Featured Research

from universities, journals, and other organizations

Physicists Find Evidence For Highest Energy Photons Ever Detected From Milky Way's Equator

Date:
December 14, 2005
Source:
New York University
Summary:
Physicists at nearly a dozen research institutions, including New York University, have discovered evidence for very high energy gamma rays emitting from the Milky Way, marking the highest energies ever detected from the galactic equator. Their findings, published in the Dec. 16 issue of the Physical Review of Letters, were obtained using the Milagro Gamma Ray Observatory, a new detector located near Los Alamos, N.M., that allows monitoring of the northern sky on a 24-hour, 7-day-per-week basis.

Physicists at nearly a dozen research institutions, including New York University, have discovered evidence for very high energy gamma rays emitting from the Milky Way, marking the highest energies ever detected from the galactic equator. Their findings, published in the Dec. 16 issue of the Physical Review of Letters, were obtained using the Milagro Gamma Ray Observatory, a new detector located near Los Alamos, N.M., that allows monitoring of the northern sky on a 24-hour, 7-day-per-week basis.

Gamma rays are considered by scientists to be the best probe of cosmic rays outside the solar neighborhood.

The research team, which includes nearly 40 physicists, reported that Milagro, positioned at an altitude of 8600 feet in the Jemez Mountains, detected a signal along the galactic equator region and interpreted it as arising from gamma rays with a median energy of 3.5 trillion electron-volts, or 3500 times the mass-energy of a proton. Previous satellite experiments have seen gamma-ray emissions along the galactic equator reaching up to energies of only 30 billion electron-volts.

These emissions are understood to be produced by interactions of cosmic-ray particles with the abundant interstellar medium near the galactic equator. Previously, some researchers had speculated that additional mechanisms were needed to explain the large number of particles observed at high energies. However, the measurements by Milagro can be understood by assuming a cosmic ray energy spectrum near the galactic center similar to that in the solar system and the standard properties of particle interactions.

The results presented in the Physical Review of Letters paper were gathered over a three-year period, beginning in July 2000.

###

The NYU collaborators on this work included Roman Fleysher, whose Ph.D. thesis formed the basis of much of this work, his advisor, Professor Peter Nemethy, Roman's brother, Lazar, and NYU Physics Professor Allen Mincer. Roman's thesis work, which was based on 14 months of data, was later extended to the present analysis on three years of data. The Fleysher brothers are currently post-doctoral fellows with the MRI spectroscopy group lead by Professor Oded Gonen at the Department of Radiology, NYU School of Medicine.


Story Source:

The above story is based on materials provided by New York University. Note: Materials may be edited for content and length.


Cite This Page:

New York University. "Physicists Find Evidence For Highest Energy Photons Ever Detected From Milky Way's Equator." ScienceDaily. ScienceDaily, 14 December 2005. <www.sciencedaily.com/releases/2005/12/051214084255.htm>.
New York University. (2005, December 14). Physicists Find Evidence For Highest Energy Photons Ever Detected From Milky Way's Equator. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2005/12/051214084255.htm
New York University. "Physicists Find Evidence For Highest Energy Photons Ever Detected From Milky Way's Equator." ScienceDaily. www.sciencedaily.com/releases/2005/12/051214084255.htm (accessed July 28, 2014).

Share This




More Space & Time News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

This Week @ NASA, July 25, 2014

This Week @ NASA, July 25, 2014

NASA (July 25, 2014) Apollo 11 celebration, Next Giant Leap anticipation, ISS astronauts appear in the House and more... Video provided by NASA
Powered by NewsLook.com
Space to Ground: Coming and Going

Space to Ground: Coming and Going

NASA (July 25, 2014) One station cargo ship leaves, another arrives, aquatic research and commercial spinoffs. Questions or comments? Use #spacetoground to talk to us. Video provided by NASA
Powered by NewsLook.com
How A Solar Flare Could Have Wrecked Earth's Electronics

How A Solar Flare Could Have Wrecked Earth's Electronics

Newsy (July 25, 2014) Researchers say if Earth had been a week earlier in its orbit around the sun, it would have taken a direct hit from a 2012 coronal mass ejection. Video provided by Newsy
Powered by NewsLook.com
Raw: ISS Cargo Ship Launches in Kazakhstan

Raw: ISS Cargo Ship Launches in Kazakhstan

AP (July 23, 2014) The Progress 56 cargo ship launched from the Baikonur Cosmodrome in Kazakhstan Wednesday. NASA says it will deliver cargo and crew supplies to the International Space Station. (July 23) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins