Tootfinder

Vz-GAL Dusty Star-Forming Galaxies: Revisiting the CO-H2 Conversion Factor Tension
Prachi Prajapati, Axel Weiss, Dominik Riechers, Tom J. L. C. Bakx, Leindert A. Boogaard, Diana Ismail, Pierre Cox, Andrew J. Baker, Roberto Neri, Matthew Lehnert, Chentao Yang, Emilio Romano-Diaz, Hiddo S. B. Algera, Stefano Berta, Edoardo Borsato, Kirsty M. Butler, Asantha Cooray, Bethany Jones, Amelie Saintonge, Paul van der Werf
https://arxiv.org/abs/2607.18440 https://arxiv.org/pdf/2607.18440 https://arxiv.org/html/2607.18440
arXiv:2607.18440v1 Announce Type: new
Abstract: The CO luminosity-to-H$_2$ mass conversion factor ($\alpha_{CO}$) remains a debated uncertainty in determining molecular gas masses of high-redshift dusty star-forming galaxies (DSFGs). Dynamical mass constraints have often favored $\alpha_{CO}=0.8$~$M_{\odot}~{(K~km~{s}^{-1}~{pc}^{2})}^{-1}$, whereas dust- and radiative-transfer-based methods imply higher values. We revisit this ``tension" using the largest homogeneous sample of 21 unlensed $z\sim1-4$ DSFGs, with securely measured \coonezero luminosities from the VLA \vzgal survey and resolved ($\sim{0.1}^{\prime\prime}$) ALMA 1~mm dust continuum imaging. For 12 galaxies with robust modeling constraints, we derive molecular gas masses using dust spectral energy distribution modeling and the TUNER LVG framework, adopting a solar-metallicity gas-to-dust mass ratio of 100. Although not fully independent due to shared assumptions on dust properties, these approaches yield mutually consistent gas masses corresponding to $\alpha_{CO}\sim1.5-11.5$, with a median near the Galactic $\alpha_{CO}=4.3$. Isotropic virial dynamical masses agree with these gas masses when realistic molecular gas sizes are adopted, while our proposed ``mixed" (rotating, pressure-supported, thick-disk) estimator systematically underestimates dynamical masses, producing low $\alpha_{CO}$ limits. Using GN20 ($z=4.055$) as a case study, we show that resolved gas geometry and kinematics reconcile the discrepancy with LVG-derived $\alpha_{CO}$. Our results suggest that current data do not require $\alpha_{CO}=0.8$, and intermediate to near-Galactic values remain dynamically viable given uncertainties in gas geometry, dust properties, and gas-to-dust ratios. Further progress in calibrating $\alpha_{CO}$ in the early universe will require resolved molecular gas observations, physically motivated ISM modeling, and stringent constraints on dust properties.
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Since when did autumn become dangerous?
Anyway, one of a myriad reasons I don’t log into LinkedIn (except, apparently, to self-promote, which is the whole reason it exists).

RE: https://mastodon.social/@mcfadden/116590848112694824
I’ll throw a “strong agree” behind this one. Give us:
⁃ scholars
⁃ writers, musicians, artists
⁃ scientists
⁃ people whose own thoughts, creativity, and hard work have made something that makes the world better (and no, this does not include CEOs)

Magic Moment (when the view finally opens up)
(On the way to Drachensee, October 2023)
#SilentSunday #LandscapePhotography #Alps

Avex Music Group plans a $100M fund to acquire music copyrights, companies, and publishing catalogs over the next 12 months (Elizabeth Dilts Marshall/Billboard)
https://www.billboard.com/pro/avex-music-group-launches-100-million-catalog-fund/

Avex Music Group Launches $100 Million Publishing Catalog Fund
Avex Music Group announced the launch of a $100 Million publishing catalog fund and acquired the catalog of Teddy Swims collaborator Infamous.

A Splitting Architecture for Exact Reduced Coulomb Friction
Hongcheng Song, Ye Fan, Uri M. Ascher, Dinesh K. Pai
https://arxiv.org/abs/2607.19599 https://arxiv.org/pdf/2607.19599 https://arxiv.org/html/2607.19599
arXiv:2607.19599v1 Announce Type: new
Abstract: Existing approaches to frictional contact dynamics typically either modify the Coulomb law to improve numerical robustness or solve the exact law in a fully coupled monolithic form. However, in its reduced form, exact Coulomb friction can be written as a cone complementarity problem with an augmented velocity, which reveals a natural split between a cone-constrained linear response and a scalar non-associated coupling induced by tangential velocity. We exploit this structure in the solver design. Our method uses an outer iteration to update the non-associated coupling explicitly, and an inner solve for a strongly convex cone-constrained quadratic program. This separation also makes the inner solver modular, so different numerical schemes can be used without changing the outer iteration. We evaluate the method on rigid-body benchmarks with stick-slip transitions and frictional stacking, and show that it reproduces exact Coulomb complementarity without smoothing or relaxing the friction law.
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Swiss pharmaceutical group Roche agrees to acquire US-based PathAI, which makes AI diagnostic tools, for up to $1.05B, with $750M upfront, closing in H2 2026 (AdriŠ Calatayud/Wall Street Journal)
https://www.

🇺🇦 #NowPlaying on #BBC6Music's #NewMusicFix
Knats:
🎵 Azure Blues (6 Music Session, 19 May 2026)
#Knats
https://knats.bandcamp.com/track/azure-blues-2
https://open.spotify.com/track/21E19rcwx9hzj74iqozk9L

Sources: Sony is in talks to acquire Recognition Music Group, which includes works of Justin Bieber and Neil Young, from Blackstone for between $3.5B and $4B (Lucas Shaw/Bloomberg)
https://www.bloomberg.com/news/articles/2026-05-0…