Tootfinder

Exploring the role of accretion disk geometry in shaping black hole shadows
Zi-Liang Wang
https://arxiv.org/abs/2506.21148 https://ar…

Exploring the role of accretion disk geometry in shaping black hole shadows
We study black hole imaging in the context of geometrically thick accretion disks in Schwarzschild spacetime. By decomposing the emitting region into a set of one-dimensional luminous segments, each characterized by its inclination angle and inner radius, we construct transfer functions that capture key image features-namely, the direct image, lensing ring, and photon ring. This approach allows a unified treatment of disk geometry and viewing angle. We explore three regimes: optically thin, opt…

Still rocking this for my #WristCheck. I actually really like this one.
On the one hand there is a lot going on on that dial bit it remains readable and everything present serves a purpose. No extraneous text* or logos, so while it is busy, it's also clean.
* Ok, ok maybe the tiny "JAPAN MOVT" at the bottom is pointless but it's so small it's almost not r…

Quick tip for those with young kids who want them to learn how to use a watch with an analogue (dial) style interface.
While the likes of Flik Flak make nice kids watches, they are a little on the pricy side.
Potentially better IMHO however are these kids field/pilot style watches from AliExpress. They cost basically nothing [<$5🇺🇸] and the hour hand points to an inner ring of numbered hours, while the minute hand points to an outer ring of numbered minutes. So simple!

Solitonic Andreev Spin Qubit
Pablo San-Jose, Elsa Prada
https://arxiv.org/abs/2506.15502 https://arxiv.org/pdf/2506.15502

Solitonic Andreev Spin Qubit
We propose a novel type of superconducting spin qubit, dubbed solitonic Andreev spin qubit (SASQ), that combines features of Andreev spin qubits and geometric spin qubits. The two SASQ states are the degenerate spin orientations of an Andreev bound state trapped in a circular Josephson junction with a Corbino disk geometry, created on a 2DEG. The junction is subjected to a weak magnetic flux that induces a fluxoid mismatch between the inner disk and outer ring superconductors. The fluxoid misma…

Constraints on Quaoar's rings and atmosphere from JWST/NIRCam observations of a stellar occultation
Benjamin Proudfoot, Bryan Holler, Ko Arimatsu, Flavia Rommel, Cameron Collyer, Estela Fern\'andez-Valenzuela
https://arxiv.org/abs/2506.07898

Constraints on Quaoar's rings and atmosphere from JWST/NIRCam observations of a stellar occultation
Observations of stellar occultations have revealed that small bodies are capable of hosting ring systems. The trans-Neptunian object (TNO) Quaoar, is the host of an enigmatic ring system, with two rings located well-outside the Roche limit. To better understand these structures, we observed a stellar occultation by Quaoar and its rings using the James Webb Space Telescope's (JWST) NIRCam instrument. Our observations detect both known rings, although Q2R -- the inner known ring -- is not detecte…