... specadd creates a multiple X-ray spectrum FITS file by stacking or putting together (``adding'') two single spectrum files. ... This type of spectral files is particularly useful when the user wants to simultaneously analyse different observations of the same object carried out with the same instrument or with different instruments. ... The Data extension for a multiple spectral dataset stores one single spectrum per row, instead of one channel per row as it is the case of single spectrum files. ...

Instrument Overview . ... Spectral Filters . Quantum Efficiency and Exposure Limits . ... Which Instrument to Use: WFPC2, ACS, NICMOS, or STIS? Comparison of WFPC2 and ACS . Comparison of WFPC2 and NICMOS . Comparison of WFPC2 and STIS . History of WFPC2 . ... WFPC2 . ... What's New in Version 5.0 for Cycle 10 . ... Calibration Channel . ... LRF Photometric Calibration . ... Wood's Filters . ... Sources of Dark Current . ... Calibration Plan Summary . Cycle 4 Calibration Plan . ...

IBIS Data Analysis . ... IBIS . ... Flat Fielding - Introduction . The images obtained by IBIS will have intensity variations across the field of view that are not due to the solar image, but rather caused by instrumental effects that alter the observed intensity in each point of the field of view. ... IBIS Flat Fielding Techniques . ... Therefore, it is desirable to obtain the flat field measurements center on a point along the equator near the heliographic center of the solar disk. ...

... This is possible at modest cost due to the low moments of inertia of the telescope and enclosure. ... This same performance will be achieved in higher winds when the telescope enclosure is facing away from the wind, or by using wind screens. ... The telescope system (MILT) will be remotely operable with an on-site operator's assistance by an astronomer located at one of the ARC member institutions. ... Mean Wind Speed . ... Offsets > 10 deg: 1 arc sec rms max . ... 5 sec max, tracking to tracking . ...

The VLTI Calibrator Selector Tool is a tool intended to assist in the selection of suitable interferometric calibrators for VLTI observations with MIDI and AMBER. It uses a model of the VLTI and its instruments to assess the fringe visibility, given the observed bandpass, the geometry, spectrum, and coordinates of the target and the time at which the observations are to be made. ... The tool offers an HTML/Java based interface and consists of two pages. ... The quality flag depends on LDD_chi2. ...

Next: Echelle Reduction Method Up: No Title Previous: Example . This Chapter provides the basic information necessary to understand the echelle љ package implemented in MIDAS . ... Tutorial examples are available in the system (command TUTORIAL/ECHELLE ) and are also included in the Appendix so that users without previous experience in MIDAS could become familiar with the calibration procedures. ... Reduction steps which are not specific to echelle spectra are described in more detail in Chapter . ...

... Up: Telescope and Instrument Control Systems . ... 216, Astronomical Data Analysis Software and Systems IX, eds. N. Manset, C. Veillet, D. Crabtree (San Francisco: ASP), 271 . ... NASA Goddard Space Flight Center and AppNet, Inc. are developing AIML to command and control astronomical instruments. Our software architecture combines the platform-independent processing capabilities of Java with the power of XML. ... Instrument description is too tightly coupled with details of implementation. ...

... The x-ray spectral analysis consists of a comparison between the observed pulse height spectrum and a pulse height spectrum calculated using a given spectral model. ... To obtain the spectral parameters for an x-ray source, several steps need to be followed. For each source: . ... obtain the best fit parameters for a spectral model - repeated for each model of interest . obtain a 1-D or 2-D grid of values around the best fit values - this can be done for as many models as desired . ...

... Astrophysics Group . ... VSA . ... CAT . ... The Very Small Array is a custom-built radio telescope (operating between 26-36 GHz), designed expressly to make high resolution observations of the cosmic microwave background (CMB) radiation on angular scales around and below one degree. ... The VSA has been operated in ?compact array? and ?extended array? configurations (see the technical description below) and data collected to achieve high sensitivity in both regimes have been analysed. ... 1.75 GHz)...