshop, Los Alamos, NM, USA, 19 Jul 1982

وصف الملف: Medium: ED; Size: Pages: 16

الوصول الحر: http://www.osti.gov/scitech/servlets/purl/7061675Test

المؤلفون: Perov, Polievkt

المصدر: College of Arts & Sciences Faculty Works

مصطلحات موضوعية: neutrino, neutrino pairs, gravitation, galaxies, expansion of Universe, Astrophysics and Astronomy, Cosmology, Relativity, and Gravity, Elementary Particles and Fields and String Theory, Physical Processes

الوصف: The axial electric potentials of neutrinos as neutral composite structures, while being very small at large distances, do not vanish, and the same can be said about the neutrino “asymmetric dipoles†(paired neutrinos of not the same kind). Depending on the orientation of the “asymmetric dipoleâ€, its far-field electric potential in some direction can be positive or negative, interacting with other “dipoles†at that large distance attractively or repulsively depending on their mutual orientation. The mutual orientation of the dipoles locally (inside a galaxy) might be such that they are aligned and experience the attractive force toward the local center of the system of “dipolesâ€, and this can be the source of attractive interaction called gravitation. The dipoles near some other local center (in some other galaxy) will be aligned in such a way that they are attracted to that local center (a galaxy) and repelled from other local centers (other galaxies). That can cause the Universe to expand. The Universe can be considered as having a domain structure where the neutral “asymmetric dipoles†are oriented toward the centers of the local domains (resulting in the attraction) while that “local alignments†in different galaxies causes a repulsion between the domains (galaxies). We think that such EM mechanism of attraction and repulsion of neutral matter can for the first logically explain the coexistence of the attractive local gravitation inside the galaxies and the repulsive interaction between the remote galaxies leading to the expansion of the Universe.

وصف الملف: application/pdf

العلاقة: https://dc.suffolk.edu/cas-faculty/23Test; https://dc.suffolk.edu/context/cas-faculty/article/1024/viewcontent/Perov_Neutrinos__Gravitation__Domain_Structure_and_Expansion_of_the_Universe_031824.pdfTest

الإتاحة: https://dc.suffolk.edu/cas-faculty/23Test
https://dc.suffolk.edu/context/cas-faculty/article/1024/viewcontent/Perov_Neutrinos__Gravitation__Domain_Structure_and_Expansion_of_the_Universe_031824.pdfTest

المؤلفون: Osterman, David Z

المصدر: Doctoral Dissertations

مصطلحات موضوعية: low-mass sub-Gev dark matter detection - HeRALD, superconducting aluminum quasiparticles, superfluid helium, laser-scanning microscopy, low-energy excess (LEE), transition edge sensor (TES), Condensed Matter Physics, Elementary Particles and Fields and String Theory, Instrumentation

الوصف: Dark matter, one of the greatest mysteries in physics, continues to elude direct detection even after decades of effort. Physicists, in more recent years, are looking toward smaller mass ranges (sub-GeV), and a slew of new detector ideas have emerged. The HeRALD experiment seeks to use superfluid helium as a target to detect low-mass dark matter through the production of phonons and helium excimers as well as the resulting photons and quantum-evaporated helium atoms. HeRALD and many other experiments across particle physics use transition edge sensors (TESs) to detect small energy deposits - for HeRALD, such events are characteristic of a collision between a low-mass dark matter particle and a target He atom. Energy from impinging photons and He atoms are funneled to the TES through athermal phonons in a silicon substrate followed by quasiparticles (broken Cooper pairs) in thin-film superconducting aluminum fins. For all such calorimeters, energy efficiency is reduced by quasiparticles (QPs) becoming trapped by impurities in the Al. Additionally, immersed sensors could potentially lose QP energy to the surrounding superfluid He. In this thesis, I present studies of quasiparticle diffusion in superconducting Al fins using a laser-scanning microscopy-based technique. The characteristic QP trapping length (or diffusion length) is measured with the TES-fin device both in vacuum and immersed in superfluid He, to measure the QP energy lost to the superfluid. QP are produced at a localized origin in the Al film using a focused 1550nm laser coupled to a single-mode optical fiber mounted on piezoelectric nanopositioners. The resulting QP propagation is then monitored using a TES, and described using a simple 1D diffusion model. The measurements of 100µm-scale quasiparticle diffusion determine that the Al fins - fabricated at Argonne National Laboratory - work sufficiently well to be used in TES-based detectors. Additionally, no significant drop in QP collection efficiency due to device immersion in superfluid helium was ...

وصف الملف: application/pdf

العلاقة: https://scholarworks.umass.edu/dissertations_2/3076Test; https://scholarworks.umass.edu/context/dissertations_2/article/4161/viewcontent/Osterman.pdfTest

الإتاحة: https://doi.org/10.7275/36464222Test
https://scholarworks.umass.edu/dissertations_2/3076Test
https://scholarworks.umass.edu/context/dissertations_2/article/4161/viewcontent/Osterman.pdfTest