All names: SDSS J180940.41+234328.4, GALEX J180940.4+234328, Gaia DR2 4578402912401974656, 2MASS J18094040+2343287, SDSSJ180940.41+234328.4, TIC 285198260, Gaia DR3 4578402912401974656
| Parameter | Unit | Geier 2020 | Stilism | Simbad |
|---|---|---|---|---|
| Right ascension | 18 09 40.41 | 18 09 40.41 (0.02) | ||
| Declination | 23 43 28.40 | 23 43 28.55 (0.03) | ||
| Spectral type | sdB | sdB | ||
| Effective temperature | [K] | 28500.0 (300) | ||
| log(g) | [cgs] | 5.44 (0.06) | ||
| Mass | [M☉] | |||
| log(Luminosity) | [L☉] | |||
| Cooling age | [Gyr] | |||
| log(H/He) | ||||
| log(C/He) | ||||
| log(Ca/He) | ||||
| log(Ca/H) | ||||
| Parallax | [mas] | 0.40 (0.06) | 0.32 (0.04) | |
| Distance | [pc] | 2505.64 (352) | 3081.66 (404) | |
| Composition | ||||
| Proper motion (right ascension) | [mas/yr] | 1.279 (0.07) | 1.277 (0.03) | |
| Proper motion (declination) | [mas/yr] | -7.962 (0.1) | -7.976 (0.04) | |
| Variability | ||||
| Magnetic | ||||
| Bd | [MG] | |||
| Infrared excess (disk) | ||||
| Binarity | ||||
| B magnitude | ||||
| V magnitude | ||||
| R magnitude | ||||
| I magnitude | ||||
| J magnitude | 16.82 (0.1) | 16.82 (0.1) | ||
| H magnitude | 17.62 | |||
| K magnitude | 15.75 | |||
| u magnitude | 16.30 (0.006) | 16.30 (0.006) | ||
| g magnitude | 16.32 (0.004) | 16.32 (0.004) | ||
| r magnitude | 16.66 (0.004) | 16.66 (0.004) | ||
| i magnitude | 16.91 (0.005) | 16.91 (0.005) | ||
| z magnitude | 17.17 (0.01) | 17.17 (0.01) | ||
| G magnitude | 16.53 (0.001) | 16.50 (0.003) | ||
| BP magnitude | 16.41 (0.007) | |||
| RP magnitude | 16.61 (0.005) | |||
| Pan g magnitude | 16.41 (0.005) | |||
| Pan r magnitude | 16.69 (0.003) | |||
| Pan i magnitude | 16.96 (0.004) | |||
| Pan z magnitude | 17.16 (0.006) | |||
| Pan y magnitude | 17.27 (0.02) | |||
| E(B-V) | 0.089 | |||
* Constant surface field
Spectra without link are available upon request
The Montreal White Dwarf Database is produced and maintained by Prof. Patrick Dufour (Université de Montréal) and Dr. Simon Blouin (University of Victoria). Please send database updates, corrections, suggestions or bug reports to patrick.dufour@umontreal.ca.