The magnetic fields of active regions

✍ Robert F. Howard 📂 Article 📅 1991 🏛 Springer 🌐 English ⚖ 720 KB

Magnetogram data are analyzed to study daily variations of tilt angles of the magnetic axes of active regions defined by magnetic fields measured with the Mount Wilson magnetograph. The period covered by this daily data set is 1967 through April 9, 1990. It is found that on average regions with posi

✍ Robert F. Howard 📂 Article 📅 1989 🏛 Springer 🌐 English ⚖ 826 KB

The Mount Wilson daily magnetogram data set is used in its coarse format to determine various statistical properties of magnetic regions. The method of defining magnetic regions is described, and also the criteria for a 'return' of a magnetic region from one day to the next are given. Region sizes,

The magnetic fields of active regions

✍ Robert F. Howard 📂 Article 📅 1991 🏛 Springer 🌐 English ⚖ 469 KB

The magnetic fields of active regions

✍ Robert F. Howard 📂 Article 📅 1990 🏛 Springer 🌐 English ⚖ 538 KB

The Mount Wilson coarse array data set is used to define active regions in the interval 1967 to August, 1988. From the positions of these active regions on consecutive days, rotation rates are derived. The differential rotation of the active regions is calculated and compared with previous magnetic

The magnetic fields of active regions

✍ Robert F. Howard 📂 Article 📅 1991 🏛 Springer 🌐 English ⚖ 673 KB

The magnetic fields of active regions

✍ Robert F. Howard 📂 Article 📅 1991 🏛 Springer 🌐 English ⚖ 663 KB

The Mount Wilson coarse array magnetograph data set is analyzed to determine characteristics of magnetic regions as a function of distance from the average latitude, ~o, of regions in each hemisphere, a quantity which varies during the activity cycle. Regions with normal polarity axis orientations a