How I Came into the Field

Ralph Nicholls

[See also related material in the transcript.]

Degree from Imperial College in 1945 when 19.

G.P.Thomson called the 3 people of our class who got firsts together, congratulated us, and said:
a) He needed us to teach. "Nicholls. you will be teaching Geophysics....go and see Bruckshaw"....never had any course on it but there were books-class of 60 vets in October. I also ran the spectroscopy lab, and demonstrated in 2nd year.
b) We should look after our own PhD's.
c) There was room in his accelerator/nuclear group for the best... "But Nicholls you go and see Pearse" (I came 3rd!) The top chap lasted a year. Don Perkins refused electronics and vacuum systems, chose to put nuclear emulsions on the Yungfrauhoch and recorded the first meson -nucleus reaction. Became an FRS. Now Prof Emeritus of Particle Phys. at Oxford.

Pearse (Identification of Molecular Spectra) was very kind, but one was really self supervised. He suggested I look at photoionization continua of negative ions.. not possible at that time in spite of Massey's new little book.

The tribal customs of spectroscopy were (and are) to concentrate on feature wavelengths and to downplay intensities-even though spectra exhibit both. It occurred to me that no one who studied molecular emission spectra had paid attention to excitation conditions and spectral intensities... leading to diagnostics.

So in 1946 (when I had a University of London postgrad fellowship) I built a DC discharge tube (N2+interelectrode langmuir probes + photographic spectra and correlated inter-electrode spectral intensities with electron densities/temperatures, developed the excitation kinetics theory (and FCF's etc). It went very well, using war surplus material. No budgets of course! And no grad courses of course! I gave my Mol. Spec. Grad course for the 40th time this year (Stanford, NASA, UWO and York).

Pearse said: "Nicholls if you spent more time photographing spectra and less time messing around with probes and an oscillograph you would be a lot further ahead!!"

The Gassiot Committee of The Royal Society meeting in July 1947 on "THE EMISSION SPECTRA OF NIGHT SKY AND AURORAE" which I attended reinforced this opinion of little firm knowledge of excitation conditions, and gave my PhD work Auroral relevance. No one at the conference had many ideas about excitation processes.

In 1948 GP said "Nicholls you have been here 3 years, there will not be a job for you next year". Fortunately Dr. Ed Hall, the new President of UWO was at the Commonwealth Universities meetings in Oxford in July 48, and in August was looking for staff....including Physics. A lecturer friend at Imperial College put us in touch, I had an interview and accepted an "instructorship" in Physics (at $2800), and in August was on the Empress of France (first class c/o UWO) en route to Canada. Ed also arranged for DRB to provide me with a microdensitometer, and caused a photographic spectrograph to be found for me at the medical school.

I set up my discharge tube/probe equipment in my UWO office with the spectrograph and microdensitometer. 17 hours a week teaching (also Vets) so there was plenty of time for research!

Transferred from an Internal PhD student to an External PhD student of U.L. status.

In November 1950,1 had made enough progress to start drafting a thesis on "The Kinetics of Excitation of Molecular Nitrogen in Gaseous Electrical Discharges" (I also had two grad students myself by that time), I also gave a short paper with the same title at the Annual Meeting of OSA in Cleveland. It was the last paper on a wet Saturday aftemoon...4 people (all from AFCRL) left in the audience. They were very kind and on Monday Nate Gerson, called me and after some discussion offered me a $67K/yr contract for lab work and theory on diagnostic spectroscopy related to auroral excitation mechanisms (see his PiC paper about support at U Sask. UWO, U of T and McGill).

We launched the contract in 1951 with an International Conference on Auroral Physics in July. I had told him of the Gassiot Committee meeting and many of the same people took part.

Also my two University of London external PhD examiners (Pearse and Bates) and I held my PhD oral in my office on the day I gave my paper!!! (Many years later, as Chairman of the York Hon. degs. committee I was able to arrange for D.Sc.'s for Bates (and later Massey) (and also later for Balfour Cume and Frank Davies together).

And the rest as they say is history. Our work at UWO (spread around in the department) went very well, lots of excellent grad students and PDF's (Don McEwen, Bill Parkinson. Ed Reeves, Peter Fraser etc etc etc).

Moved to York to set up Physics and CRESS in 1965 with a very multi-disciplinary flavour.

Current NSERC Grant: SPACE SPECTROSCOPY: HiRES, Photodissociation and Molecular Reference Data