J12471-0039sdB

PG1244-004 · 12:47:06.79 -00:39:25.78 · Culpan knownhsd

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

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]	43226 ± 381
log g	6.373 ± 0.041
log n(He)/n(H)	-3.887 ± 0.325
reduced χ²	0.972 over 640 points
radial velocity	-66.0 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 19:08:49

Fit — uli

T_eff [K]	41049 ± 383
log g	6.261 ± 0.050
log n(He)/n(H)	-3.330 ± 0.103 upper limit
reduced χ²	0.967 over 640 points
radial velocity	-66.0 km s⁻¹
resolution (FWHM)	2.00 Å
lines fitted	12
grids	h667.grid h909.grid h97.grid h99.grid +1 more
settled	outside the grid
fitted	04/09/2026 18:35:46

Observation

telescope	SDSS 2.5-M
survey / programme	boss
date	2010-01-18
exposure	8103 s in 18
pipeline	v5_13_2
cosmic rays	3 pixels cancelled
S/N (classifier)	67.7
source file	spec-3793-55214-0912.fits

Gaia astrometry

Gaia DR3 source	3683849391728631424
parallax [mas]	0.4881 ± 0.0731
G	16.436
G_abs	4.873
μ_α [mas/yr]	5.836
μ_δ [mas/yr]	-1.920
l, b	300.614, 62.195

Published (Culpan et al. 2022)

class (Culpan)	sdOB
class (SIMBAD)	sdBO
T_eff [K]	42775 ± 828
log g	5.98 ± 0.09
log y	-2.64 ± 0.32
reference	2021ApJS..256...28L

Classifier

DISPUTED

fitted Teff 42775 logg 5.98 logY -2.64 2021ApJS..256...28L

auto: contrast 0.01, within the 0.21 a subdwarf reaches at 35 kK, Mg I b suggests a companion but Ca II does not (-0.3 sigma)

Fitted lines

line	λ [Å]	shift [Å]	continuum at	±avg	fitted over
H_β	4861.32	-1.07	-40.0, 40.0	5.0	-45.0, 45.0
H_γ	4340.46	-0.96	-40.0, 36.8	4.5	-43.0, 43.0
H_δ	4101.73	-0.90	-40.0, 31.6	4.2	-43.0, 43.0
H_ε	3970.07	-0.87	-28.0, 30.0	4.1	-30.0, 35.0
H_ζ	3889.05	-0.86	-20.0, 26.2	4.0	-31.8, 32.0
H_η	3835.38	-0.84	-20.0, 14.6	4.0	-20.7, 21.8
H_θ	3797.90	-0.84	-16.0, 16.0	3.9	-15.6, 16.7
H_ι	3770.63	-0.83	-13.0, 13.0	3.9	-11.7, 11.6
He II 4686	4685.70	-1.03	-11.9, 11.9	4.9	-15.0, 13.8
He I 4472	4471.60	-0.98	-15.0, 15.0	4.6	-15.0, 15.0
He I 4026	4026.29	-0.89	-24.2, 15.0	4.2	-15.0, 15.0
He I 4922	4921.93	-1.08	-15.0, 15.0	5.1	-15.0, 15.0

Spectral energy distribution

T_eff 43226 K · log g 6.373 · E(44−55) 0.050 · χ²_r 0.42 over 40 bands

distance 2049 pc · parallax 0.4900 ± 0.0700 mas (14%) · R 0.1062 +0.0188 −0.0138 R☉ · M 0.974 +0.403 −0.256 M☉ — above the 0.47 canonical mass · L 35.5 +13.7 −8.7 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.