Leslie Hodson: Particle physicist and pioneer in the study of cosmic rays

Leslie Hodson was an experimental particle physicist who developed cloud- and spark-chamber techniques in the study of cosmic rays.

Yet despite his achievements in the field, he believed that the most useful thing he did was prevent asbestos from being used in the construction of the new campus at Leeds University in the 1960s.

Albert Leslie Hodson was born an only child in 1925 to tenant farmer parents at Fishlake, north-east of Doncaster. He first attended Fishlake Endowed School, a two-room school where children of all levels were taught together. He failed his 11-plus but despite this, his father found him a place at Thorne grammar school, at a cost of three guineas a term, and his parents managed to scrimp enough to pay for it.

In 1943, Hodson's higher school certificate results were good enough for a county scholarship. He decided to study physics at Manchester University, having heard from a cousin that Professor P.M. Blackett was working there. Leslie had never heard of Blackett, but what had impressed his cousin was good enough for him. After two years he was recruited to the Royal Aircraft Establishment at Farnborough, but the week he was due to report he developed mumps. The war ended, and instead of going to Farnborough he completed his third year at Manchester.

During this year he devised his own project on the optics of sodium vapour using equipment of his own construction. Blackett immediately offered him a PhD researching cosmic rays.

He studied altitude effects in cosmic ray air-showers. This involved building his own instruments, including making Geiger counters from glass tubing and fitting them into bomb casing. This instrument package was loaded into the bomb bay of a Mosquito and flown to over 30,000ft. The solution to a problem in the use of Geiger tubes led to his first scientific paper at only 23.

The mainstay of Blackett's cosmic-ray research was the cloud chamber. He had received the Nobel Prize in 1948 for his work on triggering chambers using external Geiger counters and the subsequent discovery of the positron. In a flash of inspiration, Hodson realised that the trigger could be generated from the gas within the chamber itself. Despite others' doubts, he persuaded Blackett to support him. He also built the electronics to control the chamber, secretly automatically, out of hours, hiding his prototype from Blackett under a cover and only revealing it when it was fully working. As a result, Manchester appointed him assistant lecturer.

In 1951 he became a research associate at Princeton. The Princeton cosmic-ray group was running cloud chambers at Echo Lake in the Rockies at an altitude of 3,230m. They were studying the so-called V-particles, recently discovered at Manchester. All the images were photographed and, on the last reel of film they discovered a new particle, now known as the K+, one of the kaons. Their measurement of the particle's rest mass was within two per cent of the currently accepted figure.

Hodson returned to Britain in 1954 to take up a lectureship at Leeds University. He designed and built the world's largest cloud chamber, having taught himself the required skills, and made deft use of local industry in its construction.

The mid-Sixties were a period of expansion in the universities, and Leeds had chosen Chamberlin, Powell and Bon to design a new campus. Leslie worked with them, providing a link between the architectural vision and the scientists and educators who were to use the buildings. The design called for asbestos cement panels as duct covers; Hodson had read in the scientific press that asbestos was hazardous and fought against its use. The University banned the use of asbestos in all future buildings, probably the first time this was done in Britain.

By the end of the 1960s the physics department was installed in its elegant modernist buildings and Hodson could turn once again to research. The quark model had been proposed by Murray Gell-Mann and George Zweig in 1964 and physicists were looking for evidence of them. Using the Leeds cloud chamber, he and his team searched for free quarks in the cores of cosmic ray air-showers. Quarks were predicted to have one-third or two-thirds the charge of an electron and this would give rise to one-ninth or four-ninths the ionisation along their path. This would be clearly visible by the thickness of the tracks produced in a cloud chamber. However, the cores of cosmic ray air-showers have vast numbers of particle tracks, all of which had to be examined in detail. It was painstaking work and at the end of it Hodson and his team came to the conclusion that there was no evidence that free quarks existed.

The visual and photographic techniques Hodson used were labour-intensive and expensive; towards the end of his career this became a seriously limiting factor. Recent experiments replaced the cameras with electronic techniques using charge read-out from vast numbers of wires and strips. However, now in an era where high-resolution digital photography is cheap and the computer power to process it ubiquitous, a return to visual and photographic techniques offers simplicity and elegance, and a further reduction in cost.

Hodson was a Methodist and a teetotaller. He had a huge range of interests, including philosophy, genealogy, planning, architecture, music, education and modern art. He was a founder member of his local residents' association and fought inappropriate developments. He was also a keen gardener, winning prizes at his local horticultural society for fruit and vegetables, including greenhouse-grown peaches.

John McMillan

Albert Leslie Hodson, scientist: born Fishlake, South Yorkshire 15 July 1925; married 1958 Joyce Wicks (three sons); died Leeds 1 March 2010.

Have you tried new the Independent Digital Edition apps?
ebookA unique anthology of reporting and analysis of a crucial period of history
Life and Style
Arts and Entertainment
Southern charm: Nicolas Cage and Tye Sheridan in ‘Joe’
filmReview: Actor delivers astonishing performance in low budget drama
Arts and Entertainment
While many films were released, few managed to match the success of James Bond blockbuster 'Skyfall'
Arts and Entertainment
Up my street: The residents of the elegant Moray Place in Edinburgh's Georgian New Town
tvBBC's The Secret History of Our Streets reveals a fascinating window into Britain's past
Albus Dumbledore, the headmaster of Hogwarts School of Witchcraft and Wizardry has been the teaching profession's favourite teacher
Luis Suarez looks towards the crowd during the 2-1 victory over England
Life and Style
Cheesecake frozen yoghurt by Constance and Mathilde Lorenzi
food + drinkThink outside the cool box for this summer’s frozen treats
John Barrowman kisses his male “bride” at a mock Gretna Green during the Commonwealth Games opening ceremony
peopleBarrowman's opening ceremony message to Commonwealth countries where he would be sent to prison for being gay
Sir Bradley Wiggins removes his silver medal after the podium ceremony for the men’s 4,000m team pursuit in Glasgow yesterday
Commonwealth games Disappointment for Sir Bradley in team pursuit final as England are forced to settle for silver
Alistair Brownlee (right) celebrates with his gold medal after winning the men’s triathlon alongside brother Jonny (left), who got silver
England's Jodie Stimpson won the women’s triathlon in the morning
Travel Shop
the manor
Up to 70% off luxury travel
on city breaks Find out more
Up to 70% off luxury travel
on chic beach resorts Find out more
sardina foodie
Up to 70% off luxury travel
on country retreats Find out more
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

SQL Report Analyst (SSRS, CA, SQL 2012)

£30000 - £38500 Per Annum + 25 days holiday, pension, subsidised restaurant: C...

Application Support Analyst (SQL, Incident Management, SLAs)

£34000 - £37000 Per Annum + excellent benefits: Clearwater People Solutions Lt...

Embedded Software / Firmware Engineer

£40000 - £45000 per annum + Pension, Holiday, Flexi-time: Progressive Recruitm...

Developer - WinForms, C#

£280 - £320 per day: Progressive Recruitment: C#, WinForms, Desktop Developmen...

Day In a Page

Backhanders, bribery and abuses of power have soared in China as economy surges

Bribery and abuses of power soar in China

The bribery is fuelled by the surge in China's economy but the rules of corruption are subtle and unspoken, finds Evan Osnos, as he learns the dark arts from a master
Commonwealth Games 2014: Highland terriers stole the show at the opening ceremony

Highland terriers steal the show at opening ceremony

Gillian Orr explores why a dog loved by film stars and presidents is finally having its day
German art world rocked as artists use renowned fat sculpture to distil schnapps

Brewing the fat from artwork angers widow of sculptor

Part of Joseph Beuys' 1982 sculpture 'Fettecke' used to distil schnapps
BBC's The Secret History of Our Streets reveals a fascinating window into Britain's past

BBC takes viewers back down memory lane

The Secret History of Our Streets, which returns with three films looking at Scottish streets, is the inverse of Benefits Street - delivering warmth instead of cynicism
Joe, film review: Nicolas Cage delivers an astonishing performance in low budget drama

Nicolas Cage shines in low-budget drama Joe

Cage plays an ex-con in David Gordon Green's independent drama, which has been adapted from a novel by Larry Brown
How to make your own gourmet ice lollies, granitas, slushy cocktails and frozen yoghurt

Make your own ice lollies and frozen yoghurt

Think outside the cool box for this summer's tempting frozen treats
Ford Fiesta is UK's most popular car of all-time, with sales topping 4.1 million since 1976

Fiesta is UK's most popular car of all-time

Sales have topped 4.1 million since 1976. To celebrate this milestone, four Independent writers recall their Fiestas with pride
10 best reed diffusers

Heaven scent: 10 best reed diffusers

Keep your rooms smelling summery and fresh with one of these subtle but distinctive home fragrances that’ll last you months
Commonwealth Games 2014: Female boxers set to compete for first time

Female boxers set to compete at Commonwealth Games for first time

There’s no favourites and with no headguards anything could happen
Five things we’ve learned so far about Manchester United under Louis van Gaal

Five things we’ve learned so far about United under Van Gaal

It’s impossible to avoid the impression that the Dutch manager is playing to the gallery a little
Screwing your way to the top? Good for Lana Del Rey for helping kill that myth

Screwing your way to the top?

Good for Lana Del Rey for helping kill that myth, says Grace Dent
Will the young Britons fighting in Syria be allowed to return home and resume their lives?

Will Britons fighting in Syria be able to resume their lives?

Tony Blair's Terrorism Act 2006 has made it an offence to take part in military action abroad with a "political, ideological, religious or racial motive"
Beyoncé poses as Rosie the Riveter, the wartime poster girl who became a feminist pin-up

Beyoncé poses as Rosie the Riveter

The wartime poster girl became the ultimate American symbol of female empowerment
The quest to find the perfect pair of earphones: Are custom, 3D printed earbuds the solution?

The quest to find the perfect pair of earphones

Earphones don't fit properly, offer mediocre audio quality and can even be painful. So the quest to design the perfect pair is music to Seth Stevenson's ears
US Army's shooting star: Lt-Col Steven Cole is the man Hollywood calls when it wants to borrow a tank or check a military uniform

Meet the US Army's shooting star

Lt-Col Steven Cole is the man Hollywood calls when it wants to borrow a tank or check a military uniform