J08395+0308sdO

SDSSJ083935.90+030840.8 · 08:39:35.90 03:08:40.81 · Culpan knownhsd

χ²/N = 0.99

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

Observed spectrum in black, model in red, offset by line. Balmer series left, helium right.

Results and provenance

Fit — Bamberg

T_eff [K]	49530 ± 649
log g	5.876 ± 0.040
log n(He)/n(H)	-3.082 ± 0.189
reduced χ²	0.991 over 747 points
radial velocity	-134.0 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 19:07:59

Observation

telescope	SDSS 2.5-M
survey / programme	boss
date	2010-12-03
exposure	4504 s in 10
pipeline	v5_13_2
S/N (classifier)	60.3
source file	spec-3809-55533-0376.fits

Gaia astrometry

Gaia DR3 source	3080057529138425728
parallax [mas]	0.3525 ± 0.0666
G	16.559
G_abs	4.262
μ_α [mas/yr]	-3.840
μ_δ [mas/yr]	0.165
l, b	223.016, 25.404

Published (Culpan et al. 2022)

class (Culpan)	sdO
class (SIMBAD)	sdO
T_eff [K]	52891 ± 5000
log g	5.52 ± 0.20
log y	-2.72 ± 0.40
reference	2009PhDT.......273H

Classifier

AGREES

fitted Teff 52891 logg 5.52 logY -2.72 2009PhDT.......273H

auto: He II/He I 1.9, EW 0.29, Mg I b suggests a companion but Ca II does not (-0.6 sigma)

Fitted lines

line	λ [Å]	shift [Å]	continuum at	±avg	fitted over
H_β	4861.32	-2.17	-40.0, 40.0	5.0	-45.0, 45.0
H_γ	4340.46	-1.94	-40.0, 36.8	4.5	-43.0, 43.0
H_δ	4101.73	-1.83	-40.0, 31.6	4.2	-43.0, 43.0
H_ε	3970.07	-1.77	-28.0, 30.0	4.1	-30.0, 35.0
H_ζ	3889.05	-1.74	-20.0, 26.2	4.0	-31.8, 32.0
H_η	3835.38	-1.71	-20.0, 14.6	4.0	-20.7, 21.8
H_θ	3797.90	-1.70	-16.0, 16.0	3.9	-15.6, 16.7
H_ι	3770.63	-1.69	-13.0, 13.0	3.9	-11.7, 11.6
He II 4686	4685.70	-2.09	-11.9, 11.9	4.9	-15.0, 13.8
He II 5412	5411.52	-2.42	-15.0, 15.0	5.6	-15.0, 15.0
He II 4542	4541.59	-2.03	-15.0, 20.0	4.7	-20.0, 20.0
He II 4200	4199.84	-1.88	-23.5, 33.8	4.3	-20.0, 20.0
He I 4472	4471.60	-2.00	-15.0, 15.0	4.6	-15.0, 15.0
He I 4026	4026.29	-1.80	-24.2, 15.0	4.2	-15.0, 15.0
He I 4922	4921.93	-2.20	-15.0, 15.0	5.1	-15.0, 15.0

Spectral energy distribution

T_eff 49530 K · log g 5.876 · E(44−55) 0.034 · χ²_r 0.17 over 37 bands

distance 2837 pc · parallax 0.3500 ± 0.0700 mas (20%) · R 0.1234 +0.0290 −0.0195 R☉ · M 0.418 +0.230 −0.129 M☉ · L 82.6 +43.4 −24.2 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.