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Related papers: The FLASH enigma

200 papers

Hawking radiation is often intuitively visualized as particles that have tunneled across the horizon. Yet, at first sight, it is not apparent where the barrier is. Here I show that the barrier depends on the tunneling particle itself. The…

High Energy Physics - Theory · Physics 2008-11-26 Maulik K. Parikh

High-brightness electron bunches, such as those generated and accelerated in free-electron lasers (FELs), can develop small-scale structure in the longitudinal phase space. This causes variations in the slice energy spread and current…

Radiotherapy is a commonly used treatment for cancer and is usually given in varying doses. At low radiation doses relatively few cells die as a direct response to radiation but secondary radiation effects such as DNA mutation or bystander…

Quantitative Methods · Quantitative Biology 2016-06-16 Gibin G Powathil , Alastair J Munro , Mark AJ Chaplain , Maciej Swat

Gamma ray bursts are among the most energetic events in the known universe. A highly relativistic fireball is ejected. In most cases the burst itself is followed by an afterglow, emitted under deceleration as the fireball plunges through…

Astrophysics · Physics 2007-05-23 T. Haugboelle , C. B. Hededal , J. T. Frederiksen , A. Nordlund

The threshold properties of photonic crystal quantum dot lasers operating in the slow-light regime are investigated experimentally and theoretically. Measurements show that, in contrast to conventional lasers, the threshold gain attains a…

It is shown that the charged particles are refracted and reflected on the boundary of field free and laser field regions in vacuum. Simple and transparent estimates are given which show the possibility of channeling of charged and neutral…

Accelerator Physics · Physics 2007-07-19 X. Artru , K. A. Ispirian , M. K. Ispiryan

Gamma-ray bursts are believed to originate from internal shocks which arise in an irregular relativistic wind. The process has been thought to be inefficient, converting only a few percent of the kinetic energy into gamma-rays. We define…

Astrophysics · Physics 2009-11-06 Shiho Kobayashi , Re'em Sari

Most cancers in humans are large, measuring centimeters in diameter, composed of many billions of cells. An equivalent mass of normal cells would be highly heterogeneous as a result of the mutations that occur during each cell division.…

Populations and Evolution · Quantitative Biology 2016-02-17 Bartlomiej Waclaw , Ivana Bozic , Meredith E. Pittman , Ralph H. Hruban , Bert Vogelstein , Martin A. Nowak

FLASH is a new treatment modality that requires optimization of dose, dose rate, and LET. Here we validate these three quantities under FLASH conditions, which includes the quantum uncertainty in the time-dependent instantaneous dose rate…

This paper explores fluctuations and noise in various facets of cancer development. The three areas of particular focus are the stochastic progression of cells to cancer, fluctuations of the tumor size during treatment, and noise in cancer…

Cell Behavior · Quantitative Biology 2009-11-10 Matthew J. Berryman , Sabrina L. Spencer , Andrew Allison , Derek Abbott

It is currently not known if repeating fast radio bursts (FRBs) are fundamentally different from those that have not been seen to repeat. One striking difference between repeaters and apparent non-repeaters in the CHIME sample is that the…

High Energy Astrophysical Phenomena · Physics 2020-07-29 L. Connor , M. C. Miller , D. W. Gardenier

In this paper, we investigate the energy function, formation rate and environment of fast radio bursts (FRBs) using Parkes sample and Australian Square Kilometer Array Pathfinder (ASKAP) sample. For the first time, the metallicity effect on…

High Energy Astrophysical Phenomena · Physics 2019-06-19 G. Q. Zhang , F. Y. Wang

A disordered structure embedding an active gain material and able to lase is called random laser (RL). The RL spectrum may appear either like a set of sharp resonances or like a smooth line superimposed to the fluorescence. A recent letter…

Optics · Physics 2015-06-03 M. Leonetti , C. Conti , C. Lopez

The spatial range for feedback from star formation varies from molecular cloud disruption on parsec scales to supershells and disk blowout on kiloparsec scales. The relative amounts of energy and momentum given to these scales is important…

Astrophysics of Galaxies · Physics 2022-04-13 Bruce G. Elmegreen , Zorayda Martinez , Deidre A. Hunter

We investigate the properties of the optical model wave function for light heavy-ion systems where absorption is incomplete, such as $\alpha + ^{40}$Ca and $\alpha + ^{16}$O around 30 MeV incident energy. Strong focusing effects are…

Nuclear Theory · Physics 2008-11-26 F. Brau , F. Michel , G. Reidemeister

We study the joint effect of thermal bath fluctuations and an external noise tuning activity of cytotoxic cells on the triggered immune response in a growing cancerous tissue. The immune response is assumed to be primarily mediated by…

Populations and Evolution · Quantitative Biology 2015-06-26 Anna Ochab-Marcinek , Ewa Gudowska-Nowak

We observe interference in the light scattered from trapped $^{40}$Ca$^+$ ion crystals. By varying the intensity of the excitation laser, we study the influence of elastic and inelastic scattering on the visibility of the fringe pattern and…

Quantum Physics · Physics 2016-05-11 Sebastian Wolf , Julian Wechs , Joachim von Zanthier , Ferdinand Schmidt-Kaler

Molecular clouds interacting with supernova remnants may be subject to a greatly enhanced irradiation by cosmic rays produced at the shocked interface between the ejecta and the molecular gas. Over the past decade, broad-band observations…

Astrophysics · Physics 2009-11-11 M. Fatuzzo , F. C. Adams , F. Melia

Plasma supports electromagnetic waves propagation for frequencies higher than plasma frequency but features dielectric permittivity less than 1. This property leads to photon density of states (DOS) lower than in vacuum and should result in…

Optics · Physics 2023-03-21 S. V. Gaponenko , D. V. Guzatov , D. V. Novitsky

We develop an analytical theory of coherent (scaled quadratically with the number of particles) radiation and coherent radiation friction in a head-on collision of a dense charged particle bunch with an intense laser pulse. We demonstrate…

Plasma Physics · Physics 2026-05-28 E. G. Gelfer , A. M. Fedotov , M. P. Malakhov , Th. Benahmed , J. Custodio , O. Klimo , S. Weber