D. Giardini
A5108111322- Pulsars and Gravitational Waves Research
- Geophysics and Gravity Measurements
- Radio Astronomy Observations and Technology
- Advanced Frequency and Time Standards
- Astrophysics and Cosmic Phenomena
- Solar and Space Plasma Dynamics
- Cosmology and Gravitation Theories
- Particle accelerators and beam dynamics
- Computational Physics and Python Applications
- Dark Matter and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Particle Detector Development and Performance
- Particle Accelerators and Free-Electron Lasers
- Scientific Measurement and Uncertainty Evaluation
- Neutrino Physics Research
- Ionosphere and magnetosphere dynamics
- Scientific Research and Discoveries
- Astronomical Observations and Instrumentation
- Soil Moisture and Remote Sensing
- Advanced Electrical Measurement Techniques
- Geophysics and Sensor Technology
- Gamma-ray bursts and supernovae
- Electromagnetic Launch and Propulsion Technology
- Digital and Cyber Forensics
- Planetary Science and Exploration
ETH Zurich
2012-2024
Royal Observatory
2018-2020
UK Astronomy Technology Centre
2018-2020
European Space Astronomy Centre
2020
École Polytechnique Fédérale de Lausanne
2005
We report the first results of LISA Pathfinder in-flight experiment. The demonstrate that two free-falling reference test masses, such as those needed for a space-based gravitational wave observatory like LISA, can be put in free fall with relative acceleration noise square root power spectral density 5.2±0.1 fm s^{-2}/sqrt[Hz], or (0.54±0.01)×10^{-15} g/sqrt[Hz], g standard gravity, frequencies between 0.7 and 20 mHz. This value is lower than requirement by more factor 5 within 1.25...
In the months since publication of first results, noise performance LISA Pathfinder has improved because reduced Brownian due to continued decrease in pressure around test masses, from a better correction noninertial effects, and calibration electrostatic force actuation. addition, availability numerous long measurement runs, during which no perturbation is purposely applied allowed with good statistics down 20 μHz. The Letter presents measured differential acceleration figure, at...
We present an in-depth analysis of the LISA Pathfinder differential acceleration performance over entire course its science operations, spanning approximately 500 days. find: (1) The evolution Brownian noise that dominates amplitude spectral density (ASD), for frequencies f≳1 mHz, is consistent with decaying pressure due to outgassing a single gaseous species. (2) Between f=36 μHz and 1 ASD shows 1/f tail in excess almost constant amplitude, ≃20% fluctuations period few days, no particular...
In this paper, we describe the current status of LISA Pathfinder mission, a precursor mission aimed at demonstrating key technologies for future spacebased gravitational wave detectors, like LISA.Since much flight hardware has already been constructed and tested, will show that performance measurements analysis these components lead to an expected which is significant improvement over requirements, actually reaches requirements entire measurement band.
Measurements of electrostatic forces on free-falling test masses--2 kg metal cubes--are carried out for the first time in an environment constructed space-based gravitational wave detectors (a spacecraft 1.5 million km away from Earth).
The Space Technology 7 Disturbance Reduction System (ST7-DRS) is a NASA technology demonstration payload that operated from January 2016 through July 2017 on the European Agency's (ESA) LISA Pathfinder spacecraft. joint goal of and ESA missions was to validate key technologies for future space-based gravitational wave observatory targeting source-rich millihertz band. two primary components ST7-DRS are micropropulsion system based colloidal micro-Newton thrusters (CMNTs) control...
The science operations of the LISA Pathfinder mission have demonstrated feasibility sub-femto-g free fall macroscopic test masses necessary to build a gravitational wave observatory in space such as LISA. While main focus interest, i.e., optical axis or $x$-axis, has been extensively studied, it is also great importance evaluate stability spacecraft with respect all other degrees freedom (d.o.f.). current paper dedicated study: exhaustive and quantitative evaluation imperfections dynamical...
We report on the first subpicometer interferometer flown in space. It was part of ESA's Laser Interferometer Space Antenna (LISA) Pathfinder mission and performed fundamental measurement positional angular motion two free-falling test masses. The worked immediately, stably, reliably from switch until end with exceptionally low residual noise ${32.0}_{\ensuremath{-}1.7}^{+2.4}\text{ }\text{ }\mathrm{fm}/\sqrt{\mathrm{Hz}}$, significantly better than required. present an upper limit for sensor...
We report on the development of LISA Technology Package (LTP) experiment that will fly onboard Pathfinder mission European Space Agency in 2008. first summarize science rationale aimed at showing operational feasibility so-called transverse–traceless coordinate frame within accuracy needed for LISA. then show briefly basic features instrument and we finally discuss its projected sensitivity extrapolation results to
LISA Pathfinder, the second of European Space Agency's Small Missions for Advanced Research in Technology (SMART), is a dedicated technology demonstrator joint ESA/NASA Laser Interferometer Antenna (LISA) mission. The technologies required are many and extremely challenging. This coupled with fact that some flight hardware cannot be fully tested on ground due to Earth-induced noise led implementation Pathfinder mission test critical environment. essentially mimics one arm constellation by...
We report on the performance of capacitive gap-sensing system Gravitational Reference Sensor board LISA Pathfinder spacecraft. From in-flight measurements, has demonstrated a performance, down to 1 mHz, that is ranging between 0.7 and $1.8\text{ }\text{ }\mathrm{aF}\text{ }{\mathrm{Hz}}^{\ensuremath{-}1/2}$. That translates into sensing noise test mass motion within 1.2 $2.4\text{ }\mathrm{nm}\text{ }{\mathrm{Hz}}^{\ensuremath{-}1/2}$ in displacement 83 $170\text{ }\mathrm{nrad}\text{...
In a previous article [1], we have reported on the first subpicometer interferometer flown in space as part of ESA's LISA Pathfinder mission, and shown residual sensor noise to be level ${32.0}_{\ensuremath{-}1.7}^{+2.4}\text{ }\text{ }\mathrm{fm}/\sqrt{\mathrm{Hz}}$. This review provides deeper more complete overview full system its interferometric mission performance under varying operational conditions, allowing much detailed view model. We also include optical measurements rotations...
A comprehensive summary of the measurements made to characterize test-mass charging due space environment during LISA Pathfinder mission is presented. Measurements residual charge test mass after release by grabbing and positioning mechanism show that initial masses was negative all releases, leaving with a potential in range from $\ensuremath{-}12$ $\ensuremath{-}512$. Variations neutral rate between 21.7 $30.7\text{ }\text{ }e\text{ }{\mathrm{s}}^{\ensuremath{-}1}$ were observed over...
The (LPF) mission successfully demonstrated the feasibility of technology needed for future space borne gravitational wave observatory LISA. A key subsystem under study was laser interferometer, which measured changes in relative distance between two test masses (TMs). It achieved a sensitivity <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"...
LISA Pathfinder (LPF), the second of European Space Agency's Small Missions for Advanced Research in Technology (SMART), is a dedicated technology validation mission future spaceborne gravitational wave detectors, such as proposed eLISA mission. Pathfinder, and its scientific payload - Package will test, flight, critical technologies required low frequency detection: it put two test masses near-perfect free-fall control measure their motion with unprecedented accuracy. This achieved through...
The LISA Pathfinder charge management device was responsible for neutralising the cosmic ray induced electric that inevitably accumulated on free-falling test masses at heart of experiment. We present measurements made ground and in-flight quantify performance this contactless discharge system which based photo-emission under UV illumination. In addition, a two-part simulation is described developed alongside hardware. Modelling absorbed light within sensor carried out with GEANT4 software...
LISA Pathfinder (LPF) was a technology pioneering mission designed to test key technologies required for gravitational wave detection in space. In the low frequency regime (milli-Hertz and below), where space-based observatories will operate, temperature fluctuations play crucial role since they can couple into interferometric measurement masses' free-fall accuracy many ways. A dedicated subsystem, with noise levels 10$\,\mu$K$\,$Hz$^{-1/2}$ down $1\,$mHz part of diagnostics unit on board...
The LISA Pathfinder (LPF) mission has demonstrated the ability to limit and measure fluctuations in acceleration between two free falling test masses down sub-femto-g levels. One of key elements achieve such a level residual is drag control. In this scheme spacecraft used as shield against any external disturbances by adjusting its relative position reference mass. actuators move are cold gas micropropulsion thrusters. paper, we report in-flight characterization these thrusters term noise...
We present an in depth analysis of the transient events, or glitches, detected at a rate about one per day differential acceleration data LISA Pathfinder. show that these glitches fall two rather distinct categories: fast transients interferometric motion readout on side, and true force events other. The former are rare ordinary conditions. second may last from seconds to hours constitute majority glitches. physical statistical properties both categories, including cross-analysis with other...
Abstract Galactic cosmic-ray (GCR) energy spectra observed in the inner heliosphere are modulated by solar activity, polarity and structures of interplanetary origin. A high counting rate particle detector (PD) aboard LISA Pathfinder , meant for subsystems diagnostics, was devoted to measurement GCR energetic integral fluxes above 70 MeV n −1 up 6500 counts s . PD data were gathered with a sampling time 15 s. Characteristics dependence flux recurrent depressions Forbush decrease dated 2016...
LISA Pathfinder (LPF) was a European Space Agency mission with the aim to test key technologies for future space-borne gravitational-wave observatories like LISA. The main scientific goal of LPF demonstrate measurements differential acceleration between free-falling masses at sub-femto-$g$ level, and understand residual in terms physical model stray forces, displacement readout noise. A step toward reaching goals correct calibration dynamics LPF, which three-body system composed by two...
LISA Pathfinder (LPF) has been a space-based mission designed to test new technologies that will be required for gravitational wave observatory in space. Magnetically driven forces play key role the instrument sensitivity low-frequency regime (mHz and below), measurement band of interest observatory. The magnetic field can couple susceptibility remanent moment from masses disturb them their geodesic movement. carried on-board dedicated subsystem with noise levels 10 $ \rm nT \ Hz^{-1/2}$ 1...
Preparations for the LISA Pathfinder mission have reached an exciting stage.Tests of engineering model (EM) optical metrology system recently been completed at Albert Einstein Institute, Hannover, and flight tests are now underway.Significantly, they represent first complete integration testing space-qualified hardware on level.The results test procedures these campaigns will be utilized directly in ground-based tests, subsequently during in-flight operations.In addition, allow valuable data...
LISA Pathfinder satellite was launched on 3 December 2015 toward the Sun–Earth first Lagrangian point (L1) where Technology Package (LTP), which is main science payload, will be tested. LTP achieves measurements of differential acceleration free-falling test masses (TMs) with sensitivity below within 1–30 mHz frequency band in one-dimension. The spacecraft itself responsible for dominant gravitational field acting two TMs. Such a force interaction could contribute significant amount noise...