Fermilab Today

Protons and neutrons are very similar particles in most respects. They're made of the same quarks, which are even smaller particles, and they have almost exactly the same mass.

Yet neutrons appear to be different from protons in an important way: They aren't stable. A neutron outside of an atomic nucleus decays in a matter of minutes into other particles.

What about protons?
A free proton is a pretty common sight in the cosmos. Much of the ordinary matter (as opposed to dark matter) in galaxies and beyond comes in the form of hydrogen plasma, a hot gas made of unattached protons and electrons. If protons were as unstable as neutrons, that plasma would eventually vanish.

But that isn't happening. Protons — whether inside atoms or drifting free in space — appear to be remarkably stable. We've never seen one decay.

However, nothing essential in physics forbids a proton from decaying. In fact, a stable proton would be exceptional in the world of particle physics, and several theories demand that protons decay.

If protons are not immortal, what happens to them when they die, and what does that mean for the stability of atoms?

—Matthew R. Francis

In Brief

OPTT room name winner and PIP-II meeting room contest

Name this PIP-II meeting room.

Rosa Foote, AD, is the winner of the recent contest to name a conference room for the Office of Partnerships and Technology Transfer. The name of the conference room is now The Enterprise.

It's time to name a third room in the IARC building. This time the subject is the meeting room for the PIP-II suite; see the picture above. The name should reflect invention and innovation.

The contest is open to Fermilab badge holders. The deadline for submissions is Friday, Oct. 30. The winner will be announced shortly afterward.

Email your submissions to Dawn Staszak, and enter "PIP-II conference room naming contest" in the subject line.

Photo of the Day

Great egret

A great egret wades in the pond in front of Wilson Hall. Photo: Jesus Orduna, Brown University

Tip of the Week: Safety

Overheating power strips

Avoid overheating power strips. Check your power strip to be sure that devices are plugged into it correctly.

During lunch on Tuesday, Sept. 22, a multioutlet power strip in the cafeteria of another DOE laboratory burst into flames. This power strip (in the picture above) was being used improperly to supply an ice cream chest freezer in addition to cash register equipment. Power strips damaged by overloads have also been found at Fermilab.

To help avoid this type of incident, the Electrical Safety Subcommittee reminds everyone to ensure that:

High-power loads, such as space heaters and common kitchen appliances, are connected directly to permanent receptacles or a single appliance cord.
The total current of the plugged-in devices adds up to less than the current rating of the strip.
Power strips or extension cords are never plugged into each other (daisy-chained) or run beneath rugs or carpets.
Power strips can be unplugged and removed without using tools or moving heavy furniture.
Power strips have been evaluated for quality construction. The Fermilab Stockroom carries such power strips. Less expensive ones can be found, but they are usually cheaply made and will pose a greater fire hazard.
Power strips that are hot to the touch or show signs of discoloration or melting are unplugged and removed from service.

A power strip should be replaced if:

The NRTL seal, such as UL, ETL or TUV, is missing.
The light is not illuminated when on (if so equipped).
One or more receptacles no longer firmly hold plugs in place.
The power strip is damaged or shows age-related deterioration.
It appears to be a suspect or counterfeit item.

A surge-protected power strip to protect computer equipment or sensitive instruments is also available through the Stockroom.

Arrange your workspace to minimize power strip and extension cord use, or talk to your supervisor about installing additional permanent outlets where needed. Check all electrical equipment, including power strips, for an NRTL label signifying that it has been tested by a qualified independent laboratory. Read all manufacturers' instructions to understand the purposes for which it can and cannot be used. If you are unsure about your power strip, surge protector or outlet strip, contact your supervisor, electrical coordinator or division safety officer.

—Dave Mertz

In Brief

All Experimenters' Meetings resume weekly schedule

With the imminent end of the accelerator shutdown, All Experimenters' Meetings resume their weekly cycle. The next meeting will be in Curia II at 4 p.m. today.

In the News

Where is the cosmic rumble from merging black holes?

From Physics World, Sept. 25, 2015

Astronomers have been left scratching their heads after an international team failed to find evidence for gravitational waves in 11 years' worth of radio-telescope observations. The team had expected to see a modulation in the arrival time of pulsar signals caused by gravitational waves from binary supermassive black holes (SMBHs). The null result could mean that binary SMBHs collapse much faster than previously thought, and therefore spend much less time broadcasting gravitational waves. The result could also provide important information to astrophysicists who are trying to model binary SMBHs.