J16408+3636sdO

SDSSJ164050.80+363650.9 · 16:40:50.81 36:36:51.01 · Culpan knownhsd

χ²/N = 1.00

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]	45616 ± 1123
log g	5.466 ± 0.077
log n(He)/n(H)	-2.180 ± 0.096
reduced χ²	0.996 over 744 points
radial velocity	162.0 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 19:09:45

Observation

telescope	SDSS 2.5-M
survey / programme	boss
date	2011-09-24
exposure	3603 s in 8
pipeline	v5_13_2
S/N (classifier)	42.1
source file	spec-5197-55828-0638.fits

Gaia astrometry

Gaia DR3 source	1328110166899698816
parallax [mas]	-0.0867 ± 0.0667
G	17.352
μ_α [mas/yr]	-3.154
μ_δ [mas/yr]	-2.377
l, b	59.187, 41.097

Published (Culpan et al. 2022)

class (Culpan)	sdO
class (SIMBAD)	DAO/sdO
T_eff [K]	40061 ± 2000
log g	5.00 ± 0.20
log y	-1.71 ± 0.40
reference	2009PhDT.......273H

Classifier

AGREES

fitted Teff 40061 logg 5.0 logY -1.71 2009PhDT.......273H

auto: He II/He I 3.6, EW 0.63, Mg I b suggests a companion but Ca II does not (0.6 sigma)

Fitted lines

line	λ [Å]	shift [Å]	continuum at	±avg	fitted over
H_β	4861.32	2.63	-40.0, 40.0	5.0	-45.0, 45.0
H_γ	4340.46	2.35	-40.0, 36.8	4.5	-43.0, 43.0
H_δ	4101.73	2.22	-40.0, 31.6	4.2	-43.0, 43.0
H_ε	3970.07	2.15	-28.0, 30.0	4.1	-30.0, 35.0
H_ζ	3889.05	2.10	-20.0, 26.2	4.0	-31.8, 32.0
H_η	3835.38	2.07	-20.0, 14.6	4.0	-20.7, 21.8
H_θ	3797.90	2.05	-16.0, 16.0	3.9	-15.6, 16.7
H_ι	3770.63	2.04	-13.0, 13.0	3.9	-11.7, 11.6
He II 4686	4685.70	2.53	-11.9, 11.9	4.9	-15.0, 13.8
He II 5412	5411.52	2.92	-15.0, 15.0	5.6	-15.0, 15.0
He II 4542	4541.59	2.45	-15.0, 20.0	4.7	-20.0, 20.0
He II 4200	4199.84	2.27	-23.5, 33.8	4.3	-20.0, 20.0
He I 4472	4471.60	2.42	-15.0, 15.0	4.6	-15.0, 15.0
He I 4026	4026.29	2.18	-24.2, 15.0	4.2	-15.0, 15.0
He I 4922	4921.93	2.66	-15.0, 15.0	5.1	-15.0, 15.0