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Compelling evidence of neutrino process opens physics possibilities

Credit: Rex Tayloe/Indiana University The COHERENT particle physics experiment at the Department of Energy’s Oak Ridge National Laboratory has firmly established the existence of a new kind of neutrino interaction. Because neutrinos are electrically…

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Credit: Rex Tayloe/Indiana University

The COHERENT particle physics experiment at the Department of Energy’s Oak Ridge National Laboratory has firmly established the existence of a new kind of neutrino interaction. Because neutrinos are electrically neutral and interact only weakly with matter, the quest to observe this interaction drove advances in detector technology and has added new information to theories aiming to explain mysteries of the cosmos.

“The neutrino is thought to be at the heart of many open questions about the nature of the universe,” said Indiana University physics professor Rex Tayloe. He led the installation, operation and data analysis of a cryogenic liquid argon detector for neutrinos at the Spallation Neutron Source, or SNS, a DOE Office of Science User Facility at ORNL.

The study, published in Physical Review Letters, observed that low-energy neutrinos interact with an argon nucleus through the weak nuclear force in a process called coherent elastic neutrino-nucleus scattering, or CEvNS, which is pronounced “sevens.” Like a ping-pong ball bombarding a softball, a neutrino that hits a nucleus transfers only a small amount of energy to the much larger nucleus, which recoils almost imperceptibly in response to the tiny assault.

Laying the groundwork for the discovery made with the argon nucleus was a 2017 study published in Science in which COHERENT collaborators used the world’s smallest neutrino detector to provide the first evidence of the CEvNS process as neutrinos interacted with larger and heavier cesium and iodide nuclei. Their recoils were even tinier, like bowling balls reacting to ping-pong balls.

“The Standard Model of Particle Physics predicts coherent elastic scattering of neutrinos off nuclei,” said Duke University physicist Kate Scholberg, spokesperson and organizer of science and technology goals for COHERENT. The collaboration has 80 participants from 19 institutions and four countries. “Seeing the neutrino interaction with argon, the lightest nucleus for which it has been measured, confirms the earlier observation from heavier nuclei. Measuring the process precisely establishes constraints on alternative theoretical models.”

Yuri Efremenko, a physicist at the University of Tennessee, Knoxville, and ORNL who led development of more sensitive photodetectors, said, “Argon provides a ‘door’ of sorts. The CEvNS process is like a building that we know should exist. The first measurement on sodium and iodide was one door that let us in to explore the building. We’ve now opened this other argon door.” The argon data is consistent with the Standard Model within error bars. However, increased precision enabled by bigger detectors may let scientists see something new. “Seeing something unexpected would be like opening the door and seeing fantastic treasures,” Efremenko added.

“We’re looking for ways to break the Standard Model. We love the Standard Model; it’s been really successful. But there are things it just doesn’t explain,” said physicist Jason Newby, ORNL’s lead for COHERENT. “We suspect that in these small places where the model might break down, answers to big questions about the nature of the universe, antimatter and dark matter, for instance, could lie in wait.”

The COHERENT team uses the world’s brightest pulsed neutron source at SNS to help find the answers. The neutrons SNS produces for research create neutrinos as a byproduct. A service corridor beneath the SNS mercury target has been converted into a dedicated neutrino laboratory, dubbed Neutrino Alley, under the leadership of Newby and Efremenko. A 53-pound, or 24-kilogram, detector called CENNS-10 sits 90 feet, or 27.5 meters, from a low-energy neutrino source that optimizes opportunities to spot interactions that are coherent. This means approaching neutrinos see the weak force of the nucleus as a whole, leading to a bigger effect as compared to non-coherent interactions.

Bigger detectors are better at making high-precision measurements, and the CENNS-10 detector technology is easy to scale up by merely adding more liquid argon.

The CENNS-10 detector was originally built at Fermilab by COHERENT collaborator Jonghee Yoo. He and Tayloe brought it to IU and reworked it there before it was installed at SNS in 2016. Newby and Efremenko had prepared the SNS site with shielding of layered lead, copper and water to eliminate neutron backgrounds.

After initial measurements indicated the experiment would not be dominated by background, wavelength-shifting coatings were applied to the photodetectors and inner reflectors that significantly improved light collection. The detector was calibrated by injecting krypton-83m into the liquid argon to allow calculation of the number of photons present.

The published results used 18 months of data collected from CENNS-10. Analysis of the data revealed 159 CEvNS events, consistent with the Standard Model prediction.

COHERENT’s data will help researchers worldwide interpret their neutrino measurements and test their theories of possible new physics. The calculable fingerprint of neutrino-nucleus interactions predicted by the Standard Model and seen by COHERENT has practical applications, too. “This is a way to measure the distribution of neutrons inside nuclei and the density of neutron stars,” Efremenko said. “It’s a contribution to nuclear physics and astrophysics because the processes are very similar.”

Different types of detectors are necessary for comprehensive neutrino studies. To further the goal of observing CEvNS on a variety of nuclei, a 16-kilogram detector based on germanium nuclei, which are bigger than argon but smaller than cesium and iodide, will be installed in Neutrino Alley next year. An array of sodium iodide detectors has been installed to augment the cesium iodide detector in operation there since 2017.

Meanwhile, data collection continues 24/7 despite COVID-19 because COHERENT collaborators monitor their liquid argon detector remotely. They aspire to enlarge it to ton-scale to see 25 times as many events annually and enable observation of detailed energy spectra that could reveal signatures of the new physics, including the existence of sterile neutrinos that have no weak interaction and, therefore, would not demonstrate a coherent interaction.

Eventually, they would like to add an even bigger 10-ton, liquid-argon detector at SNS’s Second Target Station. “We’re pushing on the technology so that, in the future, we will be able to answer questions that require greater precision,” Newby said.

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The title of the Physical Review Letters paper is “First Detection of Coherent Elastic Neutrino-Nucleus Scattering on Argon.”

The DOE Office of Science Graduate Student Research (SCGSR) Program, Alfred P. Sloan Foundation, Consortium for Non-proliferation Enabling Capabilities, Korea’s Institute for Basic Science, U.S. National Science Foundation, and Russian Foundation for Basic Research supported the research. ORNL’s Laboratory Directed Research and Development Program funded local siting studies and installation to establish the experiment at the SNS. DOE’s Fermilab continues to loan the CENNS-10 detector. This research used resources of the Oak Ridge Leadership Computing Facility, a DOE Office of Science User Facility at ORNL.

UT-Battelle manages ORNL for the Department of Energy’s Office of Science, the single largest supporter of basic research in the physical sciences in the United States. The Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit energy.gov/science.

PHOTO SLIDESHOW

IMAGE_8455_corrected

SCGSR Awardee Jacob Zettlemoyer, Indiana University Bloomington, led data analysis and worked with ORNL’s Mike Febbraro on coatings, shown under blue light, to shift argon light to visible wavelengths to boost detection. Credit: Rex Tayloe/Indiana University

SLIDESHOW 3_SNS May2015_Arieal_5W8A6989.jpg

The Spallation Neutron Source also produces neutrinos in large quantities. Credit: Jason Richards/ORNL, U.S. Dept. of Energy

IMG_8563

Indiana University physics undergraduate Maria del Valle Coello views the CENNS-10 detector installed in SNS’s Neutrino Alley. Credit: Rex Tayloe/Indiana University

Media Contact
Dawn Levy
levyd@ornl.gov

Original Source

https://www.ornl.gov/news/compelling-evidence-neutrino-process-opens-physics-possibilities

Related Journal Article

http://dx.doi.org/10.1103/PhysRevLett.126.012002

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Government

Supreme Court Rules Public Officials May Block Their Constituents On Social Media

Supreme Court Rules Public Officials May Block Their Constituents On Social Media

Authored by Matthew Vadum via The Epoch Times (emphasis…

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Supreme Court Rules Public Officials May Block Their Constituents On Social Media

Authored by Matthew Vadum via The Epoch Times (emphasis ours),

Public officials may block people on social media in certain situations, the Supreme Court ruled unanimously on March 15.

People leave the U.S. Supreme Court in Washington on Feb. 21, 2024. (Kevin Dietsch/Getty Images)

At the same time, the court held that public officials who post about topics pertaining to their work on their personal social media accounts are acting on behalf of the government. But such officials can be found liable for violating the First Amendment only when they have been properly authorized by the government to communicate on its behalf.

The case is important because nowadays public officials routinely reach out to voters through social media on the same pages where they discuss personal matters unrelated to government business.

When a government official posts about job-related topics on social media, it can be difficult to tell whether the speech is official or private,” Justice Amy Coney Barrett wrote for the nation’s highest court.

The case is separate from but brings to mind a lawsuit that several individuals previously filed against former President Donald Trump after he blocked them from accessing his social media account on Twitter, which was later renamed X. The Supreme Court dismissed that case, Biden v. Knight First Amendment Institute, in April 2021 as moot because President Trump had already left office.

At the time of the ruling, the then-Twitter had banned President Trump. When Elon Musk took over the company he reversed that policy.

The new decision in Lindke v. Freed was written by Justice Amy Coney Barrett.

Respondent James Freed, the city manager of Port Huron, Michigan, used a public Facebook account to communicate with his constituents. Petitioner Kevin Lindke, a resident of Port Huron, criticized the municipality’s response to the COVID-19 pandemic, including accusations of hypocrisy by local officials.

Mr. Freed blocked Mr. Lindke and others and removed their comments, according to Mr. Lindke’s petition.

The U.S. Court of Appeals for the 6th Circuit ruled for Mr. Freed, finding that he was acting only in a personal capacity and that his activities did not constitute governmental action.

Mr. Freed’s attorney, Victoria Ferres, said during oral arguments before the Supreme Court on Oct. 31, 2023, that her client didn’t give up his rights when using social media.

This country’s 21 million government employees should have the right to talk publicly about their jobs on personal social media accounts like their private-sector counterparts.”

The position advocated by the other side would unfairly punish government officials, and “will result in uncertainty and self-censorship for this country’s government employees despite this Court repeatedly finding that government employees do not lose their rights merely by virtue of public employment,” she said.

In Lindke v. Freed, the Supreme Court found that a public official who prevents a person from comments on the official’s social media pages engages in governmental action under Section 1983 only if the official had “actual authority” to speak on the government’s behalf on a specific matter and if the official claimed to exercise that authority when speaking in the relevant social media posts.

Section 1983 refers to Title 42, U.S. Code, Section 1983, which allows people to sue government actors for deprivation of civil rights.

Justice Barrett wrote that according to the so-called state action doctrine, the test for “actual authority” must be “rooted in written law or longstanding custom to speak for the State.”

“That authority must extend to speech of the sort that caused the alleged rights deprivation. If the plaintiff cannot make this threshold showing of authority, he cannot establish state action.”

“For social-media activity to constitute state action, an official must not only have state authority—he must also purport to use it,” the justice continued.

State officials have a choice about the capacity in which they choose to speak.

Citing previous precedent, Justice Barrett wrote that generally a public employee claiming to speak on behalf of the government acts with state authority when he speaks “in his official capacity or” when he uses his speech to carry out “his responsibilities pursuant to state law.”

“If the public employee does not use his speech in furtherance of his official responsibilities, he is speaking in his own voice.”

The Supreme Court remanded the case to the 6th Circuit with instructions to vacate its judgment and ordered it to conduct “further proceedings consistent with this opinion.”

Also on March 15, the Supreme Court ruled on O’Connor-Ratcliff v. Garnier, a related case. The court’s sparse, unanimous opinion was unsigned.

Petitioners Michelle O’Connor-Ratcliff and T.J. Zane were two elected members of the Poway Unified School District Board of Trustees in California who used their personal Facebook and Twitter accounts to communicate with the public.

Respondents Christopher Garnier and Kimberly Garnier, parents of local students, “spammed Petitioners’ posts and tweets with repetitive comments and replies” so the school board members blocked the respondents from the accounts, according to the petition filed by Ms. O’Connor-Ratcliff and Mr. Zane.

But the Garniers said they were acting in good faith.

“The Garniers left comments exposing financial mismanagement by the former superintendent as well as incidents of racism,” the couple said in a brief.

The U.S. Court of Appeals for the 9th Circuit found in favor of the Garniers, holding that elected officials using social media accounts were participating in a public forum.

The Supreme Court ruled in a three-page opinion that because the 9th Circuit deviated from the standard the high court articulated in Lindke v. Freed, the 9th Circuit’s decision must be vacated.

The case was remanded to the 9th Circuit “for further proceedings consistent with our opinion” in the Lindke case, the Supreme Court stated.

Tyler Durden Sun, 03/17/2024 - 22:10

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International

Home buyers must now navigate higher mortgage rates and prices

Rates under 4% came and went during the Covid pandemic, but home prices soared. Here’s what buyers and sellers face as the housing season ramps up.

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Springtime is spreading across the country. You can see it as daffodil, camellia, tulip and other blossoms start to emerge. 

You can also see it in the increasing number of for sale signs popping up in front of homes, along with the painting, gardening and general sprucing up as buyers get ready to sell. 

Which leads to two questions: 

  • How is the real estate market this spring? 
  • Where are mortgage rates? 

What buyers and sellers face

The housing market is bedeviled with supply shortages, high prices and slow sales.

Mortgage rates are still high and may limit what a buyer can offer and a seller can expect.  

Related: Analyst warns that a TikTok ban could lead to major trouble for Apple, Big Tech

And there's a factor not expected that may affect the sales process. Fixed commission rates on home sales are going away in July.

Reports this week and in a week will make the situation clearer for buyers and sellers. 

The reports are:

  • Housing starts from the U.S. Commerce Department due Tuesday. The consensus estimate is for a seasonally adjusted rate of about 1.4 million homes. These would include apartments, both rentals and condominiums. 
  • Existing home sales, due Thursday from the National Association of Realtors. The consensus estimate is for a seasonally adjusted sales rate of about 4 million homes. In 2023, some 4.1 million homes were sold, the worst sales rate since 1995. 
  • New-home sales and prices, due Monday from the Commerce Department. Analysts are expecting a sales rate of 661,000 homes (including condos), up 1.5% from a year ago.

Here is what buyers and sellers need to know about the situation. 

Mortgage rates will stay above 5% 

That's what most analysts believe. Right now, the rate on a 30-year mortgage is between 6.7% and 7%. 

Rates peaked at 8% in October after the Federal Reserve signaled it was done raising interest rates.

The Freddie Mac Primary Mortgage Market Survey of March 14 was at 6.74%. 

Freddie Mac buys mortgages from lenders and sells securities to investors. The effect is to replenish lenders' cash levels to make more loans. 

A hotter-than-expected Producer Price Index released that day has pushed quotes to 7% or higher, according to data from Mortgage News Daily, which tracks mortgage markets.

Home buyers must navigate higher mortgage rates and prices this spring.

TheStreet

On a median-priced home (price: $380,000) and a 20% down payment, that means a principal and interest rate payment of $2,022. The payment  does not include taxes and insurance.

Last fall when the 30-year rate hit 8%, the payment would have been $2,230. 

In 2021, the average rate was 2.96%, which translated into a payment of $1,275. 

Short of a depression, that's a rate that won't happen in most of our lifetimes. 

Most economists believe current rates will fall to around 6.3% by the end of the year, maybe lower, depending on how many times the Federal Reserve cuts rates this year. 

If 6%, the payment on our median-priced home is $1,823.

But under 5%, absent a nasty recession, fuhgettaboutit.

Supply will be tight, keeping prices up

Two factors are affecting the supply of homes for sale in just about every market.

First: Homeowners who had been able to land a mortgage at 2.96% are very reluctant to sell because they would then have to find a home they could afford with, probably, a higher-cost mortgage.

More economic news:

Second, the combination of high prices and high mortgage rates are freezing out thousands of potential buyers, especially those looking for homes in lower price ranges.

Indeed, The Wall Street Journal noted that online brokerage Redfin said only about 20% of homes for sale in February were affordable for the typical household.

And here mortgage rates can play one last nasty trick. If rates fall, that means a buyer can afford to pay more. Sellers and their real-estate agents know this too, and may ask for a higher price. 

Covid's last laugh: An inflation surge

Mortgage rates jumped to 8% or higher because since 2022 the Federal Reserve has been fighting to knock inflation down to 2% a year. Raising interest rates was the ammunition to battle rising prices.

In June 2022, the consumer price index was 9.1% higher than a year earlier. 

The causes of the worst inflation since the 1970s were: 

  • Covid-19 pandemic, which caused the global economy to shut down in 2020. When Covid ebbed and people got back to living their lives, getting global supply chains back to normal operation proved difficult. 
  • Oil prices jumped to record levels because of the recovery from the pandemic recovery and Russia's invasion of Ukraine.

What the changes in commissions means

The long-standing practice of paying real-estate agents will be retired this summer, after the National Association of Realtors settled a long and bitter legal fight.

No longer will the seller necessarily pay 6% of the sale price to split between buyer and seller agents.

Both sellers and buyers will have to negotiate separately the services agents have charged for 100 years or more. These include pre-screening properties, writing sales contracts, and the like. The change will continue a trend of adding costs and complications to the process of buying or selling a home.

Already, interest rates are a complication. In addition, homeowners insurance has become very pricey, especially in communities vulnerable to hurricanes, tornadoes, and forest fires. Florida homeowners have seen premiums jump more than 102% in the last three years. A policy now costs three times more than the national average.

Related: Veteran fund manager picks favorite stocks for 2024

 

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Default: San Francisco Four Seasons Hotel Investors $3 Million Late On Loan As Foreclosure Looms

Default: San Francisco Four Seasons Hotel Investors $3 Million Late On Loan As Foreclosure Looms

Westbrook Partners, which acquired the San…

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Default: San Francisco Four Seasons Hotel Investors $3 Million Late On Loan As Foreclosure Looms

Westbrook Partners, which acquired the San Francisco Four Seasons luxury hotel building, has been served a notice of default, as the developer has failed to make its monthly loan payment since December, and is currently behind by more than $3 million, the San Francisco Business Times reports.

Westbrook, which acquired the property at 345 California Center in 2019, has 90 days to bring their account current with its lender or face foreclosure.

Related

As SF Gate notes, downtown San Francisco hotel investors have had a terrible few years - with interest rates higher than their pre-pandemic levels, and local tourism continuing to suffer thanks to the city's legendary mismanagement that has resulted in overlapping drug, crime, and homelessness crises (which SF Gate characterizes as "a negative media narrative).

Last summer, the owner of San Francisco’s Hilton Union Square and Parc 55 hotels abandoned its loan in the first major default. Industry insiders speculate that loan defaults like this may become more common given the difficult period for investors.

At a visitor impact summit in August, a senior director of hospitality analytics for the CoStar Group reported that there are 22 active commercial mortgage-backed securities loans for hotels in San Francisco maturing in the next two years. Of these hotel loans, 17 are on CoStar’s “watchlist,” as they are at a higher risk of default, the analyst said. -SF Gate

The 155-room Four Seasons San Francisco at Embarcadero currenly occupies the top 11 floors of the iconic skyscrper. After slow renovations, the hotel officially reopened in the summer of 2021.

"Regarding the landscape of the hotel community in San Francisco, the short term is a challenging situation due to high interest rates, fewer guests compared to pre-pandemic and the relatively high costs attached with doing business here," Alex Bastian, President and CEO of the Hotel Council of San Francisco, told SFGATE.

Heightened Risks

In January, the owner of the Hilton Financial District at 750 Kearny St. - Portsmouth Square's affiliate Justice Operating Company - defaulted on the property, which had a $97 million loan on the 544-room hotel taken out in 2013. The company says it proposed a loan modification agreement which was under review by the servicer, LNR Partners.

Meanwhile last year Park Hotels & Resorts gave up ownership of two properties, Parc 55 and Hilton Union Square - which were transferred to a receiver that assumed management.

In the third quarter of 2023, the most recent data available, the Hilton Financial District reported $11.1 million in revenue, down from $12.3 million from the third quarter of 2022. The hotel had a net operating loss of $1.56 million in the most recent third quarter.

Occupancy fell to 88% with an average daily rate of $218 in the third quarter compared with 94% and $230 in the same period of 2022. -SF Chronicle

According to the Chronicle, San Francisco's 2024 convention calendar is lighter than it was last year - in part due to key events leaving the city for cheaper, less crime-ridden places like Las Vegas

Tyler Durden Sun, 03/17/2024 - 18:05

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