A5028115327- Geophysics and Sensor Technology
- Seismic Waves and Analysis
- Advanced Fiber Laser Technologies
- Advanced Fiber Optic Sensors
- Geophysics and Gravity Measurements
- Advanced Frequency and Time Standards
- High-pressure geophysics and materials
- Inertial Sensor and Navigation
- Seismic Imaging and Inversion Techniques
- Laser Design and Applications
- Seismology and Earthquake Studies
- earthquake and tectonic studies
- Astronomical Observations and Instrumentation
- Hydraulic Fracturing and Reservoir Analysis
- Geophysical and Geoelectrical Methods
- Reservoir Engineering and Simulation Methods
- Drilling and Well Engineering
- Solid State Laser Technologies
- GNSS positioning and interference
- Merger and Competition Analysis
- Advanced Measurement and Metrology Techniques
- Soil Moisture and Remote Sensing
- Historical Geography and Cartography
- Railway Engineering and Dynamics
- EU Law and Policy Analysis
Federal Agency for Cartography and Geodesy
2017-2023
Technical University of Munich
2012-2022
Ludwig-Maximilians-Universität München
2017-2021
GFZ Helmholtz Centre for Geosciences
2010
Friedrich Schiller University Jena
2007-2009
Ifo Institute for Economic Research
2005
We propose an under-ground experiment to detect the general relativistic effects due curvature of space-time around Earth (de Sitter effect) and rotation planet (dragging inertial frames or Lense-Thirring effect). It is based on comparison between IERS value vector corresponding measurements obtained by a tri-axial laser detector rotation. The proposed consists six large ring-lasers arranged along three orthogonal axes. In about two years data taking, 1% sensitivity required for measurement...
We demonstrate a $16\text{ }\text{ }{\mathrm{m}}^{2}$ helium-neon ring laser gyroscope with sufficient sensitivity and stability to directly detect the Chandler wobble of rotating Earth. The successful detection both annual is verified by comparing time series measurements against ``C04 series'' Earth rotation data from International Rotation Reference System Service.
Abstract Using a colocated ring laser and an STS‐2 seismograph, we estimate the ratio of Rayleigh‐to‐Love waves in secondary microseism at Wettzell, Germany, for frequencies between 0.13 0.30 Hz. Rayleigh wave surface acceleration was derived from vertical component STS‐2, Love laser. Surface amplitudes are comparable; near spectral peak about 0.22 Hz, 20% higher than amplitudes, but outside this range, become higher. In terms kinetic energy, energy is 20–35% smaller on average energy. The...
Absolute rotation rate sensing with extreme sensitivity requires a combination of several large scale gyroscopes in order to obtain the full vector rotation. We report on construction and operation four-component, tetrahedral laser gyroscope array as five story building situated near surface, underground laboratory. It is demonstrated that reconstruction Earth can be achieved sub-arcsecond resolution over more than six weeks.Received 3 February 2020Accepted 18 June...
SUMMARY Single-component ring lasers have provided high-resolution observations of Earth’s rotation rate as well local earthquake- or otherwise-induced rotational ground motions. Here, we present the design, construction and operational aspects ROMY, a four-component, tetrahedral-shaped laser installed at Geophysical Observatory Fürstenfeldbruck near Munich, Germany. Four equilateral, triangular-shaped with 12 m side length provide motions that can be combined to construct complete vector...
The validation of compatibility and long-term stability absolute gravimeters is a key component for the realization International Terrestrial Gravity Reference Frame (ITGRF) IAG relevant metrology, in particular kilogram. Because natural reference value gravity acceleration not accessible, international comparisons are well established. realized based on set accurate measurements functional model their processing. After CCM.G-K2.2023 comparison supplemented by additional ICAG-2023...
Classically, the scale factor of superconducting gravimeters (SGs) can be determined by two approaches. A first estimate obtained comparison its observations with a theoretical Earth tide and precise ocean loading models, after correcting for effects polar motion atmosphere on gravity. However, an independent estimation from existing models is preferred achieved through combination parallel absolute gravity observations, usually performed classical free-fall gravimeters. In this case, are...
Quantum gravimeters have been in use as laboratory instruments by various research groups for some time and available user-friendly commercial devices since 2014. In contrast to traditional absolute such the FG5, which employ corner cubes a falling test mass, these utilise laser-cooled cold-atom clouds. The Absolute Gravimeter (AQG) produced French company Exail is two model series: indoor observatory (A-series) outdoor capable (B-series).In this contribution, we present results of world's...
Research Article| May 24, 2017 Comparing Direct Observation of Strain, Rotation, and Displacement with Array Estimates at Piñon Flat Observatory, California Stefanie Donner; Donner aDepartment Earth Environmental Sciences, Ludwig Maximilian University Munich, Theresienstraße 41, 80333 Germany, donner@geophysik.uni-muenchen.delin@geophysik.uni-muenchen.dehadzii@geophysik.uni-muenchen.degebauer@geophysik.uni-muenchen.deigel@geophysik.uni-muenchen.dejowa@geophysik.uni-muenchen.de Search for...
GINGERino is a large frame laser gyroscope investigating the ground motion in most inner part of underground international laboratory Gran Sasso, central Italy. It consists square ring with 3.6 m side. Several days continuous measurements have been collected, apparatus running unattended. The power spectral density seismic bandwidth at level 10−10 (rad/s)/Hz. A maximum resolution 30 prad/s obtained an integration time few hundred seconds. routinely detects rotations induced by both regional...
Large ring lasers have exceeded the performance of navigational gyroscopes by several orders magnitude and become useful tools for geodesy. In order to apply them tests in fundamental physics, remaining systematic errors be significantly reduced. We derive a modified expression Sagnac frequency square laser gyro under Earth rotation. The modifications include corrections dispersion (of both gain medium mirrors), Goos-Hänchen effect mirrors, refractive index gas filling cavity. were measured...
During the past decades, research into fluid‐controlled geodynamic processes in upper crust of Earth is put foreward regarding stress accumulation, deformation, and seismicity. In a large‐scale injection experiment at deep borehole site KTB (Kontinentale Tiefbohrung der Bundesrepublik Deutschland) Germany, more than 84.000 m 3 fresh water was injected 4000 depth over 10 months, lot geoscientific investigations were connected to this test. The pore‐pressure change MPa yielded an induced which...
Large scale square ring laser gyros with a length of four meters on each side are approaching sensitivity 1x10^-11 rad/s/sqrt(Hz). This is about the regime required to measure gravitomagnetic effect (Lense Thirring) Earth. For an ensemble linearly independent measurement signal depends upon orientation single axis gyro respect rotational Therefore at least 3 necessary reconstruct complete angular apparatus. In general, setup consists several gyroscopes (we would prefer more than for...
We report on the frequency locking of a 16 m2 ring laser to single tooth an optical comb referenced hydrogen maser, obtaining stability 1 kHz over several days. In common mode operation, where counterpropagating beams run same longitudinal index, sensitivity rotation 3×10−9 relative Earth's is obtained. To test proposal bypass time-varying backscatter-induced readout errors in large gyroscopes, we have operated adjacent cavity modes. The Sagnac due obtained this fashion was strongly...
Abstract Monthly variations in the ratio of Rayleigh‐to‐Love waves secondary microseism are obtained from a colocated ring laser and an STS‐2 seismograph at Wettzell, Germany. Two main conclusions derived for wave kinetic energy ratios microseism; first, is range 0.8–0.9 (<1.0) throughout year except June July. It means that Love larger than Rayleigh most by about 10–20%. Second, this suddenly increases to 1.0–1.2 July, indicating fraction energy. This change suggests locations behaviors...
A 16 m(2) helium-neon-based ring laser gyroscope has been frequency stabilized to within 60 kHz over a period of three months. This is achieved using the beat and an iodine-stabilized reference as feedback signal on pressure vessel enclosing entire laser, under servo control. We demonstrate that we can compensate for, thereby negate influence of, atmospheric variations, which are considerable sources long-term instability.
Strain- and tiltmeter observations are composed of signals different origin. Tides a well-known phenomenon that can be extracted from the time series by tidal analysis. Depending on location station, residuals, however, contain contributions magnitudes ocean loading, changes in atmospheric or hydrological anthropogenic induced tectonics. Reductions residual variations indispensable for extraction of, example pure tectonical signal. One challenges view reductions is to understand transfer...
A number of studies have been carried out in order to determine the magnitude effects originating from surroundings an observation site which influence seismometer records or deformation observations with tilt- strainmeters. The investigations generally comprise thermal, atmospheric, topographic, and cavity effects, as well ocean loading. Recently, these continued extended using Finite Element (FE) modeling.
Research Article| March 29, 2017 An Event Database for Rotational Seismology Johannes Salvermoser; Salvermoser aDepartment of Earth and Environmental Sciences, Ludwig‐Maximilians‐University Munich, Theresienstrasse 41, D‐80333 Germanyheiner.igel@lmu.de Search other works by this author on: GSW Google Scholar Céline Hadziioannou; Hadziioannou Sarah Hable; Hable Lion Krischer; Krischer Bryant Chow; Chow Catalina Ramos; Ramos bDeutsches GeoForschungszentrum GFZ, Section Geophysical Deep...
The Gross Ring G is a square ring laser gyroscope, built as monolithic Zerodur structure with 4 m length on all sides. It has demonstrated that large provides sensitivity high enough to measure the rotational rate of Earth precision ΔΩE < 10-8. possible show further improvement in accuracy could allow observation metric frame dragging, produced by rotating mass (Lense-Thirring effect), predicted General Relativity. Furthermore, it can provide local measurement near provided international...
We describe the construction and operation of a large ring laser whose beam paths enclose an area <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mn>6.25</mml:mn> <mml:mspace width="thickmathspace"/> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:msup> <mml:mi mathvariant="normal">m</mml:mi> </mml:mrow> <mml:mn>2</mml:mn> </mml:msup> </mml:math> . The gyroscopic performance this interferometer was determined using at wavelength 632.8 nm. cavity Q inferred to be...
In June 2003, a large scale injection experiment started at the Continental Deep Drilling site (KTB) in Germany. A tiltmeter array was installed which consisted of five high resolution borehole tiltmeters ASKANIA type, also equipped with three dimensional seismometers. For next 11months, 86000m3 were injected into KTB pilot 4000m deep. The average rate approximately 200l∕min. research objective to observe and analyze deformation caused by upper crust kilometer range. new data acquisition...