Radio astronomy and the rise of high-energy astrophysics two anniversaries

This paper celebrates the 100th anniversary of the birth of Martin Ryle and the 50th anniversary of the discovery of pulsars by Jocelyn Bell and Antony Hewish. Ryle and Hewish received the 1974 Nobel Prize in Physics, the first in the area of astrophysics. Their interests strongly overlapped, one of the key papers on the practical implementation of the technique of aperture synthesis being co-authored by Ryle and Hewish. The discovery of pulsars and the roles played by Hewish and Bell are described. These key advances were at the heart of the dramatic rise of high-energy astrophysics in the 1960s and led to the realization that general relativity is central to the understanding of high-energy astrophysical phenomena.

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INTER-DIVISION IX-X-XI WORKING GROUP ASTRONOMY FROM THE MOON

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308025842 ◽

2008 ◽

Vol 4 (T27A) ◽

pp. 356-356

Author(s):

Sallie L. Baliunas ◽

Yoji Kondo ◽

Norio Kaifu ◽

Oddbjørn Engvold ◽

Norio Kaifu ◽

...

Keyword(s):

Radio Astronomy ◽

Working Group ◽

High Energy ◽

The Moon ◽

High Energy Astrophysics ◽

Infrared Techniques

During the period the Working Group had proposed and was granted renewed status by Division XI Space and High-Energy Astrophysics. Additionally the Working Group requested to be extended to Division IX Optical and Infrared Techniques, Division X Radio Astronomy, as well as Division XI.

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BEYOND GRAVITOELECTROMAGNETISM: CRITICAL SPEED IN GRAVITATIONAL MOTION

International Journal of Modern Physics D ◽

10.1142/s0218271805008121 ◽

2005 ◽

Vol 14 (12) ◽

pp. 2025-2037 ◽

Cited By ~ 15

Author(s):

BAHRAM MASHHOON

Keyword(s):

General Relativity ◽

Critical Speed ◽

Massive Particle ◽

High Energy ◽

High Energy Astrophysics ◽

Newtonian Gravitation ◽

Dynamics Of Particles

A null ray approaching a distant astronomical source appears to slow down, while a massive particle speeds up in accordance with Newtonian gravitation. The integration of these apparently incompatible aspects of motion in general relativity is due to the existence of a critical speed. The dynamics of particles moving faster than the critical speed could then be contrary to Newtonian expectations. Working within the framework of gravitoelectromagnetism, the implications of the existence of a critical speed are explored. The results are expected to be significant for high energy astrophysics.

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Historical Introduction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100077670 ◽

1977 ◽

Vol 35 ◽

pp. 2-5

Author(s):

R. D. Heidenreich

Keyword(s):

Electron Emission ◽

Secondary Electron ◽

Secondary Electron Emission ◽

50Th Anniversary ◽

Secondary Emission ◽

Wave Nature ◽

Nobel Prize In Physics ◽

Primary Electrons ◽

The U.S ◽

Mutual Agreement

This program has been organized by the EMSA to commensurate the 50th anniversary of the experimental verification of the wave nature of the electron. Davisson and Germer in the U.S. and Thomson and Reid in Britian accomplished this at about the same time. Their findings were published in Nature in 1927 by mutual agreement since their independent efforts had led to the same conclusion at about the same time. In 1937 Davisson and Thomson shared the Nobel Prize in physics for demonstrating the wave nature of the electron deduced in 1924 by Louis de Broglie.The Davisson experiments (1921-1927) were concerned with the angular distribution of secondary electron emission from nickel surfaces produced by 150 volt primary electrons. The motivation was the effect of secondary emission on the characteristics of vacuum tubes but significant deviations from the results expected for a corpuscular electron led to a diffraction interpretation suggested by Elasser in 1925.

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P20 phosphor on polyimide as a large area high-resolution transmission screen for slow scan CCD systems

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100136477 ◽

1995 ◽

Vol 53 ◽

pp. 20-21

Author(s):

C. C. Ahn ◽

S. Karnes ◽

M. Lvovsky ◽

C. M. Garland ◽

H. A. Atwater ◽

...

Keyword(s):

Mechanical Stability ◽

High Energy ◽

Practical Implementation ◽

Line Pair ◽

Modulation Transfer ◽

Large Area ◽

Ccd Imaging ◽

Transmission Electron ◽

The One ◽

Beam Broadening

The bane of CCD imaging systems for transmission electron microscopy at intermediate and high voltages has been their relatively poor modulation transfer function (MTF), or line pair resolution. The problem originates primarily with the phosphor screen. On the one hand, screens should be thick so that as many incident electrons as possible are converted to photons, yielding a high detective quantum efficiency(DQE). The MTF diminishes as a function of scintillator thickness however, and to some extent as a function of fluorescence within the scintillator substrates. Fan has noted that the use of a thin layer of phosphor beneath a self supporting 2μ, thick Al substrate might provide the most appropriate compromise for high DQE and MTF in transmission electron microcscopes which operate at higher voltages. Monte Carlo simulations of high energy electron trajectories reveal that only little beam broadening occurs within this thickness of Al film. Consequently, the MTF is limited predominantly by broadening within the thin phosphor underlayer. There are difficulties however, in the practical implementation of this design, associated mostly with the mechanical stability of the Al support film.

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General Relativity

10.1093/oso/9780198822158.001.0001 ◽

2019 ◽

Cited By ~ 1

Author(s):

Steven Carlip

Keyword(s):

General Relativity ◽

High Energy Physics ◽

Hamiltonian Formulation ◽

Experimental Tests ◽

High Energy ◽

Gravitational Energy ◽

Field Equations ◽

Physics First ◽

Condensed Matter Theory ◽

Introductory Textbooks

This work is a short textbook on general relativity and gravitation, aimed at readers with a broad range of interests in physics, from cosmology to gravitational radiation to high energy physics to condensed matter theory. It is an introductory text, but it has also been written as a jumping-off point for readers who plan to study more specialized topics. As a textbook, it is designed to be usable in a one-quarter course (about 25 hours of instruction), and should be suitable for both graduate students and advanced undergraduates. The pedagogical approach is “physics first”: readers move very quickly to the calculation of observational predictions, and only return to the mathematical foundations after the physics is established. The book is mathematically correct—even nonspecialists need to know some differential geometry to be able to read papers—but informal. In addition to the “standard” topics covered by most introductory textbooks, it contains short introductions to more advanced topics: for instance, why field equations are second order, how to treat gravitational energy, what is required for a Hamiltonian formulation of general relativity. A concluding chapter discusses directions for further study, from mathematical relativity to experimental tests to quantum gravity.

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UVscope and its application aboard the ASTRI-Horn telescope

Experimental Astronomy ◽

10.1007/s10686-021-09728-6 ◽

2021 ◽

Author(s):

Maria Concetta Maccarone ◽

Giovanni La Rosa ◽

Osvaldo Catalano ◽

Salvo Giarrusso ◽

Alberto Segreto ◽

...

Keyword(s):

Gamma Ray ◽

Single Photon ◽

Photon Counting ◽

Light Flux ◽

Cosmic Ray ◽

High Energy ◽

Wide Field ◽

High Energy Astrophysics ◽

Single Photon Counting ◽

Photon Counting Mode

AbstractUVscope is an instrument, based on a multi-pixel photon detector, developed to support experimental activities for high-energy astrophysics and cosmic ray research. The instrument, working in single photon counting mode, is designed to directly measure light flux in the wavelengths range 300-650 nm. The instrument can be used in a wide field of applications where the knowledge of the nocturnal environmental luminosity is required. Currently, one UVscope instrument is allocated onto the external structure of the ASTRI-Horn Cherenkov telescope devoted to the gamma-ray astronomy at very high energies. Being co-aligned with the ASTRI-Horn camera axis, UVscope can measure the diffuse emission of the night sky background simultaneously with the ASTRI-Horn camera, without any interference with the main telescope data taking procedures. UVscope is properly calibrated and it is used as an independent reference instrument for test and diagnostic of the novel ASTRI-Horn telescope.

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