Author
Michele Armano
Other affiliations: European Space Research and Technology Centre
Bio: Michele Armano is an academic researcher from European Space Agency. The author has contributed to research in topics: Pathfinder & Gravitational wave. The author has an hindex of 17, co-authored 62 publications receiving 1398 citations. Previous affiliations of Michele Armano include European Space Research and Technology Centre.
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
)
fm
s
−
2
/
√
Hz
above 2 mHz and
(
6
±
1
)
×
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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TL;DR: The LISA Pathfinder (LPF) is a science and technology demonstrator planned by the European Space Agency in view of the LISA mission as discussed by the authors, and the progress made in preparing its effective implementation in flight.
Abstract: LISA Pathfinder (LPF) is a science and technology demonstrator planned by the European Space Agency in view of the LISA mission. As a scientific payload, the LISA Technology Package on board LPF will be the most precise geodesics explorer flown as of today, both in terms of displacement and acceleration sensitivity. The challenges embodied by LPF make it a unique mission, paving the way towards the space-borne detection of gravitational waves with LISA. This paper summarizes the basics of LPF, and the progress made in preparing its effective implementation in flight. We hereby give an overview of the experiment philosophy and assumptions to carry on the measurement. We report on the mission plan and hardware design advances and on the progress on detailing measurements and operations. Some light will be shed on the related data processing algorithms. In particular, we show how to single out the acceleration noise from the spacecraft motion perturbations, how to account for dynamical deformation parameters distorting the measurement reference and how to decouple the actuation noise via parabolic free flight.
94 citations
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University of Trento1, European Space Agency2, Max Planck Society3, Paris Diderot University4, Dornier Flugzeugwerke5, Spanish National Research Council6, Autonomous University of Barcelona7, University of Birmingham8, University of Hertfordshire9, University of Glasgow10, ETH Zurich11, European Space Operations Centre12, Imperial College London13, University of Zurich14, Polytechnic University of Catalonia15, University of Florida16
TL;DR: The current status of the LISA Pathfinder mission is described, a precursor mission aimed at demonstrating key technologies for future space-based gravitational wave detectors, like LISA, and performance measurements and analysis of these flight components lead to an expected performance of theLISA Pathfinder which is a significant improvement over the mission requirements.
Abstract: In this paper, we describe the current status of the LISA Pathfinder mission, a precursor mission aimed at demonstrating key technologies for future space-based gravitational wave detectors, like LISA. Since much of the flight hardware has already been constructed and tested, we will show that performance measurements and analysis of these flight components lead to an expected performance of the LISA Pathfinder which is a significant improvement over the mission requirements, and which actually reaches the LISA requirements over the entire LISA Pathfinder measurement band.
74 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
Cited by
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01 Jan 2005
TL;DR: The Monthly Notices as mentioned in this paper is one of the three largest general primary astronomical research publications in the world, published by the Royal Astronomical Society (RAE), and it is the most widely cited journal in astronomy.
Abstract: Monthly Notices is one of the three largest general primary astronomical research publications. It is an international journal, published by the Royal Astronomical Society. This article 1 describes its publication policy and practice.
2,091 citations
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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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National Institutes of Natural Sciences, Japan1, National Institute of Information and Communications Technology2, Raman Research Institute3, Waseda University4, Osaka Institute of Technology5, Kyoto University6, Osaka City University7, Japan Aerospace Exploration Agency8, University of Electro-Communications9, Kindai University10, National Institute of Advanced Industrial Science and Technology11, Tokyo Institute of Technology12, Goddard Space Flight Center13, University of Tokyo14, Hiroshima University15, Ochanomizu University16, Liverpool John Moores University17, Nagoya University18, Nihon University19, Rikkyo University20, Tokyo Keizai University21, Yamanashi Eiwa College22, Rochester Institute of Technology23, Stanford University24, California Institute of Technology25, Hirosaki University26, Niigata University27, Tokai University28, Tohoku University29, Osaka University30, National Defense Academy of Japan31, University of Tübingen32, Hosei University33, University of Wisconsin–Milwaukee34, Tokyo University of Science35, University of Birmingham36
614 citations
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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