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The question is basically the same as - you can read up on that one quite well on Wikipedia - "Why do we observe charm quarks and bottom quarks in bound states such as the J/Psi or Bottomonium, but no Topponium?"
It's simple, really: We know about most of the matter that is common around here, which is matter that exists under the conditions that we have here.
Now, when we go ahead and try to create hitherto unknown forms of matter, we create extreme conditions not normally encountered around us. A way to do this that we understand fairly well is to create extreme pressures and extreme temperatures, as in RHIC collisions.
As it happens, those are the conditions inside collapsed stars, so when we discover new forms of matter this way, it's likely that it exist there, as well.
Your friendly neighborhood hopefully-soon-to-be astrophysicist
He shits you not!
Shed and outhouse are uncommon these days, but only a year back, I calculated stuff in femtobarns in my exam of Particle Physics.
Wouldn't an Anti-Strange Hypernuclei just be a Normal Hypernuclei?
"Strange", in this context, means "having the attribute of positive strangeness", which means that these hypernuclei are composed of at least one nucleon which, in turn, is composed of at least one strange quark (as opoosed to "ordinary" up and down quarks).
Thus, "anti-strange" means "having the attribute of negative strangeness", which stands for all the ablove blah-blah, but with "strange anti-quark" inserted instead of "strange quark".
Hypernuclei with negative strangeness haven't been "created for the first time". They've been produced in RHIC collisions for as long as they've been running (with sufficient energy), and it's only now that we've been able to see them.
That, however, is quite the accomplishment, as relativistic heavy ions collisions are so complex that we're hardly begun to understand what happens in them. Think a two-hundred-truck collision at 1,000 mph, and you're interested in what screw came from which truck and how the drivers' shoes were tied.
[No truck drivers were hurt in the writing of this comment!]
Now anyone think this story was posted just because the quark happens to be named "strange"?
Well, you certainly won't find Truth or Beauty here!
Well, it makes sense to someone familiar with accelerator design, but it's pretty redundant:
A calorimeter measures the deposition of energy along the trajectory of particles created in or scattered by a collision. Since other, more precise or better suited methods for measuring electromagnetic particles such as electron and muons exist, calorimeters are mostly used for hadrons. And it is highly likely that it be digital, because without a trigger for choosing ~200 events per second to be saved and processed out of hundreds of thousands that actually ocur every second, you'd have yourself a nice, useless analog calorimeter.
So yeah, "Digital Hadron Calorimeter" is a bit of a buzzword-fest, but it gets the message across.
I'm not sure it was ever supposed to apply to photons in any case.
Probably not, since photons, being their own antiparticles, never had arrows attached to them in Feynman graphs to begin with.
div B = 0
equation were modified to read, say
div B = rho_m / mu_0
in analogy to Gauss' law. The defining qualities of Maxwell's model, such as the compliance with relativity, would remain intact.
For further reading on this, David J. Griffiths' 'Introduction to Electrodynamics' is many a professor's first recommendation to students.