Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Milagro Observatory Detects Cosmic Ray Hot Spots

26.11.2008
The University of Maryland-led Milagro collaboration, comprised of scientists from 16 institutions across the United States, has discovered two nearby regions with an unexpected excess of cosmic rays.

This is the second finding of a source of galactic cosmic rays relatively near Earth announced in the past week. In the November 20 issue of the journal Nature, ATIC an international experiment lead by LSU scientists and conceived by a University of Maryland physicist announced finding an unexpected surplus of cosmic-ray electrons from an unidentified, but relatively close source.

"These two results may be due to the same, or different, astrophysical phenomenon, said Jordan Goodman, a University of Maryland professor of physics and principal investigator for Milagro. However, they both suggest the presence of high-energy particle acceleration in the vicinity of the earth. Our new findings [published in the November 24 issue of Physical Review Letters] point to general locations for the localized excesses of cosmic-ray protons observed with the Milagro observatory.

Cosmic rays are actually charged particles, including protons and electrons that are accelerated to high energies from sources both outside and inside our galaxy. It's unknown exactly what these sources are, but scientists theorize they may include supernovae -- massive stars that explode -- quasars or perhaps from other even more exotic, less-understood sources within the universe. Until recently, it was widely held that cosmic-ray particles came toward Earth uniformly from all directions. These new findings are the strongest indications yet that the distribution of cosmic rays is not so uniform.

When these high energy cosmic ray particles strike the Earth's atmosphere, a large cascade of secondary particles are created in an extensive "air shower.” The Milagro observatory -- located in a 60m x 80m x 8m covered pond in the Jemez Mountains near Los Alamos, New Mexico -- 'sees' cosmic rays by observing the energetic secondary particles that make it to the surface.

Jordan and his Milagro colleagues used the cosmic-ray observatory to peer into the sky above the northern hemisphere for nearly seven years starting in July 2000. The Milagro observatory is unique in that it monitors the entire sky above the northern hemisphere. Its design and field of view, made it possible for the observatory to record over 200 billion cosmic-ray collisions with the Earth's atmosphere.

This allowed researchers for the first time to see statistical peaks in the number of cosmic-ray events originating from relatively small regions of the sky. Milagro observed an excess of cosmic ray protons in an area above and to the right of Orion, near the constellation Taurus. The other hot spot is a comma-shaped region in the sky near the constellation Gemini.

"Whatever the source of the protons we observed with Milagro, their path to Earth is deflected by the magnetic field of the Milky Way so that we cannot directly tell exactly where they originate,” said Goodman. "And whether the regions of excess seen by Milagro actually point to a source of cosmic rays, or are the result of some other unknown nearby effect is an important question raised by our observations.”

Even more revelatory observations of cosmic rays and further help solving the mystery of the origin of cosmic rays may come in the form of a new observatory that Jordan and his fellow U.S. Milagro scientists have partnered with colleagues in Mexico to propose to the National Science Foundation. This second-generation experiment named the High Altitude Water Cherenkov experiment (HAWC) would be built at a high-altitude site in Mexico.

More about Milagro

The National Science Foundation (NSF) funded construction of the Milagro through the University of Maryland. Maryland and the Los Alamos National Laboratory are the lead research institutions in Milagro, joined by scientists from 14 other U.S. institutions. The observatory's work was funded by NSF, the US Department of Energy, Los Alamos National Laboratory, and the University of California. For more information on Milagro, visit the University of Maryland Milagro website: http://umdgrb.umd.edu/cosmic/milagro.html or contact Jordan Goodman, University of Maryland, 301-405-6033 (goodman@umdgrb.umd.edu) or Brenda Dingus, Los Alamos National Laboratory, (dingus@lanl.gov).

Latest results: "Discovery of localized regions of excess 10-TeV cosmic rays,” A. A. Abdo, B. Allen, et al., Physical Review Letters,

Explore the ATIC

The Advanced Thin Ionization Calorimeter (ATIC) is an investigation directed to resolving fundamental questions about the shape of the elemental differential energy spectra from the low energy region through the highest practical energies. This ATIC investigation takes advantage of the existing NASA long-duration balloon flight capability in Antarctica and/or the Northern Hemisphere (e.g. Fairbanks). More at: http://www.atic.umd.edu/atic.html

Latest ATIC results: "An excess of cosmic ray electrons at energies of 300–800 GeV,” J. Chang, J. H. Adams, et al., Nature 456, 362-365 (20 November 2008

UM Conceived Experiment Finds Mysterious Cosmic Radiation
http://www.newsdesk.umd.edu/scitech/release.cfm?ArticleID=1793

Lee Tune | Newswise Science News
Further information:
http://www.umd.edu
http://www.lanl.gov

More articles from Physics and Astronomy:

nachricht First Juno science results supported by University of Leicester's Jupiter 'forecast'
26.05.2017 | University of Leicester

nachricht Measured for the first time: Direction of light waves changed by quantum effect
24.05.2017 | Vienna University of Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>