Northern Sample: Master File Format

Byte-by-byte Description of file:
Field (Column) Bytes Format Units Label Explanations
1 1- 18 A18 SDSS SDSS DR7 Object Designation (1)
2 19- 29 F11.6 deg RAdeg Right Ascension in decimal degrees (J2000)
3 30- 40 F11.6 deg DEdeg Declination in decimal degrees (J2000)
4 41- 47 F7.4 --- z Redshift
5 48- 54 F7.3 mag umag BEST SDSS u band PSF magnitude (2)
6 55- 60 F6.3 mag e_umag Error in umag
7 61- 67 F7.3 mag gmag BEST SDSS g band PSF magnitude (2)
8 68- 73 F6.3 mag e_gmag Error in gmag
9 74- 80 F7.3 mag rmag BEST SDSS r band PSF magnitude (2)
10 81- 86 F6.3 mag e_rmag Error in rmag
11 87- 93 F7.3 mag imag BEST SDSS i band PSF magnitude (2)
12 94- 99 F6.3 mag e_imag Error in imag
13 100-106 F7.3 mag zmag BEST SDSS z band PSF magnitude (2)
14 107-112 F6.3 mag e_zmag Error in zmag
15 113-119 F7.3 mag Au Galactic extinction in u filter (3)
16 120-126 F7.3 [cm-2] logNH Log of Galactic H I column density
17 127-133 F7.3 mag F20 FIRST Peak 20 cm flux density (4)
18 134-141 F8.3 --- q_F20 Signal-to-ratio for F20
19 142-148 F7.3 arcsec S-F SDSS/FIRST separation
20 149-156 F8.3 [ct/s] logCR RASS BSC/FSC full band count rate (5)
21 157-163 F7.3 --- q_logCR Signal-to-ratio for logCR
22 164-170 F7.3 arcsec S-R SDSS/RASS separation
23 171-177 F7.3 mag Jmag 2MASS J band magnitude (6)
24 178-183 F6.3 mag e_Jmag Error in Jmag
25 184-190 F7.3 mag Hmag 2MASS H band magnitude (6)
26 191-196 F6.3 mag e_Hmag Error in Hmag
27 197-203 F7.3 mag Kmag 2MASS K band magnitude (6)
28 204-209 F6.3 mag e_Kmag Error in Kmag
29 210-216 F7.3 arcsec S-S SDSS/2MASS separation
30 217-219 I3 --- 2Flgs 2MASS Flag (7)
31 220-227 F8.3 mag iMag Absolute SDSS i band magnitude (8)
32 228-234 F7.3 mag Del(g-i) The (g-i) color offset (9)
33 235-237 I3 --- MFlg Morphology flag (10)
34 238-240 I3 --- SciFlg SCIENCEPRIMARY flag (11)
35 241-243 I3 --- SMflg SDSS MODE flag (12)
36 244-246 I3 --- Uflg Uniform target selection flag (13)
37 247-258 I12 --- Bflg Target selection flag; BEST
38 259-261 I3 --- BLow-z Low-z Quasar, color selection only, target flag (14)
39 262-264 I3 --- BHi-z High-z Quasar, color selection only, target flag (14)
40 265-267 I3 --- BFTflg FIRST target flag (14)
41 268-270 I3 --- BRTflg ROSAT target flag (14)
42 271-273 I3 --- BSeren Serendipity target flag (14)
43 274-276 I3 --- BStarflg Star target flag (14)
44 277-279 I3 --- BGalflg Galaxy target flag (14)
45 280-285 I6 --- Run SDSS Imaging Run Number for photometric measurements
46 286-291 I6 d MJD-I Modified Julian Date of imaging observation
47 292-297 I6 d MJD-S Modified Julian Date of spectroscopic observation
48 298-302 I5 --- Plate Spectroscopic Plate Number
49 303-307 I5 --- Fiber Spectroscopic Fiber Number
50 308-311 I4 --- ReRun SDSS Photometric Processing Rerun Number
51 312-314 I3 --- Camera SDSS Camera Column Number
52 315-319 I5 --- Frame SDSS Frame Number
53 320-324 I5 --- Object SDSS Object Number
54 325-336 I12 --- Tflg Target selection flag; TARGET
55 337-339 I3 --- TLow-z Low-z Quasar, color selection only, target flag (14)
56 340-342 I3 --- THi-z High-z Quasar, color selection only, target flag (14)
57 343-345 I3 --- TFTflg FIRST target flag (14)
58 346-348 I3 --- TRTflg ROSAT target flag (14)
59 349-351 I3 --- TSeren Serendipity target flag (14)
60 352-354 I3 --- TStarflg Star target flag (14)
61 355-357 I3 --- TGalflg Galaxy target flag (14)
62 358-364 F7.3 mag uTmag TARGET SDSS u band PSF magnitude (2)
63 365-370 F6.3 mag e_uTmag Error in uTmag
64 371-377 F7.3 mag gTmag TARGET SDSS g band PSF magnitude (2)
65 378-383 F6.3 mag e_gTmag Error in gTmag
66 384-390 F7.3 mag rTmag TARGET SDSS r band PSF magnitude (2)
67 391-396 F6.3 mag e_rTmag Error in rTmag
68 397-403 F7.3 mag iTmag TARGET SDSS i band PSF magnitude (2)
69 404-409 F6.3 mag e_iTmag Error in iTmag
70 410-416 F7.3 mag zTmag TARGET SDSS z band PSF magnitude (2)
71 417-422 F6.3 mag e_zTmag Error in zTmag
72 423-443 I21 --- ObjID BEST object ID; 64-bit integer
73 444-464 I21 --- SpecID Spectroscopic Object ID; 64-bit integer
74 465-490 A26 --- Name Previously published name (15)

Note (1): In the format hhmmss.ss+ddmmss.s (J2000; truncated coordinates).
Note (2): SDSS photometric measurements are asinh magnitudes (Lupton, Gunn,
    and Szalay 1999, AJ, 118, 1406) and are normalized (to ~3% accuracy)
    to the AB-magnitude system (Oke and Gunn 1983, ApJ, 266, 713).
    Uncorrected for Galactic extinction. A 0.000 indicates that the
    value couldn't be retrieved from the SDSS database.
Note (3): Where Ag, Ar, Ai, Az = 0.736, 0.534, 0.405, 0.287 x Au.
Note (4): As AB magnitude where AB mag = -2.5 log10 [f&nu / 3631 Jy].
    0.000 = no detection;
    -1.000 = not in FIRST survey area.
Note (5): X-ray data from ROSAT All Sky Survey Bright and Faint source catalogs
    -9.000 = no detection.
Note (6): All 2MASS data are from the 2MASS All-Sky Data Release Point Source
    Catalog (PSC) 2003 March 25. Note that 2MASS measurements are
    Vega-based, not AB, magnitudes.
    0.000 = no detection.
Note (7): Where 2Flgs = 9*JFLAG+3*HFLAG+KFLAG Individual filter flags:
    0 = No Detection;
    1 = Catalog Match;
    2 = New Photometry on Images.
Note (8): For Ho = 70.0, ΩM = 0.300, ΩL = 0.700, αQ = -0.50.
Note (9): In magnitudes of the quasar (g-i) from the mode of the distribution
    of (g-i) of quasars at this redshift. A value of -9.0 indicates too
    few quasars at redshift to form mean relation. All colors corrected
    for Galactic extinction.
Note (10):
    0 = point source;
    1 = extended.
Note (11):
    0 = Object is not SCIENCEPRIMARY;
    1 = Object is SCIENCEPRIMARY.
Note (12): for blends, overlapping scans.
    1 = Primary object;
    2 = Secondary observation;
    3 = Family observation.
Note (13):
    0 = not selected with final algorithm;
    1 = selected with final algorithm.
Note (14):
    0 = not targeted;
    1 = targeted.
Note (15): "SDSS" in this column indicates that the object is a previously
    published SDSS discovery.

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