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 |
|---|---|---|---|---|---|---|---|---|
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | In fact, with a full control over amplitude and phase seen by the particles the question becomes how to best optimize the drive pulse. At this purpose, it is envisioned adopting machine learning algorithms to optimize the 2D mask which gets applied to the laser drive pulse by the liquid crystal modulator [48]. 5 DLA Un... | 4 | Yes | 1 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | Looking towards applications of dielectric laser acceleration, electron diffraction and the generation of light with particular properties are the most catching items, besides the omnipresent goal of creating a TeV collider for elementary particle physics. As such we will look into DLA-type laser driven undulators, whi... | 4 | Yes | 1 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | 4.2 Soft tuning of DLA parameters 11 5 DLA Undulator 13 5.1 Tilted Grating Design 13 5.2 Analytical Model for the Non-Synchronous Undulator 14 5.3 Simulation of the Beam Dynamics in Tilted Gratings 16 6 Conclusion 18 1 Introduction The combination of periodic dielectric structures and coherent light allows to reverse t... | 1 | Yes | 0 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | There have been two major approaches to producing injectors of sufficiently high brightness. The first approach uses a nanotip cold field or Schottky emitter in an electron microscope column that has been modified for laser access to the cathode [14, 21, 22]. One can then leverage the decades of development that have b... | 5 | Yes | 1 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | $$ where $m _ { 0 } c ^ { 2 } / q = 5 1 1 \\mathrm { \\ k V }$ is the rest energy equivalent and $\\phi$ is the phase within one DLA cell. Analyzing the solutions of the equation for transverse motion into a slowly varying secular component and a fast oscillation, we can rewrite for the slow drift motion $$ { \\frac { ... | 1 | Yes | 0 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | 2 Ultra-low Emittance Injector The sub- $4 0 0 \\\\mathrm { n m }$ wide accelerator channel and field non-uniformity in dielectric laser accelerators place very strict emittance requirements on the electron injector. Typical acceptances in an APF DLA designed for a 2 micron drive laser require a ${ \\\\sim } 1 0 ~ \\\\... | 5 | Yes | 1 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | Key to the high gradients in DLA is the synchronization of optical near fields to relativistic electrons, expressed by the Wideroe condition $$ \\lambda _ { g } = m \\beta \\lambda $$ where $\\lambda _ { g }$ is the grating period, $\\lambda$ is the laser wavelength, and $\\beta = \\nu / c$ is the the electron velocity... | augmentation | Yes | 0 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | $$ \\lambda _ { \\mathrm { { p } } } = \\frac { \\lambda _ { \\mathrm { { u } } } } { 2 { \\gamma _ { 0 } } ^ { 2 } } \\left( 1 + \\frac { { K _ { \\mathrm { { z } } } } ^ { 2 } } { 2 } \\right) \\approx 9 ~ \\mathrm { { n m } , } $$ corresponding to soft $\\boldsymbol { \\mathrm { X } }$ -rays with $E _ { \\mathrm { p... | augmentation | Yes | 0 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | 4.2 Soft tuning of DLA parameters The original plan proposed to hard-wire spatial harmonics into the structure to obtain the ponderomotive focusing effect. In practice, one can also simply modulate the drive laser phase, effectively introducing spatial harmonics into a generic, strictly periodic grating, see Fig. 8. Th... | augmentation | Yes | 0 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | $$ where $E _ { z }$ is the longitudinal component of the electric field at the laser center frequency in the channel. Often, $E _ { z }$ is normalized to the amplitude of the incident laser field. The transverse dependence of $\\boldsymbol { e } _ { 1 }$ allows also to calculate the the transverse kicks by means of th... | augmentation | Yes | 0 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | $$ The first term recovers the tracking equation of DLATrack6D (see ref. [9]). The correction terms contribute less than $1 \\%$ for the investigated structures. Figure 14 a) compares tracking results for the particle at the beam center of a synchronous and a non-synchronous DLA undulator. In the synchronous undulator ... | augmentation | Yes | 0 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | k _ { x } ^ { 2 } + k _ { y } ^ { 2 } = - \\frac { \\omega ^ { 2 } } { \\beta ^ { 2 } \\gamma ^ { 2 } c ^ { 2 } } , $$ where $\\omega = 2 \\pi c / \\lambda$ is the laser angular frequency and $\\beta , \\gamma$ are the relativistic velocity and mass factors. Note that the longitudinal field Eq. 3.1 suffices to describe... | augmentation | Yes | 0 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | $$ \\\\mathbf { a } \\\\left( x , y , z , c t \\\\right) = a _ { \\\\mathrm { z } } \\\\cosh \\\\left( k _ { \\\\mathrm { y } } y \\\\right) \\\\sin \\\\left( k c t - k _ { \\\\mathrm { z } } z + k _ { \\\\mathrm { x } } x \\\\right) \\\\mathbf { e } _ { \\\\mathrm { z } } $$ with the reciprocal grating vectors of the ... | augmentation | Yes | 0 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | $$ k _ { \\mathrm { u } } \\approx \\frac { 1 } { \\beta } k - k _ { \\mathrm { z } } . $$ The analytical model provides design guidelines for the experimental realization of an DLA undulator. In Eq. (5.4) the deviation of $k$ with respect to a synchronous DLA structure determines the undulator wavelength $\\lambda _ {... | augmentation | Yes | 0 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | Moving forward, there are possibilities of increasing the acceleration gradients in DC biased electron sources through the use of novel electrode materials and preparation [25, 27] to 20 to 70 $\\mathbf { k V / m m }$ or greater gradients. These higher gradients, combined with the local field enhancement at a nanotip e... | augmentation | Yes | 0 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | 3 Alternating Phase Focusing DLA 3.1 Principle and Nanophotonic Structures The advantage of high gradient in DLA comes with the drawback of non-uniform driving optical nearfields across the beam channel. The electron beam, which usually fills the entire channel, is therefore defocused. The defocusing is resonant, i.e. ... | augmentation | Yes | 0 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | Logan Su, Rahul Trivedi, Yu Miao, Olav Solgaard, Robert L Byer, and Jelena Vuckovic. On-chip integrated laser-driven particle accelerator. Science, 367(January):79–83, 2020. [46] D. Cesar, J. Maxson, P. Musumeci, X. Shen, R. J. England, and K. P. Wootton. Optical design for increased interaction length in a high grad... | augmentation | Yes | 0 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | $$ K _ { \\mathrm { z } } = a _ { \\mathrm { z } } { \\frac { k _ { \\mathrm { x } } } { k _ { \\mathrm { u } } } } = { \\frac { q } { m _ { 0 } c ^ { 2 } } } { \\frac { k _ { \\mathrm { z } } } { k k _ { \\mathrm { u } } } } \\left| e _ { 1 } \\left( \\alpha \\right) \\right| \\tan \\alpha \\ . $$ Figure $1 3 \\mathrm... | augmentation | Yes | 0 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | Different types of DLA structures (single cells) are described in Fig. 2 for low energy (subrelativistic) and in Fig. 6 for high energy (relativistic). The usual materials are silicon or fused silica $( \\\\mathrm { S i O } _ { 2 } )$ , which can be nanofabricated by established techniques from the semiconductor indust... | augmentation | Yes | 0 |
expert | According to the beam requirements for a typical DLA, is an electron source with 5 mm emittance suitable? | No, the aperture is sub-400nm | reasoning | Beam_Dynamics_in_Dielectric_Laser_Acceleration.pdf | 6 Conclusion For the study of beam dynamics in DLA, computer simulations will remain essential. With combined numerical and experimental approaches, the challenges of higher initial brightness and brightness preservation along the beamline can be tackled. The electron sources available from electron microscopy technolo... | augmentation | Yes | 0 |
Expert | At what signal voltage is the gas detector pulse energy signal no longer in the linear range? | If the peak of the signal is higher than about 0.8 Volts. | Fact | [FELFastPulseEnergy]_JSR_30(2023).pdf | Another component of the gas detector system developed by DESY and used at various facilities, including SwissFEL, is the huge aperture open multiplier (HAMP), which is a large multiplier used for single-shot relative flux measurements that are not an absolute evaluation of the pulse energy. The response of this device... | 2 | Yes | 0 |
Expert | At what signal voltage is the gas detector pulse energy signal no longer in the linear range? | If the peak of the signal is higher than about 0.8 Volts. | Fact | [FELFastPulseEnergy]_JSR_30(2023).pdf | The HAMPs, in contrast, need characterization to evaluate their range of linearity under an applied gain voltage. This voltage needs to be regulated through an overwatch program so that the HAMP detector signals remain linear, while also being high enough to provide a good signal-to-noise ratio on its analog-to-digital... | 5 | Yes | 1 |
Expert | At what signal voltage is the gas detector pulse energy signal no longer in the linear range? | If the peak of the signal is higher than about 0.8 Volts. | Fact | [FELFastPulseEnergy]_JSR_30(2023).pdf | File Name:[FELFastPulseEnergy]_JSR_30(2023).pdf Online absolute calibration of fast FEL pulse energy measurements Received 29 November 2022 Accepted 7 February 2023 Edited by Y. Amemiya, University of Tokyo, Japan Keywords: free-electron lasers; FELs; shot-to-shot absolute flux measurements. Pavle Juranic´,\\* Arturo ... | 4 | Yes | 1 |
Expert | At what signal voltage is the gas detector pulse energy signal no longer in the linear range? | If the peak of the signal is higher than about 0.8 Volts. | Fact | [FELFastPulseEnergy]_JSR_30(2023).pdf | If the repetition rate of the FEL changes, the rolling buffer size is recalculated to accommodate the larger number of points in the chosen time period, and the buffer itself is reset. However, the constant $C$ remains unchanged unless the photon energy or the HAMP gain voltage change. The data buffer and single-shot p... | 2 | Yes | 0 |
Expert | At what signal voltage is the gas detector pulse energy signal no longer in the linear range? | If the peak of the signal is higher than about 0.8 Volts. | Fact | [FELFastPulseEnergy]_JSR_30(2023).pdf | The method and algorithm described here have been shown to work at SwissFEL with its repetition rate of up to $1 0 0 \\mathrm { H z }$ . The optimization of the algorithm to process the data has been shown to be $1 0 0 \\%$ reliable even at the maximum $1 0 0 \\mathrm { H z }$ repetition rate, has no skipped points and... | 4 | Yes | 1 |
Expert | At what signal voltage is the gas detector pulse energy signal no longer in the linear range? | If the peak of the signal is higher than about 0.8 Volts. | Fact | [FELFastPulseEnergy]_JSR_30(2023).pdf | This manuscript describes the developments in hardware characterization, feedback and monitoring programs, and processing algorithms that allow the photon pulse energy monitor (PBIG) at SwissFEL to deliver absolute pulse energy evaluations on a shot-to-shot basis (Juranic´ et al., 2018). The PBIG is the renamed DESY-d... | augmentation | Yes | 0 |
Expert | At what signal voltage is the gas detector pulse energy signal no longer in the linear range? | If the peak of the signal is higher than about 0.8 Volts. | Fact | [FELFastPulseEnergy]_JSR_30(2023).pdf | 2.2. Algorithm for data-processing The core of the data processing and evaluation of the absolute pulse energy on a shot-to-shot basis is the evaluation of the ratio between the slow signals and the fast signals. The slow absolute evaluation from the XGMD has an integration time of about $1 0 { \\mathrm { ~ s } } .$ , ... | augmentation | Yes | 0 |
Expert | At what signal voltage is the gas detector pulse energy signal no longer in the linear range? | If the peak of the signal is higher than about 0.8 Volts. | Fact | [FELFastPulseEnergy]_JSR_30(2023).pdf | $$ where $I _ { \\mathrm { X G M D } }$ and ${ \\cal I } _ { \\mathrm { H A M P } }$ are the evaluations of the XGMD and HAMP signal data in the buffer, respectively. This constant is then used in further evaluations. A weighted average algorithm is used to evaluate the current conversion constant so that $$ C = W C _ ... | augmentation | Yes | 0 |
Expert | At what signal voltage is the gas detector pulse energy signal no longer in the linear range? | If the peak of the signal is higher than about 0.8 Volts. | Fact | [FELFastPulseEnergy]_JSR_30(2023).pdf | 3. Results and discussion The resulting evaluation of the absolute single-shot pulse energy matches both the absolute numbers measured by the XGMDs, and shows the shot-to-shot fluctuations of their amplitudes, as seen in Fig. 3. The fast measurement comparison was made under conditions that kept the HAMP gain voltage c... | augmentation | Yes | 0 |
Expert | At what signal voltage is the gas detector pulse energy signal no longer in the linear range? | If the peak of the signal is higher than about 0.8 Volts. | Fact | [FELFastPulseEnergy]_JSR_30(2023).pdf | Though the setup described is fast, an even better setup would be one where the evaluation of the pulse energy would depend completely on values measured from the HAMPs, their gain voltage and a photon energy. This is theoretically possible, but would require a long-term project to gather sufficient data to correlate t... | augmentation | Yes | 0 |
expert | Describe the SHINE dechirper | Flat, corrugated, metallic plates separated by an adjustable gap | Summary | Beam_performance_of_the_SHINE_dechirper.pdf | $$ Figure 6 compares the dipole and quadrupole wakes obtained by convolving with the actual bunch distribution \in SHINE and the analytical results verified with the simulated results from the ECHO2D code [22]. Assuming that the beam is close to (and nearly on) the axis, there is good agreement between the numerical an... | 1 | Yes | 0 |
expert | Describe the SHINE dechirper | Flat, corrugated, metallic plates separated by an adjustable gap | 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 | Describe the SHINE dechirper | Flat, corrugated, metallic plates separated by an adjustable gap | Summary | Beam_performance_of_the_SHINE_dechirper.pdf | $$ where $k _ { \\mathrm { q } } ( s )$ is the effective quadrupole strength, which changes with $s$ within the bunch length $l$ . For the case where the beam is near the axis, a short uniformly distributed bunch was deduced \in Ref. [25] to calculate the emittance growth after passing through the dechirper. As mention... | 1 | Yes | 0 |
expert | Describe the SHINE dechirper | Flat, corrugated, metallic plates separated by an adjustable gap | Summary | Beam_performance_of_the_SHINE_dechirper.pdf | $$ where $f ( q ) = n / d$ , and with $$ \\begin{array} { l } { n = q [ \\cosh [ q ( 2 a - y - y _ { 0 } ) ] - 2 \\cosh [ q ( y - y _ { 0 } ) ] } \\\\ { \\qquad + \\cosh [ q ( 2 a + y + y _ { 0 } ) ] ] } \\\\ { \\qquad - i k \\zeta [ \\sinh [ q ( 2 a - y - y _ { 0 } ) ] + \\sinh [ q ( 2 a + y + y _ { 0 } ) ] ] , } \\en... | 1 | Yes | 0 |
expert | Describe the SHINE dechirper | Flat, corrugated, metallic plates separated by an adjustable gap | Summary | Beam_performance_of_the_SHINE_dechirper.pdf | The effect of a high group velocity in the radiation pulse also merits discussion. At the end of the structure length, the pulse length can be expressed [1] as $l _ { \\mathrm { p } } = 2 h t L / a p$ . For the structural parameters of SHINE, we have $l _ { \\mathrm { p } } = 5 \\mathrm { m }$ which is much longer than... | 1 | Yes | 0 |
expert | Describe the SHINE dechirper | Flat, corrugated, metallic plates separated by an adjustable gap | Summary | Beam_performance_of_the_SHINE_dechirper.pdf | $$ 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] $$ \\begin{array} { r l } & { w _ { y \\mathrm { d } } \\approx \\displaystyle \\frac { Z _ { 0 } \\mathrm { c } \\pi ^ { 3 } } { 6 4 a ^ { 4 } } { \\mathit... | augmentation | Yes | 0 |
expert | Describe the SHINE dechirper | Flat, corrugated, metallic plates separated by an adjustable gap | Summary | Beam_performance_of_the_SHINE_dechirper.pdf | We next simply consider the quadrupole wake, where the beam is on-axis $( \\mathrm { y } _ { \\mathrm { c } } = 0 )$ . The transfer matrices for the focusing and defocusing quadrupole are given in Eq. (16), where $L$ is the length of the corrugated structure [25]. $$ \\begin{array} { r } { \\boldsymbol { R } _ { \\math... | augmentation | Yes | 0 |
IPAC | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | $$ where $$ F \\left( \\xi \\right) = \\int _ { - \\infty } ^ { \\xi } A ^ { \\prime } { } ^ { 2 } ( \\xi ^ { \\prime } ) d \\xi ^ { \\prime } , $$ $$ G \\left( \\xi \\right) = \\int _ { - \\infty } ^ { \\xi } A ( \\xi ^ { \\prime } ) A ^ { \\prime 2 } ( \\xi ^ { \\prime } ) d \\xi ^ { \\prime } , $$ $$ H \\left( \\xi ... | augmentation | NO | 0 |
IPAC | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | \\begin{array} { c l c r } { \\bar { x } , \\bar { y } = x , y } \\\\ { \\bar { p } _ { x , y } = \\displaystyle \\frac { P _ { x , y } } { \\bar { P } _ { s } } = \\displaystyle \\frac { p _ { x , y } P _ { s } } { \\bar { P } _ { s } } = \\displaystyle \\frac { p _ { x , y } } { 1 + \\delta } , } \\\\ { \\bar { p } _... | augmentation | NO | 0 |
IPAC | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | $$ \\epsilon _ { x } = C _ { q } \\gamma ^ { 2 } \\frac { I _ { 5 } } { I _ { 2 } - I _ { 4 } } $$ with ùëíùëÑ $C _ { q } = { \\frac { 5 5 } { 3 2 { \\sqrt { 3 } } } } { \\frac { \\hbar } { m c } } \\approx 3 . 8 3 2 \\times 1 0 ^ { - 1 3 } \\mathrm { { m } }$ and $$ \\left\\{ \\begin{array} { l l } { \\displaystyle ... | augmentation | NO | 0 |
IPAC | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | $$ where the dependency on $\\widehat { \\tau }$ of $Q _ { s } ( \\widehat { \\tau } )$ has been introduced. The rightmost integral is given by $$ \\begin{array} { r l } & { \\frac { 1 } { | \\alpha _ { x y } | } \\displaystyle \\int _ { 0 } ^ { \\infty } d J _ { y } f _ { y } ( J _ { y } ) \\delta \\left( J _ { y } - ... | augmentation | NO | 0 |
IPAC | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | $$ where $\\mathcal { K } _ { m }$ consists of homogeneous polynomials in $p$ and $q$ of $( m + 2 )$ degree $$ \\begin{array} { r l } & { \\mathcal { K } _ { 0 } = C _ { 2 , 0 } p ^ { 2 } + C _ { 1 , 1 } p q + C _ { 0 , 2 } q ^ { 2 } , } \\\\ & { \\mathcal { K } _ { 1 } = C _ { 3 , 0 } p ^ { 3 } + C _ { 2 , 1 } p ^ { 2... | augmentation | NO | 0 |
IPAC | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | $$ From Eqs. (3) and (4), it can be further observed that if $\\gamma \\sigma _ { z }$ is extremely large (i.e., $\\gamma \\sigma _ { z } \\infty ,$ ), the term ${ E } _ { s z }$ goes to zero, and Eq. (1) reduces to $$ \\begin{array} { c } { { \\phi \\approx \\displaystyle \\frac { 1 } { 4 \\pi \\varepsilon _ { 0 } } ... | augmentation | NO | 0 |
IPAC | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | $$ where the factors $E _ { 1 }$ and $E _ { 2 }$ are given by: $$ \\begin{array} { c } { { E _ { 1 } = \\displaystyle \\frac { H _ { e } } { a } c o s ( \\theta ) - \\displaystyle \\frac { K _ { a n } } { M _ { s a t } \\mu _ { 0 } a } s i n ^ { 2 } ( \\psi - \\theta ) } } \\\\ { { E _ { 2 } = \\displaystyle \\ \\frac ... | augmentation | NO | 0 |
IPAC | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | For a charged particle moving at a constant high $\\beta$ velocity, or being accelerated along its predominant $\\beta$ vector component, the magnetic and acceleration-dependent terms for an observer on-axis with $\\beta$ (i.e. in the direction of $\\mathbf { n }$ ) go to zero, and the electric field reduces as $$ \\be... | augmentation | NO | 0 |
IPAC | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | $$ where we have split the transformed phase space coordinates $$ u _ { k } = \\mathcal { M } _ { k } ( x ) $$ into orthogonal axes $u _ { k _ { \\parallel } } \\in \\mathbb { R } ^ { M }$ and $u _ { k _ { \\perp } } \\in \\mathbb { R } ^ { N - M }$ . In the absence of many views, various distributions may fit the data... | augmentation | NO | 0 |
IPAC | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | $$ where $E _ { z 0 } ( z ) \\equiv E _ { z } ( z , r = 0 )$ and similarly for $B _ { z 0 }$ . Then $$ \\frac { 2 } { r } F _ { \\perp } + F _ { z } ^ { \\prime } = - \\frac { \\beta _ { z } ^ { \\prime } } { \\beta _ { z } } \\frac { E _ { z 0 } } { \\beta _ { z } c } . $$ We can clean up the expression for $\\widetil... | augmentation | NO | 0 |
IPAC | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | $$ where $q _ { 1 } = \\sqrt { q ^ { 2 } + \\hat { \\nu } k ^ { 2 } }$ and $n = 2$ in region $I I$ and $n = 3$ in region $I I I$ , and in region $I V$ $$ \\left( \\begin{array} { c c } { { \\bar { E } _ { z } } } & { { \\bar { H } _ { z } } } \\\\ { { \\tilde { E } _ { x } } } & { { \\tilde { H } _ { x } } } \\end{arra... | augmentation | NO | 0 |
expert | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | File Name:Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf Alternating-Phase Focusing for Dielectric-Laser Acceleration Uwe Niedermayer,1,\\* Thilo Egenolf,1 Oliver Boine-Frankenheim,1,3 and Peter Hommelhoff2 1Technische Universit√§t Darmstadt, Schlossgartenstrasse 8, D-64289 Darmstadt, Germany $^ 2$ De... | 4 | NO | 1 |
IPAC | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | $$ \\phi _ { i + 2 } = - \\frac { 1 } { 1 + h x } \\left( \\partial _ { x } \\left( ( 1 + h x ) \\partial _ { x } \\phi _ { i } \\right) + \\partial _ { s } \\left( \\frac { 1 } { 1 + h x } \\partial _ { s } \\phi _ { i } \\right) \\right) . $$ From this recurrence relation, only two initial functions can be independen... | 1 | NO | 0 |
expert | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | Earnshaw‚Äôs theorem dictates that constant focusing cannot be achieved in all three spatial directions simultaneously [29]. Thus, at least two focusing directions have to be alternating. In conventional Alvarez linacs or in synchrotrons constant focusing is applied in the longitudinal direction and alternating quadrup... | 5 | NO | 1 |
expert | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | In this Letter we solve this outstanding problem with a laser-based scheme which allows transport and acceleration of electrons in dielectric nanostructures over arbitrary lengths. It is applicable to changing DLA period lengths, which is required to accelerate subrelativistic electrons. Moreover, we find the maximum t... | 1 | NO | 0 |
expert | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | $$ \\begin{array} { l } { { V ( x , y , s = s _ { f 1 } + \\Delta s ) = - V ( x , y , s = s _ { f 2 } + \\Delta s ) } } \\\\ { { \\displaystyle ~ = \\frac { q | e _ { 1 } | \\lambda _ { g } } { 2 \\pi } \\left[ \\frac { 1 } { 2 } \\left( \\frac { \\omega y } { \\beta \\gamma c } \\right) ^ { 2 } - \\frac { 1 } { 2 } \\... | augmentation | NO | 0 |
expert | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | $$ L ^ { f } = \\sum _ { n = 1 } ^ { p } \\lambda _ { g } ^ { ( n ) } , \\qquad L ^ { d } = \\sum _ { n = p + 1 } ^ { 2 p } \\lambda _ { g } ^ { ( n ) } , $$ $$ l ^ { f } = ( 2 \\pi - \\varphi _ { s } ^ { ( p ) } ) \\lambda _ { g } ^ { ( p ) } / \\pi , ~ l ^ { d } = ( \\pi - \\varphi _ { s } ^ { ( 2 p ) } ) \\lambda _ ... | augmentation | NO | 0 |
expert | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | $$ \\varepsilon ( y , y ^ { \\prime } ) = \\hat { \\gamma } y ^ { 2 } + 2 \\hat { \\alpha } y y ^ { \\prime } + \\hat { \\beta } y ^ { \\prime 2 } , $$ $$ \\varepsilon _ { L } ( \\Delta s , \\Delta s ^ { \\prime } ) = \\hat { \\gamma } _ { L } \\Delta s ^ { 2 } + 2 \\hat { \\alpha } _ { L } \\Delta s \\Delta s ^ { \\pr... | augmentation | NO | 0 |
expert | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | \\*niedermayer@temf.tu-darmstadt.de [1] K. Shimoda, Appl. Opt. 1, 33 (1962). [2] A. Lohmann, IBM Technical Note 5, 169, 1962. [3] R. J. England et al., Rev. Mod. Phys. 86, 1337 (2014). [4] E. A. Peralta, K. Soong, R. J. England, E. R. Colby, Z. Wu, B. Montazeri, C. McGuinness, J. McNeur, K. J. Leedle, D. Walz, E. B. So... | augmentation | NO | 0 |
expert | Explain the Earnshaw’s theorem | At least two focusing directions have to be alternating. | definition | Alternating-Phase_Focusing_for_Dielectric-Laser_Acceleration.pdf | $$ a ( z ) = \\sqrt { \\hat { \\beta } ( z ) \\frac { \\varepsilon _ { 0 } \\beta _ { 0 } \\gamma _ { 0 } } { \\beta ( z ) \\gamma ( z ) } } , $$ where the 0 indices denote initial values. Acceleration from $8 3 \\mathrm { k e V }$ to $1 \\mathrm { M e V }$ at $\\varphi _ { 0 } = 4 \\pi / 3$ , with an average gradient ... | augmentation | NO | 0 |
IPAC | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | One approach for addressing the issue posed by SBBU is through the introduction of an external magnetic lattice to correct for deviations in the beam trajectory due to wakefield effects. This approach is limited however in it’s maximum allowable accelerating gradient due to the fact that longitudinal wakefields scale... | augmentation | NO | 0 |
IPAC | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | $$ SIMULATIONS RESULTS Simulations are performed using QuickPIC [8], a 3-D quasi-static PIC code, with the simulation parameters specified in Table ??. The ellipticities were calculated from the transverse cross section of the blowout cavity by taking the gradient of the density above a specific threshold, which is typ... | augmentation | NO | 0 |
IPAC | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | This beam, with $\\sigma _ { z } = 9 5 \\mu \\mathrm { m }$ , is numerically injected into a $n _ { 0 } = 1 0 ^ { 1 3 } \\mathrm { c m } ^ { - 3 }$ plasma, yielding the condition with $k _ { p } \\sigma _ { z } \\simeq$ 2. The head of the beam is decelerated while the tail is accelerated, thus producing the desired dis... | augmentation | NO | 0 |
IPAC | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | BEAM TRANSPORT An electric discharge-based capillary plasma source is being built at UCLA [5]. The $8 \\mathrm { c m }$ long capillary is created by boring a $4 \\mathrm { m m }$ wide opening inside a macor structure with a single channel gas supply tube. The plasma density inside this capillary has been measured to be... | augmentation | NO | 0 |
IPAC | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | $$ \\sigma ^ { * 2 } = \\epsilon \\beta ^ { * } ( 1 + \\xi ^ { 2 } \\delta _ { p } ^ { 2 } ) , $$ where $\\epsilon$ is the beam emittance, $\\beta ^ { * }$ is the beta-function at the IP, $\\delta _ { p }$ is the relative momentum spread of the beam and $\\xi$ is the chromaticity at the IP. SYNCHROTRON RADIATION IN THE... | augmentation | NO | 0 |
IPAC | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | The physical solution of the quadratic equation is: $$ \\begin{array} { c } { { D _ { x } = \\displaystyle \\frac { ( S + 5 \\sqrt { \\epsilon _ { i n j } \\beta _ { x } } ) \\Delta } { \\Delta ^ { 2 } - 2 5 \\delta _ { c i r } ^ { 2 } } + } } \\\\ { { \\displaystyle \\frac { 5 \\sqrt { \\epsilon _ { c i r } \\beta _ {... | augmentation | NO | 0 |
IPAC | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | $$ 2 \\pi f \\Delta \\tau \\ll 1 , $$ where $f$ is the characteristic frequency of the wake, and $\\Delta \\tau$ is the distance between the rings. For the PETRA wake, dom inated by the resistive wall e!ects, a choice of $n _ { r } = 9$ works reasonably well. Figure 2 shows the radial discretization. NUMERICAL SIMULATI... | augmentation | NO | 0 |
IPAC | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | Table: Caption: Table 1: Beam Parameters at the Exit of the S-band Injector. Body: <html><body><table><tr><td>Injector exit parameters</td><td>Witness</td><td>Driver</td></tr><tr><td>Charge (pC)</td><td>30</td><td>200</td></tr><tr><td>Rms spot size (μm)</td><td>118</td><td>127</td></tr><tr><td>Rms length (fs)</td><td... | augmentation | NO | 0 |
IPAC | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | Table: Caption: Table 1: Comparison of Beam Dynamics for Three Different Input Distributions after Optimisation Body: <html><body><table><tr><td rowspan="2">Parameter</td><td colspan="3">Distributions</td></tr><tr><td>A</td><td>B</td><td>C</td></tr><tr><td>Emittance,εx (mm mrad)</td><td>6.19</td><td>5.21</td><td>5.00... | augmentation | NO | 0 |
IPAC | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | In the following simulation study, we will first evaluate the effect of horizontal impedance (dipole $^ +$ detuning) and then will take into account the vertical one. EFFECT OF HORIZONTAL IMPEDANCE The horizontal beam-beam cross-wake function has been given in Eq. (12) of Ref. [14], $$ W _ { x } ^ { ( - ) } ( z ) = - \... | augmentation | NO | 0 |
IPAC | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | $$ \\begin{array} { r } { \\beta _ { x } = \\sqrt { ( 1 + \\alpha _ { p } ^ { 2 } ) \\gamma } k _ { p } ^ { - 1 } } \\\\ { \\beta _ { y } = \\sqrt { \\displaystyle \\frac { ( 1 + \\alpha _ { p } ^ { 2 } ) \\gamma } { \\alpha _ { p } ^ { 2 } } } k _ { p } ^ { - 1 } , } \\end{array} $$ where, $\\gamma$ is the Lorentz fac... | augmentation | NO | 0 |
IPAC | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | Table: Caption: Table 1: Beam and DLW Parameters for DWA Experiments Body: <html><body><table><tr><td>Parameter</td><td></td></tr><tr><td>Beam Momentum</td><td>35.5MeV/c</td></tr><tr><td>Total Charge</td><td>85-100 pC</td></tr><tr><td>Normalised Emittance</td><td>~5 mm mrad</td></tr><tr><td>RMSBeamSizeatDLW</td><td>~1... | 1 | NO | 0 |
expert | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | In the misaligned case [Fig. 2(b)], on the contrary, the centroid is clearly deflected, with increasing displacement along the bunch. Figure 2(d) shows that the centroid position and the running sum follow the same trend along the bunch. This confirms the expectation that the amplitude of the transverse wakefields (and... | 1 | NO | 0 |
IPAC | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | Two DLW geometries are under active consideration, circular/cylindrical and planar/slab DLWs. Strong transverse fields are excited off-axis in both geometries, leading to beam breakup instability induced by small initial offsets [4]. A method for compensating this instability is required before applications of DWA can ... | 1 | NO | 0 |
IPAC | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | $$ \\begin{array} { r } { \\left[ ( 1 + \\nu _ { z } ) \\vec { W } _ { \\perp } - \\nu _ { z } \\vec { E } _ { i \\perp } + ( 1 - \\nu _ { z } ) \\vec { E _ { b \\perp } } \\right] \\Big | _ { \\partial \\Omega } = 0 , } \\end{array} $$ where $\\vec { \\pmb { W } } _ { \\perp }$ is the transverse plasma wake field and ... | 1 | NO | 0 |
expert | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | Figure 4 shows the position of the centroid at $t = 3 . 6$ ps (a), 4.1 ps (b), and 4.6 ps (c) behind the front of the bunch as a function of $n _ { P E }$ , for three misalignment distances (see Legend). The displacement, which is due to the effect of the dielectric wakefields, decreases when increasing $n _ { P E }$ b... | 5 | NO | 1 |
expert | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | Thus, when a bunch travels with transverse offset $( x , y )$ , parallel to its axis, it drives transverse dipolar wakefields along the bunch described by [16]: $\\begin{array} { r } { W _ { \\perp } ( t ) = w ( x , y ) \\int _ { 0 } ^ { t } n _ { b } ( t ) d t } \\end{array}$ , where the bunch front is at $t = 0$ . Th... | augmentation | NO | 0 |
expert | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | The dielectric capillary has radius $R _ { c } = 1 ~ \\mathrm { m m }$ and length $L = 1 0 ~ \\mathrm { c m }$ . The plasma is generated by a discharge pulse ${ \\sim } 4 5 5$ A peak current) flowing through the capillary after the introduction of hydrogen gas ${ \\sim } 1 0$ mbar) through a high-speed solenoid valve. ... | augmentation | NO | 0 |
expert | For a given transverse beam offset, would a higher of lower plasma density be preferred to reduce the transverse dielectric wakes? | A higher plasma density screens wakes more effectively | Reasoning | Experimental_Observation_of_Space-Charge_Field_Screening.pdf | \\*Contact author: livio.verra@lnf.infn.it [1] F. F. Chen, Introduction to Plasma Physics and Controlled Fusion (Springer International Publishing, New York, 2016). [2] F. Otsuka, T. Hada, S. Shinohara, and T. Tanikawa, Penetration of a radio frequency electromagnetic field into a magnetized plasma: One-dimensional pic... | augmentation | NO | 0 |
IPAC | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | File Name:SCATTERED_SPECTRA_FROM_INVERSE_COMPTON_SOURCES.pdf SCATTERED SPECTRA FROM INVERSE COMPTON SOURCESOPERATING AT HIGH LASER FIELDS ANDHIGH ELECTRON ENERGIES B. Terzi!‚Üí, E. Breen, P. Rogers, R. Shahan, E. Johnson, G. A. Kra"t1 Old Dominion University, Norfolk, Virginia, USA G. Wilson, Regent University, Virgini... | augmentation | NO | 0 |
IPAC | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | Table: Caption: Table 1: RMS emittances for an $1 8 \\mathrm { G e V }$ ESR lattice with fractional tunes $( \\boldsymbol { Q _ { x } } , \\boldsymbol { Q _ { y } } , \\boldsymbol { Q _ { s } } ) = ( 0 . 1 2 , 0 . 1 0 , 0 . 0 5 )$ . Body: <html><body><table><tr><td></td><td>Ea,RMs [nm]</td><td>E b,RMs [nm]</td></tr><t... | augmentation | NO | 0 |
IPAC | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | The first of the coupled equations describes the change of energy due to a longitudinal electric field caused by a gradient of the charge distribution. The second equation can be rewritten as $d z _ { i } / d s = \\eta _ { i } / \\gamma ^ { 2 }$ meaning that relativistic particles with an energy offset change their lon... | augmentation | NO | 0 |
IPAC | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | Example of radiation spectra from CR and CB can be observed in Fig. 1. This experiment was conducted at the Mainzer Mikrotron (MAMI), where a beam of electrons of $6 0 0 \\mathrm { M e V }$ impinges on a $0 . 3 1 \\mathrm { m m }$ thick diamond crystal along the (110) plane at various angles. Directly at angle $0 \\mu ... | augmentation | NO | 0 |
IPAC | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | As an example from [18], Fig. 3 the simulation of the radiation emission probability by a $1 0 \\mathrm { G e V }$ positron beam with $3 0 \\mu \\mathrm { r a d }$ of divergence on silicon CU with $\\lambda _ { u } = 3 3 4 \\mu \\mathrm { m }$ , amplitude $A = 1 . 2 8 \\mathrm { n m }$ and strength parameter $k = 0 . 4... | augmentation | NO | 0 |
IPAC | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | Table: Caption: Table 1: STAR Parameters Body: <html><body><table><tr><td colspan="2">Electron beam parameters</td></tr><tr><td>Energy (MeV) Bunch charge (pC)</td><td>140 500</td></tr><tr><td>Energy spread (rms, %)</td><td>0.24</td></tr><tr><td>E n,x,y (mm mrad)</td><td>1.32</td></tr><tr><td>ge,x,y(μm)</td><td>18</td... | augmentation | NO | 0 |
IPAC | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | $$ where $\\omega _ { c }$ is the critical frequency defined at half power spectrum, $E _ { 0 }$ is the particle energy, $\\gamma$ is the relativistic factor, $\\boldsymbol { a }$ is the fine structure constant and $r _ { e }$ is the electron’s classical radius. For $\\Upsilon \\gg 1$ , the photon spectrum is given b... | augmentation | NO | 0 |
IPAC | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | Turning on the effect of ideal Siberian snakes fixes the closed-orbit spin tune at $\\nu _ { 0 } ~ = ~ 1 / 2$ , which prevents the crossing of any 1st-order intrinsic resonances. Nevertheless, higher-order intrinsic resonances can be crossed by large-amplitude particles for which the spin tune deviates from _x0012__x00... | 1 | NO | 0 |
Expert | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | 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... | 1 | NO | 0 |
Expert | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | 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 ... | 4 | NO | 1 |
Expert | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | 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 | NO | 0 |
Expert | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | 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... | 4 | NO | 1 |
IPAC | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | Maximal_spontaneous_photon_emission_and_energy_loss_from_free_electrons.pdf | For ELI-NP parameters (Table 1), the e#cacy of FM is evaluated as a function of $a _ { 0 }$ . The results in Fig. 6 show close to perfect recovery of the peak spectral density at $a _ { 0 } = 1$ . CONCLUSION Accurate computation of scattered spectra from ICS operating in the nonlinear Compton regime requires properly a... | 1 | NO | 0 |
Expert | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | 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 | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | 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 | NO | 0 |
Expert | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | 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 | NO | 0 |
Expert | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | 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 | NO | 0 |
Expert | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | 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 | NO | 0 |
Expert | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | 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 | How do bound states in the continuum (BICs) enhance Smith-Purcell radiation? | BICs offer high-Q resonances embedded in the radiation continuum, creating large modal overlaps and enabling emission rates to diverge when phase-matched with electron trajectories. | Reasoning | 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 | NO | 0 |
expert | How does Carilli’s interferometric method measure beam size? | By analyzing fringe visibilities from synchrotron light passing through a non-redundant aperture mask and fitting them to a Gaussian source model. | Reasoning | Carilli_2024.pdf | The derived coherences, ie. visibility fractional amplitudes (relative to the zero spacing) corrected for the voltage gains, are show in Figure 10, for both 3-hole and 5-hole data, and listed in Table II. Gain fitting is not possible with 3-hole data since the problem becomes under-constrained, so the three hole cohere... | 2 | Yes | 0 |
expert | How does Carilli’s interferometric method measure beam size? | By analyzing fringe visibilities from synchrotron light passing through a non-redundant aperture mask and fitting them to a Gaussian source model. | Reasoning | Carilli_2024.pdf | dominated by a phenomenon such as CCD read noise. Figure 26 shows a plot of the mean coherences and rms of the coherences over the 30 record time series assuming no bias, and subtracting a bias of 3.7 counts per pixel. The coherences are systematically lower by about 2% with no bias subtracted, and the rms values are u... | 2 | Yes | 0 |
expert | How does Carilli’s interferometric method measure beam size? | By analyzing fringe visibilities from synchrotron light passing through a non-redundant aperture mask and fitting them to a Gaussian source model. | Reasoning | Carilli_2024.pdf | Note that the target source size is $\\leq 6 0 \\mu m$ , which at a distance of $\\mathrm { 1 5 . 0 5 m }$ implies an angular size of $\\leq 0 . 8 4 \\$ . For comparison, the angular interferometric fringe spacing of our longest baseline in the mask of $2 2 . 6 \\mathrm { m m }$ at $5 4 0 ~ \\mathrm { n m }$ wavelength... | 4 | Yes | 1 |
expert | How does Carilli’s interferometric method measure beam size? | By analyzing fringe visibilities from synchrotron light passing through a non-redundant aperture mask and fitting them to a Gaussian source model. | Reasoning | Carilli_2024.pdf | Notice that, for the 6-hole mask Figure 8, the u,v data points corresponding to the vertical and horizontal 16mm baseline have roughly twice the visibility amplitude as neighboring points (and relative to the 5-hole mask). This is because these are now redundantly sampled, meaning the 16mm horizontal baseline now inclu... | 4 | Yes | 1 |
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Accel-IR Benchmark: A Gold Standard for Particle Accelerator Physics
This repository contains the Accel-IR Benchmark, a domain-specific Information Retrieval (IR) dataset for particle accelerator physics. It was developed as part of the Master's Thesis "From Dataset to Optimization: A Benchmarking Framework for Information Retrieval in the Particle Accelerator Domain" by Qing Dai (University of Zurich, 2025), in collaboration with the Paul Scherrer Institute (PSI).
Dataset Configurations
This benchmark is available in two configurations. You can load specific versions based on your evaluation needs:
| Configuration | Rows | Description | Use Case |
|---|---|---|---|
expert_core |
390 | Purely expert-annotated pairs. Labeled by 7 domain experts (PhDs/Researchers) from PSI. | Precise evaluation against human ground truth. |
augmented |
1,357 | The expert_core + curated hard negatives. The negatives were generated using a expert-validated automatic annotation pipeline. |
Realistic IR evaluation with many more negatives than positives. |
Dataset Structure
Data Fields
Each row in the dataset represents a query-document pair with the following columns:
Source: The referenced paper or an IPAC publication, source of the chunks.Question: The domain-specific scientific question.Answer: Answer to the question.Question_type: The category of the question, simulating diverse information needs:Fact: Specific details or parameters.Definition: Explanations of concepts/terms.Reasoning: Logic behind phenomena or mechanisms.Summary: Key points or conclusions.
Referenced_file(s): Referenced papers for the questions, provided by experts.chunk_text: The text passage retrieved from domain-expert-referenced papers or IPAC conference papers.expert_annotation(Core only): The raw relevance score given by domain experts on a 5-point Likert scale:1: Irrelevant2: Partially Irrelevant3: Hard to Decide (Excluded from Core)4: Partially Relevant5: Relevant
specific to paper: Indicates if the question is "Context-Dependent" (answerable only by the referenced paper) or "General" (answerable by broader domain knowledge).Label: The binary ground truth used for evaluation metrics (nDCG/MAP).1(Relevant): Derived from expert scores 4 & 5.0(Irrelevant): Derived from expert scores 1 & 2, or pipeline hard negatives.
Creation Methodology
Expert Core:
- Created by 7 domain experts from the Electron Beam Instrumentation Group at PSI.
- Experts reviewed query-chunk pairs and annotated them on a 1-5 scale using a custom interface.
- Pairs labeled as "3 - Not Sure" were removed to ensure no ambiguity.
Augmentation (Hard Negatives):
- To simulate realistic retrieval scenarios where negatives far outnumber positives, the core dataset was augmented.
- Hard Negatives were generated using an expert-validated automatic annotation pipeline.
Usage
You can load the datasets using the Hugging Face datasets library.
Load the Expert Core (390 pairs)
from datasets import load_dataset
# Load the pure expert-annotated subset
ds_core = load_dataset("qdai/Accel-IR", "expert_core", split="test")
print(ds_core[0])
Citation
If you use this dataset, please cite:
Qing Dai, "From Dataset to Optimization: A Benchmarking Framework for Information Retrieval in the Particle Accelerator Domain", Master's Thesis, University of Zurich, 2025.
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