Tootfinder

Subset Adaptive Relaying for Streaming Erasure Codes
Muhammad Ahmad Kaleem, Gustavo Kasper Facenda, Ashish Khisti
https://arXiv.org/abs/2401.15056 https://…

Subset Adaptive Relaying for Streaming Erasure Codes
Muhammad Ahmad Kaleem, Gustavo Kasper Facenda, Ashish Khisti
https://arXiv.org/abs/2401.15056 https://…

The fast X-ray transient EP240315a: a z ~ 5 gamma-ray burst in a Lyman continuum leaking galaxy
Andrew J. Levan, Peter G. Jonker, Andrea Saccardi, Daniele Bj{\o}rn Malesani, Nial R. Tanvir, Luca Izzo, Kasper E. Heintz, Daniel Mata S\'anchez, Jonathan Quirola-V\'asquez, Manuel A. P. Torres, Susanna D. Vergani, Steve Schulze, Andrea Rossi, Paolo D'Avanzo, Benjamin Gompertz, Antonio Martin-Carrillo, Antonio de Ugarte Postigo, Benjamin Schneider, Weimin Yuan, Zhixing Ling, Wenj…

The fast X-ray transient EP240315a: a z ~ 5 gamma-ray burst in a Lyman continuum leaking galaxy
The nature of the minute-to-hour long Fast X-ray Transients (FXTs) localised by telescopes such as Chandra, Swift, and XMM-Newton remains mysterious, with numerous models suggested for the events. Here, we report multi-wavelength observations of EP240315a, a 1600 s long transient detected by the Einstein Probe, showing it to have a redshift of z=4.859. We measure a low column density of neutral hydrogen, indicating that the event is embedded in a low-density environment, further supported by di…

Characterization of Turbulent Fluctuations in the Sub-Alfvenic Solar Wind
Gary P. Zank, Lingling Zhao, Laxman Adhikari, Daniele Telloni, Prashant Baruwal, Prashrit Baruwal, Xingyu Zhu, Masaru Nakanotani, Alexander Pitna, Justin C. Kasper, Stuart D. Bale
https://arxiv.org/abs/2403.14861 <…

Characterization of Turbulent Fluctuations in the Sub-Alfvenic Solar Wind
Parker Solar Probe (PSP) observed sub-Alfvenic solar wind intervals during encounters 8 - 14, and low-frequency magnetohydrodynamic turbulence in these regions may differ from that in super-Alfvenic wind. We apply a new mode-decomposition analysis (Zank et al 2023) to the sub-Alfvénic flow observed by PSP on 2021 April 28, identifying and characterizing entropy, magnetic islands, forward and backward Alfvén waves, including weakly/non-propagating Alfvén vortices, forward and backward fast an…

@… wenn du dich selber vor einer Gruppe etwas zum Kasper machst, hat es auch den Effekt, das man sich als Person in der Runde mehr „traut“.
Erlebe ich bei der Arbeit vor Gruppen auch.

Majority-of-Three: The Simplest Optimal Learner?
Ishaq Aden-Ali, Mikael M{\o}ller H{\o}gsgaard, Kasper Green Larsen, Nikita Zhivotovskiy
https://arxiv.org/abs/2403.08831

Majority-of-Three: The Simplest Optimal Learner?
Developing an optimal PAC learning algorithm in the realizable setting, where empirical risk minimization (ERM) is suboptimal, was a major open problem in learning theory for decades. The problem was finally resolved by Hanneke a few years ago. Unfortunately, Hanneke's algorithm is quite complex as it returns the majority vote of many ERM classifiers that are trained on carefully selected subsets of the data. It is thus a natural goal to determine the simplest algorithm that is optimal. In this…

Finding Moving-Band Statistical Arbitrages via Convex-Concave Optimization
Kasper Johansson, Thomas Schmelzer, Stephen Boyd
https://arxiv.org/abs/2402.08108

Finding Moving-Band Statistical Arbitrages via Convex-Concave Optimization
We propose a new method for finding statistical arbitrages that can contain more assets than just the traditional pair. We formulate the problem as seeking a portfolio with the highest volatility, subject to its price remaining in a band and a leverage limit. This optimization problem is not convex, but can be approximately solved using the convex-concave procedure, a specific sequential convex programming method. We show how the method generalizes to finding moving-band statistical arbitrages,…

Monitoring AGNs with H$\beta$ Asymmetry. IV. First Reverberation Mapping Results of 14 AGNs
T. E. Zastrocky, Michael S. Brotherton, Pu Du, Jacob N. McLane, Kianna A. Olson, D. A. Dale, H. A. Kobulnicky, Jaya Maithil, My L. Nguyen, William T. Chick, David H. Kasper, Derek Hand, C. Adelman, Z. Carter, G. Murphree, M. Oeur, T. Roth, S. Schonsberg, M. J. Caradonna, J. Favro, A. J. Ferguson, I. M. Gonzalez, L. M. Hadding, H. D. Hagler, C. J. Rogers, T. R. Stack, Franklin Chapman, Dong-Wei B…

Monitoring AGNs with H$β$ Asymmetry. IV. First Reverberation Mapping Results of 14 AGNs
We report first-time reverberation mapping results for 14 AGNs from the ongoing Monitoring AGNs with H$β$ Asymmetry campaign (MAHA). These results utilize optical spectra obtained with the Long Slit Spectrograph on the Wyoming Infrared 2.3m Telescope between 2017 November-2023 May. MAHA combines long-duration monitoring with high cadence. We report results from multiple observing seasons for 9 of the 14 objects. These results include H$β$ time lags, supermassive black hole masses, and velocit…

Origin and Properties of the Near Subsonic Solar Wind Observed by Parker Solar Probe
Wenshuai Cheng, Ying D. Liu, Hao Ran, Yiming Jiao, Michael L. Stevens, Justin C. Kasper
https://arxiv.org/abs/2404.05557

Origin and Properties of the Near Subsonic Solar Wind Observed by Parker Solar Probe
We identify and examine the solar wind intervals near the sonic critical point (i.e., $M_S \sim 1$) observed by the Parker Solar Probe (PSP). The near subsonic wind intervals show similar properties: a low density, an extremely low velocity, a low proton temperature, and essentially no magnetic field deflections compared with the surrounding solar wind. The extremely low velocity is the primary contributor to the near crossing of the sonic critical point rather than the sound speed, which is ro…

Uncovering the physical origin of the prominent Lyman-$\alpha$ emission and absorption in GS9422 at $z = 5.943$
Chamilla Terp, Kasper E. Heintz, Darach Watson, Gabriel Brammer, Adam Carnall, Joris Witstok, Renske Smit, Simone Vejlgaard
https://arxiv.org/abs/2404.06543

Uncovering the physical origin of the prominent Lyman-$α$ emission and absorption in GS9422 at $z = 5.943$
We present a comprehensive spectro-photometric analysis of the galaxy GS9422 from the JADES GTO survey located at $z=5.943$, anomalously showing a simultaneous strong Ly$α$ emission feature and damped Ly$α$ absorption (DLA), based on JWST NIRSpec and NIRCam observations. The best-fit modelling of the spectral energy distribution (SED) reveals a young, low-mass (${\rm log}(M_\star/M_{\odot}) = 7.8 \pm 0.01$) galaxy, with a mass-weighted mean age of the stellar population of $(10.9^{+0.07}_{-0.…