Source string | Question string | Answer string | Question_type string | Referenced_file(s) string | chunk_text string | expert_annotation string | specific to paper string | Label int64 |
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expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | $$ where the bunch length $l$ is $$ l = \\frac { \\frac { \\pi } { 2 } + \\sqrt { \\mathcal { R } ^ { 2 } - 1 } - 1 } { k _ { n } } . $$ Evaluating the form factor at $k = k _ { n }$ produces $$ | F ( k _ { n } ) | = \\frac { 2 \\mathcal { R } } { \\mathcal { R } ^ { 2 } + \\pi - 2 } . $$ This result leads to the accel... | 1 | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | With the minor radius and frequency selected, the corrugation profile is chosen to maximize the accelerating gradient as well as provide a high repetition rate. The $1 \\mathrm { - m m }$ minor radius of the CWG results in corrugation dimensions in the hundreds of $\\mu \\mathrm { m }$ which presents unique manufacturi... | 2 | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | APPENDIX A: SCALING AND NORMALIZATION Here, we derive the scaling laws for the loss factor $\\kappa$ , group velocity $\\beta _ { g } ,$ and attenuation constant $\\alpha$ . We will assume that $\\sigma$ satisfies the conditions of a good conductor so that the field solutions are independent of conductivity. The time h... | 1 | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | $$ We will now consider the effect of the bunch charge density $q ( s )$ on the accelerating field $E _ { z } ( s )$ in order to understand how $E _ { \\mathrm { a c c } }$ and the peak surface fields depend on $q ( s )$ . To begin, we write $E _ { z , n }$ due to a single mode as a convolution $$ E _ { z , n } ( s ) =... | augmentation | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | $$ q ( s ) = N \\times { \\left\\{ \\begin{array} { l l } { 1 } & { 0 < s < \\pi / ( 2 k _ { n } ) } \\\\ { k _ { n } s + ( 1 - \\pi / 2 ) } & { \\pi / ( 2 k _ { n } ) < s < l } \\\\ { 0 } & { { \\mathrm { e l s e } } } \\end{array} \\right. } $$ where $s$ is the longitudinal displacement from the head of the bunch, $k... | augmentation | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | $$ The integrals in $t$ and $t ^ { \\prime }$ produce Dirac delta functions leaving $$ \\begin{array} { l } { \\displaystyle P _ { w } = \\frac { c } { 2 \\pi } \\mathrm { R e } \\Bigg \\{ \\int _ { - \\infty } ^ { \\infty } d \\omega \\int _ { - \\infty } ^ { \\infty } d \\omega _ { 2 } \\int _ { - \\infty } ^ { \\inf... | augmentation | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | $$ Q = \\frac { \\omega U } { P _ { d } } , $$ where $U$ is stored energy and $P _ { d }$ is the power dissipated in the cavity walls. The power dissipation density per unit area is $$ \\frac { d P _ { d } } { d A } = \\frac { 1 } { 2 } \\sqrt { \\frac { \\omega \\mu } { 2 \\sigma } } | { \\cal H } | ^ { 2 } . $$ In th... | augmentation | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | $$ Q _ { \\mathrm { d i s s } } = \\frac { E _ { \\mathrm { a c c } } ^ { 2 } } { 8 \\alpha \\kappa } ( e ^ { - 2 \\alpha L } + 2 \\alpha L - 1 ) . $$ According to Eq. (14), the amount of energy deposited on the CWG wall per unit length reaches a maximum after the electron bunch propagates a distance $z \\gg 1 / \\alph... | augmentation | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | $$ Here we notice the linear scaling of the energy dissipation with the minor radius, $a$ , which helps smaller diameter structures achieve less heating per pulse and thus higher bunch repetition rates. At a gradient of $E _ { \\mathrm { a c c } } = 9 0 ~ \\mathrm { M V } \\mathrm { m } ^ { - 1 }$ , a minor radius of $... | augmentation | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | $$ E _ { z , n } ( s \\to \\infty ) = 2 \\kappa _ { n } q _ { 0 } \\mathrm { R e } \\{ e ^ { j k _ { n } s } F ( k _ { n } ) \\} $$ Expanding the real part $$ \\begin{array} { r } { E _ { z , n } ( s \\infty ) = 2 \\kappa _ { n } q _ { 0 } [ \\cos ( k _ { n } s ) \\mathrm { R e } \\{ F ( k _ { n } ) \\} } \\\\ { - \\s... | augmentation | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | $$ Since the current density $i ( t )$ is a purely real function, $I ( - \\omega ) = I ^ { * } ( \\omega )$ where $*$ denotes complex conjugation, leading to $$ P _ { \\nu } = \\frac { c } { 2 \\pi } \\int _ { - \\infty } ^ { \\infty } | I ( \\omega ) | ^ { 2 } \\operatorname { R e } \\{ Z _ { | | } ( \\omega ) \\} d \... | augmentation | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | After determining the minor radius, $a$ , of $1 \\ \\mathrm { m m }$ , the frequency and corresponding aperture ratio of the synchronous $\\mathrm { T M } _ { 0 1 }$ accelerating mode must be chosen. We have shown in Figs. 10 and 12 that the peak surface fields and associated pulse heating increase with aperture ratio ... | augmentation | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | DOI: 10.1103/PhysRevAccelBeams.25.121601 I. INTRODUCTION A sub-terahertz accelerator (A-STAR) is being developed at Argonne National Laboratory to reduce the cost and footprint of a future hard x-ray free-electron laser (XFEL) facility [1,2]. A-STAR is a collinear wakefield accelerator (CWA) that uses a cylindrical cor... | augmentation | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | $$ \\frac { E _ { \\mathrm { m a x } } ^ { 3 0 } t _ { p } ^ { 5 } } { \\mathrm { B D R } } = \\mathrm { c o n s t . } $$ From a design perspective, reducing the BDR is achieved by reducing the peak surface fields and the pulse length. Calculation of the absolute threshold value of the fields that induce breakdown in s... | augmentation | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | $$ \\begin{array} { l } { { \\displaystyle E _ { z } ( s ) = \\int _ { - \\infty } ^ { \\infty } q ( s - s ^ { \\prime } ) h ( s ^ { \\prime } ) d s ^ { \\prime } } } \\\\ { { \\displaystyle h ( s ) = \\sum _ { n = 0 } ^ { \\infty } 2 \\kappa _ { n } \\cos { ( k _ { n } s ) } \\theta ( s ) . } } \\end{array} $$ The wak... | augmentation | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | VI. THERMAL LOADING Thermal loading of the corrugated waveguide places a limit on the maximum repetition rate $f _ { r }$ of the accelerator, where $f _ { r }$ is the number of bunches injected into the structure per second. The thermal loading depends on the electromagnetic properties of the $\\mathrm { T M } _ { 0 1 ... | augmentation | Yes | 0 |
expert | What effect does reducing the corrugation period have? | reduces peak surface fields, heating & HOMs | Summary | Design_of_a_cylindrical_corrugated_waveguide.pdf.pdf | Maintaining the fundamental $\\mathrm { T M } _ { 0 1 }$ and $\\mathrm { H E } _ { 1 1 }$ frequencies within a $\\pm 5$ GHz-bandwidth specified by the design of the output couplers requires dimensional tolerances of roughly $\\pm 1 0 ~ { \\mu \\mathrm { m } } ,$ as shown by Fig. 5. The most sensitive dimension to manuf... | augmentation | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | allows to design the spectrum $( \\omega )$ , spatial distribution $\\mathbf { \\Pi } ( \\mathbf { r } )$ , and polarization (e) of radiation by favoring one kind $| \\mathbf { e } { \\cdot } \\mathbf { E } ( \\mathbf { r } , \\omega ) |$ and penalizing others, $- | \\mathbf { e } ^ { \\prime } { \\boldsymbol { \\cdot ... | 1 | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | $$ { \\bf J } ( { \\bf r } , \\omega ) = \\frac { q } { 2 \\pi } { ( 2 \\pi \\sigma _ { x } ^ { 2 } ) } ^ { - 1 / 2 } \\mathrm { e } ^ { - x ^ { 2 } / 2 \\sigma _ { x } ^ { 2 } } \\mathrm { e } ^ { - i k _ { y } y } \\widehat { { \\bf y } } $$ with $k _ { y } = \\omega / \\nu$ . Using this expression, the electromagnet... | 1 | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | Finally, we note that the inverse design was operated with the beam at the center of the $2 6 0 ~ \\mathrm { n m }$ wide channel, whereas the rectangular grating worked at minimal beam-structure distance for maximal efficiency. The simulations assumed the distance $d = 7 0 \\ \\mathrm { n m } .$ , whereas Figure S3 sug... | 1 | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | File Name:haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf Boosting the Efficiency of Smith‚àíPurcell Radiators Using Nanophotonic Inverse Design Urs Haeusler,\\*,‚à• Michael Seidling,\\*,‚à• Peyman Yousefi, and Peter Hommelhoff\\* Cite This: ACS... | 1 | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | 3D Simulations. 3D finite-element-method (FEM) frequency-domain simulations were performed in COMSOL to analyze effects originating from the finite height of the structure and beam. The structures were assumed to be $1 . 5 \\mu \\mathrm { m }$ high on a flat silicon substrate (Figure 1b). The spectral current density h... | 1 | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | A 200-period-long version of the inverse-designed structure was fabricated by electron beam lithography $\\bar { ( } 1 0 0 \\ \\mathrm { k V } )$ and cryogenic reactive-ion etching of $1 - 5 \\Omega \\cdot \\mathrm { c m }$ phosphorus-doped silicon to a depth of $1 . 3 \\big ( 1 \\big ) \\mathsf { \\bar { \\mu } m }$ .... | 4 | Yes | 1 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | KEYWORDS: light‚àímatter interaction, free-electron light sources, Smith‚àíPurcell radiation, inverse design, nanophotonics T ehle Smith‚àíPurcell effect describes the emission of ctromagnetic radiation from a charged particle propagating freely near a periodic structure. The wavelength $\\lambda$ of the far-field radi... | augmentation | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | DESIGN The inverse design optimization was carried out via an opensource Python package34 based on a 2D frequency-domain (FD) simulation. At the center of the optimization process is the objective function $G$ , which formulates the desired performance of the design, defined by the design variable $\\phi$ (Methods). He... | augmentation | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | Figure 2c shows the photon count rate as a function of the electron beam position. Maximum photon count rate is observed when focusing the beam into the channel of the inverse design structure at medium height. The spatial confinement in vertical direction points at the presence of a confined mode, as found in cavities... | augmentation | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | The measurements in Figure 3a show overall a similar performance of the inverse-designed structure and the dual pillar structure. In terms of overall power, the inverse design is with $2 1 . 9 ~ \\mathrm { p W }$ around $12 \\%$ weaker than the dual pillars. This can be understood by the larger channel width of $2 6 0 ... | augmentation | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | For a further study of the different structures, we performed 2D time-domain and 3D frequency-domain simulations. While both time and frequency domain are in principal legitimate ways to calculate the radiation spectrum from single electrons, they differ in computational complexity and precession. The time-domain simul... | augmentation | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | DISCUSSION Comparing the measured emission spectrum of the inverse design to its simulated profile shows that the observed emission was not as powerful and spectrally broader. We identify two causes: First, the electron beam current deteriorates as the beam diverges, where electrons hit the boundaries of the channel an... | augmentation | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | METHODS Inverse Design. The inverse design optimization was carried out via an open-source Python package34 based on a 2D finite-difference frequency-domain (FDFD) simulation at the design angular frequency $\\omega$ corresponding to $\\lambda = 1 . 4 \\mu \\mathrm { m }$ . The simulation cell used for this purpose is ... | augmentation | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | To improve the convergence of the algorithm, we enforced mirror symmetry in $x$ -direction onto the design. This reflects the symmetry of SPR under $\\theta = 9 0 ^ { \\circ }$ and reduces the parameter space by a factor of 2. Furthermore, we observed improved convergence when starting with a large grid spacing $\\left... | augmentation | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | $$ W = \\int _ { S } \\mathrm { d } \\mathbf { A \\cdot } \\int _ { 0 } ^ { \\infty } \\mathrm { d } \\omega ~ \\mathbf { S } ( \\mathbf { r } , \\omega ) , $$ $$ { \\bf S } ( { \\bf r } , \\omega ) = 4 { \\cdot } 2 \\pi \\mathrm { R e } \\left\\{ \\frac { 1 } { 2 } { \\bf E } ( { \\bf r } , \\omega \\omega ) \\times {... | augmentation | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | Numerical Instabilities. We observed that the optimization for a single frequency is very sensitive to numerical instabilities, which is why we optimized our design for multiple frequencies $\\omega _ { i } ( i = 1 , . . . , \\dot { N } )$ simultaneously. A suitable objective function could be the sum over all $G ( \\p... | augmentation | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | Collection Range. The measured Gaussian spectrum from Figure 3a can be explained by the limited numerical aperture of the collection fiber. Smith‚àíPurcell radiation that is emitted in the nonperpendicular direction is offset from the optical axis for collection. This leads to a loss in collection efficiency, which we ... | augmentation | Yes | 0 |
Expert | What electron beam energy was used in the experimental demonstration? | 30 keV | Fact | haeusler-et-al-2022-boosting-the-efficiency-of-smith-purcell-radiators-using-nanophotonic-inverse-design.pdf | 2D time-domain simulation of the rectangular grating (MP4) AUTHOR INFORMATION Corresponding Authors Urs Haeusler − Department Physik, Friedrich-AlexanderUniversität Erlangen-Nürnberg (FAU), Erlangen 91058, Germany; Present Address: Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | g ( \\mathbf { k } ) \\triangleq \\int f ( \\mathbf { r } ) \\mathrm { e } ^ { - i \\mathbf { k } \\cdot \\mathbf { r } } \\mathrm { d } \\mathbf { r } , g ( \\mathbf { r } ) \\triangleq \\frac { 1 } { \\left( 2 \\pi \\right) ^ { 3 } } \\int g ( \\mathbf { k } ) \\mathrm { e } ^ { i \\mathbf { k } \\cdot \\mathbf { r }... | 1 | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | A surprising feature of the limits in equations (4), (5a) and (5b) is their prediction for optimal electron velocities. As shown in Fig. 1c, when electrons are in the far field of the structure $( \\kappa _ { \\rho } d \\gg 1 )$ , stronger photon emission and energy loss are achieved by faster electrons—a well-kn... | 1 | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | free-space optical elements, enabling simultaneous measurement of the spectrum and of the spatial radiation pattern. The SEM used for the experiment was a JEOL JSM-6010LA. Its energy spread at the gun exit was in the range 1.5 to $2 . 5 \\mathrm { e V }$ for the range of acceleration voltages considered in this paper. ... | 4 | Yes | 1 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | The Smith–Purcell effect epitomizes the potential of free-electron radiation. Consider an electron at velocity $\\beta = \\nu / c$ traversing a structure with periodicity $a$ ; it generates far-field radiation at wavelength $\\lambda$ and polar angle $\\theta$ , dictated by2 $$ \\lambda = \\frac { a } { m } \\left( \... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | We begin our analysis by considering an electron (charge $- e$ ) of constant velocity $\\nu \\hat { \\mathbf { x } }$ traversing a generic scatterer (plasmonic or dielectric, finite or extended) of arbitrary size and material composition, as in Fig. 1a. The free current density of the electron, ${ \\bf \\dot { J } } ( ... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | $$ written in cylindrical coordinates $( x , \\rho , \\psi )$ ; here, $K _ { n }$ is the modified Bessel function of the second kind, $k _ { \\nu } = \\omega / \\nu$ and $k _ { \\rho } = \\sqrt { k _ { \\nu } ^ { 2 } - k ^ { 2 } } =$ k/βγ $\\scriptstyle ( k = \\omega / c$ , free-space wavevector; $\\gamma = 1 / \\sqr... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | As recently shown in refs 27–29, for a generic electromagnetic scattering problem, passivity—the condition that polarization currents do no net work—constrains the maximum optical response from a given incident field. Consider three power quantities derived from $\\mathbf { F } _ { \\mathrm { i n c } }$ and the... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | $$ P _ { \\tau } ( \\omega ) \\leq \\frac { \\varepsilon _ { 0 } \\omega \\xi _ { \\tau } } { 2 } \\int _ { V } \\mathbf { F } _ { \\mathrm { i n } } ^ { \\dagger } \\overline { { \\overline { { \\chi } } } } ^ { \\dagger } ( \\mathrm { I m } \\overline { { \\overline { { \\chi } } } } ) ^ { - 1 } \\overline { { \\over... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | Combining equations (2) and (3) yields a general limit on the loss or emission spectral probabilities $\\bar { T _ { \\tau } } ( \\omega ) = \\bar { P _ { \\tau } } ( \\omega ) / \\hbar \\omega$ : $$ \\Gamma _ { \\tau } ( \\omega ) \\leq \\frac { \\alpha \\xi _ { \\tau } c } { 2 \\pi \\omega ^ { 2 } } \\int _ { V } \\f... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | The limit in equation (4) can be further simplified by removing the shape dependence of $V$ , since the integrand is positive and is thus bounded above by the same integral for any enclosing structure. A scatterer separated from the electron by a minimum distance $d$ can be enclosed within a larger concentric hollow cy... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | $$ $$ \\propto \\frac { 1 } { \\beta ^ { 2 } } \\Bigg \\{ \\ln ( 1 / \\kappa _ { \\rho } d ) \\mathrm { f o r } \\kappa _ { \\rho } d \\ll 1 , $$ The limits of equations (4), (5a) and (5b) are completely general; they set the maximum photon emission and energy loss of an electron beam coupled to an arbitrary photonic e... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | Next, we specialize in the canonical Smith–Purcell set-up illustrated in Fig. 1e inset. This set-up warrants a particularly close study, given its prominent historical and practical role in free-electron radiation. Aside from the shape-independent limit (equations (5a) and (5b)), we can find a sharper limit (in per u... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | The grating limit (equation (6)) exhibits the same asymptotics as equations (5a) and (5b), thereby reinforcing the optimal-velocity predictions of Fig. 1c. The $( \\beta , k \\dot { d } )$ dependence of $\\mathcal { G }$ (see Fig. 2a) shows that slow (fast) electrons maximize Smith–Purcell radiation in the small (lar... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | Finally, we turn our attention to an ostensible peculiarity of the limits: equation (4) evidently diverges for lossless materials $( \\mathrm { I m } \\chi \\to 0 ) \\dot { { \\frac { . } { . } } }$ ), seemingly providing little insight. On the contrary, this divergence suggests the existence of a mechanism capable of ... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | To overcome this deficiency, we theoretically propose a new mechanism for enhanced Smith–Purcell radiation: coupling of electrons with $\\mathrm { B I C } s ^ { 1 3 }$ . The latter have the extreme quality factors of guided modes but are, crucially, embedded in the radiation continuum, guaranteeing any resulting Smit... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | The BIC-enhancement mechanism is entirely accordant with our upper limits. Practically, silicon has non-zero loss across the visible and near-infrared wavelengths. For example, for a period of $a = 6 7 6 \\mathrm { n m }$ , the optimally enhanced radiation wavelength is $\\approx 1 { , } 0 5 0 \\mathrm { n m }$ , at wh... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | The upper limit demonstrated here is in the spontaneous emission regime for constant-velocity electrons, and can be extended to the stimulated regime by suitable reformulation. Stronger electron– photon interactions can change electron velocity by a non-negligible amount that alters the radiation. If necessary, this ... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | Author contributions Y.Y., O.D.M., I.K. and M.S. conceived the project. Y.Y. developed the analytical models and numerical calculations. A.M. prepared the sample under study. Y.Y., A.M., C.R.-C., S.E.K. and I.K. performed the experiment. Y.Y., T.C. and O.D.M. analysed the asymptotics and bulk loss of the limit. S.G.J.,... | augmentation | Yes | 0 |
Expert | What experimental structure was used to validate the theoretical upper limit with Smith-Purcell measurements? | A one-dimensional, 50%-filling-factor, Au-covered single-crystalline silicon grating. | Fact | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | Data availability. The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request. | augmentation | Yes | 0 |
Expert | What general limit does Equation (4) impose on free-electron radiation? | It establishes a shape-independent upper limit on the spectral probabilities of energy loss and photon emission by free electrons in any photonic environment. | Definition | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | File Name:Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf Maximal spontaneous photon emission and energy loss from free electrons Yi Yang $\\textcircled { 1 0 } 1 \\star$ , Aviram Massuda1, Charles Roques-Carmes $\\oplus 1$ , Steven E. Kooi $\\oplus 2$ , Thomas Christensen1, Steven G. Johnso... | 1 | Yes | 0 |
Expert | What general limit does Equation (4) impose on free-electron radiation? | It establishes a shape-independent upper limit on the spectral probabilities of energy loss and photon emission by free electrons in any photonic environment. | Definition | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | The upper limit demonstrated here is in the spontaneous emission regime for constant-velocity electrons, and can be extended to the stimulated regime by suitable reformulation. Stronger electron– photon interactions can change electron velocity by a non-negligible amount that alters the radiation. If necessary, t... | 1 | Yes | 0 |
Expert | What general limit does Equation (4) impose on free-electron radiation? | It establishes a shape-independent upper limit on the spectral probabilities of energy loss and photon emission by free electrons in any photonic environment. | Definition | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | In closing, we have theoretically derived and experimentally probed a universal upper limit to the energy loss and photon emission from free electrons. The limit depends crucially on the impact parameter $\\kappa _ { \\rho } d$ , but not on any other detail of the geometry. Hence, our limit applies even to the most com... | 1 | Yes | 0 |
Expert | What general limit does Equation (4) impose on free-electron radiation? | It establishes a shape-independent upper limit on the spectral probabilities of energy loss and photon emission by free electrons in any photonic environment. | Definition | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | The Smith–Purcell effect epitomizes the potential of free-electron radiation. Consider an electron at velocity $\\beta = \\nu / c$ traversing a structure with periodicity $a$ ; it generates far-field radiation at wavelength $\\lambda$ and polar angle $\\theta$ , dictated by2 $$ \\lambda = \\frac { a } { m } \\left( \... | augmentation | Yes | 0 |
Expert | What general limit does Equation (4) impose on free-electron radiation? | It establishes a shape-independent upper limit on the spectral probabilities of energy loss and photon emission by free electrons in any photonic environment. | Definition | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | We begin our analysis by considering an electron (charge $- e$ ) of constant velocity $\\nu \\hat { \\mathbf { x } }$ traversing a generic scatterer (plasmonic or dielectric, finite or extended) of arbitrary size and material composition, as in Fig. 1a. The free current density of the electron, ${ \\bf \\dot { J } } ( ... | augmentation | Yes | 0 |
Expert | What general limit does Equation (4) impose on free-electron radiation? | It establishes a shape-independent upper limit on the spectral probabilities of energy loss and photon emission by free electrons in any photonic environment. | Definition | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | $$ written in cylindrical coordinates $( x , \\rho , \\psi )$ ; here, $K _ { n }$ is the modified Bessel function of the second kind, $k _ { \\nu } = \\omega / \\nu$ and $k _ { \\rho } = \\sqrt { k _ { \\nu } ^ { 2 } - k ^ { 2 } } =$ k/βγ $\\scriptstyle ( k = \\omega / c$ , free-space wavevector; $\\gamma = 1 / \\sqr... | augmentation | Yes | 0 |
Expert | What general limit does Equation (4) impose on free-electron radiation? | It establishes a shape-independent upper limit on the spectral probabilities of energy loss and photon emission by free electrons in any photonic environment. | Definition | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | The grating limit (equation (6)) exhibits the same asymptotics as equations (5a) and (5b), thereby reinforcing the optimal-velocity predictions of Fig. 1c. The $( \\beta , k \\dot { d } )$ dependence of $\\mathcal { G }$ (see Fig. 2a) shows that slow (fast) electrons maximize Smith–Purcell radiation in the small (lar... | augmentation | Yes | 0 |
Expert | What general limit does Equation (4) impose on free-electron radiation? | It establishes a shape-independent upper limit on the spectral probabilities of energy loss and photon emission by free electrons in any photonic environment. | Definition | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | To overcome this deficiency, we theoretically propose a new mechanism for enhanced Smith–Purcell radiation: coupling of electrons with $\\mathrm { B I C } s ^ { 1 3 }$ . The latter have the extreme quality factors of guided modes but are, crucially, embedded in the radiation continuum, guaranteeing any resulting Smit... | augmentation | Yes | 0 |
Expert | What general limit does Equation (4) impose on free-electron radiation? | It establishes a shape-independent upper limit on the spectral probabilities of energy loss and photon emission by free electrons in any photonic environment. | Definition | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | Author contributions Y.Y., O.D.M., I.K. and M.S. conceived the project. Y.Y. developed the analytical models and numerical calculations. A.M. prepared the sample under study. Y.Y., A.M., C.R.-C., S.E.K. and I.K. performed the experiment. Y.Y., T.C. and O.D.M. analysed the asymptotics and bulk loss of the limit. S.G.J.,... | augmentation | Yes | 0 |
Expert | What general limit does Equation (4) impose on free-electron radiation? | It establishes a shape-independent upper limit on the spectral probabilities of energy loss and photon emission by free electrons in any photonic environment. | Definition | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | g ( \\mathbf { k } ) \\triangleq \\int f ( \\mathbf { r } ) \\mathrm { e } ^ { - i \\mathbf { k } \\cdot \\mathbf { r } } \\mathrm { d } \\mathbf { r } , g ( \\mathbf { r } ) \\triangleq \\frac { 1 } { \\left( 2 \\pi \\right) ^ { 3 } } \\int g ( \\mathbf { k } ) \\mathrm { e } ^ { i \\mathbf { k } \\cdot \\mathbf { r }... | augmentation | Yes | 0 |
Expert | What general limit does Equation (4) impose on free-electron radiation? | It establishes a shape-independent upper limit on the spectral probabilities of energy loss and photon emission by free electrons in any photonic environment. | Definition | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | free-space optical elements, enabling simultaneous measurement of the spectrum and of the spatial radiation pattern. The SEM used for the experiment was a JEOL JSM-6010LA. Its energy spread at the gun exit was in the range 1.5 to $2 . 5 \\mathrm { e V }$ for the range of acceleration voltages considered in this paper. ... | augmentation | Yes | 0 |
IPAC | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | INTRODUCTION Synchrotron radiation (SR) sources based on electron storage rings are among the primary tools in materials research, physics, chemistry, and biology to study the structure of matter on the atomic scale [1]. However, phase transitions, chemical reactions as well as changes of molecular conformation, electr... | augmentation | NO | 0 |
IPAC | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | Workshop on Beam Diagnostics and Dynamics in Ultra-Low Emittance Rings In the future, synchrotron radiation sources and $\\mathrm { e + / e - }$ colliders will require high-quality beams with ultra-low emittance. To assess the beam quality and stability, technological breakthroughs in beam diagnostics are necessary to ... | augmentation | NO | 0 |
IPAC | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | The assembly consists of a cylindrical vacuum tank housing the instrument with a motor driving a protruding hollow shaft onto which are mounted two titanium forks which support a carbon fibre ‘wire’ of $3 4 \\mu \\mathrm { m }$ diameter (see Fig. 1). The wire is rotated 270 degrees at high speed, crossing the beam ... | augmentation | NO | 0 |
IPAC | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | File Name:EXPERIMENTAL_DESIGNS_OF_COHERENT_SYNCHROTRON.pdf EXPERIMENTAL DESIGNS OF COHERENT SYNCHROTRONRADIATION IN COMPLEX BEAMS O. H. Ramachandran1,2‚àó , G. Ha1,2, C.-K. Huang3, X. Lu1,2, J. Power2, and Ji Qiang4 1Northern Illinois University, DeKalb, IL 60115, USA 2Argonne National Laboratory, Lemont, IL 60439, USA... | augmentation | NO | 0 |
IPAC | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | File Name:OPERATION_OF_THE_ESRF_-EBS_LIGHT_SOURCE.pdf OPERATION OF THE ESRF-EBS LIGHT SOURCE J. L. Revol, C. Benabderrahmane, P. Borowiec, E Buratin, N. Carmignani, L. Carver, A. D’Elia, M.Dubrulle, F. Ewald, A Franchi, G. Gautier, L. Hardy, L. Hoummi, J. Jacob, G. Le Bec, L. Jolly, I Leconte, S. M. Liuzzo, T. Perron... | augmentation | NO | 0 |
Expert | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | Table: Caption: Table 1 Nominal (no IDs) and measured parameter values at the observation point, together with derived emittances and emittance ratio Maximum error margins are linearly added when deducing the maximum emittance and emittance ratio errors. Body: <html><body><table><tr><td>Parameter</td><td>Nominal valu... | 2 | NO | 0 |
Expert | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | 4. Beam size measurements All measurements presented are performed with $\\pi$ -polarized vis–UV range SR in $3 5 0 / 4 0 0 \\mathrm { m A }$ multi-bunch top-up operation mode corresponding to $0 . 8 6 / 0 . 9 8 \\mathrm { n C }$ per bunch (390 out of 480 buckets populated). Most measurements were performed durin... | 1 | NO | 0 |
Expert | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | A one-dimensional profile of the intensity distribution through the two maxima, $I ( x _ { \\mathrm { m a x } } , y )$ , gives a distribution of the vertically polarized focused light that displays a dual peak separated by a zero minimum at the centre, $I ( x _ { \\mathrm { m a x } } , 0 ) = 0$ . A vertical beam size m... | 1 | NO | 0 |
Expert | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | The FWHM value is used for converting to $\\sigma _ { \\mathrm { e x } }$ . During measurements small beam ellipse rotations, originating either from betatron coupling or from a local vertical dispersion, are sometimes present. In this case, the vertically measured quantity is sey0 such that sey0osey, since only the ve... | 1 | NO | 0 |
Expert | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | $$ where $\\gamma = E / m _ { \\mathrm { e } } c ^ { 2 }$ , $E$ is the electron energy, $\\lambda$ is the observed radiation wavelength, $\\lambda _ { \\mathrm { c } } = 4 \\pi R / 3 \\gamma ^ { 3 }$ is the critical wavelength, $R$ is the radius of the electron trajectory, $p$ and $p ^ { \\prime }$ are the distances fr... | 2 | NO | 0 |
IPAC | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | File Name:DESIGN_OF_A_NON-INVASIVE_BUNCH_LENGTH_MONITOR_USING.pdf DESIGN OF A NON-INVASIVE BUNCH LENGTH MONITOR USING COHERENT SYNCHROTRON RADIATION SIMULATIONS C. Swain1,2,‚àó, J. Wolfenden1,2, L. Eley1,2, C. P. Welsch1,2 1Department of Physics, University of Liverpool, UK 2Cockcroft Institute, Warrington, UK Abst... | 4 | NO | 1 |
Expert | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | $$ since the dispersive contributions to the particle distribution are of course correlated horizontally and vertically. Since the vertical beam size, $\\sigma _ { \\mathrm { e y 0 } }$ , is obtained from integration over a narrow corridor (width $\\leqslant \\sigma _ { \\mathrm { e x } }$ , see Fig. 4) the correction ... | augmentation | NO | 0 |
Expert | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | Table 1 summarizes the emittance determinations. Measured values for the machine functions and for the rms beam sizes are presented. From the estimated maximum error in the measurement we give maximum error margins for the different quantities. The beam relative energy spread, $\\sigma _ { \\delta }$ , is the only quan... | augmentation | NO | 0 |
Expert | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | The branch used for the $\\pi$ -polarization method has a maximum clearance of $7 \\mathrm { { m r a d } _ { H } \\times 9 \\mathrm { { m r a d } _ { V } } }$ . The vis–UV light is twice directed through $9 0 ^ { \\circ }$ angles due to space constraints. This arrangement is also of benefit for optical reasons as a p... | augmentation | NO | 0 |
Expert | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | To explore further the model predictions we measured horizontal image profiles — retaining the setup for vertically polarized light — for different horizontal apertures set by the blocking blades at the lens position. Fig. 6 shows the results, where we have plotted measured and predicted FWHM/2.355 of the images, a... | augmentation | NO | 0 |
Expert | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | 6. Discussion So far we have tacitly assumed that the concept of horizontal and vertical emittance of a particle beam is valid. In the case of uncoupled motion, $\\mathit { \\varepsilon } _ { \\mathit { \\varepsilon } _ { x } }$ and $\\varepsilon _ { y }$ are defined as the two transverse rms phase space areas divided ... | augmentation | NO | 0 |
Expert | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | The emittances are deduced according to $$ \\varepsilon _ { x } = ( \\sigma _ { \\mathrm { e x } } ^ { 2 } - ( \\sigma _ { \\delta } \\eta _ { x } ) ^ { 2 } ) / \\beta _ { x } $$ and $$ \\varepsilon _ { y } = ( \\sigma _ { \\mathrm { e y 0 } } ^ { 2 } - ( \\sigma _ { \\delta } \\eta _ { y } ) ^ { 2 } ( 1 - ( \\sigma _ ... | augmentation | NO | 0 |
Expert | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | The sensitivity of the valley-to-peak intensity ratio at small vertical beam sizes can be slightly increased by either blocking a large part of the central SR or detecting at shorter wavelengths. Both methods bring the peaks of the FBSF closer together. We prefer the latter method, since it preserves the possibility to... | augmentation | NO | 0 |
Expert | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | The horizontal acceptance angle of the X-ray branch is 0.8 mrad. The water cooled pinhole array, fabricated from a $1 5 0 \\mu \\mathrm { m }$ thick tungsten sheet interspersed with $1 5 \\mu \\mathrm { m }$ diameter holes, is located $4 . 0 2 0 \\mathrm { m }$ from the source point. The light escaping these holes carr... | augmentation | NO | 0 |
Expert | What is SRW (Synchrotron Radiation Workshop)? | SRW (Synchrotron Radiation Workshop) is a wave optics simulation code used to model synchrotron radiation emission and propagation through optical systems. | Fact | Andersson_2008.pdf | A larger number of skew quads in the storage ring, would increase the risk of building up local coupling bumps when applying this straightforward, empirical method of minimization. Other methods, such as measurements of the fully coupled response matrix and the SVDbased minimization of the off-diagonal elements using a... | augmentation | NO | 0 |
IPAC | What is a stable closure phase? | A consistent phase sum around aperture triangles, indicating low noise and beam symmetry. | Fact | Carilli_2024.pdf | We can apply this reasoning to a particle in our system. We can compute integrals on the expression of the separatrices to evaluate the area of each region based on the value of $\\eta$ , and trace the evolution of the actions of the particles. We see that the process is di!erent if $| \\alpha | \\le 1$ or if $| { \\bo... | augmentation | NO | 0 |
IPAC | What is a stable closure phase? | A consistent phase sum around aperture triangles, indicating low noise and beam symmetry. | Fact | Carilli_2024.pdf | For each optics, we mainly look for the optimal Working Point (WP), i.e. the combination of horizontal and vertical tunes $( Q _ { x } , Q _ { y } )$ that yields the highest DA. It is however paramount to consider that, when doing a tune scan, a split — the difference between the fractional part of the horizontal and... | augmentation | NO | 0 |
IPAC | What is a stable closure phase? | A consistent phase sum around aperture triangles, indicating low noise and beam symmetry. | Fact | Carilli_2024.pdf | ION INSTABILITIES AT DIFFERENT STAGES WITH DIFFERENT FILLING PATTERNS Di!erent filling patterns have been studied and the chosen stable filling patterns are listed in Table. 2. The first two stages are considered early commissioning stages when vacuum conditions are not optimal and transverse multi-bunch feedback (TMBF... | augmentation | NO | 0 |
IPAC | What is a stable closure phase? | A consistent phase sum around aperture triangles, indicating low noise and beam symmetry. | Fact | Carilli_2024.pdf | $$ When $| p _ { \\theta } | < p _ { \\theta } ^ { \\mathrm { c r i t } }$ , the polynomial $\\mathcal { P } _ { 8 } ( r )$ has three positive roots: $$ 0 < r _ { * } ^ { \\mathrm { s t } } < r _ { * } ^ { \\mathrm { s e p } } < 1 < r _ { * } ^ { \\mathrm { u n } } . $$ Here, $r _ { * } ^ { \\mathrm { s e p } }$ corres... | augmentation | NO | 0 |
IPAC | What is a stable closure phase? | A consistent phase sum around aperture triangles, indicating low noise and beam symmetry. | Fact | Carilli_2024.pdf | Table: Caption: Table 1: Averaged Total Pressure at Di!erent Vacuum Condition Stages Body: <html><body><table><tr><td></td><td>Active NEG Coating</td><td>Saturated NEG Coating</td></tr><tr><td>Stage 1</td><td>0.9 nTorr</td><td>3.8 nTorr</td></tr><tr><td>Stage 2</td><td>0.5 nTorr</td><td>2.7 nTorr</td></tr><tr><td>Stag... | augmentation | NO | 0 |
IPAC | What is a stable closure phase? | A consistent phase sum around aperture triangles, indicating low noise and beam symmetry. | Fact | Carilli_2024.pdf | The transverse splitting of the MTE only works with a beam of low momentum spread. Consequently the RF voltage must be small $( V _ { \\mathrm { R F } } \\simeq 1 2 \\mathrm { k V }$ from one single cavity) during the about $1 5 0 ~ \\mathrm { m s }$ of the process. These are very unfavourable conditions for the evolut... | augmentation | NO | 0 |
IPAC | What is a stable closure phase? | A consistent phase sum around aperture triangles, indicating low noise and beam symmetry. | Fact | Carilli_2024.pdf | Table: Caption: Table 1: Stability Under Different P Values Body: <html><body><table><tr><td>Value of P</td><td>Critical ω</td><td>Stability (%)</td></tr><tr><td>0</td><td>3 kHz</td><td>-1.5-0.7</td></tr><tr><td>0.4</td><td>6 kHz</td><td>-0.8-0.5</td></tr><tr><td>0.8</td><td>10 kHz</td><td>-0.5-0.3</td></tr><tr><td>1... | augmentation | NO | 0 |
Expert | What is a stable closure phase? | A consistent phase sum around aperture triangles, indicating low noise and beam symmetry. | Fact | Carilli_2024.pdf | In radio interferometry, the voltages at each element are measured by phase coherent receivers and amplifiers, and visibilities are generated through subsequent cross correlation of these voltages using digital multipliers (Thomson, Moran, Swenson 2023; Taylor, Carilli, Perley 1999). In the case of optical aperture mas... | 4 | NO | 1 |
Expert | What is a stable closure phase? | A consistent phase sum around aperture triangles, indicating low noise and beam symmetry. | Fact | Carilli_2024.pdf | These images show the expected behaviour, with the diffraction pattern covering more of the CCD for the $3 \\mathrm { m m }$ hole image vs. the 5mm hole. Note that the total counts in the field is very large (millions of photons), and hence the Airy disk is visible beyond the first null, right to the edge of the field.... | 4 | NO | 1 |
Expert | What is a stable closure phase? | A consistent phase sum around aperture triangles, indicating low noise and beam symmetry. | Fact | Carilli_2024.pdf | File Name:Carilli_2024.pdf Deriving the size and shape of the ALBA electron beam with optical synchrotron radiation interferometry using aperture masks: technical choices Christopher L. Carilli∗ National Radio Astronomy Observatory, P. O. Box 0, Socorro, NM 87801, US Laura Torino† and Ubaldo Iriso‡ A... | 4 | NO | 1 |
Expert | What is a stable closure phase? | A consistent phase sum around aperture triangles, indicating low noise and beam symmetry. | Fact | Carilli_2024.pdf | Figure 13 also shows the closure phase for the 3-hole data, which has only one triad (holes 0-1-2). The 3-hole closure phase for triad 0-1-2 has a mean of $- 1 . 1 6 ^ { o }$ with an RMS of the time series of $0 . 2 7 ^ { o }$ . For comparison, the values for the 5-hole data for this triad were $- 2 . 1 7 ^ { o }$ and ... | 2 | NO | 0 |
IPAC | What is a stable closure phase? | A consistent phase sum around aperture triangles, indicating low noise and beam symmetry. | Fact | Carilli_2024.pdf | $$ \\begin{array} { c } { { J _ { x } ^ { 1 / 2 } = ( - 1 ) ^ { k + 1 } \\displaystyle \\frac { 3 | { \\cal G } | } { 4 \\alpha _ { x x } } ( 1 \\pm \\sqrt { 1 - \\displaystyle \\frac { 1 6 \\alpha _ { x x } \\delta } { 9 { \\cal G } ^ { 2 } } } ) , } } \\\\ { { \\phi _ { x } = \\displaystyle \\frac { k \\pi - \\phi _ ... | 1 | NO | 0 |
Expert | What is a stable closure phase? | A consistent phase sum around aperture triangles, indicating low noise and beam symmetry. | Fact | Carilli_2024.pdf | $$ V _ { a b } ( \\nu ) = \\int _ { \\mathrm { s o u r c e } } A _ { a b } ( \\hat { \\bf s } , \\nu ) I ( \\hat { \\bf s } , \\nu ) e ^ { - i 2 \\pi { \\bf u } _ { a b } \\cdot \\hat { \\bf s } } \\mathrm { d } \\Omega , $$ where, $a$ and $b$ denote a pair of array elements (eg. holes in a mask), $\\hat { \\pmb s }$ d... | augmentation | NO | 0 |
Expert | What is a stable closure phase? | A consistent phase sum around aperture triangles, indicating low noise and beam symmetry. | Fact | Carilli_2024.pdf | Masks were made with hole diameters of 3mm and 5mm, to investigate decoherence caused by possible phase fluctuations across a given hole. Observations were made with integration times (frame times) of 1 ms and 3 ms, to investigate decoherence by phase variations in time. Thirty frames are taken, each separated by 1 sec... | augmentation | NO | 0 |
Expert | What is a stable closure phase? | A consistent phase sum around aperture triangles, indicating low noise and beam symmetry. | Fact | Carilli_2024.pdf | IX. SUMMARY AND FUTURE DIRECTIONS A. Summary We have described processing and Fourier analysis of multi-hole interferometric imaging at optical wavelengths at the ALBA synchrotron light source to derive the size and shape of the electron beam using non-redundant masks of 2, 3, and 5 holes, plus a 6-hole mask with some ... | augmentation | NO | 0 |
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