J07333+1744sdB

SDSSJ073323.77+174417.3 · 07:33:23.78 17:44:17.34 · 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.

Line-profile fit — uli

Observed spectrum in black, model in red, offset by line. Balmer series left, helium right.

Results and provenance

Fit — Bamberg

T_eff [K]	30383 ± 191
log g	5.976 ± 0.030
log n(He)/n(H)	-2.007 ± 0.041
reduced χ²	0.975 over 636 points
radial velocity	-113.0 km s⁻¹
resolution (FWHM)	2.00 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 19:07:36

Fit — uli

T_eff [K]	30641 ± 182
log g	5.874 ± 0.041
log n(He)/n(H)	-1.970 ± 0.044
reduced χ²	0.828 over 636 points
radial velocity	-113.0 km s⁻¹
resolution (FWHM)	2.00 Å
lines fitted	12
grids	h667.grid h909.grid h97.grid h99.grid +1 more
fitted	04/09/2026 18:34:48

Observation

telescope	SDSS 2.5-M
survey / programme	MWM / MWM
field · MJD	015073 · 59212
date	2020-12-27
catalogid	4542128886
exposure	12601 s in 14
airmass	1.06
seeing (50%)	1.61″
E(B−V)	0.023
pipeline	v6_2_1
cosmic rays	15 pixels cancelled
S/N (classifier)	80.5
source file	spec-015073-59212-4542128886.fits

Gaia astrometry

Gaia DR3 source	3170114884438433152
parallax [mas]	0.4279 ± 0.0685
G	16.591
BP − RP	-0.440
G_abs	4.761
μ_α [mas/yr]	-1.523
μ_δ [mas/yr]	-3.093
l, b	201.341, 17.053

Published (Culpan et al. 2022)

class (Culpan)	sdB
T_eff [K]	31065 ± 396
log g	6.32 ± 0.13
log y	-2.30 ± 0.08
reference	2021ApJS..256...28L

Classifier

AGREES

fitted Teff 31065 logg 6.32 logY -2.3 2021ApJS..256...28L

auto: contrast 0.07, within the 0.30 a subdwarf reaches at 28 kK, Mg I b suggests a companion but Ca II does not (-1.1 sigma)

Fitted lines

line	λ [Å]	shift [Å]	continuum at	±avg	fitted over
H_β	4861.32	-1.83	-40.0, 40.0	5.0	-45.0, 45.0
H_γ	4340.46	-1.64	-40.0, 36.8	4.5	-43.0, 43.0
H_δ	4101.73	-1.55	-40.0, 31.6	4.2	-43.0, 43.0
H_ε	3970.07	-1.50	-28.0, 30.0	4.1	-30.0, 35.0
H_ζ	3889.05	-1.47	-20.0, 26.2	4.0	-31.8, 32.0
H_η	3835.38	-1.45	-20.0, 14.6	4.0	-20.7, 21.8
H_θ	3797.90	-1.43	-16.0, 16.0	3.9	-15.6, 16.7
H_ι	3770.63	-1.42	-13.0, 13.0	3.9	-11.7, 11.6
He II 4686	4685.70	-1.77	-11.9, 11.9	4.9	-15.0, 13.8
He I 4472	4471.60	-1.69	-15.0, 15.0	4.6	-15.0, 15.0
He I 4026	4026.29	-1.52	-24.2, 15.0	4.2	-15.0, 15.0
He I 4922	4921.93	-1.86	-15.0, 15.0	5.1	-15.0, 15.0

Spectral energy distribution

T_eff 30383 K · log g 5.976 · E(44−55) 0.056 · χ²_r 0.15 over 26 bands

distance 2337 pc · parallax 0.4300 ± 0.0700 mas (16%) · R 0.1514 +0.0290 −0.0210 R☉ · M 0.793 +0.357 −0.220 M☉ — above the 0.47 canonical mass · L 17.6 +7.4 −4.6 L☉

Photometry against the model, with the residual beneath it in units of the error. The horizontal bar on each point is the passband, not an error; a hollow point was not fitted and the tooltip says why. Drag a box to zoom, double-click or Esc to come back out.