Project Manhattan

"Now I am become death, the destroyer of worlds.” -Robert J. Oppenheimer

Los Alamos County, New Mexico, United States, the birth place of the atomic bomb cracked the atom and ushered the humanity to a new age, ending the world war Ⅱ. Major General Leslie Groves of the U. S, Army Corps of Engineers along with the nuclear physicist Dr. Robert J. Oppenheimer the director of the Manhattan project pioneered, the construction of the first atomic bomb “Trinity”.

In 1939, the project began, with 130,000 employes at its peak, cost of US $2 billion produced the unthinkable. 16th of July 1945, at 5.29 a.m., a ball of fire as bright as the sun, a sudden wave of heat, a mushroom cloud of over 12 km rose over the site with a tremendous roar passing through the valleys; creating extraordinary scenes.

“Gadget” a spherical device, about 6 kg Plutonium (239 Pu), the fizzle material kept in its sub critical mass was brought to its super critical mass by compressing the core of Plutonium by the explosion of the conventional bombs placed in the spherical structure. A neutron chain reaction begins, producing an avalanche of neutrons, persuading the huge destruction via the fission reaction. Urchin initiator, a small ball of the size of bead, made of Polonium-Beryllium was placed inside the two hemispheres of the plutonium core. Placed at a height 30 m, held together by wires, the bomb was detonated yielding an equivalent of 20,000 T of TNT. At the moment of the explosion, temperature reached about 1 million Kelvin inside the bomb of which the fission process only takes a fraction of a second. Ultra violet rays are initially ignited and followed by light rays in the visible range ones it reaches a temperature as hot as the sun surface of the sun.

Manhattan project, undoubtedly the result to end the world war Ⅱ.

The Trinity test showcased the ability to produce atomic bombs. The 6th and 9th of August 1945, was a dark patch to the entire human race as “Little Boy” made of Uranium 235 and “Fat Man” made of Plutonium 239 were dropped at Hiroshima and Nagasaki in Japan killing thousands of innocent. Dr. Robert J. Oppenheimer himself quoted from the sacred Hindu scripture, the Bhagvard Gita; “Now I am become death, the destroyer of worlds.” after the tragedy in Japan.

After, the detonation of the atomic bombs, Oppenheimer himself took measures to control the production of atomic bombs and expressed his view against the construction of hydrogen bombs because of the adverse effects. At present, measures are taken in order to ensure safety of nuclear materials and use heavy elements to the betterment of the world.

Written by: Buddheen Perera

Poster Design by: Sahan Wijethunga

The structure of the center is such, two source frames, 28 modules and an staggering 1180 source pencils can be accumulated at the highest possible activity but a total of 52 source pencils are installed at the present activity, while the other pencils remains dummy pencils. BC-188 Co-60 pencils made with inner slug capsule Ziracalloy-2 and outer encapsulation SS-316L of dimensions 11.1 mm × 451 mm are embedded within the two frames. Moderation of the source is operating via a tank of water which has a capacity of 72,000 l for the maximum activity of 3000kCi. Cherenkov radiation, a phenomenon that occurs when a charged particle passes through a dielectric medium at a speed greater than the phase velocity of light in that medium is observed. It results in the emission of electromagnetic radiation, primarily in the ultraviolet and visible light spectrum, creating a characteristic blue glow. The gamma irradiator is a category 4 panoramic, wet storage gamma irradiator. There had been three source loadings of 250 kCi, 125 kCi and 250 kCi in 2014, 2017 and 2021 respectively. The present activity is collectively around 300 kCi separated to the small and large frames operating at 24 × 7 hours basis with an employ count of 24. A total of 40 boxes are used to store the products to be irradiated. Daily, the cycle time and the factors that change due to the decaying of the source is calibrated in the control room. Radiation safety and security is optimum to ensure safeguard of the radiation workers and the general public. A safety interlocked personal access door which can be directly observed by the position of the hydraulic jack, a pull-out station, vacuum chamber to put out the ozone gas trapped inside after the source is lowered down to the moderator, temperature sensors and even an emergency cable in case of an emergency are featured in the irradiation center for safety. The source transport is carried out with high security, the help of the Special Task Force because of the danger of radiation and the source falling to the hands of people who would use it misleadingly creating a huge damage. The STF-Katukurunda (National Radiological Security Event Monitoring Center) and remote monitoring centers closely monitor all the activities with in the SLGC to ensure complete safety.

Gamma irradiation applications are widely spread in sterilization of medical products, sterilization of packaging material, cosmetics etc., Microbial disinfestation and medicinal herbs and insect control in food, sprout inhibition, phyto-sanitary treatments (quarantine treatments), mutation breeding, material modification and sterile insect technique for disease control. It is a reliable and safe method with no contamination and is non-toxic. Treated product is usable immediately, a turning point over other conventional methods.

Sri Lanka Gamma Centre will serve the country in years to come with the maximum source activity to uplift the economy of the country and releasing quality, user friendly products for the entire community.

Radiation, a force to be reckoned with, but one we can harness for the benefit of mankind!

Written by: Buddheen Perera

Designed by: Sahan Wijethunga