Mysterious, never-before-seen signals have been captured by the new gravitational wave detector

0
21


tabletop gravity wave The detector based on a piece of resonant quartz recorded two mysterious signals in the first 153 days of operation.

It is unclear exactly what these signals are. They can be from a number of phenomena. But one of these phenomena is exactly what the detector is designed to capture – high-frequency gravitational waves, which have not been recorded before.

It’s too early to draw any conclusions, but the next iteration of the detector will be able to narrow down the cause of quartz’s resonance.

“It’s exciting that this event showed that the new detector is sensitive and gives us results, but now we have to determine exactly what those results mean,” Physicist Michael Tobar from the University of Western Australia.

“Through this work, we have shown for the first time that these devices can be used as highly sensitive gravitational wave detectors.”

The first pioneering detection of gravitational waves was made just six years ago. Since then, the LIGO and Virgo detectors have continued to reveal that the universe is ringing with previously hidden gravitational waves, as a result of collisions between black holes and neutron stars.

These detectors are huge and with arms 4 kilometers (2.5 miles). The laser beams along these arms are precisely disrupted by the gravitational waves produced interference patterns in recombined light that can be analyzed to reveal the nature of the event that caused the waves. So far, the technology has been improved for the low frequency system.

High-frequency gravitational waves are hard to detect, but they’re definitely worth a look. The wavelength of gravitational waves is proportional to the size of the universe. Those that occur later are larger, so high-frequency waves may reveal information about the great explosionAnd the universe in the beginning of time.

Sources of high-frequency gravitational waves in the recent past could include virtual objects such as bosons and primordial black holes. These waves can even be produced by pulling dark matter. So astronomers will be deeply interested in discovering these signals.

Tobar and fellow physicist Maxim Goryachev of the University of Western Australia designed a tabletop detector for high-frequency gravitational waves. in 2014. Now, along with an international team, they’ve conducted observational tours.

The detector itself is a disc of quartz crystals, called a sound wave (BAW) resonator, with one side slightly convex. Theoretically, high-frequency gravitational waves should generate static sound waves in the disk, which are trapped as phonons by the convex side.

The disc is cooled by cooling to reduce thermal noise, and conductive plates placed at very small distances from the crystal pick up the tiny piezoelectric signals generated by the acoustic modes in which they vibrate. This signal is very small, so a superconducting quantum interference device, or SQUID, is used to act as a highly sensitive signal amplifier.

The entire detector is placed in a vacuum chamber that is shielded from radiation to prevent as much interference as possible. With this setup, the team conducted two monitoring rounds, and did detection during each round – the first on May 12, 2019, and the second on November 27, 2019.

Now, there are a number of reasonable possibilities here. mechanical stress relaxation within a single quartz disk; An internal radioactive event caused by external ionizing radiation is another event, although researchers do not know any external event that could have caused this.

Similarly, although a meteor shower It can produce sound waves, the shielding should protect the device from these waves. The culprit may be cosmic rays.

Other options are more exciting — perturbations caused by topological defects in dark matter, or massive dark matter particles, could theoretically cause the signals.

Or, finally, there is the possibility of high-frequency gravitational waves. This will require further investigation, as the shape of the signal does not display the “chirp” property of cosmic fusion.

In the next iteration of the detector, researchers will add a second crystal, with its own squid and readings, along with the muon detector to exclude cosmic rays. This should help narrow the range of signals the team detected.

“This experiment is one of only two experiments currently active in the world that search for high-frequency gravitational waves at these frequencies, and we have plans to extend our reach to higher frequencies, where no other experiments have been investigated before,” Tobar said.

“The development of this technique will potentially provide the first detection of gravitational waves at these high frequencies, giving us new insight into this area of ​​gravitational wave astronomy.

“The next generation of the experiment will involve building a version of the detector and a muon detector that is sensitive to cosmic particles. If two detectors find the presence of gravitational waves, that would be really exciting.”

The search was published in physical review messages.





LEAVE A REPLY

Please enter your comment!
Please enter your name here