J22174+1216sdO

PG2215+120 · 22:17:28.34 12:16:42.71 · Culpan knownhsd

χ²/N = 0.98

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]	41726 ± 279
log g	5.812 ± 0.031
log n(He)/n(H)	-2.313 ± 0.076
reduced χ²	0.982 over 748 points
radial velocity	136.0 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 19:10:51

Observation

telescope	SDSS 2.5-M
survey / programme	boss
date	2011-09-29
exposure	4504 s in 10
pipeline	v5_13_2
S/N (classifier)	60.6
source file	spec-5047-55833-0722.fits

Gaia astrometry

Gaia DR3 source	2727702466623387648
parallax [mas]	0.3551 ± 0.0626
G	16.067
G_abs	3.858
μ_α [mas/yr]	-8.755
μ_δ [mas/yr]	-24.883
l, b	74.429, -35.711

Published (Culpan et al. 2022)

class (Culpan)	sdOB
class (SIMBAD)	sdB
T_eff [K]	40100 ± 500
log g	5.60 ± 0.05
log y	-2.00 ± 0.20
reference	Geierprep

Classifier

DISPUTED

fitted Teff 40100 logg 5.6 logY -2.0 Geierprep

auto: He II/He I 4.1, EW 0.62, Mg I b suggests a companion but Ca II does not (-1.6 sigma)

Fitted lines

line	λ [Å]	shift [Å]	continuum at	±avg	fitted over
H_β	4861.32	2.21	-40.0, 40.0	5.0	-45.0, 45.0
H_γ	4340.46	1.97	-40.0, 36.8	4.5	-43.0, 43.0
H_δ	4101.73	1.86	-40.0, 31.6	4.2	-43.0, 43.0
H_ε	3970.07	1.80	-28.0, 30.0	4.1	-30.0, 35.0
H_ζ	3889.05	1.76	-20.0, 26.2	4.0	-31.8, 32.0
H_η	3835.38	1.74	-20.0, 14.6	4.0	-20.7, 21.8
H_θ	3797.90	1.72	-16.0, 16.0	3.9	-15.6, 16.7
H_ι	3770.63	1.71	-13.0, 13.0	3.9	-11.7, 11.6
He II 4686	4685.70	2.13	-11.9, 11.9	4.9	-15.0, 13.8
He II 5412	5411.52	2.45	-15.0, 15.0	5.6	-15.0, 15.0
He II 4542	4541.59	2.06	-15.0, 20.0	4.7	-20.0, 20.0
He II 4200	4199.84	1.91	-23.5, 33.8	4.3	-20.0, 20.0
He I 4472	4471.60	2.03	-15.0, 15.0	4.6	-15.0, 15.0
He I 4026	4026.29	1.83	-24.2, 15.0	4.2	-15.0, 15.0
He I 4922	4921.93	2.23	-15.0, 15.0	5.1	-15.0, 15.0

Spectral energy distribution

T_eff 41726 K · log g 5.812 · E(44−55) 0.072 · χ²_r 0.09 over 34 bands

distance 2816 pc · parallax 0.3600 ± 0.0600 mas (17%) · R 0.1822 +0.0392 −0.0273 R☉ · M 0.788 +0.397 −0.232 M☉ — above the 0.47 canonical mass · L 90.7 +43.3 −25.3 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.