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# Pressure & vacuum metrology

### A Primary Standard for Measuring Vacuum

A novel, quantum-based vacuum gauge system invented by researchers at the National Institute of Standards and Technology (NIST) has passed its first test to be

### No Longer Under Pressure: NIST Dismantles Giant Mercury Manometer

Video by: Jennifer Lauren Lee/NIST. Animations: Sean Kelley/NIST. Music: Blue Dot Sessions. Photos: Bruce Johnson and Jay Hendricks/NIST For the last 30 years

### FLOC Takes Flight: First Portable Prototype of Photonic Pressure Sensor

In collaboration with industry, researchers from the National Institute of Standards and Technology (NIST) have made the first portable prototype of the Fixed

## Publications

### A constant pressure flowmeter for the extremely high vacuum

Author(s)
Stephen Eckel, Daniel Barker, James A. Fedchak, Emmanuel Newsome, Julia Scherschligt, Robert E. Vest
We demonstrate operation of a constant-pressure flowmeter capable of generating and accurately measuring flows as low as $1\times10^-13}$mol/s. Generation of

### Emerging technologies in the field of thermometry

Author(s)
Zeeshan Ahmed, Graham Machin, Sergey Dedyulin
The past decade saw the emergence of new temperature sensors that have the potential to disrupt a century-old measurement infrastructure based on resistance

### Capability of commercial trackers as compensators for the absolute refractive index of air

Author(s)
Patrick Egan
A procedure is presented which calibrates a commercial wavelength/refractive-index tracker, so that it can compensate for the absolute refractive index of air

### Progress towards comparison of quantum and classical vacuum standards

Author(s)
Daniel Barker, Nikolai Klimov, Eite Tiesinga, James A. Fedchak, Julia Scherschligt, Stephen Eckel
We present our progress towards a comparison of NIST's cold atom primary vacuum standard and a dynamic expansion vacuum standard. The cold atom vacuum standard