J07403+2049

SDSSJ074023.56+204937.0  ·  Culpan knownhsd

χ²/N = 0.96

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

profile fit on the Bamberg grid
Observed spectrum in black, model in red, offset by line. Balmer series left, helium right.

Line-profile fit — uli

profile fit on the uli grid
Observed spectrum in black, model in red, offset by line. Balmer series left, helium right.

Results and provenance

Fit — Bamberg

Teff [K]34242 ± 170
log g5.864 ± 0.021
log n(He)/n(H)-1.593 ± 0.029
reduced χ²0.960 over 639 points
radial velocity-157.0 km s−1
resolution (FWHM)2.00 Å
lines fitted12
gridsHE-0.041.fits
HE-0.125.fits
HE-0.300.fits
HE-0.550.fits
+9 more
fitted04/09/2026 19:07:39

Fit — uli

Teff [K]33700 ± 135
log g5.803 ± 0.022
log n(He)/n(H)-1.583 ± 0.025
reduced χ²0.956 over 639 points
radial velocity-157.0 km s−1
resolution (FWHM)2.00 Å
lines fitted12
gridsh667.grid
h909.grid
h97.grid
h99.grid
+1 more
fitted04/09/2026 18:34:49

Observation

cosmic rays3 pixels cancelled
source filespec-015286-59294-4543082495.fits

Gaia astrometry

Gaia DR3 source673058556816796288
parallax [mas]0.5609 ± 0.0528
G15.523
Gabs4.346
μα [mas/yr]-2.097
μδ [mas/yr]2.243
l, b199.030, 19.783

Published (Culpan et al. 2022)

class (Culpan)sdOB
class (SIMBAD)sdB0.2He10
Teff [K]33988 ± 916
log g5.78 ± 0.14
log y-1.70 ± 0.20
reference2017OAst...26..164G

Fitted lines

lineλ [Å]shift [Å]continuum at±avgfitted over
Hβ4861.32-2.55-40.0, 40.05.0-45.0, 45.0
Hγ4340.46-2.27-40.0, 36.84.5-43.0, 43.0
Hδ4101.73-2.15-40.0, 31.64.2-43.0, 43.0
Hε3970.07-2.08-28.0, 30.04.1-30.0, 35.0
Hζ3889.05-2.04-20.0, 26.24.0-31.8, 32.0
Hη3835.38-2.01-20.0, 14.64.0-20.7, 21.8
Hθ3797.90-1.99-16.0, 16.03.9-15.6, 16.7
Hι3770.63-1.97-13.0, 13.03.9-11.7, 11.6
He II 46864685.70-2.45-11.9, 11.94.9-15.0, 13.8
He I 44724471.60-2.34-15.0, 15.04.6-15.0, 15.0
He I 40264026.29-2.11-24.2, 15.04.2-15.0, 15.0
He I 49224921.93-2.58-15.0, 15.05.1-15.0, 15.0

Spectral energy distribution

Teff 34242 K · log g 5.864 · E(44−55) 0.022 · χ²r 0.63 over 10 bands

distance 1783 pc · parallax 0.5600 ± 0.0500 mas (9%) · R 0.1604 +0.0170 −0.0140 R☉ · M 0.687 +0.181 −0.135 M☉ — above the 0.47 canonical mass · L 31.9 +7.2 −5.4 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.