J08301+4751sdB
PG0826+480 · 08:30:06.17 47:51:50.36 · Culpan knownhsd
χ²/N = 0.99
Spectrum
The whole reduced spectrum above, the region marked on it below. Shaded bands are the intervals the fit used; a tick under the axis marks a pixel the rejection mask cancelled.
Line-profile fit — Bamberg
Line-profile fit — uli
Results and provenance
Fit — Bamberg
| Teff [K] | 26008 ± 146 |
| log g | 5.573 ± 0.026 |
| log n(He)/n(H) | -3.570 ± 0.234 |
| reduced χ² | 0.988 over 638 points |
| radial velocity | -102.0 km s−1 |
| resolution (FWHM) | 2.00 Å |
| lines fitted | 12 |
| grids | HE-0.041.fits HE-0.125.fits HE-0.300.fits HE-0.550.fits +9 more |
| fitted | 04/09/2026 19:07:55 |
Fit — uli
| Teff [K] | 25956 ± 192 |
| log g | 5.455 ± 0.028 |
| log n(He)/n(H) | -3.219 ± 0.066 upper limit |
| reduced χ² | 0.986 over 638 points |
| radial velocity | -102.0 km s−1 |
| resolution (FWHM) | 2.00 Å |
| lines fitted | 12 |
| grids | h909.grid h97.grid h99.grid h999.grid |
| settled | outside the grid |
| fitted | 04/09/2026 18:35:00 |
Observation
| telescope | SDSS 2.5-M |
| survey / programme | boss |
| date | 2010-03-22 |
| exposure | 5405 s in 12 |
| pipeline | v5_13_2 |
| cosmic rays | 9 pixels cancelled |
| S/N (classifier) | 66.7 |
| source file | spec-3696-55277-0252.fits |
Gaia astrometry
| Gaia DR3 source | 930769616916994048 |
| parallax [mas] | 0.4775 ± 0.0538 |
| G | 16.040 |
| Gabs | 4.477 |
| μα [mas/yr] | -3.732 |
| μδ [mas/yr] | -7.062 |
| l, b | 171.808, 35.967 |
Published (Culpan et al. 2022)
| class (Culpan) | sdB+WD |
| class (SIMBAD) | sdB |
| Teff [K] | 25300 ± 600 |
| log g | 5.38 ± 0.06 |
| log y | -3.00 ± 0.00 |
| reference | 2015A&A...577A..26G |
Classifier
AGREES
fitted Teff 25300 logg 5.38 logY -3.0 2015A&A...577A..26G
auto: contrast 0.16, within the 0.30 a subdwarf reaches at 28 kK, Ca II 8662/8542 = 10.0 -- the star's own Paschen lines, not a companion
Fitted lines
| line | λ [Å] | shift [Å] | continuum at | ±avg | fitted over |
| Hβ | 4861.32 | -1.65 | -40.0, 40.0 | 5.0 | -45.0, 45.0 |
| Hγ | 4340.46 | -1.48 | -40.0, 36.8 | 4.5 | -43.0, 43.0 |
| Hδ | 4101.73 | -1.40 | -40.0, 31.6 | 4.2 | -43.0, 43.0 |
| Hε | 3970.07 | -1.35 | -28.0, 30.0 | 4.1 | -30.0, 35.0 |
| Hζ | 3889.05 | -1.32 | -20.0, 26.2 | 4.0 | -31.8, 32.0 |
| Hη | 3835.38 | -1.30 | -20.0, 14.6 | 4.0 | -20.7, 21.8 |
| Hθ | 3797.90 | -1.29 | -16.0, 16.0 | 3.9 | -15.6, 16.7 |
| Hι | 3770.63 | -1.28 | -13.0, 13.0 | 3.9 | -11.7, 11.6 |
| He II 4686 | 4685.70 | -1.59 | -11.9, 11.9 | 4.9 | -15.0, 13.8 |
| He I 4472 | 4471.60 | -1.52 | -15.0, 15.0 | 4.6 | -15.0, 15.0 |
| He I 4026 | 4026.29 | -1.37 | -24.2, 15.0 | 4.2 | -15.0, 15.0 |
| He I 4922 | 4921.93 | -1.67 | -15.0, 15.0 | 5.1 | -15.0, 15.0 |
Spectral energy distribution
Teff 26008 K · log g 5.573 · E(44−55) 0.038 · χ²r 0.16 over 36 bands
distance 2094 pc · parallax 0.4800 ± 0.0500 mas (10%) · R 0.1973 +0.0253 −0.0200 R☉ · M 0.531 +0.165 −0.116 M☉ · L 16.0 +4.4 −3.1 L☉
Photometry against the model, with the residual beneath it in units of the error. The horizontal bar on each point is the passband, not an error; a hollow point was not fitted and the tooltip says why. Drag a box to zoom, double-click or Esc to come back out.