J22226+0051sdO

PG2220+006 · 22:22:38.69 00:51:25.02 · 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]	52146 ± 1264
log g	5.747 ± 0.067
log n(He)/n(H)	-3.132 ± 0.061
reduced χ²	0.975 over 743 points
radial velocity	18.0 km s⁻¹
resolution (FWHM)	2.50 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 18:33:55

Fit — Lei (TLUSTY)

T_eff [K]	50190 ± 1050
log g	5.550 ± 0.080
log n(He)/n(H)	-3.090 ± 0.150
grids	Lei et al. 2019, ApJ 881, 135 SYNSPEC 49 spectra from NLTE TLUSTY 204 model atmospheres, through XTgrid

Observation

cosmic rays	6 pixels cancelled
S/N (classifier)	60.3
source file	spec-57336-EG222106N010205M01_sp04-121.fits.gz

Gaia astrometry

Gaia DR3 source	2679230771390593024
parallax [mas]	0.3135 ± 0.0611
G	16.287
G_abs	3.794
μ_α [mas/yr]	1.191
μ_δ [mas/yr]	-6.342
l, b	64.846, -44.589

Published (Culpan et al. 2022)

class (Culpan)	sdO
class (SIMBAD)	sdO
T_eff [K]	52261 ± 5000
log g	5.32 ± 0.20
log y	-2.84 ± 0.40
reference	2009PhDT.......273H

Classifier

AGREES

fitted Teff 52261 logg 5.32 logY -2.84 2009PhDT.......273H

auto: He II/He I 2.1, EW 0.32, Mg I b suggests a companion but Ca II does not (-0.7 sigma)

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 II 5412	5411.52	0.32	-15.0, 15.0	5.6	-15.0, 15.0
He II 4542	4541.59	0.27	-15.0, 20.0	4.7	-20.0, 20.0
He II 4200	4199.84	0.25	-23.5, 33.8	4.3	-20.0, 20.0
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