Question: The Bragg–Gray cavity theory developed by Louis Harold Gray, William Henry Bragg, and a physicist that was a joint winner of the Nobel Prize in Physics in what year?

Context paragraphs:
List of Australian Nobel laureates: Since 1915 there have been sixteen Australian winners of the Nobel Prize.  The majority of these prizes (eight) have been awarded in the field of Physiology or Medicine, and include the second youngest ever laureate (William Lawrence Bragg, who was awarded the prize at 25 years of age).  Bragg and his father (William Henry Bragg) are also the only father-son duo to have won a Nobel Prize in the same year.  Most Australians awarded Nobel prizes before the end of the awarding of British/Imperial honours (in 1992) also received (or were offered) knighthoods.

William Lawrence Bragg: Sir William Lawrence Bragg (31 March 1890 – 1 July 1971) was an Australian-born British physicist and X-ray crystallographer, discoverer (1912) of Bragg's law of X-ray diffraction, which is basic for the determination of crystal structure.  He was joint winner (with his father, William Henry Bragg) of the Nobel Prize in Physics in 1915: ""For their services in the analysis of crystal structure by means of X-ray"", an important step in the development of X-ray crystallography.

Stephen Bragg: Stephen Lawrence Bragg was Vice Chancellor of Brunel University from 1971-81.  He was the son of William Lawrence Bragg and grandson of William Henry Bragg.

North Adelaide Lacrosse Club: The North Adelaide Lacrosse Club was founded on 22 March 1887, and is the oldest continually existing lacrosse club in South Australia.  Nobel Laureate Sir William Henry Bragg, previously a member of the Adelaide Lacrosse Club, was a founding member of North Adelaide as well as the Adelaide University Lacrosse Club later in 1889.  NALC are currently located in the suburb of Gepps Cross.

Adelaide University Lacrosse Club: The Adelaide University Lacrosse Club (AULC) is an Australian-based lacrosse club founded in 1889 by Nobel Prize winning Professor William Henry Bragg.  It is one of the oldest lacrosse clubs in Australia and is a founding member of the Adelaide University Sports Association.  The AULC takes part in an annual competition against the Melbourne University Lacrosse Club that was first contested in 1905 and competes locally in the Lacrosse South Australia competition.  Club membership is focused on University of Adelaide students and graduates.  Other non students are also members.  The AULC trains on the University of Adelaide's Park 10 sports fields in the park lands between the University campus and North Adelaide.

Electoral district of Bragg: Bragg is an electoral district of the House of Assembly in the Australian state of South Australia.  The seat of Bragg is named after the eminent physicists Bragg – William Henry and his son, William Lawrence.  The electorate is largely urban and encompasses a significant portion of the City of Burnside, stretching from the east parklands of Adelaide into the Adelaide Hills.  After a redistribution following the 2006 election, the boundary moved eastwards to include suburbs that had formerly been in the seat of Heysen and now borders Kavel.  Bragg currently includes the metropolitan suburbs of Beaumont, Burnside, Dulwich, Erindale, Hazelwood Park, Heathpool, Kensington Park, Leabrook, Linden Park, Rose Park, Marryatville, Skye, St Georges, Stonyfell, Toorak Gardens, Tusmore, Wattle Park and parts of Glen Osmond, and in the hills it includes Crafers, Cleland, Greenhill, Mount Osmond, Piccadilly, Summertown and parts of Ashton, Basket Range, Carey Gully, Horsnell Gully, Leawood Gardens and Uraidla.

Kedareswar Banerjee: Kedareswar Banerjee (15 September 1900 – 30 April 1975) was an X-ray crystallographer and director of the Indian Association for the Cultivation of Science, Kolkata.  Early in his career he determined the structures of naphthalene and anthracene.  In 1931, he worked with Sir William Henry Bragg and developed one of the first direct methods of crystal structure determination.  He was Professor of Physics at the Indian Association for the Cultivation of Science from 1943 to 1952 and Director of the Association from 1959 until his retirement in 1965.  Between 1952 and 1959 he was Head of the Department of Physics at Allahabad University.  His interests in crystallography were widespread and, with his death, India has lost a renowned teacher.  K. Banerjee joined the research group of Sir C. V. Raman at the Indian Association for the Cultivation of Science (IACS), Calcutta, a premier Indian research institute of India.  He worked in various institutions including IACS, the India Meteorological Department, University of Dhaka and Allahabad University and finally retired as the Director of IACS, Calcutta in 1965.  Prof. Banerjee explained some points of crystal research to Homi J. Bhabha (21 Dec 1956) also .

Bragg peak: The Bragg peak is a pronounced peak on the "Bragg curve" which plots the energy loss of ionizing radiation during its travel through matter.  For protons, α-rays, and other ion rays, the peak occurs immediately before the particles come to rest.  This is called Bragg peak, after William Henry Bragg who discovered it in 1903.

Bragg–Gray cavity theory: According to the Bragg–Gray cavity theory, the ionization produced in a small cavity within an irradiated medium or object is related to the energy absorbed in that medium as a result of its radiation exposure.  It was developed in 1936 by British scientists Louis Harold Gray, William Henry Bragg, and William Lawrence Bragg.

William Henry Bragg: Sir William Henry Bragg (2 July 1862 – 12 March 1942) was a British physicist, chemist, mathematician and active sportsman who uniquely shared a Nobel Prize with his son William Lawrence Bragg – the 1915 Nobel Prize in Physics: ""for their services in the analysis of crystal structure by means of X-rays"".  The mineral Braggite is named after him and his son.  He was knighted in 1920.

Supporting paragraphs: Bragg–Gray cavity theory William Lawrence Bragg
Answer: 1915