The proton flare of August 28, 1966

The proton flare of August 28, 1966 began on H α records at 15 h 21 m 35 s UT. It presented an unusually complex development with flare emission occurring in two distinct plages. The brightest part of the flare attained maximum intensity, 152 % of the continuum, between 15 h 30 m and 15 h 32 m UT. Photometric measurements show that a long-enduring part of the flare continued to decline in intensity until at least 21 h 20 m UT.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43737/1/11207_2004_Article_BF00148084.pd

Some comments on flares after many years of observation

Ground based observations of flares are reviewed to seek implications for a flare build-up on either a long or a short time scale. Plots of flare frequency and importance for certain individual centers of activity suggest a possible crescendo in flare occurrence days and hours before the development of large and significant flares. The X-ray records follow the same pattern of apparent build-up. A possible dependence between successive major flares, as phases one and two of a single complex flare event, suggests that the time scale in which the total flare event takes place may show extreme variation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43743/1/11207_2004_Article_BF00152264.pd

Major Hα flares in centers of activity with very small or no spots

Major Hα flares (importance ⪖ 2) in plages with only small or no spots constitute a rare but well observed aspect of solar activity. Information relating to 83 such flares has been assembled and studied. In the years 1956–1968 these flares represented ∼ 7% of all confirmed flares of importance ⪖ 2. In general, the flares were of unusually long duration and rose to maximum intensity slowly. A flash phase was often absent or poorly defined. In a number of cases, the flare emission included two bright filaments more or less parallel. The flares usually occurred during the late, flare-poor phase of a center of activity, and their outbreak did not presage a resurgence of activity in subsequent rotations. The flares were frequently associated with the position of dark filaments.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43710/1/11207_2004_Article_BF00153560.pd

Problems of differentiation of flares with respect to geophysical effects

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32125/1/0000178.pd

Basic solar research : the solar chromosphere and high energy radiation : final report : for the period July 1, 1956-September 30, 1970

http://deepblue.lib.umich.edu/bitstream/2027.42/6662/5/bac9218.0001.001.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/6662/4/bac9218.0001.001.tx

UMRI projects 2451-1 and 2451-2 : quarterly reports

http://deepblue.lib.umich.edu/bitstream/2027.42/3276/5/bab2729.0001.001.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/3276/4/bab2729.0001.001.tx

UMRI projects 2451-1 and 2451-2 reports, 1958-1959

http://deepblue.lib.umich.edu/bitstream/2027.42/4617/5/bad1307.0001.001.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/4617/4/bad1307.0001.001.tx

ORA projects 03941 [Studies of variations in the earth's magnetic field due to solar activity] and 03942 [Jet task] : quarterly reports

http://deepblue.lib.umich.edu/bitstream/2027.42/3273/5/aas0820.0001.001.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/3273/4/aas0820.0001.001.tx

ORA projects 03941 and 03942 : final reports

http://deepblue.lib.umich.edu/bitstream/2027.42/3274/5/bab2741.0001.001.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/3274/4/bab2741.0001.001.tx