G. Bergmann
A5038418562- Pulsars and Gravitational Waves Research
- Gamma-ray bursts and supernovae
- Geophysics and Gravity Measurements
- Astrophysical Phenomena and Observations
- Cosmology and Gravitation Theories
- Geophysics and Sensor Technology
- Astrophysics and Cosmic Phenomena
- Seismic Waves and Analysis
- High-pressure geophysics and materials
- Statistical and numerical algorithms
- Advanced Frequency and Time Standards
- Radio Astronomy Observations and Technology
- Atomic and Subatomic Physics Research
- Astronomical Observations and Instrumentation
- Seismology and Earthquake Studies
- Mechanical and Optical Resonators
- Computational Physics and Python Applications
- Superconducting Materials and Applications
- Black Holes and Theoretical Physics
- Magnetic confinement fusion research
- Real-time simulation and control systems
- Microfluidic and Capillary Electrophoresis Applications
- Orbital Angular Momentum in Optics
- Advanced Measurement and Metrology Techniques
- Inertial Sensor and Navigation
Max Planck Institute for Gravitational Physics
2014-2024
Leibniz University Hannover
2012-2024
Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)
2024
Max Planck Society
2012-2016
Friedrich Schiller University Jena
2012-2013
Laser Zentrum Hannover
2010
University of Hull
2001
Boeing (Australia)
1973-1975
University of Stuttgart
1972
On September 14, 2015 at 09:50:45 UTC the two detectors of Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with peak strain 1.0×10(-21). It matches waveform predicted by general relativity for inspiral and merger pair black holes ringdown resulting single hole. was matched-filter signal-to-noise ratio 24 false alarm rate estimated be less than 1 event per 203,000 years,...
On August 17, 2017 at 12∶41:04 UTC the Advanced LIGO and Virgo gravitational-wave detectors made their first observation of a binary neutron star inspiral. The signal, GW170817, was detected with combined signal-to-noise ratio 32.4 false-alarm-rate estimate less than one per 8.0×10^{4} years. We infer component masses to be between 0.86 2.26 M_{⊙}, in agreement known stars. Restricting spins range inferred stars, we find 1.17-1.60 total mass system 2.74_{-0.01}^{+0.04}M_{⊙}. source localized...
We present the results from three gravitational-wave searches for coalescing compact binaries with component masses above <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mn>1</a:mn><a:mtext> </a:mtext><a:mtext> </a:mtext><a:msub><a:mrow><a:mi>M</a:mi></a:mrow><a:mrow><a:mo stretchy="false">⊙</a:mo></a:mrow></a:msub></a:mrow></a:math> during first and second observing runs of advanced detector network. During run (<d:math...
On 2017 August 17, the gravitational-wave event GW170817 was observed by Advanced LIGO and Virgo detectors, gamma-ray burst (GRB) GRB 170817A independently Fermi Gamma-ray Burst Monitor, Anticoincidence Shield for Spectrometer International Gamma-Ray Astrophysics Laboratory. The probability of near-simultaneous temporal spatial observation occurring chance is $5.0\times 10^{-8}$. We therefore confirm binary neutron star mergers as a progenitor short GRBs. association provides new insight...
The Advanced LIGO gravitational wave detectors are second generation instruments designed and built for the two observatories in Hanford, WA Livingston, LA. identical design, specialized versions of a Michelson interferometer with 4 km long arms. As initial LIGO, Fabry-Perot cavities used arms to increase interaction time wave, power recycling is effective laser power. Signal has been added improve frequency response. In most sensitive region around 100 Hz, design strain sensitivity factor...
We describe the observation of GW170104, a gravitational-wave signal produced by coalescence pair stellar-mass black holes. The was measured on January 4, 2017 at 10∶11:58.6 UTC twin advanced detectors Laser Interferometer Gravitational-Wave Observatory during their second observing run, with network signal-to-noise ratio 13 and false alarm rate less than 1 in 70 000 years. inferred component hole masses are 31.2_{-6.0}^{+8.4}M_{⊙} 19.4_{-5.9}^{+5.3}M_{⊙} (at 90% credible level). spins best...
On 17 August 2017, the LIGO and Virgo observatories made first direct detection of gravitational waves from coalescence a neutron star binary system. The this gravitational-wave signal, GW170817, offers novel opportunity to directly probe properties matter at extreme conditions found in interior these stars. initial, minimal-assumption analysis data placed constraints on tidal effects coalescing bodies, which were then translated radii. Here, we expand upon previous analyses by working under...
On August 14, 2017 at 10∶30:43 UTC, the Advanced Virgo detector and two LIGO detectors coherently observed a transient gravitational-wave signal produced by coalescence of stellar mass black holes, with false-alarm rate ≲1 in 27 000 years. The was three-detector network matched-filter signal-to-noise ratio 18. inferred masses initial holes are 30.5_{-3.0}^{+5.7}M_{⊙} 25.3_{-4.2}^{+2.8}M_{⊙} (at 90% credible level). luminosity distance source is 540_{-210}^{+130} Mpc, corresponding to...
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected gamma-ray burst (GRB 170817A) delay of $\sim$1.7 s respect to time. From gravitational-wave signal, source initially localized sky region 31 deg$^2$ at luminosity distance $40^{+8}_{-8}$ Mpc component masses consistent stars. were later...
The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion a compact-object binary in large-velocity, highly nonlinear regime, and witness final merger excitation uniquely relativistic modes gravitational field. We carry out several investigations determine whether is consistent with black-hole general relativity. find that remnant's mass spin, as determined from low-frequency (inspiral) high-frequency (postinspiral) phases signal, are mutually solution...
In 2009-2010, the Laser Interferometer Gravitational-wave Observa- tory (LIGO) operated together with international partners Virgo and GEO600 as a network to search for gravitational waves of astrophysical origin. The sensitiv- ity these detectors was limited by combination noise sources inherent instrumental design its environment, often localized in time or frequency, that couple into gravitational-wave readout. Here we review performance LIGO instruments during this epoch, work done...
On June 8, 2017 at 02:01:16.49 UTC, a gravitational-wave signal from the merger of two stellar-mass black holes was observed by Advanced LIGO detectors with network signal-to-noise ratio 13. This system is lightest hole binary so far observed, component masses $12^{+7}_{-2}\,M_\odot$ and $7^{+2}_{-2}\,M_\odot$ (90% credible intervals). These lie in range measured low-mass X-ray binaries, thus allowing us to compare detected through gravitational waves electromagnetic observations. The...
On August 17, 2017, the Advanced LIGO and Virgo gravitational-wave detectors observed a low-mass compact binary inspiral. The initial sky localization of source signal, GW170817, allowed electromagnetic observatories to identify NGC 4993 as host galaxy. In this work, we improve estimates binary's properties, including component masses, spins, tidal parameters, using known location, improved modeling, recalibrated data. We extend range frequencies considered down 23 Hz, compared 30 Hz in...
On May 21, 2019 at 03:02:29 UTC Advanced LIGO and Virgo observed a short duration gravitational-wave signal, GW190521, with three-detector network signal-to-noise ratio of 14.7, an estimated false-alarm rate 1 in 4900 yr using search sensitive to generic transients. If GW190521 is from quasicircular binary inspiral, then the detected signal consistent merger two black holes masses 85_{-14}^{+21} M_{⊙} 66_{-18}^{+17} (90% credible intervals). We infer that primary hole mass lies within gap...
The second-generation of gravitational-wave detectors are just starting operation, and have already yielding their first detections. Research is now concentrated on how to maximize the scientific potential astronomy. To support this effort, we present here design targets for a new generation detectors, which will be capable observing compact binary sources with high signal-to-noise ratio throughout Universe.
On September 14, 2015, the Laser Interferometer Gravitational-Wave Observatory (LIGO) detected a gravitational-wave transient (GW150914); we characterize properties of source and its parameters. The data around time event were analyzed coherently across LIGO network using suite accurate waveform models that describe gravitational waves from compact binary system in general relativity. GW150914 was produced by nearly equal mass black hole masses 36_{-4}^{+5}M_{⊙} 29_{-4}^{+4}M_{⊙}; for each...
The first observational run of the Advanced LIGO detectors, from September 12, 2015 to January 19, 2016, saw detections gravitational waves binary black hole mergers. In this paper we present full results a search for merger signals with total masses up $100 M_\odot$ and detailed implications our observations these systems. Our search, based on general-relativistic models wave systems, unambiguously identified two signals, GW150914 GW151226, significance greater than $5\sigma$ over observing...
We present results on the mass, spin, and redshift distributions with phenomenological population models using ten binary black hole mergers detected in first second observing runs completed by Advanced LIGO Virgo. constrain properties of (BBH) mass spectrum a range parameterizations BBH spin distributions. find that distribution more massive such binaries is well approximated no than 1% holes $45\,M_\odot$, power law index $\alpha = {1.3}^{+1.4}_{-1.7}$ (90% credibility). also show BBHs are...
The discovery of the gravitational-wave source GW150914 with Advanced LIGO detectors provides first observational evidence for existence binary black-hole systems that inspiral and merge within age Universe. Such mergers have been predicted in two main types formation models, involving isolated binaries galactic fields or dynamical interactions young old dense stellar environments. measured masses robustly demonstrate relatively "heavy" black holes ($\gtrsim 25\, M_\odot$) can form nature....
We report on the population of 47 compact binary mergers detected with a false-alarm rate 1/yr in second LIGO--Virgo Gravitational-Wave Transient Catalog, GWTC-2. observe several characteristics merging black hole (BBH) not discernible until now. First, we find that primary mass spectrum contains structure beyond power-law sharp high-mass cut-off; it is more consistent broken power law break at $39.7^{+20.3}_{-9.1}\,M_\odot$, or Gaussian feature peaking $33.1^{+4.0}_{-5.6}\,M_\odot$ (90\%...
The detection of gravitational waves by Advanced LIGO and Virgo provides an opportunity to test general relativity in a regime that is inaccessible traditional astronomical observations laboratory tests. We present four tests the consistency data with binary black hole waveforms predicted relativity. One subtracts best-fit waveform from checks residual detector noise. second low- high-frequency parts observed signals. third phenomenological deviations introduced model (including...
Following a major upgrade, the two advanced detectors of Laser Interferometer Gravitational-wave Observatory (LIGO) held their first observation run between September 2015 and January 2016. With strain sensitivity 10^{-23}/sqrt[Hz] at 100 Hz, product observable volume measurement time exceeded that all previous runs within 16 days coincident observation. On 14, 2015, Advanced LIGO observed transient gravitational-wave signal determined to be coalescence black holes [B. P. Abbott et al.,...