Author
M. de Deus Silva
Other affiliations: Max Planck Society
Bio: M. de Deus Silva is an academic researcher from European Space Agency. The author has contributed to research in topics: Pathfinder & Acceleration. The author has an hindex of 10, co-authored 26 publications receiving 862 citations. Previous affiliations of M. de Deus Silva include Max Planck Society.
Papers
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European Space Agency1, Leibniz University of Hanover2, Paris Diderot University3, Imperial College London4, University of Rome Tor Vergata5, University of Trento6, Airbus Defence and Space7, fondazione bruno kessler8, University of Birmingham9, Institut de Ciències de l'Espai10, ETH Zurich11, UK Astronomy Technology Centre12, INAF13, University of Urbino14, European Space Operations Centre15, University of Zurich16, University of Glasgow17, Polytechnic University of Catalonia18, Goddard Space Flight Center19, University of Florence20
TL;DR: The first results of the LISA Pathfinder in-flight experiment 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 a relative acceleration noise with a square root of the power spectral density.
Abstract: We report the first results of the LISA Pathfinder in-flight experiment. The results 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 a relative acceleration noise with a square root of the power spectral density of 5.2 +/- 0.1 fm s(exp -2)/square root of Hz, or (0.54 +/- 0.01) x 10(exp -15) g/square root of Hz, with g the standard gravity, for frequencies between 0.7 and 20 mHz. This value is lower than the LISA Pathfinder requirement by more than a factor 5 and within a factor 1.25 of the requirement for the LISA mission, and is compatible with Brownian noise from viscous damping due to the residual gas surrounding the test masses. Above 60 mHz the acceleration noise is dominated by interferometer displacement readout noise at a level of (34.8 +/- 0.3) fm square root of Hz, about 2 orders of magnitude better than requirements. At f less than or equal to 0.5 mHz we observe a low-frequency tail that stays below 12 fm s(exp -2)/square root of Hz down to 0.1 mHz. This performance would allow for a space-based gravitational wave observatory with a sensitivity close to what was originally foreseen for LISA.
523 citations
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European Space Agency1, Leibniz University of Hanover2, Imperial College London3, Paris Diderot University4, University of Trento5, fondazione bruno kessler6, University of Urbino7, University of Birmingham8, ETH Zurich9, UK Astronomy Technology Centre10, Institut de Ciències de l'Espai11, European Space Operations Centre12, University of Zurich13, University of Glasgow14, Polytechnic University of Catalonia15, Goddard Space Flight Center16, University of Florida17
TL;DR: This performance provides an experimental benchmark demonstrating the ability to realize the low-frequency science potential of the LISA mission, recently selected by the European Space Agency.
Abstract: In the months since the publication of the first results, the noise performance of LISA Pathfinder has improved because of reduced Brownian noise due to the continued decrease in pressure around the test masses, from a better correction of noninertial effects, and from a better calibration of the electrostatic force actuation. In addition, the availability of numerous long noise measurement runs, during which no perturbation is purposely applied to the test masses, has allowed the measurement of noise with good statistics down to
20
μ
Hz
. The Letter presents the measured differential acceleration noise figure, which is at
(
1.74
±
0.01
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fm
s
−
2
/
√
Hz
above 2 mHz and
(
6
±
1
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×
10
fm
s
−
2
/
√
Hz
at
20
μ
Hz
, and discusses the physical sources for the measured noise. This performance provides an experimental benchmark demonstrating the ability to realize the low-frequency science potential of the LISA mission, recently selected by the European Space Agency.
271 citations
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European Space Agency1, Max Planck Society2, Paris Diderot University3, Imperial College London4, University of Trento5, Airbus Defence and Space6, University of Birmingham7, ETH Zurich8, UK Astronomy Technology Centre9, Institut de Ciències de l'Espai10, University of Urbino11, European Space Operations Centre12, University of Zurich13, University of Glasgow14, Polytechnic University of Catalonia15, Goddard Space Flight Center16
TL;DR: Electrostatic measurements made on board the European Space Agency mission LISA Pathfinder are the first made in a relevant environment for a space-based gravitational wave detector and resolve the stochastic nature of the TM charge buildup due to interplanetary cosmic rays and theTM charge-to-force coupling through stray electric fields in the sensor.
Abstract: We report on electrostatic measurements made on board the European Space Agency mission LISA Pathfinder. Detailed measurements of the charge-induced electrostatic forces exerted on free-falling test masses (TMs) inside the capacitive gravitational reference sensor are the first made in a relevant environment for a space-based gravitational wave detector. Employing a combination of charge control and electric-field compensation, we show that the level of charge-induced acceleration noise on a single TM can be maintained at a level close to 1.0 fm s-2 Hz-1/2 across the 0.1–100 mHz frequency band that is crucial to an observatory such as the Laser Interferometer Space Antenna (LISA). Using dedicated measurements that detect these effects in the differential acceleration between the two test masses, we resolve the stochastic nature of the TM charge buildup due to interplanetary cosmic rays and the TM charge-to-force coupling through stray electric fields in the sensor. All our measurements are in good agreement with predictions based on a relatively simple electrostatic model of the LISA Pathfinder instrument.
73 citations
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TL;DR: 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 Space Agency's (ESA) LISA Pathfinder spacecraft as mentioned in this paper.
Abstract: 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 Space Agency’s (ESA) LISA Pathfinder spacecraft. The joint goal of the NASA and ESA missions was to validate key technologies for a future space-based gravitational wave observatory targeting the source-rich millihertz band. The two primary components of ST7-DRS are a micropropulsion system based on colloidal micro-Newton thrusters (CMNTs) and a control system that simultaneously controls the attitude and position of the spacecraft and the two free-flying test masses (TMs). This paper presents our main experimental results and summarizes the overall performance of the CMNTs and control laws. We find the CMNT performance to be consistent with preflight predictions, with a measured system thrust noise on the order of 100 nN/Hz in the 1 mHz≤f≤30 mHz band. The control system maintained the TM-spacecraft separation with an RMS error of less than 2 nm and a noise spectral density of less than 3 nm/Hz in the same band. Thruster calibration measurements yield thrust values consistent with the performance model and ground-based thrust-stand measurements, to within a few percent. We also report a differential acceleration noise between the two test masses with a spectral density of roughly 3 fm/s2/Hz in the 1 mHz≤f≤30 mHz band, slightly less than twice as large as the best performance reported with the baseline LISA Pathfinder configuration and below the current requirements for the Laser Interferometer Space Antenna mission.
46 citations
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TL;DR: In this article, the performance of the capacitive gap-sensing system of the Gravitational Reference Sensor on board the LISA Pathfinder spacecraft was reported, with a performance of up to 1mHz.
Abstract: We report on the performance of the capacitive gap-sensing system of the Gravitational Reference Sensor on board the LISA Pathfinder spacecraft From in-flight measurements, the system has demonstrated a performance, down to 1 mHz, that is ranging between 07 and 18 aF Hz-1/2 That translates into a sensing noise of the test mass motion within 12 and 24 nm Hz-1/2 in displacement and within 83 and 170 nrad Hz-1/2 in rotation This matches the performance goals for LISA Pathfinder, and it allows the successful implementation of the gravitational waves observatory LISA A 1/f tail has been observed for frequencies below 1 mHz, the tail has been investigated in detail with dedicated in-flight measurements, and a model is presented in the paper A projection of such noise to frequencies below 01 mHz shows that an improvement of performance at those frequencies is desirable for the next generation of gravitational reference sensors for space-borne gravitational waves observation
39 citations
Cited by
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TL;DR: In this article, the authors review early universe sources that can lead to cosmological backgrounds of GWs and discuss the basic characteristics of present and future GW detectors, including advanced LIGO, advanced Virgo, the Einstein telescope, KAGRA, and LISA.
Abstract: Gravitational waves (GWs) have a great potential to probe cosmology. We review early universe sources that can lead to cosmological backgrounds of GWs. We begin by presenting proper definitions of GWs in flat space-time and in a cosmological setting (section 2). Following, we discuss the reasons why early universe GW backgrounds are of a stochastic nature, and describe the general properties of a stochastic background (section 3). We recap current observational constraints on stochastic backgrounds, and discuss the basic characteristics of present and future GW detectors, including advanced LIGO, advanced Virgo, the Einstein telescope, KAGRA, and LISA (section 4). We then review in detail early universe GW generation mechanisms, as well as the properties of the GW backgrounds they give rise to. We classify the backgrounds in five categories: GWs from quantum vacuum fluctuations during standard slow-roll inflation (section 5), GWs from processes that operate within extensions of the standard inflationary paradigm (section 6), GWs from post-inflationary preheating and related non-perturbative phenomena (section 7), GWs from first order phase transitions related or not to the electroweak symmetry breaking (section 8), and GWs from general topological defects, and from cosmic strings in particular (section 9). The phenomenology of these early universe processes is extremely rich, and some of the GW backgrounds they generate can be within the reach of near-future GW detectors. A future detection of any of these backgrounds will provide crucial information on the underlying high energy theory describing the early universe, probing energy scales well beyond the reach of particle accelerators.
643 citations
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TL;DR: In this paper, the LISA space-based interferometer was used to detect the stochastic gravitational wave background produced from different mechanisms during inflation, focusing on well-motivated scenarios.
Abstract: We investigate the potential for the LISA space-based interferometer to detect the stochastic gravitational wave background produced from different mechanisms during inflation. Focusing on well-motivated scenarios, we study the resulting contributions from particle production during inflation, inflationary spectator fields with varying speed of sound, effective field theories of inflation with specific patterns of symmetry breaking and models leading to the formation of primordial black holes. The projected sensitivities of LISA are used in a model-independent way for various detector designs and configurations. We demonstrate that LISA is able to probe these well-motivated inflationary scenarios beyond the irreducible vacuum tensor modes expected from any inflationary background.
418 citations
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TL;DR: The MICROSCOPE satellite aims to test its validity at the 10^{-15} precision level, by measuring the force required to maintain two test masses exactly in the same orbit, by characterizing the relative difference in their free-fall accelerations.
Abstract: According to the weak equivalence principle, all bodies should fall at the same rate in a gravitational field. The MICROSCOPE satellite, launched in April 2016, aims to test its validity at the 10−15 precision level, by measuring the force required to maintain two test masses (of titanium and platinum alloys) exactly in the same orbit.
A nonvanishing result would correspond to a violation of the equivalence principle, or to the discovery of a new long-range force. Analysis of the first data gives δ(Ti; Pt)=[-1+/-9(stat)+/-9(syst)] × 10−15 (1σ statistical uncertainty) for the titanium-platinum Eotvos parameter characterizing the relative difference in their free-fall accelerations.
321 citations
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TL;DR: The article considers both Bayesian and frequentist searches using ground-based and space-based laser interferometers, spacecraft Doppler tracking, and pulsar timing arrays; and it allows for anisotropy, non-Gaussianity, and non-standard polarization states.
Abstract: We review detection methods that are currently in use or have been proposed to search for a stochastic background of gravitational radiation. We consider both Bayesian and frequentist searches using ground-based and space-based laser interferometers, spacecraft Doppler tracking, and pulsar timing arrays; and we allow for anisotropy, non-Gaussianity, and non-standard polarization states. Our focus is on relevant data analysis issues, and not on the particular astrophysical or early Universe sources that might give rise to such backgrounds. We provide a unified treatment of these searches at the level of detector response functions, detection sensitivity curves, and, more generally, at the level of the likelihood function, since the choice of signal and noise models and prior probability distributions are actually what define the search. Pedagogical examples are given whenever possible to compare and contrast different approaches. We have tried to make the article as self-contained and comprehensive as possible, targeting graduate students and new researchers looking to enter this field.
306 citations