DOI: 10.5061/dryad.66t1g1kfs
title: Ultrashort electron pulse generation with single-femtosecond-level Jitter

description: This dataset contains the numerical and image data underlying all figures
 of the associated manuscript on ultrashort electron pulse generation and
 timing characterization. The files include experimentally measured
 terahertz (THz) electric field waveforms, time-dependent electron beam
 deflection data, retrieved electron pulse temporal profiles, arrival time
 drift measurements, and numerical simulation results obtained using CST
 and ASTRA. Numerical data are provided in CSV format with clearly labeled
 variables and units, and CST monitor outputs are provided as
 high-resolution TIFF images. The dataset enables independent
 visualization, quantitative reanalysis, and reproduction of the reported
 results. No legal, ethical, or access restrictions apply.
description: # Ultrashort electron pulse generation with single-femtosecond-level
 jitter Dataset DOI:
 [10.5061/dryad.66t1g1kfs](https://doi.org/10.5061/dryad.66t1g1kfs) ##
 Description of the data and file structure This dataset contains numerical
 and image data underlying all figures of the associated manuscript. Files
 include experimentally measured terahertz (THz) waveforms, electron beam
 timing measurements, retrieved ultrafast pulse temporal profiles, and
 simulation results obtained using CST and ASTRA. Numerical data are
 provided as CSV files. CST simulation monitor outputs are provided as
 high-resolution TIFF files. *CST: *CST Studio Suite
 (Computer Simulation Technology) is a commercial electromagnetic
 simulation software used to model electric fields and particle dynamics.
 *ASTRA*: ASTRA (A Space Charge Tracking Algorithm) is a particle tracking
 simulation code used to simulate electron beam dynamics in radio-frequency
 accelerators. ### Files and variables #### File: fig1b.csv
 **Description:** Time-resolved THz electric field waveform measured via
 THz streaking. *THz electric field*: Terahertz (THz) electric field refers
 to the electric field component of electromagnetic radiation in the
 terahertz frequency range (10¹² Hz). In this dataset, it describes the
 time-dependent electric field used to interact with the electron beam.
 *THz streaking: *THz streaking is a time-resolved
 measurement technique in which a time-varying THz electric field imparts a
 transverse momentum to an electron beam, allowing reconstruction of its
 temporal profile. *Normalized*: Normalized indicates that the data have
 been scaled relative to their maximum value or another reference value,
 resulting in dimensionless quantities typically ranging between 0 and 1.
 *Time units:* ps = picosecond (10^⁻12^ s) fs = femtosecond (10^⁻15^ s)
 ##### Variables * **Time_ps**: Time coordinate (picoseconds) *
 **THz_field_normalized**: Normalized THz electric field amplitude
 (dimensionless) #### File: fig2b_t1.tif, fig2b_t2.tif, fig2b_t3.tif,
 fig2b_t4.tif **Description:** CST-simulated spatial distributions of
 electron bunches at different time points (t1–t4). *Particle
 density*: Particle density refers to the simulated spatial distribution of
 electrons in the beam, represented by relative intensity in the simulation
 images. ##### Variables * Image intensity represents simulated particle
 density. #### File: fig3a.tif **Description:** Measured time-dependent
 electron beam deflection diagram. *Electron beam deflection diagram*: A
 two-dimensional image showing how the transverse position (or angle) of an
 electron beam varies as a function of temporal delay between the beam and
 an external field. *Temporal delay*: Temporal delay refers to the relative
 time shift between two synchronized signals, such as the electron beam and
 the THz field. *Beam deflection*: Beam deflection refers to the angular or
 positional change of the electron beam caused by interaction with an
 external electric field. *Electron signal*: Electron signal refers to the
 detected intensity of electrons recorded on a detector (e.g., phosphor
 screen or camera), represented as image intensity. ##### Variables *
 Horizontal axis: temporal delay * Vertical axis: beam deflection * Image
 intensity represents measured electron signal. #### File: fig3a.csv
 **Description:** Measured temporal profile of the electron bunch. #####
 Variables * **Time_fs**: Time coordinate (femtoseconds) *
 **Normalized_intensity**: Normalized electron intensity (dimensionless)
 #### File: fig3d.csv **Description:** Measured temporal distribution of
 the electron pulse train. *Temporal distribution*: Temporal distribution
 describes how electron intensity varies as a function of time. *Electron
 pulse train*: Electron pulse train refers to a sequence of temporally
 separated electron pulses within a single measurement window. #####
 Variables * **Pulse1_time_fs**: Time of pulse 1 (femtoseconds) *
 **Pulse1_normalized_intensity**: Normalized intensity of pulse 1
 (dimensionless) * **Pulse2_time_fs**: Time of pulse 2 (femtoseconds) *
 **Pulse2_normalized_intensity**: Normalized intensity of pulse 2
 (dimensionless) * **Pulse3_time_fs**: Time of pulse 3 (femtoseconds) *
 **Pulse3_normalized_intensity**: Normalized intensity of pulse 3
 (dimensionless) #### File: fig4b.csv **Description:** Measured electron
 arrival time drift with and without the THz-driven device. *Arrival time
 jitter*: Refers to fluctuations in the arrival time of electron pulses
 relative to a reference timing signal. *THz-driven device*: The THz-driven
 antenna structure combined with the beam aperture used for timing
 stabilization. *With_device*: Refers to measurements performed with the
 THz-driven timing stabilization device active. *Without_device*: Refers to
 measurements performed without the device. ##### Variables *
 **Time_minutes**: Measurement time (minutes) *
 **Arrival_time_without_device_fs**: Electron arrival time without device
 (femtoseconds) * **Arrival_time_with_device_fs**: Electron arrival time
 with device (femtoseconds) #### File: fig4c.csv
 **Description:** Simulation results showing influence of RF amplitude
 fluctuations on arrival time jitter. *RF (radio-frequency)*:
 Electromagnetic accelerating field used in the electron gun. *Influence of
 RF amplitude fluctuations*: Refers to the simulated effect of variations
 in RF accelerating field amplitude on electron arrival time stability.
 ##### Variables * **RF_amplitude_variation_percent**: RF amplitude
 variation (%) * **Simulated_arrival_time_jitter_fs**: Simulated arrival
 time jitter (femtoseconds) #### File: fig4d.csv
 **Description:** Simulation results showing influence of RF phase
 fluctuations on arrival time jitter. *Influence of RF phase fluctuations*:
 Refers to the simulated effect of variations in RF accelerating phase on
 electron arrival time stability. ##### Variables * **RF_phase_deg**: RF
 phase variation (degrees) * **Simulated_arrival_time_jitter_fs**:
 Simulated arrival time jitter (femtoseconds) #### File: fig4e.csv
 **Description:** Measured electron arrival time as a function of UV laser
 delay. *UV laser*: UV laser refers to an ultraviolet laser pulse used to
 generate or synchronize the electron beam. ##### Variables *
 **UV_delay_fs**: UV laser delay time (femtoseconds) *
 **Arrival_time_with_device_fs**: Arrival time with device (femtoseconds) *
 **Arrival_time_without_device_fs**: Arrival time without device
 (femtoseconds) * **SD_without_device_fs**: Standard deviation of arrival
 time without device (femtoseconds) #### File: fig5b_t1.tif, fig5b_t2.tif,
 fig5b_t3.tif, fig5b_t4.tif **Description:** CST-simulated electric field
 distribution and beam evolution at different simulation stages. *Electric
 field distribution*: Electric field distribution describes the spatial
 variation of electric field magnitude within the simulated structure.
 *Beam evolution*: Beam evolution refers to the simulated change in
 electron beam properties (e.g., length or spatial distribution) during
 propagation. ##### Variables * Image intensity represents electric field
 magnitude. #### File: fig5c.csv **Description:** Simulated evolution of
 electron bunch length. ##### Variables * **Time_fs**: Time coordinate
 (femtoseconds) * **Bunch_length_fs**: Electron bunch length (femtoseconds)
 ## Code/software The data are provided in CSV and TIFF formats and can be
 opened using standard data analysis or image viewing software. No
 specialized software is required. ## Access information Other publicly
 accessible locations of the data: * None. Data was derived from the
 following sources: * The data were generated as part of this study and
 were not derived from external sources.