J00031+2412sdB

SDSSJ000307.06+241211.6 · 00:03:07.06 24:12:11.63 · 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.

Line-profile fit — uli

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

Results and provenance

Fit — Bamberg

T_eff [K]	27537 ± 225
log g	5.574 ± 0.037
log n(He)/n(H)	-2.677 ± 0.076
reduced χ²	0.989 over 639 points
radial velocity	-92.0 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 19:07:08

Fit — uli

T_eff [K]	27994 ± 303
log g	5.477 ± 0.039
log n(He)/n(H)	-2.695 ± 0.073
reduced χ²	0.994 over 639 points
radial velocity	-92.0 km s⁻¹
resolution (FWHM)	2.00 Å
lines fitted	12
grids	h667.grid h909.grid h97.grid h99.grid +1 more
fitted	04/09/2026 18:34:25

Observation

telescope	SDSS 2.5-M
survey / programme	boss
date	2013-09-04
exposure	6301 s in 14
pipeline	v5_13_2
S/N (classifier)	63.2
source file	spec-6879-56539-0704.fits

Gaia astrometry

Gaia DR3 source	2849938472818734720
parallax [mas]	0.4415 ± 0.0627
G	16.356
G_abs	4.632
μ_α [mas/yr]	3.843
μ_δ [mas/yr]	2.689
l, b	109.036, -37.361

Published (Culpan et al. 2022)

class (Culpan)	sdB
class (SIMBAD)	sdB

Classifier

AGREES

auto: contrast 0.15, within the 0.30 a subdwarf reaches at 28 kK, Mg I b suggests a companion but Ca II does not (0.4 sigma)

Fitted lines

line	λ [Å]	shift [Å]	continuum at	±avg	fitted over
H_β	4861.32	-1.49	-40.0, 40.0	5.0	-45.0, 45.0
H_γ	4340.46	-1.33	-40.0, 36.8	4.5	-43.0, 43.0
H_δ	4101.73	-1.26	-40.0, 31.6	4.2	-43.0, 43.0
H_ε	3970.07	-1.22	-28.0, 30.0	4.1	-30.0, 35.0
H_ζ	3889.05	-1.19	-20.0, 26.2	4.0	-31.8, 32.0
H_η	3835.38	-1.18	-20.0, 14.6	4.0	-20.7, 21.8
H_θ	3797.90	-1.17	-16.0, 16.0	3.9	-15.6, 16.7
H_ι	3770.63	-1.16	-13.0, 13.0	3.9	-11.7, 11.6
He II 4686	4685.70	-1.44	-11.9, 11.9	4.9	-15.0, 13.8
He I 4472	4471.60	-1.37	-15.0, 15.0	4.6	-15.0, 15.0
He I 4026	4026.29	-1.24	-24.2, 15.0	4.2	-15.0, 15.0
He I 4922	4921.93	-1.51	-15.0, 15.0	5.1	-15.0, 15.0

Spectral energy distribution

T_eff 27537 K · log g 5.574 · E(44−55) 0.132 · χ²_r 0.37 over 36 bands

distance 2265 pc · parallax 0.4400 ± 0.0600 mas (14%) · R 0.1993 +0.0332 −0.0248 R☉ · M 0.544 +0.213 −0.139 M☉ · L 20.6 +7.4 −4.9 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.