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expert
What is the Robinson theorem?
The sum of the damping partition numbers equals 4.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
Calculate the damping times in the horizontal $( x )$ and vertical $( y )$ phase spaces, as well as in the energy/time phase space! I.10.7.22 Large Hadron Collider The Large Hadron Collider at CERN collides protons in a storage ring with $2 7 \\mathrm { k m }$ circumference. Assuming that synchrotron radiation is only ...
augmentation
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IPAC
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
We implemented the moments model [10] for calculation of QE for emission from semiconductors [7]. We extended the moments model to include light interference effects: $$ Q E = \\frac \\stackrel { \\infty } { \\bigcup } \\stackrel { \\bigcup } { \\int } \\stackrel { d E } { \\overbrace { E _ { g } + E _ { a } } } \\sta...
augmentation
NO
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IPAC
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
We implemented the moments model [4] for calculation of QE for emission from semiconductors [5]. We extended the moments model to include light interference e"ects: $$ Q E = A ( \\omega ) \\frac { \\int _ { E _ { a } } ^ { \\hbar \\omega - E _ { g } } d E E \\int _ { \\sqrt { \\frac { E _ { a } } { E } } } ^ { 1 } d u ...
augmentation
NO
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IPAC
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
$$ \\frac { d \\langle \\theta ^ { 2 } \\rangle } { d s } = \\int _ { \\theta _ { \\mathrm { m i n } } } ^ { \\theta _ { \\mathrm { m a x } } } \\theta ^ { 2 } \\frac { d \\sigma } { d \\Omega } \\frac { N _ { \\mathrm { A } } } { A } \\rho d \\Omega , $$ where $d \\Omega \\approx \\theta d \\theta d \\phi$ can be used...
augmentation
NO
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IPAC
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
Eq. (3) represent the electron motion equation, Poisson’s equation, and continuity equation respectively. For simplicity we assume the initial energy modulation is a cosine modulation, so the initial condition is $$ n ( z , 0 ) = n _ { 0 } , \\quad \\eta ( z , 0 ) = \\Delta \\eta \\cos ( k z ) . $$ where $k = 2 \\pi ...
augmentation
NO
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IPAC
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
The electron beam undergoes twice energy modulations in two undulators, and the laser wavenumbers are $k _ { 1 }$ and $k _ { 2 }$ , respectively. Only the dispersion parameter $R _ { 5 6 }$ is considered in dispersion (for the terahertz band, the collective effect of this process can be ignored). The energy modulation ...
augmentation
NO
0
IPAC
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
$$ where $Q _ { i }$ is dependent on the instantaneous momentum deviation $\\frac { \\Delta p _ { i } } { p _ { 0 } }$ , the nominal tune is denoted by $Q _ { 0 }$ , and $Q ^ { \\prime } , Q ^ { \\prime \\prime }$ are respectively first and second order chromaticities. We shall also assume that the momentum deviation i...
augmentation
NO
0
IPAC
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
$$ I ( \\Delta \\mathbf { x } ) = I _ { 0 } \\cdot \\left\\{ 1 + S ( \\theta ) \\cdot | \\mu ( \\Delta \\mathbf { x } ) | \\cdot \\cos \\left( \\frac { k } { 2 z } r ^ { 2 } \\right) \\right\\} , $$ where $\\Delta \\mathbf { x }$ denotes coordinates with respect to the center of the interference pattern, $r = | \\Delta...
augmentation
NO
0
IPAC
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
$$ \\frac { \\epsilon _ { x , I D s } } { \\epsilon _ { x } } = \\frac { 1 } { 1 + \\displaystyle \\frac { I _ { 2 , I D s } } { I _ { 2 , d i p . } } } $$ From Equation 1 we can also express the energy loss per turn as a function of $I _ { 2 , d i p }$ : $$ U _ { 0 } = P _ { 0 } / I \\approx \\frac { C _ { \\gamma } }...
augmentation
NO
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IPAC
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
INTRODUCTION Due to advancements in the Dielectric Laser Acceleration (DLA) technique [1], and in grating-based deflection structures [2], there is interest in an entirely grating-based compact particle accelerator. In order for this to become a reality, there are requirements for suitable diagnostics devices that are ...
1
NO
0
IPAC
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
The dispersion relation correspond to the free energy parabola with $m ^ { * } = m _ { e }$ . We suspect this dispersion relation arises due to the interaction of the emitted electron with the laser/plasmonic fields leading to momentum transfer in the presence of nanostructured surface non-uniformities at the center of...
1
NO
0
expert
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
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 , $$ The limits of equations (4), (5a) and (5b) are completely general; they set the maximum photon emission and energy loss of an electron beam coupled to an arbitrary photonic e...
1
NO
0
expert
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
Data availability. The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request.
augmentation
NO
0
expert
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
free-space optical elements, enabling simultaneous measurement of the spectrum and of the spatial radiation pattern. The SEM used for the experiment was a JEOL JSM-6010LA. Its energy spread at the gun exit was in the range 1.5 to $2 . 5 \\mathrm { e V }$ for the range of acceleration voltages considered in this paper. ...
augmentation
NO
0
expert
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
$$ 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
NO
0
expert
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
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...
augmentation
NO
0
expert
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
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
NO
0
expert
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
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
NO
0
expert
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
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
NO
0
expert
What is the Smith–Purcell effect equation relating wavelength λ to grating period a, electron velocity β, emission angle θ, and diffraction order m?
? = (a/m) (1/? - cos ?), where a is grating period, m is diffraction order, ? = v/c, and ? is emission angle.
Definition
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...
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NO
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expert
What is the bunch distribution at SHINE?
Two horn current profile
Summary
Beam_performance_of_the_SHINE_dechirper.pdf
This paper begins by reviewing the dechirper parameters for a small metallic pipe. The wakefield effects are studied with an ultra-short electron bunch in the Shanghai high repetition rate XFEL and extreme light facility (SHINE). Then, the process in dechirper is studied analytically and verified by numerical simulatio...
1
Yes
0
expert
What is the bunch distribution at SHINE?
Two horn current profile
Summary
Beam_performance_of_the_SHINE_dechirper.pdf
$$ \\epsilon _ { \\mathrm { f } } / \\epsilon _ { 0 } = ( \\langle \\gamma _ { \\mathrm { f } } \\rangle \\langle \\beta _ { \\mathrm { f } } \\rangle - \\langle \\alpha _ { \\mathrm { f } } \\rangle ^ { 2 } ) ^ { 1 / 2 } , $$ where the subscripts f o represent the final (original) situation. Then, the other plane is a...
1
Yes
0
expert
What is the bunch distribution at SHINE?
Two horn current profile
Summary
Beam_performance_of_the_SHINE_dechirper.pdf
$$ After calculating the inverse Fourier transformation, the distance s between the test and driving particles yields the longitudinal wake at the origin of $s = 0 ^ { + }$ , according to $w _ { \\mathrm { l } } \\sim e ^ { \\sqrt { s / s _ { 0 1 } } }$ . The relationship between the longitudinal point wake and the dis...
1
Yes
0
expert
What is the bunch distribution at SHINE?
Two horn current profile
Summary
Beam_performance_of_the_SHINE_dechirper.pdf
As described in Eq. (567), the distance factor is affected by the dechirper parameters, especially by the ratio $t / p$ . The wakefields induced by the Gaussian bunch with different $t /$ $p$ values are shown in Fig. 3. Over the initial $2 0 ~ { \\mu \\mathrm { m } }$ , all the induced wakefields have the same slope co...
2
Yes
0
expert
What is the bunch distribution at SHINE?
Two horn current profile
Summary
Beam_performance_of_the_SHINE_dechirper.pdf
The $\\beta$ functions for both models are plotted in Fig. 9. In [28], the emittance growth caused by the quadrupole wakefield is fully compensated only if $\\beta _ { x } = \\beta _ { y }$ . In practice, however, the beta functions always fluctuate, and the beam suffers from the residual quadrupole wakefield. For a pe...
1
Yes
0
expert
What is the bunch distribution at SHINE?
Two horn current profile
Summary
Beam_performance_of_the_SHINE_dechirper.pdf
$$ where $f ( q ) = n / d$ , and with $$ \\begin{array} { l } { n = q [ \\cosh [ q ( 2 a - y - y _ { 0 } ) ] - 2 \\cosh [ q ( y - y _ { 0 } ) ] } \\\\ { \\qquad + \\cosh [ q ( 2 a + y + y _ { 0 } ) ] ] } \\\\ { \\qquad - i k \\zeta [ \\sinh [ q ( 2 a - y - y _ { 0 } ) ] + \\sinh [ q ( 2 a + y + y _ { 0 } ) ] ] , } \\en...
augmentation
Yes
0
expert
What is the bunch distribution at SHINE?
Two horn current profile
Summary
Beam_performance_of_the_SHINE_dechirper.pdf
$$ \\begin{array} { l } { \\displaystyle { Z _ { \\mathrm { { r } } } ( k ) = \\frac { 4 i } { k c a ^ { 2 } } \\left[ 1 + \\frac { 1 + i } { \\sqrt { 2 k S _ { 0 \\mathrm { { r } } } } } \\right] ^ { - 1 } , } } \\\\ { \\displaystyle { Z _ { \\mathrm { { l } } } ( k ) = \\frac { 4 i } { k c a ^ { 2 } } \\left[ 1 + \\f...
augmentation
Yes
0
expert
What is the bunch distribution at SHINE?
Two horn current profile
Summary
Beam_performance_of_the_SHINE_dechirper.pdf
$$ Expanding the surface impedance $\\zeta ~ [ 1 8 ]$ in the first two orders, the short-range vertical dipole and quadrupole wakes near the axis are given by [19] $$ \\begin{array} { r l } & { w _ { y \\mathrm { d } } \\approx \\displaystyle \\frac { Z _ { 0 } \\mathrm { c } \\pi ^ { 3 } } { 6 4 a ^ { 4 } } { \\mathit...
augmentation
Yes
0
expert
What is the bunch distribution at SHINE?
Two horn current profile
Summary
Beam_performance_of_the_SHINE_dechirper.pdf
We next simply consider the quadrupole wake, where the beam is on-axis $( \\mathrm { y } _ { \\mathrm { c } } = 0 )$ . The transfer matrices for the focusing and defocusing quadrupole are given in Eq. (16), where $L$ is the length of the corrugated structure [25]. $$ \\begin{array} { r } { \\boldsymbol { R } _ { \\math...
augmentation
Yes
0
IPAC
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
INTRODUCTION Particle accelerators are among the grandest machines of the twentieth century because of their contributions to medicine, materials development, renewable energy, and the many fields of high-energy physics and life sciences, with roughly a third of all Nobel Prizes in physics being related to the use or a...
augmentation
NO
0
IPAC
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
The Livingston plot, shown in Figure 1, illustrates how the progress in achieving the energy frontier has been enabled by the history of invention in accelerator science and technology. One can clearly see that over several decades, there has been an exponential growth in the maximum attained energy. But the exponentia...
augmentation
NO
0
IPAC
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
A PLASMA TARGET FOR HIGH-EFFICIENCY ACCELERATION Using the same input bunch parameters and a half-metre plasma with $n _ { e } \\sim \\bar { 8 \\times 1 0 ^ { 1 5 } } \\mathrm { c m } ^ { - 3 }$ there is the prospect of achieving energy gains of at least $0 . 5 \\mathrm { G e V }$ . With this motivation, a discharge pl...
augmentation
NO
0
IPAC
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
THE AWAKE EXPERIMENT AWAKE is an R&D experiment at CERN with the aim to develop proton-driven based plasma wakefield acceleration. The wakefields are driven by highly-relativistic ${ \\mathrm { 4 0 0 G e V } }$ , relativistic factor $\\gamma _ { p + } \\sim 4 2 7 )$ and energetic $( > 1 9 \\mathrm { k J } )$ proton bun...
augmentation
NO
0
IPAC
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
File Name:ION-ION_COLLISIONS_IN_PLASMA_WAKEFIELD_ACCELERATORS.pdf ION-ION COLLISIONS IN PLASMA WAKEFIELD ACCELERATORS M.Yadav‚àó, K. Letko, J.B. Rosenzweig University of California, Los Angeles, California, USA Abstract The plasma wakefield accelerator, with acceleration gradients ranging from $\\mathrm { G e V / m }$ ...
augmentation
NO
0
IPAC
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
File Name:PROGRESS_TOWARDS_HIGH-QUALITY,_HIGH-REPETITION-RATE.pdf PROGRESS TOWARDS HIGH-QUALITY, HIGH-REPETITION-RATE PLASMA ACCELERATION AT FLASHForward J. C. Wood∗,1, L. Boulton1, J. Beinortaite˙1,2, J. Björklund Svensson1, G. Boyle1, J. Cowley3, A. Ferran Pousa1, B. Foster1,2, M. J. Garland1, P. González-Camina...
augmentation
NO
0
IPAC
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
INTRODUCTION To perform physics precision studies or discover physics beyond the Standard Model, high-energy colliders such as the existing Large Hadron Collider (LHC), the past Large Electron-Positron (LEP) or the Future Circular Collider (FCC) [1, 2] are desireable. However, limitations such as speed or radio-frequen...
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NO
0
IPAC
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
LASER-PLASMA ACCELERATOR Recent demonstrations of ${ \\sim } 1 \\mu \\mathrm { C }$ electron acceleration from kilo-joule laser OMEGA EP [2] and stable generation of ${ \\sim } 2 . 2 \\mathrm { p C }$ electron acceleration at $2 . 5 \\mathrm { H z }$ with $1 7 0 \\mathrm { m J }$ Ti-Sapphire laser [3] in the MeV range ...
augmentation
NO
0
IPAC
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
In order to gain better insight into the experimental results, we conducted 3D-PIC simulations using the OSIRIS code. We chose OSIRIS based on its ability to handle highly nonlinear and kinetic processes that occur during high-intensity particle and laser interactions with the plasma. As the relativistic beam propagate...
augmentation
NO
0
IPAC
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
File Name:AUTOMATED_EMITTANCEAND_ENERGYGAINOPTIMIZATIONFOR.pdf AUTOMATED EMITTANCE AND ENERGY GAIN OPTIMIZATION FOR PLASMA WAKEFIELD ACCELERATION M. Stobbe‚àó, R. Holtzapple Department of Physics, California Polytechnic State University, San Luis Obispo, CA, USA A. Knetsch, D. Storey SLAC National Accelerator Laborator...
augmentation
NO
0
IPAC
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
INTRODUCTION In recent years charged particle acceleration using solidstate nanostructured plasmas has attracted attention as a novel method of achieving ultra-high acceleration gradients, beam manipulation and gamma- or $\\mathrm { \\Delta X }$ -ray generation $[ 1 -$ 10]. In this context, PIC simulations have shown t...
1
NO
0
expert
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
The beam has geometric transverse emittances of $\\varepsilon _ { x } = 9 . 5 \\times 1 0 ^ { - 1 0 } \\mathrm { m }$ and $\\varepsilon _ { y } = 1 . 2 \\times 1 0 ^ { - 1 0 } \\mathrm { m }$ . It is focused with a quadrupole doublet to a spot with $1 0 \\mu \\mathrm { m }$ radius at the entrance of the plasma. With th...
4
NO
1
IPAC
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
It has been demonstrated that PWFA can be optimized with large datasets of accelerator measurements [3], which suggests that a search for an optimum could be automated [4]. At laser-driven plasma wakefield accelerators, Bayesian optimization was already applied successfully [5–7]. The objective of this work is to exa...
4
NO
1
expert
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
Recent plasma wakefield accelerator experiments have shown high-gradient acceleration of electrons using a 10-cm-long plasma11. To obtain energy gains of interest to high-energy physics, these high gradients must be extended over metre-scale plasmas. Such an extension transitions the plasma wakefield accelerator from a...
5
NO
1
expert
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
In a plasma wakefield accelerator large-amplitude electric fields result from space-charge waves excited by the passage of an ultrarelativistic electron beam through a plasma12. A fully ionized plasma can be formed in a neutral vapour when the radial electric field of the electron beam exceeds the field ionization thre...
augmentation
NO
0
expert
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
Thus, the full ionization extends over a radius of more than $1 0 0 \\mu \\mathrm { m }$ and ionization begins far earlier than the peak of the bunch current. Because the ionization region extends over a radius larger than the plasma collisionless skin depth $c / \\omega _ { \\mathrm { p } } ,$ where $\\omega _ { \\mat...
augmentation
NO
0
expert
What is the highest energy gain observed in a plasma wakefield accelerator?
44 GeV
Reasoning
Blumenfeld_et_al._-_2007_-_Energy_doubling_of_42_GeV_electrons_in_a_metre-scale_plasma_wakefield_accelerator.pdf
The images have been corrected at the level of a few per cent for the nonuniform collection efficiency of the optics. Pixel-to-pixel variations in the CCD offset and a common mode have been subtracted; the signal from X-rays that hit the CCD directly has been eliminated. Simulations. The simulations were done using the...
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What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
We perform quantitative experimental measurement of Smith– Purcell radiation to directly probe the upper limit. Figure 3a shows our experimental set-up (see Methods and Supplementary Section 7 for details). A one-dimensional (1D) $5 0 \\%$ -filling-factor grating (Au-covered single-crystalline Si)—the quint...
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What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
Definition
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 ...
1
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expert
What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
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. ...
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expert
What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
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
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expert
What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
Definition
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...
4
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1
expert
What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
Definition
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...
4
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1
expert
What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
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...
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What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
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 $$ \\lambda = \\frac { a } { m } \\left( \...
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What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
We begin our analysis by considering an electron (charge $- e$ ) of constant velocity $\\nu \\hat { \\mathbf { x } }$ traversing a generic scatterer (plasmonic or dielectric, finite or extended) of arbitrary size and material composition, as in Fig. 1a. The free current density of the electron, ${ \\bf \\dot { J } } ( ...
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What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
Definition
Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf
$$ 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...
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What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
Definition
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...
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What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
Definition
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...
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What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
Definition
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...
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What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
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...
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What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
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...
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What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
Definition
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...
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What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
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.,...
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What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
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 }...
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What is the impact parameter κρd, and why is it pivotal in determining maximal radiation?
??d = kd/(??), representing the normalized electron–structure separation; it dictates whether fast or slow electrons maximize radiation in far- or near-field regimes.
Definition
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.
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What is the inverse design approach employed for optimizing the radiator structure?
A gradient-based photonic inverse design using the Adam optimizer to tailor dielectric distributions within unit cells under symmetry constraints to maximize radiation power.
Definition
hermann-et-al-2022-inverse-designed-narrowband-thz-radiator-for-ultrarelativistic-electrons.pdf
Michelson Interferometer and THz Detector. For the spectrum measurements, we installed a Michelson interferometer outside the vacuum chamber. The THz pulse was first sent through an in-vacuum lens made of PMMA with a diameter of $2 5 \\ \\mathrm { m m }$ and a focal length of $1 0 0 ~ \\mathrm { { m m } }$ . The lens c...
1
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What is the inverse design approach employed for optimizing the radiator structure?
A gradient-based photonic inverse design using the Adam optimizer to tailor dielectric distributions within unit cells under symmetry constraints to maximize radiation power.
Definition
hermann-et-al-2022-inverse-designed-narrowband-thz-radiator-for-ultrarelativistic-electrons.pdf
ACS PHOTONICS READ Quasi-BIC Modes in All-Dielectric Slotted Nanoantennas for Enhanced $\\mathbf { E r ^ { 3 + } }$ Emission Boris Kalinic, Giovanni Mattei, et al.JANUARY 18, 2023 ACS PHOTONICS READ Get More Suggestions >
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What is the inverse design approach employed for optimizing the radiator structure?
A gradient-based photonic inverse design using the Adam optimizer to tailor dielectric distributions within unit cells under symmetry constraints to maximize radiation power.
Definition
hermann-et-al-2022-inverse-designed-narrowband-thz-radiator-for-ultrarelativistic-electrons.pdf
A typical autocorrelation measurement for a charge of 9.4 pC is depicted in Figure 2b. The shape of the autocorrelation is not perfectly symmetric in amplitude and stage position. The amplitude asymmetry could be a result of a nonlinear detector response (onset of saturation). This is in agreement with the slight devia...
1
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Expert
What is the inverse design approach employed for optimizing the radiator structure?
A gradient-based photonic inverse design using the Adam optimizer to tailor dielectric distributions within unit cells under symmetry constraints to maximize radiation power.
Definition
hermann-et-al-2022-inverse-designed-narrowband-thz-radiator-for-ultrarelativistic-electrons.pdf
The objective function $G$ , quantifying the performance of a design $\\phi ,$ is given by the line integral of the Poynting vector $\\begin{array} { r } { { \\bf S } ( x , y ) = \\mathrm { R e } \\left\\{ \\frac { 1 } { 2 } { \\bf E } \\times { \\bf H } ^ { * } \\right\\} } \\end{array}$ in the $x$ -direction along th...
4
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1
Expert
What is the inverse design approach employed for optimizing the radiator structure?
A gradient-based photonic inverse design using the Adam optimizer to tailor dielectric distributions within unit cells under symmetry constraints to maximize radiation power.
Definition
hermann-et-al-2022-inverse-designed-narrowband-thz-radiator-for-ultrarelativistic-electrons.pdf
An in-vacuum PMMA lens with a diameter of $2 5 \\mathrm { ~ m m }$ collimated parts of the emitted radiation. A Michelson interferometer was used to measure the first-order autocorrelation of the electromagnetic pulse and to obtain its power spectrum via Fourier transform (Figure 2b and Methods). The measured spectrum ...
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What is the inverse design approach employed for optimizing the radiator structure?
A gradient-based photonic inverse design using the Adam optimizer to tailor dielectric distributions within unit cells under symmetry constraints to maximize radiation power.
Definition
hermann-et-al-2022-inverse-designed-narrowband-thz-radiator-for-ultrarelativistic-electrons.pdf
We drove the structure with electron bunches with a duration of approximately 30 fs (RMS), which is much shorter than the resonant wavelength corresponding to a period of 3 ps. Hence, we expect to see the coherent addition of radiated fields. To experimentally verify this, we varied the bunch charge. Figure 4 shows the...
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What is the inverse design approach employed for optimizing the radiator structure?
A gradient-based photonic inverse design using the Adam optimizer to tailor dielectric distributions within unit cells under symmetry constraints to maximize radiation power.
Definition
hermann-et-al-2022-inverse-designed-narrowband-thz-radiator-for-ultrarelativistic-electrons.pdf
During and after our experiments, the structure did not show any signs of performance degradation or visible damage. It was used continuously for eight hours with a bunch charge of approximately $1 0 ~ \\mathrm { p C }$ at a pulse repetition rate of $1 \\ \\mathrm { H z }$ . CONCLUSION The here-presented beam-synchrono...
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What is the inverse design approach employed for optimizing the radiator structure?
A gradient-based photonic inverse design using the Adam optimizer to tailor dielectric distributions within unit cells under symmetry constraints to maximize radiation power.
Definition
hermann-et-al-2022-inverse-designed-narrowband-thz-radiator-for-ultrarelativistic-electrons.pdf
The second difficulty arises from the long-range evanescent waves of ultrarelativistic electrons. The spectral density of the electric field of a line charge decays with $\\bar { \\exp ( - \\kappa | x | ) }$ , where $\\kappa =$ $2 \\pi / \\beta \\gamma \\lambda$ , with $\\beta \\approx 1$ and $\\gamma \\approx 6 0 0 0$...
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What is the inverse design approach employed for optimizing the radiator structure?
A gradient-based photonic inverse design using the Adam optimizer to tailor dielectric distributions within unit cells under symmetry constraints to maximize radiation power.
Definition
hermann-et-al-2022-inverse-designed-narrowband-thz-radiator-for-ultrarelativistic-electrons.pdf
Simulations. The 3D frequency-domain simulation was performed in COMSOL, based on the finite element method. The simulation cell, as shown in the lower right inset of Figure 1c, consists of a single unit cell of the grating, with a height of 4 mm and periodic boundaries along the electron propagation direction. An opti...
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What is the inverse design approach employed for optimizing the radiator structure?
A gradient-based photonic inverse design using the Adam optimizer to tailor dielectric distributions within unit cells under symmetry constraints to maximize radiation power.
Definition
hermann-et-al-2022-inverse-designed-narrowband-thz-radiator-for-ultrarelativistic-electrons.pdf
Accelerator Setup. The experiments used $1 0 ~ \\mathrm { p C }$ electron bunches from the $3 . 2 \\mathrm { G e V }$ Athos beamline of SwissFEL27 operated at a pulse repetition rate of $1 \\ \\mathrm { H z }$ to keep particle losses during alignment at a tolerable level. The standard bunch charge at SwissFEL is $2 0 0...
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What is the inverse design approach employed for optimizing the radiator structure?
A gradient-based photonic inverse design using the Adam optimizer to tailor dielectric distributions within unit cells under symmetry constraints to maximize radiation power.
Definition
hermann-et-al-2022-inverse-designed-narrowband-thz-radiator-for-ultrarelativistic-electrons.pdf
A bunch length of 30 fs (RMS) was measured for similar machine settings in a separate shift with a transverse deflecting cavity (TDC) in the Aramis beamline of the accelerator. Therefore, we expect the longitudinal dimension of the electron beam at the ACHIP chamber to be on the order of $1 0 \\ \\mu \\mathrm m ,$ , al...
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What is the inverse design approach employed for optimizing the radiator structure?
A gradient-based photonic inverse design using the Adam optimizer to tailor dielectric distributions within unit cells under symmetry constraints to maximize radiation power.
Definition
hermann-et-al-2022-inverse-designed-narrowband-thz-radiator-for-ultrarelativistic-electrons.pdf
The geometric acceptance angle of the Michelson interferometer $\\Delta \\theta$ in the plane of the electron beam and the THz radiation defines the accepted bandwidth of the setup. According to the Smith‚àíPurcell relation (eq 1), it is given by $$ \\Delta \\lambda = a \\sin \\theta \\Delta \\theta $$ Around the ortho...
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What is the main goal of the UA9 experiment?
Demonstrate the feasibility of a crystal-based collimation for high-energy hadron machines.
Fact
CpFM_paper.pdf
In Fig. 7 the angular scan of the UA9 crystal-1 during a proton run is shown. It is displayed both by the BLMs and the CpFM (CpFM position is such that both the bars intercept the whole channeled beam when the crystal is in the optimal channeling position). The first and the last angular regions (angle $< - 2 7 0 0$ Œ...
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expert
What is the main goal of the UA9 experiment?
Demonstrate the feasibility of a crystal-based collimation for high-energy hadron machines.
Fact
CpFM_paper.pdf
In order to fully characterize this collimation system, it is essential to steadily monitor the flux of the halo particles deflected by the crystal towards the absorber. Typical crystal-extracted fluxes range from $1 0 ^ { 5 }$ up to $1 0 ^ { 7 }$ protons/s (i.e. from 1 up to 200 protons per SPS revolution) and about $...
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expert
What is the main goal of the UA9 experiment?
Demonstrate the feasibility of a crystal-based collimation for high-energy hadron machines.
Fact
CpFM_paper.pdf
Finally, particular attention has to be paid to the shape of the distributions in Fig. 9(b). They are not Gaussian. For such a high fluxes, this cannot depend on the detector resolution, at least for the CpFM 2 channel which has the better efficiency. This can be demonstrated deriving the CpFM 2 resolution for an incid...
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What is the main goal of the UA9 experiment?
Demonstrate the feasibility of a crystal-based collimation for high-energy hadron machines.
Fact
CpFM_paper.pdf
File Name:CpFM_paper.pdf Commissioning and operation of the Cherenkov detector for proton Flux Measurement of the UA9 experiment F.M. Addesa a,‚àó, D. Breton d, L. Burmistrov d, G. Cavoto a,b, V. Chaumat d, S. Dubos d, L. Esposito c, F. Galluccio e, M. Garattini c,g, F. Iacoangeli a, J. Maalmi d, D. Mirarchi c, S. ...
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expert
What is the main goal of the UA9 experiment?
Demonstrate the feasibility of a crystal-based collimation for high-energy hadron machines.
Fact
CpFM_paper.pdf
1. Introduction The primary goal of the UA9 experiment [1] is to demonstrate the feasibility of a crystal-based halo collimation as a promising and better alternative to the standard multi-stage collimation system for high-energy hadron machines. The main installation of the experiment is located in the Long Straight S...
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1
expert
What is the main goal of the UA9 experiment?
Demonstrate the feasibility of a crystal-based collimation for high-energy hadron machines.
Fact
CpFM_paper.pdf
beam profile monitors) Cherenkov detectors In-vacuum detectors High-energy particle accelerators A B S T R A C T The UA9 Experiment at CERN-SPS investigates channeling processes in bent silicon crystals with the aim to manipulate hadron beams. Monitoring and characterization of channeled beams in the high energy accele...
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IPAC
What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
At the state art of laser-optical technologies, it is possible to create an optical resonator with a power incident on mirrors not exceeding several tens of $\\mathrm { k W }$ . Under these conditions the scattered photons beam intensity will not exceed of about 1012 phot/s. Considering this circumstance, it would be e...
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IPAC
What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
File Name:A_NOVEL_METHOD_TO_SUPPRESS_THE_EMITTANCE_VARIATION_IN.pdf A NOVEL METHOD TO SUPPRESS THE EMITTANCE VARIATION IN EXTREMELY LOW EMITTANCE LIGHT SOURCE STORAGE RINGS\\* K. Soutome†1, T. Hiraiwa, H. Tanaka, RIKEN SPring-8 Center, Sayo, Japan 1also at JASRI, Sayo, Japan Abstract We propose a novel method to supp...
4
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expert
What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
$$ Figure I.10.2 shows the development of the peak brilliance of $\\mathrm { \\Delta X }$ -ray sources during the last century. Scientists working in synchrotron radiation facilities have gotten accustomed to an extremely high flux, as well as an excellent stability of their X-ray source. The flux is controlled on the ...
4
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1
expert
What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
I.10.3.5 Some observations I.10.3.5.1 Dependence of damping times on particle energy and type As you can see in Equation I.10.9, the radiation power emitted by a charged particle circulating in a storage ring is inversely proportional to the fourth power of its mass, for a given energy. This fundamental relationship ha...
4
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1
expert
What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
The term diffraction-limited refers to a system, typically in optics or imaging, where the resolution or image detail is primarily restricted by the fundamental diffraction of light rather than by imperfections or aberrations in the source, or in imaging components. In such a system, the performance reaches the theoret...
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What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
File Name:Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation.pdf Chapter I.10 Synchrotron radiation Rasmus Ischebeck Paul Scherrer Institut, Villigen, Switzerland Electrons circulating in a storage ring emit synchrotron radiation. The spectrum of this powerful radiation spans from the far infrared to the $\\boldsymbol {...
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What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
How would you measure this radiation? I.10.7.27 Superconducting undulators What is the advantage of using undulators made with superconducting coils, in comparison to permanentmagnet arrays? What are drawbacks? I.10.7.28 In-vacuum undulators What are the advantages of using in-vacuum undulators? What are possible diffi...
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What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
$$ respectively. The solution to Maxwell’s equations for this time-varying charge and current density can be found by using the wave equation for the electromagnetic potentials. In the Lorentz gauge, this wave equation reads $$ \\vec { \\nabla } ^ { 2 } \\Phi - \\frac { 1 } { c ^ { 2 } } \\frac { \\partial ^ { 2 } \\...
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What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
I.10.7.55 Practical applications of synchrotron radiation The Italian Light Source Elettra is a 3rd generation synchrotron source with $2 5 9 \\mathrm { m }$ circumference, and can operate at beam energies of either $2 . 0 \\mathrm { G e V }$ or $2 . 4 \\mathrm { G e V } ,$ with beam currents of $3 1 0 \\mathrm { m A }...
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What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
$$ Computing the photon flux $\\dot { N } _ { \\gamma }$ for an undulator is even more elaborate than the calculation for a single dipole, and we just cite the result [2] $$ { \\dot { N } } _ { \\gamma } = 1 . 4 3 \\cdot 1 0 ^ { 1 4 } N I _ { b } Q _ { n } ( K ) , $$ where $$ Q _ { n } ( K ) = \\frac { 1 + K ^ { 2 } / ...
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What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
$$ The difference to Equation I.10.13 is small for $k _ { u } y \\ll 1$ and will be neglected in the following. Helical undulators have a magnetic field on the axis $$ \\begin{array} { r } { \\vec { B } ( z ) = \\vec { u } _ { x } B _ { 0 } \\cos ( k _ { u } z ) - \\vec { u } _ { y } B _ { 0 } \\sin ( k _ { u } z ) . }...
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expert
What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
$$ which is Bragg’s law. Note that contrary to the diffraction on a two-dimensional surface, which is often considered fir visible light, $\\mathrm { \\Delta } \\mathrm { X }$ -rays diffract on a three-dimensional crystal lattice. In this case, not only the exit angle matters, but also the incoming angle must fulfill...
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expert
What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
I.10.7.16 Critical energy For the electron beam of the previous exercise, calculate the critical photon energy $\\varepsilon _ { c }$ that is emitted by the superbends with $B = 6 \\mathrm { \\ : T }$ and draw a sketch of the radiation spectrum. What is the useful photon energy range for experiments, assuming that the ...
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What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
$$ where a dimensionless undulator parameter has been introduced, $$ K = \\frac { e B _ { 0 } } { m _ { e } c k _ { u } } . $$ The electron follows a sinusoidal trajectory $$ x ( z ) = - \\frac { K } { k _ { u } \\gamma \\beta _ { z } } \\sin ( k _ { u } z ) . $$ Synchrotron radiation is emitted by relativistic electro...
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expert
What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
– Auger electrons: similarly to fluorescence, this effect starts with the ionization or excitation of an inner-shell electron due to the interaction with the X-ray photon. This leaves a vacancy in the inner shell, which is then filled with an outer-shell electron. However, instead of releasing the excess energy as a ...
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expert
What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
$$ \\vec { B } ( 0 , 0 , z ) = \\vec { u } _ { y } B _ { 0 } \\sin ( k _ { u } z ) , $$ where $k _ { u } = 2 \\pi / \\lambda _ { u }$ with $\\lambda _ { u }$ the period of the magnetic field, $B _ { 0 }$ is the maximum field and $\\vec { u } _ { y }$ is the unit vector in $y$ direction. Due to the Maxwell equations, th...
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expert
What is the natural emittance in a storage ring?
It is the equilibrium emittance where damping and quantum excitation balance out.
Definition
Ischebeck_-_2024_-_I.10_—_Synchrotron_radiation
$$ and $$ \\vec { A } ( \\vec { x } , t ) = \\frac { 1 } { 4 \\pi \\varepsilon _ { 0 } C ^ { 2 } } \\int d ^ { 3 } \\vec { x } ^ { \\prime } \\int d t ^ { \\prime } \\frac { \\vec { j } ( \\vec { x } ^ { \\prime } , t ) } { | \\vec { x } - \\vec { x } ^ { \\prime } | } \\delta \\left( t ^ { \\prime } + \\frac { \\vec {...
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