rvsao. bcvcorr Parameters

  • Spectra spectra specnum specdir specsky subgrav
  • Sky Direction keyra keydec keyeqnx ra dec equinox
  • Timing keyhjd keyjd keydate keystart keymid keyend keyexp hjd gjd year month day ut
  • Observatory obsname keyobs keylat keylong keyalt obslong obslat obsalt
  • Results savebcv savejd bcv hcv verbose printmode debug

    Spectra [contents] [index]

    spectra ""
    List of input spectra
    specnum "0"
    Spectrum number(s) if multispec file
    specdir ""
    Directory for input spectra
    specsky no
    Is spectrum twilight sky? (yes or no) If yes, earth-sun direction is used to compute the velocity corrections. The BCV and HCV will be close but not identical because the direction to the center of the sun's light is not the same as the direction to the solar system barycenter.
    subgrav no
    Subtract solar gravitational redshift from twilight sky (yes or no) If subgrav=yes and specsky=yes, subtract a correction for the sun's gravity (0.636) from the barycentric and heliocentric corrections computed by the program. If savebcv=yes, BCV, HCV, and SGRV are written to the image header. HCV, the velocity of the sun relative to the spectrograph with the gravitational correction subtracted, should be used as the spectrum correction
    when cross-correlating twilight spectra with XCSAO.

    Sky direction [contents] [index]

    keyra "RA"
    Right ascension header keyword
    keydec "DEC"
    Declination header keyword
    keyeqnx "EPOCH"
    Coordinate equinox header keyword
    ra INDEF
    Right ascension of observation. If not INDEF, it is expected to be in the format hh:mm:ss.sss or decimal hours.
    dec INDEF
    Declination of observation. If not INDEF, it is expected to be in the format dd:mm:ss.sss or decimal degrees.
    equinox 1950.0
    Epoch of equinox (usually 1950.0 or 2000.0) of coordinates.

    Timing [contents] [index]

    keyhjd "HJD"
    Header keyword for Heliocentric Julian date at midtime of observation. This date is used for logging purposes, NOT for computation of the barycentric velocity correction.
    keyjd "JD"
    Header keyword for Geocentric Julian date at middle of observation. If this parameter is present, no other time is needed.
    keydate "DATE-OBS"
    Header keyword for date of observation (dd/mm/yyyy)
    keystart "UTOPEN"
    Header keyword for UT at start of observation
    keymid "UTMID"
    Header keyword for UT in middle of observation
    keyend "UT"
    Header keyword for UT at end of observation
    keyexp "EXPOSURE"
    Header keyword for duration of observation in seconds. If keymid is not present, half the exposure duration is added to keystart or subtracted from keyend.
    hjd 0.0
    Heliocentric Julian Date of observation (only used if > 0)
    gjd 0.0
    Julian Date of observation (only used if > 0)
    year INDEF
    UT year of observation (only used if not INDEF)
    month INDEF
    UT month of observation (only used if not INDEF)
    day INDEF
    UT day of month of observation (only used if not INDEF)
    ut INDEF
    Universal Time of observation (only used if not INDEF)

    Observatory Location [contents] [index]

    obsname "file"
    Observatory name. If "file", read from image header using the following keywords. Otherwise, look it up in IRAF's observatory database. If the string is not found there, use the position given by the parameters below.
    keyobs "SITENAME"
    Observatory name header keyword
    keylat "SITELAT"
    Observatory latitude header keyword
    keylong "SITELONG"
    Observatory longitude header keyword
    keyalt "SITEALT"
    Observatory altitude header keyword
    obslong 0.0
    Observatory longitude, used if obsname is not found.
    obslat 0.0
    Observatory latitude, used if obsname is not found.
    obsalt 0.0
    Observatory altitude in meters, used if obsname is not found.

    Results [contents] [index]

    savebcv no
    Save computed BCV and HCV in data file header (yes or no)
    savejd no
    Save computed GJD (as GJDN), HJD (as HJDN), and midtime (as UTMID) in data file header (yes or no)
    Computed barycentric velocity (returned)
    Computed heliocentric velocity (returned)
    verbose yes
    Displays heliocentric and barycentric corrections
    printmode 1
    1=Display heliocentric and barycentric corrections and ancillary data
    2=Display only BCV
    debug no
    Displays intermediate results

    BCVCORR Parameters, Alphabetically

    bcv day debug dec equinox gjd hcv hjd keyalt keydate keydec keyend keyeqnx keyexp keyhjd keyjd keylat keylong keymid keyobs keyra keystart month obsalt obslat obslong obsname printmode> ra savebcv savejd specsky specdir specnum specsky spectra subgrav ut verbose year

    [rvsao] [bcvcorr]

    Last updated 13 March 2012