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Related papers: A microwave plasma source for VUV atmospheric phot…

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UV, optical, and near-IR spectra of Vega have been combined to test our understanding of stellar atmospheric opacities, and to examine the possibility of constraining chemical abundances from low-resolution UV fluxes. We have carried out a…

Tunable biphotons are highly important for a wide range of quantum applications. For some applications, especially interesting are cases where two photons of a pair are far apart in frequency. Here, we report a tunable biphoton source based…

The shape of the spectral energy distribution of active galaxies in the EUV--soft X-ray band (13.6 eV to 1 keV) is uncertain because obscuration by dust and gas can hamper our view of the continuum. To investigate the shape of the spectral…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 M. Meléndez , S. B. Kraemer , K. A. Weaver , R. F. Mushotzky

We have observed atmospheric gamma rays from 30GeV to 8TeV, using emulsion chambers at balloon altitudes, accumulating the largest total exposure in this energy range to date, SOT ~ 6.66m^2.sr.day. At very high altitudes, with residual…

Astrophysics · Physics 2008-11-26 K. Yoshida , R. Ohmori , T. Kobayashi , Y. Komori , Y. Sato , J. Nishimura

The results of an extensive operation of a Vacuum Spark plasma using Titanium electrodes in a 120 ns 150 kA discharge are presented. The hot spots are found to form with a regular spacing in a zippering Z-pinch plasma, which forms close to…

Plasma Physics · Physics 2016-11-15 Edmund S. Wyndham , Mario Favre , Hernán Chuaqui , Peter Choi , Ana M. Leñero , Jorge S. Díaz

Context. Photochemistry is a key process driving planetary atmospheres away from local thermodynamic equilibrium. Recent observations of the H$_2$ dominated atmospheres of hot gas giants have detected SO$_2$ as one of the major products of…

Earth and Planetary Astrophysics · Physics 2025-01-15 Wiebe de Gruijter , Shang-Min Tsai , Michiel Min , Rens Waters , Thomas Konings , Leen Decin

The diffuse flux of cosmic neutrinos has been measured by the IceCube Observatory from TeV to PeV energies. We show that an improved characterization of this flux at the lower energies, TeV and sub-TeV, reveals important information on the…

High Energy Astrophysical Phenomena · Physics 2022-07-20 Ke Fang , John S. Gallagher , Francis Halzen

We present a new, on-the-fly photon flux and absorption tracer algorithm designed to directly measure the contribution of different source populations to the metagalactic UV background and to the ionisation fraction of gas in the Universe.…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-06 Harley Katz , Taysun Kimm , Martin Haehnelt , Debora Sijacki , Joakim Rosdahl , Jeremy Blaizot

This study employs a quasi-1.5D multi-temperature model to investigate the mechanisms governing NOx production and energy costs in microwave plasma reactors operating at 80 mbar, focusing on the interplay of vibrational, chemical and…

We report on a compact and spectrally intense extreme-ultraviolet (XUV) source, which is based on high-harmonic generation (HHG) driven by 395 nm pulses. In order to minimize the XUV virtual source size and to maximize the XUV flux, HHG is…

Optics · Physics 2021-07-01 M. Kretschmar , M. J. J. Vrakking , B. Schütte

A new category of plasma emerged at the end of the 1970s. It consists of a column of plasma maintained by the electric field component of radiofrequency (RF) and microwave (MW) waves that propagate at the interface between the outer surface…

Plasma Physics · Physics 2026-04-20 Michel Moisan

The electron and gas temperature of non-equilibrium argon plasma torch sustained by a focused 24 GHz microwave beam in the external atmosphere of air was measured by optical emission spectroscopy. The excitation temperature of argon atoms…

This paper describes the construction and performance of a VUV-simulator that has been designed to study degradation of materials under space conditions. It is part of the Complex Irradiation Facility at DLR in Bremen, Germany, that has…

Instrumentation and Detectors · Physics 2014-06-09 Maciej Sznajder , Thomas Renger , Andreas Witzke , Ulrich Geppert , Reiner Thornagel

Very-high-energy astronomy studies the Universe at energies between 30 GeV and 100 TeV. The past decade has seen enormous progress in this field. There are now at least seven known sources of VHE photons. By studying these objects in the…

Astrophysics · Physics 2009-09-25 Gus Sinnis

Most exoplanets detected so far have atmospheric T significantly higher than 300K. Often close to their star, they receive an intense UV photons flux that triggers important photodissociation processes. The T dependency of VUV absorption…

To evaluate the feasibility of the recently proposed detection scheme of low energy neutrinos released from the Sun and supernovae called CLEAN, Cryogenic Low Energy Astrophysics with Noble Gases, which relies on the transparency of…

Atomic Physics · Physics 2009-11-10 I. M. Savukov

Vacuum ultraviolet (VUV) light is critical for the study of molecules and materials, but the generation of femtosecond pulses in the VUV region at high repetition rates has proven difficult. Here, we demonstrate the efficient generation of…

High harmonic generation (HHG) enables coherent extreme-ultraviolet (XUV) radiation with ultra-short pulse duration in a table-top setup. This has already enabled a plethora of applications. Nearly all of these applications would benefit…

Optics · Physics 2021-06-07 R. Klas , A. Kirsche , M. Gebhardt , J. Buldt , H. Stark , S. Hädrich , J. Rothhardt , J. Limpert

Ice mantles detected on the surface of dust grains toward the coldest regions of the interstellar medium can be photoprocessed by the secondary ultraviolet (UV) field present in dense cloud interiors. In this work, we present UV-irradiation…

Astrophysics of Galaxies · Physics 2017-11-15 R. Martin-Domenech , G. A. Cruz-Diaz , G. M. Munoz Caro

This chapter describes the basic principles, design features and characteristics of microwave discharge ion sources. A suitable source for the production of intense beams for high-power accelerators must satisfy the requirements of high…

Accelerator Physics · Physics 2014-11-04 L. Celona