D. F. Cowen
A5022413032- Astrophysics and Cosmic Phenomena
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Particle physics theoretical and experimental studies
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Pulsars and Gravitational Waves Research
- Geophysics and Gravity Measurements
- Particle accelerators and beam dynamics
- Scientific Research and Discoveries
- Radiation Detection and Scintillator Technologies
- Particle Detector Development and Performance
- Computational Physics and Python Applications
- Radio Wave Propagation Studies
- Solar and Space Plasma Dynamics
- Atomic and Subatomic Physics Research
- Gyrotron and Vacuum Electronics Research
- Radio, Podcasts, and Digital Media
- Cosmology and Gravitation Theories
- Noncommutative and Quantum Gravity Theories
- Cryospheric studies and observations
- Astrophysical Phenomena and Observations
- Quantum Chromodynamics and Particle Interactions
- Astronomy and Astrophysical Research
Pennsylvania State University
2015-2024
Southern University and Agricultural and Mechanical College
2021-2024
University of Alaska Anchorage
2017-2024
Providence College
2017-2024
Clark Atlanta University
2017-2024
The University of Texas at Arlington
2021-2024
Lawrence Berkeley National Laboratory
2024
Chiba University
2017-2021
Uppsala University
2006-2021
University of Chicago
2021
The IceCube Neutrino Observatory is a cubic-kilometer-scale high-energy neutrino detector built into the ice at South Pole. Construction of IceCube, largest to date, was completed in 2011 and enabled discovery astrophysical neutrinos. We describe here design, production, calibration digital optical module (DOM), cable systems, computing hardware, our methodology for drilling deployment. also online triggering data filtering systems that select candidate cosmic ray events analysis. Due...
We have remotely mapped optical scattering and absorption in glacial ice at the South Pole for wavelengths between 313 560 nm depths 1100 2350 m. used pulsed continuous light sources embedded with AMANDA neutrino telescope, an array of more than six hundred photomultiplier tubes buried deep ice. At greater 1300 m, both coefficient absorptivity follow vertical variations concentration dust impurities, which are seen cores from other Antarctic sites track climatological changes. The varies by...
Evidence for an extraterrestrial flux of high-energy neutrinos has now been found in multiple searches with the IceCube detector. The first solid evidence was provided by a search neutrino events deposited energies TeV and interaction vertices inside instrumented volume. Recent analyses suggest that extends to lower is also visible throughgoing, νμ-induced tracks from Northern Hemisphere. Here, we combine results six different astrophysical maximum-likelihood analysis. combined event sample...
Since the recent detection of an astrophysical flux high energy neutrinos, question its origin has not yet fully been answered. Much what is known about this comes from a small event sample neutrino purity, good resolution, but large angular uncertainties. In searches for point-like sources, on other hand, best performance given by using statistics and reconstructions. Track-like muon events produced in interactions satisfy these requirements. We present here results sources with neutrinos...
Accurate measurement of neutrino energies is essential to many the scientific goals large-volume telescopes. The fundamental observable in such detectors Cherenkov light produced by transit through a medium charged particles created interactions. amount emitted proportional deposited energy, which approximately equal energy for νe and νμ charged-current interactions can be used set lower bound on measure spectra statistically other channels. Here we describe methods performance...
We present results from an analysis looking for dark matter annihilation in the Sun with IceCube neutrino telescope. Gravitationally trapped Sun's core can annihilate into Standard Model particles making a source of GeV neutrinos. is able to detect neutrinos energies >100 while its low-energy infill array DeepCore extends this >10 GeV. This uses data gathered austral winters between May 2011 and 2014, corresponding 532 days livetime when Sun, being below horizon, up-going events, easiest...
Abstract We present a measurement of the high-energy astrophysical muon–neutrino flux with IceCube Neutrino Observatory. The uses high-purity selection 650k neutrino-induced muon tracks from northern celestial hemisphere, corresponding to 9.5 yr experimental data. With respect previous publications, is improved by increased size event sample and extended model testing beyond simple power-law hypotheses. An updated treatment systematic uncertainties atmospheric background fluxes has been...
Abstract Active galactic nuclei (AGN) are promising candidate sources of high-energy astrophysical neutrinos, since they provide environments rich in matter and photon targets where cosmic-ray interactions may lead to the production gamma rays neutrinos. We searched for neutrino emission from AGN using Swift-BAT Spectroscopic Survey catalog hard X-ray 12 yr IceCube muon track data. First, upon performing a stacked search, no significant was found. Second, we neutrinos list 43 found an excess...
A measurement of the atmospheric muon neutrino energy spectrum from 100 GeV to 400 TeV was performed using a data sample about 18 000 up-going events in IceCube. Boosted decision trees were used for event selection reject misreconstructed muons and obtain events. Background contamination final is less than 1%. This first neutrinos up TeV, fundamental understanding impact this background on astrophysical observations with The measured consistent predictions...
The recent observation by the IceCube neutrino observatory of an astrophysical flux neutrinos represents "first light" in nascent field astronomy. observed diffuse seems to suggest a much larger level hadronic activity non-thermal universe than previously thought and suggests rich discovery potential for observatory. This document presents vision substantial expansion current detector, IceCube-Gen2, including aim instrumenting $10\,\mathrm{km}^3$ volume clear glacial ice at South Pole...
We report new limits on cosmic neutrino fluxes from the test flight of Antarctic Impulsive Transient Antenna (ANITA) experiment, which completed an 18.4 day a prototype long-duration balloon payload, called ANITA-lite, in early 2004. search for impulsive events that could be associated with ultrahigh energy interactions ice and derive constrain several models rule out long-standing -burst model.
A search for muon neutrinos from neutralino annihilations in the Sun has been performed with IceCube 22-string neutrino detector using data collected 104.3 days of live time 2007. No excess over expected atmospheric background observed. Upper limits have obtained on annihilation rate captured neutralinos and converted to weakly interacting massive particle (WIMP) proton cross sections WIMP masses range 250-5000 GeV. These results are most stringent date Sun.
We report on the measurement of all-particle cosmic ray energy spectrum with IceTop air shower array in range from 1.58 PeV to 1.26 EeV. The is surface component IceCube Neutrino Observatory at geographical South Pole. analysis was performed using only information IceTop. data used this work were taken June 1, 2010 May 13, 2011. During that period consisted 73 stations compared 81 its final configuration. measured exhibits a clear deviation single power law above knee around 4PeV and below...
We present a measurement of the atmospheric neutrino oscillation parameters using three years data from IceCube Neutrino Observatory. The DeepCore infill array in center enables detection and reconstruction neutrinos produced by interaction cosmic rays Earth's atmosphere at energies as low ∼5 GeV. That energy threshold permits measurements muon disappearance, over range baselines up to diameter Earth, probing same L/Eν long-baseline experiments but with substantially higher-energy neutrinos....
We present the results of time-integrated searches for astrophysical neutrino sources in both northern and southern skies. Data were collected using partially completed IceCube detector 40-string configuration recorded between 2008 April 5 2009 May 20, totaling 375.5 days livetime. An unbinned maximum likelihood ratio method is used to search signals. The data sample contains 36,900 events: 14,121 from sky, mostly muons induced by atmospheric neutrinos, 22,779 high-energy muons. analysis...
We present results on searches for point-like sources of neutrinos using four years IceCube data, including the first year data from completed 86-string detector. The total livetime combined dataset is 1,373 days. For an E$^{-2}$ spectrum median sensitivity at 90\% C.L. $\sim 10^{-12}$ TeV$^{-1}$cm$^{-2}$s$^{-1}$ energies between 1 TeV$-$1 PeV in northern sky and 10^{-11}$ 100 TeV $-$ southern sky. has improved both additional introduction reconstructions compared to previous publications....
We present an improved event-level likelihood formalism for including neutrino telescope data in global fits to new physics. derive limits on spin-dependent dark matter-proton scattering by employing the a re-analysis of from 79-string IceCube search matter annihilation Sun, explicit energy information each event. The analysis excludes number models weak-scale minimal supersymmetric standard model (MSSM) first time. This work is accompanied public release data, as well associated computer...
ABSTRACT The recent discovery of a diffuse cosmic neutrino flux extending up to PeV energies raises the question which astrophysical sources generate this signal. Blazars are one class extragalactic may produce such high-energy neutrinos. We present likelihood analysis searching for cumulative emission from blazars in 2nd Fermi -LAT AGN catalog (2LAC) using IceCube data set 2009-12, was optimized detection individual sources. In contrast those previous searches with IceCube, populations...
We present the results and methodology of a search for neutrinos produced in decay charged pions created interactions between protons gamma-rays during prompt emission 807 gamma-ray bursts (GRBs) over entire sky. This three-year is first IceCube shower-like Cherenkov light patterns from electron, muon, tau correlated with GRBs. detect five low-significance events These are consistent background expectation atmospheric muons neutrinos. The this combination those IceCube's four years searches...
Between 2009 May and 2010 May, the IceCube neutrino detector at South Pole recorded 32 billion muons generated in air showers produced by cosmic rays with a median energy of 20 TeV. With data set this size, it is possible to probe southern sky for per-mil anisotropy on all angular scales arrival direction distribution rays. Applying power spectrum analysis relative intensity map ray flux hemisphere, we show that not isotropic, but shows significant structure several scales. In addition...