J00002+1738

PG2357+174 · 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]	38907 ± 406
log g	6.171 ± 0.054
log n(He)/n(H)	-1.864 ± 0.087
reduced χ²	0.984 over 638 points
radial velocity	-40.0 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 18:24:44

Fit — Lei (TLUSTY)

T_eff [K]	36610 ± 810
log g	6.060 ± 0.130
log n(He)/n(H)	-1.850 ± 0.090
grids	Lei et al. 2019, ApJ 881, 135 SYNSPEC 49 spectra from NLTE TLUSTY 204 model atmospheres, through XTgrid

Observation

source file

spec-57691-EG000313N173308M01_sp03-166.fits.gz

Gaia astrometry

Gaia DR3 source	2773760665114010880
parallax [mas]	0.3100 ± 0.0746
G	16.520
μ_α [mas/yr]	6.713
μ_δ [mas/yr]	-2.658
l, b	106.009, -43.536

Published (Culpan et al. 2022)

class (Culpan)	sdOB
class (SIMBAD)	sdB
T_eff [K]	38462 ± 184
log g	6.02 ± 0.03
log y	-1.92 ± 0.05
reference	2021ApJS..256...28L

Fitted lines

line	λ [Å]	shift [Å]	continuum at	±avg	fitted over
H_β	4861.32	-0.65	-40.0, 40.0	5.0	-45.0, 45.0
H_γ	4340.46	-0.58	-40.0, 36.8	4.5	-43.0, 43.0
H_δ	4101.73	-0.55	-40.0, 31.6	4.2	-43.0, 43.0
H_ε	3970.07	-0.53	-28.0, 30.0	4.1	-30.0, 35.0
H_ζ	3889.05	-0.52	-20.0, 26.2	4.0	-31.8, 32.0
H_η	3835.38	-0.51	-20.0, 14.6	4.0	-20.7, 21.8
H_θ	3797.90	-0.51	-16.0, 16.0	3.9	-15.6, 16.7
H_ι	3770.63	-0.50	-13.0, 13.0	3.9	-11.7, 11.6
He II 4686	4685.70	-0.63	-11.9, 11.9	4.9	-15.0, 13.8
He I 4472	4471.60	-0.60	-15.0, 15.0	4.6	-15.0, 15.0
He I 4026	4026.29	-0.54	-24.2, 15.0	4.2	-15.0, 15.0
He I 4922	4921.93	-0.66	-15.0, 15.0	5.1	-15.0, 15.0