At 8.15am on 6 August 1945 the lives of Setsuko Morita, her husband, Noboru, and those of everyone they knew changed forever. They were school pupils in Hiroshima, both freed from study to work in the fields on Japan's wartime food production, at the moment the Enola Gay dropped the atomic bomb on their city.
Their portraits are among those of 65 survivors in a London exhibition opening tomorrow, including those of a woman and her baby who are third and fourth-generation Hibakusha – literally bomb-affected people – and a man who was just a foetus in his mother's womb on August 6 1945 and who is too embarrassed to use his survivor's card. It is the first time the portraits have been seen outside Japan.
The Moritas, explained Setsuko, are quiet people who married when they were 18 but "were never fortunate enough to have the blessing of children" – almost certainly as a result of injuries she suffered that day. They have come to London driven by the same urge which created the exhibition – to bear witness to what happened so that it will never happen again.
Setsuko Morita managed to stagger home after the bombing with 25% burns, through roads where every building was gone, crowded with people bearing terrible injuries, pleading for water. Her parents treated her for a week with three buckets of sterilised water and baby powder until they finally got her to a doctor. She overheard a conversation in which her mother said it would be better if she died, while her father argued that her life might still be worth living.
Noboru, meanwhile, spent the next three months working in his school, just beside his family home, which became a hospital, morgue, crematorium and cemetery. He watched many people die in what had been his classroom, begging for water. He spent most of every day searching for wells and springs because the mains had been destroyed and the river was choked with wreckage and bodies.
The portraits are by Professor Hideo Ohya, a renowned artist in Japan, and by colleagues and postgraduate students at Hiroshima city university. A postwar baby, it was only when he moved from Tokyo to head the art faculty that he realised how limited his understanding of the fate of the city had been. As he began to meet survivors he realised that the youngest were approaching old age and there would soon be no first-hand witnesses. Gradually members of the university staff came forward, volunteering to have their own portraits included. Many in the city have hidden their status as a badge of shame that still attracts fear of contamination.
The exhibition has come to London through Paul Stafford of Kingston university, who found them almost unbearably moving even though none show obvious disfigurement. He saw the portraits as a way of fostering links between the two institutions.
The Brunei gallery at the School of Oriental and African Studies in Russell Square, which has a Japanese garden on the roof where a private ceremony will be held to mark the exact time of the atomic bomb explosion, proved the perfect space for the exhibition.
Like many of those portrayed, Noboru Morita looks remarkably calm and cheerful – but that is one of the side effects he bears. He has been on anti-depressants for 20 years to calm his growing dread of cancers and other long-term effects suffered by many of the survivors. He felt angry for years, baffled and even resentful of his own survival, never speaking of them but deeply affected by the scenes he witnessed.
His wife, in her portrait as in life, looks tranquil and immaculate. Only when she pushes back her sleeves do the streaks of white scars along the outside of one arm and the inside of the other show.
The Light - portraits of the Hibakusha, Brunei Gallery, London, free, until 8 October
Portrait profiles
A mother holding her baby symbolises the generations affected by the Hiroshimo bombing. Born in 2007 and aged just one in this portrait, the boy is a third-generation atomic bomb survivor on his father's side and a fourth-generation survivor on his mother's.
"Children are the lights that connect us to the future, they are hope and the joy of being alive. I hope peace will last, for the sake of our children," his mother says. His grandmother and great-grandparents are also part of the project.
Painted by Hideo Ohya, professor of art at Hiroshimo city university and creator of the project, Setsuko Morita was 13 at the time of the bombing. On returning home her parents tended to her burns with rationed ointment. She married fellow survivor, Noboru, at the age of 18 and believes strongly in speaking about her experiences. She has re-counted them at schools in Japan and New York.
Walking with his mother towards the family field, Noboru Morita was 13 when the atomic bomb exploded. Noboru helped to care for the injured at the refuge set up at the school behind his half-demolished home.
He moved away after marrying Setsuko but returned to the city at the age of 55. Keeping his survivor status a secret for many years he has, through the encouragement of his wife, gradually become able to speak about his experiences.
Ami Sedghi