Tootfinder

Using Exponential Histograms to Approximate the Quantiles of Heavy- and Light-Tailed Data
Philip T. Labo
https://arxiv.org/abs/2404.18024 https://

Using Exponential Histograms to Approximate the Quantiles of Heavy- and Light-Tailed Data
Exponential histograms, with bins of the form $\left\{ \left(ρ^{k-1},ρ^{k}\right]\right\} _{k\in\mathbb{Z}}$, for $ρ>1$, straightforwardly summarize the quantiles of streaming data sets (Masson et al. 2019). While they guarantee the relative accuracy of their estimates, they appear to use only $\log n$ values to summarize $n$ inputs. We study four aspects of exponential histograms -- size, accuracy, occupancy, and largest gap size -- when inputs are i.i.d. $\mathrm{Exp}\left(λ\right)$ or i.…

Multiple Patchy Cloud Layers in the Planetary Mass Object SIMP0136 0933
Allison M. McCarthy, Philip S. Muirhead, Patrick Tamburo, Johanna M. Vos, Caroline V. Morley, Jacqueline Faherty, Daniella C. Bardalez Gagliuffi, Eric Agol, Christopher Theissen
https://arxiv.org/abs/2402.15001

Multiple Patchy Cloud Layers in the Planetary Mass Object SIMP0136+0933
Multi-wavelength photometry of brown dwarfs and planetary-mass objects provides insight into their atmospheres and cloud layers. We present near-simultaneous $J-$ and $K_s-$band multi-wavelength observations of the highly variable T2.5 planetary-mass object, SIMP J013656.5+093347. We reanalyze observations acquired over a single night in 2015 using a recently developed data reduction pipeline. For the first time, we detect a phase shift between $J-$ and $K_s-$band light curves, which we measure…

Autonomous microARPES
Steinn Ymir Agustsson, Alfred J. H. Jones, Davide Curcio, S{\o}ren Ulstrup, Jill Miwa, Davide Mottin, Panagiotis Karras, Philip Hofmann
https://arxiv.org/abs/2403.13815

Autonomous microARPES
Angle-resolved photoemission spectroscopy (ARPES) is a technique used to map the occupied electronic structure of solids. Recent progress in X-ray focusing optics has led to the development of ARPES into a microscopic tool, permitting the electronic structure to be spatially mapped across the surface of a sample. This comes at the expense of a time-consuming scanning process to cover not only a three-dimensional energy-momentum ($E, k_z, k_y$) space but also the two-dimensional surface area. He…

Initial results of our spectro-photometric monitoring of XZ Tau
Arpan Ghosh, Saurabh Sharma, Joe Philip Ninan, Devendra K. Ojha, Aayushi Verma, Tarak Chand Sahu, Rakesh Pandey, Koshvendra Singh
https://arxiv.org/abs/2404.09361

Initial results of our spectro-photometric monitoring of XZ Tau
We present here initial results of our spectro-photometric monitoring of XZ Tau. During our monitoring period, XZ Tau exhibited several episodes of brightness variations in timescales of months at optical wavelengths in contrast to the mid-infrared wavelengths. The color evolution of XZ Tau during this period suggest that the brightness variations are driven by changes in accretion from the disc. The mid-infrared light curve shows an overall decline in brightness by $\sim$ 0.5 and 0.7 magnitude…

LoVoCCS -- II. Weak Lensing Mass Distributions, Red-Sequence Galaxy Distributions, and Their Alignment with the Brightest Cluster Galaxy in 58 Nearby X-ray-Luminous Galaxy Clusters
Shenming Fu, Ian Dell'Antonio, Zacharias Escalante, Jessica Nelson, Anthony Englert, S{\o}ren Helhoski, Rahul Shinde, Julia Brockland, Philip LaDuca, Christelyn Larkin, Lucca Paris, Shane Weiner, William K. Black, Ranga-Ram Chary, Douglas Clowe, M. C. Cooper, Megan Donahue, August Evrard, Mark Lacy, Tod …

LoVoCCS -- II. Weak Lensing Mass Distributions, Red-Sequence Galaxy Distributions, and Their Alignment with the Brightest Cluster Galaxy in 58 Nearby X-ray-Luminous Galaxy Clusters
The Local Volume Complete Cluster Survey (LoVoCCS) is an on-going program to observe nearly a hundred low-redshift X-ray-luminous galaxy clusters (redshifts $0.0310^{44}$ erg/s) with the Dark Energy Camera (DECam), capturing data in $u,g,r,i,z$ bands with a $5σ$ point source depth of approximately 25-26th AB magnitudes. Here, we map the aperture masses in 58 galaxy cluster fields using weak gravitational lensing. These clusters…

Omnidirectional gradient force optical trapping in dielectric nanocavities by inverse design
Be\~nat Martinez de Aguirre Jokisch, Benjamin Falkenberg G{\o}tzsche, Philip Tr{\o}st Kristensen, Martijn Wubs, Ole Sigmund, Rasmus Elleb{\ae}k Christiansen
https://arxiv.org/abs/2404.15102

Omnidirectional gradient force optical trapping in dielectric nanocavities by inverse design
Optical trapping enables precise control of individual particles of different sizes, such as atoms, molecules, or nanospheres. Optical tweezers provide free-space omnidirectional optical trapping of objects in laboratories around the world. As an alternative to standard macroscopic setups based on lenses, which are inherently bound by the diffraction limit, plasmonic and photonic nanostructures promise trapping by near-field optical effects on the extreme nanoscale. However, the practical desig…

Initial results of our spectro-photometric monitoring of XZ Tau
Arpan Ghosh, Saurabh Sharma, Joe Philip Ninan, Devendra K. Ojha, Aayushi Verma, Tarak Chand Sahu, Rakesh Pandey, Koshvendra Singh
https://arxiv.org/abs/2404.09361

Initial results of our spectro-photometric monitoring of XZ Tau
We present here initial results of our spectro-photometric monitoring of XZ Tau. During our monitoring period, XZ Tau exhibited several episodes of brightness variations in timescales of months at optical wavelengths in contrast to the mid-infrared wavelengths. The color evolution of XZ Tau during this period suggest that the brightness variations are driven by changes in accretion from the disc. The mid-infrared light curve shows an overall decline in brightness by $\sim$ 0.5 and 0.7 magnitude…

A first passage model of intravitreal drug delivery and residence time, in relation to ocular geometry, individual variability, and injection location
Patricia Lamirande, Eamonn A. Gaffney, Michael Gertz, Philip K. Maini, Jessica R. Crawshaw, Antonello Caruso
https://arxiv.org/abs/2404.04086…

A first passage model of intravitreal drug delivery and residence time, in relation to ocular geometry, individual variability, and injection location
Purpose: Standard of care for various retinal diseases involves recurrent intravitreal injections. This motivates mathematical modelling efforts to identify influential factors for drug residence time, aiming to minimise administration frequency. We sought to describe the vitreal diffusion of therapeutics in nonclinical species used during drug development assessments. In human eyes, we investigated the impact of variability in vitreous cavity size and eccentricity, and in injection location, o…

Hybrid data assimilation techniques using the adjoint method in a coupled Lorenz system
Philip David Kennedy, Abhirup Banerjee, Armin K\"ohl, Detlef Stammer
https://arxiv.org/abs/2403.03166

Hybrid data assimilation techniques using the adjoint method in a coupled Lorenz system
A hybrid 4D-variational data assimilation method for numerical climate models is introduced using the Lorenz '63 model. This new approach has the potential to optimise a high complexity Earth system model (ESM) by utilising the adjoint equations of an intermediate complexity ESM. The method is conceptually demonstrated by consecutively synchronising two Lorenz '63 systems to observations before optimisation. The first represents a 'high complexity' model and the second an 'intermediate complexi…

On the speed of propagation in Turing patterns for reaction-diffusion systems
V\'aclav Klika, Eamonn A. Gaffney, Philip K. Maini
https://arxiv.org/abs/2403.09247

On the speed of propagation in Turing patterns for reaction-diffusion systems
This study investigates transient wave dynamics in Turing pattern formation, focusing on waves emerging from localised disturbances. While the traditional focus of diffusion-driven instability has primarily centred on stationary solutions, considerable attention has also been directed towards understanding spatio-temporal behaviours, particularly the propagation of patterning from localised disturbances. We analyse these waves of patterning using both the well-established marginal stability cri…

Size-Mass Relations for Simulated Low-Mass Galaxies: Mock Imaging versus Intrinsic Properties
Courtney Klein, James S. Bullock, Jorge Moreno, Francisco J. Mercado, Philip F. Hopkins, Rachel K. Cochrane, Jose A. Benavides
https://arxiv.org/abs/2404.02373

Size-Mass Relations for Simulated Low-Mass Galaxies: Mock Imaging versus Intrinsic Properties
The observationally-inferred size versus stellar-mass relationship for low-mass galaxies provides an important test for galaxy formation models. However, the relationship relies on assumptions that relate observed luminosity profiles to underlying stellar mass profiles. We use the Feedback in Realistic Environments (FIRE-2) simulations of low-mass galaxies to explore how the predicted size-mass relation (SMR) changes depending on whether one uses star-particle counts directly or mock observatio…

A glance at evolvability: a theoretical analysis of its role in the evolutionary dynamics of cell populations
Juan Jim\'enez-S\'anchezMathematical Oncology Laboratory, University of Castilla-La Mancha, Ciudad Real, Spain, Carmen Ortega-SabaterMathematical Oncology Laboratory, University of Castilla-La Mancha, Ciudad Real, Spain, Philip K. MainiWolfson Centre for Mathematical Biology, Mathematical Institute, University of Oxford, Oxford, United Kingdom, V\'ictor M. P\'er…

A glance at evolvability: a theoretical analysis of its role in the evolutionary dynamics of cell populations
Evolvability is defined as the ability of a population to generate heritable variation to facilitate its adaptation to new environments or selection pressures. In this article, we consider evolvability as a phenotypic trait subject to evolution and discuss its implications in the adaptation of cell populations. We explore the evolutionary dynamics of an actively proliferating population of cells subject to changes in their proliferative potential and their evolvability using a stochastic indivi…

EC 19529-4430: SALT identifies the most carbon- and metal-poor extreme helium star
Simon Jeffery, Laura Scott, Asish Philip Monai, Brent Miszalski, Vincent Woolf
https://arxiv.org/abs/2404.03972

EC 19529-4430: SALT identifies the most carbon- and metal-poor extreme helium star
EC 19529-4430 was identified as a helium-rich star in the Edinburgh-Cape Survey of faint-blue objects and subsequently resolved as a metal-poor extreme helium (EHe) star in the SALT survey of chemically-peculiar hot subdwarfs. This paper presents a fine analysis of the SALT high-resolution spectrum. EC 19529-4430 has $T_{\rm eff} = 20\,700 \pm250$\,K, $\log g /{\rm cm\,s^{-2}} = 3.49\pm0.03$, and an overall metallicity some 1.3 dex below solar; surface hydrogen is $\approx 0.5\%$ by number. The…

Investigation of nanophotonic lithium niobate waveguides for on-chip evanescent wave sensing
Nathan A. Harper, Emily Y. Hwang, Philip A. Kocheril, Scott K. Cushing
https://arxiv.org/abs/2403.04174

Investigation of nanophotonic lithium niobate waveguides for on-chip evanescent wave sensing
Thin-film lithium niobate is a promising photonic platform that could allow for light generation, manipulation, and sample interaction all within the same compact device. Integrated sample interaction geometries for on-chip sensors have not yet been well explored in lithium niobate. We use a model thin-film lithium niobate rib waveguide excited with a 406 nm laser diode to spatially resolve the scattering and fluorescence distributions from a 60 nm dye-doped polymer film. We determine that both…