Linear sensitivity of helioseismic travel times to local flows
نویسندگان
چکیده
منابع مشابه
The Linear Sensitivity of Helioseismic Ring Diagrams to Local Flows
Ring-diagram analysis is a technique of local helioseismology used to infer plasma flows in the solar convection zone which generates intermediate data products known as ring-fitting parameters. Knowing the sensitivity of ringfitting parameters to actual flows in the Sun is important for interpreting these measurements.Working in plane-parallel geometry, we compute the linear sensitivity of rin...
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We study the sensitivity of wave travel times to steady and spatially homogeneous horizontal flows added to a realistic simulation of the solar convection performed by Robert F. Stein, Ake Nordlund, Dali Georgobiani, and David Benson. Three commonly used definitions of travel times are compared. We show that the relationship between travel-time difference and flow amplitude exhibits a non-linea...
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Consider the random walk among N places with N(N - 1)/2 transports. We attach an exponential random variable Xij to each transport between places Pi and Pj and take these random variables mutually independent. If transports are possible or impossible independently with probability p and 1-p, respectively, then we give a lower bound for the distribution function of the smallest path at point log...
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BACKGROUND An increasing number of studies use GIS estimates of car travel times to health services, without presenting any evidence that the estimates are representative of real travel times. This investigation compared GIS estimates of travel times with the actual times reported by a sample of 475 cancer patients who had travelled by car to attend clinics at eight hospitals in the North of En...
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ژورنال
عنوان ژورنال: Astronomische Nachrichten
سال: 2007
ISSN: 0004-6337,1521-3994
DOI: 10.1002/asna.200610724