J21573+1159sdB

SDSSJ215722.90+115908.3 · 21:57:22.92 11:59:08.30 · 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]	35043 ± 401
log g	5.967 ± 0.053
log n(He)/n(H)	-2.056 ± 0.101
reduced χ²	0.980 over 635 points
radial velocity	13.0 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
fitted	04/09/2026 18:33:41

Fit — Lei (TLUSTY)

T_eff [K]	36080 ± 300
log g	5.930 ± 0.060
log n(He)/n(H)	-2.090 ± 0.150
grids	Lei et al. 2019, ApJ 881, 135 SYNSPEC 49 spectra from NLTE TLUSTY 204 model atmospheres, through XTgrid

Observation

S/N (classifier)	51.5
source file	spec-59875-EG220255N140221B02_sp02-116.fits.gz

Gaia astrometry

Gaia DR3 source	2728427319664072704
parallax [mas]	0.4831 ± 0.0551
G	16.448
G_abs	4.918
μ_α [mas/yr]	-9.594
μ_δ [mas/yr]	-1.591
l, b	69.973, -32.457

Published (Culpan et al. 2022)

class (Culpan)	sdOB
class (SIMBAD)	sdO
T_eff [K]	35382 ± 837
log g	5.94 ± 0.11
log y	-2.22 ± 0.25
reference	2019MNRAS.486.2169K

Classifier

DISPUTED

fitted Teff 35382 logg 5.94 logY -2.22 2019MNRAS.486.2169K

auto: contrast 0.03, within the 0.25 a subdwarf reaches at 32 kK

Fitted lines

line	λ [Å]	shift [Å]	continuum at	±avg	fitted over
H_β	4861.32	0.21	-40.0, 40.0	5.0	-45.0, 45.0
H_γ	4340.46	0.19	-40.0, 36.8	4.5	-43.0, 43.0
H_δ	4101.73	0.18	-40.0, 31.6	4.2	-43.0, 43.0
H_ε	3970.07	0.17	-28.0, 30.0	4.1	-30.0, 35.0
H_ζ	3889.05	0.17	-20.0, 26.2	4.0	-31.8, 32.0
H_η	3835.38	0.17	-20.0, 14.6	4.0	-20.7, 21.8
H_θ	3797.90	0.16	-16.0, 16.0	3.9	-15.6, 16.7
H_ι	3770.63	0.16	-13.0, 13.0	3.9	-11.7, 11.6
He II 4686	4685.70	0.20	-11.9, 11.9	4.9	-15.0, 13.8
He I 4472	4471.60	0.19	-15.0, 15.0	4.6	-15.0, 15.0
He I 4026	4026.29	0.17	-24.2, 15.0	4.2	-15.0, 15.0
He I 4922	4921.93	0.21	-15.0, 15.0	5.1	-15.0, 15.0