A5116306108- Pulsars and Gravitational Waves Research
- Nuclear physics research studies
- Radio Astronomy Observations and Technology
- Geophysics and Gravity Measurements
- Advanced Frequency and Time Standards
- Astrophysics and Cosmic Phenomena
- Scientific Measurement and Uncertainty Evaluation
- Cosmology and Gravitation Theories
- Atomic and Molecular Physics
- Solar and Space Plasma Dynamics
- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Particle Detector Development and Performance
- Cold Atom Physics and Bose-Einstein Condensates
- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Superconducting Materials and Applications
- Ionosphere and magnetosphere dynamics
- Quantum chaos and dynamical systems
- Soil Moisture and Remote Sensing
- Geomagnetism and Paleomagnetism Studies
- Rare-earth and actinide compounds
- Computational Physics and Python Applications
Institut d'Estudis Espacials de Catalunya
2012-2025
Institute of Space Sciences
2016-2025
Université Paris Cité
2024
Universidad Politécnica de Madrid
1993-2024
Laboratoire AstroParticule et Cosmologie
2024
University of Trento
2018-2020
Istituto Nazionale di Fisica Nucleare, Trento Institute for Fundamental Physics And Applications
2018-2020
Telefonica Research and Development
2009
Universidad Autónoma de Madrid
2009
Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas
2009
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...
Electrostatic force actuation is a key component of the system geodesic reference test masses (TM) for LISA orbiting gravitational wave observatory and in particular performance at low frequencies, below 1 mHz, where sensitivity limited by stray noise. The needs to apply forces order 10−9 N while limiting fluctuations measurement band levels approaching 10−15 N/Hz1/2. We present here design, based on audio-frequency voltage carrier signals, results its in-flight with Pathfinder mission. In...
LISA Pathfinder was a mission designed to test key technologies required for gravitational wave detection in space. Magnetically driven forces play role the instrument sensitivity low-frequency regime, which corresponds measurement band of interest future space-borne observatories. Magnetic-induced couple mass motion, introducing contribution relative acceleration noise between free falling masses. In this Letter we present first complete estimate term performance model. Our results set...
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 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 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"...
We study the behavior of shell effects, like pairing correlations and shape deformations, with excitation energy in atomic nuclei. The analysis is carried out finite temperature Hartree-Fock-Bogoliubov method a range density dependent force. For first time, properties associated octupole hexadecupole deformation superdeformation as function are studied. Calculations for well quadrupole deformed 164Er 162Dy, superdeformed 152Dy, 224Ra, spherical 118Sn nuclei shown. find, particular, level...
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...
We present a study of the tilt-to-length coupling noise during LISA Pathfinder mission and how it depended on system's alignment. Tilt-to-length is unwanted angular lateral spacecraft or test mass motion into primary interferometric displacement readout. It was one major sources in likewise expected to be source LISA. demonstrate here that recently derived published analytical model describes dependency alignment two freely falling masses. This verified with data taken before after...
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...
A simple expression to compute the quantum discord between two orbitals in fermion systems is derived using parity superselection rule. As correlation depends on basis chosen, we discuss a special orbital basis, natural one. We show that correlations pairs disappear when pairing tensor zero, i.e., particle number symmetry preserved. The Hartree-Fock within Slater determinant state, Hartree-Fock-Bogoliubov quasiparticle vacuum, or ground state of Hamiltonian with and their corresponding are...