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Backes, P.

Publications and source records attributed to Backes, P..

At least 37 records · Page 2

All-sky Measurement of the Anisotropy of Cosmic Rays at 10 TeV and Mapping of the Local Interstellar Magnetic Field

© 2019. The American Astronomical Society. All rights reserved. We present the first full-sky analysis of the cosmic ray arrival direction distribution with data collected by the High-Altitude Water Cherenkov and IceCube observatories in the northern and southern hemispheres at the same median primary particle energy of 10 TeV. The combined sky map and angular power spectrum largely eliminate biases that result from partial sky coverage and present a key to probe into the propagation properties of TeV cosmic rays through our local interstellar medium and the interaction between the interstellar and heliospheric magnetic fields. From the map, we determine the horizontal dipole components of the anisotropy δ 0h = 9.16 ×10 -4 and δ 6h = 7.25 ×10 -4 (±0.04 × 10 -4 ). In addition, we infer the direction (229.°2 ± 3.°5 R.A., 11.°4 ± 3.°0 decl.) of the interstellar magnetic field from the boundary between large-scale excess and deficit regions from which we estimate the missing corresponding vertical dipole component of the large-scale anisotropy to be δ N ~ -3.97 +1.0-2.0 × 10 -4 .

79 ASTRONOMY AND ASTROPHYSICS↗

Search for neutrinos from decaying dark matter with IceCube: IceCube Collaboration

With the observation of high-energy astrophysical neutrinos by the IceCube Neutrino Observatory, interest has risen in models of PeV-mass decaying dark matter particles to explain the observed flux. We present two dedicated experimental analyses to test this hypothesis. One analysis uses 6 years of IceCube data focusing on muon neutrino ‘track’ events from the Northern Hemisphere, while the second analysis uses 2 years of ‘cascade’ events from the full sky. Known background components and the hypothetical flux from unstable dark matter are fitted to the experimental data. Since no significant excess is observed in either analysis, lower limits on the lifetime of dark matter particles are derived: we obtain the strongest constraint to date, excluding lifetimes shorter than 10 28 s at 90% CL for dark matter masses above 10TeV.

79 ASTRONOMY AND ASTROPHYSICS↗

Differential limit on the extremely-high-energy cosmic neutrino flux in the presence of astrophysical background from nine years of IceCube data

We report a quasidifferential upper limit on the extremely-high-energy (EHE) neutrino flux above 5×10 6 GeV based on an analysis of nine years of IceCube data. The astrophysical neutrino flux measured by IceCube extends to PeV energies, and it is a background flux when searching for an independent signal flux at higher energies, such as the cosmogenic neutrino signal. We have developed a new method to place robust limits on the EHE neutrino flux in the presence of an astrophysical background, whose spectrum has yet to be understood with high precision at PeV energies. A distinct event with a deposited energy above 106 GeV was found in the new two-year sample, in addition to the one event previously found in the seven-year EHE neutrino search. These two events represent a neutrino flux that is incompatible with predictions for a cosmogenic neutrino flux and are considered to be an astrophysical background in the current study. The obtained limit is the most stringent to date in the energy range between 5×10 6 and 2×10 10 GeV. This result constrains neutrino models predicting a three-flavor neutrino flux of E$2\atop{ν}$φ ν$_e$ + ν$_μ$ + ν$_τ$ ≃2×10 -8 GeV/cm 2 sec sr at 10 9 GeV. Finally, a significant part of the parameter space for EHE neutrino production scenarios assuming a proton-dominated composition of ultra-high-energy cosmic rays is disfavored independently of uncertain models of the extragalactic background light which previous IceCube constraints partially relied on.

79 ASTRONOMY AND ASTROPHYSICS↗

Mono Lake Analog Mars Sample Return Expedition for AMASE

We explored the performance of one robotic prototype for sample acquisition and caching of martian materials that has been developed at the Jet Propulsion Laboratory for potential use in the proposed MAX-C Mars Sample Return architecture in an environment, rich in chemical diversity with a variety of mineralogical textures. Mono Lake State Tufa Reserve in Mono County, CA possesses a variety of minerals including a variety of evaporites, volcanic glass and lava, and sand and mudstones. The lake itself is an interesting chemical system: the water is highly alkaline (pH is approximately 10) and contains concentrations of Cl, K, B, with lesser amounts of S Ca Mg, F, As, Li, I and Wand generally enriched HREEs. There are also traces of radioactive elements U, Th, Pl.

Conrad, P. G.↗

PTEP: the Parallel Telemetry Processor

The Parallel Telemetry Processor (PTEP), a high-speed, robust, and extensible telemetry processing system is discussed in this paper.

downloading telemetry processing operations↗

An Operations System for a Planetary Rover Prototype

A distributed operations system, the Web Interface for Telescience (WITS), is being developed for use in future planetary lander and rover mission operations.

Ground operations manipulator control Internet pla↗

Internet Based Operations for the Mars Polar Lander Mission

The Mars Polar Lander (MPL) mission is the first planetary mission to use Internet-based distributed ground operations where scientists and engineers collaborate in daily mission operations from multiple geographically distributed locations via the Internet.

Mission↗

Mars Polar Lander Mission Distributed Operations

The Mars Polar Lander (MPL) mission is the first planetary mission to use Internet-based distributed ground operations where scientists and engineers collaborate in daily mission operations from multiple geographically distributed locations via the Internet.

ground operations minipulator control internet pla↗