Data model: specObj

General description: This file contains the list of all spectra for a given data release, with associated parameters from the 2D and 1D pipelines for each.

Naming convention: specObj-[DRNAME].fits

Approximate size: 20 Mbytes.

File type: FITS

Read by products: sas

Written by products: sas

Required column names: (should be listed for Yanny and FITS)

• specObjID (int64): Unique ID
• targetID (int64): ID of Target
• bestObjID (int64): ID of best PhotoObj
• plateID (int64): Database ID of Plate
• specprimary (int16): Deemed to be science-worthy (defines default view SpecObj)
• firstRelease (string): Name of first release this object was associated with
• chunk (string): Chunk name
• survey (string): Survey name
• mjd (int32): MJD of observation (days)
• plate (int16): Plate number
• spec2dRerun (int32): Reduction version of spectrum
• tile (int32): Tile number
• designID (int32): Design ID number
• fiberID (int16): Fiber ID
• spectrographID (int16): which spectrograph (1,2) XXX
• objType (string): type of object targeted as
• class (string): Spectroscopic class (GALAXY, QSO, or STAR)
• subClass (string): Spectroscopic subclass XXX need page with details
• plug_ra (float64): Right ascension of fiber, J2000 (deg)
• plug_dec (float64): Declination of fiber, J2000 (deg)
• cx (float64): x of Normal unit vector in J2000
• cy (float64): y of Normal unit vector in J2000
• cz (float64): z of Normal unit vector in J2000
• xFocal (float32): X Focal XXX need in FITS (mm)
• yFocal (float32): Y Focal XXX need in FITS (mm)
• z (float32): Final Redshift
• zErr (float32): Redshift error
• rChi2 (float32): Reduced chi-squared of best fit
• DOF (float32): Degrees of freedom in best fit
• rChi2Diff (float32): Difference in reduced chi-squared between best and second best fit
• tFile (string): File name of best fit template source XXX should we store templates in a table?
• tColumn[10] (int16): Which column of the template file corresponds to each template
• nPoly (float32): Number of polynomial terms used in the fit
• theta[10] (float32): Coefficient for templates
• vdisp (float32): Velocity dispersion (km)
• vdisp_err (float32): Error in velocity dispersion (km)
• vdispz (float32): Redshift associated with best fit velocity dispersion
• vdispz_err (float32): Error in redshift associated with best fit velocity dispersion
• velDispChi2 (float32): Chi-squared associated with velocity dispersion fit
• velDispNPix (int32): Number of pixels overlapping best template in velocity dispersion fit
• velDispDOF (int32): Number of degrees of freedom in velocity dispersion fit
• waveMin (float32): Minimum observed (vacuum) wavelength (Angstroms)
• waveMax (float32): Maximum observed (vacuum) wavelength (Angstroms)
• wCoverage (float32): Coverage in wavelength, in units of log10 wavelength
• zWarning (int32): Bitmask of warning values; 0 means all is good XXX need page for description of this
• snMedian (float32): Median signal-to-noise over all good pixels
• chi68p (float32): 68-th percentile value of abs(chi) of the best-fit synthetic spectrum to the actual spectrum (around 1.0 for a good fit)
• fracNSigma[10] (float32): Fraction of pixels deviant by more than N sigma relative to best-fit
• fracNSigHi[10] (float32): Fraction of pixels high by more than N sigma relative to best-fit
• fracNSigLo[10] (float32): Fraction of pixels low by more than N sigma relative to best-fit
• anyAndMask (int32): for each bit, records whether any pixel in the spectrum has that bit set in its ANDMASK
• anyOrMask (int32): for each bit, records whether any pixel in the spectrum has that bit set in its ORMASK
• platesn2 (float32): Overall signal to noise measure for plate
• elodieFileName (string): File name for best-fit Elodie star
• elodieObject (string): Star name (mostly Henry Draper names)
• elodieSpType (string): Spectral type
• elodieBV (float32): (B-V) color (mag)
• elodieTEff (float32): Effective temperature (Kelvin)
• elodieLogG (float32): log10(gravity) XXX units ???
• elodieFeH (float32): Metallicity ([Fe/H])
• elodieZ (float32): Redshift
• elodieZErr (float32): Redshift error (negative for invalid fit)
• elodieZModelErr (float32): Standard deviation in redshift among the 12 best-fit stars
• elodieRChi2 (float32): Reduced chi^2
• elodieDOF (float32): Degrees of freedom for fit

Example file: specObj-testbed8.fits