Information on Service 'LAMOST DR6 Medium Resolution Spectra Web'

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A form-based interface to the LAMOST6 medium resolution spectra

For a list of all services and tables belonging to this service's resource, see Information on resource 'LAMOST DR6 Spectra'

Overview

You can access this service using:

Coverage

2.3156 2.50285 eV

2011.81 2018.38

This resource is not (directly) published. This can mean that it was deemed too unimportant, for internal use only, or is just a helper for a published service. Equally likely, however, it is under development, abandoned in development or otherwise unfinished. Exercise some caution.

Other services provided on the underlying data include:

Input Fields

The following fields are available to provide input to the service (with some renderers, some of these fields may be unavailable):

NameTable Head DescriptionUnitUCD
ssa_dateObs Date Obs. Midpoint of exposure (MJD) d time.epoch
ssa_location Location ICRS location of aperture center deg pos.eq

Default Output Fields

The following fields are contained in the output by default. More fields may be available for selection; these would be given below in the VOTable output fields.

NameTable Head DescriptionUnitUCD
accref Product key Access key for the data N/A meta.ref.url;meta.dataset
datalink DL URL of a datalink document for this dataset. N/A meta.ref.url
location_dec Dec N/A deg pos.eq.dec;meta.main
location_ra RA N/A deg pos.eq.ra;meta.main
mime Type MIME type of the file served N/A meta.code.mime
ssa_aperture Aperture Angular diameter of aperture deg phys.angSize;instr.fov
ssa_dateObs Date Obs. Midpoint of exposure (MJD) d time.epoch
ssa_specend Band end Upper value of spectral coordinate m em.wl;stat.max
ssa_specstart Band start Lower value of spectral coordinate m em.wl;stat.min
ssa_targname Object Common name of object observed. N/A meta.id;src

VOTable Output Fields

The following fields are available in VOTable output. The verbosity level is a number intended to represent the relative importance of the field on a scale of 1 to 30. The services take a VERB argument. A field is included in the output if their verbosity level is less or equal VERB*10.

NameTable Head DescriptionUnitUCD Verb. Level
accref Product key Access key for the data N/A meta.ref.url;meta.dataset 1
mobsid Mobsid Unique identifier for the medium resolution spectrum (most of these have multiple observations and include a coadded spectrum). N/A meta.id;meta.main 1
ra Target RA ICRS right ascension for this object from input catalogue deg pos.eq.ra;meta.main 1
dec Target Dec ICRS declination for this object from input catalogue deg pos.eq.dec;meta.main 1
ssa_location Location ICRS location of aperture center deg pos.eq 5
ssa_dateObs Date Obs. Midpoint of exposure (MJD) d time.epoch 5
ssa_timeExt Exp. Time Exposure duration s time.duration 5
ssa_length Length Number of points in the spectrum N/A N/A 5
accsize File size Size of the data in bytes byte N/A 11
ssa_dstitle Title A compact and descriptive designation of the dataset. N/A meta.title;meta.dataset 15
ssa_creatorDID C. DID Dataset identifier assigned by the creator N/A meta.id 15
ssa_pubDID P. DID Dataset identifier assigned by the publisher N/A meta.ref.ivoid 15
ssa_cdate Proc. Date Processing/Creation date N/A time;meta.dataset 15
ssa_pdate Pub. Date Date last published. N/A N/A 15
ssa_bandpass Bandpass Bandpass (i.e., rough spectral location) of this dataset; this should be the most appropriate term from the vocabulary http://www.ivoa.net/rdf/messenger. N/A instr.bandpass 15
ssa_cversion C. Version Creator assigned version for this dataset (will be incremented when this particular item is changed). N/A meta.version;meta.dataset 15
ssa_targname Object Common name of object observed. N/A meta.id;src 15
ssa_targclass Ob. cls Object class (star, QSO,...; use Simbad object classification http://simbad.u-strasbg.fr/simbad/sim-display?data=otypes if at all possible) N/A src.class 15
ssa_redshift z Redshift of target object N/A src.redshift 15
ssa_targetpos Obj. pos Equatorial (ICRS) position of the target object. N/A pos.eq;src 15
ssa_snr SNR Median signal to noise ratio over all pixel, computed as flux/sqrt(variance) N/A stat.snr 15
ssa_aperture Aperture Angular diameter of aperture deg phys.angSize;instr.fov 15
ssa_specmid Mid. Band Midpoint of region covered in this dataset m instr.bandpass 15
ssa_specext Bandwidth Width of the spectrum m instr.bandwidth 15
ssa_specstart Band start Lower value of spectral coordinate m em.wl;stat.min 15
ssa_specend Band end Upper value of spectral coordinate m em.wl;stat.max 15
ssa_csysName Sys System RA and Dec are given in N/A N/A 15
ssa_spectralucd UCD(spectral) UCD of the spectral column in the spectra served; when you have wavelengths, use em.wl for vacuum wavelengths, em.wl;obs.atmos for air wavelengths. N/A meta.ucd 15
ssa_spectralunit unit(spectral) Unit of the spectral column N/A meta.unit 15
ssa_fluxucd UCD(flux) UCD of the flux column N/A meta.ucd 15
ssa_fluxunit unit(flux) Unit of the flux column N/A meta.unit 15
ssa_publisher Publisher Publisher of the datasets included here. N/A meta.curation 15
ssa_creator Creator Creator of the datasets included here. N/A N/A 15
ssa_collection Collection A short handle naming the collection this spectrum belongs to. N/A N/A 15
ssa_instrument Instrument Instrument or code used to produce these datasets N/A meta.id;instr 15
ssa_datasource Src Method of generation for the data (one of survey, pointed, theory, custom, artificial). N/A N/A 15
ssa_creationtype Using Process used to produce the data (archival, cutout, filtered, mosaic, projection, spectralExtraction, or catalogExtraction) N/A N/A 15
ssa_reference Ref. URL or bibcode of a publication describing this data. N/A meta.bib.bibcode 15
ssa_fluxStatError Err. flux Statistical error in flux N/A stat.error;phot.flux.density;em 15
ssa_fluxSysError Sys. Err flux Systematic error in flux N/A stat.error.sys;phot.flux.density;em 15
ssa_fluxcalib Calib Flux Type of flux calibration (ABSOLUTE, CALIBRATED, RELATIVE, NORMALIZED, or UNCALIBRATED). N/A N/A 15
ssa_binSize Spect. Bin Bin size in wavelength m em.wl;spect.binSize 15
ssa_spectStatError Err. Spect Statistical error in wavelength m stat.error;em 15
ssa_spectSysError Sys. Err. Spect Systematic error in wavelength m stat.error.sys;em 15
ssa_speccalib Calib. Spect. Type of wavelength calibration N/A meta.code.qual 15
ssa_specres Spec. Res. Resolution (in meters of wavelength) on the spectral axis m spect.resolution;em.wl 15
ssa_spaceError Err. Spc Statistical error in position deg stat.error;pos.eq 15
ssa_spaceCalib Calib. Spc Type of calibration in spatial coordinates N/A meta.code.qual 15
ssa_spaceRes Res. Spc Spatial resolution of data deg pos.angResolution 15
obsid Obsid Unique identifier for the observation; LAMOST observations typically result in multiple spectra. N/A meta.id;obs 15
designation Target Target Designation (IAU style) N/A meta.id 15
ra_obs Fiber RA ICRS right ascension of the fiber pointing (can be different from ra for bright sources). deg pos.eq.ra 15
dec_obs Fiber Dec ICRS declination of the fiber pointing deg pos.eq.dec 15
objtype Ob. type Object type: star, k2star, fs, rvcandi, gal N/A meta.code.class 15
magtype Mag.Type Designation of the bands of the magnitudes in mag_arr; this is not easy to parse by a machine, sorry. N/A meta.code 15
mag_arr Mags. An array of derived magnitudes. See mag_types for the bands these magnitudes are intended for. N/A phot.mag 15
bad_b B bad? 1 if this is a problematic B spectrum. N/A meta.code 15
bad_r R bad? 1 if this is a problematic R spectrum. N/A meta.code 15
mime Type MIME type of the file served N/A meta.code.mime 20
ssa_model Model Data model name and version N/A N/A 20
ssa_timeSI [Time] Time conversion factor in Osuna-Salgado convention. N/A N/A 20
ssa_spectralSI [Spectral] Spectral conversion factor in Osuna-Salgado convention N/A N/A 20
ssa_fluxSI [Flux] Flux/magnitude conversion factor in Osuna-Salgado convention N/A N/A 20
ssa_dstype Data type Type of data (spectrum, time series, etc) N/A N/A 20
rv_b0 RV b0 Radial velocity estimated from the B spectrum after continuum removal. km/s spect.dopplerVeloc 20
rv_b0_err Err. RV b0 Error in rv_b0. km/s stat.error;spect.dopplerVeloc 20
rv_r0 RV r0 Radial velocity estimated from the R spectrum after continuum removal. km/s spect.dopplerVeloc 20
rv_r0_err Err. RV r0 Error in rv_r0. km/s stat.error;spect.dopplerVeloc 20
rv_br0 RV br0 Radial velocity estimated from the B and R spectra after continuum removal. km/s spect.dopplerVeloc 20
rv_br0_err Err. RV br0 Error in rv_br0. km/s stat.error;spect.dopplerVeloc 20
rv_lasp0 RV lasp0 Radial velocity estimated from the LAMOST stellar parameter pipeline. km/s spect.dopplerVeloc 20
rv_lasp0_err Err. RV lasp0 Error in rv_lasp0. km/s stat.error;spect.dopplerVeloc 20
rv_b1 RV b1 rv_b0 after zero-point correction km/s spect.dopplerVeloc 20
rv_b1_err Err. RV b1 Error in rv_b1. km/s stat.error;spect.dopplerVeloc 20
rv_r1 RV r1 rv_r0 after zero-point correction km/s spect.dopplerVeloc 20
rv_r1_err Err. RV r1 Error in rv_r1. km/s stat.error;spect.dopplerVeloc 20
rv_br1 RV br1 rv_br0 after zero-point correction km/s spect.dopplerVeloc 20
rv_br1_err Err. RV br1 Error in rv_br1. km/s stat.error;spect.dopplerVeloc 20
rv_lasp1 RV lasp1 rv_lasp0 after zero-point correction km/s spect.dopplerVeloc 20
rv_lasp1_err Err. RV lasp1 Error in rv_lasp1. km/s stat.error;spect.dopplerVeloc 20
rv_b_flag b ? Flag for RV extraction in the b band: 0 – no anomalies; 1 – too many bad pixels; 2 – radial velocity in excess of 450 km/s; 3 – low similarity with best-matched template. N/A meta.code.qual 20
rv_r_flag r ? Flag for RV extraction in the r band: 0 – no anomalies; 1 – too many bad pixels; 2 – radial velocity in excess of 450 km/s; 3 – low similarity with best-matched template. N/A meta.code.qual 20
rv_br_flag br ? Flag for RV extraction in the br band: 0 – no anomalies; 1 – too many bad pixels; 2 – radial velocity in excess of 450 km/s; 3 – low similarity with best-matched template. N/A meta.code.qual 20
owner Owner Owner of the data N/A N/A 25
embargo Embargo ends Date the data will become/became public yr N/A 25
planid Plan Identifier of the observation plan N/A meta.id;obs.proposal 25
spid SG id Identifier of the Spectragraph that took the source spectrum. N/A meta.id;instr 25
fiberid Fiber Identifier of the fiber used to take the source spectrum N/A meta.id;instr 25
fibertype Fiber Fiber Type of target (one of Obj, Sky, F-std, Unused, PosErr, Dead) N/A meta.code;instr 25
target_comment Comment Various comments (e.g., an external target id). N/A meta.note 25
offset_v Offset Offset of the observation from the target coordinate (these are added for bright objects to prevent saturation). arcsec instr.offset 25
coadd Coadd? 1 if this is a co-added spectrum N/A meta.code 25
fibermask Fiber prob Bitmask for fiber problems. See note for the meaning for the bits. Note fib N/A meta.code.qual 25
ssa_region Coverage Rough coverage based on location and aperture. N/A pos.outline;obs.field 30

Guoshoujing Telescope (the Large Sky Area Multi-Object Fiber Spectroscopic Telescope LAMOST) is a National Major Scientific Project built by the Chinese Academy of Sciences. Funding for the project has been provided by the National Development and Reform Commission. LAMOST is operated and managed by the National Astronomical Observatories, Chinese Academy of Sciences.

Please also see the LAMOST Data Policy.

Citation Info

VOResource XML (that's something exclusively for VO nerds)

Note fib

Meaning of the bits in fibermask (note: while upstream counts bits from 1, we count bits from 0):

Bit Meaning
0 Fiber not allotted
1 Bad trace from the TRACECENTER routine
2 Low counts in flat field
3 Bad arc solution
4 <10% pixels are bad on the CCD
5 <10% pixels are saturated
6 Whopping fiber
7 Near a whopping fiber
8 Sky fiber shows extreme residuals