Open Questions: High-Energy Cosmic Rays
Open Directory Project: Cosmic Rays
- Categorized and annotated links. A version of this
list is at
Google, with entries sorted in "page rank" order.
Galaxy: Cosmic Rays
- Categorized site directory. Entries usually include
Sites with general resources
Cosmic and Heliospheric Learning Center: Cosmic Rays
- NASA site dealing with cosmic rays in general.
Pierre Auger Observatory
- "An international facility to study the highest energy
cosmic rays." The Web site of this research facility includes
questions and answers about cosmic rays,
background information, and
(mostly to related research sites).
High Resolution Fly's Eye
- "The goal of the High Resolution Fly's Eye (HiRes) Experiment ...
is to measure the energy spectrum, the arrival direction, and the
composition of cosmic rays above 1018 eV."
Information provided by research team at Columbia University.
High Resolution Fly's Eye
- "The High Resolution Fly's Eye (HiRes) is an experiment
to study the highest energy cosmic rays to determine the energy,
direction, and chemical composition of the incident particle."
Information provided by research team in Utah.
AGASA (Akeno Giant Air Shower Array)
- Information about a cosmic-ray research facility operated
by the University of Tokyo. Includes descriptions of results
and list of publications.
Surveys, overviews, tutorials
- Article from
Cosmic Rays: Introduction
- Basic information on cosmic rays. Part of NASA's
Universe site. There is also a more
advanced level page on this topic.
- Single page presenting a general introduction to the field
of cosmic rays, as of 1996, by R. A. Mewaldt.
Ask a High-Energy Astronomer: Cosmic Rays
- Common questions, with answers, provided by NASA's
Ask a High-Energy Astronomer service.
Could the end be in sight for ultrahigh-energy cosmic rays?
- September 2002 article from
Physics World, by
Subir Sarkar. "Recent observations may indicate a cut-off in the
spectrum of ultrahigh-energy cosmic rays, which would imply that
they originate from cosmologically distant sources."
AMS hints at cosmic-ray mystery
- June 1999 news article from
Physics World about
a result from observations using the Alpha Magnetic
Spectrometer on the Space Shuttle that indicate no change in
number of low-energy protons in cosmic rays due to lattitude
changes in the strength of Earth's magnetic field.
New observatory to solve cosmic puzzle
- April 1999 news article from
Physics World about
finalization of plans to build a observatory to detect the most
energetic cosmic rays.
Cosmic rays: the puzzles continue
- August 1998 news article from
possible observation of cosmic rays having energy larger than the
supposed upper limit.
Catching No Rays
- Short April 2008 Scientific American article.
"Missing in action: ultraenergetic cosmic rays from the Virgo cluster."
The Cosmic Ray Riddle
Symmetry Magazine, March 2012
- Data from the world's most powerful particle colliders
should shed light on a 100-year-old astrophysics mystery,
but even they cannot explain the perplexing properties of
the universe's most energetic particles. Are ultra-high-energy
cosmic rays heavier than expected? Or did scientists inadvertently
discover a new type of physics?
Science News, February 28, 2009
- High-energy invaders from space could signal a nearby
pulsar, or perhaps dark matter.
- Showered in Mystery
Astronomy, January 2001, pp. 43-47
- New detectors are being deployed in order to gather more data
on very rare ultra-high-energy cosmic rays. The energy behind these
events is so high (1021 eV) that their source is not
known, and even the type (or types) of particle involved hasn't
- Rain of Fire
Reuven Ramaty; James C. Higdon; Richard E. Lingenfelter;
The Sciences, November-December 1999, pp. 24-29
- The origins of even normal (not necessarily high-energy) cosmic
rays are still mysterious. One possible origin is "superbubbles",
cavities in the interstellar medium created by the explosions
of many supernovae.
- Cosmic Rays, Nuclear Gamma Rays and the Origin of the Light
Reuven Ramaty, Benzion Kozlovsky, Richard Lingenfelter
Physics Today, April 1998, pp. 30-35
- Observations of the abundance of light elements in galactic
halo stars indicate that all but the most energetic cosmic rays
originate in supernova explosions.
- The Highest-Energy Cosmic Rays
Thomas O'Halloran, Pierre Sokolsky, Shigeru Yoshida
Physics Today, January 1998, pp. 31-37
- There are a few cosmic ray events involving particles having
more energy than seemingly possible. Questions of the origin and
mechanism of such high-energy cosmic rays are considered.
Cosmic Rays at the Energy Frontier
James W. Cronin, Thomas K. Gaisser, Simon P. Swordy
Scientific American, January 1997, pp. 44-49
- Observation of high-energy cosmic rays and theories of their
origin are discussed.
- Michael W. Friedlander -- A Thin Cosmic Rain: Particles from
Harvard University Press, 2000
- A large portion of Friedlander's book is the history of
research into cosmic rays and a discussion of how they are
studied. But one also finds a good survey of all the different
types of matter (and energy) that make up cosmic rays, and
what they can tell us about astrophysical processes. The
important question -- where cosmic rays in general, and the
most energetic in particular, come from -- is not neglected.
- Roger Clay, Bruce Dawson - Cosmic Bullets: High-Energy Particles
- The high-energy charged particles known as cosmic rays carry
a large amount of astrophysical information. This book surveys
the history of cosmic ray astronomy and explains the open
questions regarding the source of the highest-energy events,
including a possible connection with gamma ray bursts.
Copyright © 2002 by Charles Daney, All Rights Reserved