|   | 
Credit & Copyright: Fermi National Accelerator Laboratory;  
 Photographer:  Reidar Hahn  
 
Explanation:
How fast do   
elementary particles wobble?    
  
A surprising answer to this seemingly   
inconsequential question came out of   
Brookhaven National Laboratory in   
New York,   
USA in 2001, and indicated that the   
Standard Model of Particle Physics, adopted widely in physics,  
is incomplete.  
  
Specifically, the   
muon, a particle with similarities to a heavy   
electron,   
has had its relatively large wobble   
under scrutiny in a series of experiments known as   
g-2 (gee-minus-two).  
  
The Brookhaven result galvanized other experimental groups   
around the world to confirm it, and pressured theorists   
to better understand it.    
  
Reporting in last week, the most sensitive   
muon wobble experiment yet,   
conducted at   
Fermi National Accelerator Laboratory   
(Fermilab) in Illinois and   
pictured here,   
agreed with the Brookhaven result.  
  
The unexpected  
wobble rate may   
indicate that an ever-present sea of    
virtual particles includes types not currently known.   
  
Alternatively, it   
may indicate that flaws exist in   
difficult theoretical prediction   
calculations.  
  
Future runs at   
Fermilab's g-2 experiment will further   
increase precision and, possibly, the statistical difference between the   
universe we measure and the   
universe we understand.  
  
  
| January February March April May June July August September October November December | 
 | ||||||||||||||||||||||||||||||||||||||||||||||||
NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.
Based on Astronomy Picture
Of the Day
Publications with keywords: particle physics
Publications with words: particle physics
See also:
