Author
J. Reiche
Bio: J. Reiche is an academic researcher from Leibniz University of Hanover. The author has contributed to research in topics: Gravitational wave & Pathfinder. The author has an hindex of 10, co-authored 24 publications receiving 1080 citations.
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 eLISA mission as discussed by the authors is the first mission to study the entire universe with gravitational waves, and it will offer a wide view of a dynamic cosmos using gravitational waves as new and unique messengers to unveil The Gravitational Universe.
Abstract: The last century has seen enormous progress in our understanding of the Universe. We know the life cycles of stars, the structure of galaxies, the remnants of the big bang, and have a general understanding of how the Universe evolved. We have come remarkably far using electromagnetic radiation as our tool for observing the Universe. However, gravity is the engine behind many of the processes in the Universe, and much of its action is dark. Opening a gravitational window on the Universe will let us go further than any alternative. Gravity has its own messenger: Gravitational waves, ripples in the fabric of spacetime. They travel essentially undisturbed and let us peer deep into the formation of the first seed black holes, exploring redshifts as large as z ~ 20, prior to the epoch of cosmic re-ionisation. Exquisite and unprecedented measurements of black hole masses and spins will make it possible to trace the history of black holes across all stages of galaxy evolution, and at the same time constrain any deviation from the Kerr metric of General Relativity. eLISA will be the first ever mission to study the entire Universe with gravitational waves. eLISA is an all-sky monitor and will offer a wide view of a dynamic cosmos using gravitational waves as new and unique messengers to unveil The Gravitational Universe. It provides the closest ever view of the early processes at TeV energies, has guaranteed sources in the form of verification binaries in the Milky Way, and can probe the entire Universe, from its smallest scales around singularities and black holes, all the way to cosmological dimensions.
208 citations
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TL;DR: The Laser Ranging Interferometer (LRI) instrument on the GRACE Follow-On mission has provided the first laser interferometric range measurements between remote spacecraft, separated by approximately 220 km.
Abstract: The Laser Ranging Interferometer (LRI) instrument on the Gravity Recovery and Climate Experiment (GRACE) Follow-On mission has provided the first laser interferometric range measurements between remote spacecraft, separated by approximately 220 km. Autonomous controls that lock the laser frequency to a cavity reference and establish the 5 degrees of freedom two-way laser link between remote spacecraft succeeded on the first attempt. Active beam pointing based on differential wave front sensing compensates spacecraft attitude fluctuations. The LRI has operated continuously without breaks in phase tracking for more than 50 days, and has shown biased range measurements similar to the primary ranging instrument based on microwaves, but with much less noise at a level of 1 nm/sqrt[Hz] at Fourier frequencies above 100 mHz.
159 citations
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TL;DR: The LISA Pathfinder (LPF) mission as discussed by the authors is the first in-flight test of low frequency gravitational wave detection metrology, which was designed to simulate one arm of space-borne gravitational wave detectors by shrinking the million kilometer scale arm lengths down to a few tens of centimeters.
Abstract: Laser Interferometer Space Antenna (LISA) Pathfinder (formerly known as SMART-2) is a European Space Agency mission designed to pave the way for the joint ESA/NASA LISA mission by testing in flight the critical technologies required for space borne gravitational wave detection; it will put two test masses in a near-perfect gravitational free-fall and control and measure their motion with unprecedented accuracy. This is achieved through technology comprising inertial sensors, high precision laser metrology, drag-free control and an ultra precise micro-Newton propulsion system. LISA Pathfinder (LPF) essentially mimics one arm of space-borne gravitational wave detectors by shrinking the million kilometer scale armlengths down to a few tens of centimeters, giving up the sensitivity to gravitational waves, but keeping the measurement technology. The scientific objective of the LPF mission consists then of the first in-flight test of low frequency gravitational wave detection metrology.
43 citations
Cited by
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University of Lisbon1, University of Mississippi2, Institut d'Astrophysique de Paris3, Perimeter Institute for Theoretical Physics4, Sapienza University of Rome5, California Institute of Technology6, University of Cambridge7, Cornell University8, Max Planck Society9, Montana State University10, Princeton University11, University of Oxford12, McMaster University13, University of Aveiro14, University of Tübingen15, Naresuan University16, Rochester Institute of Technology17, University of Oldenburg18, Georgia Institute of Technology19, University of Illinois at Urbana–Champaign20, University of Florida21, University of Wisconsin–Milwaukee22, The Chinese University of Hong Kong23, Northwestern University24, Case Western Reserve University25, Sao Paulo State University26, Cardiff University27, Imperial College London28, Grand Valley State University29, Kyoto University30
TL;DR: In this article, a catalog of modified theories of gravity for which strong-field predictions have been computed and contrasted to Einstein's theory is presented, and the current understanding of the structure and dynamics of compact objects in these theories is summarized.
Abstract: One century after its formulation, Einstein's general relativity (GR) has made remarkable predictions and turned out to be compatible with all experimental tests. Most of these tests probe the theory in the weak-field regime, and there are theoretical and experimental reasons to believe that GR should be modified when gravitational fields are strong and spacetime curvature is large. The best astrophysical laboratories to probe strong-field gravity are black holes and neutron stars, whether isolated or in binary systems. We review the motivations to consider extensions of GR. We present a (necessarily incomplete) catalog of modified theories of gravity for which strong-field predictions have been computed and contrasted to Einstein's theory, and we summarize our current understanding of the structure and dynamics of compact objects in these theories. We discuss current bounds on modified gravity from binary pulsar and cosmological observations, and we highlight the potential of future gravitational wave measurements to inform us on the behavior of gravity in the strong-field regime.
1,066 citations
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TL;DR: Lang as discussed by the authors reviewed Lang's work in the Journal of Scientific Instruments (JSI) and Supplement No 1, 1951 Pp xvi + 388 + iii + 80 (London: Institute of Physics, 1951).
Abstract: Journal of Scientific Instruments Editor: Dr H R Lang Vol 28 and Supplement No 1, 1951 Pp xvi + 388 + iii + 80 (London: Institute of Physics, 1951) Bound, £3 12s; unbound, £3
725 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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TL;DR: In this paper, the merits of and differences between the various quantities used for parameterizing noise curves and characterizing gravitational-wave amplitudes are discussed, and plots that consistently compare different detectors are presented.
Abstract: There are several common conventions in use by the gravitational-wave community to describe the amplitude of sources and the sensitivity of detectors. These are frequently confused. We outline the merits of and differences between the various quantities used for parameterizing noise curves and characterizing gravitational-wave amplitudes. We conclude by producing plots that consistently compare different detectors. Similar figures can be generated on-line for general use at http://rhcole.com/apps/GWplotter.
582 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