In-orbit performance of the laser interferometer of Taiji-1 experimental satellite

Taiji-1, which is the first experimental satellite for space gravitational wave detection in China, relies on key technologies which include the laser interferometer, the gravitational reference sensor (GRS), the micro-thruster and the satellite platform. Similarly to the Laser Interferometer Space Antenna (LISA) pathfinder, except for the science interferometer, the optical bench (OB) of Taiji-1 contains reference and test mass (TM) interferometers. Limited by the lower mechanical strength of the carrier rocket and by the orbit environment, the OB of Taiji-1 is made of invar steel and fused silica, and it is aimed to achieve a sensitivity of the order of 100[Formula: see text]pm/[Formula: see text]. The experimental results from in-orbit tests of Taiji-1 demonstrate that the interferometer can reach a sensitivity of 30[Formula: see text]pm/[Formula: see text] in the frequency range of 0.01–10[Formula: see text]Hz, which satisfies the requirements of Taiji-1 mission.

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The inertial reference sensor CAESAR for the laser interferometer space antenna mission

Classical and Quantum Gravity ◽

10.1088/0264-9381/13/11a/035 ◽

1996 ◽

Vol 13 (11A) ◽

pp. A259-A270 ◽

Cited By ~ 6

Author(s):

Pierre Touboul ◽

Manuel Rodrigues ◽

George M Le Clerc

Keyword(s):

Laser Interferometer ◽

Space Antenna ◽

Laser Interferometer Space Antenna ◽

Reference Sensor

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Time-delay interferometry

Living Reviews in Relativity ◽

10.1007/s41114-020-00029-6 ◽

2020 ◽

Vol 24 (1) ◽

Author(s):

Massimo Tinto ◽

Sanjeev V. Dhurandhar

Keyword(s):

Time Delay ◽

Laser Interferometer ◽

Laser Light ◽

Space Antenna ◽

Phase Measurements ◽

Laser Noise ◽

Future Space ◽

Laser Interferometer Space Antenna ◽

Overall Performance ◽

Mathematical Foundations

AbstractEqual-arm detectors of gravitational radiation allow phase measurements many orders of magnitude below the intrinsic phase stability of the laser injecting light into their arms. This is because the noise in the laser light is common to both arms, experiencing exactly the same delay, and thus cancels when it is differenced at the photo detector. In this situation, much lower level secondary noises then set the overall performance. If, however, the two arms have different lengths (as will necessarily be the case with space-borne interferometers), the laser noise experiences different delays in the two arms and will hence not directly cancel at the photo detector. To solve this problem, a technique involving heterodyne interferometry with unequal arm lengths and independent phase-difference readouts has been proposed. It relies on properly time-shifting and linearly combining independent Doppler measurements, and for this reason it has been called time-delay interferometry (TDI). This article provides an overview of the theory, mathematical foundations, and experimental aspects associated with the implementation of TDI. Although emphasis on the application of TDI to the Laser Interferometer Space Antenna mission appears throughout this article, TDI can be incorporated into the design of any future space-based mission aiming to search for gravitational waves via interferometric measurements. We have purposely left out all theoretical aspects that data analysts will need to account for when analyzing the TDI data combinations.

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Pulsar–black hole binaries as a window on quantum gravity

International Journal of Modern Physics D ◽

10.1142/s0218271817430040 ◽

2017 ◽

Vol 26 (12) ◽

pp. 1743004 ◽

Cited By ~ 1

Author(s):

John Estes ◽

Michael Kavic ◽

Matthew Lippert ◽

John H. Simonetti

Keyword(s):

Quantum Gravity ◽

Laser Interferometer ◽

Mean Square ◽

Mean Square Deviation ◽

Space Antenna ◽

Gravitational Effects ◽

Arrival Times ◽

Black Hole Binaries ◽

Laser Interferometer Space Antenna ◽

Square Kilometer Array

Pulsars (PSRs) are some of the most accurate clocks found in nature, while black holes (BHs) offer a unique arena for the study of quantum gravity. As such, PSR–BH binaries provide ideal astrophysical systems for detecting effects of quantum gravity. With the success of aLIGO and the advent of instruments like the Square Kilometer Array (SKA) and Evolved Laser Interferometer Space Antenna (eLISA), the prospects for discovery of such PSR–BH binaries are very promising. We argue that PSR–BH binaries can serve as ready-made testing grounds for proposed resolutions to the BH information paradox. We propose using timing signals from a PSR beam passing through the region near a BH event horizon as a probe of quantum gravitational effects. In particular, we demonstrate that fluctuations of the geometry outside a BH lead to an increase in the measured root-mean-square deviation of arrival times of PSR pulsar traveling near the horizon.

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