Highest energy cosmic rays are actually coming from within our owngalaxy, not from distant GRB's!

Dear Yousuf Khan:

On Aug 18, 1:00*pm, Yousuf Khan wrote:
On 8/17/2010 5:21 PM, dlzc wrote:

It makes sense, actually. *More massive cosmic rays
are going to be more likely to tunnel the heliosheath.

I don't think they've said any of them have any trouble
tunnelling the heliosheath. Just that the ones with the
highest energy levels might be coming from our own
galaxy.

Just extending based on what we know. The heliosheath boundary is a
region of slightly increased pressure, with essentially zero net
motion wrt the Sun. So it should privde some slight tendency to brake
singly charged nucleii, whereas heavier nucleii with smaller relative
charge per unit mass, shoudl be able to punch through. Like muons
compared to electrons.

This might give another coarse measure of the amount
of interstellar medium, or given that number by other
measurements, "pinpoint" the distance-to-source.

Well, the entire galaxy's magnetic field is probably the
additive magnetic fields of its constituent stars. So
when cosmic rays get near the Sun's heliosheath, it's
been powered up by all of the other stars, so it can
likely power through the individual magnetic field of
one lone star.

"Static" magnetic fields only change path. They don't alter the KE of
a particle, just the direction portion of its momentum (discounting
sudden accelerations, which will usually cause a *loss* of energy).

Still, this seems like a path for future investigation...

David A. Smith

On 8/18/10 3:20 PM, dlzc wrote:
Dear Sam Wormley:

On Aug 18, 1:11 pm, Sam wrote:
On 8/18/10 3:00 PM, Yousuf Khan wrote:
On 8/17/2010 5:21 PM, dlzc wrote:

It makes sense, actually. More massive cosmic rays
are going to be more likely to tunnel the heliosheath.

I don't think they've said any of them have any trouble
tunnelling the heliosheath. Just that the ones with the
highest energy levels might be coming from our own
galaxy.

This might give another coarse measure of the amount
of interstellar medium, or given that number by other
. measurements, "pinpoint" the distance-to-source.

Well, the entire galaxy's magnetic field is probably
the additive magnetic fields of its constituent stars.
So when cosmic rays get near the Sun's heliosheath,
it's been powered up by all of the other stars, so it
can likely power through the individual magnetic field
of one lone star.

Why are you making the assumption "power up" as
opposed to "power down"?

Since magnetic fields are conservative, they really shouldn't "power"
either way, just change path.

David A. Smith

Da... Thanks David!
-Sam

On Aug 18, 1:51*am, Yousuf Khan wrote:
On 8/18/2010 4:37 AM, Peter Webb wrote:



"Yousuf Khan" wrote in message
...
Cosmic accelerators discovered in our galaxy
"But earlier this year, physicists using the Pierre Auger Observatory
in Argentina, the world's largest cosmic ray observatory, published a
surprising discovery: Many of the energetic cosmic rays found in the
Milky Way are not actually protons but nuclei -- and the higher the
energy, the greater the nuclei-to-proton ratio."
http://www.sciencedaily.com/releases...51.htm?utm_sou....

The subject of your post asserts something completely different to the
body.

What do you find is conflicting? They both seem to say the same thing to me.

That most cosmic rays come from sources in our own galaxy is not
surprising. Where would you expect them come to from? Quasars? Our
galaxy has everything except quasars, but up to and including a super
massive black hole, and obviously most of our flux will be from
structures in the Milky Way.

Well, yes, quasars and other AGN's. That was what the theory used to be,
wasn't it? The article itself says that's what the theory used to be.

If they consist of compound particles which are unstable, the highest
energy cosmic rays should tend to have a higher percentage of
extra-galactic sources, as relativistic time dilation would mean that
more were "in range", so to speak.

But this finding says the highest energy cosmic rays are compound
particles, and they are coming from our own galaxy, not extra-galactic.

* * * * Yousuf Khan

Perhaps other galactic cosmic rays are just a little tired by the time
they get here. (all those 70 atom buckyballs getting in their way)

~ BG

On 18/08/2010 4:25 PM, dlzc wrote:
Dear Yousuf Khan:

On Aug 18, 1:00 pm, Yousuf wrote:
Well, the entire galaxy's magnetic field is probably the
additive magnetic fields of its constituent stars. So
when cosmic rays get near the Sun's heliosheath, it's
been powered up by all of the other stars, so it can
likely power through the individual magnetic field of
one lone star.

"Static" magnetic fields only change path. They don't alter the KE of
a particle, just the direction portion of its momentum (discounting
sudden accelerations, which will usually cause a *loss* of energy).

Still, this seems like a path for future investigation...

David A. Smith

Yeah, that's what I meant really. I wasn't really saying that the cosmic
rays are having their speed increased by the magnetic field, just
altered in direction, which is still a *velocity* change.

Yousuf Khan