This document describes the list of controlled terms used to build the
Unified Content Descriptors, Version 1+ (UCD1+).
The document describing the current proposal for a new set of UCD called UCD1+
can be found at the url: http://www.ivoa.net/Documents/latest/UCD.html.
Here we briefly recall the structure of the proposed UCD1+ and the origin of
the present lists.
Status of this document
This is an IVOA Proposed Recommendation made available for public review.
It is appropriate to reference this document only as a recommended
standard that is under review and which may be changed before it is
accepted as a full recommendation.
Comments on this document can be posted on the dedicated RFC page at
http://www.ivoa.net/twiki/bin/view/IVOA/UCDListRFC
General discussion on UCD can be sent to ucdi voa.net, a mailing list with a public archive.
This document is based on the W3C documentation standards, but has been
adapted for the IVOA.
1 Definition of atoms and words
A UCD is a string which contains textual tokens called ``words'', separated
by semicolons(;). A word is composed of ``atoms'', separated by periods(.).
So the hierarchy is the following:
atoms --> words --> composed words
UCD1+ are either single words, or a composition of several words.
UCDs should be "controlled" (through a process that is also indicated in the
reference document above). Control should be exercised at the level of words (ucd1+)
but also at the level of the vocabulary (atoms) used to form words.
A consistent list of atoms should be mantained, making sure that the same
atom means always the same thing, even if used in combination with different
other atoms.
1.1 Definition of atoms
Atoms were defined following these guidelines:
1. abbreviations are kept to a minimum, and only if the result is not
ambiguous (ra, dec are OK, but t is ambiguous: we use time and
temperature instead).
2. atoms are not hyphenated. The separation is
marked by a capital letter to help readability (position angle = posAng)
unless the composed word has a well known acronym (signal to noise ratio = snr)
or short form (standard deviation = stdev)
1.2 Definition of words
The list of UCD1+ words presented in this document was initially generated applying
the rules and recommendations of PR-UCD-20040823 to catalogues/tables in VizieR.
The original motivation was to transform old UCD1 into an improved version,
trying to build a list of combinations of new words that could describe
all the existing UCD1 terms.
The list of UCD1+ words is maintained by the UCD Scientific Board, following
the procedure defined in the UCD Recommendation document
(http://www.ivoa.net/Documents/latest/UCD.html).
A few words in the present list do not strictly comply with one of the recommendations
(for any two words at the same level in the hierarchy, one can't be a
starting substring of the other), mostly for readibility reasons.
2 The structure of the UCD1+ tree
All existing UCD1+ words are grouped into 12 main categories. These
categories are expressed by the first atom of the word, whose possible
values are:
arith (arithmetics)
We include in this section concepts involving or indicating some
mathematical operation performed on the primary ``concept'' or just
the presence of an arithmetic factor or operator.
em (electromagnetic spectrum)
This section describes the electromagnetic spectrum, either in a
monochromatic way or in predefined intervals. The complete list of
proposed bands (in seven classical regions of the e.m. spectrum: radio,
millimeter, infrared, optical, ultraviolet, x-ray and gamma-ray), can
be found in the document
Note-EMSpectrum-20040520
instr (instrument)
In this section we gather all the quantities related to astronomical
instrumentation, e.g. detectors (plates, CCDs, etc.), spectrographs,
telescopes (but also observatories or missions), etc.
meta (metadata)
This section includes all the information that is not coming directly
from a measure, and info that could not be included in other sections.
obs (observation)
In principle under this section should go all words describing an
observation (the name of the observer or PI, the observing conditions,
the name of the field). In practice, the section is very ``thin''
and could be deleted, if the sparse content could be housed elsewere.
phot (photometry)
All the words describing photometric measures are included in this section.
Basically we distinguish between a flux density (flux per unit frequency
interval), a flux density integrated over a given e.m. interval (flux
if expressed linearly, mag if expressed by a log), or a flux expressed in
counts/s (if the setup of the detector is photon counting observing mode).
We also include ``colors'', which are differences of magnitudes (i.e.
ratios of fluxes) measured in different e.m. bands.
In the present proposal we tried to simplify the PHOT section of old
UCD1, keeping only the most important (used, diffuse) colors.
phys (physics)
Atomic and molecular data (mainly used for spectroscopy) and basic
physical quantities (temperature, mass, gravity, luminosity, etc.)
pos (positional data)
All quantities related to the position of an object, in general on the sky.
Angular quantities, with the exception of projections from spherical to
rectangular systems.
Also angular measurements in general (the angular size of an object is
in this section, its linear size is in the phys section).
The WCS FITS keywords are placed here for the moment.
spect (spectral data)
For historical reasons, photometric data taken in narrow spectral bands
with instruments called spectrographs are classified as spectroscopic
data.
Don't miss up with ``em''. Bi-dimensionally speaking, em represents the x
axis, phot and spect the y axis.
src (source)
This is a rather generic section, mainly devoted to source classifications.
For no other than practical reasons, variability, orbital and velocity data
are also included in this section.
stat (statistics)
Statistical information on measurements.
time (time)
Quantities related to time (age, date, period, etc.)
A List of valid words
All words are preceded by a ``syntax'' code that can help in the process
of building composed UCD1+.
The code "P" means that the word can only be used as "primary" or first word;
"S" stands for only secondary: it can't be used as the first word to describe
a single quantity;
"Q" means that the word can be used indifferently as first or secondary word;
"E" means a photometric quantity, and can be followed by a word describing
a part of the electromagnetic spectrum
"C" is a colour index, and can be followed
by two successive word describing a part of the electromagnetic spectrum;
"V" stands for vector. Such a word can be followed by another describing the
axis or reference frame in which the measurement is done
Q | arith | Arithmetic quantities
S | arith.diff | Difference between two quantities described by the same UCD
P | arith.factor | Numerical factor
P | arith.grad | Gradient
P | arith.rate | Rate (per time unit)
S | arith.ratio | Ratio between two quantities described by the same UCD
Q | arith.zp | Zero point
S | em | Electromagnetic spectrum
S | em.IR | Infrared part of the spectrum
S | em.IR.15-30um | Infrared between 15 and 30 micron
S | em.IR.3-4um | Infrared between 3 and 4 micron
S | em.IR.30-60um | Infrared between 30 and 60 micron
S | em.IR.4-8um | Infrared between 4 and 8 micron
S | em.IR.60-100um | Infrared between 60 and 100 micron
S | em.IR.8-15um | Infrared between 8 and 15 micron
S | em.IR.H | Infrared between 1.5 and 2 micron
S | em.IR.J | Infrared between 1.0 and 1.5 micron
S | em.IR.K | Infrared between 2 and 3 micron
S | em.UV | Ultraviolet part of the spectrum
S | em.UV.10-50nm | Ultraviolet between 10 and 50 nm
S | em.UV.100-200nm | Ultraviolet between 100 and 200 nm
S | em.UV.200-300nm | Ultraviolet between 200 and 300 nm
S | em.UV.50-100nm | Ultraviolet between 50 and 100 nm
S | em.X-ray | X-ray part of the spectrum
S | em.X-ray.hard | Hard X-ray (12 - 120 keV)
S | em.X-ray.medium | Medium X-ray (2 - 12 keV)
S | em.X-ray.soft | Soft X-ray (0.2 - 2 keV)
Q | em.energy | Energy value in the em frame
Q | em.freq | Frequency value in the em frame
S | em.gamma | Gamma rays part of the spectrum
S | em.gamma.hard | Hard gamma ray (>500 keV)
S | em.gamma.soft | Soft gamma ray (120 - 500 keV)
S | em.line | Designation of major atomic and molecular lines
S | em.line.HI | 21cm hydrogen line
S | em.line.Brgamma | Bracket gamma line
S | em.line.Halpha | H-alpha line
S | em.line.Hbeta | H-beta line
S | em.line.Hgamma | H-gamma line
S | em.line.OIII | [OIII] line
S | em.mm | Millimetric part of the spectrum
S | em.mm.100-200GHz | Millimetric between 100 and 200 GHz
S | em.mm.1500-3000GHz | Millimetric between 1500 and 3000 GHz
S | em.mm.200-400GHz | Millimetric between 200 and 400 GHz
S | em.mm.30-50GHz | Millimetric between 30 and 50 GHz
S | em.mm.400-750GHz | Millimetric between 400 and 750 GHz
S | em.mm.50-100GHz | Millimetric between 50 and 100 GHz
S | em.mm.750-1500GHz | Millimetric between 750 and 1500 GHz
S | em.opt | Optical part of the spectrum
S | em.opt.B | Optical band between 400 and 500 nm
S | em.opt.I | Optical band between 750 and 1000 nm
S | em.opt.R | Optical band between 600 and 750 nm
S | em.opt.U | Optical band between 300 and 400 nm
S | em.opt.V | Optical band between 500 and 600 nm
S | em.radio | Radio part of the spectrum
S | em.radio.100-200MHz | Radio between 100 and 200 MHz
S | em.radio.12-30GHz | Radio between 12 and 30 GHz
S | em.radio.1500-3000MHz | Radio between 1500 and 3000 MHz
S | em.radio.20-100MHz | Radio between 20 and 100 MHz
S | em.radio.200-400MHz | Radio between 200 and 400 MHz
S | em.radio.3-6GHz | Radio between 3 and 6 GHz
S | em.radio.400-750MHz | Radio between 400 and 750 MHz
S | em.radio.6-12GHz | Radio between 6 and 12 GHz
S | em.radio.750-1500MHz | Radio between 750 and 1500 MHz
Q | em.wavenumber | Wavenumber value in the em frame
Q | em.wl | Wavelength value in the em frame
Q | em.wl.central | Central wavelength
Q | em.wl.effective | Effective wavelength
Q | instr | Instrument
E | instr.background | Instrumental background
Q | instr.bandpass | Bandpass (e.g.: band name) of instrument
Q | instr.bandwidth | Bandwidth of the instrument
Q | instr.baseline | Baseline for interferometry
S | instr.beam | Beam
Q | instr.calib | Calibration parameter
S | instr.det | Detector
Q | instr.det.noise | Instrument noise
Q | instr.det.psf | Point Spread Function
Q | instr.det.qe | Quantum efficiency
Q | instr.dispersion | Dispersion of a spectrograph
Q | instr.filter | Filter
Q | instr.filter.transm | Filter transmission
S | instr.fov | Field of view
S | instr.obsty | Observatory, satellite, mission
Q | instr.obsty.seeing | Seeing
Q | instr.offset | Offset angle respect to main direction of observation
Q | instr.order | Spectral order in a spectrograph
Q | instr.param | Various instrumental parameters
S | instr.pixel | Pixel
S | instr.plate | Photographic plate
Q | instr.plate.emulsion | Plate emulsion
Q | instr.precision | Instrument precision
Q | instr.saturation | Instrument saturation threshold
Q | instr.scale | Instrument scale (for CCD, plate, image)
Q | instr.sensitivity | Instrument sensitivity, detection threshold
Q | instr.setup | Instrument configuration or setup
Q | instr.skyLevel | Sky level
Q | instr.skyTemp | Sky temperature
Q | instr.tel | Telescope
Q | instr.tel.focalLength | Telescope focal length
P | meta | Metadata
P | meta.bib | Bibliographic reference
P | meta.bib.author | Author name
P | meta.bib.bibcode | Bibcode
P | meta.bib.fig | Figure in a paper
P | meta.bib.journal | Journal name
P | meta.bib.page | Page number
P | meta.bib.volume | Volume number
P | meta.code | Code or flag
P | meta.code.class | Classification code
P | meta.code.error | limit uncertainty error flag
P | meta.code.member | Membership code
P | meta.code.mime | MIME type
P | meta.code.multip | Multiplicity or binarity flag
P | meta.code.qual | Quality, precision, reliability flag or code
P | meta.cryptic | Unknown or impossible to understand quantity
P | meta.curation | Identity of man/organization responsible for the data
Q | meta.dataset | Dataset
S | meta.file | File
S | meta.fits | FITS standard
P | meta.id | Identifier, name or designation
P | meta.id.assoc | Identifier of associated counterpart
P | meta.id.cross | Cross identification
P | meta.id.parent | Identification of parent source
P | meta.id.part | Part of identifier, suffix or sub-component
S | meta.main | Main value of something
S | meta.modelled | Quantity was produced by a model
P | meta.note | Note or remark (longer than a code or flag)
P | meta.number | Number (of things; e.g. nb of object in an image)
P | meta.record | Record number
P | meta.ref | Reference, or origin
P | meta.ref.url | URL, web address
S | meta.software | Software used in generating data
S | meta.table | Table or catalogue
P | meta.title | Title or explanation
Q | meta.ucd | UCD
P | meta.unit | Unit
P | meta.version | Version
S | obs | Observation
Q | obs.airMass | Airmass
S | obs.atmos | Atmosphere
Q | obs.atmos.extinction | Atmospheric extinction
Q | obs.atmos.refractAngle | Atmospheric refraction angle
S | obs.calib | Calibration observation
S | obs.field | Region covered by the observation
S | obs.image | Image
Q | obs.observer | Observer, discoverer
Q | obs.param | Various observation or reduction parameter
E | phot | Photometry
E | phot.antennaTemp | Antenna temperature
Q | phot.calib | Photometric calibration
C | phot.color | Color index or magnitude difference
Q | phot.color.excess | color excess
Q | phot.color.reddFree | Dereddened color
E | phot.count | Flux expressed in counts
E | phot.fluence | fluence
E | phot.flux | Photon flux
Q | phot.flux.bol | Bolometric flux
E | phot.flux.sb | Flux surface brightness
E | phot.fluxDens | Flux density (per wl/freq/energy interval)
E | phot.fluxDens.sb | Flux density surface brightness
E | phot.limbDark | Limb-darkening coefficients
E | phot.mag | Photometric magnitude
Q | phot.mag.bc | Bolometric correction
Q | phot.mag.bol | Bolometric magnitude
Q | phot.mag.distMod | Distance modulus
E | phot.mag.reddFree | Dereddened magnitude
E | phot.mag.sb | Surface brightness in magnitude units
Q | phys | Physical quantities
Q | phys.SFR | Star formation rate
E | phys.absorption | Extinction or absorption along the line of sight
Q | phys.absorption.coeff | Absorption coefficient (e.g. in a spectral line)
Q | phys.absorption.gal | Galactic extinction
Q | phys.absorption.opticalDepth | Optical depth
Q | phys.abund | Abundance
Q | phys.abund.Fe | Fe/H abundance
Q | phys.abund.X | Hydrogen abundance
Q | phys.abund.Y | Helium abundance
Q | phys.abund.Z | Metallicity abundance
Q | phys.acceleration | Acceleration
Q | phys.albedo | Albedo or reflectance
Q | phys.angArea | Angular area
Q | phys.angMomentum | Angular momentum
V | phys.angSize | Angular size width diameter dimension extension major minor axis extraction radius
Q | phys.angSize.smajAxis | angular size extent or extension of semi-major axis
Q | phys.angSize.sminAxis | angular size extent or extension of semi-minor axis
Q | phys.area | Area (in linear units)
Q | phys.at | Atomic physics
Q | phys.at.collStrength | Collisional strength
Q | phys.at.damping | Atomic damping quantities (van der Waals)
Q | phys.at.lande | Lande factor
Q | phys.at.number | Atomic number Z
Q | phys.at.oscStrength | Oscillator strength
Q | phys.at.qn | Atomic quantum number
Q | phys.at.qn.I | Nuclear spin quantum number
Q | phys.at.radiationType | Type of radiation characterizing atomic lines (electric dipole/quadrupole, magnetic dipole)
Q | phys.at.term | Atomic term
Q | phys.at.transProb | Atomic transition probability, Einstein A coefficient
Q | phys.at.wOscStrength | Weighted oscillator strength
Q | phys.at.weight | Atomic weight
Q | phys.atmol | Atomic and molecular physics (shared properties)
Q | phys.atmol.branchingRatio | Branching ratio
Q | phys.atmol.coll | Related to collisions
Q | phys.atmol.configuration | Configuration
Q | phys.atmol.crossSection | Atomic / molecular cross-section
Q | phys.atmol.element | Element
Q | phys.atmol.excitation | Atomic molecular excitation parameter
Q | phys.atmol.final | Quantity refers to atomic/molecular final/ground state, level, ecc.
Q | phys.atmol.initial | Quantity refers to atomic/molecular initial state, level, ecc.
Q | phys.atmol.ion | Ion
S | phys.atmol.ionization | Related to ionization
S | phys.atmol.level | Atomic level
Q | phys.atmol.lifetime | Lifetime of a level
Q | phys.atmol.lineShift | Line shifting coefficient
Q | phys.atmol.parity | Parity
Q | phys.atmol.sweight | Statistical weight
S | phys.atmol.trans | Transition between states
Q | phys.columnDensity | Column density
Q | phys.density | Density (of mass, electron, ...)
Q | phys.dielectric | Complex dielectric function
Q | phys.dispMeasure | Dispersion measure
V | phys.electField | Electric field
S | phys.electron | Electron
Q | phys.electron.degen | Electron degeneracy parameter
Q | phys.emissMeasure | Emission measure
Q | phys.emissivity | Emissivity
Q | phys.energy | Energy
Q | phys.energyDensity | Energy-density
Q | phys.eos | Equation of state
Q | phys.excitParam | Excitation parameter U
Q | phys.gauntFactor | Gaunt factor/correction
Q | phys.gravity | Surface gravity
Q | phys.ionizParam | Ionization parameter
Q | phys.ionizParam.coll | Collisional ionization
Q | phys.ionizParam.rad | Radiative ionization
E | phys.luminosity | Luminosity
Q | phys.luminosity.fun | Luminosity function
E | phys.magAbs | Absolute magnitude
Q | phys.magAbs.bol | Bolometric absolute magnitude
V | phys.magField | Magnetic field
Q | phys.mass | Mass
Q | phys.mass.light | Mass to light ratio
Q | phys.mass.loss | Mass loss
Q | phys.massYield | Mass yield
Q | phys.mol | Molecular data
Q | phys.mol.dipole | Molecular dipole
Q | phys.mol.dipole.electric | Molecular electric dipole moment
Q | phys.mol.dipole.magnetic | Molecular magnetic dipole moment
Q | phys.mol.dissociation | Molecular dissociation
Q | phys.mol.formationHeat | Formation heat for molecules
Q | phys.mol.qn | Molecular quantum numbers
Q | phys.mol.quadrupole | Molecular quadrupole
Q | phys.mol.quadrupole.electric | Molecular electric quadrupole moment
S | phys.mol.rotation | Molecular rotation
S | phys.mol.vibration | Molecular vibration
Q | phys.polarization | Polarization
Q | phys.polarization.rotMeasure | Rotation measure polarization
Q | phys.polarization.stokes | Stokes polarization
Q | phys.pressure | Pressure
Q | phys.recombination.coeff | Recombination coefficient
Q | phys.refractIndex | Refraction index
Q | phys.size | Size (not angular)
Q | phys.size.diameter | Diameter
Q | phys.size.radius | Radius
Q | phys.size.smajAxis | Linear semi major axis
Q | phys.size.sminAxis | Linear semi minor axis
Q | phys.temperature | Temperature
Q | phys.temperature.effective | Effective temperature
Q | phys.temperature.electron | Electron temperature
Q | phys.transmission | Transmission (of filter, instrument, ...)
V | phys.veloc | Space velocity
Q | phys.veloc.ang | Angular velocity
Q | phys.veloc.dispersion | Velocity dispersion
Q | phys.veloc.escape | Escape velocity
Q | phys.veloc.expansion | Expansion velocity
Q | phys.veloc.microTurb | Microturbulence velocity
Q | phys.veloc.orbital | Orbital velocity
Q | phys.veloc.pulsat | Pulsational velocity
Q | phys.veloc.rotat | Rotational velocity
Q | phys.veloc.transverse | Transverse / tangential velocity
Q | pos | Position and coordinates
Q | pos.angDistance | Angular distance, elongation
Q | pos.az | Position in alt-azimutal frame
Q | pos.az.alt | Alt-azimutal altitude
Q | pos.az.azi | Alt-azimutal azimut
Q | pos.az.zd | Alt-azimutal zenith distance
S | pos.barycenter | Barycenter
S | pos.bodyrc | Body related coordinates
S | pos.cartesian | Cartesian (rectangular) coordinates
Q | pos.cartesian.x | Cartesian coordinate along the x-axis
Q | pos.cartesian.y | Cartesian coordinate along the y-axis
Q | pos.cartesian.z | Cartesian coordinate along the z-axis
S | pos.cmb | Cosmic Microwave Background reference frame
Q | pos.dirCos | Direction cosine
V | pos.distance | Linear distance
S | pos.earth | Coordinates related to Earth
Q | pos.earth.altitude | Altitude, height above the Earth's surface
Q | pos.earth.lat | Latitude on Earth
Q | pos.earth.lon | Longitude on Earth
S | pos.ecliptic | Ecliptic coordinates
Q | pos.ecliptic.lat | Ecliptic latitude
Q | pos.ecliptic.lon | Ecliptic longitude
S | pos.eop | Earth orientation parameters
Q | pos.eop.nutation | Earth nutation
S | pos.errorEllipse | Positional error ellipse
Q | pos.ephem | Ephemeris
S | pos.eq | Equatorial coordinates
Q | pos.eq.dec | Declination in equatorial coordinates
Q | pos.eq.ha | Hour-angle
Q | pos.eq.ra | Right ascension in equatorial coordinates
Q | pos.eq.spd | South polar distance in equatorial coordinates
Q | pos.frame | Reference frame used for positions
S | pos.galactic | Galactic coordinates
Q | pos.galactic.lat | Latitude in galactic coordinates
Q | pos.galactic.lon | Longitude in galactic coordinates
S | pos.galactocentric | Galactocentric coordinate system
S | pos.geocentric | Geocentric coordinate system
Q | pos.healpix | Hierarchical Equal Area IsoLatitude Pixelization
S | pos.heliocentric | Heliocentric position coordinate (solar system bodies)
Q | pos.htm | Hierarchical Triangular Mesh
S | pos.lambert | Lambert projection
S | pos.lg | Local Group reference frame
S | pos.lsr | Local Standard of Rest reference frame
Q | pos.lunar | Lunar coordinates
Q | pos.lunar.occult | Occultation by lunar limb
Q | pos.parallax | Parallax
Q | pos.parallax.dyn | Dynamical parallax
Q | pos.parallax.phot | Photometric parallaxes
Q | pos.parallax.spect | Spectroscopic parallax
Q | pos.parallax.trig | Trigonometric parallax
Q | pos.phaseAng | Phase angle, e.g. elongation of earth from sun as seen from a third cel. object
V | pos.pm | Proper motion
Q | pos.posAng | Position angle of a given vector
V | pos.precess | Precession (in equatorial coordinates)
Q | pos.resolution | Angular resolution
Q | pos.satellite | Position/coordinates of satellite or planet
S | pos.supergalactic | Supergalactic coordinates
Q | pos.supergalactic.lat | Latitude in supergalactic coordinates
Q | pos.supergalactic.lon | Longitude in supergalactic coordinates
P | pos.wcs | WCS keywords
P | pos.wcs.cdmatrix | WCS CDMATRIX
P | pos.wcs.crpix | WCS CRPIX
P | pos.wcs.crval | WCS CRVAL
P | pos.wcs.ctype | WCS CTYPE
P | pos.wcs.naxes | WCS NAXES
P | pos.wcs.naxis | WCS NAXIS
P | pos.wcs.scale | WCS scale or scale of an image
Q | spect | Spectroscopy
Q | spect.doppler | Doppler parameter b
E | spect.index | Spectral index
E | spect.line | Spectral line
E | spect.line.asymmetry | Line asymmetry
E | spect.line.broad | Spectral line broadening
Q | spect.line.broad.Stark | Stark line broadening coefficient
E | spect.line.broad.Zeeman | Zeeman broadening
E | spect.line.eqWidth | Line equivalent width
E | spect.line.intensity | Line intensity
E | spect.line.profile | Line profile
E | spect.line.width | Spectral line fwhm
Q | spect.resolution | Spectral (or velocity) resolution
E | spect.dopplerVeloc | Radial velocity, derived from the shift of some spectral feature
E | spect.dopplerVeloc.radio | Radial velocity derived from a frequency shift using the radio convention
E | spect.dopplerVeloc.opt | Radial velocity derived from a wavelength shift using the optical convention
S | src | Observed source viewed on the sky
Q | src.class | Source classification (star, galaxy, cluster...)
Q | src.class.color | Color classification
Q | src.class.distance | Distance class e.g. Abell
Q | src.class.luminosity | Luminosity class
Q | src.class.richness | Richness class e.g. Abell
Q | src.class.starGalaxy | Star/galaxy discriminator, stellarity index
Q | src.class.struct | Structure classification e.g. Bautz-Morgan
Q | src.density | Density of sources
Q | src.ellipticity | Source ellipticity
Q | src.impactParam | Impact parameter
Q | src.morph | Morphology structure
Q | src.morph.param | Morphological parameter
Q | src.morph.scLength | Scale length for a galactic component (disc or bulge)
Q | src.morph.type | Hubble morphological type (galaxies)
Q | src.orbital | Orbital parameters
Q | src.orbital.eccentricity | Orbit eccentricity
Q | src.orbital.inclination | Orbit inclination
Q | src.orbital.meanAnomaly | Orbit mean anomaly
Q | src.orbital.meanMotion | Mean motion
Q | src.orbital.node | Ascending node
Q | src.orbital.periastron | Periastron
Q | src.redshift | Redshift
Q | src.redshift.phot | Photometric redshift
Q | src.sample | Sample
Q | src.spType | Spectral type MK
Q | src.var | Variability of source
E | src.var.amplitude | Amplitude of variation
Q | src.var.index | Variability index
Q | src.var.pulse | Pulse
Q | stat | Statistical parameters
Q | stat.Fourier | Fourier coefficient
Q | stat.Fourier.amplitude | Amplitude Fourier coefficient
P | stat.correlation | Correlation between two parameters
P | stat.covariance | Covariance between two parameters
P | stat.error | Statistical error
P | stat.error.sys | Systematic error
Q | stat.fit | Fit
P | stat.fit.chi2 | Chi2
P | stat.fit.dof | Degrees of freedom
P | stat.fit.goodness | Goodness or significance of fit
S | stat.fit.omc | Observed minus computed
Q | stat.fit.param | Parameter of fit
P | stat.fit.residual | Residual fit
P | stat.likelihood | Likelihood
S | stat.max | Maximum or upper limit
S | stat.mean | Mean, average value
S | stat.median | Median value
S | stat.min | Minimum or lowest limit
Q | stat.param | Parameter
P | stat.snr | Signal to noise ratio
P | stat.stdev | Standard deviation
Q | stat.value | Miscellaneous value
P | stat.variance | Variance
P | stat.weight | Statistical weight
Q | time | Time
Q | time.age | Age
Q | time.crossing | Crossing time
Q | time.epoch | Epoch, julian date
Q | time.equinox | Equinox
Q | time.expo | Exposure on-time, duration
Q | time.expo.end | End time of exposure
Q | time.expo.start | Start time of exposure
Q | time.interval | Interval of time
Q | time.lifetime | Lifetime
Q | time.obs | Observation on-time, duration
Q | time.obs.end | End time of observation
Q | time.obs.start | Start time of observation
Q | time.period | Period
Q | time.phase | Phase
Q | time.relax | Relaxation time
Q | time.resolution | Time resolution
Q | time.scale | Timescale
B Changes from previous versions
Changes from v0.1
Descriptions of the words were improved.
Designation of commonly used lines have been moved to em.line.*. As a consequence,
terms like em.IR.K.Brgamma or spect.index.Hbeta have been removed.
phys.at and phys.mol have been completely reorganized to improve
the overall description of this domain. A new branch phys.atmol has been introduced
to group concepts shared between phys.at and phys.mol.
The phot.color section was significantly simplified.
Missing nodes of the tree were added (e.g. em.gamma, em.mm, pos.sg).
Creation of new words: em.wavenumber, meta.ucd, stat.error.sys
Typos were corrected in em.opt.* units and a few other descriptions.
Changes from v0.2
Section 1.2 has been simplified
3 new syntax codes (E, C, V) have been introduced, and described in appendix A
