High-Resolution Infrared Spectroscopy of the Brown Dwarf Indi Ba
Bibliographic record
Abstract
We report on the analysis of high-resolution infrared spectra of the newly discovered brown dwarf Ind Ba. This is the closest known brown dwarf to the solar system, with a distance of 3.626 pc. Spectra covering the ranges of λλ2.308-2.317 μm and λλ1.553-1.559 μm were observed at a resolution of λ/Δλ = R = 50,000. The physical parameters of effective temperature and surface gravity are derived for Ind Ba by comparison with model spectra calculated from atmospheres computed using unified cloudy models. The results are T eff = 1500 ± 100 K, log g = 5.2 ± 0.3 (in units of cm s -2 ), placing it in the critical boundary between the late L and early T dwarfs. The high spectral resolution also allows us to measure an accurate projected rotational velocity, with v sin i = 28 ± 3 km s -1 . Combined with a published luminosity for Ind Ba [with log( L / L ☉ ) = -4.71], the derived parameters result in a "spectroscopic" mass estimate of ~30 M J , a radius of ~0.062 R ☉ , and a maximum rotational period of ~3.0 hr. A compilation and comparison of effective temperatures derived from spectroscopy using model atmospheres versus those derived from luminosities and theoretical M bol -radius relations reveal a systematic disagreement in the T eff scale. The source of this disagreement is unknown.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".