Publication

LMA observations of upward lightning flashes at the Santis Tower initiated by nearby lightning activity

Publications associées (31)

On the Initiation of Upward Negative Lightning by Nearby Lightning Activity: An Analytical Approach

Upward lightning occurs generally from tall structures. The mechanism of the initiation of upward lightning is not yet fully understood. Upward lightning can be classified into two categories based on either the absence or the presence of other lightning a ...

2021

Bidirectional Recoil Leaders in Upward Lightning Flashes Observed at the Säntis Tower

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Amirhossein Mostajabi, Antonio Sunjerga

We report the observation of three negative upward flashes recorded by a high-speed camera at the Säntis Tower during the Summer of 2019. The camera was operating at 10,000 fps and an exposure time of 99 μs. Simultaneous measurements of the lightning curre ...

2021

The laser lightning rod project

Farhad Rachidi-Haeri, Marcos Rubinstein, Jean-Pierre Wolf, Pierre Walch, Mohammad Azadifar, Clemens Herkommer, Amirhossein Mostajabi, Thomas Produit, Antonio Sunjerga

Lightning is highly destructive due to its high power density and unpredictable character. Directing lightning away would allow to protect sensitive sites from its direct and indirect impacts (electromagnetic perturbations). Up to now, lasers have been una ...

2021

Impact of Frequency-Dependent Soil Models on Grounding System Performance for Direct and Indirect Lightning Strikes

Farhad Rachidi-Haeri

The goal of this article is to investigate the effect of frequency-dependent soil models on the performance of grounding electrodes subjected to lightning strikes. Several soil models are examined while accounting for the variation of soil resistivity and ...

2021

Estimation of the Lightning Performance of Overhead Lines Accounting for Different Types of Strokes and Multiple Strike Points

Farhad Rachidi-Haeri

Dealing with lightning performance computation, researchers usually consider only negative downward first return strokes and the relevant channel-base peak current distribution. The aim of this article is to account for the lightning flash mechanism, which ...

2021

Lightning-Induced Voltages on Overhead Distribution Lines Computed through Analytical Expressions for the Electromagnetic Fields

Farhad Rachidi-Haeri, Marcos Rubinstein

The evaluation of lightning ElectroMagnetic (EM) fields represents the most cumbersome part of the lightning-induced voltages computation process. Their evaluation is usually performed through a numerical routine or with simplified analytical expressions, ...

2021

Could Macroscopic Dark Matter (Macros) Give Rise to Mini-Lightning Flashes out of a Blue Sky without Clouds?

Farhad Rachidi-Haeri, Marcos Rubinstein

A recent study pointed out that macroscopic dark matter (macros) traversing through the Earth’s atmosphere can give rise to hot and ionized channels similar to those associated with lightning leaders. The authors of the study investigated the possibility t ...

2021

Analytical Expressions for Lightning Electromagnetic Fields With Arbitrary Channel-Base Current. Part II: Validation and Computational Performance

Farhad Rachidi-Haeri, Marcos Rubinstein

This article provides the implementation procedure, the validation, and some considerations on the computational efforts of the analytical expressions developed for the lightning electromagnetic fields presented in the companion paper. The validation is pr ...

2021

A Characterisation of Alpine Mesocyclone Occurrence

Alexis Berne, Marco Gabella, Monika Feldmann, Urs Martin Germann

This work presents a characterisation of mesocyclone occurrence and frequency in the Alpine region, as observed from the Swiss operational radar network; 5 years of radar data are processed with a thunderstorm detection and tracking algorithm and subsequen ...

2021

Analytical Expressions for Lightning Electromagnetic Fields With Arbitrary Channel-Base Current—Part I: Theory

Marcos Rubinstein

The article provides analytical expressions for the electromagnetic fields generated by a lightning return stroke characterized by a channel-base current with arbitrary time waveform, in presence of either a perfectly conducting or a lossy ground, assuming ...

2021

An Efficient FDTD Method to Calculate Lightning Electromagnetic Fields Over Irregular Terrain Adopting the Moving Computational Domain Technique

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Wenhao Hou, Qilin Zhang

We present an improved finite-difference time domain (FDTD) method based on the moving computational domain technique for the calculation of lightning-generated fields over large-scale irregular terrain. In the improved method, a spatial window moving alon ...

2020