A5100626529- Stellar, planetary, and galactic studies
- Cryptography and Data Security
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Pulsars and Gravitational Waves Research
- Astrophysics and Star Formation Studies
- Astronomy and Astrophysical Research
- Privacy-Preserving Technologies in Data
- Cryptographic Implementations and Security
- Particle physics theoretical and experimental studies
- Internet Traffic Analysis and Secure E-voting
- High-Energy Particle Collisions Research
- Complexity and Algorithms in Graphs
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Advanced Data Storage Technologies
- Advanced Authentication Protocols Security
- Quantum Chromodynamics and Particle Interactions
- Dark Matter and Cosmic Phenomena
- Cloud Data Security Solutions
- Astrophysics and Cosmic Phenomena
- User Authentication and Security Systems
- IPv6, Mobility, Handover, Networks, Security
- Adaptive optics and wavefront sensing
- High-pressure geophysics and materials
Tel Aviv University
2021-2025
Max Planck Institute for Astronomy
2023-2025
Johns Hopkins University
2012-2025
Centre for Environment, Fisheries and Aquaculture Science
2022-2025
The University of Adelaide
2025
University of Warwick
2017-2023
Western University
2020
Jupiter Medical Center
2019
Florida Atlantic University
2019
University of Redlands
2018
In 1998, Blaze, Bleumer, and Strauss (BBS) proposed an application called atomic proxy re-encryption , in which a semitrusted converts ciphertext for Alice into Bob without seeing the underlying plaintext. We predict that fast secure will become increasingly popular as method managing encrypted file systems. Although efficiently computable, wide-spread adoption of BBS has been hindered by considerable security risks. Following recent work Dodis Ivan, we present new schemes realize stronger...
We investigate the security of Diffie-Hellman key exchange as used in popular Internet protocols and find it to be less secure than widely believed. First, we present Logjam, a novel flaw TLS that lets man-in-the-middle downgrade connections "export-grade" Diffie-Hellman. To carry out this attack, implement number field sieve discrete log algorithm. After week-long precomputation for specified 512-bit group, can compute arbitrary logs group about minute. 82% vulnerable servers use single...
M dwarfs are prime targets in the hunt for habitable worlds around other stars. This is due to their abundance as well small radii and low masses temperatures, which facilitate detection of temperate, rocky planets orbit them. However, fundamental properties difficult constrain, often limiting our ability characterise they host. Here we test several theoretical relationships by measuring 23 high precision, model-independent binaries with white dwarfs. We find a large scatter these low-mass...
An aggregate signature scheme is a digital where anyone given n signatures on messages from users can all these into single short signature. Unfortunately, no "fully non-interactive" schemes are known outside of the random oracle heuristic; that is, signers must pass between themselves, sequentially or otherwise, to generate Interaction too costly for some interesting applications.
We present measurements of the component masses in 15 Cataclysmic Variables (CVs) – 6 new estimates and 9 improved estimates. provide calibrations relationship between superhump period excess mass ratio, use this relation to estimate donor star for 225 superhumping CVs. With an increased sample we revisit implications CV evolution. confirm high white dwarfs CVs, but find no trend dwarf with orbital period. argue a revision location minimum CVs 79.6 ± 0.2 min, significantly shorter than...
HiPERCAM is a portable, quintuple-beam optical imager that saw first light on the 10.4-m Gran Telescopio Canarias (GTC) in 2018. The instrument uses re-imaging optics and 4 dichroic beamsplitters to record $u_s g_s r_s i_s z_s$ ($320-1060$ nm) images simultaneously its five CCD cameras, each of 3.1 arcmin (diagonal) field view. detectors are frame-transfer devices cooled thermo-electrically 183 K, thereby allowing both long-exposure, deep imaging faint targets, as well high-speed (over 1000...
We present a homogeneously-selected sample of 15779 candidate binary systems with main sequence primary stars and orbital periods shorter than 5 days. The targets were selected from TESS full-frame image lightcurves on the basis their tidally-induced ellipsoidal modulation. Spectroscopic follow-up suggests purity $83 \pm 13$ per cent. Injection-recovery tests allow us to estimate our overall completeness as $28 3$ cent $P_\mathrm{orb} < days quantify selection effects. that $39 4$ are...
We have formalized the functional specification of HMAC-DRBG (NIST 800-90A), and we proved its cryptographic security-that output is pseudorandom--using a hybrid game-based proof. also that mbedTLS implementation (C program) correctly implements this specification. That proof composes with an existing C compiler correctness to guarantee, end-to-end, machine language program gives strong pseudorandomness. All proofs (hybrid games, verification, compiler, their composition) are machine-checked...
We present optical high-speed photometry of three millisecond pulsars with low-mass (<0.3 M⊙) white dwarf companions, bringing the total number such systems follow-up time-series to five. confirm detection pulsations in one system, companion PSR J1738+0333, and show that pulsation frequencies amplitudes are variable over many months. A full asteroseismic analysis for this star is underconstrained, but mode periods we observe consistent expectations an |$M_{\star }=0.16 - 0.19\,M_{\odot }$|...
AM CVn systems are ultra-compact, helium-rich, accreting binaries with degenerate or semi-degenerate donors. We report the discovery of five new eclipsing orbital periods 61.5, 55.5, 53.3, 37.4, and 35.4 minutes. These were discovered by searching for deep eclipses in Zwicky Transient Facility (ZTF) lightcurves white dwarfs selected using Gaia parallaxes. obtained phase-resolved spectroscopy to confirm that all binaries, we high-speed photometry eclipse characterize systems. The spectra two...
We present the discovery of a new double detonation progenitor system consisting hot subdwarf B (sdB) binary with white dwarf companion an P=76.34179(2) min orbital period. Spectroscopic observations are consistent sdB star during helium core burning residing on extreme horizontal branch. Chimera light curves dominated by ellipsoidal deformation and weak eclipse dwarf. Combining spectroscopic curve fits we find low mass star, $M_{\rm sdB}=0.383\pm0.028$ M$_\odot$ massive companion,...
A shift in environmental conditions impacts the evolution of complex developmental and behavioral traits. The Mexican cavefish, Astyanax mexicanus, is a powerful model for examining development, physiology, behavior because multiple cavefish populations can be compared to an extant, ancestral-like surface population same species. Many behaviors have diverged cave A. previous studies shown that loss sleep, reduced stress, absence social behaviors, hyperphagia. Despite these findings,...
We present optical photometry of the cataclysmic variable LAMOST J024048.51+195226.9 taken with high-speed, five-band CCD camera HiPERCAM on 10.4 m Gran Telescopio Canarias (GTC). detect pulsations originating from spin its white dwarf, finding a period 24.9328(38)s. The pulse amplitude is order 0.2% in g-band, below detection limits previous searches. This establishes as only second dwarf magnetic propeller system, twin long-known predecessor, AE Aquarii. At 24.93s, has shortest known any...
Wide-field time-domain photometric sky surveys are now finding hundreds of eclipsing white dwarf plus M binaries, a population encompassing wealth information and potential insight into close binary astrophysics. Precise follow-up observations essential in order to fully constrain these systems capitalise on the power this sample. We present first results from our program high-speed, multi-band follow-up. develop method measure temperatures, (model-dependent) masses, radii for both...