7,031 research outputs found
Annual and solar-magnetic-cycle variations in the interplanetary magnetic field, 1926-1971
The analysis of forty-five years of inferred interplanetary magnetic field polarity shows an annual variation and a variation of about twenty years, associated here with the solar magnetic cycle. On the average the phase of the annual variation of the interplanetary field changes about 2 and 2/3 years after sunspot maximum, i.e. for about ten consecutive years the predominant polarity of the interplanetary field is away from the sun during the six-month interval in which the earth is at southern heliographic latitudes. Then a change of phase occurs so that for about the next ten years the predominant polarity is toward the sun, while the earth is at southern heliographic latitudes. The annual variation changes its predominant polarity within a few days of the times when the heliographic latitude of the earth is zero
Single Event Effect Testing of the Texas Instruments' MAX4595 Single-Channel Analog Switch
The Texas Instruments' (TI) MAX4595 was tested for single event latch-up (SEL) response at the Texas A&M University Cyclotron Facility (TAMU) on 26 October 2014. The device was exercised in varied load conditions to replicate its intended application with concerns about destructive effects on the commercial device
Response of the geomagnetic activity index Kp to the interplanetary magnetic field
Response of geomagnetic activity index to interplanetary magnetic fiel
The equatorial rotation velocity of the photosphere is measured to be the same as sunspots
The equatorial rotation rate of the photosphere was measured at effect data. It was found that scattered light has a large influence and must be taken into account properly. When this was done it was found that the rotation rate from Doppler shifts agreed very well with the rate found for sunspots. Short-term fluctuations in rotation rate (i.e. from day to day) were less than plus or minus 15 m/s and were thus within observational errors
A physical mechanism for the prediction of the sunspot number during solar cycle 21
On physical grounds it is suggested that the sun's polar field strength near a solar minimum is closely related to the following cycle's solar activity. Four methods of estimating the sun's polar magnetic field strength near solar minimum are employed to provide an estimate of cycle 21's yearly mean sunspot number at solar maximum of 140 plus or minus 20. This estimate is considered to be a first order attempt to predict the cycle's activity using one parameter of physical importance
The origin of the warped heliospheric current sheet
The warped heliospheric current sheet in early 1976 was calculated from the observed photospheric magnetic field using a potential field method. Comparisons with measurements of the interplanetary magnetic field polarity in early 1976 obtained at several locations in the heliosphere at Helios 1, Helios 2, Pioneer 11 and Earth show a rather detailed agreement between the computed current sheet and the observations. It appears that the large scale structure of the warped heliospheric current sheet is determined by the structure of the photospheric magnetic field, and that "ballerina skirt" effects may add small scale ripples
A model of interplanetary and coronal magnetic fields
Model of interplanetary and solar magnetic field structure above photosphere using Green function solution to Maxwell equation
The sun's magnetic sector structure
The synoptic appearance of solar magnetic sectors is studied using 454 sector boundaries observed at earth during 1959-1973. The sectors are clearly visible in the photospheric magnetic field. Sector boundaries can be clearly identified as north-south running demarcation lines between regions of persistent magnetic polarity imbalances. These regions extend up to about 35 deg of latitude on both sides of the equator. They generally do not extend into the polar caps. The polar cap boundary can be identified as an east-west demarcation line marking the poleward limit of the sectors. The typical flux imbalance for a magnetic sector is about 4 x 10 to the 21st power Maxwells
Comparison of the mean photospheric magnetic field and the interplanetary magnetic field
Polarity comparison of solar magnetic field and interplanetary magnetic fiel
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