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Annette Michelson, Influential Film Writer, Is Dead at 95

NY Times - Tue, 2018-09-18 12:44
She was a founder of the arts journal October and helped turn cinema studies into its own discipline.

Anita Hill: Senate should 'do better' than it did in 1991

CNN - Tue, 2018-09-18 12:43
Anita Hill on Tuesday called for the Senate to handle the allegation of sexual and physical assault against Supreme Court nominee Brett Kavanaugh better than it did her accusation of sexual harassment against now-Justice Clarence Thomas nearly 30 years ago.

Op-Docs: Among the Mangroves, a Girl Learns to Swim

NY Times - Tue, 2018-09-18 12:43
In a small Colombian village, a mother guides her daughter through a rite of passage.

See Victoria Beckham's Spice Girls dance

CNN - Tue, 2018-09-18 12:40
Victoria Beckham created buzz on the internet by posting video of her dancing to a Spice Girls song at an event in London.

Russia blames Israel after plane downed in Syria

CNN - Tue, 2018-09-18 12:39
Syria inadvertently shot down a Russian military plane after an Israeli attack on Syrian positions, killing 15 people on board, Moscow said.

Florence Engulfs Hog Farms And Chicken Houses, Thrashing North Carolina Agriculture

NPR All Things Considered - Tue, 2018-09-18 12:39

At least 1.7 million chickens have died from flooding in the state. The impact is now coming into focus — including overflowing pools of hog manure and waterlogged sweet potato fields.

(Image credit: Charles Mostoller/Bloomberg /Bloomberg via Getty Images)

Merkel’s Spy Chief Is Removed After Public Rift

NY Times - Tue, 2018-09-18 12:36
The standoff had raised questions about whether Germany’s security apparatus was too close to the far right to monitor extremist groups effectively.

Nobel laureates: We need justice in Myanmar

CNN - Tue, 2018-09-18 12:27
Today, the investigation led by the UN Independent International Fact-Finding Mission on Myanmar presented its findings to the Human Rights Council.

The Kavanaugh Allegations, and 5 (Misguided) Reasons People Doubt Victims

NY Times - Tue, 2018-09-18 12:26
Some common reasons for doubt, like a long delay before speaking out or a hazy recall of some details, are exactly what experts say they would expect to see after a sexual assault.

Analysis: What Emmy voters got right (and wrong)

CNN - Tue, 2018-09-18 12:24
The Emmy Awards featured their share of surprises -- putting prognosticators on their heels, and spreading the wealth among a number of networks. There was also a welcome mix of old and new, which is one of the unique challenges that TV faces, from recognizing that much-talked-about new series to paying homage to a long-running show in its final year.

Jerry Brown Made Climate Change His Issue. Now, He’s Not Sure How Much Politicians Can Do.

NY Times - Tue, 2018-09-18 12:21
The California governor, set to retire in January, made global warming a signature cause. His appraisal: “I don’t know if I’m an optimist. I’m a realist.”

Trump seeks to blunt future criticism by Democrats of Florence response

Washington Post - Tue, 2018-09-18 12:18
In a pair of tweets, the president predicted there would soon be “ranting” about perceived shortcomings.

Emmys Briefing: Emmys 2018: ‘Game of Thrones’ and ‘Marvelous Mrs. Maisel’ Win Big Awards

NY Times - Tue, 2018-09-18 12:17
It’s a tie: HBO and Netflix won 23 Emmys each. And it was a big night for Amazon’s “The Marvelous Mrs. Maisel,” which took five more awards.

Scientists catch Higgs boson particle’s most common decay

Futurity.org - Tue, 2018-09-18 12:15

CERN researchers have observed the Higgs boson particle transforming into bottom quarks as it decays.

Scientists predict this is the most common way for Higgs bosons to decay, yet it was a difficult signal to isolate because background processes closely mimic the subtle signal. This new discovery is a big step forward in the quest to understand how the Higgs enables fundamental particles to acquire mass.

After several years of refining their techniques and gradually incorporating more data, Large Hadron Collider collaborations ATLAS and CMS both finally saw evidence of the Higgs decaying to bottom quarks that exceeds the 5-sigma threshold of statistical significance typically required to claim a discovery. Both teams found their results were consistent with predictions based on the Standard Model.

Priority #1

“The Higgs boson is an integral component of our universe and theorized to give all fundamental particles their mass,” says Patty McBride, distinguished scientist at the US Department of Energy’s Fermi National Accelerator Laboratory. “But we haven’t yet confirmed exactly how this field interacts—or even if it interacts—with all the particles we know about, or if it interacts with dark matter particles, which remain to be detected.”

Only one out of a billion LHC collisions produces Higgs bosons and they live only a tiny fraction of a second before their energy is converted into a cascade of other particles. Because it’s impossible to see Higgs bosons directly, scientists use these secondary particle decay products to study the Higgs’ properties.

“We expected the Higgs would decay into bottom quarks most often, but it is crucial to see and measure it,” says Young-Kee Kim, a professor in physics and chair of the physics department at the University of Chicago, who worked on the bottom quark decay of the Higgs with the ATLAS experiment in the past. “We now have seen all of the primary decay modes of the Higgs predicted by the current theory of particle physics, the Standard Model. This marks a very important moment in particle physics!”

Since its discovery in 2012, scientists have been able to identify only about 30 percent of all the predicted Higgs boson decays. According to Viviana Cavaliere, a physicist at DOE’s Brookhaven National Laboratory who works on the ATLAS experiment, finding the Higgs boson decaying into bottom quarks has been priority number one for the last several years because of its large decay rate.

“Theory predicts that 60 percent of Higgs bosons decay into bottom quarks,” says Cavaliere, who is also using this process to search for new physics. “Finding and understanding this channel is critical because it opens up the possibility for us to examine the behavior of the Higgs, such as whether it could interact with new, undiscovered particles.”

Searching for more

“However, questions remain which cannot be answered by the Standard Model,” Kim says. “For example, is the Higgs responsible for giving mass to dark matter particles, the dominant form of matter in the universe?”

Scientists theorize that the Higgs field interacts with all massive particles in the Standard Model, the best theory scientists have to explain the behavior of subatomic particles. But many scientists suspect that the Higgs could also interact with massive particles outside the Standard Model, such as dark matter. By finding and mapping the Higgs bosons’ interactions with known particles, scientists can simultaneously probe for new phenomena.

“A fraction of Higgs bosons could be producing dark matter particles as part of their decay,” says Giacinto Piacquadio, a physicist at Stony Brook University who co-led the Higgs-to-bottom-quarks analysis group. “Because the decay of the Higgs boson to bottom quarks is so common, we can use it to put constraints on potentially invisible decays as well as use it to probe for new physics directly.”

No easy task

Even though this decay is the most popular path, spotting it in the experimental data was no walk in the park. Every proton-proton collision at the LHC produces a splattering of subatomic byproducts, one of the most common being bottom quarks. These bottom quarks then quickly decay into other kinds of particles, leaving behind vast showers of particles in the detectors. Tracing these particle showers back to two bottom quarks (and then figuring out which ones came from a Higgs boson) is extremely delicate and labyrinthine work.

“Being able to identify and isolate bottom quarks in the experimental data is a huge challenge and required precise detector calibration and sophisticated b-quark tagging,” says Piacquadio. “We were only able to do these analyses thanks to years of work that came before.”

To spot this process, the ATLAS and CMS collaborations each combined data from the first and second runs of the LHC and then applied complex analysis methods to the data.

“Finding just one event that looks like two bottom quarks originating from a Higgs boson is not enough,” says Chris Palmer, a scientist at Princeton University who worked on the CMS analysis. “We needed to analyze hundreds of thousands of events before we could illuminate this process, which is happening on top of a mountain of similar-looking background events.”

These deceptive background events made the analyses almost impossible to perform based on isolated bottom quarks alone, according to Palmer.

“Luckily, there are a few Higgs production mechanisms that produce identifiable particles as byproducts,” says Palmer. “We used these particles to tag potential Higgs events and separate them out from everything else. So we really got a two-for-one deal with this analysis because not only did we find the Higgs decaying to bottom quarks, but we also learned a lot about its production mechanisms.”

The next step is to increase the precision of these measurements so that scientists can study this decay mode with a much greater resolution and explore what secrets the Higgs boson might be hiding.

The Department of Energy Office of Science and the National Science Foundation funded the research.

Source: Stony Brook University, University of Chicago

The post Scientists catch Higgs boson particle’s most common decay appeared first on Futurity.

Anita Hill: How to Get the Kavanaugh Hearings Right

NY Times - Tue, 2018-09-18 12:14
The Senate Judiciary Committee has a chance to do better by the country than it did nearly three decades ago.

Trump jokes that he ‘better win the Hispanics next time.' He’d have to give up his base to do that.

Washington Post - Tue, 2018-09-18 12:07
Trump doesn't seem to understand why his olive branches to the Hispanic community are insufficient.
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