S. D. Biller
A5052114060- Astrophysics and Cosmic Phenomena
- Dark Matter and Cosmic Phenomena
- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Gamma-ray bursts and supernovae
- Particle Detector Development and Performance
- Radiation Detection and Scintillator Technologies
- Radio Astronomy Observations and Technology
- Solar and Space Plasma Dynamics
- Atomic and Subatomic Physics Research
- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Astronomical Observations and Instrumentation
- Cosmology and Gravitation Theories
- Nuclear Physics and Applications
- History and Developments in Astronomy
- Astronomy and Astrophysical Research
- Computational Physics and Python Applications
- Pulsars and Gravitational Waves Research
- Geomagnetism and Paleomagnetism Studies
- Astrophysical Phenomena and Observations
- Noncommutative and Quantum Gravity Theories
- Nuclear physics research studies
- Medical Imaging Techniques and Applications
- Microfluidic and Capillary Electrophoresis Applications
University of Oxford
2016-2025
Campbell Collaboration
2014-2023
University of Leeds
1995-2003
University of California, Irvine
1987-2000
Princeton University
2000
National Research Council Canada
2000
University of Notre Dame
1991
Los Alamos National Laboratory
1991
University of Maryland, College Park
1991
Argonne National Laboratory
1991
Observations of neutral-current nu interactions on deuterium in the Sudbury Neutrino Observatory are reported. Using neutral current (NC), elastic scattering, and charged reactions assuming standard 8B shape, nu(e) component solar flux is phis(e) = 1.76(+0.05)(-0.05)(stat)(+0.09)(-0.09)(syst) x 10(6) cm(-2) s(-1) for a kinetic energy threshold 5 MeV. The non-nu(e) phi(mu)(tau) 3.41(+0.45)(-0.45)(stat)(+0.48)(-0.45)(syst) s(-1), 5.3sigma greater than zero, providing strong evidence flavor...
The Sudbury Neutrino Observatory (SNO) has measured day and night solar neutrino energy spectra rates. For charged current events, assuming an undistorted 8B spectrum, the minus rate is 14.0%+/-6.3%(+1.5%)(-1.4%) of average rate. If total flux active neutrinos additionally constrained to have no asymmetry, nu(e) asymmetry found be 7.0%+/-4.9%(+1.3%)(-1.2%). A global analysis in terms matter-enhanced oscillations two flavors strongly favors large mixing angle solution.
The Sudbury Neutrino Observatory has precisely determined the total active (nu(x)) 8B solar neutrino flux without assumptions about energy dependence of nu(e) survival probability. measurements were made with dissolved NaCl in heavy water to enhance sensitivity and signature for neutral-current interactions. is found be 5.21 +/- 0.27(stat)+/-0.38(syst) x 10(6) cm(-2) s(-1), agreement previous standard models. A global analysis these other reactor results yields Deltam(2)=7.1(+1.2)(-0.6)...
SNO+ is a large liquid scintillator-based experiment located 2km underground at SNOLAB, Sudbury, Canada. It reuses the Sudbury Neutrino Observatory detector, consisting of 12m diameter acrylic vessel which will be filled with about 780 tonnes ultra-pure scintillator. Designed as multipurpose neutrino experiment, primary goal search for neutrinoless double-beta decay (0$\nu\beta\beta$) 130Te. In Phase I, detector loaded 0.3% natural tellurium, corresponding to nearly 800 kg 130Te, an expected...
The detection of gamma rays energy greater than 300 GeV from the BL Lacertae object Mrk 501 demonstrates that extragalactic TeV emission is not unique to 421. During 66 hr observations between 1995 March and July we measured an average flux 8.1 ± 1.4 × 10-12 cm-2 s-1 above GeV, a only 20% 421 flux. new gamma-ray source has been reported by Compton Gamma Ray Observatory as emitter at lower energies. There evidence for variability on timescales days.
Results are reported from a joint analysis of Phase I and II data the Sudbury Neutrino Observatory. The effective electron kinetic energy threshold used is ${T}_{\mathrm{eff}}=3.5$ MeV, lowest yet achieved with water Cherenkov detector data. In units ${10}^{6}$ cm${}^{\ensuremath{-}2}$ ${\mathrm{s}}^{\ensuremath{-}1}$, total flux active-flavor neutrinos $^{8}\mathrm{B}$ decay in Sun measured using neutral current (NC) reaction on deuterons, no constraint neutrino spectrum, found to be...
We have used data from a TeV $\ensuremath{\gamma}$-ray flare associated with the active galaxy Markarian 421 to place bounds on possible energy dependence of speed light in context an effective quantum gravitational scale. Recent theoretical work suggests that such scale could be less than Planck mass and perhaps as low ${10}^{16}$ GeV. The limits derived here indicate this excess $6\ifmmode\times\else\texttimes\fi{}{10}^{16}$ GeV for at least one approach gravity D-brane string theory. To...
The spectrum of gamma rays from the Crab Nebula has been measured in energy range 500 GeV-8 TeV at Whipple Observatory by atmospheric Cerenkov technique. Two methods analysis that were used to derive spectra, order reduce chance calibration errors, gave good agreement, as did observations made with changed equipment several years apart. It is concluded stable and reliable spectra can now be range. represented this power-law fit, J = (3.20 ± 0.17 0.6) × 10-7 (E/1 TeV)-2.49±0.06±0.04 m-2 s-1...
We present the discovery of >350 GeV gamma-ray emission from BL Lacertae object 1ES 2344+514 with Whipple Observatory 10m telescope. This is third Lac detected at energies above 300 Gev, other two being Markarian 421 (Mrk 421) and Mrk501. These three active galactic nuclei are all X-ray selected have lowest known redshifts any objects currently identified. The evidence for derives primarily an apparent flare on December 20, 1995 when a 6 sigma excess was flux approximately 63% very high...
We report on the γ-ray variability of Mrk 421 at Eγ > 300 GeV during 1995 season, and concentrate results an intense multiwavelength observing campaign in period April 20 to May 5, which included >100 MeV γ-ray, X-ray, extreme-ultraviolet, optical, radio observations, some show evidence for correlated behavior. Rapid variations TeV light curve with doubling decay times ≲1 day require a compact emission region significant Doppler boosting. The data reveal that is best characterized by...
A measurement of the $^{8}\mathrm{B}$ solar neutrino flux has been made using a 69.2 kt-day dataset acquired with $\mathrm{SNO}+$ detector during its water commissioning phase. At energies above 6 MeV is an extremely pure sample elastic scattering events, owing primarily to detector's deep location, allowing accurate relatively little exposure. In that energy region best fit background rate $0.2{5}_{\ensuremath{-}0.07}^{+0.09}\text{ }\text{...
The SNO+ Collaboration reports the first evidence of reactor antineutrinos in a Cherenkov detector. nearest nuclear reactors are located 240 km away Ontario, Canada. This analysis uses events with energies lower than any previous large water Two analytical methods used to distinguish from background 190 days data and yield consistent for combined significance 3.5σ.
The direction of individual <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mmultiscripts><a:mrow><a:mi mathvariant="normal">B</a:mi></a:mrow><a:mprescripts/><a:none/><a:mrow><a:mn>8</a:mn></a:mrow></a:mmultiscripts></a:mrow></a:math> solar neutrinos has been reconstructed using the <d:math xmlns:d="http://www.w3.org/1998/Math/MathML" display="inline"><d:mrow><d:mi>SNO</d:mi><d:mo>+</d:mo></d:mrow></d:math> liquid scintillator detector. Prompt, directional...
Abstract The SNO $$+$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>+</mml:mo> </mml:math> collaboration reports its first spectral analysis of long-baseline reactor antineutrino oscillation using 114 tonne-years data. Fitting the neutrino probability to observed energy spectrum yields constraints on mass-squared difference $$\Delta m^2_{21}$$ <mml:mrow> <mml:mi>Δ</mml:mi> <mml:msubsup> <mml:mi>m</mml:mi> <mml:mn>21</mml:mn> <mml:mn>2</mml:mn> </mml:msubsup> </mml:mrow>...
The energy spectrum of Markarian 421 in flaring states has been measured from 0.3 to 10 TeV using both small and large zenith angle observations with the Whipple Observatory m imaging telescope. technique is useful for extending spectra high energies, extraction this discussed. resulting fitted reasonably well by a simple power law: J(E)=E−2.54 ± 0.03 0.10 photons m-1 s-1 TeV-1, where first set errors statistical second systematic. This contrast our recently reported 501, which over similar...
The energy spectrum of the active galactic nucleus Markarian 501 has been determined from 0.3 to 10 TeV with Whipple Observatory Cerenkov Imaging Telescope, by using both small zenith angle and large data taken between 1997 February 14 June 8. emission Mrk was unprecedentedly high, allowing a statistically accurate be derived. In contrast previously measured spectra, over this region is not well described simple power law. Instead, exhibits significant curvature can fitted parabolic...
view Abstract Citations (82) References (29) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Outburst of TeV Photons from Markarian 421 Kerrick, A. D. ; Akerlof, C. W. Biller, S. Buckley, J. H. Cawley, M. F. Chantell, Connaughton, V. Fegan, Fennell, Gaidos, Hillas, Lamb, R. Lewis, Meyer, I. McEnery, Mohanty, G. Quinn, Rovero, Rose, Schubnell, Sembroski, Urban, Watson, Weekes, T. West, Wilson, Zweerink, 421, an active galactic nucleus (AGN) the BL Lacertae...
A search has been made for sinusoidal periodic variations in the $^8$B solar neutrino flux using data collected by Sudbury Neutrino Observatory over a 4-year time interval. The variation at period of one year is consistent with modulation Earth's orbital eccentricity. No significant periodicities are found periods between 1 day and 10 years either an unbinned maximum likelihood analysis or Lomb-Scargle periodogram analysis. inconsistent hypothesis that results recent Sturrock et al., based...
Results are reported on the measurement of atmospheric neutrino-induced muon flux at a depth 2 kilometers below Earth's surface from 1229 days operation Sudbury Neutrino Observatory (SNO). By measuring through-going muons as function zenith angle, SNO experiment can distinguish between oscillated and unoscillated portion neutrino flux. A total 514 muonlike events measured $\ensuremath{-}1\ensuremath{\le}\mathrm{cos}{\ensuremath{\theta}}_{\mathrm{zenith}}\ensuremath{\le}0.4$ in exposure...
An approach to developing a feasible neutrinoless double beta decay experiment capable of probing Majorana masses in the regime nondegenerate normal neutrino mass hierarchy is proposed. For such an experiment, this study suggests that 130Te likely best choice candidate isotope and metal-loaded liquid scintillator represents detector technology. evaluation required loading, properties configuration presented. While further development Te-loaded required, recent progress area task may not be...