Stars more than eight times the mass of our Sun eventually collapse under their own weight, and may explode into spectacular supernovae. The temperatures and pressures generated in these events are so intense they create a large burst of particles called neutrinos, which eventually reach Earth.
Now, Cecilia Lunardini at Arizona State University and RIKEN BNL Research Center in Upton, USA, has calculated that lots of neutrinos may also reach Earth from ‘failed supernovae’—huge stars that collapse without exploding to produce black holes1.
The neutrino contribution from these failed supernovae could greatly increase the total flux of neutrinos reaching Earth from millions of collapsing stars throughout the universe. Lunardini calls this total the ‘diffuse supernova neutrino flux’.
“In the diffuse flux, the contribution of each supernova is very small, but the total is detectable,” she says. “We only need to reach the right experimental sensitivity to start detecting it.”
Unfortunately, neutrinos are notoriously difficult to detect because they barely interact with other matter. One of the world’s best detectors is the Super-Kamiokande (‘Super-K’) neutrino observatory, situated in a mine beneath Gifu prefecture Japan, and even it requires 50,000 tons of ultra-pure water to scatter the neutrinos.
Lunardini decided to calculate whether a device like Super-K could detect neutrinos from supernovae collapsing into black holes.
“The idea that neutrinos are emitted in black-hole-forming collapses is not new,” she says. “The novelty of my work is in showing that these neutrinos can build up to a significant diffuse flux, thus adding to the flux from successful supernovae.”
In fact, Lunardini calculated that the Earth may receive up to one neutrino per square centimeter per second from failed supernovae. This is even more than the flux from successful supernovae, but probably beyond the detection limit of Super-K.
There is growing support in the scientific community to build larger, more sensitive neutrino detectors containing up to a million tons of water. Once these bigger detectors are built, Lunardini thinks it is only a matter of time before the diffuse neutrino flux can be measured. The results could reveal some fascinating new physics.
“[Failed supernovae] are very difficult to study with telescopes due to the fact that they do not explode but just disappear from the sky without much emission other than neutrinos,” says Lunardini. “The possibility to get information on these objects—even just to test their presence and how many there are in the universe—with neutrinos is exciting.”
1. Lunardini, C. Diffuse neutrino flux from failed supernovae. Physical Review Letters 102, 231101 (2009).
The corresponding author for this highlight is based at the RIKEN BNL Research Center Theory Group
OU-led team discovers rare, newborn tri-star system using ALMA
27.10.2016 | University of Oklahoma
First results of NSTX-U research operations
26.10.2016 | DOE/Princeton Plasma Physics Laboratory
Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.
This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
27.10.2016 | Materials Sciences
27.10.2016 | Physics and Astronomy
27.10.2016 | Life Sciences