Relative Drift Research Articles

On Velocity Stopbands in Electrostatic Solitary Wave Propagation in Magnetospheric Plasma in the Presence of an Ion Beam—Application in the Solar Wind

Satellite observations in the Earth’s magnetosphere suggest a coexistence of different types of ion populations, such as protons and heavier helium ions (alpha particles) transported by the solar wind. We have undertaken an investigation, from first principles, of the conditions for the occurrence of electrostatic solitary waves in such a multi-ion plasma environment. Nonlinear analysis has been employed to explore the effect of an ion beam on the occurrence of stopbands in a multicomponent plasma consisting of Boltzmann electrons and two ion species, modeled as cold and warm (adiabatic) ions. A “stopband” is an interval of pulse speed (mach (Mach number) values in which solitary waves cannot propagate. Such stopbands are known to exist in relation to fast ion-acoustic solitary waves (exclusively). Our parametric analysis reveals that the stopband widens over the range of cold ion charge density (values) upon increasing speed of a hot ion beam moving along the direction of wave propagation. However, the stopband becomes narrower in the case of a counterpropagating beam. Similarly, the streaming of a cold ion beam fluid along (or antiparallel) to the wave direction leads to the narrowing (or widening, respectively) of the stopband. The fast soliton existence (velocity) domain is characterized by two critical points (a crossover and a turning point), which are affected by the beam. Our study could be relevant to understanding energy dissipation processes in the fast solar wind associated with relative drifts between the major (protons) and minor (alpha particles) ions which results in the heating of both species.

Electron Shock Drift Acceleration at a Low-Mach-number, Low-plasma-beta Quasi-perpendicular Shock

Shock drift acceleration (SDA) plays an important role in generating high-energy electrons at quasi-perpendicular shocks, but its efficiency in low-beta plasmas is questionable. In this article, we perform a two-dimensional particle-in-cell simulation of a low-Mach-number, low-plasma-beta quasi-perpendicular shock, and find that the electron cyclotron drift instability is unstable at the leading edge of the shock foot, which is excited by the relative drift between the shock-reflected ions and the incident electrons. The electrostatic waves triggered by the electron cyclotron drift instability can scatter and heat the incident electrons, which facilitates their escape from the shock’s loss cone. These electrons are then reflected by the shock and energized by SDA. In this way, the acceleration efficiency of SDA at low-plasma-beta quasi-perpendicular shocks is highly enhanced.

Solar Orbiter Observations of Proton and Alpha Particle Kinetic Signatures Related to the Presence of Switchbacks in the Inner Heliosphere: A Case Study

We investigate how ions, namely protons and alpha particles, kinetically react to the presence of strong deflections in the magnetic field, the so-called switchbacks, in the first stream of slow Alfvénic wind observed by Solar Orbiter at the heliocentric distance of 0.64 au. We focus on an isolated, large-scale switchback, and we study in detail ion kinetic properties. Beyond the expected correlation between the magnetic deflection and ion velocity related to the Alfvénic nature of the switchbacks, we find that, within the switchback, proton and alpha particle densities increase, suggesting ongoing wave activity. Very interestingly, we observe a clear correlation between the magnetic deflection and alpha particle temperature, while no correlation has been found with proton temperature. This is an indication of a possible role played by switchbacks in preferentially heating heavy ions. Our results suggest that the presence of switchbacks can induce a deformation of the proton velocity distribution function, while the preferential heating of alpha particles could be due to a denser secondary beam and a smaller relative drift speed between the beam and core.

Decade‐Long Ozone Profile Record From Suomi NPP OMPS Limb Profiler: Assessment of Version 2.6 Data

AbstractWe evaluate a decadal ozone profile record derived from the Suomi National Polar‐orbiting Partnership (SNPP) Ozone Mapping and Profiler Suite (OMPS) Limb Profiler (LP) satellite instrument. In 2023, the OMPS LP data were re‐processed with the new version 2.6 retrieval algorithm that combines measurements from the ultraviolet (UV) and visible (VIS) parts of the spectra. It employs the second order Tikhonov regularization to retrieve a single vertical ozone profile between 12.5 km (or cloud tops) and 57.5 km with a vertical resolution of about 1.9–2.5 km between 20 and 55 km. The algorithm uses radiances measured at six UV ozone‐sensitive wavelengths (295, 302, 306, 312, 317, and 322 nm) paired with 353 nm, and one VIS wavelength at 606 nm combined with 510 and 675 nm to form a triplet. Each wavelength pair or triplet is used over a limited range of tangent altitudes where the sensitivity to ozone change is strongest. A new aerosol correction scheme was implemented based on a gamma‐function particle size distribution. In addition, numerous calibration changes that affected ozone retrievals were applied to measured LP radiances, including updates in altitude registration, radiometric calibration, stray light, and spectral registration. The key version 2.6 enhancement is the improved stability of the LP ozone record confirmed by the reduction in relative drifts between LP ozone and correlative measurements, linked previously to a drift in the version 2.5 LP altitude registration.

Comparison of 5 and 10 Storey Frame Buildings and 5 and 10 Storey Shear Wall-Frame Buildings Under the Effect of Maras Earthquake According to the Turkish Building Earthquake Code 2018

In this study, the differences in the displacements, base shear forces, relative storey drifts and foundation stresses under different earthquake data on different storeys of shear wall frame systems and framed systems are investigated by using SAP2000 program. Within the scope of the study, four buildings with 5-storey frame, 5-storey shear wall frame, 10-storey frame and 10 storey shear wall frame are modelled. All four buildings were designed to be identical with 4 spans in X and Y directions and each span was designed as 5 meters. The height of each floor is designed as 3 meters for all four buildings. In sheared structures, shear walls are designed to be 4 meters from the corner columns to the columns closest to them. The earthquake data to be influenced on all four structures are the earthquake data from the Earthquake Hazard Map of Turkey published by AFAD at the coordinates of 41° latitude, 27° longitude of Kırklareli province, Luleburgaz district. Another earthquake parameter was taken from station 4615 during the earthquake in Kahramanmaras. The data recorded by station 4615 for the 7.6 Mw earthquake in Kahramanmaras was applied to all four structures. These two earthquake data were imposed on these four structures in order to compare the resulting displacements, relative storey drifts, base shear forces and foundation stresses. Since the structures are all symmetrical in both X and Y directions, only one direction of the displacements was calculated. As a result, when both the earthquake data from the Earthquake Hazard Map and the Kahramanmaras earthquake data were applied to these four structures, it was observed that the maximum values of the displacements occurred at the top floors of all structures and the effect of the Kahramanmaras earthquake data was higher in the displacements, relative storey drifts, base shear forces and foundation stresses than the effect of the other earthquake data.

Energy Transport and Conversion Within Earth's Supercritical Bow Shock: The Role of Intense Lower‐Hybrid Whistler Waves

AbstractDetailed analysis of a high Mach number quasiperpendicular Earth bow shock crossing by the Magnetospheric Multiscale (MMS) spacecraft fleet reveal that lower‐hybrid (LH) whistler waves generated in the shock foot region transport energy predominately along the shock surface and slightly toward the shock ramp in the shock normal incidence frame, where wave energy accumulates and is dissipated into the plasma. This suggests the LH whistlers play an integral role in energy reconfiguration at high Mach number collisionless shocks with ramifications to plasma heating. The multipoint observations are used to quantify the wave characteristic parameters (via interferometry), Poynting fluxes, and energy conversion rates D, and to assess their scale dependencies and spatial and temporal properties. The whistler associated energy transport and conversion are found to depend on scale and location within the layer. High‐frequency electrostatic waves yield largest values of D. However, the dominant net energy exchange contribution is from the LH whistlers. In the foot spatially temporally coherent net energy exchange from the plasma to whistlers is observed, whereas deeper in the ramp net wave energy dissipation to the plasma is observed exhibiting significant space‐time variability. These results are consistent with the modified two stream instability driven by the relative drift between reflected ions and electrons as the mechanism for wave growth in the foot. Owing to strong electron heating, whistler energy dissipation in the ramp is attributed to Landau damping, which out‐competes the destabilizing effect of the reflected ion and electron drift.

Studying animal locomotion with multiple data loggers: quantifying time drift between tags

Temporal accuracy is a fundamental characteristic of logging technology and is needed to correlate data streams. Single biologgers sensing animal movement (accelerometers, gyroscope, magnetometers, collectively inertial measurement unit; IMU) have been extensively used to study the ecology of animals. To better capture whole body movement and increase the accuracy of behavior classification, there is a need to deploy multiple loggers on a single individual to capture the movement of multiple body parts. Yet due to temporal drift, accurately aligning multiple IMU datasets can be problematic, especially as deployment duration increases. In this paper we quantify temporal drift and errors in commercially available IMU data loggers using a combination of robotic and animal borne experiments. The variance in drift rate within a tag is over an order of magnitude lower (σ = 0.001 s h−1) than the variance between tags (σ = 0.015 s·h−1), showing that recording frequency is a characteristic of each tag and not a random variable. Furthermore, we observed a large offset (0.54 ± 0.016 s·h−1) between two groups of tags that had differing recording frequencies, and we observed three instances of instantaneous temporal jumps within datasets introducing errors into the data streams. Finally, we show that relative drift rates can be estimated even when deployed on animals displaying various behaviors without the tags needing to be simultaneously moved. For the tags used in this study, drift rates can vary significantly between tags, are repeatable, and can be accurately measured in the field. The temporal alignment of multiple tag datasets allows researchers to deploy multiple tags on an individual animal which will greatly increase our knowledge of movement kinematics and expand the range of movement characteristics that can be used for behavioral classification.

Исследование кварцевых резонаторов в миниатюрных металлокерамических корпусах с целью дальнейшего применения в термокомпенсированных генераторах

With the advent of new technologies, the requirements for the sources of reference vibrations are becoming more stringent. They must be compact, quickly reach frequency, operate in a wide temperature range and have a small relative frequency drift in the operating temperature range. Changes in ambient temperature are the most destabilizing factor for the oscillator output frequency. Ensuring frequency stability over a wide temperature range is a pressing task. Thermal compensation allows increasing frequency stability over a wide range of operating temperatures. This is achieved by compensating for the effect of the destabilizing factor on the generator so that the frequency drift tends to zero as the temperature changes. Temperature-compensated quartz oscillators are highly stable and have a short readiness time. However, to create generators with a frequency stability of ± 0,1 ppm, imported components are required, which makes their production difficult in modern conditions. A technological chain is created at the JSC «LIT-PHONON», which allows producing a quartz resonator using only Russian components. The goal is to use these resonators in temperature-compensated oscillators with frequency stability of ± 0,1 ppm. However, the analysis showed that the resonators have problems with frequency drift over time during operation at a maximum operating temperature of + 85 ºС. Additional adjustment of generators during operation is required. It is also revealed that some Russian components are not ideally suited to the developed technological process, which may negatively affect the yield of suitable products. The measuring setup also has an error of ± 0,5 ppm, which does not allow an accurate assessment of the frequency stability of the resonators.

Weak Solar Radio Bursts from the Solar Wind Acceleration Region Observed by the Parker Solar Probe and Its Probable Emission Mechanism

The Parker Solar Probe (PSP) provides us with an unprecedentedly close approach to the observation of the Sun and hence the possibility of directly understanding the elementary process that occurs on the kinetic scale of particles' collective interaction in solar coronal plasmas. We report a type of weak solar radio burst (SRB) that was detected by PSP when it passed a low-density magnetic channel during its second encounter phase. These weak SRBs have a low starting frequency of ∼20 MHz and a narrow frequency range from a few tens of MHz to a few hundred kHz. Their dynamic spectra display a strongly evolving feature of the intermediate relative drift rate decreasing rapidly from above 0.01 s−1 to below 0.01 s−1. Analyses based on common empirical models of solar coronal plasmas indicate that these weak SRBs originate from a heliocentric distance of ∼1.1–6.1 R S (the solar radius), a typical solar wind acceleration region with a low-β plasma, and that their sources have a typical motion velocity of ∼v A (Alfvén velocity) obviously lower than that of the fast electrons required to effectively excite SRBs. We propose that solitary kinetic Alfvén waves with kinetic scales could be responsible for the generation of these small-scale weak SRBs, called solitary wave radiation.

Electron-field instability: Excitation of electron plasma waves by an electric field

Electric fields are commonplace in plasmas and affect transport by driving currents and, in some cases, instabilities. The necessary condition for instability in collisionless plasmas is commonly understood to be described by the Penrose criterion, which quantifies a sufficient relative drift between different populations of particles that must be present for wave amplification via inverse Landau damping. For example, electric fields generate drifts between electrons and ions that can excite the ion-acoustic instability. Here, we use particle-in-cell simulations and linear stability analysis to show that the electric field can drive a fundamentally different type of kinetic instability, named the electron-field instability. This instability excites electron plasma waves with wavelengths ≳30λDe, has a growth rate that is proportional to the electric field strength, and does not require a relative drift between electrons and ions. The Penrose criterion does not apply when accounting for the electric field. The large value of the observed frequency, near the electron plasma frequency, further distinguishes it from the standard ion-acoustic instability, which oscillates near the ion plasma frequency. The ubiquity of macroscopic electric fields in quasineutral plasmas suggests that this instability is possible in a host of systems, including low-temperature and space plasmas. In fact, damping from neutral collisions in such systems is often not enough to completely damp the instability, adding to the robustness of the instability across plasma conditions.

Formation of electron beam-like components in low-Mach-number quasi-perpendicular shock: Particle-in-cell simulation

Collisionless shocks with low Alfvénic Mach numbers are expected to accelerate electrons, but the underlying physics are still unsolved. Two-dimensional particle-in-cell simulation of low-Mach-number quasi-perpendicular shock in low-β is performed to study the physics of formation of beam-like components with respect to background magnetic fields. The incoming electrons can be trapped and scattered to have velocities along the shock surface by the electrostatic wave in the foot region owing to the free energy in the relative drift between shock reflected ions and upstream electrons. Then fractional electrons can be reflected by the mirror force at the shock overshoot when escaping from the loss cone. The reflection by the mirror force makes the electrons gain quasi-parallel velocities, and the electrons are accelerated in the quasi-parallel direction during trapping in the immediate downstream, forming a beam-like component with respect to magnetic fields. Our results shown in this paper explain the physics of beam formation and could be helpful for accounting for type II radio bursts.

Observations and Modeling of Unstable Proton and α Particle Velocity Distributions in Sub-Alfvénic Solar Wind at Parker Solar Probe Perihelia

Past observations show that solar wind (SW) acceleration occurs inside the sub-Alfvénic region, reaching the local Alfvén speed at typical distances ∼10–20 solar radii (R s ). Recently, Parker Solar Probe (PSP) traversed regions of sub-Alfvénic SW near perihelia in encounters E8–E12 for the first time, providing data in these regions. It became evident that the properties of the magnetically dominated SW are considerably different from the super-Alfvénic wind. For example, there are changes in the relative abundances and drift of α particles with respect to protons, as well as in the magnitude of magnetic fluctuations. We use data of the magnetic field from the FIELDS instrument, and construct ion velocity distribution functions (VDFs) from the sub-Alfvénic regions using Solar Probe ANalyzer for Ions data, and run 2.5D and 3D hybrid models of proton-α sub-Alfvénic SW plasma. We investigate the nonlinear evolution of the ion kinetic instabilities in several case studies, and quantify the transfer of energy between the protons, α particles, and the kinetic waves. The models provide the 3D ion VDFs at the various stages of the instability evolution in the SW frame. By combining observational analysis with the modeling results, we gain insights on the evolution of the ion instabilities, the heating and the acceleration processes of the sub-Alfvénic SW plasma, and quantify the exchange of energy between the magnetic and kinetic components. The modeling results suggest that the ion kinetic instabilities are produced locally in the SW, resulting in anisotropic heating of the ions, as observed by PSP.

Investigation of Relative Story Shifts in Buildings with Projection Irregularities at Different Ratios

There are 3 major fault lines in our country, which is exposed to thousands of earthquakes every year, namely the North Anatolian Fault Line, the East Anatolian Fault Line and the West Anatolian Fault Line. Therefore, earthquake effects are more important in terms of the structural behavior of the buildings built in our country. It is very important for building safety to design buildings as regularly as possible during the design phase. However, sometimes this is not possible for reasons such as architectural designs. In the study, 6 different models with the irregularity type of A3-Existence of Projections in the Plane and the symmetric reference model were analyzed according to mode coupling. The models analyzed in the study were modeled in three dimensions from the SAP2000 program. As a result of the analysis, the relative storey drift performances of the models under the effect of earthquakes were examined. Comparisons were made in line with the results obtained from the analyzes and the relative folds of the structures with A3 irregularity type were made. Comments have been made about the effect on the displacements.

Communication area estimation for decentralized control of nanosatellites swarm

The problem of relative drift elimination between the satellites in the swarm is considered in the paper. The proposed decentralized control takes into account a communication constraint such as limited size of communication area. Only the satellites within the communication area can be identified by relative motion determination system. The control aim is to eliminate the mean relative drift between all the satellites inside the communication area. The purpose of the work is to study the performance of the proposed decentralized control algorithm. It is shown that the system matrix of differential equations for the vector of relative drifts is related to the Laplacian matrix of the communication graph. In the case of the connected swarm, all but one eigenvalues of the system are negative, and the remaining one is equal to zero. It means that all the relative drifts converge to the same value under the proposed control. The speed of convergence is defined by the minimum absolute eigenvalue that depends on the graph topology. The initial drift and the convergence speed make it possible to estimate the communication distance that provides the connectivity of the graph. Considering normally distributed errors of the initial velocity after the launch, it is possible to estimate the distance between any two satellites after the convergence. It allows us to estimate the communication distance that ensures the relative drift elimination between all the satellites in the swarm. The obtained estimations are validated using Monte Carlo simulations. In numerical simulations the swarm of 3U CubeSats in low-Earth orbit is considered. The decentralized control is implemented by differential aerodynamic drag via the change of cross-sectional area using onboard reaction wheels.

A reference-free dual-comb spectroscopy calibrated by passive devices

Dual-comb spectroscopy has enabled new approaches for optical precision measurements. Although Doppler-limited resolution can be achieved over long-time scales across a large bandwidth, the development of dual-comb spectroscopy is hindered by strict demands for light source stability. Typically, expensive and complex self-reference systems are required to lock the carrier-envelope offset frequency (fceo) of the laser. Additionally, simply locking the repetition frequency (frep) to a radio frequency reference source still results in residual relative timing jitter between light sources. Here we extracted the relative fceo fluctuation between the frep-locked lasers from the high-precision passive notch filtering characteristics of the phase-shifted fiber Bragg grating and then eliminated it through online phase calibration. By introducing a passive broadband Fabry–Perot cavity with excellent thermal wavelength stability, we subsequently corrected residual relative timing jitter with online wavelength calibration, and the standard deviation of the relative wavelength drift was reduced to less than 0.4 pm within the full operating range. The spectral profile can also be extracted and removed by the Fabry–Perot cavity through intensity calibration. By calibrating these three dimensions, we built a reference-free post-calibration dual-comb spectroscopy and used this powerful tool to measure the Fabry–Perot cavity resonance peaks, the notch filtering narrow band of phase-shifted fiber Bragg gratings, and the absorption characteristics of hydrogen cyanide gas. The system achieves a spectral resolution of 0.8 pm over a bandwidth of more than 100 nm. This low-cost and convenient scheme provides new ideas for the application of dual-comb spectroscopy systems.

Parametric analysis of heat flux inhibition in the solar wind: a macroscopic quasilinear approach

Abstract Magnitudes of electron temperature anisotropy and solar wind heat flux are defined with different physical mechanisms e.g. microinstabilities, interparticle collisions, and adiabatic expansion. In the dilute space plasma limit, the present study assumes the interplay between anisotropic core-halo electron components, their relative drift, and relative density of the halo electrons to determine the dynamics of backward and forward-propagating whistler heat flux instabilities along the ambient magnetic field. To investigate the feedback effects of these micro-instabilities in reshaping solar wind distributions and the total heat flux regulation, we formulate quasilinear kinetic equations on the basis of taking the macroscopic velocity moments. For the same input parameters of linear analysis, numerical solutions of the quasilinear equations indicate the time-scale variations, electrons and protons population, wave intensities, and constraints on the heat flux. In future perspective of the global-kinetic solar wind model, the present formalism may be an important step with the inclusion of radial and nonthermal effects.

Frequency-Based Sensor Interface with Dynamic Offset Compensation

Sensor interfaces need to be robust and accurate for many applications. This is more challenging for sensor systems operating in radiation environments because the mismatch between components grows as a result of the absorbed total ionizing dose (TID). In frequency-based sensor interfaces, the frequency drift of the voltage-controlled oscillator (VCO) can create dynamic output offset, gain, and linearity errors unless a calibration algorithm is included. In this paper, a digital intensive dynamic offset cancelation technique is proposed for an open loop VCO-based sensor to digital converter, which is achieved by making periodic adjustments to the average center biasing voltage of one of the VCOs in a differential architecture, in effect to make their center frequencies match. A simulation of the behavioral model of the proposed architecture was developed and hardware implementation of the whole system was performed on an FPGA by emulating, with digital modules, the characteristics of the two VCO outputs modulated with differential inputs. The results showed that the output offset error was reduced from around 5% to 0.1% for a relative oscillators’ drift close to 10% of the tuning range, and the SNDR is relatively maintained when subjected to variable relative VCO drifts.

Performance-Based Assessment of RC Building with Short Columns Due to the Different Design Principles

Many factors affect the earthquake vulnerability of reinforced concrete (RC) structures, constituting a large part of the existing building stock. Short column in RC structures is one of the reasons for earthquake damage. Significant damages may occur due to brittle fractures in structural elements when the shear resistances are exceeded under the effect of high shear stress in short columns formed due to architectural and topographic reasons. This study created structural models for three situations: the hill slope effect, band-type window and mezzanine floor, which may cause short column formation. The structural analyses by SAP2000 were compared with the reference building model with no short columns. Structural analyses were performed separately according to strength-based and deformation-based design approaches in the updated Türkiye Building Earthquake Code (TBEC-2018). Short column formation; the effects on soft-storey irregularity, the relative storey drifts, column shear force, plastic rotation in columns, roof displacement, base shear force and column damage levels were investigated. As a result of the analysis, it was determined that the relative drifts from the first floor of the building decreased significantly due to the band-type window and slope effect, which caused the second storey to fall into the soft-storey status. In addition, short-column formation caused a significant increase in both plastic rotation demand and shear force in short columns.

A comparison of the influence of plasmoid-drift mechanisms on plasma fuelling by cryogenic pellets in ITER and Wendelstein 7-X

Pellet injection is the most promising technique to achieve efficient plasma core fuelling, key for attaining stationary scenarios in large magnetic confinement fusion devices. In this paper, the injection of pellets with different volumes and speeds into standard plasma scenarios in ITER (tokamak) and Wendelstein 7-X (stellarator) is studied by modeling the pellet ablation and particle deposition, focusing on the evaluation of the expected differences in pellet plasmoid drifts in tokamaks and stellarators. Since the efficiency of the damping-drift mechanisms is predicted to depend on the magnetic configuration, device-specific characteristics are expected for the temporal evolution of the plasmoid drift acceleration. For instance, plasmoid-internal Pfirsch–Schlüter currents dominate the drift damping process for stellarators, while plasmoid-external currents are more relevant for tokamaks. Also, relatively larger drifts are in principle expected for W7-X due to higher field gradients in relation to machine dimensions. However, shorter plasmoid-internal charge reconnection lengths result in the drift damping due to internal Pfirsch–Schlüter currents being more effective than in a tokamak. Therefore, the average relative drift displacement during the whole plasmoid homogenization may a priori be comparable in both magnetic configurations. Moreover, High Field Side (HFS) injection is expected to be highly advantageous to maximize pellet particle deposition in ITER, whereas it may only be beneficial in medium to high β environments in W7-X. Finally, there may be means for the optimization of pellet injection configurations in both ITER and W7-X for the considered plasma scenarios despite the sizeable differences in the relative importance of the mechanisms of plasmoid drift acceleration and deceleration in play.

The Damage Assessment for Rapid Response (DARR) Method and its Application to Different Ground-Motion Levels and Building Types

AbstractSeismic recordings in buildings and on the ground are increasingly available due to the increment and expansion of seismic monitoring networks worldwide. However, most urban strong-motion networks consist of stations installed at the ground or, less frequently, in selected building’s basement. It is, therefore, of utmost importance to develop methods that can provide estimates of expected structural damage, starting from earthquake recordings at the ground level. Damage Assessment for Rapid Response (DARR) provides first-level estimates of the expected damage to buildings, based on ground-motion recordings and simple information on buildings’ characteristics. In this work, we apply DARR using both weak and strong ground-motion recordings available for different low- and mid-rise building typologies. A total of 9 buildings and 19 earthquake recordings were analyzed. DARR reproduces the shaking at the building’s top, and estimates the peak structural relative displacement or average interstory drift. Results show that the method works well for the considered building types and ground-motion levels for the estimation of relative and total displacements using first-order assessments. Comparison with the previously defined thresholds allows the estimation of expected damage. Our results (i.e., no damage for most buildings and events) are consistent with the absence of damaging events in northeastern Italy in the studied period (2019–2021). For a school building in central Italy, which was heavily damaged by the 2016 Central Italian sequence, DARR correctly predicted this fact.