A comparison between the results of applying a ring diagram analysis to two data sets is described in order to check the quality of the two sets and the reliability of the method. The series used have been obtained with two different helioseismological instruments with the same spatial resolution. A section of 30 × 30 deg2 about the disk center has

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Twelve magnetic Chemically Peculiar (CP2) stars of the SiSrCrEu subgroup mostly brighter than the 7.5 visual magnitude have been investigated in the infrared at 1.25, 1.6 and 2.2 mu . The stars HD 74521, HD 90044, HD 119419, HD 125630, and HD 187473 are clearly variable in the near infrared with the same period as the visible light, spectrum, and

Rotation curves and velocity dispersion profiles are presented for both the stellar and gaseous components along five different position angles (PA =5(deg) , 50(deg) , 95(deg) , 125(deg) , and 155(deg) ) of the nearby barred spiral NGC 6221. The observed kinematics extends out to about 80'' from the nucleus. Narrow and broad-band imaging is also

The support costs of a system during the operational phase of its life-cycle represent a substantial part of the total life-cycle cost. Also, the support costs strongly depend on the decisions taken during the initial stages of the system design. However, traditionally many major systems have been developed attending only to the criteria deriving

INTEGRAL is an optical fiber unit for performing 2D spectroscopy of extended objects at the 4.2 m. William Herschel Telescope (WHT). It is mounted at the GHRIL Nasmyth focus together with newly built acquisition, guiding, and calibration units. It makes use of the specially designed fiber spectrograph WYFFOS. This system allows up to six bundles to