A Virgo Environmental Survey Tracing Ionised Gas Emission (VESTIGE)
Bibliographic record
Abstract
Using the VESTIGE survey, a deep narrow-band Hαimaging survey of the Virgo cluster carried out at the CFHT with MegaCam, we discovered a long and diffuse tail of ionised gas in the edge-on late-type galaxy NGC 4330. This peculiar feature indicates an ongoing ram pressure stripping event able to remove the gas in the outer region of the disc. Tuned hydrodynamic simulations suggest that the ram pressure stripping event is occurring almost face-on, making NGC 4330 the ideal candidate for studying the effects of the perturbation in the direction perpendicular to the disc plane. We present here two new independent sets of Fabry-Perot observations (R≃ 10 000) with the purpose of understanding the effects of the ram pressure stripping process on the kinematics of the ionised gas. Despite their limited sensitivity to the diffuse gas emission, the data allowed us to measure the velocity and the velocity dispersion fields over the galaxy disc and in several features at the edges or outside the stellar disc formed after the ram pressure stripping event. We constructed the position-velocity diagrams and the rotation curves of the galaxy using three different techniques. The data show, consistent with the hydrodynamic simulations, that the galaxy has an inner solid-body rotation up to ∼2.4 kpc, with non-circular streaming motions outside this radius and in the several external features formed during the interaction of the galaxy with the surrounding intracluster medium. The data also indicate a decrease in the rotational velocity of the gas with increasing distance from the galaxy disc along the tails, suggesting a gradual but not linear loss of angular momentum in the stripped gas. Consistent with a ram pressure stripping scenario, thei-band image shows a boxy shape at the south-west edge of the disc, where the stellar orbits might have been perturbed by the modification of the gravitational potential well of the galaxy due to the displacement of the gas in thezdirection.
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 | 0.002 | 0.002 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.003 | 0.001 |
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".