Last week in Science magazine a large international team of physicists reported a slam-bang success for one of the most eery and majestic scientific instruments ever built. It is IceCube, an array of 5160 photodetectors and other exotic gear bolted into transparent spheres and lowered like basketball-sized beads on 86 strings more than a mile into the Antarctic ice cap, right at the South Pole.
I'll get to a news roundup in a moment. Its lesson will be that much of the covereage is likely to be incomprehensible to most readers. Exciting yes, digestible no, even if the Science paper was accompanied by more than half a dozen press releases to do some preliminary chewing for reporters. Better yet for inspiring a sort of faux comprehension, some of the 28 neutrinos in the report have Sesame Street nicknames including Bert and Ernie. But just to tell readers that this device saw neutrinos with far more zap and apparently from more distant places of ghastly violence than any neutrinos seen before and to get in some quotes leaves little room for background or physics of neutrinos to make the news sensible. The world thus got a river of gee-whiz. That is fine, of course. But it does not provide much to support a decent conversation among laymen about the so-what aspect other than to shake heads in unison at the crazy stuff that scientists are finding. It's a common problem with news from the cutting edges of scientific discovery. And a truth is, despite tight space and limited time several top science reporters tackled this task with pretty good result.
The instrument itself is such an elegant masterpiece that this merits the extensive, if not fully expansive, coverage that the news received.
A bit of background on the scale of this project: It took close to $300 million mainly from the Nat'l Science Foundation and seven years to melt and drill holes in the ice, lower the gizmos on cables and then let water in the holes refreeze around them, and get the whole thing wired and working. Shielded from cosmic rays, far from radioactive minerals, the devices are thus in a dark, cold, crystalline place where nothing much disturbs their subatomic solitude – except neutrinos. Zillions of them go through the Earth every second. Many are from nearish places – the Sun, and spat out by upper atmosphere molecules smacked by fast-moving protons and other nuclear cosmic ray particles, etc. Scads of low energy neutrinos are still adrift everywhere, leftovers of the Big Bang. Look up neutrinos, if you need a refresher, for they are weird indeed with next to no mass, no charge, a velocity near that of light, and an ability to carry energy. They interact so rarely with ordinary matter they tend to go through stuff unscathed and unfelt. They were imagined – sort of like fudge factors to balance energy inputs and outputs of certain nuclear decays – long before they were proven to exist. Heavy effort in the last few decades has gone into detecting neutrinos, with considerable success. Remember the exciting mistake in Europe a few years back, when an Italian team wondered why neutrinos from the CERN lab to their north seemed to have gotten to them faster than light? And a supernova seen in 1987 that spat so many neutrinos that detectors on Earth lit up? And the realization that the Sun's "missing" neutrinos are not missing, but disguise themselves into an unexpected 'flavor' en route? Neutrinos are not new but they remain odd.
Ice Cube is the most lavish neutrion detector yet built. It is geared to detect neutrinos carrying many orders of magnitude more energy than any discovered before. Such energies are presumably from exceedingly violent, hot, dense regions of space where broad stretches of intense magnetic and electric fields slam plasmatic wads of interstellar medium and star stuff into one another. The collision energies are assumed to be far beyond that possible on any Earthly accelerator. So they say. Super powerful cosmic rays already suggest that such natural cosmic accelerators exist. One cannot accelerate a neutrino – no electric charge to grab onto – but they are byproducts of particle collisions that render nucleons into quark puree. The most powerful cosmic rays – being electrically charged – don't go in nice straight lines as they transit galaxies. So no telling where they started by netting them here. Neutrinos do, pretty much. And if you can catch a bunch of these super energetic neutrinos, they should tell us the locations and some of the physics of the cosmic mosh pits that birthed them.
Whew. This news seems to vindicate the Ice Cube go-ahead and to open a path to a new genre of physics: neutrino astronomy. That part does get into all the news stories:
Speaking of which, here are some of the better ones + one for contrast from an aggregator:
- LA Times – Amina Khan: 28 neutrinos from outside the solar system open new era in astronomy ; Whoosh – first quote predicts a Nobel Prize for somebody (the paper has about 250 authors – one guesses by fast-counting the rows of names). Very nice pace to the story, which would need to be far longer to get into the rich history and context necessary. But Khan gives it a good go, using such easy-reading passages as "such standoffishness is exactly what makes neutrinos so hard to detect."
- NYTimes – Kenneth Chang: An Icy Observatory Detects Neutrions From Far, Far Away ; Says little about how the roughly straightline travel is what makes neutrinos so good for astronomy, but does get into a remaining mystery: expectation by some that even more-energetic ones should have been snared. Also has one neutrino, nicknamed Big Bird, that the team has discovered (see UC Berkeley release in Grist below) since the two-year run that provided the data for the Science paper.
- Milwaukee Journal-Sentinel – Mark Johnson: UW-led research into neutrinos unlocks clues to massive cosmic rays ; The PI is at Madison as is the collaboration's hq, and campus physicists were key to an earlier smaller Antarctic detector called Amanda, making this a local story for Johnson. This as do other stories says that one in a million of these very high energy neutrinos will be detected as it passes through IceCube's arrays. That seems like a lot compared to other super-elusive neutrinos. One wonders if high energy gives them high cross sections for collision?
- Christian Science Monitor – Ellizabeth Barber: Subatomic particles found in mile-deep ice are of interstellar origins ; The hed is misleading, but the story is unusual – among its first topics is the history of the "poltergeists from the Milky Way's fringes, with Fermi and Pauli's early speculations. Only after more than half way through does the naive readers learn that the subatomics particles of the hed were not found buried in the ice somehow, but were passing through at near light speed.
- NBCNews – Alan Boyle: Alien neutrinos reveal new frontier in astronomy at Antarctica's IceCube ; Boyle doesn't use the term Cherenkov radiation, but comes close by describing the "blue glow" of muons in the IceCube's grasp.
- Telegraph (UK) Richard Gray: Telescope buried in Antarctic ice detects elusive neutrinos ; Fairly routine, but does say something I'd missed in other stories: that an upgrade to IceCube might permit a mapping project to locate the places in the sky where these powerful neutrinos are born.
- Edmonton Journal – Alexandra Zabjek: University of Alberta scientists helop unlock secrets of the universe ; Hyperlocal news focus here, right down to the illus, a glamorous shot of a doctoral student at the local U. Story's a decent effort with no gross errors and a sense that something important happened.
- Popular Mechanics – Ashley Taylor: Found: Neutrinos From Beyond the Solar System ; Hed's off (those 1987a neutrinos were from a supernova far away), but story's ok including deft explanation how by working backwards physicists and astronomers now hope to pinpoint where these mega-energetic neutrinos come from.
- SpaceDaily – Staff Writers : IceCube pushes neutrinos to the forefront of astronomy ; Yikes, staff writers, you write just like the hard-working agents of the ICeCube collaboration who put out the press release (See Grist) from U. Wisconsin.
- Could go on but gotta get ready to go to visit the SoCal wing of the family for Thanksgiving.
Grist for the Mill: Nat'l Science Foundation Press Release ; German Electon-Synchrotron Lab (DESY) Press Release, U. Wisc. Press Release ; U. Alberta Press Release ; U. Maryland Press Release ; UC Berkeley Lawrence Berkeley Nat'l Lab Press Release ; Technical U. of Munich Press Release ; J. Gutenberg U. at Mainz Press Release;
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