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Bioprobe based on fluorescence is widely used in biological and medical research due to its high sensitivity and selectivity. Yet, its quantification in vivo is complicated and often compromised by the interaction between the fluorophore with the environmental factors, as well as the optical scattering and absorption by the tissue. A high florescence quantum yield and minimal interference by the environment are key requirements for designing an effective bioprobe, and the pre-requisitions severely limit the available options. We propose that a comprehensive evaluation of potential bioprobe can be achieved by simultaneously measuring both radiative and non-radiative transitions, the two fundamental and complementary pathways for the energy de-excitation. This approach will not only improve the accuracy of the quantification by catching the information from a broader spectrum of the energy, but also provide additional information of the probe environment that often impacts the balance between the two forms of the energy transition. This work first analyzes the underlying mechanism of the hypothesis. The practical feasibility is then tested by means of simultaneous measurements of photoacoustic signal for the non-radiative and fluorescence for the radiative energy processes, respectively. It is demonstrated that the systematic evaluation of the probe energy de-excitation results in an improved quantitative tracing of a bioprobe in complex environment. [ABSTRACT FROM AUTHOR]

The Rayleigh–Ritz variational method with multiconfiguration interaction wave functions is used to calculate energies, radiative transitions and radial expectation values of the 1 s 2 2 s 2 2 p 2 3 P ground state and the 1 s 2 2 s 2 p 3 5 S , 1 D , 3 S highly excited states of C and O 2 + . Hyperfine structure parameters and magnetic coupling constants of these states are also calculated in this work. The present calculations agree well with theoretical and experimental values available in the literature. Other data not reported in the literature are expected to offer valuable benchmarks for future research. [ABSTRACT FROM AUTHOR]

We present an exploratory study on the radiative transition for the charm-strange meson: using twisted mass lattice quantum chromodynamics gauge configurations. The form factor for meson is also determined. The simulation is performed on lattices with lattice spacings fm and lattice size , and fm and lattice size , respectively. Our numerical results for radiative decay width and the experimental data overlap within the margin of error. [ABSTRACT FROM AUTHOR]

In this paper, we perform an systematic study of the radiative transitions among the bottomonium states using the heavy quarkonium effective Lagrangians, and make predictions for the ratios among the radiative decay widths of a special multiplet to another multiplet. The predictions can be confronted with the experimental data in the future. [ABSTRACT FROM AUTHOR]

The heavy diquark symmetry (HDS) of doubly heavy baryons (DHBs) provides new insights into the spectroscopy of these hadrons. We derive the consequences of this symmetry for the mass spectra and the decay widths of DHBs. We compare these symmetry constraints to results from a nonrelativistic quark model for the mass spectra and results from the 3P0 model for strong decays. The quark model we implement was not constructed with these symmetries and contains interactions which explicitly break HDS. Nevertheless these symmetries emerge. We argue that the 3P0 model and any other model for strong transitions which employs a spectator assumption explicitly respects HDS. We also explore the possibility of treating the strange quark as a heavy quark and apply these ideas to Ξ, Ξc and Ξb baryons. [ABSTRACT FROM AUTHOR]

We study the contribution of the antisymmetric tensor unparticle mediation to the branching ratios of the radiative lepton flavor violating decays and predict a restriction region for free parameters of the scenario by using experimental upper limits. We observe that the branching ratios of the radiative lepton flavor violating decays are sensitive to the fundamental mass scales of the scenario and to the scale dimension of antisymmetric tensor unparticle. We obtain a more restricted set for the free parameters in the case of the μ→e γ decay. [ABSTRACT FROM AUTHOR]

Forward transition radiation is considered in an ultrasonic superlattice excited in a finite thickness plate under oblique incidence of relativistic electrons. We investigate the influence of acoustic waves on both the intensity and polarization of the radiation. In the quasi-classical approximation, formulas are derived for the vector potential of the electromagnetic field and for the spectral-angular distribution of the radiation intensity. It is shown that the acoustic waves generate new resonance peaks in the spectral and angular distributions. The heights and the location of the peaks can be controlled by choosing the parameters of the acoustic wave. The numerical examples are given for a plate of fused quartz. [ABSTRACT FROM AUTHOR]

The expressions for super-allowed beta-decay transition rates have been derived within the context of the Coriolis coupling model. The derived expressions, valid for the beta-decay between any two mirror nuclei, have been applied to calculate super-allowed beta-decay transition rates of 21Na, 23Mg, 25Al, and 27Si. Without the use of any hindrance factor, the calculated rates agree well with the data and also with the calculations done using the shell model with configuration admixture. [ABSTRACT FROM AUTHOR]

We propose a general technique to solve the classical many-body problem with radiative damping. We modify the short-distance structure of Maxwell electrodynamics. This allows us to avoid runaway solutions as if we had a covariant model of extended particles. The resulting equations of motion are functional differential equations (FDEs) rather than ordinary differential equations (ODEs). Using recently developed numerical techniques for stiff, retarded FDEs, we solve these equations for the one-body central force problem with radiative damping. Our results indicate that locally the magnitude of radiation damping may be well approximated by the standard third-order expression but the global properties of our solutions are dramatically different. We comment on the two-body problem and applications to quantum field theory and quantum mechanics. [ABSTRACT FROM AUTHOR]

Qualitative analysis of additional energy of neutrino and antineutrino in plasma is performed. A general expression for the neutrino self-energy operator is obtained in the case of ultra-high energies when the local limit of the weak interaction is not valid. The neutrino and antineutrino additional energy in plasma is calculated using the dependence of the W- and Z-boson propagators on the momentum transferred. The kinematical region for the neutrino radiative transition (the so-called "neutrino spin light") is established for some important astrophysical cases. For high energy neutrino and antineutrino, dominating transition channels in plasma, νe + e+ → W+, $\bar\nu_e + e^- \to W^-$ and $\bar\nu_{\ell} + \nu_{\ell} \to Z$, are indicated. [ABSTRACT FROM AUTHOR]

It is argued that the observed enhancement of the hadronic transition ϒ(4S) → ϒ(1S)η relative to ϒ(4S) → ϒ(1S)ππ can be explained if the resonance ϒ(4S) contains an admixture of a four-quark component, possibly due to the coupling to the meson channel $B\bar B$. A test of the discussed mechanism by searching for the transition ϒ(4S) → ϒ(1S)η′(958) is suggested. Some properties of possible four-quark states related to the suggested one by the heavy quark spin symmetry are also discussed. [ABSTRACT FROM AUTHOR]

Experimental tests of the Λ(1405) properties are suggested. These could reflect the position and shape of this state in the $\overline K N$ channel. The first test consists in precise determinations of the level widths in the highest accessible K-mesic atom states. One needs to study the dependence of these widths on the binding energy of the valence protons in the involved nuclei. The second test consists in the measurement of radiative transitions from the P-wave atomic hydrogen levels to the Λ(1405) state. In both cases one can study the absorptive part of $\overline K N$ scattering amplitude in the subthreshold region. [ABSTRACT FROM AUTHOR]

In order to understand the structure of the X(3872), we have studied the effects of the $c\bar{c}$ core state coupling to the multi-hadronic states such as $D^0\,\overline{D^{0*}}$, ρ J/ψ etc. We have calculated the transition strength S(E) using the Green's function approach with the simple solvable interactions. We have also studied the S(E) in the case of no $c\bar{c}$ core state, namely, the $D^0\,\overline{D^{0*}}$ molecule. Since the calculated shapes of the transition strengths are different from each other, we shall be able to determine the degree of the mixing of the $c\bar{c}$ state in the X(3872) from the shape of the energy spectrum. [ABSTRACT FROM AUTHOR]

B meson radiative effective neutral current ("penguin") decays rates, including the b → sγ and b → dγ transitions, represent one of the most powerful indirect constraints on new physics scenarios. Approaches to the measurements of the b → sγ width are presented, and the combined result is compared to its Standard-Model expectation. Various approaches to studying the b → dγ transition involve a comparison to corresponding b → sγ processes, and are presented in terms of the extracted ratio of CKM coupling parameters |Vtd/Vts|, which is precisely constrained within the context of the Standard Model by measurements of B meson mixing. The relative accuracy of experimental constraints on radiative penguin transition rates are better than ±7% for b → sγ and ±20% for b → dγ/b → sγ. The implications of the increasingly precise complementary constraint on |Vtd/Vts| that arises from the measurement radiative penguin decay widths may not yet be fully appreciated. There is significant potential for the improvement of these constraints in both the near (particularly for b → sγ) and longer terms. [ABSTRACT FROM AUTHOR]

The mesoscopic dynamic simulation (MesoDyn) has been carried out to investigate the phase structure and the aggregate properties of triblock copolymers (ethylene oxide)37 (propylene oxide)56 (ethylene oxide)37 (P105) in aqueous solution. A Gaussian chain model is successfully built according to the equivalent chain method and the Flory-Huggins interaction parameters, χ, used for determining the repulsions between different chain segments are computed. Simulation results show that P105 can form several microstructures including spherical micelles, ellipsoid micellar cluster, worm-like micelles, defective bicontinuous phase, and bicontinuous phase with increasing concentration. A special transition phase structure of P105 is found in the spherical micellar region. The dynamic evolution processes of spherical micelles are investigated by observing the induction time before phase separation and the changing of isosurface during phase separation. The influence of P105 concentration on the density of micelles at equilibrium state is also discussed, which shows that the increase of P105 concentration will lead to the decrease of micelles' amount. Two kinds of growth mechanisms during phase separation are discussed by MesoDyn simulation. [ABSTRACT FROM AUTHOR]

The radiative leptonic decays Ds → μνμγ and D → μνμγ are investigated at the tree level within the relativistic independent quark model based on the confining potential in the scalar–vector harmonic form. The branching ratios for these decays in the vanishing lepton mass limit are obtained as ℬr(Ds → μνμγ) = 4.94×10-4 and ℬr(D → μνμγ) = 3.34×10-5, which includes the contributions of the internal bremsstrahlung and structure dependent diagrams at the level of the quark constituents. Finally, the photon energy spectra as predicted here is found to be symmetric about the peak value of the photon energy at $E_\gamma = \frac{M_{D_{(s)}}}{4}$. [ABSTRACT FROM AUTHOR]

We reported the observation of Y(2175) in ɸf0(980) mass spectrum in J/ψ → ηɸf0(980) with f0(980) → π+π-, the partial wave analysis results of J/ψ → γɸɸ, the measurement of $J/\psi \to \omega K\bar K\pi$, $\phi K\bar K\pi$, and the observation of $K^- \bar \Lambda$ threshold enhancement in $J/\psi \to pK^- \bar\Lambda$, based on 5.8 × 107 J/ψ events collected at BESII. We reported the measurement of ψ(2S) radiative decays with 1.4 × 107 ψ(2S) events and the measurement of D decay branching fractions with 33 pb-1 data collected at and around 3.773 GeV as well. The status of BESIII/BEPCII project is also presented. [ABSTRACT FROM AUTHOR]

The chiral structure of heavy-light mesons is explored with a particular focus on the nature of the DsJ charmed mesons. Theoretical predictions for the hadronic and radiative decays of these mesons are compared to recent experimental data. [ABSTRACT FROM AUTHOR]

We present in this talk recent results of the vector and axial-vector transitions of the nucleon to the pentaquark baryon Θ+, based on the SU(3) chiral quark-soliton model. The results are summarized as follows: K*NΘ vector and tensor coupling constants turn out to be gK*NΘ ≃ 0.81 and fK*NΘ ≃ 0.84, respectively, and the KNΘ axial-vector coupling constant to be $g^{\ast}_{A} \simeq 0.05$. As a result, the total decay width for Θ+ → NK becomes very small: ΓΘ→NK ≃ 0.71 MeV, which is consistent with the DIANA result ΓΘ→NK = 0.36 ± 0.11 MeV. [ABSTRACT FROM AUTHOR]

In a shell-model calculation with traditional effective charges, theoretical B(E2) values are larger than experimental values for neutron-rich carbon isotopes 16C and 18C. Using the shell-model with 2ħw excitations in the first order perturbation theory, we investigate the B(E2) values and the effective charges for stable and neutron-rich carbon isotopes. [ABSTRACT FROM AUTHOR]

The cosmological QCD transition is studied using lattice simulations. The order of the transition is determined via a finite volume analysis. It is found to be an analytic crossover. The transition temperature is determined in physical units using three different definitions. All results are obtained using four different lattice spacings (a ≈ 0.3, 0.2, 0.15 and 0.12 fm) and a continuum extrapolation. [ABSTRACT FROM AUTHOR]

The spin-orbit splittings of 13C and 13N corresponding to the ground state and second 0+ state (Hoyle state) in 12C are investigated within a 12C+N model. The agreement of the calculated results with experiments suggests that the $1/2_2^-$ and $3/2_2^-$ states around Ex = 9 ~ 10 MeV in 13C and 13N can be interpreted as the spin-orbit partner with the $^{12}{\rm C}(0_2^+)+N$ configuration. We also discuss the positive parity states (including $1/2^+_2$) of 13C and 13N around the $^{12}{\rm C}(0_2^+)+N$ threshold, indicating to have the configuration of the Hoyle state in 12C plus a valence nucleon in sd shell. [ABSTRACT FROM AUTHOR]

Cross sections for 13C(α,α′) reactions at Eα = 400 MeV have been measured to obtain the monopole and quadrupole transition strengths. The excitation strengths are compared with the shell-model predictions. It is suggested that the large monopole strengths observed for the $1/2^-_2$ and $1/2^-_3$ states in 13C are attributed to the cluster structure of those states. [ABSTRACT FROM AUTHOR]

The status of exclusive two-body and three-body baryonic B decays is reviewed. The threshold enhancement effect in the dibaryon invariant mass and the angular distributions in the dibaryon rest frame are stressed and explained. Weak radiative baryonic B decays mediated by the electromagnetic penguin process b→sγ are discussed. Puzzles with the correlation observed in $B^-\to p\bar p K^-$ decay and the unexpectedly large rate observed for $B\to\Lambda_c\bar\Lambda_cK$ are examined. The former may indicate that the $p\bar p$ system is produced through some intermediate states, while the latter implies the failure of naive factorization for $\Lambda\bar\Lambda K$ modes and may hint at the importance of final-state rescattering effects. [ABSTRACT FROM AUTHOR]

Measurements of the angles and sides of the unitarity triangle and of the rates of rare B meson decays are crucial for the precise determination of Standard Model parameters and are sensitive to the presence of new physics particles in the loop diagrams. In this paper the recent measurements performed in this area by BABAR and Belle will be presented. The direct measurement of the angle α is for the first time as precise as the indirect determination. The precision of the |Vub| determination has improved significantly with respect to previous measurement. New limits on B → τν decays are presented, as well as updated measurements on b → s radiative transitions and a new observation of b → dγ transition made by Belle. [ABSTRACT FROM AUTHOR]

It is pointed out that in the decays $X(3872) \to D{\bar D}\gamma$ the possible "molecular" component of the X(3872) should give rise essentially only to a $D^0{\bar D}^0\gamma$ final state with a predictable spectrum, and should yield virtually no contribution to decays into D+D-γ. The latter final state with charged D mesons should however arise from the radiative decays of the short-distance core of the X(3872) through the transition X(3872) → ψ(3770)γ. Thus an observation of the radiative decays of X(3872) to pairs of neutral and charged D mesons would provide an insight into the internal dynamics of the X(3872) resonance. [ABSTRACT FROM AUTHOR]

The flavor-changing neutral current transition b → s can serve as a sensitive probe of WIMP dark matter models, if the WIMP mass is under 2 GeV. In this work we extend our earlier analysis to a generic class of models where the interaction between the dark matter sector and the Standard Model matter sector is mediated by the Higgs boson(s). We show that experimental limits on the decays of B-mesons to K(K*) and missing energy provide stringent constraints on the parameter space of such models, but do not rule out sub-GeV WIMPs in a model-independent way. We find that in the context of the NMSSM with light pseudoscalar Higgs, the WIMP masses under a few hundred MeV are generically excluded with the exception of few highly tuned points in the parameter space. [ABSTRACT FROM AUTHOR]

Weak radiative decays of charmed baryons into strange baryons induced by the electromagnetic Penguin, are estimated by using quark model approach. Heavy quark effective theory and poles are used to derive the branching ratios of [formula] and our calculated result is [formula]. The electromagnetic penguin contribution to Ω[sub b] → Ωγ is estimated by two methods and its calculated branching ratio is of the order ~ 10[sup -5]. Hence we conclude that weak radiative decays of bottom hadrons are dominated by the short-distance b → sγ mechanism. [ABSTRACT FROM AUTHOR]

The recently observed by CLEO cascade decays γ(3S) → γχ′[SUBbJ] → γωγ are discussed. It is shown that within the nonrelativistic description of bottomonium in the heavy b quark limit, the ratio of the rates of the transitions χ′[SUBbJ] → ωγ with J = 1 and J = 2 should be given by the ratio of the corresponding S wave phase space factors. As a result, the rate of the observed cascade transitions through the χ′[SUBb2] resonance should be close to that through the ξ′[SUBb1]. It is suggested that the ratio of the discussed cascade rates can also be tested by measuring a simple angular correlation. [ABSTRACT FROM AUTHOR]

Electromagnetic radiative penguin decays of the B meson were studied with the BABAR detector at SLAC's PEP-II asymmetric-energy B Factory. Branching fractions and isospin asymmetry of the decay B → K*γ, branching fractions of $B \to K^*_2(1430)\gamma$, and a search for B0 → ϕγ are presented. The decay rates may be enhanced by contributions from non-standard model processes. [ABSTRACT FROM AUTHOR]