A5038575908- Pulsars and Gravitational Waves Research
- Gamma-ray bursts and supernovae
- Geophysics and Gravity Measurements
- Astrophysical Phenomena and Observations
- Cosmology and Gravitation Theories
- Astrophysics and Cosmic Phenomena
- Geophysics and Sensor Technology
- Advanced Frequency and Time Standards
- Atomic and Subatomic Physics Research
- Astronomical Observations and Instrumentation
- High-pressure geophysics and materials
- Magnetic confinement fusion research
- Adaptive optics and wavefront sensing
- Radio Astronomy Observations and Technology
- Statistical and numerical algorithms
- Magneto-Optical Properties and Applications
- Seismic Waves and Analysis
- Optical properties and cooling technologies in crystalline materials
- Glass properties and applications
- Crystallization and Solubility Studies
- Black Holes and Theoretical Physics
- earthquake and tectonic studies
- Luminescence Properties of Advanced Materials
- Iron-based superconductors research
- Dark Matter and Cosmic Phenomena
Montclair State University
2017-2024
University of Florida
2008-2021
Culham Science Centre
2014
Durham University
2014
Worcester Polytechnic Institute
2006-2007
The advanced LIGO gravitational wave detectors are nearing their design sensitivity and should begin taking meaningful astrophysical data in the fall of 2015. These resonant optical interferometers will have unprecedented to strains caused by passing waves. input optics play a significant part allowing these devices reach such sensitivities. Residing between pre-stabilized laser main interferometer, subsystem is tasked with preparing beam for interferometry at sub-attometer level while...
The Heisenberg uncertainty principle dictates that the position and momentum of an object cannot be simultaneously measured with arbitrary precision, giving rise to apparent limitation known as standard quantum limit (SQL). Gravitational-wave detectors use photons continuously measure positions freely falling mirrors so are affected by SQL. We investigated performance Laser Interferometer Gravitational-Wave Observatory (LIGO) after experimental realization frequency-dependent squeezing...
The validity of the theory McCumber [Phys. Rev.136, A954-A957 (1964)] has been tested by applying it to a number ground-state transition in various rare-earth-doped glasses. Special attention was given those aspects experimental procedure that can lead systematic errors, such as reabsorption fluorescence and baseline subtraction uncertainties absorption measurements. To ensure consistency between measurements, we used same geometry for light collection measurement. With these procedures...
The detection of gravitational waves from compact binary mergers by LIGO has opened the era wave astronomy, revealing a previously hidden side cosmos.To maximize reach existing observatory facilities, we have designed new instrument able to detect at distances 5 times further away than possible with Advanced LIGO, or greater 100 event rate.Observations this will make dramatic steps toward understanding physics nearby universe, as well observing universe out cosmological black hole...
Precision measurements of space and time, like those made by the detectors Laser Interferometer Gravitational-wave Observatory (LIGO), are often confronted with fundamental limitations imposed quantum mechanics. The Heisenberg uncertainty principle dictates that position momentum an object cannot both be precisely measured, giving rise to apparent limitation called Standard Quantum Limit (SQL). Reducing noise below SQL in gravitational-wave detectors, where photons used continuously measure...
We present the design and performance of LIGO Input Optics subsystem as implemented for sixth science run interferometers. The Initial experienced thermal side effects when operating with 7 W input power. designed, built, improved versions Enhanced LIGO, an incremental upgrade to interferometers, designed 30 At four times power demonstrated including better optical isolation, less drift, minimal lensing, higher efficiency. success fosters confidence its ability perform well in Advanced LIGO.
Faraday isolators play a key role in the operation of large-scale gravitational-wave detectors. Second-generation interferometers such as Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo will use high-average-power cw lasers (up to 200 W) requiring specially designed that are immune effects resulting from laser beam absorption–degraded isolation ratio, thermal lensing, thermally induced steering. In this paper, we present comprehensive study specifically for...
We present an experimental demonstration of adaptive control modal properties optical beams. The is achieved via heat-induced photothermal actuation transmissive elements. apply the heat using four electrical heaters in thermal contact with element. system capable controlling both symmetrical and astigmatic aberrations providing a powerful means for situ correction high power laser systems. demonstrate tunable lens focusing varying from minus infinity to -10 m along two axes SF57 glass....
The reciprocity theory of McCumber [Phys. Rev. 136, A954 (1964)], which relates optical absorption and emission spectra between two energy level manifolds, was tested at temperatures down to 130K on the F3∕24→I9∕24 transition in Nd-doped glass. Deviations calculated measured were observed for below 230K Nd:silicate 170K Nd:fluorozirconate Below these temperatures, is skewed shorter wavelength longer wavelength. magnitude deviation depends ratio inhomogeneous linewidth thermal kBT.
A single chord two-color CO2/HeNe (10.6/0.633 μm) heterodyne laser interferometer has been designed to measure the line integral electron density along mid-plane of MAST Upgrade tokamak, with a typical error 1 × 10(18) m(-3) (∼2° phase error) at 4 MHz temporal resolution. To ensure this diagnostic system can be restored from any failures without stopping operations, it located outside machine area. The final design and initial testing system, including details optics, vibration isolation,...
A survey has been performed at a frequency of 81.5 Mc/s using the technique two-dimensional aerial synthesis. Two small aerials were constructed pointing North Pole and forming an East–West interferometer whose spacing could take all values up to maximum 3000 ft. The themselves not be steered in hour angle so observations are restricted region sky centred on having diameter 40°.
Transition metal dichalcogenides attract considerable attention due to a variety of interesting properties, including long-range magnetism in nanocrystals. Here we investigate the magnetic, thermal, and electrical properties an ${\mathrm{FeTe}}_{2}$ single crystal with iron vacancy defects. Magnetic measurements show paramagnetic state absence magnetic order low anisotropy susceptibility. Fe $3d$ orbitals are well hybridized, contributing bad resistivity. Observed thermal conductivity values...
We report on the design and performance of small optic suspensions developed to suppress seismic motion out-of-cavity optics in Input Optics subsystem Advanced LIGO interferometric gravitational wave detector. These compact single stage provide isolation all six degrees freedom optic, local sensing actuation three them, passive damping for other three.
Through combined measurements of broadband optical spectroscopy (10 meV to 6 eV), electrical resistivity, and Hall effect, the effects gamma ray irradiation on electronic properties gallium‐doped ZnO (GZO) thin films, deposited by ion plating direct‐current arc discharge, are investigated. A significant number at various discharge currents ( I D = 100–200 A) oxygen gas flow rates (OFR 0–25 sccm), exposed doses 15 30 kGy rays, studied. The results indicate strong resilience films irradiation:...
The authors perform optical, Raman, and M\"ossbauer spectroscopy measurements of the narrow-gap semiconductor FeGa${}_{3}$, along with DFT band structure vibrational frequencies calculation. results indicate that spectral weight below charge gap approximately 0.4 eV originates from impurities not correlation effects. Both infrared Raman lines are very narrow, so too lines, which implies a good crystallinity sample.