J17404+5243sdO
HS1739+5244 · 17:40:25.94 52:43:07.50 · Culpan knownhsd
χ²/N = 0.97
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
Results and provenance
Fit — Bamberg
| Teff [K] | 38708 ± 549 |
| log g | 5.861 ± 0.058 |
| log n(He)/n(H) | -2.761 ± 0.172 |
| reduced χ² | 0.968 over 745 points |
| radial velocity | -54.0 km s−1 |
| resolution (FWHM) | 2.00 Å |
| lines fitted | 15 |
| grids | HE-0.041.fits HE-0.125.fits HE-0.300.fits HE-0.550.fits +9 more |
| fitted | 04/09/2026 19:10:03 |
Observation
| telescope | SDSS 2.5-M |
| survey / programme | MWM / mwm_cb |
| field · MJD | 101155 · 60120 |
| date | 2023-06-25 |
| catalogid | 27021597903780230 |
| exposure | 2700 s in 3 |
| airmass | 1.23 |
| seeing (50%) | 1.43″ |
| E(B−V) | 0.028 |
| pipeline | v6_2_1 |
| S/N (classifier) | 42.9 |
| source file | spec-101155-60120-27021597903780230.fits |
Gaia astrometry
| Gaia DR3 source | 1416603466898656384 |
| parallax [mas] | 0.5609 ± 0.0314 |
| G | 15.160 |
| BP − RP | -0.493 |
| Gabs | 3.896 |
| μα [mas/yr] | -0.899 |
| μδ [mas/yr] | -8.315 |
| l, b | 80.175, 31.815 |
Published (Culpan et al. 2022)
| class (Culpan) | sdOB |
| class (SIMBAD) | sdB |
| Teff [K] | 36000 ± 900 |
| log g | 5.50 ± 0.10 |
| log y | -2.90 ± 0.40 |
| reference | 2003A&A...400..939E |
Classifier
DISPUTED
fitted Teff 36000 logg 5.5 logY -2.9 2003A&A...400..939E
auto: He II/He I 2.3, EW 0.35, Mg I b suggests a companion but Ca II does not (-2.2 sigma)
Fitted lines
| line | λ [Å] | shift [Å] | continuum at | ±avg | fitted over |
| Hβ | 4861.32 | -0.88 | -40.0, 40.0 | 5.0 | -45.0, 45.0 |
| Hγ | 4340.46 | -0.78 | -40.0, 36.8 | 4.5 | -43.0, 43.0 |
| Hδ | 4101.73 | -0.74 | -40.0, 31.6 | 4.2 | -43.0, 43.0 |
| Hε | 3970.07 | -0.72 | -28.0, 30.0 | 4.1 | -30.0, 35.0 |
| Hζ | 3889.05 | -0.70 | -20.0, 26.2 | 4.0 | -31.8, 32.0 |
| Hη | 3835.38 | -0.69 | -20.0, 14.6 | 4.0 | -20.7, 21.8 |
| Hθ | 3797.90 | -0.68 | -16.0, 16.0 | 3.9 | -15.6, 16.7 |
| Hι | 3770.63 | -0.68 | -13.0, 13.0 | 3.9 | -11.7, 11.6 |
| He II 4686 | 4685.70 | -0.84 | -11.9, 11.9 | 4.9 | -15.0, 13.8 |
| He II 5412 | 5411.52 | -0.97 | -15.0, 15.0 | 5.6 | -15.0, 15.0 |
| He II 4542 | 4541.59 | -0.82 | -15.0, 20.0 | 4.7 | -20.0, 20.0 |
| He II 4200 | 4199.84 | -0.76 | -23.5, 33.8 | 4.3 | -20.0, 20.0 |
| He I 4472 | 4471.60 | -0.81 | -15.0, 15.0 | 4.6 | -15.0, 15.0 |
| He I 4026 | 4026.29 | -0.73 | -24.2, 15.0 | 4.2 | -15.0, 15.0 |
| He I 4922 | 4921.93 | -0.89 | -15.0, 15.0 | 5.1 | -15.0, 15.0 |
Spectral energy distribution
Teff 38708 K · log g 5.861 · E(44−55) 0.042 · χ²r 0.11 over 39 bands
distance 1783 pc · parallax 0.5600 ± 0.0300 mas (5%) · R 0.1764 +0.0107 −0.0095 R☉ · M 0.825 +0.147 −0.124 M☉ — above the 0.47 canonical mass · L 63.0 +8.0 −6.8 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.