Dark Matter Particles Detected?

Well, some physicists are excited about 2 events that could have been the detection of WIMPS in super-cooled crystals of germanium and silicon, in an experiment deep underground. But there is a 25% chance that it was just background radiation.

It is reported in Nature in the news section:
http://www.nature.com/news/2009/091223/full/462967a.html

As a U of M person, you can read Nature for free through your library account. The librarian, Bill, can set you up with a proxy on your browser so the article is a click away.

What Theorists are up to

http://arxiv.org/abs/0912.0520

Ordinary stars are powered by the fusion of light nuclei into heavier
ones -- such as hydrogen into helium in the center of our Sun.
Electroweak stars, they theorize, would be powered by the total
conversion of quarks -- the particles that make up the proton and
neutron building blocks of those nuclei -- into much lighter particles
called leptons. These leptons include electrons, but especially
elusive -- and nearly massless -- neutrinos.

XMM-Newton Celebration

Tooting its own horn:

XMM-Newton, the most powerful X-ray observatory ever built and
launched into space, marks its 10th anniversary on December 10th.
XMM-Newton’s observations have revolutionized the way we view the
hottest and most extreme regions of the Universe.

There is a list of accomplishments in the news release - which is now on the XXM news site itself...

A supernova that's the first of its kind

An extraordinarily bright, long-lasting supernova named SN 2007bi, snagged in a search by a robotic telescope, turns out to be the first example of the kind of stars that first populated the universe. The bright supernova occurred in a nearby dwarf galaxy, a kind of galaxy that's common but has been studied little until now. The unusual supernova could be the first of many such events soon to be discovered.

The supernova's spectrum was unusual, and the analysis indicated that the supernova's precursor star only could have been a giant weighing at least 200 times the mass of our Sun and initially containing few elements besides hydrogen and helium — a star like the very first stars in the early universe.

"Because the core alone was some 100 solar masses, the long-hypothesized phenomenon called pair instability must have occurred," said astrophysicist Peter Nugent, a member of the SNfactory. "In the extreme heat of the star's interior, energetic gamma rays created pairs of electrons and positrons, which bled off the pressure that sustained the core against collapse."

Read the full news here.

NASA's Fermi Telescope peers deep into a microquasar

NASA's Fermi Gamma-ray Space Telescope has made the first unambiguous detection of high-energy gamma-rays from an enigmatic binary system known as Cygnus X-3. The system pairs a hot, massive star with a compact object — either a neutron star or a black hole — that blasts twin radio-emitting jets of matter into space at more than half the speed of light.

At the center of Cygnus X-3 lies a massive Wolf-Rayet star. With a surface temperature of 180,000° Fahrenheit (100,000° Celsius), or about 17 times hotter than the Sun, the star is so hot that its mass bleeds into space in the form of a powerful outflow called a stellar wind. "In just 100,000 years, this fast, dense wind removes as much mass from the Wolf-Rayet star as our Sun contains," said Robin Corbet at the University of Maryland, Baltimore County.

Every 4.8 hours, a compact companion embedded in a disk of hot gas wheels around the star. "This object is most likely a black hole, but we can't yet rule out a neutron star," Corbet said.

Fermi's LAT detects changes in Cygnus X-3's gamma-ray output related to the companion's 4.8-hour orbital motion. The brightest gamma-ray emission occurs when the disk is on the far side of its orbit. "This suggests that the gamma rays arise from interactions between rapidly moving electrons above and below the disk and the star's ultraviolet light," Corbel said.

When ultraviolet photons strike particles moving at an appreciable fraction of the speed of light, the photons gain energy and become gamma rays. "The process works best when an energetic electron already heading toward Earth suffers a head-on collision with an ultraviolet photon," said Guillaume Dubus at the Laboratory for Astrophysics in Grenoble, France. "And this occurs most often when the disk is on the far side of its orbit."

Through processes not fully understood, some of the gas falling toward Cygnus X-3's compact object instead rushes outward in a pair of narrow, oppositely directed jets. Radio observations clock gas motion within these jets at more than half the speed of light.

Large Hadron Collider sets new world record

News release from Astronomy mag.

CERN's Large Hadron Collider (LHC) is now the world's highest energy particle accelerator, having accelerated its twin beams of protons to an energy of 1.18 TeV in the early hours of the morning. This exceeds the previous world record of 0.98 TeV that had been held by the U.S. Fermi National Accelerator Laboratory's Tevatron collider since 2001. It marks another important milestone on the road to first physics at the LHC in 2010.

First beams were injected into the LHC November 20. Over the following days, the machine's operators circulated beams around the ring alternately in one direction and then the other at the injection energy of 450 GeV, gradually increasing the beam lifetime to around 10 hours. On November 23, two beams circulated together for the first time, and the four big LHC detectors recorded their first collision data.

Last night's achievement brings further confirmation that the LHC is progressing smoothly towards the objective of first physics early in 2010. The world record energy was first broken November 29 when beam 1 was accelerated from 450 GeV, reaching 1050 GeV (1.05 TeV). Three hours later, November 30, both LHC beams were successfully accelerated to 1.18 TeV. First physics at the LHC is scheduled for the first quarter of 2010 at a collision energy of 7 TeV (3.5 TeV per beam).