http://hdl.handle.net/2248/1705 Tue, 14 Apr 2026 09:55:54 GMT 2026-04-14T09:55:54Z https://prints:443/jspui/retrieve/de6808a7-976f-426f-a0ee-0fa3b2e11b40/das.jpg http://hdl.handle.net/2248/1705 http://hdl.handle.net/2248/6631 Title: Progress of meteorology in India Authors: Das, A. K Description: Open Access Sat, 01 Jan 1938 00:00:00 GMT http://hdl.handle.net/2248/6631 1938-01-01T00:00:00Z http://hdl.handle.net/2248/4530 Title: Distribution of radiation flux across a sunspot Authors: Das, A. K; Ramanathan, A. S Description: Open Access Thu, 01 Jan 1953 00:00:00 GMT http://hdl.handle.net/2248/4530 1953-01-01T00:00:00Z http://hdl.handle.net/2248/4529 Title: Temperature at the poles and at the equator of the sun Authors: Das, A. K; Abhyankar, K. D Abstract: The equivalent widths of the g and K lines are measured at the pole and at the equator of the Sun during a period of minimum solar activity. The difference of temperature between pole and equator is evaluated by Woolley's method of the calcium ionization temperature. The pole is found to be hotter than the equator by 96° ± 18° or 86° ± 16°, depending upon the choice of the values of the continuous absorption coefficients. This result lends support to Bjerknes's thermohydrodynamical theory of sunspots. Using Bjerknes's theory, the depth of the sunspot umbral column is calculated from the observed difference of temperature between pole and equator and is found to be 125 km or 140 km. Description: Restricted Access Sat, 01 Jan 1955 00:00:00 GMT http://hdl.handle.net/2248/4529 1955-01-01T00:00:00Z http://hdl.handle.net/2248/4518 Title: Kodaikanal Observatory Authors: Das, A. K Description: Restricted Access Sat, 12 Jul 1952 00:00:00 GMT http://hdl.handle.net/2248/4518 1952-07-12T00:00:00Z