Ambient office = 102 nanosieverts per hour

Ambient outside = 97 nanosieverts per hour

Soil exposed to rain water = 99 nanosieverts per hour

Crimini mushrooms from Central Market = 125 nanosieverts per hour

Tap water = 111 nanosieverts per hour

Filter water = 102 nanosieverts per hour

Part 2 of 2 Parts (Please read Part 1 first)
     The type of nuclear reaction that fuels current commercial nuclear power plants is nuclear fission which is the splitting of heavy atomic nuclei. Nuclear fusion forces atoms of very light elements together to create heavier elements. This produces a huge amount of energy. Decades have been spent looking for a way to create efficient fusion reactions. However, it turns out that creating controlled fusion reaction on Earth is very difficult to control. To date, no fusion experiment has produced more energy than was required to get the reaction going.
     While the latest experiment at the NIF still required more energy going in than it got out, it is the first to reach the crucial stage of ‘ignition’, which produced considerably more energy that ever before. This paves the way for ‘break even’ which is where the energy going in is equal to the energy coming out.
     In many of the inertial confinement experiments, the fuel pellets contain deuterium and tritium which are heavy isotopes of hydrogen. These nuclei are the easiest to fuse and produce the most energy. The fuel pellets have to be heated and compressed to match the condition at the center of the Sun, which is a natural fusion reactor.
     Once these conditions are reached, fusion reactions release several types of particles, including ‘alpha’ particles which interact with the surrounding plasma and increase the heat. The heated plasma then produces more alpha particles and so on, in a self-sustaining reaction. This is referred to as ignition. However, this process has never been achieved before. The results from the NIF experiment on August 8th indicated an energy output of over one mega-joule which marks the threshold agreed upon by the fusion research community for ‘ignition’. It was six times the previous highest energy achieved.
     Arthur Turrell is in the Department of Physics at Imperial College. He just published a book titled The Star Builders: Nuclear Fusion and the Race to Power the Planet. He said that “This phenomenal breakthrough brings us tantalizingly close to a demonstration of ‘net energy gain’ from fusion reactions—just when the planet needs it. The team at the National Ignition Facility, and their partners around the world, deserve every plaudit for overcoming some of the most fearsome scientific and engineering challenges that humanity has ever taken on. The extraordinary energy release achieved will embolden nuclear fusion efforts the world over, lending momentum to a trend that was already well underway.”
     Professor Chittenden said that “while the NIF is primarily a physics experiment and does not have the main goal of creating fusion energy, this incredible result means that this dream is closer to being a reality. We have now proven it is possible to reach ignition, giving inspiration to other laboratories and start-ups around the world working on fusion energy production to try to realize the same conditions using a simpler, more robust and above all cheaper method.”
     The team at Imperial is now analyzing the data from the NIF experiment. They are using diagnostic methods that they have created in order to comprehend what is happening in such extreme conditions. Dr. Brian Appelbe is a Research Associate at the CIFS at Imperial. He said that “the NIF lasers already created the most extreme conditions on Earth, but the new experiment appears to have doubled the previous temperature achieved. We have entered a regime we’ve previously never been in—this is uncharted territory in our understanding of plasma.”
      Dr. Aidan Crilly is also a Research Associate at the CIFS at Imperial. He added that “reproducing the conditions at the center of the Sun will allow us to study states of matter we’ve never been able to create in the lab before, including those found in stars and supernovae. We could also gain insights into quantum states of matter and even conditions closer and closer to the beginning of the Big Bang—the hotter we get, the closer we get to the very first state of the Universe.”

Ambient office = 106 nanosieverts per hour

Ambient outside = 82 nanosieverts per hour

Soil exposed to rain water = 84 nanosieverts per hour

Blueberry from Central Market = 80 nanosieverts per hour

Tap water = 130 nanosieverts per hour

Filter water = 122 nanosieverts per hour

Part 1 of 2 Parts
     There is a great deal of research going in the field of nuclear fusion. If the conditions inside the Sun can be duplicated on Earth, humanity will have an inexhaustible cheap source of clean energy with no release of carbon dioxide or long-lived radioactive waste. Many of the research projects are based around a Soviet invention called a tokamak. Others are working with stellarators which are similar. Both of these approaches are based on using super powerful magnets to compress and heat a plasma.  A totally different approach is called inertial confinement. Inertial confinement fusion is technology that attempts to initiate a nuclear fusion reaction by heating and compressing a fuel target which is typically a pellet. Powerful lasers are used to vaporize the pellet.
      A new experiment at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory has achieved fusion ignition. This experiment produced more energy than any previous inertial confinement fusion experiment. The experiment proves that fusion ignition is possible with this approach. It is paving the way for reactions that produce more energy than they consume.
     Physicists at Imperial College London are helping to analyze the data generated by the successful experiment which was conducted on the 8th of August, 2021. Twenty four Ph.D students from the Imperial College have gone on to work at the NIF. The College maintains strong links with the NIF and other such laboratories throughout the world connected by the Center for Inertial Fusion Studies (CIFS). 
     Professor Jeremy Chittenden is a Co-director of the CIFS at Imperial. He said that “demonstration of ignition has been a major scientific grand challenge since the idea was first published almost 50 years ago. It was the principal reason for the construction of NIF and has been its primary objective for over a decade.”
     “After ten years of steady progress towards demonstrating ignition, the results of experiments over the last year have been more spectacular, as small improvements in the fusion energy output are strongly amplified by the ignition process. The pace of improvement in energy output has been rapid, suggesting we may soon reach more energy milestones, such as exceeding the energy input from the lasers used to kick-start the process.”
     “This is crucial for opening up the promise of fusion energy and allowing physicists to probe the conditions in some of the most extreme states in the Universe, including those just minutes after the Big Bang. Controlled fusion in the laboratory is one of the defining scientific grand challenges of this era and this is a momentous step forward.”
     Professor Steven Rose is a Co-director of the CIFS at the College. He said that “the NIF team have done an extraordinary job. This is the most significant advance in inertial fusion since its beginning in 1972. What has been achieved has completely altered the fusion landscape and we can now look forward to using ignited plasmas for both scientific discovery and energy production.”
Please read Part 2 next

Ambient office = 98 nanosieverts per hour

Ambient outside = 73 nanosieverts per hour

Soil exposed to rain water = 70 nanosieverts per hour

Watermelon from Central Market = 77 nanosieverts per hour

Tap water = 108 nanosieverts per hour

Filter water = 91 nanosieverts per hour

Part 2 of 2 Parts (Please read Part 2 first)
     The record plasma generated by the Wendelstein 7-X has now been analyzed in high detail. At high plasma temperatures and low turbulence losses, the usual stellarator magnetic ripple losses in the energy balance could be observed. They accounted for about thirty percent of the heating power, which is a considerable part of the energy balance.
      The effects of magnetic optimization of the Wendelstein 7-X can now be shown by a thought experiment. It was assumed that the same plasma values and profiles that led to the record result of the Wendelstein 7-X were also achieved in reactors with a less optimized magnetic field. The magnetic ripple losses that were expect were calculated. They would be greater than the input heating power which is physically impossible. Professor Per Helander is the head of the Stellarator Theory Division at IPP. He said that “This shows that the plasma profiles observed in Wendelstein 7-X are only conceivable in magnetic fields with low magnetic ripple losses. Conversely, this proves that optimizing the Wendelstein magnetic field successfully lowered the magnetic ripple losses.”
     However, the plasma discharges in the Wendelstein 7-X have been very short so far. To test the performance of the Wendelstein design in continuous action, a water-cooled wall cladding is being installed. Equipped with this new cooling system, the researchers will gradually extend the plasma time up to thirty minutes. Then it will be possible to check whether the Wendelstein 7-X can also fulfill its optimization goals in continuous operation.
     The aim of fusion research is to develop a climate and environmentally friendly power plant. Similar to the sun, the intent is to generate energy from the fusion of light atomic nuclei. Because the fusion reaction will only ignite at temperatures above one hundred million degrees, the low-density hydrogen plasma fuel must not come into contract with the cold walls of the containment vessel. Held by magnetic fields, the plasma floats almost contact free inside the vacuum chamber.
     The magnetic cage of the Wendelstein 7-X is created by a ring of fifty superconducting magnetic coils. Their special shape is the result of sophisticated computer optimization calculations. With their help, the quality of plasma confinement in a stellarator should be able to reach the level of the competing tokamak-type facilities.
     There are dozens of organizations working on the development of viable commercial nuclear fusion power plants. Over twenty private companies are involved in the research. Many different designs are being explored as are many different types of fuels. Tokamaks were invented by Soviet physicists in the 1950s and are the basis of some of the biggest nuclear fusion projects currently underway. Stellarators were actually invented before tokamaks in 1951 by Lyman Spitzer in 1951. Work on tokamaks and stellarators has been carried out for decades with slow progress. Now there is a sort of fusion race and there are many other designs competing with tokamaks and stellarators. Despite their long history, tokamaks and stellarators may wind up being a dead end as other, more recent designs surpass their performance.
Magnetic field configuration for the Wendelstein 7-X fusion reactor.