The combination of reversible angular dispersion-induced microbunching (ADM) and the rapid damping storage ring provides a storage-ring-based light source with the capability to produce longitudinal coherent radiation with a high repetition rate. This paper presents a prototype design for a test facility based on the study by Jiang et al. [Sci. Rep. (2022), 12, 3325]. The modulation–demodulation section is inserted into a long straight section of the storage ring instead of a bypass line, which poses great challenges for the optimization of the nonlinear dynamics of the storage ring. However, this design avoids the challenging injection and extraction system connecting to the bypass line. To utilize mature laser technology and reduce the difficulty of the reversible ADM lattice design, we use a long-wavelength 1030 nm seed laser. In the simulation, we achieved 20th harmonic radiation with a bunching factor of about 7.2%. The growth rate of vertical emittance and energy spread of the electron beam for a single pass are about 11% and 0.02%, respectively. When the energy of the electron beam is 800 MeV and two sets of damping wigglers are employed, the damping time in the vertical plane is reduced to 8.31 ms. This results in a 438 kHz repetition rate of the coherent radiation at the new equilibrium state.
Nuclear and particle physics. Atomic energy. Radioactivity, Crystallography
The spectra measured with cadmium telluride (CdTe) detectors show high spectral distortions that must be corrected by applying a mathematical algorithm along with the detector's response functions. Simplified computational modeling of the CdTe detector is generally used to obtain its response functions. In this work, the Monte Carlo code MCNPX was used to study the response functions of a CdTe detector using more complex detector modeling and compared it with those obtained by simplified modeling. Raw spectra were corrected using the response matrices obtained for the simplified and detailed modeling of the CdTe and compared with those obtained with reference-validated software.
Medical physics. Medical radiology. Nuclear medicine, Radioactivity and radioactive substances
R. Aaij, A. S. W. Abdelmotteleb, C. Abellan Beteta
et al.
Abstract A measurement of $${{D}} ^0$$ D 0 meson production by the LHCb experiment in its fixed-target configuration is presented. The production of $${{D}} ^0$$ D 0 mesons is studied with a beam of 2.5 $$\,\text {Te\hspace{-1.00006pt}V}$$ Te V protons colliding on a gaseous neon target at rest, corresponding to a nucleon–nucleon centre-of-mass energy of $$\sqrt{s_{\scriptscriptstyle \text {NN}}} = 68.5\,\,\text {Ge\hspace{-1.00006pt}V} $$ s NN = 68.5 Ge V . The sum of the $${{D}} ^0$$ D 0 and $${\hspace{0.0pt}\overline{\hspace{0.0pt}{D}}} {}^0$$ D ¯ 0 production cross-section in $$p\text {Ne}$$ p Ne collisions in the centre-of-mass rapidity range $$y^{\star }\in [-2.29, 0]$$ y ⋆ ∈ [ - 2.29 , 0 ] is found to be $$\sigma _{D^{0}}^{y^\star \in [-2.29, 0]} = 48.2 \pm 0.3 \pm 4.5 \,\upmu \text {b}/\text {nucleon}$$ σ D 0 y ⋆ ∈ [ - 2.29 , 0 ] = 48.2 ± 0.3 ± 4.5 μ b / nucleon where the first uncertainty is statistical and the second is systematic. The $${{{D}} ^0}-{{\hspace{0.0pt}\overline{\hspace{0.0pt}{D}}} {}^0} $$ D 0 - D ¯ 0 production asymmetry is also evaluated and suggests a trend towards negative values at large negative $$y^{\star }$$ y ⋆ . The considered models do not account precisely for all the features observed in the LHCb data, but theoretical predictions including 1 $$\%$$ % intrinsic charm and 10 $$\%$$ % recombination contributions better describe the data than the other models considered.
Astrophysics, Nuclear and particle physics. Atomic energy. Radioactivity
Abstract Anti-D3 branes at the bottom of warped throats, commonly used to uplift the cosmological constant in String-Theory de Sitter proposals, source a plethora of supersymmetry-breaking fluxes, that can interact nontrivially with other ingredients of the flux compactification. In this paper we perform a complex-structure decomposition of these fluxes, and compute the effect of the (0,3) flux component on the stabilization of Kähler moduli via D7-branes gaugino condensation. This allows us to obtain a new constraint on the validity of this stabilization mechanism. This effect does not appear hard to satisfy in de Sitter construction proposals that use long warped throats, but may be problematic in proposals where the warping is small.
Nuclear and particle physics. Atomic energy. Radioactivity
Abstract In [1], we performed the first complete computation of the back-to-back inclusive dijet cross-section in Deeply Inelastic Scattering (DIS) at small x Bj to next-to-leading order (NLO) in the Color Glass Condensate effective field theory (CGC EFT). We demonstrate here that for dijets with relative transverse momentum P ⊥ and transverse momentum imbalance q ⊥, to leading power in q ⊥/P ⊥, the cross-section for longitudinally polarized photons can be fully factorized into the product of a perturbative impact factor and the non-perturbative Weizsäcker-Williams (WW) transverse momentum dependent (TMD) gluon distribution to NLO accuracy. The impact factor can further be expressed as the product of a universal soft factor which resums Sudakov double and single logs in P ⊥/q ⊥ and a coefficient function given by a remarkably compact analytic expression. We show that in the CGC EFT the WW TMD satisfies a kinematically constrained JIMWLK renormalization group evolution in rapidity. This factorization formula is valid to all orders in Q s /q ⊥ for q ⊥, Q s ≪ P ⊥, where Q s is the semi-hard saturation scale that grows with rapidity.
Nuclear and particle physics. Atomic energy. Radioactivity
Abstract A wide range of dark matter candidates have been proposed and are actively being searched for in a large number of experiments, both at high (TeV) and low (sub meV) energies. One dark matter candidate, a deeply bound uuddss sexaquark, $$S$$ S , with mass $$\sim 2$$ ∼ 2 GeV (having the same quark content as the hypothesized H-dibaryon, but long lived) is particularly difficult to explore experimentally. In this paper, we propose a scheme in which such a state could be produced at rest through the formation of $$\bar{p}$$ p ¯ – $$^3$$ 3 He antiprotonic atoms and their annihilation into $$S$$ S + $$K^+K^+\pi ^-$$ K + K + π - , identified both through the unique tag of a $$S=+2, Q=+1$$ S = + 2 , Q = + 1 final state, as well as through full kinematic reconstruction of the final state recoiling against it.
Astrophysics, Nuclear and particle physics. Atomic energy. Radioactivity
Simone D’Onofrio, Federica Fragomeno, Claudio Gambino
et al.
Abstract The metric and the electromagnetic potential generated by a static, spherically symmetric charged massive object in any dimension are given by the Reissner-Nordström-Tangherlini solution. We derive the expansion of this solution up to third post-Minkowskian order by computing the classical contribution of scattering amplitudes describing the emission of either a graviton or a photon from a massive charged scalar field up to two loops. In four and five dimensions these amplitudes develop ultraviolet divergences that are cancelled by higher-derivative counterterms in a way that generalises what was recently shown to happen in the chargeless case. This renormalisation procedure produces logarithmic terms that match exactly those produced in the post-Minkowskian expansion of the classical solution in de Donder gauge.
Nuclear and particle physics. Atomic energy. Radioactivity
Abstract It has been conjectured that duality cascade occurs in the N $$ \mathcal{N} $$ = 3 supersymmetric Yang-Mills Chern-Simons theory with the gauge group U(N) k × U(N + M) −k coupled to two bi-fundamental hypermultiplets. The brane picture suggests that this duality cascade can be generalized to a class of 3d N $$ \mathcal{N} $$ = 3 supersymmetric quiver gauge theories coming from so-called Hanany-Witten type brane configurations. In this paper we perform non-perturbative tests of the duality cascades using supersymmetry localization. We focus on S 3 partition functions and prove predictions from the duality cascades. We also discuss that our result can be applied to generate new dualities for more general theories which include less supersymmetric theories and theories without brane constructions.
Nuclear and particle physics. Atomic energy. Radioactivity
The history of sciences is rich in founding experiments, which have given rise to such developments that they constituted full-fledged disciplines. Much more rarely, knowledge coming from very distant horizons converged at a moment to offer a very new vision of old results and to provoke an explosion of new research. This was the case for the solvated electron. But where does such a concept come from, of an electron isolated in a liquid whose molecules are polarized by its charge?
Nuclear and particle physics. Atomic energy. Radioactivity, Medical physics. Medical radiology. Nuclear medicine
Abstract Bosonic string moving in coordinate dependent background fields is considered. We calculate the generalized currents Poisson bracket algebra and find that it gives rise to the Courant bracket, twisted by a 2-form $$2B_{\mu \nu }$$ 2Bμν . Furthermore, we consider the T-dual generalized currents and obtain their Poisson bracket algebra. It gives rise to the Roytenberg bracket, equivalent to the Courant bracket twisted by a bi-vector $$\Pi ^{\mu \nu }$$ Πμν , in case of $$\Pi ^{\mu \nu } = 2 {^\star B}^{\mu \nu } = \kappa \theta ^{\mu \nu }$$ Πμν=2⋆Bμν=κθμν . We conclude that the twisted Courant and Roytenberg brackets are T-dual, when the quantities used for their deformations are mutually T-dual.
Astrophysics, Nuclear and particle physics. Atomic energy. Radioactivity
Abstract Beginning with results for the leading-twist two-particle distribution amplitudes of $$\pi $$ π - and K-mesons, each of which exhibits dilation driven by the mechanism responsible for the emergence of hadronic mass, we develop parameter-free predictions for the pointwise behaviour of all $$\pi $$ π and K distribution functions (DFs), including glue and sea. The large-x behaviour of each DF meets expectations based on quantum chromodynamics; the valence-quark distributions match extractions from available data, including the pion case when threshold resummation effects are included; and at $$\zeta _5=5.2\,$$ ζ 5 = 5.2 GeV, the scale of existing measurements, the light-front momentum of these hadrons is shared as follows: $$\langle x_{\mathrm{valence}} \rangle ^\pi = 0.41(4)$$ ⟨ x valence ⟩ π = 0.41 ( 4 ) , $$\langle x_{\mathrm{glue}} \rangle ^\pi = 0.45(2)$$ ⟨ x glue ⟩ π = 0.45 ( 2 ) , $$\langle x_{\mathrm{sea}} \rangle ^\pi = 0.14(2)$$ ⟨ x sea ⟩ π = 0.14 ( 2 ) ; and $$\langle x_{\mathrm{valence}} \rangle ^K = 0.42(3)$$ ⟨ x valence ⟩ K = 0.42 ( 3 ) , $$\langle x_{\mathrm{glue}} \rangle ^K = 0.44(2)$$ ⟨ x glue ⟩ K = 0.44 ( 2 ) , $$\langle x_{\mathrm{sea}} \rangle ^K = 0.14(2)$$ ⟨ x sea ⟩ K = 0.14 ( 2 ) . The kaon’s glue and sea distributions are similar to those in the pion, although the inclusion of mass-dependent splitting functions introduces some differences on the valence-quark domain. This study should stimulate improved analyses of existing data and motivate new experiments sensitive to all $$\pi $$ π and K DFs. With little known empirically about the structure of the Standard Model’s (pseudo-) Nambu-Goldstone modes and analyses of existing, limited data being controversial, it is likely that new generation experiments at upgraded and anticipated facilities will provide the information needed to resolve the puzzles and complete the picture of these complex bound states.
Astrophysics, Nuclear and particle physics. Atomic energy. Radioactivity