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The SEGUE Stellar Parameter Pipeline 'sppParams' TableUp to SpectraSpectra for over 250,000 Galactic stars of all common spectral types are available with DR6. These Spectra were processed with a pipeline called the 'SEGUE Stellar Parameter Pipeline' (sspp) which computes standard stellar atmospheric parameters such as [Fe/H], log g and Teff for each star by a variety of methods. These outputs are stored in the CAS in a table called 'sppParams', indexed on the 'specObjID' key index parameter for queries joining to other tables such as specobjall and photoobjall. The fields available in the sppParams (also see sppParams description in CAS schema browser) table are:
n fieldName type/unit Description
0 specobjid int64 64 bit unique spectrum id f(plate,mjd,fiberid)
1 plate int plate number
2 mjd int Modified Julian Date of (last) observation for this plate/mjd combination
3 fiberid int Fiber number (1-640) 1-320 on spectrograph#1 321-640 on spectrograph#2
4 fehspectype char[4] SEGUE or SDSS target type abbreviations (type as targeted from photo)
AGB Asymtotic Giant Branch candidate star
BHB Blue Horizontal Branch candidate star
CVR Cool White Dwarf candidate star
FTO F turnoff candidate star
GAL SDSS main survey or LRG GALAXY candidate
GD G Dwarf candidate star
HOT HOT standard star (main SDSS Survey, g-r < 0)
KD K Dwarf candidate star
KG K Giant candidate star
LOW Low metalicity candidate star
MD M Dwarf candidate star
PHO Photometric Standard star (usually brighter F dwarf)
QA Quality Assurance target (in SEGUE, duplicates another fiber)
QSO SDSS main survey QSO candidate
RED Reddening Standard star (usually fainter F dwarf)
ROS may be F/G dwarf or MS/WD or low lat target
SER Serendip. Manual (1. globular/open cluster 2. High Prop motion)
STA Main SDSS survey STAR (not GAL or QSO or Standard)
SKY Sky fiber, should have no object flux
WD White Dwarf candidate fiber
5 sptypea char[4] Stellar Type Classification -- A
F0-F9, G0-G9, K0-K5, K7, M0-M9, L0-L8 NA
6 hammersptype char[5] Stellar Type Classification -- B
00, AGN, QSO, O, OB, A0, A0p, B6, B9, Car, CAR, CV, CWD,
F2, F5, F9 G0, G2, G5, K1, K3, K5, K7, M0V, M1-M8, L0, L1-L5,
L9, QSO, SBT, SFM, SKY, STA, T2, WD, WDm
7 flag char[5] SSPP flags
4 flags for each spectrum as a 4 char string 'abcd'.
xxxx = this is not a star, it's a Galaxy/QSO from SDSS main
n= all is normal for this flag position (one of four)
By position:
1. d, D, E, h, H, l, n, N, S, V
d: possible White Dwarf
D: apparent White Dwarf
E: Emission, possible QSO
h: Helium line detected
H: apparent Teff too Hot for parameter est.
l: Sodium line, possibly late type
N: Noise spectrum
S: Sky fiber -- no signal
V: Radial Velocity mismatch
2. C
Color mismatch (spectroscopic color Teff far from implied (g-r)_0
color Teff)
3. B
Balmer flag: unusual Balmer eq. widths for star
4. g
g band : unsual G-band eq. width for star Carbon star?
8 feha float/dex adopted [Fe/H] value -- if abs(fehr-fehw) < 0.15, feha=fehw, if not,
feha=(fehr + fehw)/2.0. If not available, set to -9.999
9 fehan int number of estimators. if feha=(fehr + fehw)/2.0, =1; if feha=fehw, =fehwn
10 fehaerr float/dex error/sigma on the [Fe/H] value. If not available, set to -9.999
11 fehw float/dex bi-weight [Fe/H] value from all available estimates of [Fe/H].
If not available, set to -9.999
12 fehwn int number of estimators for bi-weight averaging
13 fehwerr float/dex error/sigma on the [Fe/H] value. If not available, set to -9.999
14 fehr float/dex refined [Fe/H] from assorted estimates of [Fe/H] by comparing synthetic
spectra. If not available, set to -9.999
15 fehrn int number of estimators for calculating refine [Fe/H]
16 fehrerr float/dex error/sigma on the [Fe/H] value. If not available, set to -9.999
17 feh1 float/dex YoungSun's Kurucz grid 2 (NGS2 grid). If not available, set to -9.999
18 feh1n int indicator variable, =1 ok, =0 not used
19 feh1err float/dex error/sigma on the [Fe/H] value. If not available, set to -9.999
20 feh2 float/dex YoungSun's Kurucz grid 1 (NGS1 grid). If not available, set to -9.999
21 feh2n int indicator variable, =1 ok, =0 not used
22 feh2err float/dex error/sigma on the [Fe/H] value. If not available, set to -9.999
23 feh3 float/dex [Fe/H] from neural network method. If not available, set to -9.999
24 feh3n int indicator variable, =1 ok, =0 not used
25 feh3err float/dex error/sigma on the [Fe/H] value. If not available, set to -9.999
26 feh4 float/dex [Fe/H] from Ca II K method. If not available, set to -9.999
27 feh4n int indicator variable, =1 ok, =0 not used
28 feh4err float/dex error/sigma on the [Fe/H] value. If not available, set to -9.999
29 feh5 float/dex [Fe/H] from auto-correlation method. If not available, set to -9.999
30 feh5n int indicator variable, =1 ok, =0 not used
31 feh5err float/dex error/sigma on the [Fe/H] value. If not available, set to -9.999
32 feh6 float/dex [Fe/H] from Ca II triplet method. If not available, set to -9.999
33 feh6n int indicator variable, =1 ok, =0 not used
34 feh6err float/dex error/sigma on the [Fe/H] value. If not available, set to -9.999
35 feh7 float/dex [Fe/H] from Wilhelm, Beers, and Gray (1999) method. If not available,
set to -9.999
36 feh7n int indicator variable, =1 ok, =0 not used
37 feh7err float/dex error/sigma on the [Fe/H] value. If not available, set to -9.999
38 feh8 float/dex [Fe/H] from Carlos k24 grid. If not available, set to -9.999
39 feh8n int indicator variable, =1 ok, =0 not used
40 feh8err float/dex error/sigma on the [Fe/H] value. If not available, set to -9.999
41 feh9 float/dex [Fe/H] from Carlos ki13 grid. If not available, set to -9.999
42 feh9n int indicator variable, =1 ok, =0 not used
43 feh9err float/dex error/sigma on the [Fe/H] value. If not available, set to -9.999
44 teffa float/Kelvin Adopted Teff -- weighted mean of all available methods teff1-teff10
below. If not available, set to -9999
45 teffan int number of methods averaged
46 teffaerr float/K error/sigma on the Teff. If not available, set to -9999
47 teff1 float/K Teff from H alpha line. If not available, set to -9999
48 teff1n int indicator variable, =1 ok, =0 not used
49 teff1err float/K erorr/sigma on the Teff. If not available, set to -9999
50 teff2 float/K Teff from H delta line index. If not available, set to -9999
51 teff2n int indicator variable, =1 ok, =0 not used
52 teff2err float/K erorr/sigma on the Teff. If not available, set to -9999
53 teff3 float/K Teff from Kurucz models, based on colors. If not available, set to -9999
54 teff3n int indicator variable, =1 ok, =0 not used
55 teff3err float/K erorr/sigma on the Teff. If not available, set to -9999
56 teff4 float/K Teff from Girardi isochrones (2004). If not available, set to -9999
57 teff4n int indicator variable, =1 ok, =0 not used
58 teff4err float/K erorr/sigma on the Teff. If not available, set to -9999
59 teff5 float/K Teff from Ivezic et al. (2007) -- based on colors. If not available,
set to -9999
60 teff5n int indicator variable, =1 ok, =0 not used
61 teff5err float/K erorr/sigma on the Teff. If not available, set to -9999
62 teff6 float/K Teff from YoungSun's Kurucz grid 1 (NGC1 grid). If not available,
set to -9999
63 teff6n int indicator variable, =1 ok, =0 not used
64 teff6err float/K erorr/sigma on the Teff. If not available, set to -9999
65 teff7 float/K Teff from neural network method. If not available, set to -9999
66 teff7n int indicator variable, =1 ok, =0 not used
67 teff7err float/K erorr/sigma on the Teff. If not available, set to -9999
68 teff8 float/K Teff from Wilhelm, Beers, and Gray (1999) method. If not available,
set to -9999
69 teff8n int indicator variable, =1 ok, =0 not used
70 teff8err float/K erorr/sigma on the Teff. If not available, set to -9999
71 teff9 float/K Teff from Carlos k24 grid. If not available, set to -9999
72 teff9n int indicator variable, =1 ok, =0 not used
73 teff9err float/K erorr/sigma on the Teff. If not available, set to -9999
74 teff10 float/K Teff from Carlos ki13 grid. If not available, set to -9999
75 teff10n int indicator variable, =1 ok, =0 not used
76 teff10err float/K erorr/sigma on the Teff. If not available, set to -9999
77 logga float/dex Adopted log g -- weighted mean of all available methods logg1-logg8
below. If not available, set to -9.999
78 loggan int number of methods used
79 loggaerr float/dex error/sigma in the log g. If not available, set to -9.999
80 logg1 float/dex log g from YoungSun's Kurucz grid 2 (NGS2). If not available,
set to -9.999
81 logg1n int indicator variable, =1 ok, =0 not used
82 logg1err float/dex error/sigma in the log g. If not available, set to -9.999
83 logg2 float/dex log g from YoungSun's Kurucz grid 1 (NGS1). If not available,
set to -9.999
84 logg2n int indicator variable, =1 ok, =0 not used
85 logg2err float/dex error/sigma in the log g. If not available, set to -9.999
86 logg3 float/dex log g from neural netork method. If not available, set to -9.999
87 logg3n int indicator variable, =1 ok, =0 not used
88 logg3err float/dex error/sigma in the log g. If not available, set to -9.999
89 logg4 float/dex log g from from Ca I (4227 A) line index. If not available, set to -9.999
90 logg4n int indicator variable, =1 ok, =0 not used
91 logg4err float/dex error/sigma in the log g. If not available, set to -9.999
92 logg5 float/dex log g from MgH features (around 5170 A). If not available, set to -9.999
93 logg5n int indicator variable, =1 ok, =0 not used
94 logg5err float/dex error/sigma in the log g. If not available, set to -9.999
95 logg6 float/dex log g from Wilhelm, Beers, and Gray method (1999). If not available,
set to -9.999
96 logg6n int indicator variable, =1 ok, =0 not used
97 logg6err float/dex error/sigma in the log g. If not available, set to -9.999
98 logg7 float/dex log g from Carlos k24 grid. If not available, set to -9.999
99 logg7n int indicator variable, =1 ok, =0 not used
100 logg7err float/dex error/sigma in the log g. If not available, set to -9.999
101 logg8 float/dex log g from Carlos ki13 grid. If not available, set to -9.999
102 logg8n int indicator variable, =1 ok, =0 not used
103 logg8err float/dex error/sigma in the log g. If not available, set to -9.999
104 alphafe float/dex [alpha/Fe] from YoungSun's Kurucz grid 2 (NGS2). If not available,
set to -9.999 (experimental)
105 alphafen int indicator variable, =1 ok, =0 not used
106 alphafeerr float/dex error/sigam in [alpha/Fe]. If not available, set to -9.999
107 distV float/kpc distance to star if star is dwarf (Luminosity class V)
108 distTO float/kpc distance to star if star is turnoff star (class IV)
109 distIII float/kpc distance to star if star is giant (Lum class III)
110 distAGB float/kpc distance to star if star is on Asym giant branch
111 distHB float/kpc distance to star if star is on Horizontal Branch
112 distCAP float/kpc distance to star from Carlos model fits
113 unused1 float unused
114 distZ float/kpc distance to star in Z direction above Galactic plane
115 KPindex float/Angstroms Ca II K line index
116 GPindex float/Angstroms G band line index
117 unused2 float unused
118 RVflag char[32] RV flag, if ok, it says OK
119 rva float/km/s Adopted RV (usually Elodie) with +7.3m km/s offset added to fit known
clusters
THIS IS THE Radial Velocity to use in nearly all circumstances for stars
120 rvaerr float/km/s error in RV
121 calcrv float/km/s sspp calculated RV c=3e5 used throughout (i.e. not 299792.)
122 calcrverr float/km/s error in calcrv
123 bsrv float/km/s SpecBS RV -- based on templates taken from actual SDSS spectra,
zeropointed
124 bsrverr float/km/s SpecBS RV error
125 elodierv float/km/s ELODIE template match RV (best estimate if err not 0, > 20)
126 elodierverr float/km/s ELODIE RV error
127 unused3 float unused
128 unused4 float unused
129 velgal float/km/s Galactocentric radial velocity
130 g0 float/mag Dereddened psf magnitude in the g band. SFD(98) used to subtract
E(B-V)*3.793
131 V0 float/mag Derived V magnitude, V0, determined from g0 - 0.561((g-r)_0)-0.004
132 gmr0 float/mag Dereddened psf color (g-r)_0
133 grhbaa float/mag Adopted predicted (g-r)_0 from grbha, grbhd, grhp
134 grbha float/mag predicted (g-r)_0 from H alpha line index
135 grbhd float/mag predicted (g-r)_0 from H delta line index
136 grhp float/mag predicted (g-r)_0 from half power point
137 BmV0 float/mag (B-V)_0 derived from 0.916(g-r)+0.187
138 BmVBalmer0 float/mag (B-V)_0 derived from H balmer lines
139 umg0 float/mag Dereddened psf color (u-g)_0
140 rmi0 float/mag Dereddened psf color (r-i)_0
141 imz0 float/mag Dereddened psf color (i-z)_0
142 uerr float/mag Error in psf magnitude u band
143 gerr float/mag error in g
144 rerr float/mag error in r
145 ierr float/mag error in i
146 zerr float/mag error in z
147 ebv float E(B-V) at this (l,b) from SFD98
148 sna float Average Signal to noise ratio per pixel over 3950-6000 A
149 qualitycheck int Quality check integer
150 ra double/deg RA (J2000)
151 dec double/deg DEC (J2000)
152 l double/deg Galactic Longitude
153 b double/deg Galactic Latitude
154 chiHK float chi-square/dof measurement for the best fit to the spectrum in the
region of Ca H+K
155 chiGband float chi-square/dof measure for the best fit spectrum in the region of the
G band
156 chiMg float chi-square/dof measure for the best fit spectrum in the region of
Mg triplet
157 pmepoch double/years Proper motion epoch
158 pmmatch int Proper motion match to USNO-B catalog (1 = match, 0 =no match)
159 pmdelta float/arcsec distance the star has moved
160 pml float/mas/yr propermotion in the Galactic l direction
161 pmb float/mas/yr proper motion in the Galactic b direction
162 pmra float/mas/yr proper motion in ra
163 pmdec float/mas/yr proper motion in dec
164 pmraerr float/mas/yr error in pmra
165 pmdecerr float/mas/yr error in pmdec
166 pmsigra float sigma in ra ppm
167 pmsigdec float sigma in dec ppm
168 pmnfit int number of fits to the ppm
169 usnomag_u float/mag USNO-B mag of the star in the derived u band
170 usnomag_g float/mag USNO-B mag of the star in the derived g band
171 usnomag_r float/mag USNO-B mag of the star in the derived r band
172 usnomag_i float/mag USNO-B mag of the star in the derived i band
173 usnomag_z float/mag USNO-B mag of the star in the derived z band
174 pmdist20 float/mag distance to nearest star brighter than 20th
175 pmdist22 float/mag distance to nearest star brighter than 22nd
176 brun int Run number (best reduction of sky) from photoobjall table
177 brerun int Rerun number
178 bcamcol int Camcol (1-6 on 2.5m mosaic camera)
179 bfield int Field number
180 bobj int object number within field
181 zbsubclass char[32] specBS subclass
182 zbelodiesptype char[32] specBS ELODIE best match template type
183 lpar float/mag Newberg-Lenz "l" color, perpendicular to stellar locus, sensitive
to metalicity.
184 spar float/mag Ivezic (modified) s color, principal component
185 wpar float/mag Ivezic (modified) w color, principal component
186 p1spar float/mag Ivezic perpendicular to s color,component
187 zbclass char[32] SpecBS class
188 zbrchi2 float SpecBS rchi2 reduced chi-square per dof
189 zbdof float SpecBS dof measure for best fit template
190 zbvdisp float/km/s SpecBS Velocity dispersion (only relevant for GALaxies, not for stars)
191 zbvdisperr float/km/s SpecBS error in Velocity dispersion
192 zbzwarning int SpecBS warning flag
193 spec_cln char[32] Spectro1d(Chicago) classification 1= star, 6= red star, 0 = unknown
194 sprv float/km/s Spectro1d(Chicago) pipeline RV (also valid for Galaxies computed as cz)
195 sprverr float/km/s Spectro1d(Chicago) pipeline RV err
196 vel_dis float/km/s Spectro1d(Chicago) Velocity dispersion (only relevant for GALaxies,
not for stars)
197 vel_disperr float/km/s Spectro1d(Chicago) Velocity dispersion error
198 spz_conf float Spectro1d(Chicago) redshift confidence
199 spz_status int Spectro1d(Chicago) redshift status
200 spz_warning int Spectro1d(Chicago) redshift warning
201 eclass float Spectro1d(Chicago) Galaxy Principal component classification -
Andy Connolly
202 ecoeff1 float Spectro1d(Chicago) Principal component 1 (for Galaxies)
203 ecoeff2 float Spectro1d(Chicago) Principal component 2 (for Galaxies)
204 ecoeff3 float Spectro1d(Chicago) Principal component 3 (for Galaxies)
205 ecoeff4 float Spectro1d(Chicago) PC 4
206 ecoeff5 float Spectro1d PC5
207 inspect int Inspection flag (0 = sspp not manually inspected, yet)
-------------------------------------------------------------------------------------------------
Try this query in the CAS to get a feel for the columns:
select top 10 * from seguedr6..sppLines
Here's a sample query which selects low metalicity stars ([Fe/H] < -3.5)
which have relatively small error bars on the abundance (err < 0.5 dex)
and which are brighter than 19th mag (dereddened) and where more than three
different measures of feh are ok and are averaged.
select sp.plate,sp.mjd,sp.fiberid,sp.g0,sp.gmr0,
sl.caIIK,sl.caIIKerr,sl.caIIKmask,
sp.feha,sp.fehaerr,sp.fehan,sp.logga,sp.loggaerr,sp.loggan
from sppLines as sl, sppParams as sp where
feha < -3.5 and fehaerr between 0.01 and 0.5 and fehan > 3
and g0 < 19
and sl.specobjid = sp.specobjid
(3 stars returned)
Last modified: Tue Jun 26 15:05:55 CEST 2007 |