Are there positrons in a cosmic wave that are not produced as secondaries?
Posted 14 May 2004 - 08:39 PM
The positron spectral index below 15 GeV is found to be about -3.1: this value is what you would expect for secondary production without invoking rigidity dependent storage times or radiative energy losses expected at these energies. The spectrum should be steepening in this region but scientists found out that they are actually flattening.
Are there positrons in a cosmic wave that are not produced as secondaries, and if they are indeed all secondary particles, at what point do the radiative losses become important?
Posted 14 May 2004 - 08:40 PM
What will happen if you aim a positron beam at a beam of electrons?
If positrons are positive and electrons are negative would you get a huge heating effect due to a very high friction between the 2colliding particles that travel at a spped of light(or close there anyways), and as a byproduct get a set of "molecules" consisteing of one electron and one positrone?
If friction is a force that wil create heat in this case, and force has to have mass and acceleration
F = m a
Posted 15 May 2004 - 09:56 AM
Well, I don't know much on this subject, but I found this page -
They are taking about "Positron emission and image reconstruction" for PET (Positron Emission Tomography) scanning. (used in cardiology, neurology and oncology)
Here it says-
"When a positron comes in contact with an electron, the two particles annihilate turning the mass of the two particles into two 511-keV gamma-rays that are emitted at 180-degree to each other."
I hope this helps.
Posted 17 May 2004 - 07:00 AM
Posted 17 May 2004 - 08:47 AM
I'm glad I could help.
quote - "it kind of makes sense, but is kind of strange at the same time..."
I know what you mean. For me, getting the concept of some things in physics, is like building sandcastles in the rain.
Posted 17 May 2004 - 06:19 PM