Results 21 to 30 of about 584 (255)

Estimating the Oblateness of Dark Matter Halos Using Neutral Hydrogen Velocity Dispersion

The Astrophysical Journal Letters, 2023
We derive the oblateness parameter q of the dark matter halo of a sample of gas-rich, face-on disk galaxies. We have assumed that the halos are triaxial in shape but their axes in the disk plane ( a and b ) are equal, so that q = c / a measures the halo ...
Mousumi Das, Roger Ianjamasimanana, Stacy S. McGaugh, James Schombert, K. S. Dwarakanath   +4 more
doaj   +1 more source

Oblation [PDF]

Elements of this book, Oblation: Essays, Parables, Paradoxes, defy reason. They do so for good reason. Much of what we do, much of what we think, is oblation: sacrifice, offering, to something or someone. The root of “oblation” is “to draw near” or “to dwell in.” It refers to what is brought unto the altar, literal or proverbial — the profoundest ...
openaire   +5 more sources

SunSketcher: a Citizen Science network project for the heliophysics big year

Frontiers in Astronomy and Space Sciences
SunSketcher is an innovative program of eclipse observations that utilizes a network of smartphones along the path of totality to identify and geolocate the precise contact times via their definitive signature–Baily’s Beads–and hence place meaningful ...
A. Gordon Emslie, Hugh S. Hudson, Hugh S. Hudson, Hugh S. Hudson, Greg Arbuckle, J. Michael Galloway, Travis Peden, Starr May, Tameka Ferguson, Kelly Miller, Tabitha Cline, Shikha Sawant, Andrea Florence, Kelcee Gabbard, Janessa Unseld, Leah Spalding, Mark Simpson, Ernest T. Wright   +17 more
doaj   +1 more source

Optimizing photoexcitation conditions for time‐resolved X‐ray solution scattering experiments

FEBS Open Bio, EarlyView.
Time‐resolved X‐ray solution scattering (TR‐XSS) is a powerful technique to visualize how proteins change their structure in real time after light activation. Selecting the right laser photoexcitation conditions—fluence, excitation geometry, and sample refresh rate—is critical to maximize the experimental signal while avoiding unwanted side effects ...
Matteo Levantino
wiley   +1 more source

Detecting Planetary Oblateness in the Era of JWST: A Case Study of Kepler-167e

The Astronomical Journal
Planets may be rotationally flattened, and their oblateness thus provides useful information on their formation and evolution. Here, we develop a new algorithm that can compute the transit light curve due to an oblate planet very efficiently and use it ...
Quanyi Liu, Wei Zhu, Yifan Zhou, Zhecheng Hu, Zitao Lin, Fei Dai, Kento Masuda, Sharon X. Wang   +7 more
doaj   +1 more source

Oblate Skyrmions [PDF]

Physical Review D, 1998
The spherically symmetric hedgehog ansatz used in the description of the skyrmion is believed to be inadequate for the rotational states such as the nucleon (I=J=1/2) and the Delta (I=J=3/2) due to centrifugal forces. We study here a simple alternative: an oblate spheroidal solution which leads to lower masses for these baryons.
Leblond, F., Marleau, L.
openaire   +2 more sources

A Numerical–Experimental Approach for Multi‐Matrix Fiber‐Reinforced Plastics Characterization Using Finite Element Model Updating

Advanced Engineering Materials, EarlyView.
A numerical–experimental framework is developed for characterizing multi‐matrix fiber‐reinforced polymers (MM‐FRPs) combining epoxy and polyurethane matrices. Harmonic bending tests are integrated with finite element model updating (FEMU) to simultaneously identify elastic and viscoelastic material parameters.
Rodrigo M. Dartora, Tales V. Lisbôa, Axel Spickenheuer, Rogério J. Marczak, Jakson M. Vassoler   +4 more
wiley   +1 more source

Slow Rotation for the Super-puff Planet Kepler-51d

The Astrophysical Journal Letters
Super-puffs are low-density planets of unknown origin and composition. If they form by accreting nebular gas through a circumplanetary disk, one might expect super-puffs to be spinning quickly. Here, we derive upper limits on the rotational oblateness of
Caleb Lammers, Joshua N. Winn
doaj   +1 more source

Luminosity variation in the extended one-zone RR Lyrae model [PDF]

Serbian Astronomical Journal, 2005
The Stellingwerf one-zone stellar model is extended by assuming, a slow and uniform rotation that leads to a very small oblateness of the star. The matter in the core-surrounding shell is supposed to consists of a mixture of ideal gas and radiation. This
Pricopi D.
doaj   +1 more source

Phase Field Failure Modeling: Brittle‐Ductile Dual‐Phase Microstructures under Compressive Loading

Advanced Engineering Materials, EarlyView.
The approach by Amor and the approach by Miehe and Zhang for asymmetric damage behavior in the phase field method for fracture are compared regarding their fitness for microcrack‐based failure modeling. The comparison is performed for the case of a dual‐phase microstructure with a brittle and a ductile constituent.
Jakob Huber, Jan Torgersen, Ewald Werner
wiley   +1 more source