J07404+1551sdB
SDSSJJ074025.12+155155.0 · 07:40:25.13 15:51:55.12 · Culpan knownhsd
outside the grid χ²/N = 0.97
Spectrum
shaded: the intervals the fit used · │ a cancelled pixeldrag on either panel to zoom · dbl-click or Esc to reset · arrows to pan
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] | 39102 ± 2244 |
| log g | 7.322 ± 0.207 |
| log n(He)/n(H) | -3.140 ± 1.698 |
| reduced χ² | 0.966 over 610 points |
| radial velocity | -528.0 km s−1 |
| resolution (FWHM) | 2.50 Å |
| lines fitted | 12 |
| grids | HE-0.041.fits HE-0.125.fits HE-0.300.fits HE-0.550.fits +9 more |
| settled | outside the grid |
| fitted | 04/09/2026 18:28:43 |
Fit — Lei (TLUSTY)
| Teff [K] | 32430 ± 660 |
| log g | 6.210 ± 0.120 |
| log n(He)/n(H) | -3.000 ± 0.000 |
| grids | Lei et al. 2019, ApJ 881, 135 SYNSPEC 49 spectra from NLTE TLUSTY 204 model atmospheres, through XTgrid |
| helium | published as a limit |
Observation
| cosmic rays | 24 pixels cancelled |
| S/N (classifier) | 49.3 |
| source file | spec-57746-GAC115N15M1_sp03-225.fits.gz |
Gaia astrometry
| Gaia DR3 source | 3165813590653493760 |
| parallax [mas] | 0.4157 ± 0.0808 |
| G | 17.033 |
| Gabs | 5.072 |
| μα [mas/yr] | 0.805 |
| μδ [mas/yr] | -6.295 |
| l, b | 203.849, 17.832 |
Published (Culpan et al. 2022)
| class (Culpan) | sdOB |
| class (SIMBAD) | sdB |
| Teff [K] | 35914 ± 335 |
| log g | 6.17 ± 0.06 |
| log y | -3.07 ± 0.30 |
| reference | 2021ApJS..256...28L |
Classifier
DISPUTED
fitted Teff 35914 logg 6.17 logY -3.07 2021ApJS..256...28L
auto: contrast 0.03, within the 0.25 a subdwarf reaches at 32 kK, Mg I b suggests a companion but Ca II does not (0.1 sigma)
Fitted lines
| line | λ [Å] | shift [Å] | continuum at | ±avg | fitted over |
| Hβ | 4861.32 | -8.56 | -40.0, 40.0 | 5.0 | -45.0, 45.0 |
| Hγ | 4340.46 | -7.64 | -40.0, 36.8 | 4.5 | -43.0, 43.0 |
| Hδ | 4101.73 | -7.22 | -40.0, 31.6 | 4.2 | -43.0, 43.0 |
| Hε | 3970.07 | -6.99 | -28.0, 30.0 | 4.1 | -30.0, 35.0 |
| Hζ | 3889.05 | -6.85 | -20.0, 26.2 | 4.0 | -31.8, 32.0 |
| Hη | 3835.38 | -6.76 | -20.0, 14.6 | 4.0 | -20.7, 21.8 |
| Hθ | 3797.90 | -6.69 | -16.0, 16.0 | 3.9 | -15.6, 16.7 |
| Hι | 3770.63 | -6.64 | -13.0, 13.0 | 3.9 | -11.7, 11.6 |
| He II 4686 | 4685.70 | -8.25 | -11.9, 11.9 | 4.9 | -15.0, 13.8 |
| He I 4472 | 4471.60 | -7.88 | -15.0, 15.0 | 4.6 | -15.0, 15.0 |
| He I 4026 | 4026.29 | -7.09 | -24.2, 15.0 | 4.2 | -15.0, 15.0 |
| He I 4922 | 4921.93 | -8.67 | -15.0, 15.0 | 5.1 | -15.0, 15.0 |