Each line in a file lists the following information for a given star:
| Field |
Columns [start, end] |
Field | Description | |
|---|---|---|---|---|
| 1 | 1 - 12 | ra1 | J2000 right ascension of the object at the time of the (r band) SDSS observation | |
| 2 | 13 - 24 | dec1 | J2000 declination of the object at the time of the (r band) SDSS observation | |
| 3 | 25 - 31 | run | SDSS run number, for details see EDR paper | |
| 4 | 32 - 38 | camcol | SDSS camera column, for details see EDR paper | |
| 5 | 39 - 45 | field | SDSS field number, for details see EDR paper | |
| 6 | 46 - 56 | flag_r1 | Image processing flag, for details see EDR paper | |
| 7 | 57 - 66 | flag_r2 | Image processing flag, for details see EDR paper | |
| 8 | 67 - 75 | pm_match | SDSS proper motion parameters | |
| 9 | 76 - 85 | pm_l | ||
| 10 | 86 - 95 | pm_b | ||
| 11 | 96 - 105 | pm_err | ||
| 12 | 106 - 112 | iso | An object with isolated flag (iso) set to 1 is not a part of a BLENDED "parent" object. | |
| 13 | 113 - 131 | objid | SDSS object ID | |
| 14 | 132 - 141 | rext | SFD value for Ar, the ISM dust extinction in the r band | |
| 15 | 142- 151 | u | SDSS photometry, ugriz psf magnitudes and corresponding errors | |
| 16 | 152 - 161 | g | ||
| 17 | 162 - 171 | r | ||
| 18 | 172 - 181 | i | ||
| 19 | 182 - 191 | z | ||
| 20 | 192 - 201 | uerr | ||
| 21 | 202 - 211 | gerr | ||
| 22 | 212 - 221 | rerr | ||
| 23 | 222 - 231 | ierr | ||
| 24 | 232 - 241 | zerr | ||
| 25 | 242 - 251 | um | best-fit model values for ugrizJHK magnitudes, based on SDSS-only fit | |
| 26 | 252 - 261 | gm | ||
| 27 | 262 - 271 | rm | ||
| 28 | 272 - 281 | im | ||
| 29 | 282 - 291 | zm | ||
| 30 | 292 - 301 | Jm | ||
| 31 | 302 - 311 | Hm | ||
| 32 | 312 - 321 | Km | ||
| 33 | 322 - 328 | bmod | best-fit stellar model with a range of 0-228 | |
| 34 | 329 - 334 | bar | best-fit absorption in the r-band with a range of 0.00-9.98 in increments of 0.02 | |
| 35 | 335 - 340 | brv | best-fit Rv with a range of 1.0-7.9 in increments of 0.1 | |
| 36 | 341 - 350 | bchi2 | best-fit chi2 per degree of freedom calculated from SDSS bands | |
| 37 | 351 - 357 | gi | intrinsic g-i value as calculated from bmod (for Covey et al. library) | |
| 38 | 358 - 365 | dist | best-fit distance as calculated from gi, bar and the r-band magnitude | |
| 39 | 366 - 377 | ra2 | J2000 right ascension of the object at the time of the (r band) 2MASS observation | |
| 40 | 378 - 389 | dec2 | J2000 declination of the object at the time of the (r band) 2MASS observation | |
| 41 | 390 - 397 | delta | difference between SDSS and 2MASS coordinates in arcsec | |
| 42 | 398 - 407 | J | 2MASS photometry, JHK psf magnitudes and corresponding errors | |
| 43 | 408 - 417 | H | ||
| 44 | 418 - 427 | K | ||
| 45 | 428 - 437 | Jerr | ||
| 46 | 438 - 447 | Herr | ||
| 47 | 448 - 457 | Kerr | ||
| 48 | 458 - 467 | um2 | best-fit photometry, ugrizJHK magnitudes calculated from all bands | |
| 49 | 468 - 477 | gm2 | ||
| 50 | 478 - 487 | rm2 | ||
| 51 | 488 - 497 | im2 | ||
| 52 | 498 - 507 | zm2 | ||
| 53 | 508 - 517 | Jm2 | ||
| 54 | 518 - 527 | Hm2 | ||
| 55 | 528 - 537 | Km2 | ||
| 56 | 538 - 544 | bmod2 | best-fit stellar model with a range of 0-228 | |
| 57 | 545 - 550 | bar2 | best-fit absorption in the r-band with a range of 0.00-9.98 in increments of 0.02 | |
| 58 | 551 - 556 | brv2 | best-fit Rv with a range of 1.0-7.9 in increments of 0.1 | |
| 59 | 557 - 566 | bchi22 | best-fit chi2 per degree of freedom calculated from ALL 8 bands | |
| 60 | 567 - 573 | gi2 | intrinsic g-i value as calculated from bmod2 | |
| 61 | 574 - 581 | dist2 | best-fit distance as calculated from gi2, bar2 and the r-band magnitude |
Data Description:
flag_r1, flag_r2, pm_match, pm_l, pm_b, pm_err - set to zero if not given
u, g, r, i, z, J, H, K, uerr, gerr, rerr, ierr, zerr, Jerr, Herr, Kerr - color bands are set to 999.9 and their respective errors are set to 9999.9 if the corresponding error is greater than 0.5 (or 1.5 for the u-band)
a, b, c, ellchi, elldf - error ellipse parameters (z=Ax^2+Bxy+Cy^2 where x spans models and y spans A_r). ellchi is the chi^2-value of the ellipse fit and elldf is the number of points in the ellipse. All are set to 9999 if a, b, c, or ellchi are over 1000 or elldf is over 30000. All set to 0 if bchi2 is over 200.
dist - distance to star in parsecs is calculated when intrinsic g-i is between 0.2 and 4 with an error less than 0.5, otherwise set to -1. Distance is computed using eqs. A2, A3 and A7 in Ivezić et al. 2008, for [Fe/H]=-0.4.
Mr = -0.14 + 14.32*gi -12.97*gi^2 + 6.127*gi^3 -1.267*gi^4 + 0.0967*gi^5 d = 10^(r - Mr - bar + 5)
The catalogs are distributed as a compressed (gzip) tar archive (1.4 GB, expands to 5.5 GB) (download).
This archive (SDSS2MASSfreeRv.tar.gz) contains 10 files for low-latitude SEGUE strips (limited to |b|<30 deg), which include data for about 10 million stars.
The archive with files in fits format can be downloaded from here.
| Filename | Number of stars | Size (MB) | fits file (MB) | Region boundaries |
|---|---|---|---|---|
| SDSS2MASS_freeRv_l50.dat | 1512698 | 900 | 400 | l = [48.5, 51.5], b = [-30, 30] |
| SDSS2MASS_freeRv_l70.dat | 1409732 | 800 | 400 | l = [68.5, 71.5], b = [-30, 30] |
| SDSS2MASS_freeRv_l90.dat | 1214700 | 700 | 300 | l = [92.5, 95.5], b = [-30, 30] |
| SDSS2MASS_freeRv_l110.dat | 1043093 | 600 | 300 | l = [108.5, 110.5], b = [-30, 30] |
| SDSS2MASS_freeRv_l130.dat | 737288 | 400 | 200 | l = [128.5, 131.5], b = [-30, 30] |
| SDSS2MASS_freeRv_l150.dat | 864902 | 500 | 200 | l = [148.5, 151.5], b = [-30, 30] |
| SDSS2MASS_freeRv_l178.dat | 776916 | 400 | 200 | l = [176.5, 179.5], b = [-30, 30] |
| SDSS2MASS_freeRv_l187.dat | 872184 | 500 | 200 | l = [185.5, 188.5], b = [-30, 30] |
| SDSS2MASS_freeRv_l200.dat | 819470 | 500 | 200 | l = [201.5, 204.5], b = [-30, 30] |
| SDSS2MASS_freeRv_l230.dat | 827129 | 500 | 200 | l = [227.5, 230.5], b = [-30, 30] |
** NOT ALL FITS ARE USABLE FOR SCIENTIFIC ANALYSIS: PLEASE READ THE PAPER! **