Indian Astrophysicist

(1893- 1956)

Born October 6 1893 Dhaka BangaladeshResidence India

Nationality Indian

Fields Physics and Mathematics

Institution Allahabad University

university of Calcutta

Imperial college London

Indian Association for cultivation of Science

Almamater Dhaka College

University of Calcutta

Known For Thermal Ionization

Saha Ionization Equation

Spouse Radha Rani Saha

Died February 16 1956 Delhi

IN A NUTSHELL………………….

Meghnad Saha's best-known work concerned the thermal

ionisation of elements, and it

led him to formulate what is known as the Saha equation.

This equation

is one of the basic tools for

interpretation of the spectra of

stars in astrophysics. By

studying the spectra of various

stars, one can find their

temperature and

from that, using Saha's

equation, determine the

ionisation state of the various

elements making up the star.

scientific institution formed by M N Saha

Physics Department In Allahabad University

Institute Of Nuclear Physics In Calcutta

National Academy Of Science (1930)

The Indian Physical Society (1934)

Indian Institute Of Science (1935)

Indian Association For The Cultivation Of Science (1944)

SAHA INSTITUTE OF NUCLEAR PHYSICS

SAHA INSTITUTE OF NUCLEAR PHYSICS

Receiving M N Saha award from Dr. Murali ManoharJoshi (Minister of HRD)

PRESIDENCY COLLEGE KOLKATTA

MEGHNAD SAHA was a great Indian scientist.

He made remarkable contribution to the field of Astrophysics. He put forward an “ionization formula” which explained the presence of the spectral lines He was born in Seoratali, Dacca district, now in Bangladesh, on October 6, 1893. He was the fifth child of his parents, Sri Jagannath Saha and Smt. Bhubneshwari Devi.Meghnad Saha took admission in the Kishorilal Jubilee School and passed the Entrance examination of the Calcutta University in 1909, standing first among the student from East Bengal obtaining the highest marks in languages (English, Bengali and Sanskrit combined) and in Mathematics. . He was only taught by eminent teachers like J. C. Bose and P. C. Ray but had brilliant contemporaries like S. N. Bose and P. C. Mahalanobis, who, like him, became noted scientists in due course.

.

POINTS ABOUT SAHA………………….

In 1913, he graduated from Presidency College with Mathematics major and got the second rank in the first one. In 1915, Meghnad Saharanked first in M.Sc. Applied Mathematics exam, . In 1927, Meghnad Saha was elected as a fellow of ‘London’s Royal Society’. He invented an instrument to measure the weight and pressure of solar rays. He produced the famous equation, which he called ‘equation of the reaction-isobar for ionization’, which later became known as Saha’s“Thermo-Ionization Equation”. In 1952 he stood as an independent candidate for Parliament and was elected by a wide margin. He not only tried to raise the status of science in independent India, but also served the cause of the poor He was the chief architect of river planning in India. He prepared the original plan for Damodar Valley Project. Meghnad Saha was an Indian astrophysicist who nominated for the ‘Nobel prize’ in physics in 1935-36. He died on february 16, 1956 due to a heart attack.

•The Principles of Relativity (with S.N. Bose) Calcutta

University, Calcutta, 1920. (It was a translation of

Einstein’s papers on theory of relativity).

•Treatise on Heat (with B.N. Srivastava), Indian Press,

Allahabad, 1931.

•Junior Text-Book on Heat (with B.N. Srivastava),

Indian Press, Allahabad, 1932.

•Treatise on Modern Physics, Vol-1 (with N.K. Saha)

Indian Press, Allahabad, 1934.

•My Experience in Soviet Russia, Bookman Inc,

Calcutta, 1947.

BOOKS WRITTEN BY M N SAHA

SAHA IONIZATION EQUATION

For a gas composed of simple atomic species, the Saha equation is written as

.

Where ni is the density of atom in the i- th state of ionizationgi is the degeneracy of states for the i-ions£i is the energy required to remove i-electrons from a neutral atomne is the electron density

is the thermal De Brogli wavelength of an electron

me is the mass of electron T is the temperatureKB is the Boltzman constanth is Planck’s constant