Optical and UV Spectrophotometric Standard Stars . ... Apache Point expresses its thanks to J. R. Walsh and to ESO for allowing us to place a copy of these pages at Apache Point. ... Access to the standards is either through: . ... The data for the standard stars come from four sources: . ... Data for 23 stars based on IUE and optical spectra and calibrated by the primary WD standards. ... The data from which the plots were produced are also available by ftp access from the standard star pages. ...

... Stellar Evolution is driven entirely by the never ending battle between Pressure and Gravity . As imbalances are reached, the star is driven to find a new Energy source. ... Pressure and gravitational forces are equal, the star is stable and its core is sufficiently hot to fuse Hydrogen into Helium More about main sequence stars . ... The luminosity generated by the core fusion of Helium into Carbon is far greater than the shell luminosity associated with the fusion of Hydrogen into Helium. ...

... 77, 1995 R. A. Shaw, H. E. Payne, and J. J. E. Hayes, eds. Restoration of HST WFPC2 Images in Gyro­Hold Mode J. Mo and R. J. Hanisch Space Telescope Science Institute 1 , 3700 San Martin Drive, Baltimore, MD 21218 Abstract. ... Image restoration techniques developed for use on aberrated HST images have been adapted for use to remove this motion blur. Experiments have been done on WFPC 2 images of NGC 330 and NGC 422 (having exposure times of 80 and 100 s in gyro­ hold mode) with complete success. ...

... Recalibration / 26-10 . ... DPERSC-CP34SE: ...and 0 packets were found to have segments without Reed Solomon corrections CPEEND- DATA EDITING ENDED 31-AUG-94 16:23:20 FOR U28S0303P . CPE0EN--------------------------------------------- DATA EDITING COMPLETED ----------------------------------------------------- CPG0VS--------------------------------------------- DATA EVALUATION STARTED ----------------------------------------------- DPVSTR- DATA EVALUATION STARTED 31-AUG-94 16:23:39 FOR ...

Next: Reduction procedure Up: Extinction and transformation Previous: Strategy . Standard stars can be included in the extinction solution, if one is careful. The problem is that there are usually appreciable ``conformity errors'' due to mismatch between the instrumental and the standard passbands [ 16 ]. ... Thus, it is wrong to assume that the transformation between the instrumental system and the standard system is exact, even if there were no measurement error in either system [ 1 ]. ...

... This routine is designed to read in the current correlator set-up, go to the chosen source, and then take data pointing directly at the specified source. This routine will automatically wait until you are on source before beginning to take data. ... Additionally, this routine allows you to take an ON/OFF calibration pair (one 10s scan with the noise diode on, followed by a 10s scan with the diode off), using the chosen noise diode configuration (see Section 1.6 . ...

... NONE causes the system to do only the same background monitoring that is done when the antenna is idle. SPECIAL or a specific file name uses a special list of monitor points and logging intervals provided by the VLBA operators. ... STANDARD , NONE , and POINTING are not case sensitive. Any special file name must match in case the name of the file loaded at the sites. ... Options: STANDARD , NONE , POINTING , or the name of a special logging file that the operators have put at the stations. ...