Engineering Papers⌕ Search

Engineering topics

Kundu, M. R.

Publications and source records attributed to Kundu, M. R..

188 records · Page 11
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

Observations of prominences at 3.5 millimeter wavelength.

At 3.5 mm wavelength, absorption features are observed in correspondence with H-alpha dark filaments on the disk; beyond the limb, the prominences correspond to emissive regions. The absorption features are larger than the corresponding H-alpha dark filaments; the emissive regions at the limb have similar angular sizes. The emissive regions at the limb have electron temperatures of 5500 (plus or minus 500) K; the amount of absorption observed on the disk leads to mean electron densities of about 50 billion per cu cm.

Kundu, M. R.↗
NASA NTRS1972

Polarization of solar active regions at 9.5 mm wavelength.

A study of the circular polarization structure of solar active regions has been made from data obtained at 9.5 mm. All important active regions observed at 9.5 mm are bipolar in nature, the degree of polarization is about the same for both right and left circular components, and it ranges up to about 4%. These oppositely polarized components correspond with the Mt. Wilson magnetic regions of opposite polarity; the line of zero polarization delineates clearly the neutral line between the regions of opposite polarity on magnetograms. Unipolar regions in magnetograms also show up as unipolar regions at 9.5 mm. Magnetic fields as low as 5-10 G on magnetograms manifest as distinctly polarized regions on 9.5 mm maps.

Kundu, M. R.↗
NASA NTRS1971

Solar radio emission at 1.2 mm wavelength.

A 36-ft radio telescope was used in the investigations. The 1.2 mm wavelength receiver connected to the telescope is a helium-cooled germanium bolometer. The 1.2 mm solar maps were obtained by scanning the sun in right ascension at the rate of 1 deg per minute. A temperature of 6000 K was assumed for the 1.2 mm quiet sun temperature for all solar maps. Eight maps at 1.2 mm were obtained on six different days. The 1.2 mm regions are rather large and without much structure; they are closely associated with Ca-plage regions.

Kundu, M. R.↗
NASA NTRS1970

Solar active regions at millimeter wavelengths

Solar active regions at millimeter wavelengths, discussing brightness temperature, background radiation, electron density, optical thickness, polarization and chromospheric magnetic fields

Kundu, M. R.↗