A5041812620- Radio Astronomy Observations and Technology
- Particle physics theoretical and experimental studies
- Particle Detector Development and Performance
- Antenna Design and Optimization
- Superconducting and THz Device Technology
- Radiation Detection and Scintillator Technologies
- High-Energy Particle Collisions Research
- Astrophysics and Cosmic Phenomena
- Isotope Analysis in Ecology
- Microwave Engineering and Waveguides
- Astro and Planetary Science
- Particle Accelerators and Free-Electron Lasers
- Quantum Chromodynamics and Particle Interactions
- Millimeter-Wave Propagation and Modeling
- Space Science and Extraterrestrial Life
- Stellar, planetary, and galactic studies
- Atmospheric Ozone and Climate
- Planetary Science and Exploration
- Radio Wave Propagation Studies
- Gamma-ray bursts and supernovae
- Particle accelerators and beam dynamics
- Galaxies: Formation, Evolution, Phenomena
- Muon and positron interactions and applications
- Soil Moisture and Remote Sensing
- Gyrotron and Vacuum Electronics Research
University of California, Berkeley
2021-2025
Arizona State University
2022
University of South Florida
2021
University of California, Davis
2002-2006
Institute for Nuclear Research and Nuclear Energy
2006
European Organization for Nuclear Research
2006
Brookhaven National Laboratory
1987
Abstract The precise characterization and mitigation of systematic effects is one the biggest roadblocks impeding detection fluctuations cosmological 21 cm signals. Missing data in radio experiments, often due to frequency interference (RFI), pose a particular challenge power spectrum analysis as this could lead ringing bright foreground modes Fourier space, heavily contaminating Here we show that problem missing becomes even more arduous presence effects. Using realistic numerical...
ABSTRACT Detection of the faint 21 cm line emission from Cosmic Dawn and Epoch Reionization will require not only exquisite control over instrumental calibration systematics to achieve necessary dynamic range observations but also validation analysis techniques demonstrate their statistical properties signal loss characteristics. A key ingredient in achieving this is ability perform high-fidelity simulations kinds data that are produced by large, many-element, radio interferometric arrays...
ABSTRACT Observations of 21 cm line from neutral hydrogen promise to be an exciting new probe astrophysics and cosmology during the Cosmic Dawn through Epoch Reionization (EoR) when dark energy accelerates expansion our Universe. At each these epochs, separating bright foregrounds cosmological signal is a primary challenge that requires exquisite calibration. In this paper, we present calibration method called nucal extends redundant-baseline calibration, allowing spectral variation in...
Interferometric experiments designed to detect the highly redshifted 21-cm signal from neutral hydrogen are producing increasingly stringent constraints on power spectrum, but some k-modes remain systematics-dominated. Mutual coupling is a major systematic that must be overcome in order signal, and simulations reproduce effects seen data can guide strategies for mitigating mutual coupling. In this paper, we analyse 12 nights of Hydrogen Epoch Reionization Array compare against include...
The 21 cm transition from neutral Hydrogen promises to be the best observational probe of Epoch Reionisation (EoR). This has led construction low-frequency radio interferometric arrays, such as Reionization Array (HERA), aimed at systematically mapping this emission for first time. Precision calibration, however, is a requirement in observations. Due spatial compactness HERA, array prone effects mutual coupling, which inevitably lead non-smooth calibration errors that contaminate data. When...
New radio telescope arrays offer unique opportunities for large-scale commensal SETI surveys. Ethernet-based architectures are allowing multiple users to access data simultaneously by means of multicast Ethernet subscriptions. Breakthrough Listen will take advantage this conducting a survey on the MeerKAT in South Africa. By subscribing raw voltage streams, be able beamform commensally anywhere within field view during primary science observations. The conducted with unprecedented speed...
Cross-correlating 21cm and Ly$\alpha$ intensity maps of the Epoch Reionization (EoR) promises to be a powerful tool for exploring properties first galaxies. Next-generation mapping experiments such as Hydrogen Array (HERA) SPHEREx will individually probe reionization through power spectra lines respectively, but limited by bright foregrounds instrumental systematics. these measurements could reduce systematics, potentially tightening constraints on inferred astrophysical parameters. In this...
Abstract The great comet C/1995 O1 (Hale–Bopp) presented a remarkable opportunity to study its long-term brightness over four years. We used 2240 observations published in the International Comet Quarterly from 17 observers during 1995 July 1999 September create secular lightcurve. In order account for observer differences, we present novel algorithm reduce scatter and increase precision lightcurve compiled many sources. It is implemented publicly available code, ICQSPLITTER, which uses...
Abstract We introduce CALibration AMITY ( calamity ), a precision bandpass calibration method for radio interferometry. can solve direction-independent gains with arbitrary frequency structure to the high required 21 cm cosmology minimal knowledge of foregrounds or antenna beams and does not require any degree redundancy (repeated identical measurements same baseline). have achieved this through two key innovations. First, we model on each baseline independently using flexible highly...
ABSTRACT The 21 cm transition from neutral Hydrogen promises to be the best observational probe of Epoch Reionization (EoR). This has led construction low-frequency radio interferometric arrays, such as Array (HERA), aimed at systematically mapping this emission for first time. Precision calibration, however, is a requirement in observations. Due spatial compactness HERA, array prone effects mutual coupling, which inevitably lead non-smooth calibration errors that contaminate data. When...
In this paper we present the features and expected performance of re-designed CMS simulation software, as well experience from migration process. Today, suite is based on two principal components - Geant4 detector toolkit new offline Framework Event Data Model. The chain includes event generation, simulation, digitization steps. With Geant4, employ full set electromagnetic hadronic physics processes detailed particle tracking in 4 Tesla magnetic field. provides "action demand" mechanisms, to...
Observations of 21\,cm line from neutral hydrogen promise to be an exciting new probe astrophysics and cosmology during the Cosmic Dawn through Epoch Reionization (EoR) when dark energy accelerates expansion Universe. At each these epochs, separating bright foregrounds cosmological signal is a primary challenge that requires exquisite calibration. In this paper, we present calibration method called \textsc{nucal} extends redundant-baseline calibration, allowing spectral variation in antenna...
The CMS object oriented Geant4-based program is used to simulate the complete central detector (over 1 million geometrical volumes) and forward systems such as Totem telescopes, Castor calorimeter, zero degree Roman pots, luminosity monitor. simulation utilizes full set of electromagnetic hadronic physics processes provided by Geant4 detailed particle tracking in 4 tesla magnetic field. Electromagnetic shower parameterization can be instead high-energy electrons positrons, allowing...
The long-term brightness evolution of the great comet C/1995 O1 (Hale-Bopp) presented a remarkable opportunity to study behavior its coma over four years. We used approximately 2200 total visual magnitudes published in International Comet Quarterly taken from 17 observers during period 1995 July - 1999 September create secular lightcurve. In order account for observer differences, we present novel algorithm reduce scatter and increase precision lightcurve compiled many sources. It is...
Presented are the main design features and performance results of cathode strip chambers (CSCs) for CMS Endcap Muon System. The six-plane structure these yields a spatial resolution about 80 /spl mu/m, essentially uniform independent width (up to 16 mm, which is unusually wide cathode-to-anode wire distance 5 mm). In addition, net one-tenth at hardware trigger level (300ns) obtained using simple network comparators. time achieved sim/4ns (RMS) that allows unambiguous tagging bunch crossing...
We introduce CALAMITY, a precision bandpass calibration method for radio interferometry. CALAMITY can solve direction independent gains with arbitrary frequency structure to the high required 21 cm cosmology minimal knowledge of foregrounds or antenna beams and does not require any degree redundancy (repeated identical measurements same baseline). have achieved this through two key innovations. Firstly, we model on each baseline independently using flexible highly efficient set basis...