Tootfinder

Dynamics of helical vortex filaments in non viscous incompressible flows
Martin DonatiUMPA-ENSL, Christophe LacaveLAMA, Evelyne MiotIF, Mathdoc
https://arxiv.org/abs/2403.00389

Dynamics of helical vortex filaments in non viscous incompressible flows
In this paper we study concentrated solutions of the three-dimensional Euler equations in helical symmetry without swirl. We prove that any helical vorticity solution initially concentrated around helices of pairwise distinct radii remains concentrated close to filaments. As suggested by the vortex filament conjecture, we prove that those filaments are translating and rotating helices. Similarly to what is obtained in other frameworks, the localization is weak in the direction of the movement b…

Slender vortex filaments in the Boussinesq Approximation
Marie Rodal, Daniel Margerit, Rupert Klein
https://arxiv.org/abs/2403.00460 https://

Slender vortex filaments in the Boussinesq Approximation
A model for the motion of slender vortex filaments is extended to include the effect of gravity. The model, initially introduced by Callegari and Ting (SIAM, J. of App. Math., (1978), vol. 35, pp. 148-175), is based on a matched asymptotic expansion in which the outer solution, given by the Biot-Savart law, is matched with the inner solution derived from the Navier-Stokes equations. Building on recent work by Harikrishnan et al (Phys. of Fluids, (2023), vol. 35) the Boussinesq approximation is …

Optimization of cosmic filament finders and unbiased recovery of filament phase space profiles using mock filaments
Saee DhawalikarIUCAA, Aseem ParanjapeIUCAA
https://arxiv.org/abs/2402.18669

Optimization of cosmic filament finders and unbiased recovery of filament phase space profiles using mock filaments
Cosmic filaments, the most prominent features of the cosmic web, possibly hold untapped potential for cosmological inference. While it is natural to expect the structure of filaments to show universality similar to that seen in dark matter halos, the lack of agreement between different filament finders on what constitutes a filament has hampered progress on this topic. We initiate a programme to systematically investigate and uncover possible universal features in the phase space structure of c…

Energy deposition in air by moderately focused femtosecond laser filaments
Yu. E. Geints, I. Yu. Geints, Ya. V. Grudzin, A. V. Koribut, D. V. Pushkarev, G. E. Rizaev, L. V. Seleznev
https://arxiv.org/abs/2403.00242

Energy deposition in air by moderately focused femtosecond laser filaments
Filamentation of high-power femtosecond laser pulses in air is accompanied by a fairly strong release of optical energy into the propagation medium due to laser-induced ionization of air molecules and production of an underdense plasma of charged species. We present the results of our laboratory experiments and numerical simulations aimed to the estimation of energy deposition amount by laser filament upon propagation in air depending on the conditions of spatial focusing, pulse energy, and rad…

Magnetic filaments: formation, stability, and feedback
Evgeny A. Kuznetsov, Evgeny A. Mikhailov
https://arxiv.org/abs/2402.16989 https://

Magnetic filaments: formation, stability, and feedback
As well known, magnetic fields in space are distributed very inhomogeneously. Some-times field distributions have forms of filaments with high magnetic field values. As many ob-servations show, such a filamentation takes place in convective cells in the Sun and other astro-physical objects. This effect is associated with the frozenness of the magnetic field into a medium with high conductivity that leads to compression of magnetic field lines and forming magnetic filaments. We show analytically…

This https://arxiv.org/abs/2404.09098 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

A Millisecond Pulsar Binary Embedded in a Galactic Center Radio Filament
The Galactic Center is host to a population of extraordinary radio filaments, thin linear structures that trace out magnetic field lines running perpendicular to the Galactic plane. Using Murriyang, the 64 m Parkes radio telescope, we conducted a search for pulsars centered on the position of a compact source in the filament G359.0$-$0.2. We discovered a millisecond pulsar (MSP), PSR J1744$-$2946, with a period $P = 8.4$ ms, that is bound in a 4.8 hr circular orbit around a $M_{\rm c} > 0.05\,M…

Label-free discrimination of actin and myosin muscle networks using nonresonant contribution of Multiplex-Coherent anti-Stokes Raman Scattering (M-CARS)
Malik Nafa, Tigran Mansuryan, Vincent Couderc, Laetitia Magnol, V\'eronique Blanquet, Fabienne Baraige, Claire Carrion, Jean-Ren\'e Ducl\`ere, Claire Lefort
https://arxi…

Label-free discrimination of actin and myosin muscle networks using nonresonant contribution of Multiplex-Coherent anti-Stokes Raman Scattering (M-CARS)
We propose an original experimental strategy providing evidence for the first label-free disclosure of muscle actin network based on the nonresonant contribution of a multiplex CARS (M-CARS) microscopy setup. Thin actin filaments are known for being located between thick myosin filaments that can be detected in Second Harmonic Generation (SHG) with our M-CARS setup. The first step of our strategy consists in defining spatial regions where thick myosin filaments or thin actin filaments are expec…

Cold Filaments Formed in Hot Wake Flows Uplifted by AGN Bubbles in Galaxy Clusters
Xiaodong Duan, Fulai Guo
https://arxiv.org/abs/2403.02807 https://arxiv.org/pdf/2403.02807
arXiv:2403.02807v1 Announce Type: new
Abstract: Multi-wavelength observations indicate that the intracluster medium in some galaxy clusters contains cold filaments, while their formation mechanism remains debated. Using hydrodynamic simulations, we show that cold filaments could naturally condense out of hot gaseous wake flows uplifted by the jet-inflated active galactic nucleus (AGN) bubbles. Consistent with observations, the simulated filaments extend to tens of kpc from the cluster center, with a representative mass of $\rm 10^{8}- 10^{9}\ M_{\odot}$ for a typical AGN outburst energy of $10^{60}~ \rm erg$. They show smooth velocity gradients, stretching typically from inner inflows to outer outflows with velocity dispersions of several hundred $\rm km\ s^{-1}$. The properties of cold filaments are affected substantially by jet properties. Compared to kinetic energy-dominated jets, thermal energy-dominated jets tend to produce longer cold filaments with higher masses. With the same jet energy, AGN jets with an earlier turn-on time, a lower jet base, or a higher power heat the cluster center more effectively, and produce shorter filaments at a much later epoch.

Tracing and segmentation of molecular patterns in 3-dimensional cryo-et/em density maps through algorithmic image processing and deep learning-based techniques
Salim Sazzed
https://arxiv.org/abs/2403.17293

Tracing and segmentation of molecular patterns in 3-dimensional cryo-et/em density maps through algorithmic image processing and deep learning-based techniques
Understanding the structures of biological macromolecules is highly important as they are closely associated with cellular functionalities. Comprehending the precise organization actin filaments is crucial because they form the dynamic cytoskeleton, which offers structural support to cells and connects the cell's interior with its surroundings. However, determining the precise organization of actin filaments is challenging due to the poor quality of cryo-electron tomography (cryo-ET) images, wh…

KnotResolver: Tracking self-intersecting filaments in microscopy using directed graphs
Dhruv Khatri, Shivani A. Yadav, Chaitanya A. Athale
https://arxiv.org/abs/2404.12029

KnotResolver: Tracking self-intersecting filaments in microscopy using directed graphs
Quantification of microscopy time-series of in vitro reconstituted motor driven microtubule (MT) transport in 'gliding assays' is typically performed using computational object tracking tools. However, these are limited to non-intersecting and rod-like filaments. Here, we describe a novel computational image-analysis pipeline, KnotResolver, to track image time-series of highly curved self-intersecting looped filaments (knots) by resolving cross-overs. The code integrates filament segmentation a…

Developing an Automated Detection, Tracking and Analysis Method for Solar Filaments Observed by CHASE via Machine Learning
Z. Zheng, Q. Hao, Y. Qiu, J. Hong, C. Li, M. D. Ding
https://arxiv.org/abs/2402.14209

Developing an Automated Detection, Tracking and Analysis Method for Solar Filaments Observed by CHASE via Machine Learning
Studies on the dynamics of solar filaments have significant implications for understanding their formation, evolution, and eruption, which are of great importance for space weather warning and forecasting. The H$α$ Imaging Spectrograph (HIS) onboard the recently launched Chinese H$α$ Solar Explorer (CHASE) can provide full-disk solar H$α$ spectroscopic observations, which bring us an opportunity to systematically explore and analyze the plasma dynamics of filaments. The dramatically increase…

Relation between the local width and linear halo mass density of cosmic filaments
Weishan Zhu, Tian-Rui Wang, Fupeng Zhang, Yi Zheng, Long-Long Feng
https://arxiv.org/abs/2404.09028

Relation between the local width and linear halo mass density of cosmic filaments
Large-scale cosmic filaments may have played an important role in shaping the properties of galaxies. Meanwhile, cosmic filaments are believed to harbor a substantial portion of the missing baryons at redshift z < 2. To inspect the role of filaments in these issues, many properties of filaments need to be examined, including their lengths, thicknesses, and density profiles. However, measuring some of these properties poses challenges. This study concentrates on estimating filament width/thickne…

Magnetic Helicity Signs and Flaring Propensity: Comparing Force-free Parameter with the Helicity signs of H{\alpha} Filaments and X-ray Sigmoids
V. Aparna, Manolis K. Georgoulis, Petrus C. Martens
https://arxiv.org/abs/2403.17075

Magnetic Helicity Signs and Flaring Propensity: Comparing Force-free Parameter with the Helicity signs of Hα Filaments and X-ray Sigmoids
Sigmoids produce strong eruptive events. Earlier studies have shown that the ICME axial magnetic field Bz can be predicted with some credibility by observing the corresponding filament or the polarity inversion line in the region of eruption and deriving the magnetic field direction from that. Sigmoids are coronal structures often associated with filaments in the sigmoidal region. In this study, firstly we compare filament chirality with sigmoid handedness to observe their correlation. Secondly…

Weak-Lensing Detection of #Intracluster Filaments in the Coma Cluster: #DarkMatter Web Detected in #ComaCluster: https://subarutelescope.org/en/results/2024/02/07/3367.html

State-dependent stiffness enhances wave propagation along elastic filaments
Cl\'ement Moreau, Benjamin J. Walker, Rebecca N. Poon, Daniel Soto, Daniel I. Goldman, Eamonn A. Gaffney, Kirsty Y. Wan
https://arxiv.org/abs/2402.13844

State-dependent stiffness enhances wave propagation along elastic filaments
We study an elastic filament beating in a viscous fluid with curvature-dependent bending stiffness. Our numerical and experimental investigations reveal that such differential stiffness can sustain planar bending waves far along flexible filaments. In particular, basal actuation is a viable, parsimonious mechanism for generating high-amplitude planar bending waves, in stark contrast to the uniform-stiffness case. Further, the resulting beat patterns closely resemble the power-and-recovery strok…

Discovery of a [O III] Emission Shell Around the X-ray Binary CI Cam
Robert A. Fesen, Marcel Drechsler, Nicolas Martino, Yann Sainty
https://arxiv.org/abs/2404.18022

Discovery of a [O III] Emission Shell Around the X-ray Binary CI Cam
We report the serendipitous discovery of a $8' \times 12'$ emission shell brightest in [O III] centered on the X-ray binary B[e] star, CI Cameleopardalis (CI Cam). This shell, detected during a survey of optical emission associated with the Galactic supernova remnant G150.3+4.5, is seen outside but immediately adjacent to the remnant's optical filaments along its northwestern edge. Assuming this shell is related to CI Cam's strong winds and transient outbursts, the adoption of CI Cam's Gaia DR3…

Galaxy Triplets Alignment in Large-scale Filaments
Yu Rong, Jinzhi Shen, Zichen Hua
https://arxiv.org/abs/2403.13273 https://arxiv.or…

Galaxy Triplets Alignment in Large-scale Filaments
Leveraging the datasets of galaxy triplets and large-scale filaments obtained from the Sloan Digital Sky Survey, we scrutinize the alignment of the three sides of the triangles formed by galaxy triplets and the normal vectors of the triplet planes within observed large-scale filaments. Our statistical investigation reveals that the longest and median sides of the galaxy triplets exhibit a robust alignment with the spines of their host large-scale filaments, while the shortest sides show no or o…

The boundary of cosmic filaments
Wei Wang, Peng Wang, Hong Guo, Xi Kang, Noam I. Libeskind, Daniela Galarraga-Espinosa, Volker Springel, Rahul Kannan, Lars Hernquist, Rudiger Pakmor, Haoran Yu, Sownak Bose, Quan Guo, Luo Yu, Cesar Hernandez-Aguayo
https://arxiv.org/abs/2402.11678

The boundary of cosmic filaments
For decades, the boundary of cosmic filaments have been a subject of debate. In this work, we determine the physically-motivated radii of filaments by constructing stacked galaxy number density profiles around the filament spines. We find that the slope of the profile changes with distance to the filament spine, reaching its minimum at approximately 1 Mpc at z = 0 in both state-of-the-art hydrodynamical simulations and observational data. This can be taken as the average value of the filament r…

Undulatory swimming in suspensions and networks of flexible filaments
Adam K. Townsend, Eric E. Keaveny
https://arxiv.org/abs/2403.13009 https://

Undulatory swimming in suspensions and networks of flexible filaments
Many biological fluids are composed of suspended polymers immersed in a viscous fluid. A prime example is mucus, where the polymers are also known to form a network. While the presence of this microstructure is linked with an overall non-Newtonian response of the fluid, swimming cells and microorganisms similar in size to the network pores and polymer filaments instead experience the heterogeneous nature of the environment, interacting directly with the polymers as obstacles as they swim. To ch…

A Universal Method for Solar Filament Detection from H-alpha Observations using Semi-supervised Deep Learning
Andrea Diercke, Robert Jarolim, Christoph Kuckein, Sergio J. Gonz\'alez Manrique, Marco Ziener, Astrid M. Veronig, Carsten Denker, Werner P\"otzi, Tatiana Podladchikova, Alexei A. Pevtsov
https://arxiv.org/abs/2…

A Universal Method for Solar Filament Detection from H-alpha Observations using Semi-supervised Deep Learning
Filaments are omnipresent features in the solar atmosphere. Their location, properties and time evolution can provide information about changes in solar activity and assist the operational space weather forecast. Therefore, filaments have to be identified in full disk images and their properties extracted from these images. Manual extraction is tedious and takes much time; extraction with morphological image processing tools produces a large number of false-positive detections. Automatic object…

B-fields And dust in interstelLar fiLAments using Dust POLarization (BALLAD-POL): II. Testing the Radiative Torque Paradigm in Musca and OMC-1
Nguyen Bich Ngoc, Thiem Hoang, Pham Ngoc Diep, Le Ngoc Tram
https://arxiv.org/abs/2403.16857

B-fields And dust in interstelLar fiLAments using Dust POLarization (BALLAD-POL): II. Testing the Radiative Torque Paradigm in Musca and OMC-1
Polarization of starlight and thermal dust emission caused by aligned dust grains is a valuable tool to characterize magnetic fields (B-fields) and constrain dust properties. However, the physics of grain alignment is not fully understood. To test the popular paradigm of radiative torque (RAT) theory, including RAT alignment (RAT-A) and disruption (RAT-D), we use dust polarization data observed by {\it Planck} and SOFIA/HAWC+ toward two filaments with contrasting physical conditions: Musca, a q…

This https://arxiv.org/abs/2308.06592 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

On an angle-averaged Neumann-to-Dirichlet map for thin filaments
We consider the Laplace equation in the exterior of a thin filament in $\mathbb{R}^3$ and perform a detailed decomposition of a notion of slender body Neumann-to-Dirichlet (NtD) and Dirichlet-to-Neumann (DtN) maps along the filament surface. The decomposition is motivated by a filament evolution equation in Stokes flow for which the Laplace setting serves as an important toy problem. Given a general curved, closed filament with constant radius $ε>0$, we show that both the slender body DtN and …

Proper motion of Cygnus loop shock filaments
M. Vucetic, N. Milanovic, D. Urosevis, J. Raymond, D. Onic, S. Milosevic, N. Petrov
https://arxiv.org/abs/2403.05215

Proper motion of Cygnus loop shock filaments
We determined shock speed in the Galactic supernova remnant Cygnus Loop, using proper motion of its optical filaments and the latest estimate for its distance. The proper motion was measured by comparing H$α$ images of the remnant observed in two epochs: 1993 (Kitt Peak National Observatory) and 2018/2019 (National Astronomical Observatory Rozhen and Astronomical station Vidojevica). We derived shock speed for 35 locations along different filaments, which is twice as much as in earlier studies…

N$_2$H$^ $(1-0) as a tracer of dense gas in and between spiral arms
O. Feher, S. E. Ragan, F. D. Priestley, P. C. Clark, T. J. T. Moore
https://arxiv.org/abs/2403.19269

N$_2$H$^+$(1-0) as a tracer of dense gas in and between spiral arms
Recent advances in identifying giant molecular filaments in galactic surveys allow us to study the interstellar material and its dense, potentially star forming phase on scales comparable to resolved extragalactic clouds. Two large filaments detected in the CHIMPS $^{13}$CO(3-2) survey, one in the Sagittarius-arm and one in an inter-arm region, were mapped with dense gas tracers inside a 0.06 deg$^2$ area and with a spatial resolution of around 0.4 and 0.65 pc at the distance of the targets usi…

Dissecting a miniature universe: A multi-wavelength view of galaxy quenching in the Shapley supercluster
N. Aghanim, T. Tuominen, V. Bonjean, C. Gouin, T. Bonnaire, M. Einasto
https://arxiv.org/abs/2402.18455

Dissecting a miniature universe: A multi-wavelength view of galaxy quenching in the Shapley supercluster
Multiple-cluster systems, superclusters, contain large numbers of galaxies assembled in clusters inter-connected by multi-scale filamentary networks. As such, superclusters are a smaller version of the cosmic web and can be considered as miniature universes. Superclusters also contain gas, hot in the clusters and warmer in the filaments. Thus, they are ideal laboratories to study the interplay between the galaxies and the gas. In this context, the Shapley supercluster (SSC) stands out since it …

This https://arxiv.org/abs/2309.11344 has been replaced.
initial toot: https://mastoxiv.page/@arXi…

Energetics of twisted elastic filament pairs
We investigate the elastic energy stored in a filament pair as a function of applied twist by measuring torque under prescribed end-to-end separation conditions. We show that the torque increases rapidly to a peak with applied twist when the filaments are initially separate, then decreases to a minimum as the filaments cross and come into contact. The torque then increases again while the filaments form a double helix with increasing twist. A nonlinear elasto-geometric model that combines the e…

Formation of Polar Crown Filaments Magnetic Fields by Supergranular Helicity Injection
Huanxin Chen, Chun Xia, Hechao Chen
https://arxiv.org/abs/2403.12497

Formation of Polar Crown Filaments Magnetic Fields by Supergranular Helicity Injection
To understand the magnetic fields of the polar crown filaments (PCFs) at high latitudes near polar regions of the Sun, we perform magnetofrictional numerical simulations on the long-term magnetic evolution of bipolar fields with roughly east-west polarity inversion lines (PILs) in a three-dimensional (3D) spherical wedge domain near polar regions. The Coriolis effect induced vortical motions at the boundaries of several supergranular cells inject magnetic helicity from the photospheric boundary…

Collective self-caging of active filaments in virtual confinement
Maximilian Kurjahn, Leila Abbaspour, Franziska Papenfu{\ss}, Philip Bittihn, Ramin Golestanian, Beno\^it Mahault, Stefan Karpitschka
https://arxiv.org/abs/2403.03093

Collective self-caging of active filaments in virtual confinement
Motility coupled to responsive behavior is essential for many microorganisms to seek and establish appropriate habitats. One of the simplest possible responses, reversing the direction of motion, is believed to enable filamentous cyanobacteria to form stable aggregates or accumulate in suitable light conditions. Here, we demonstrate that filamentous morphology in combination with responding to light gradients by reversals has consequences far beyond simple accumulation: Entangled aggregates for…

The nature of the X-ray filaments around bow shock pulsar wind nebulae
Barbara Olmi, Elena Amato, Rino Bandiera, Pasquale Blasi
https://arxiv.org/abs/2403.03616

The nature of the X-ray filaments around bow shock pulsar wind nebulae
Context. We propose that the X-ray filaments emerging from selected bow shock pulsar wind nebulae are due to a charge-separated outflow of electrons and/or positrons escaping the nebula and propagating along the local Galactic magnetic field. Aims. The X-ray brightness, length, and thickness of filaments are all accounted for if a nonresonant streaming instability is excited. Methods. This is possible if particles are released in the interstellar medium as a collimated beam, as would be expecte…

The vibe of 3D printing with filaments reminds me of old hard drives defragging. #PC #Windows #Defragment #3DPrinting

Localization-delocalization transition for light particles in turbulence
Ziqi Wang, Xander M de Wit, Federico Toschi
https://arxiv.org/abs/2403.10630 https…

Localization-delocalization transition for light particles in turbulence
Small bubbles in fluids raise to the surface due to Archimede's force. Remarkably, in turbulent flows this process is severely hindered by the presence of vortex filaments, which act as moving potential wells, dynamically trapping light particles and bubbles. Quantifying the statistical weights and roles of vortex filaments in turbulence is, however, still an outstanding experimental and computational challenge due to their small scale, fast chaotic motion, and transient nature. Here we show th…

Giant Biconical Dust Filaments in the Starburst Galaxy NGC 1808
Rohan KaneUniversity of Maryland, College Park, Sylvain VeilleuxUniversity of Maryland, College Park
https://arxiv.org/abs/2403.02427 https://arxiv.org/pdf/2403.02427
arXiv:2403.02427v1 Announce Type: new
Abstract: We present the results from an analysis of multi-wavelength archival data on the multi-phase outflow in the starburst galaxy NGC 1808. We report the detection at 70 and 100 um of dust filaments that extend up to ~ 13 kpc from the galactic mid-plane and trace an edge-brightened biconical structure along the minor axis of the galaxy. The inner filaments are roughly co-spatial with previously identified optical dust filaments, extraplanar polycyclic aromatic hydrocarbon emission, and neutral and ionized gaseous outflows. The 70/160 um flux ratio, a proxy for dust temperature, is elevated along the edges of the cones, indicating that the dusty medium has been driven out of the central regions of these cones and possibly shock-heated by an outflow. We establish lower limits on the extraplanar dust mass and mean height above the stellar disk of log(M_d/M_sun) = 6.48 and |z| ~ 5 kpc, respectively. The energy requirement of (5.1-9.6) x 10^{56} ergs needed to lift the dusty material, assuming Milky-Way like dust-to-gas ratio, can be supplied by the current starburst, with measured star formation rate of 3.5-5.4 M_sun yr^{-1}, over a timescale of (4-26) xi^{-1} Myr, where xi is the efficiency of energy transfer. We conclude that a starburst-driven outflow is the most likely mechanism by which the dust features were formed.

Onset of penumbra formation
M. Garc\'ia-Rivas, J. Jur\v{c}\'ak, N. Bello Gonz\'alez, J. M. Borrero, R. Schlichenmaier, P. Lindner
https://arxiv.org/abs/2403.18455

Onset of penumbra formation
Context. Fully fledged penumbrae have been widely studied both observationally and theoretically. Yet the relatively fast process of penumbra formation has not been studied closely with high spatial resolution. Aims. We investigate the stages previous to and during the formation of penumbral filaments in a developing sunspot. Methods. We analysed Milne-Eddington inversions from spectro-polarimetric data of the leading sunspot of NOAA 11024 during the development of its penumbra. We focused on s…

Can the splashback radius be an observable boundary of galaxy clusters?
Th\'eo Lebeau, Stefano Ettori, Nabila Aghanim, Jenny G. Sorce
https://arxiv.org/abs/2403.18648

Can the splashback radius be an observable boundary of galaxy clusters?
The splashback radius was proposed as a physically motivated boundary of clusters as it sets the limit between the infalling and the orbitally dominated regions. However, galaxy clusters are complex objects connected to filaments of the cosmic web from which they accrete matter that disturbs them and modifies their morphology. In this context, estimating the splashback radius and the cluster boundary becomes challenging. In this work, we use a constrained hydrodynamical simulation of the Virgo …

INvestigations of massive Filaments ANd sTar formation (INFANT). I. Core Identification and Core Mass Function
Yu Cheng, Xing Lu, Patricio Sanhueza, Hauyu Baobab Liu, Qizhou Zhang, Roberto Galv\'an-Madrid, Ke Wang, Fumitaka Nakamura, Tie Liu, Siyi Feng, Shanghuo Li, Sihan Jiao, Kei E. I. Tanaka, Xunchuan Liu, Pak Shing Li, Qiuyi Luo, Qilao Gu, Yuxin Lin, Andr\'as E. Guzm\'an

INvestigations of massive Filaments ANd sTar formation (INFANT). I. Core Identification and Core Mass Function
Filamentary structures are ubiquitously found in high-mass star-forming clouds. To investigate the relationship between filaments and star formation, we carry out the INFANT (INvestigations of massive Filaments ANd sTar formation) survey, a multi-scale, multi-wavelength survey of massive filamentary clouds with ALMA band 3/band 6 and VLA K band. In this first paper, we present the ALMA band 6 continuum observations toward a sample of 8 high-mass star forming filaments. We covered each target wi…

Advecting Scaffolds: Controlling The Remodelling Of Actomyosin With Anillin
Denni Currin-RossCentre for Cell Biology of Chronic Disease, Institute for Molecular Bioscience, The University of Queensland, Australia, EMBL Australia Node in Single Molecule Science, School of Biomedical Sciences, UNSW, Australia, Sami C. Al-IzziDepartment of Mathematics, Faculty of Mathematics and Natural Sciences, University of Oslo, Norway, Ivar NoordstraCentre for Cell Biology of Chronic Disease, Institu…

Advecting Scaffolds: Controlling The Remodelling Of Actomyosin With Anillin
We propose and analyse an active hydrodynamic theory that characterises the effects of the scaffold protein anillin. Anillin is found at major sites of cortical activity, such as adherens junctions and the cytokinetic furrow, where the canonical regulator of actomyosin remodelling is the small GTPase, RhoA. RhoA acts via intermediary 'effectors' to increase both the rates of activation of myosin motors and the polymerisation of actin filaments. Anillin has been shown to scaffold this action of …

Synthetic active liquid crystals powered by acoustic waves
Andrey Sokolov, Jaideep Katuri, Juan J. de Pablo, Alexey Snezko
https://arxiv.org/abs/2403.17268

Synthetic active liquid crystals powered by acoustic waves
Active nematics are materials composed of mobile, elongated particles that can transform energy from the environment into a mechanical motion. Current experimental realizations of the active nematics are of biological origin and include cell layers, suspensions of elongated bacteria in liquid crystal, and combinations of bio-filaments with molecular motors. Here, we report the realization of a fully synthetic active nematic system comprised of a lyotropic chromonic liquid crystal energized by u…

This https://arxiv.org/abs/2311.15413 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

On the Cauchy problem for 3D Navier-Stokes helical vortex filament
This paper studies the Cauchy problem for a helical vortex filament evolving by the 3D incompressible Navier-Stokes equations. We prove global-in-time well-posedness and smoothing of solutions with initial vorticity concentrated on a helix. We provide a local-in-time well-posedness result for vortex filaments periodic in one spatial direction, and show that solutions with helical initial data preserve this symmetry. We follow the approach of [4], where the analogue local-in-time result has been…

Unveiling the Cosmic Cradle: clustering and massive star formation in the enigmatic Galactic bubble N59
Sonu Tabitha Paulson, K. K. Mallick, D. K. Ojha
https://arxiv.org/abs/2403.19252

Unveiling the Cosmic Cradle: clustering and massive star formation in the enigmatic Galactic bubble N59
In this paper, we have conducted an investigation focused on a segment of the $Spitzer$ mid-infrared bubble N59, specifically referred to as R1 within our study. Situated in the inner Galactic plane, this region stands out for its hosting of five 6.7 GHz methanol masers, as well as numerous compact H II regions, massive clumps, filaments, and prominent bright rims. As 6.7 GHz masers are closely linked to the initial phases of high-mass star formation, exploring regions that exhibit a high abund…

Riemannian L-systems: Modeling growing forms in curved spaces
Christophe Godin, Fr\'ed\'eric Boudon
https://arxiv.org/abs/2404.03270 https://

Riemannian L-systems: Modeling growing forms in curved spaces
In the past 50 years, the formalism of L-systems has been successfully used and developed to model the growth of filamentous and branching biological forms. These simulations take place in classical 2-D or 3-D Euclidean spaces. However, various biological forms actually grow in curved, non-Euclidean, spaces. This is for example the case of vein networks growing within curved leaf blades, of unicellular filaments, such as pollen tubes, growing on curved surfaces to fertilize distant ovules, of t…

The CAVITY project. The spatially resolved stellar population properties of galaxies in voids
Ana M. Conrado, Rosa M. Gonz\'alez Delgado, Rub\'en Garc\'ia-Benito, Isabel P\'erez, Simon Verley, Tom\'as Ruiz-Lara, Laura S\'anchez-Menguiano, Salvador Duarte Puertas, Andoni Jim\'enez, Jes\'us Dom\'inguez-G\'omez, Daniel Espada, Mar\'ia Argudo-Fern\'andez, Manuel Alc\'azar-Laynez, Guillermo Bl\'azquez-Calero, Bahar Bidaran, Almudena Zu…

The CAVITY project. The spatially resolved stellar population properties of galaxies in voids
The Universe is shaped as a web-like structure, formed by clusters, filaments, and walls that leave large volumes in between named voids. Galaxies in voids have been found to be of a later type, bluer, less massive, and to have a slower evolution than galaxies in denser environments (filaments and walls). However, the effect of the void environment on their stellar population properties is still unclear. We aim to address this question using 118 optical integral field unit datacubes from the Ca…

Modification to the Jeans criterion by external tides: Anisotropic fragmentation and formation of filaments
Guang-Xing Li
https://arxiv.org/abs/2403.02612 https://arxiv.org/pdf/2403.02612
arXiv:2403.02612v1 Announce Type: new
Abstract: The Jeans criterion sets the foundation of our understanding of gravitational collapse. Jog studied the fragmentation of gas under external tides and derived a dispersion relation $$
l' = l_{\rm Jeans} \frac{1} {(1 \lambda_0' / 4 \pi G \rho_0)^{1/2}} \;. $$ She further concludes that the Jeans mass is $m_{\rm incorrect}'=m_{\rm Jeans} ( 1/(1 \lambda_0' / 4 \pi G \rho_0)^{3/2})$. We clarify that due to the inhomogeneous nature of tides, this characteristic mass is incorrect. Under weak tides, the mass is $m \approx \rho\, l_1 l_2 l_3$, where the modifications to Jeans lengths along all three dimensions need to be considered; when the tide is strong enough, collapse can only occur once 1 or 2 dimensions. In the latter case, tides can stretch the gas, leading to the formation of filaments.

This https://arxiv.org/abs/1907.00469 has been replaced.
link: https://scholar.google.com/scholar?q=a

Spontaneous Domain Formation in Spherically-Confined Elastic Filaments
Although the free energy of a genome packing into a virus is dominated by DNA-DNA interactions, ordering of the DNA inside the capsid is elasticity-driven, suggesting general solutions with DNA organized into spool-like domains. Using analytical calculations and computer simulations of a long elastic filament confined to a spherical container, we show that the ground state is not a single spool as assumed hitherto, but an ordering mosaic of multiple homogeneously-ordered domains. At low densiti…

The SRG/eROSITA All-Sky Survey: First catalog of superclusters in the western Galactic hemisphere
A. Liu, E. Bulbul, M. Kluge, V. Ghirardini, X. Zhang, J. S. Sanders, E. Artis, Y. E. Bahar, F. Balzer, M. Brueggen, N. Clerc, J. Comparat, C. Garrel, E. Gatuzz, S. Grandis, G. Lamer, A. Merloni, K. Migkas, K. Nandra, P. Predehl, M. E. Ramos-Ceja, T. H. Reiprich, R. Seppi, S. Zelmer

The SRG/eROSITA All-Sky Survey: First catalog of superclusters in the western Galactic hemisphere
Superclusters of galaxies mark the large-scale overdense regions in the Universe. Superclusters provide an ideal environment to study structure formation and to search for the emission of the intergalactic medium such as cosmic filaments and WHIM. In this work, we present the largest-to-date catalog of X-ray-selected superclusters identified in the first SRG/eROSITA All-Sky Survey (eRASS1). By applying the Friends-of-Friends method on the galaxy clusters detected in eRASS1, we identified 1338 s…

Bimodal orientation distribution and head-tail asymmetry of a sample of filamentary molecular clouds
Wen Ge, Fujun Du, Lixia Yuan
https://arxiv.org/abs/2403.16518

Bimodal orientation distribution and head-tail asymmetry of a sample of filamentary molecular clouds
The morphology of molecular clouds is crucial for understanding their origin and evolution. In this work, we investigate the morphology of the filamentary molecular clouds (filaments for short) using a portion of the $^{12}\text{CO} (J=1-0)$ data from the Milky Way Imaging Scroll Painting (MWISP) project. The data cover an area spanning $104.75^\circ

Observations of spiral and streamer on a candidate proto-brown dwarf
B. Riaz, D. Stamatellos, M. Machida
https://arxiv.org/abs/2403.07367 https://

Observations of spiral and streamer on a candidate proto-brown dwarf
Spirals and streamers are the hallmarks of mass accretion during the early stages of star formation. We present the first observations of a large-scale spiral and a streamer towards a very young brown dwarf candidate in its early formation stages. These observations show, for the first time, the influence of external environment that results in asymmetric mass accretion via feeding filaments onto a candidate proto-brown dwarf in the making. The impact of the streamer has produced emission in wa…

This https://arxiv.org/abs/2309.03282 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

How galaxy properties vary with filament proximity in the SIMBA simulations
We explore the dependence of global galaxy properties in the SIMBA simulation as a function of distance from filaments identified using DisPerSe. We exclude halos with mass $M_h>10^{13}M_\odot$ to mitigate the impact of group and cluster environments. Galaxies near filaments are more massive and have more satellites, which we control for by examining deviations from best-fit scaling relations. At $z=0$, star formation (SF) is significantly suppressed within $\lesssim 100$ kpc of filaments, more…

High-throughput measurement of elastic moduli of microfibers by rope coiling
Yuan Liu, Jack Hau Yung Lo, Janine K. Nunes, Howard A. Stone, Ho Cheung Shum
https://arxiv.org/abs/2403.12225

High-throughput measurement of elastic moduli of microfibers by rope coiling
There are many fields where it is of interest to measure the elastic moduli of tiny fragile fibers, such as filamentous bacteria, actin filaments, DNA, carbon nanotubes, and functional microfibers. The elastic modulus is typically deduced from a sophisticated tensile test under a microscope, but the throughput is low and limited by the time-consuming and skill-intensive sample loading/unloading. Here, we demonstrate a simple microfluidic method enabling the high-throughput measurement of the el…

Observations of spiral and streamer on a candidate proto-brown dwarf
B. Riaz, D. Stamatellos, M. Machida
https://arxiv.org/abs/2403.07367 https://

Observations of spiral and streamer on a candidate proto-brown dwarf
Spirals and streamers are the hallmarks of mass accretion during the early stages of star formation. We present the first observations of a large-scale spiral and a streamer towards a very young brown dwarf candidate in its early formation stages. These observations show, for the first time, the influence of external environment that results in asymmetric mass accretion via feeding filaments onto a candidate proto-brown dwarf in the making. The impact of the streamer has produced emission in wa…

Irreversible dynamics of a continuum driven by active matter
John C. Neu, Stephen W. Teitsworth
https://arxiv.org/abs/2403.10728 https://

Irreversible dynamics of a continuum driven by active matter
We study the fluctuational behavior of overdamped elastic filaments (e.g., strings or rods) driven by active matter which induces irreversibility. The statistics of discrete normal modes are translated into the continuum of the position representation which allows discernment of the spatial structure of dissipation and fluctuational work done by the active forces. The mapping of force statistics onto filament statistics leads to a generalized fluctuation-dissipation relation which predicts the …

The interaction of a large-scale nuclear wind with the high velocity HII region G0.17 0.15
F. Yusef-Zadeh, Jun-Hui Zhao, R. Arendt, M. Wardle, M. Royster, L. Rudnick, J. Michail
https://arxiv.org/abs/2402.12450

The interaction of a large-scale nuclear wind with the high velocity HII region G0.17+0.15
We investigate the nature of a Galactic center source, G0.17+0.15, lying along the northern extension of the Radio Arc near l~0.2deg. G0.17+0.15 is an HII region located toward the eastern edge of the radio bubble, embedded within the highly polarized Galactic center eastern Lobe where a number of radio filaments appear to cross through the HII region. We report the detection of hydrogen and helium recombination lines with a radial velocity exceeding 140 km/s based on GBT and VLA observations. …

$Herschel$ investigation of cores and filamentary structures in L1251 located in the Cepheus flare
Divyansh Dewan, Archana Soam, Guo-Yin Zhang, Akhil Lasrado, Saikhom Pravash Singh, Chang Won Lee
https://arxiv.org/abs/2403.10901

$Herschel$ investigation of cores and filamentary structures in L1251 located in the Cepheus flare
Context: Molecular clouds are the prime locations of star formation. These clouds contain filamentary structures and cores which are crucial in the formation of young stars. Aims: In this work, we aim to quantify the physical properties of structural characteristics within the molecular cloud L1251 to better understand the initial conditions for star formation. Methods: We applied the getsf algorithm to identify cores and filaments within the molecular cloud L1251 using the Herschel multiband d…

How do polymers stretch in capillary-driven extensional flows?
Vincenzo Calabrese, Amy Q. Shen, Simon J. Haward
https://arxiv.org/abs/2403.04103 https://…

How do polymers stretch in capillary-driven extensional flows?
Measurements of the capillary-driven thinning and breakup of fluid filaments are widely used to extract extensional rheological properties of complex materials. For viscoelastic (e.g., polymeric) fluids, the determination of the longest relaxation time depends on several assumptions concerning the polymeric response to the flow that are derived from constitutive models. Our capillary thinning experiments using polymeric fluids with a wide range of extensibility, suggest that these assumptions a…

This https://arxiv.org/abs/2310.20184 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

Graph Theoretic Approach Identifies Critical Thresholds at which Galaxy Filamentary Structures Form
Numerical simulations and observations show that galaxies are not uniformly distributed. In cosmology, the largest known structures in the universe are galaxy filaments formed from the hierarchical clustering of galaxies due to gravitational forces. These structures consist of walls and bridges that connect clusters. Here, we use graph theory to model the structures as Euclidean networks in three-dimensional space. Using percolation theory, cosmological graphs are reduced based on the valency o…

This https://arxiv.org/abs/2403.01298 has been replaced.
link: https://scholar.google.com/scholar?q=a

Spontaneous assembly of condensate networks during the demixing of structured fluids
Liquid-liquid phase separation, whereby two liquids spontaneously demix, is ubiquitous in industrial, environmental, and biological processes. While isotropic fluids are known to condense into spherical droplets in the binodal region, these dynamics are poorly understood for structured fluids. Here, we report the novel observation of condensate networks, which spontaneously assemble during the demixing of a mesogen from a solvent. Condensing mesogens form rapidly-elongating filaments, rather th…

This https://arxiv.org/abs/2312.10146 has been replaced.
link: https://scholar.google.com/scholar?q=a

Star Formation and Dust in the Cosmic Web
The large-scale environment of the cosmic web is believed to impact galaxy evolution, but there is still no consensus regarding the mechanisms. We use a semi-analytic model (SAM) galaxy catalog to study the star formation and dust content of local galaxies in different cosmic environments of the cosmic web, namely voids, filaments, walls, and nodes. We find a strong impact of the environment only for galaxies with $M_{\rm stars}\lesssim10^{10.8}\, M_\odot$: the less dense the environment, the l…