They’re not quite to the promised land yet (even remembering that the beam energies are a lot lower than we eventually want them to be). A little while ago we had beam traveling through the accelerator, which is obviously a big step. These splash events happen when the beam collides into something “upstream,” creating a splash of particles that are then detected by the experiment. The big step will be when beams moving in opposite directions actually collide with each other inside the detector. I predict you’ll hear soon when that happens.

You can follow CMS at its Facebook fan page. 528 fans, I’m sure we can boost that number.

I already have a bet with Brian Schmidt that we will fine at least 3-sigma evidence for the Higgs within five years (either at Fermilab or the LHC). Feeling pretty optimistic right now.

The rehabilitation of the beleaguered Large Hadron Collider was on hold tonight after the failure of one of its powerful cooling units caused by an errant chunk of baguette.

You have to love YouTube, although this is only an excerpt from a somewhat longer speech. Most of the text is here.

A) Yes.

B) No.

C) Cannot be determined.

This is from this month’s Scientific American — article unfortunately costs money. It’s about “dysrationalia,” which is what happens when people with nominally high IQ’s end up thinking irrationally. A phenomenon I’m sure we’ve all encountered, especially in certain corners of the blogosphere.

And the answer is the first option. But over 80 percent of people choose the third option. Here’s the solution: the puzzle doesn’t say whether Anne is married or not, but she either is or she isn’t. If Anne is married, she’s looking at George, so the answer is “yes”; if she’s unmarried, Jack is looking at her, so the answer is still “yes.” The underlying reason why smart people get the wrong answer is (according to the article) that they simply don’t take the time to go carefully through all of the possibilities, instead taking the easiest inference. The patience required to go through all the possibilities doesn’t correlate very well with intelligence.

• STAR WARS Episodes IV-VI are to be referred to as “The Original Trilogy.” Episodes I-III are not to be referred to at all.
• Always capitalize Satan. You don’t want to get dead goats from those people.
• The correct spelling is “Rocktober,” not “Roctober,” which is the month of giant birds.
• Replace “situation deteriorated/worsened” with “shit [just] got real.” Ex: On day three of the hostage crisis, shit got real.

Amusing enough, but I have to admit that I originally read “Fake AP Stylebook” as “Fake APS Stylebook,” as if it were the (fake) American Physical Society rather than the (fake) Associated Press that was handing out advice. After all, the real APS is quite a bit quirkier than the AP; they insist that no article title begin with “The,” and for a while there they were insisting that “Lagrangian” be spelled “Lagrangean.” (Everyone has their quirks; Nature has banned the words “paradigm” and “scenario” from its pages entirely.)

So I’m sure we can do better. Any good suggestions for improved physics style? I promise to tweet anything sufficiently amusing.

1. Topic X is important and interesting.

2. But.

3. This is how we will address “But.”

The rest of the proposal reiterates those three points with enough detail to make it believable.

In a short proposal, the structure fills a paragraph. In a long proposal, it’s three paragraphs, and shouldn’t go past the first page.

The abstract is a 1 paragraph version of the same structure, with the addition of a closing rah rah rah sentence.

If you can’t bludgeon your introduction into this form, you might want to step back and regroup.

As promised, we’re also doling out some loot. For those having contributed over $100, we will arrange for a copy of Sean’s new book (you do know he has a book coming out, right?) to get to you, once it’s available (expected in early January). For contributions of $500 or more (of which there were at least five), a copy of Sean’s lectures on the dark universe will be forthcoming. To claim your thank you gift, please contact me (if you haven’t already) with your name and address, and the amount contributed.

Most importantly, thank you to everyone for making this an incredible success. I encourage you to read over the many thank you notes at our giving page, and hear about the direct impact you’ve all made on the lives of these children. And, of course, although the Media Challenge is officially over, there’s nothing to stop you from continuing to donate. There are still plenty of budding Einsteins, being held back by a lack of basic necessities that you could directly provide.

The Fermi Haze: A Gamma-Ray Counterpart to the Microwave Haze
Authors: Gregory Dobler, Douglas P. Finkbeiner, Ilias Cholis, Tracy R. Slatyer, Neal Weiner

Abstract: The Fermi Gamma-Ray Space Telescope reveals a diffuse inverse Compton signal in the inner Galaxy with the same spatial morphology as the microwave haze observed by WMAP, confirming the synchrotron origin of the microwaves. Using spatial templates, we regress out pi0 gammas, as well as ICS and bremsstrahlung components associated with known soft-synchrotron counterparts. We find a significant gamma-ray excess towards the Galactic center with a spectrum that is significantly harder than other sky components and is most consistent with ICS from a hard population of electrons. The morphology and spectrum are consistent with it being the ICS counterpart to the electrons which generate the microwave haze seen at WMAP frequencies. In addition to confirming that the microwave haze is indeed synchrotron, the distinct spatial morphology and very hard spectrum of the ICS are evidence that the electrons responsible for the microwave and gamma-ray haze originate from a harder source than supernova shocks. We describe the full sky Fermi maps used in this analysis and make them available for download.

In English: if the dark matter is a weakly-interacting massive particle (WIMP), individual WIMPs should occsasionally annihilate with other WIMPs, giving off a bunch of particles, including electron/positron pairs as well as high-energy photons (gamma rays). Indeed, searching for such gamma rays was one of the primary motivations behind the Fermi mission (formerly GLAST). And it makes sense to look where the dark matter is most dense, in the center of the galaxy. But it’s a very hard problem, for a simple reason — there’s lots of radiation coming from the center of the galaxy, most of which has nothing to do with dark matter. Subtracting off these “backgrounds” (which would be very interesting in their own right to galactic astronomers) is the name of the game in this business.

But Doug Finkbeiner at Harvard has for a while now been suggesting that there was already evidence for something interesting going on near the galactic center — not in the form of high-energy photons, but in the form of low-energy photons. The so-called WMAP haze is alleged to be radiation emitted when high-energy electrons are being accelerated by magnetic fields, leading to low-energy photons (synchrotron radiation). And Finkbeiner and collaborators claim that a careful analysis of data from WMAP (whose primary mission was to observe the cosmic microwave background) reveals exactly the kind of radiation you would expect from annihilations near the galactic center.

If that model is right, it gives us some guidance about what to look for in the gamma rays themselves, which Fermi is now observing. And according to this new paper, this is what we see.

That’s one of many images, and has been extensively processed; see paper for details. The new paper claims that there is an excess of gamma rays, and that it has just the right properties to be arising from the same population of electrons that gave rise to the WMAP haze. These much higher-energy photons arise from inverse Compton scattering — electrons bumping into photons and pushing them to higher energies — rather than synchrotron emission. So we’re not talking about gammas that are produced by dark-matter annihilations, but ones that might arise from electrons and positrons that are produced by such annihilations. The authors pointedly do not claim that what we see must arise from dark matter, or even delve very deeply into that possibility.

There have been speculations that the microwave haze could indicate new physics, such as the decay or annihilation of dark matter, or new astrophysics. We do not speculate in this paper on the origin of the haze electrons, other than to make the general observation that the roughly spherical morphology of the haze makes it difficult to explain with any population of disk objects, such as pulsars. The search for new physics – or an improved understanding of conventional astrophysics – will be the topic of future work.

That’s as it should be; whether or not the gamma-ray haze is real is a separate question from whether dark matter is the culprit. But on a blog we can speculate just a bit. Therefore I’m going to go out on a limb and say: maybe it is! Or maybe not. But a wide variety of promising experimental techniques are attacking the problem of detecting the dark matter, and we’ll be hearing a lot more in the days to come.

Now, via Dan Vergano’s Twitter feed, I see a story in Nature News to the effect that things have become murky once again. The proposals got too expensive, so NASA turned to the European Space Agency for help, but ended up giving away things the DOE thought were in their domain, so they threatened to take their toys and go home, giving up on the idea of a satellite altogether.

The story is complicated by disagreement over how important it is to measure the dark energy equation-of-state parameter, the number characterizing how quickly the energy density changes (if at all). It’s frequently said that “we know nothing” about dark energy, but that’s not true; we know that it’s smoothly distributed and nearly-constant in density through time. We even have a very natural candidate for what it is: the vacuum energy. There is of course the problem that the vacuum energy is much smaller than it should be, but that problem is there whether it’s strictly zero or just really small. Other models still have that problem, and tend to add other fine-tunings on top. It would be great, and we would certainly learn a lot, if the dark energy were not simply vacuum energy; but right now we have no compelling reason to think it’s not, so it’s a bit of a long shot.

The LHC machine commissioning will pick up where it left off more than a year ago, and the plan is, if all goes well, to collide beams of protons in the experiments at a center of mass energy of 7 TeV (3.5 TeV per beam) before the end of the year. The luminosity will not be large at first, but should increase steadily with time until next fall, when the long shutdown to retrofit the remaining magnets with new quench detection and helium pressure relief systems begins. By that point the experiments hope to have accumulated upwards of 200 pb^-1 of integrated luminosity. This initial data sample is sorely needed to shake down the detectors and start tuning up the event reconstruction and analysis. And who knows, maybe we’ll see something totally unexpected. (Please, no black hole comments!)

The next main milestone will be beam circulating around the whole ring and captured by the RF system. That should happen by mid-November. Fingers crossed!