CUORE: Creating the coldest cubic meter in the universe

Yale scientists working on the cryostat of the Cryogenic Underground Observatory for Rare Events (CUORE). 

The experiment is located in a clean room deep underneath the Gran Sasso mountain in Italy to shield the experiment from cosmic rays and other environmental backgrounds. 

Credit: CUORE collaboration

The drive to create the coldest cubic meter in the universe may be centered in Italy, but its ultimate success will depend on instruments developed at Yale University.

An international team of scientists recently set a world record by cooling a copper vessel with a volume of a cubic meter down to a temperature of 6 milliKelvins, or -273.144 degrees Celsius.

It was the first experiment to chill an object so large this close to absolute zero.

The collaboration, called CUORE (Cryogenic Underground Observatory for Rare Events), involves 130 scientists from the United States, Italy, China, Spain, France, and other countries.

It is based at the underground Gran Sasso National Laboratory (LNGS) of the Instituto Nazionale di Fisica Nucleare (INFN), in Italy.

"This is a major technological achievement," said Karsten Heeger, a professor of physics at Yale and director of Yale's Arthur W. Wright Laboratory.

CUORE is part of the new experimental program in neutrinos and dark matter pursued at the Wright Lab.

Yale physicists are building and testing instrumentation that will be used at temperatures of 10mK in the experiment's cryostat, which is the chilled chamber.

Reina Maruyama, an assistant professor of physics, is one of the original proponents for the US involvement in CUORE and is a coordinator of its data analysis

"In collaboration with the University of Wisconsin, we have developed a detector calibration system that will deploy radioactive sources into the coldest region of the cryostat and characterise our detectors," Heeger said.

Once the CUORE experiment is fully operational, it will study important properties of neutrinos, the fundamental, subatomic particles that are created by radioactive decay and do not carry an electrical charge.

Specifically, the experiment will look at a rare process called neutrino-less double-beta decay.

The detection of this process would let researchers demonstrate, for the first time, that neutrinos and anti-neutrinos are the same, thereby offering a possible explanation for the abundance of matter, rather than anti-matter, in the universe.

The experiment uses heat-sensitive detectors that operate in extremely cold temperatures. "It poses a unique challenge," Heeger said.

"We are trying to detect a minuscule amount of heat from nuclear decay, but need to know this very precisely. The detector calibration will tell us if we see the heat from double-beta decay or environmental backgrounds."

Now that the cryostat has reached base temperature, the commissioning and cryogenic testing of the calibration system will take place in the next few months, Heeger said.

More information: crio.mib.infn.it/wigmi/pages/cuore.php

NASA CAL: Creating the Coldest Spot in Universe on the Space Station

The icy chill of empty space will soon be trumped by the temperatures aboard the International Space Station.

Using NASA's Cold Atom Lab (CAL), scientists plan to reach temperatures only a few degrees above absolute zero on the station, allowing them to study challenging aspects of quantum mechanics.

"We're going to study matter at temperatures far colder than are found naturally," JPL's Rob Thompson said in a statement.

Thompson is the Project Scientist for the Cold Atom Lab (CAL), an atomic 'refrigerator' planned to make the orbiting laboratory its new home in 2016.

He said, "We aim to push effective temperatures down to 100 pico-Kelvin"—one ten billionth of a degree above absolute zero.

NASA's Cold Atom Laboratory utilizes a magnetic trap that confines particles, allowing them to cool to temperatures just barely above absolute zero. Credit: NASA/Jet Propulsion Laboratory

When atoms of rubidium and sodium reach temperatures near absolute zero, they, they behave as both particles and waves, merging into a single wave of matter.

Known as Bose-Einstein Condensates (BCEs), the new material was predicted by both Albert Einstein and Satyendra Bose in the early 20th century.

Mixing two BCEs isn't like blending ordinary gases — the condensates instead behave like waves, interfering with one another so that two atoms combined together can result in no atom at all.

"The Cold Atom Lab will allow us to study these objects at perhaps the lowest temperatures over," Thompson said.

Researchers will also be able to mix super-cool atomic gases on board the space station.

Atoms will float free of perturbations, which will allow for extremely sensitive measurements of the weak interactions that occur.

"This could lead to the discovery of interesting and novel quantum phenomena," Thompson said.

The International Space Station is a prime location to perform such experiments because of lack of interference from the pull of gravity.

A basic principle of thermodynamics is that gas cools as it expands. When gas is sprayed from a household aerosol can, the can cools because the remaining gas within it expands to fill the recently-vacated space.

NASA Cassini Imaging: Creating An Epic Picture of Earth from Saturn

This simulated view from NASA's Cassini spacecraft on July 19, 2013, shows the expected positions of Saturn and Earth around the time Cassini is taking Earth's picture.

On July 19, 2013, NASA's Cassini spacecraft will be turned to image Saturn and its entire ring system during a total eclipse of the sun, as it has done twice before during its previous 9 years in orbit.

But this time, the images that will be collected have been specifically designed for something very special.

They will capture, in natural colour, a glimpse of our own planet next to Saturn and its rings, during an event that will be the first time Earthlings know in advance their picture will be taken from a billion miles away.

'It will be a day', says Cassini imaging team leader, Carolyn Porco of the Space Science Institute in Boulder Colorado, 'for all the world to celebrate.'

'Ever since we caught sight of the Earth among the rings of Saturn in September 2006 in a mosaic that has become one of Cassini's most beloved images, I have wanted to do it all over again, only better', said Porco.

'And this time, I wanted to turn the entire event into an opportunity for everyone around the globe, at the same time, to savour the uniqueness of our beautiful blue-ocean planet and the preciousness of the life on it.'

Porco was involved in co-initiating and executing the famous "Pale Blue Dot" image of Earth taken by NASA's Voyager 1 from beyond the orbit of Neptune in 1990.

"While Earth will be only about a pixel in size from Cassini's vantage point 898 million miles [1.44 billion kilometers] away, the Cassini team is looking forward to giving the world a chance to see what their home looks like from Saturn," said Linda Spilker, Cassini project scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif.

"With this advance notice, we hope you'll join us in waving at Saturn from Earth, so we can commemorate this special opportunity."

The intent for the upcoming mosaic is to capture the whole scene, Earth and Saturn's rings from one end to the other, in those particular camera filters - red, green and blue—that can be composited to form a natural color view, or what human eyes might see at Saturn.

It also includes imaging the Earth and the Moon with the high resolution camera, something not yet done by Cassini.

Three years ago, Porco and her staff members at CICLOPS began carefully examining Cassini's planned trajectory for the remainder of its Saturn mission in search of the best time to image the Earth when it was unobstructed by Saturn or its rings, and when there weren't other pressing scientific observations that rendered the idea impossible.

Imaging any planetary body close to the sun necessitates doing so when the sun is completely blocked, so that no undiluted sunlight can enter the cameras or other Cassini instruments and damage their sensitive detectors. Such opportunities during Cassini's orbital tour are rare.

When all was considered, the best time for this event was found on July 19, 2013. For several hours on that day, the spacecraft was once again going to be in Saturn's shadow as a result of the planning work of the project's rings working group and the spacecraft team.

The intent was to duplicate the eclipse geometries from earlier in the mission to collect, for scientific purposes, both visible and infrared imagery of the planet and its ring system.

Grabbing the chance to image the Earth within the mosaic of scientific images already being planned by both the imaging and infrared mapping teams involved special care and a lot of work to ensure a mosaic without gaps and an unobscured image of the Earth without the overwhelming glare from nearby rings.

It was a big challenge and turned into a fine example of teamwork.

'My colleagues on the VIMS team were great sports about it, and allowed us to tweak their mosaic to find the best placement of mosaic images and the best times for the high resolution Earth images', said Porco.

'In the end, we all got what we wanted.' Unlike previous images of Earth by NASA interplanetary spacecraft since the days of Voyager, this will be the first time that the world's people will know ahead of time that their picture is being taken.

Porco is hoping for a memorable event.

'My sincere wish is that people the world over stop what they're doing at the time the Earth picture is taken to revel in the sheer wonder of simply being alive on a pale blue dot of a planet, and to appreciate the ever-widening perspective of ourselves and our world that we have gained from our interplanetary explorations.

We are dreamers, thinkers, and explorers, inhabiting one achingly beautiful planet, yearning for the sublime, and capable of the magnificent.

Let's celebrate that, and make this one day a day the whole Earth smiles in unison.'

Cassini's images of Earth, both wide angle and narrow angle, will be captured between 21:27 to 21:42 on July 19 UTC, or 14:27 and 14:42 PDT.

During these times, North America and part of the Atlantic ocean will be in sunlight. The illuminated parts of the Earth and the Moon will each be no more than one pixel across.

Graphics illustrating the position of Earth with respect to Saturn and its rings, and the part of the Earth viewable during this event are available at: http://ciclops.org/view_event/193, http://saturn.jpl.nasa.gov/waveatsaturn, and http://www.nasa.gov/cassini