J22402+0206

PG2237+018 · 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.

Results and provenance

Fit — Bamberg

T_eff [K]	27231 ± 227
log g	5.431 ± 0.038
log n(He)/n(H)	-2.476 ± 0.090
reduced χ²	0.971 over 637 points
radial velocity	18.0 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 18:33:59

Fit — Lei (TLUSTY)

T_eff [K]	28280 ± 210
log g	5.380 ± 0.050
log n(He)/n(H)	-2.580 ± 0.110
grids	Lei et al. 2019, ApJ 881, 135 SYNSPEC 49 spectra from NLTE TLUSTY 204 model atmospheres, through XTgrid

Observation

source file

spec-57297-EG224242N000415B01_sp11-023.fits.gz

Gaia astrometry

Gaia DR3 source	2654860474117747200
parallax [mas]	0.5476 ± 0.0530
G	15.879
G_abs	4.668
μ_α [mas/yr]	3.890
μ_δ [mas/yr]	-5.040
l, b	70.458, -46.954

Published (Culpan et al. 2022)

class (Culpan)	sdB
class (SIMBAD)	sdB
T_eff [K]	25606 ± 500
log g	5.38 ± 0.05
log y	-1.92 ± 0.05
reference	2005A&A...430..223L

Fitted lines

line	λ [Å]	shift [Å]	continuum at	±avg	fitted over
H_β	4861.32	0.29	-40.0, 40.0	5.0	-45.0, 45.0
H_γ	4340.46	0.26	-40.0, 36.8	4.5	-43.0, 43.0
H_δ	4101.73	0.25	-40.0, 31.6	4.2	-43.0, 43.0
H_ε	3970.07	0.24	-28.0, 30.0	4.1	-30.0, 35.0
H_ζ	3889.05	0.23	-20.0, 26.2	4.0	-31.8, 32.0
H_η	3835.38	0.23	-20.0, 14.6	4.0	-20.7, 21.8
H_θ	3797.90	0.23	-16.0, 16.0	3.9	-15.6, 16.7
H_ι	3770.63	0.23	-13.0, 13.0	3.9	-11.7, 11.6
He II 4686	4685.70	0.28	-11.9, 11.9	4.9	-15.0, 13.8
He I 4472	4471.60	0.27	-15.0, 15.0	4.6	-15.0, 15.0
He I 4026	4026.29	0.24	-24.2, 15.0	4.2	-15.0, 15.0
He I 4922	4921.93	0.30	-15.0, 15.0	5.1	-15.0, 15.0