National Institute of Standards and Technology (NIST)

Quantum may seem very intimidating, but there are resources to break down this complicated topic. You can explore quantum physics with The Quantum Atlas’s interactives, animations and explainers. Take a small step into the realm of the very small: https://lnkd.in/eaqw7xM5 Image credit: Eileen Stauffer/The Quantum Atlas

Good measurements and standards are critical for all areas of science and technology, so it’s no surprise that NIST’s work covers an ultrawide breadth of topics. A new place to sample our agency’s range of subject areas is our NIST Works for You section, which includes such topics as next-generation MRIs, fair fuel transactions and nuclear security. Another way to see the variety of NIST activity is through our blog post on our most popular reference materials, from Charpy steel bars to engineered antibodies. To learn more about how standards tie all this work together, check out our feature story on why we need standards.

Particles called neutrons usually live inside the cores of atoms, but they can also exist on their own. How long do these free-floating neutrons live? The NIST Center for Neutron Research is helping to answer that question. Free neutrons have a lifetime of about 15 minutes on average before they transform, or decay, into other particles such as protons. The process helps us understand a fundamental force of nature, known as the weak nuclear force, which causes radioactive particles to decay. A better measurement of the neutron lifetime would give physicists greater clarity about the way our universe works. NIST researchers send a beam of slow-moving neutrons through an electromagnetic trap, which catches protons that emerge from the neutrons’ decay. Counting the protons in the trap helps reveal how many neutrons decayed in a given time period. However, similar experiments at different labs have yielded answers that vary by nearly ten seconds. NIST scientists want to figure out where the difference is coming from. Could it be that some unwanted substance is sneaking into the trap somehow? The physicists considered the possibility that a few hydrogen molecules might be contaminating the trap. So, the team examined the experimental data again for any evidence that hydrogen might be present. After a close look, the team found a very low likelihood that hydrogen was the culprit. We still don’t know the reason why the discrepancy exists. But we know one reason it doesn’t, and that gets us closer to the answer.

After the 2010 Nashville floods, NIST researcher Christina Gore watched her community have to adapt. She didn’t know the term at the time, but recovering from and preparing for natural disasters is called community resilience. Today, Christina is a community resilience researcher helping others prepare for disasters. Learn more in our latest Taking Measure blog post: https://lnkd.in/exQDywqt

NIST researchers and their colleagues have demonstrated a method to distinguish century-old coins from fakes by imaging antique coins with beams of low-energy neutrons. Authenticating coins is critical because scientists rely on them to chronicle the economic, political, and scientific developments of nations. NIST researcher Daniel Hussey and his colleagues chose neutrons to examine two Korean coins—one minted in the 1800s, the other a replica—because these subatomic particles penetrate heavy metals, such as copper, iron, and lead, and interact strongly with hydrogen-bearing compounds that form as a byproduct of corrosion. The location and pattern of corrosion within the two coins, both composed of copper alloys, provided hallmarks for verifying their age. For instance, the neutron study revealed that in the authentic coin, corrosion had penetrated deep within the body, indicating that the degradation was a gradual process that occurred over many decades. In contrast, corrosion in the recently minted replica was mainly confined to the surface, consistent with rapid corrosion over a short time period. Neutron imaging methods can also assist conservation efforts by determining the amount and locations of corrosion in authentic coins, suggesting areas of the coins that need a protective coating, for example.

Freezing temperatures across the country have many of us saying, “This is as cold as it gets.” Physics disagrees. In 1848, Lord Kelvin calculated the coldest possible temperature – known as absolute zero. Today, the metric unit for temperature is named the kelvin. Chill out with this Taking Measure blog post to learn more about Lord Kelvin and his work: https://lnkd.in/ez6fJnHV

Portable generators emit deadly carbon monoxide (CO) that you can't see or smell. Never put a generator indoors (including a garage, basement or crawlspace), even if you keep doors and windows open. Using a generator outside, but too close to the home, can also be dangerous. Put generators at least 7.6 m (25 feet) from your home and point the exhaust away from any open windows, doors and vents to keep CO from getting in.

Every airplane has at least one airspeed sensor (also known as an anemometer), a necessary tool that helps pilots safely operate the aircraft. The lift that keeps an airplane aloft is created as wind rushes over its wings, so knowing that airspeed is crucial for maintaining lift. While GPS navigation systems can determine a plane’s ground speed, airspeed is the metric of success for lifting the plane into the sky and helping it descend to a safe landing. Specifically for landing, it is crucial to approach a runway with as little ground speed as possible for a smooth contact with the ground. But it is a balancing act between lowering ground speed and maintaining the lift for a controlled landing. Airspeed sensors keep pilots in control during the descent, so it’s essential that the sensors are regularly calibrated to ensure accuracy. Just about every airspeed sensor in the United States can trace its calibration back, either directly or indirectly via calibration laboratories, to a wind tunnel on NIST’s Gaithersburg, Maryland, campus.

Scientists measure everything from the concentration of molecules in a cell to the number of stars in space. They even measure narrow beams of laser light. At NIST, researchers measure the laser power of these beams using a device called the high amplification laser-pressure optic (HALO). The device can measure laser power up to 10 kilowatts, which is more powerful than 10 million laser pointers. It works by firing a laser at a mirror on the device, and researchers then measure the force of the laser’s reflection to determine its power. By measuring laser power, scientists can help improve the safety, quality control and performance of lasers over time. That’s important for fields where a lot of laser power is needed in a focused, localized area, such as 3D printing, manufacturing and testing new materials. The instrument is incredibly sensitive to changes in the lab ... and also outside of it. During the early stages of development, researchers noticed something curious. Every so often, a blip or spike occurred in the data produced by the device. After much speculation, they finally realized the blip was caused by something outside the lab. They hypothesized that the air pressure created by doors opening and closing in the hallway outside was causing these blips. How? The air currents generated from the doors traveled through the HVAC system and into the lab. The mirror on the instrument was so sensitive to air pressure disturbances that it picked up on them. The instrument and the surrounding lab space have been updated, and researchers now account for these environmental disturbances.

The Charpy impact test is one of the most common ways to measure the toughness of metals. It helps make sure the buildings you inhabit and the bridges you drive or walk over are safe. The Charpy standard reference material is one of our most popular standard reference materials (SRMs). SRMs are critical to supporting American industry, enforcing laws and conducting research. Learn more about this SRM and other popular reference materials in our latest Taking Measure blog post: https://lnkd.in/e6DKZRKz