Although the abstract makes something of a song and dance about how the HI is aligned with filaments in the cosmic web, and even the title of the paper mentions this, in fact there's very little about this in the paper at all. And since they only have ten galaxies, I'm going to entirely discard their "main" result here.
In fairness, the authors say themselves, "any of the relations shown should be considered only a hint of a trend at most". This is very much a preliminary paper, but it does show some interesting possibilities for the future. Although they only have ten galaxies, they've also (don't ask me how) determined the large-scale structure of many other galaxies, i.e. the 3D geometry of the cosmic web. That means they can plot the properties of their sample as a function of true filamentary distance. Normally everyone uses projected distance, which assumes that any two objects are at the same distance from us and then just measures their distance across the sky as a proxy for their separation. Using true distance is obviously better, although just how accurate this I'm not at all sure.
But let's assume that it's fine. What do they find ?
Quite a few things. But not as much as they might, because they select their sample not only by HI detection but also Halpha (which traces star formation activity). So although they potentially had 33 galaxies to study, they limit themselves to 10. It would have been nice to use the rest for the HI-only trends, but oh well.
Anyway, even though they're only sensitive to dense gas, most galaxies in their sample show lopsidedness. They also have weird-looking spectra, including one with a triple peak instead of the usual double-horn (Batman-shaped) profile. They don't comment too much on this, though they may be signatures of interactions.
More interesting are the possible large-scale trends. There doesn't appear to be any relation at all between stellar mass and gas loss, but it looks to me that galaxies closer to the filament have lost less gas and may even be gas-rich. The authors disagree though, saying there's no trend, and admittedly this appearance is dominated by a single, weirdly gas-rich galaxy. It's still odd if you ask me.
On the other hand, HI mass quite clearly decreases with distance to the filament. Absolute mass is a tricky quantity, mind, and it probably would have been a good idea to also plot stellar mass. There seems to be hint that specific star formation rate (that's s.f.r. per unit mass, useful to correct for the fact that bigger galaxies tend to have more gas to form stars simply just because big things are bigger) increases closer to the filaments. Gas fraction shows no evidence of any trends at all.
This is a nice way to illustrate how difficult it is to interpret the results. Other studies have variously found evidence of gas depletion or enhancement within filaments. It may also depend on whether you look at the gas fraction of individual galaxies as opposed to the fraction of galaxies which have gas detections at all. If instead you plot distance not from filament but from nearest neighbour, things get different again, with the trends changing considerably (they say they are no obvious relations at all - I'm not sure about that, but with ten galaxies... well...).
Finally, they note that galaxies tend to have a constant gas density, which agrees well with previous claims. There's no obvious trend in any deviation from the Tully-Fisher relation either, although one interesting object does look at though it might be rotating too slowly.
This is all very inconclusive. It does demonstrate the potential of the full survey quite well, but I would have liked it more if they'd used their full HI sample where possible. It's a nice enough analysis, but the final result is very definitely "watch this space".
CHILES VI: HI and H${\alpha}$ Observations for z < 0.1 Galaxies; Probing HI Spin Alignment with Filaments in the Cosmic Web
We present neutral hydrogen (HI) and ionized hydrogen (H${\alpha}$) observations of ten galaxies out to a redshift of 0.1. The HI observations are from the first epoch (178 hours) of the COSMOS HI Large Extragalactic Survey (CHILES). Our sample is HI biased and consists of ten late-type galaxies with HI masses that range from $1.8\times10^{7}$ M$_{\odot}$ to $1.1\times10^{10}$ M$_{\odot}$.
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