Cathode ray

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Cathode rays (also called an electron beam or e-beam) are streams of electrons observed in vacuum tubes, i.e. evacuated glass tubes that are equipped with at least two metal electrodes to which a voltage is applied, a cathode or negative electrode and an anode or positive electrode. They were discovered by German scientist Johann Hittorf in 1869 and in 1876 named by Eugen Goldstein kathodenstrahlen (cathode rays). Electrons were first discovered as the constituents of cathode rays. In 1897 British physicist J. J. Thompson showed the rays were composed of a previously unknown negatively charged particle, which was named electron.

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News tagged with electron beam


Caltech scientists film photons with electrons

Caltech scientists film photons with electrons

Physics / General Physics

created Dec 16, 2009 | popularity 4.9 / 5 (21) | comments 0

(PhysOrg.com) -- Techniques recently invented by researchers at the California Institute of Technology -- which allow the real-time, real-space visualization of fleeting changes in the structure of nanoscale ...


Microscopy reveals structure of calcite shells

Microscopy reveals structure of calcite shells

Chemistry / Materials Science

created Nov 30, 2009 | popularity 5 / 5 (1) | comments 0

(PhysOrg.com) -- Lara Estroff and colleagues have taken a deep, detailed look at the way lab-created calcite crystals, similar to those found in nature, grow in tandem with proteins and other large molecules.





Search results for electron beam


Accelerators and Light Sources of Tomorrow (Part 2: Accelerating with Light)

Accelerators and Light Sources of Tomorrow (Part 2: Accelerating with Light)

Physics / General Physics

created Dec 22, 2009 | popularity 4.9 / 5 (7) | comments 0

Accelerators are far from achieving the highest energies their builders aspire to, but size and cost may limit the kinds of facilities funding agencies can support. In the future, new kinds of machines will ...


Part 1: From Linacs to Lasers: Accelerators and Light Sources of Tomorrow

Accelerators and Light Sources of Tomorrow (Part 1: From Linacs to Lasers)

Physics / General Physics

created Dec 22, 2009 | popularity 4.7 / 5 (6) | comments 2

From their humble beginnings as offshoots of the ordinary electric light bulb, particle accelerators have evolved in surprising directions. Among the most productive and promising developments have been light ...


Beaming in on Warm Dense Matter (w/ Video)

Physics / General Physics

created Dec 17, 2009 | popularity 5 / 5 (3) | comments 0

(PhysOrg.com) -- The Neutralized Drift Compression Experiment II (NDCX-II) now under construction at Berkeley Lab will deliver a high-current pulse of lithium ions to a foil target almost simultaneously, momentarily heating ...


Miracle light: Can lasers solve the energy crisis?

Technology / Energy

created Dec 15, 2009 | popularity 4.4 / 5 (14) | comments 4

Next year will mark the 50th birthday of the laser, one of the most productive and widely used mega-inventions of the last century. Scientists hope that 2010 also will see the launch of laser technology's greatest challenge: ...


Micromachined piezoelectric harvester drives fully autonomous wireless sensor

Micromachined piezoelectric harvester drives fully autonomous wireless sensor

Technology / Engineering

created Dec 15, 2009 | popularity 5 / 5 (11) | comments 1

For the first time, a piezoelectric harvesting device fabricated by MEMS technology generates a record of 85μW electrical power from vibrations. A wafer level packaging method was developed for robustness. ...


Large Hadron Collider (LHC)

Large Hadron Collider produces first physics results

Physics / General Physics

created Dec 15, 2009 | popularity 4.4 / 5 (34) | comments 3

(PhysOrg.com) -- The first paper on proton collisions in the CERN Large Hadron Collider (LHC) - designed to provide the highest energy ever explored with particle accelerators - is published online this week ...


New structure could produce efficient semiconductor laser sources

New structure could produce efficient semiconductor laser sources

Physics / General Physics

created Dec 14, 2009 | popularity 4.7 / 5 (3) | comments 1

(PhysOrg.com) -- University of Wisconsin-Madison researchers have achieved a nanoscale laser structure they anticipate will produce semiconductor lasers in the next two years that are more than twice as efficient ...


Snowman

Scientists Create World's Smallest Snowman (w/ Video)

Nanotechnology / Nanophysics

created Dec 04, 2009 | popularity 3.5 / 5 (20) | comments 5 weblog

(PhysOrg.com) -- David Cox, a scientist in the Quantum Detection group at the National Physical Laboratory in the UK, is an expert in nanofabrication techniques. Recently, using the tools of his trade and ...


Lasers used to make first boron-nitride nanotube yarn

Lasers used to make first boron-nitride nanotube yarn (w/ Video)

Nanotechnology / Nanomaterials

created Dec 02, 2009 | popularity 4.8 / 5 (15) | comments 2

(PhysOrg.com) -- Researchers have used lasers to create the first practical macroscopic yarns from boron nitride fibers, opening the door for an array of applications, from radiation-shielded spacecraft to ...



List of search results for electron beam