* Astronomy

Members Login
Username 
 
Password 
    Remember Me  
Home -> Astronomy News -> Astronomy News -> Advanced Thin Ionisation Calorimeter
Post Info TOPIC: Advanced Thin Ionisation Calorimeter
Blobrana


L

Posts: 131433
Date:
RE: Advanced Thin Ionisation Calorimeter
Permalink  
 

New data from two experiments -- one in space, one on a balloon floating above Antarctica -- hint at a tantalising detection of dark matter, the mysterious stuff comprising 85% of the universe's matter. The evidence is a reported excess of high-energy electrons and their antimatter counterparts, positrons, which could be created as dark matter particles annihilate or decay.
The signal from Fermi, the orbiting gamma-ray telescope, is subtle, whereas that claimed by the balloon-borne Advanced Thin Ionisation Calorimeter (ATIC) is much more pronounced. The differences are puzzling, but the findings -- according to some -- could herald the birth of a new age of dark matter exploration.

Read more

__________________
Blobrana


L

Posts: 131433
Date:
ATIC Electron Excess
Permalink  
 

Title: Cosmic Ray Proton Background Could Explain ATIC Electron Excess
Authors: A.R. Fazely, R.M. Gunasingha, S.V. Ter-Antonyan
(Version v2)

We show that the excess in the Galactic electron flux recently published by Chang, et al. (Nature, 20 Nov. 2008) can have a simple methodical origin due to a contribution from misidentified proton induced electron-like events in the ATIC detector. A subtraction of the cosmic ray proton component from the published ATIC electron flux eliminates this excess in the range of 300 to 800 GeV.

Read more  (56kb, PDF)

__________________
Blobrana


L

Posts: 131433
Date:
RE: Advanced Thin Ionisation Calorimeter
Permalink  
 

Title: Distinguishing Between Dark Matter and Pulsar Origins of the ATIC Electron Spectrum With Atmospheric Cherenkov Telescopes
Authors: Jeter Hall, Dan Hooper

Recent results from the Advanced Thin Ionisation Calorimeter (ATIC) balloon experiment have identified the presence of a spectral feature between approximately 300 and 800 GeV in the cosmic ray electron spectrum. This spectral feature appears to imply the existence of a local (within about 1 kpc) source of high energy electrons. Emission from a local pulsar and dark matter annihilations have each been put forth as possible origins of this signal. In this letter, we consider the sensitivity of ground based atmospheric Cherenkov telescopes to electrons and show that observatories such as HESS and VERITAS should be able to resolve this feature with sufficient precision to discriminate between the dark matter and pulsar hypotheses with considerably greater than 5 sigma significance, even for conservative assumptions regarding their performance. In addition, this feature provides an opportunity to perform an absolute calibration of the energy scale of ground based, gamma ray telescopes.

Read more (47kb, PDF)

__________________
Blobrana


L

Posts: 131433
Date:
Permalink  
 

A high-altitude balloon experiment above the Antarctic seems to have seen a possible signature of mysterious 'dark matter', similar to that spotted earlier this year by a European satellite.
The Advanced Thin Ionisation Calorimeter (ATIC), an experiment to search for charged particles from space, has spotted a surplus of high-energy electrons coming from somewhere in the cosmos.

Read more


__________________
Page 1 of 1  sorted by
 
Quick Reply

Please log in to post quick replies.
Home -> Astronomy News -> Astronomy News -> Advanced Thin Ionisation Calorimeter


Create your own FREE Forum
Report Abuse 		Powered by ActiveBoard