It's not something I have ever heard, so it's very unlikely there is an abbreviation. Even the name seems a little odd. A candidate for what? e.g. a Candidate for PhD in Historical Sciences, a Candidate for the vacant position in Historical Sciences.

I have never heard of "Historical Sciences." Do you mean the "history of science?" For example, how Pavlov's work on conditioned reflexes influenced American behaviorism? And what is a "Candidate?" I've heard this before when people are speaking about higher education outside the US but I don't know what it means. In the United States, at a doctoral level, there are a handful of degrees in specific professional fields that have specific names. Examples include doctors of law (JD), dentistry (DDS), medicine (MD), optometry (OD). Most of them, however, are just PhD degrees "in" something. You can receive a PhD in education, a PhD in zoology, and a "PhD in the history of science." See, for example: https://gsas.harvard.edu/programs-of-study/all/history-science "The Department of the History of Science offers a comprehensive graduate program leading to the AM and PhD degrees."

Я занимаюсь переводом научных статей, и в журналах, с которыми я работаю, принято сокращение вида Cand. Sci. (History) или Cand. Sc. (History). Однако, на Западе, за пределами сугубо академической сферы, звание кандидата наук не очень известно и понятно, так что, возможно, его не стоит сокращать вовсе.

Hi, Sasha. I agree with Gary that it's better not to be abbreviated. I found sentences like this: Postgraduate education leads to the Kandidat Nauk (Candidate of Sciences) and the Doctor of Sciences. I think it's a good way to express your intention in English: both the original and the explanation are offered. Probably Candidate Doctor is foeign to westerners. But there are some people who have studied in Russia and Ukrain and abtained it ( called in Chinese as fù bóshì, assistant doctor ). Can you please tell me if it's a formal degree or it's non-degree but an educational attainment?

One thing you should know is that in the US, education is not standardized. If John has a degree, you don't really know what work he did for the degree - you just know that some school was willing to give John a degree. A Doctorate at some schools is 2 years, some is 5 years, some takes closer to 7 - and each department at each schools might have different standards. It probably requires a thesis (but not always). It might require tests (but not always). It might require publishing (but, again, not always). Also, schools can grant whatever degrees they want (it would shock me there wasn't a school somewhere that offered a "Historical Sciences" degree - but who knows what they mean by historical sciences) So if you're a Candidate in Human Sciences, say that - I agree that you should use cyrillic. And if someone asks what it is, make sure you're clear it's a post graduate degree (based on the description, it sounds vaguely like an interdisciplinary Masters in social sciences or almost an ABD)