view Abstract Citations (34) References (22) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Physical conditions in granulation. Altrock, R. C. ; Musman, S. Abstract High-resolution spectroheliograms made in the Ti I and Fe I 5016-A lines with the diode array of a tower telescope are analyzed. Temperature perturbations (delta T) were introduced into the Harvard-Smithsonian Reference Atmosphere and varied empirically until the calculated line profiles matched the observed profiles. It is found that the absolute value of delta T increases going downward in the low photosphere. In the middle photosphere, the absolute value does not exceed 70 K. It is also found that the large buoyant forces implied by the solutions for delta T are inconsistent with the small observed accelerations in the granular flow. It is concluded that this incompatibility provides additional evidence besides line broadening for the existence of microturbulence in the low photosphere. The convective flux at an optical thickness of 3 (5000 A) is small compared with the total flux. Also, the temperature fluctuations are much larger than those that would be produced by the observed convective velocities alone. Thus, the observable low photosphere appears to be near radiative equilibrium. Publication: The Astrophysical Journal Pub Date: January 1976 DOI: 10.1086/154109 Bibcode: 1976ApJ...203..533A Keywords: Atmospheric Temperature; Solar Atmosphere; Solar Temperature; Spectroheliographs; Spectrum Analysis; Atmospheric Models; Atmospheric Turbulence; Continuous Spectra; Convective Flow; Data Reduction; Electron Pressure; Heat Flux; Photosphere; Temperature Gradients; Velocity Distribution; Solar Physics full text sources ADS |