This paper presents the design and optimization of a lutetium yttrium oxyorthosilicate(LYSO)crystal electromagnetic calorimeter(ECAL)for the DarkSHINE experiment,which aims to identify dark photons as potential mediat...This paper presents the design and optimization of a lutetium yttrium oxyorthosilicate(LYSO)crystal electromagnetic calorimeter(ECAL)for the DarkSHINE experiment,which aims to identify dark photons as potential mediators of dark forces.The ECAL design was evaluated through comprehensive simulations,focusing on optimizing dimensions,material selection,energy distribution,and energy resolution.The configuration consisted of 21×21×11 LYSO crystals,each measuring 2.5 cm×2.5 cm×4 cm,arranged in a staggered layout to enhance signal detection efficiency.A 4 GeV energy dynamic range was established to ensure accurate energy measurements without saturation,which is essential for background rejection and signal identification.A detailed digitization model was developed to simulate scintillation,silicon photomultiplier,and analog-to-digital converter behaviors,providing a realistic representation of the detector's performance.Additionally,the study assessed radiation damage in the ECAL region,emphasizing the importance of using radiation-resistant scintillators and silicon sensors.展开更多
The massless dark photon~γ can only interact with the Standard Model(SM)sector via higherdimensional operators.In this letter,we investigate its production associated with the ordinary photonγfrom the lepton flavor ...The massless dark photon~γ can only interact with the Standard Model(SM)sector via higherdimensional operators.In this letter,we investigate its production associated with the ordinary photonγfrom the lepton flavor violation(LFV)process l_(i)→l_(j)γγ and di-production from the LFV process l_(i)→l_(j)γγ induced by dipole operators.Comparing the obtained numerical results with the corresponding experimental measurements,we obtain the constraints on the effective couplings of γ with the SM charged leptons.The upper limit of the effective coupling|DLμe|2+|DRμe|2coming from the process μ→e~γγis looser than the processμ→eγ by about one order of magnitude.展开更多
Dark photons,as a minimal extension of the Standard Model through an additional Abelian gauge group,may propagate relativistically across the galaxy,originating from dark matter decay or annihilation,thereby contribut...Dark photons,as a minimal extension of the Standard Model through an additional Abelian gauge group,may propagate relativistically across the galaxy,originating from dark matter decay or annihilation,thereby contributing to a galactic dark photon background.The generation of dark photons typically favors certain polarization modes,which are dependent on the interactions between dark matter and dark photons.We introduce a framework in which a resonant cavity is utilized to detect and differentiate these polarizations,leveraging the daily variation in expected signals due to the anisotropic distribution of dark photons and the rotation of the Earth.We conduct an experimental search using superconducting radio-frequency cavities,noted for their exceptionally high quality factors,proving them to be effective telescopes for observing galactic dark photons.This approach establishes the most stringent limits yet on the kinetic mixing coefficient between dark photons and electromagnetic photons,thereby unveiling a novel avenue for the indirect search for dark matter via multi-messenger astronomy.展开更多
The ultralight dark photon is an intriguing dark matter candidate.The interaction between visible and dark photons is introduced by the gauge kinetic mixing between the field strength tensors of the Abelian gauge grou...The ultralight dark photon is an intriguing dark matter candidate.The interaction between visible and dark photons is introduced by the gauge kinetic mixing between the field strength tensors of the Abelian gauge groups in the Standard Model and dark sector.Relativistic electrodynamics was generalized to quantum electromagnetodynamics(QEMD)in the presence of both electric and magnetic charges.The photon is described by two fourpotentials corresponding to two U(1)gauge groups and satisfying non-trivial commutation relations.In this work,we construct low-energy dark photon-photon interactions in the QEMD framework and obtain new dark photonphoton kinetic mixings.Then,we derive the consequent field and Maxwell's equations.We also investigate the detection strategies of dark photons as light dark matter and generic kinetic mixings at haloscope experiments.展开更多
We discuss almost degenerate vector dark matter and dark photonsinduced from the hidden SU(2)Hgauge sector,where it is spontaneously broken by the vacuum expectation value of SU(2)Hdoublet.Kinetic mixing between SU(2)...We discuss almost degenerate vector dark matter and dark photonsinduced from the hidden SU(2)Hgauge sector,where it is spontaneously broken by the vacuum expectation value of SU(2)Hdoublet.Kinetic mixing between SU(2)Hand U(1)Ygauge fields can be generated by introducing a dimension six operator realizing dark photon interactions.In estimating relic density,we focus on the process in which dark matter annihilates into dark photons and search for the region of dark matter mass and gauge coupling realizing observed relic density.We then discuss constraints from dark photon physics,thermalization of dark sector,and direct detection of dark matter.It is then found that constraints from direct detection experiments give us the strongest upper limits on the dark photon interactions.展开更多
Purpose In order to precisely control the resonant frequency of RF superconducting cavity to detect dark photon dark matter,and to be able to tune within a certain frequency range,it is necessary to design a low-tempe...Purpose In order to precisely control the resonant frequency of RF superconducting cavity to detect dark photon dark matter,and to be able to tune within a certain frequency range,it is necessary to design a low-temperature tuner for frequency control on the bare cavity.Methods Two type mechanical tuners have been designed for the 1.3 GHz single-cell bare cavity and 650 MHz single cell bare cavity.The tuner device tunes the frequency of RF superconducting cavity for the detection of dark photons and dark matter and measures its tuning range and accuracy in both room-temperature and low-temperature environments.Results The tuner for the 1.3 GHz cavity has a tuning accuracy of 1 Hz per step and a tuning range of 1.37 MHz at low temperature.The tuner for the 650 MHz cavity has a tuning range of 467 kHz at low temperatures,with a tuning accuracy of 1.77 Hz per step.Conclusion The designed tuner can meet the requirements of RF superconducting cavity tuning for detecting dark photons and dark matter,and its adjustable range,precision and stability ensure that the detection experiment can be carried out smoothly.展开更多
In this paper, we derive the bright and dark photon number states for spatial interference of two or more light beams and succeed in the explanation of Young's interference experiment, and also achieve a better co...In this paper, we derive the bright and dark photon number states for spatial interference of two or more light beams and succeed in the explanation of Young's interference experiment, and also achieve a better comprehension of the well known comment of Dirac 'each photon only interferences with itself'. Prom the fully quantum point of view, the origin of the interference fringes consists in the mode transformation and the detection of double-slit states.展开更多
Dark sector may couple to the Standard Model via one or more mediator particles.We discuss two types of mediators:the dark photon A’ and the dark scalar mediator Φ .The total cross-sections and various differential ...Dark sector may couple to the Standard Model via one or more mediator particles.We discuss two types of mediators:the dark photon A’ and the dark scalar mediator Φ .The total cross-sections and various differential distributions of the processes e+e-→qqA’ and e+e→qqφ（q=u,d,c,s and b quarks） are discussed.We focus on the study of the invisible due to the cleaner background at future e+e-colliders.It is found that the kinematic distributions of the two-jet system could be used to identify（or exclude） the dark photon and the dark scalar mediator,as well as to distinguish between them.We further study the possibility of a search for dark photons at a future CEPC experiment with s1/2=91.2 GeV and 240 GeV.With CEPC running at s1/2=91.2 GeV,it would be possible to perform a decisive measurement of the dark photon（20 GeV <mA’ <60 GeV） in less than one operating year.The lower limits of the integrated luminosity for the significance S/B1/2=2σ,3σ and 5σ are presented.展开更多
The W-boson mass(m W=(80.4335±0.0094)Ge V)measured by the Collider Detector at Fermilab Collaboration is greater than the standard model(SM)prediction at a confidence level of 7σ,strongly suggesting the presence...The W-boson mass(m W=(80.4335±0.0094)Ge V)measured by the Collider Detector at Fermilab Collaboration is greater than the standard model(SM)prediction at a confidence level of 7σ,strongly suggesting the presence of new particles or fields.In the literature,various new particles and/or fields have been introduced to explain the astrophysical and experimental data,and their presence,in principle,may also enhance the W-boson mass.In this study,we investigate axion-like particle(ALP),dark photon(DP),and chameleon dark energy(DE)models for a solution to the W-boson mass excess.We find that the ALP and DP interpretations have been significantly narrowed down by global electroweak fits.The possibility of attributing the W-boson mass anomaly to the chameleon DE is ruled out by other experiments.展开更多
We propose searching for dark photon signals in the decay channel of η mesons,specifically through the leptonic decay(A'→e^(+)e^(-)(μ^(+)μ^(-)))observable in photon-photon interactions during ultra-peripheral ...We propose searching for dark photon signals in the decay channel of η mesons,specifically through the leptonic decay(A'→e^(+)e^(-)(μ^(+)μ^(-)))observable in photon-photon interactions during ultra-peripheral heavy-ion collisions.We estimate the total cross-section for dark photon production in ultra-peripheral PbPb collisions at current and future hadron colliders.Our findings support the potential for detecting dark photon signals at the LHC,HighLuminosity LHC,High-Energy LHC,and Future Circular Collider.展开更多
Spring water but not double-distilled water was exposed, in darkness, to a temporally patterned weak magnetic field that has been shown to affect planarian behavior and slow the rate of cancer cell proliferation. Expo...Spring water but not double-distilled water was exposed, in darkness, to a temporally patterned weak magnetic field that has been shown to affect planarian behavior and slow the rate of cancer cell proliferation. Exposure to the magnetic field caused a reliable shift in the peak (longer) wave-length of ~10 nm for fluorescence emissions and a ~20% increase (~100 counts) in fluorescence intensity. Spectral analyses verified a shift of 5 and 10 nm, equivalent to ~1.5 × 10-20 J “periodicity” across the measured wavelengths, which could reflect a change in the an intrinsic energy as predicted by Del Giudice and Preparata and could correspond to two lengths of O-H bonds. Wrapping the water sample containers during exposure with copper foil, aluminum foil, or plastic altered these fluorescent profiles. The most conspicuous effect was the elimination of a ~280 nm peak in the UV-VIS emission spectra only for samples wrapped with copper foil but not aluminum or plastic. These results suggest that weak magnetic fields produce alterations in the water-ionic complexes sufficient to be reliably measured by spectrophotometry. Because the effect was most pronounced when the spring water was exposed in darkness and was not disturbed the role of thixotropic phenomena and Del Giudice entrapment of magnetic fields within coherent domains of Pollack virtual exclusion zones (EZ) may have set the conditions for subsequent release of the energy as photons.展开更多
This paper proposes two optimal designs of single photon avalanche diodes(SPADs) minimizing dark count rate(DCR). The first structure is introduced as p^+/pwell/nwell, in which a specific shallow pwell layer is added ...This paper proposes two optimal designs of single photon avalanche diodes(SPADs) minimizing dark count rate(DCR). The first structure is introduced as p^+/pwell/nwell, in which a specific shallow pwell layer is added between p^+and nwell layers to decrease the electric field below a certain threshold. The simulation results show on average 19.7%and 8.5% reduction of p^+/nwell structure’s DCR comparing with similar previous structures in different operational excess bias and temperatures respectively. Moreover, a new structure is introduced as n+/nwell/pwell, in which a specific shallow nwell layer is added between n+and pwell layers to lower the electric field below a certain threshold. The simulation results show on average 29.2% and 5.5% decrement of p^+/nwell structure’s DCR comparing with similar previous structures in different operational excess bias and temperatures respectively. It is shown that in higher excess biases(about 6 volts), the n+/nwell/pwell structure is proper to be integrated as digital silicon photomultiplier(dSiPM) due to low DCR. On the other hand, the p^+/pwell/nwell structure is appropriate to be utilized in dSiPM in high temperatures(above 50?C) due to lower DCR value.展开更多
What exactly are photons and dark matter? Modern physical theories do not explain them very well. In this paper, by extending the law of electromagnetic oscillation, the space particles and their operation law can als...What exactly are photons and dark matter? Modern physical theories do not explain them very well. In this paper, by extending the law of electromagnetic oscillation, the space particles and their operation law can also be obtained. The system of space particle theory is formed under the law of physics. The conclusion of the theory of space particles is quite consistent with many physical phenomena. There are no contradictions that can be found. According to the theory of space particles, there is an uneven space at the edge of an object, which has been proved by a series of experimental phenomena. The theory of space particles has revealed the essence of photons and dark matter. It has also revealed the relationship between space, mass, and energy. Space is a physical phenomenon.展开更多
This paper reports that, based on the electromagnetic scattering theory of the multipole method, a high-quality hollow beam is produced through a selectively liquid-filled photonic crystal fibre. Instead of a doughnut...This paper reports that, based on the electromagnetic scattering theory of the multipole method, a high-quality hollow beam is produced through a selectively liquid-filled photonic crystal fibre. Instead of a doughnut shape, a typical hollow beam is produced by other methods; the mode-field images of the hollow-beam photonic crystal fibre satisfy sixth-order rotation symmetry, according to the symmetry of the photonic crystal fibre （PCF） structure. A dark spot size of the liquid-filled photonic crystal fibre-generated hollow beam can be tuned by inserting liquid into the cladding region and varying the photonic crystal fibre structure parameters. The liquid-filled PCF makes a convenient and flexible tool for the guiding and trapping of atoms and the creation of all-fibre optical tweezers.展开更多
The sensitivity of the dark photon search through invisible decay final states in low-background experiments relies sig-nificantly on the neutron and muon veto efficiencies,which depend on the amount of material used ...The sensitivity of the dark photon search through invisible decay final states in low-background experiments relies sig-nificantly on the neutron and muon veto efficiencies,which depend on the amount of material used and the design of the detector geometry.This paper presents the optimized design of the hadronic calorimeter(HCAL)used in the DarkSHINE experiment,which is studied using a GEANT4-based simulation framework.The geometry is optimized by comparing a traditional design with uniform absorbers to one that uses different thicknesses at different locations on the detector,which enhances the efficiency of vetoing low-energy neutrons at the sub-GeV level.The overall size and total amount of material used in the HCAL are optimized to be lower,owing to the load and budget requirements,whereas the overall performance is studied to satisfy the physical objectives.展开更多
This article presents the hypothesis that the vacuum is endowed with a quantum structure;the vacuum particles would be Friedmann-Planck micro-universes. For this, the article introduces a quantization of a closed Frie...This article presents the hypothesis that the vacuum is endowed with a quantum structure;the vacuum particles would be Friedmann-Planck micro-universes. For this, the article introduces a quantization of a closed Friedmann universe, then a quantization of the photon spheres filling this universe. This approach gives a numerical value consistent with cosmological measurements for the current dark energy density of our Universe. Next, the article takes the content of a model published in Physics Essays in 2013 [<a href="#ref1" target="_blank">1</a>], assuming that elementary particles are Schwarzschild photon spheres;these could be derived from the Friedmann photon spheres composing the vacuum particles. It is further recalled that the model presents a unified structure of elementary particles and allows us to calculate the value of the elementary electric charge as well as the mass of the elementary particles.展开更多
A rigorous theoretical model for Ino.53Gao.47As/InP single photon avalanche diode is utilized to investigate the dependences of single photon quantum efficiency and dark count probability on structure and operation co...A rigorous theoretical model for Ino.53Gao.47As/InP single photon avalanche diode is utilized to investigate the dependences of single photon quantum efficiency and dark count probability on structure and operation condition. In the model, low field impact ionizations in charge and absorption layers are allowed, while avalanche breakdown can occur only in the multiplication layer. The origin of dark counts is discussed and the results indicate that the dominant mechanism that gives rise to dark counts depends on both device structure and operating condition. When the multiplication layer is thicker than a critical thickness or the temperature is higher than a critical value, generation-recombination in the absorption layer is the dominative mechanism; otherwise band-to-band tunneling in the multiplication layer dominates the dark counts. The thicknesses of charge and multiplication layers greatly affect the dark count and the peak single photon quantum efficiency and increasing the multiplication layer width may reduce the dark count probability and increase the peak single photon quantum efficiency. However, when the multiplication layer width exceeds 1 μm, the peak single photon quantum efficiency increases slowly and it is finally saturated at the quantum efficiency of the single photon avalanche diodes.展开更多
We present Dark Matter candidates from non SUSY processes, in a way emphasizing how a Dark Matter (DM) candidate of roughly 100 - 400 GeV could be formed. As has been said about the Photon rocket and Axions rockets, t...We present Dark Matter candidates from non SUSY processes, in a way emphasizing how a Dark Matter (DM) candidate of roughly 100 - 400 GeV could be formed. As has been said about the Photon rocket and Axions rockets, the presence of a magnetic field supposedly would switch DM particle candidates to photons, in such a way as to in the end configure a photon rocket style device from DM in a thrust chamber. The presence of Dark Matter (DM) would in itself merely indicate that the emerging photon thrust would be comparatively greater than it would be for more conventional photon rockets. This amplifies and improves upon a so called axion rocket ram jet for interstellar travel. We assume that much the same sort of methodology for a would-be axion ramjet could be employed for DM, with perhaps greater thrust/power conversion efficiencies.展开更多
A simple assumption for dark matter leads to magnetic-monopole-like terms to Maxwell’s Equations, a photon model with wave-particle duality, nuclear stability, a decelerating expansion of the universe, and a dark-mat...A simple assumption for dark matter leads to magnetic-monopole-like terms to Maxwell’s Equations, a photon model with wave-particle duality, nuclear stability, a decelerating expansion of the universe, and a dark-matter relativity that defines the origin of space and time.展开更多
At present, the research of single-photon is a hot topic, it has been widely applied in quantum measurement, quantum entanglement and quantum information. In this paper, we have proposed a new single photon theory, wh...At present, the research of single-photon is a hot topic, it has been widely applied in quantum measurement, quantum entanglement and quantum information. In this paper, we have proposed a new single photon theory, which is the vector potential A rotation at the vertical motion direction of photon, it can produce the microscopic electric field and magnetic field, and they satisfy the Maxwell equations. We have calculated photon spin, momentum, energy, and found there are left-handed and right-handed photon. In addition, we study the multi-photon theory and the dynamics theory between photons interaction. On this basis, we have further given the compound structures of electron, proton, neutron, neutrino, π meson, dark matter with the photon structural theory, and calculated their mass, charge and spin.展开更多
基金supported by National Key R&D Program of China(Nos.2023YFA1606904 and 2023YFA1606900)National Natural Science Foundation of China(No.12150006)+1 种基金Shanghai Pilot Program for Basic Research-Shanghai Jiao Tong University(No.21TQ1400209)National Center for High-Level Talent Training in Mathematics,Physics,Chemistry,and Biology。
文摘This paper presents the design and optimization of a lutetium yttrium oxyorthosilicate(LYSO)crystal electromagnetic calorimeter(ECAL)for the DarkSHINE experiment,which aims to identify dark photons as potential mediators of dark forces.The ECAL design was evaluated through comprehensive simulations,focusing on optimizing dimensions,material selection,energy distribution,and energy resolution.The configuration consisted of 21×21×11 LYSO crystals,each measuring 2.5 cm×2.5 cm×4 cm,arranged in a staggered layout to enhance signal detection efficiency.A 4 GeV energy dynamic range was established to ensure accurate energy measurements without saturation,which is essential for background rejection and signal identification.A detailed digitization model was developed to simulate scintillation,silicon photomultiplier,and analog-to-digital converter behaviors,providing a realistic representation of the detector's performance.Additionally,the study assessed radiation damage in the ECAL region,emphasizing the importance of using radiation-resistant scintillators and silicon sensors.
基金supported in part by the National Natural Science Foundation of China under Grant Nos.11875157,12147214the Doctoral Start-up Fund of Liaoning Normal University under Grant No.2024BSL018the Universitylevel National Research Project Cultivation Program under Grant No.2024170。
文摘The massless dark photon~γ can only interact with the Standard Model(SM)sector via higherdimensional operators.In this letter,we investigate its production associated with the ordinary photonγfrom the lepton flavor violation(LFV)process l_(i)→l_(j)γγ and di-production from the LFV process l_(i)→l_(j)γγ induced by dipole operators.Comparing the obtained numerical results with the corresponding experimental measurements,we obtain the constraints on the effective couplings of γ with the SM charged leptons.The upper limit of the effective coupling|DLμe|2+|DRμe|2coming from the process μ→e~γγis looser than the processμ→eγ by about one order of magnitude.
基金National Key Research and Development Program of China(2020YFC2201501)Yifan Chen was supported by VILLUM FONDEN(37766)+4 种基金Danish Research Foundation,and under the European Union’s H2020 ERC Advanced Grant“Black holes:gravitational engines of discovery”grant agreement(Gravitas–101052587)European Consortium for Astroparticle Theory in the form of an Exchange Travel Grant,and by FCT(Fundação para a Ciência e Tecnologia I.P,Portugal)(2022.01324.PTDC)Jing Shu was supported by the National Natural Science Foundation of China(12025507,12450006,and.12150015)Peking University under startup Grant(7101302974)State Key Laboratory of Nuclear Physics and Technology,Peking University(NPT2024ZX01).
文摘Dark photons,as a minimal extension of the Standard Model through an additional Abelian gauge group,may propagate relativistically across the galaxy,originating from dark matter decay or annihilation,thereby contributing to a galactic dark photon background.The generation of dark photons typically favors certain polarization modes,which are dependent on the interactions between dark matter and dark photons.We introduce a framework in which a resonant cavity is utilized to detect and differentiate these polarizations,leveraging the daily variation in expected signals due to the anisotropic distribution of dark photons and the rotation of the Earth.We conduct an experimental search using superconducting radio-frequency cavities,noted for their exceptionally high quality factors,proving them to be effective telescopes for observing galactic dark photons.This approach establishes the most stringent limits yet on the kinetic mixing coefficient between dark photons and electromagnetic photons,thereby unveiling a novel avenue for the indirect search for dark matter via multi-messenger astronomy.
基金supported by the National Natural Science Foundation of China(12375096,12035008,11975129)。
文摘The ultralight dark photon is an intriguing dark matter candidate.The interaction between visible and dark photons is introduced by the gauge kinetic mixing between the field strength tensors of the Abelian gauge groups in the Standard Model and dark sector.Relativistic electrodynamics was generalized to quantum electromagnetodynamics(QEMD)in the presence of both electric and magnetic charges.The photon is described by two fourpotentials corresponding to two U(1)gauge groups and satisfying non-trivial commutation relations.In this work,we construct low-energy dark photon-photon interactions in the QEMD framework and obtain new dark photonphoton kinetic mixings.Then,we derive the consequent field and Maxwell's equations.We also investigate the detection strategies of dark photons as light dark matter and generic kinetic mixings at haloscope experiments.
基金Supported by the Fundamental Research Funds for the Central Universities(Takaaki Nomura)。
文摘We discuss almost degenerate vector dark matter and dark photonsinduced from the hidden SU(2)Hgauge sector,where it is spontaneously broken by the vacuum expectation value of SU(2)Hdoublet.Kinetic mixing between SU(2)Hand U(1)Ygauge fields can be generated by introducing a dimension six operator realizing dark photon interactions.In estimating relic density,we focus on the process in which dark matter annihilates into dark photons and search for the region of dark matter mass and gauge coupling realizing observed relic density.We then discuss constraints from dark photon physics,thermalization of dark sector,and direct detection of dark matter.It is then found that constraints from direct detection experiments give us the strongest upper limits on the dark photon interactions.
基金supported by the National Key Research and Development Program of China under Grant No.2020YFC2201501YOUTH INNOVATION PROMOTION ASSOCIATION CAS NO.292022000038+1 种基金Jing Shu is supported by Peking University under startup Grant No.7101302974the National Natural Science Foundation of China under Grants No.12025507 and No.12150015 and is supported by the Key Research Program of Frontier Science of the Chinese Academy of Sciences(CAS)under Grants No.ZDBS-LY-7003.
文摘Purpose In order to precisely control the resonant frequency of RF superconducting cavity to detect dark photon dark matter,and to be able to tune within a certain frequency range,it is necessary to design a low-temperature tuner for frequency control on the bare cavity.Methods Two type mechanical tuners have been designed for the 1.3 GHz single-cell bare cavity and 650 MHz single cell bare cavity.The tuner device tunes the frequency of RF superconducting cavity for the detection of dark photons and dark matter and measures its tuning range and accuracy in both room-temperature and low-temperature environments.Results The tuner for the 1.3 GHz cavity has a tuning accuracy of 1 Hz per step and a tuning range of 1.37 MHz at low temperature.The tuner for the 650 MHz cavity has a tuning range of 467 kHz at low temperatures,with a tuning accuracy of 1.77 Hz per step.Conclusion The designed tuner can meet the requirements of RF superconducting cavity tuning for detecting dark photons and dark matter,and its adjustable range,precision and stability ensure that the detection experiment can be carried out smoothly.
文摘In this paper, we derive the bright and dark photon number states for spatial interference of two or more light beams and succeed in the explanation of Young's interference experiment, and also achieve a better comprehension of the well known comment of Dirac 'each photon only interferences with itself'. Prom the fully quantum point of view, the origin of the interference fringes consists in the mode transformation and the detection of double-slit states.
基金supported in part by the National Natural Science Foundation of China(11875179,11325525,11635009,11775130,11905112)the Natural Science Foundation of Shandong Province(ZR2017MA002,ZR2019QA012)the Fundamental Research Funds of Shandong University(2019GN038)
文摘Dark sector may couple to the Standard Model via one or more mediator particles.We discuss two types of mediators:the dark photon A’ and the dark scalar mediator Φ .The total cross-sections and various differential distributions of the processes e+e-→qqA’ and e+e→qqφ（q=u,d,c,s and b quarks） are discussed.We focus on the study of the invisible due to the cleaner background at future e+e-colliders.It is found that the kinematic distributions of the two-jet system could be used to identify（or exclude） the dark photon and the dark scalar mediator,as well as to distinguish between them.We further study the possibility of a search for dark photons at a future CEPC experiment with s1/2=91.2 GeV and 240 GeV.With CEPC running at s1/2=91.2 GeV,it would be possible to perform a decisive measurement of the dark photon（20 GeV <mA’ <60 GeV） in less than one operating year.The lower limits of the integrated luminosity for the significance S/B1/2=2σ,3σ and 5σ are presented.
基金supported by the National Key R&D Program of China(Grant No.2021YFC2203100)the National Natural Science Foundation of China(Grant Nos.11921003,11961131007,and 11653002)+1 种基金the CAS Project for Young Scientists in Basic Research(Grant No.YSBR-006)the USTC Research Funds of the Double First-Class Initiative。
文摘The W-boson mass(m W=(80.4335±0.0094)Ge V)measured by the Collider Detector at Fermilab Collaboration is greater than the standard model(SM)prediction at a confidence level of 7σ,strongly suggesting the presence of new particles or fields.In the literature,various new particles and/or fields have been introduced to explain the astrophysical and experimental data,and their presence,in principle,may also enhance the W-boson mass.In this study,we investigate axion-like particle(ALP),dark photon(DP),and chameleon dark energy(DE)models for a solution to the W-boson mass excess.We find that the ALP and DP interpretations have been significantly narrowed down by global electroweak fits.The possibility of attributing the W-boson mass anomaly to the chameleon DE is ruled out by other experiments.
基金Supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDB34030301)。
文摘We propose searching for dark photon signals in the decay channel of η mesons,specifically through the leptonic decay(A'→e^(+)e^(-)(μ^(+)μ^(-)))observable in photon-photon interactions during ultra-peripheral heavy-ion collisions.We estimate the total cross-section for dark photon production in ultra-peripheral PbPb collisions at current and future hadron colliders.Our findings support the potential for detecting dark photon signals at the LHC,HighLuminosity LHC,High-Energy LHC,and Future Circular Collider.
文摘Spring water but not double-distilled water was exposed, in darkness, to a temporally patterned weak magnetic field that has been shown to affect planarian behavior and slow the rate of cancer cell proliferation. Exposure to the magnetic field caused a reliable shift in the peak (longer) wave-length of ~10 nm for fluorescence emissions and a ~20% increase (~100 counts) in fluorescence intensity. Spectral analyses verified a shift of 5 and 10 nm, equivalent to ~1.5 × 10-20 J “periodicity” across the measured wavelengths, which could reflect a change in the an intrinsic energy as predicted by Del Giudice and Preparata and could correspond to two lengths of O-H bonds. Wrapping the water sample containers during exposure with copper foil, aluminum foil, or plastic altered these fluorescent profiles. The most conspicuous effect was the elimination of a ~280 nm peak in the UV-VIS emission spectra only for samples wrapped with copper foil but not aluminum or plastic. These results suggest that weak magnetic fields produce alterations in the water-ionic complexes sufficient to be reliably measured by spectrophotometry. Because the effect was most pronounced when the spring water was exposed in darkness and was not disturbed the role of thixotropic phenomena and Del Giudice entrapment of magnetic fields within coherent domains of Pollack virtual exclusion zones (EZ) may have set the conditions for subsequent release of the energy as photons.
文摘This paper proposes two optimal designs of single photon avalanche diodes(SPADs) minimizing dark count rate(DCR). The first structure is introduced as p^+/pwell/nwell, in which a specific shallow pwell layer is added between p^+and nwell layers to decrease the electric field below a certain threshold. The simulation results show on average 19.7%and 8.5% reduction of p^+/nwell structure’s DCR comparing with similar previous structures in different operational excess bias and temperatures respectively. Moreover, a new structure is introduced as n+/nwell/pwell, in which a specific shallow nwell layer is added between n+and pwell layers to lower the electric field below a certain threshold. The simulation results show on average 29.2% and 5.5% decrement of p^+/nwell structure’s DCR comparing with similar previous structures in different operational excess bias and temperatures respectively. It is shown that in higher excess biases(about 6 volts), the n+/nwell/pwell structure is proper to be integrated as digital silicon photomultiplier(dSiPM) due to low DCR. On the other hand, the p^+/pwell/nwell structure is appropriate to be utilized in dSiPM in high temperatures(above 50?C) due to lower DCR value.
文摘What exactly are photons and dark matter? Modern physical theories do not explain them very well. In this paper, by extending the law of electromagnetic oscillation, the space particles and their operation law can also be obtained. The system of space particle theory is formed under the law of physics. The conclusion of the theory of space particles is quite consistent with many physical phenomena. There are no contradictions that can be found. According to the theory of space particles, there is an uneven space at the edge of an object, which has been proved by a series of experimental phenomena. The theory of space particles has revealed the essence of photons and dark matter. It has also revealed the relationship between space, mass, and energy. Space is a physical phenomenon.
基金Project supported in part by the National Natural Science Foundation of China(Grant No.10874145)the Specialized Research Fund for Doctorial Program of Higher Education(Grant No.20091333110010)+1 种基金the Natural Science Foundation of Heibei Province, China(Grant No.F2009000481)the China Postdoctoral Science Foundation(Grant Nos.20080440014 and 200902046)
文摘This paper reports that, based on the electromagnetic scattering theory of the multipole method, a high-quality hollow beam is produced through a selectively liquid-filled photonic crystal fibre. Instead of a doughnut shape, a typical hollow beam is produced by other methods; the mode-field images of the hollow-beam photonic crystal fibre satisfy sixth-order rotation symmetry, according to the symmetry of the photonic crystal fibre （PCF） structure. A dark spot size of the liquid-filled photonic crystal fibre-generated hollow beam can be tuned by inserting liquid into the cladding region and varying the photonic crystal fibre structure parameters. The liquid-filled PCF makes a convenient and flexible tool for the guiding and trapping of atoms and the creation of all-fibre optical tweezers.
基金supported by National Key R&D Program of China(Nos.2023YFA1606904 and 2023YFA1606900)National Natural Science Foundation of China(No.12150006)Shanghai Pilot Program for Basic Research-Shanghai Jiao Tong University(No.21TQ1400209).
文摘The sensitivity of the dark photon search through invisible decay final states in low-background experiments relies sig-nificantly on the neutron and muon veto efficiencies,which depend on the amount of material used and the design of the detector geometry.This paper presents the optimized design of the hadronic calorimeter(HCAL)used in the DarkSHINE experiment,which is studied using a GEANT4-based simulation framework.The geometry is optimized by comparing a traditional design with uniform absorbers to one that uses different thicknesses at different locations on the detector,which enhances the efficiency of vetoing low-energy neutrons at the sub-GeV level.The overall size and total amount of material used in the HCAL are optimized to be lower,owing to the load and budget requirements,whereas the overall performance is studied to satisfy the physical objectives.
文摘This article presents the hypothesis that the vacuum is endowed with a quantum structure;the vacuum particles would be Friedmann-Planck micro-universes. For this, the article introduces a quantization of a closed Friedmann universe, then a quantization of the photon spheres filling this universe. This approach gives a numerical value consistent with cosmological measurements for the current dark energy density of our Universe. Next, the article takes the content of a model published in Physics Essays in 2013 [<a href="#ref1" target="_blank">1</a>], assuming that elementary particles are Schwarzschild photon spheres;these could be derived from the Friedmann photon spheres composing the vacuum particles. It is further recalled that the model presents a unified structure of elementary particles and allows us to calculate the value of the elementary electric charge as well as the mass of the elementary particles.
基金supported by the National Basic Research Program of China (Grant Nos. G2001039302 and 007CB307001)the Guangdong Provincial Key Technology Research and Development Program,China (Grant No. 2007B010400009)
文摘A rigorous theoretical model for Ino.53Gao.47As/InP single photon avalanche diode is utilized to investigate the dependences of single photon quantum efficiency and dark count probability on structure and operation condition. In the model, low field impact ionizations in charge and absorption layers are allowed, while avalanche breakdown can occur only in the multiplication layer. The origin of dark counts is discussed and the results indicate that the dominant mechanism that gives rise to dark counts depends on both device structure and operating condition. When the multiplication layer is thicker than a critical thickness or the temperature is higher than a critical value, generation-recombination in the absorption layer is the dominative mechanism; otherwise band-to-band tunneling in the multiplication layer dominates the dark counts. The thicknesses of charge and multiplication layers greatly affect the dark count and the peak single photon quantum efficiency and increasing the multiplication layer width may reduce the dark count probability and increase the peak single photon quantum efficiency. However, when the multiplication layer width exceeds 1 μm, the peak single photon quantum efficiency increases slowly and it is finally saturated at the quantum efficiency of the single photon avalanche diodes.
文摘We present Dark Matter candidates from non SUSY processes, in a way emphasizing how a Dark Matter (DM) candidate of roughly 100 - 400 GeV could be formed. As has been said about the Photon rocket and Axions rockets, the presence of a magnetic field supposedly would switch DM particle candidates to photons, in such a way as to in the end configure a photon rocket style device from DM in a thrust chamber. The presence of Dark Matter (DM) would in itself merely indicate that the emerging photon thrust would be comparatively greater than it would be for more conventional photon rockets. This amplifies and improves upon a so called axion rocket ram jet for interstellar travel. We assume that much the same sort of methodology for a would-be axion ramjet could be employed for DM, with perhaps greater thrust/power conversion efficiencies.
文摘A simple assumption for dark matter leads to magnetic-monopole-like terms to Maxwell’s Equations, a photon model with wave-particle duality, nuclear stability, a decelerating expansion of the universe, and a dark-matter relativity that defines the origin of space and time.
文摘At present, the research of single-photon is a hot topic, it has been widely applied in quantum measurement, quantum entanglement and quantum information. In this paper, we have proposed a new single photon theory, which is the vector potential A rotation at the vertical motion direction of photon, it can produce the microscopic electric field and magnetic field, and they satisfy the Maxwell equations. We have calculated photon spin, momentum, energy, and found there are left-handed and right-handed photon. In addition, we study the multi-photon theory and the dynamics theory between photons interaction. On this basis, we have further given the compound structures of electron, proton, neutron, neutrino, π meson, dark matter with the photon structural theory, and calculated their mass, charge and spin.
