Project Excalibur

Project Excalibur was a Lawrence Livermore National Laboratory (LLNL) Cold War–era research program to develop an X-ray laser system as a ballistic missile defense (BMD) for the United States.

[8] In June 1977, two well-known Soviet researchers, Igor Sobel'man, and Vladilen Letokhov, displayed a film exposed to the output of plasmas of chlorine, calcium and titanium, similar to the Utah results.

This allowed the laser to be placed at the top of the vertical access shaft, which greatly lowered the cost of the test from the typical $40 million needed in a DNA shot.

George Miller received a "caustic" letter from Paul Robinson of Los Alamos, which stated they "doubted the existence of the X-ray laser had been demonstrated and that Livermore managers were losing their credibility because of their failure to stand up to Teller and Wood.

Once again the test appeared to be successful, and unnamed researchers at the lab were reported to have said the brightness of the beam had been increased six orders of magnitude (i.e. between one and ten million times), a huge advance that would pave the way for a weapon.

In contrast, George H. Miller, LLNL's new deputy associate director, set a much more cautious tone, stating that while the lasing action had been demonstrated, "what we have not proven is whether you can make a militarily useful X-ray laser.

It's a research program where a lot of the physics and engineering issues are still being examined ..."[62] Several months later, physicists at Los Alamos reviewed the Cottage results and noted the same problem Maenchen had mentioned earlier.

[38] On top of this, Livermore scientists studying the results noted that the explosion created sound waves in the rod before the lasing was complete, ruining the focus of the laser.

DeWitt and Ray Kidder then wrote to Edward Kennedy and Ed Markey to complain that LLNL's objection to ongoing talks of a nuclear test ban rested solely on the X-ray program.

This was the case for the free electron laser, for instance, where the panel was able to offer specific information on the required improvements, calling for two or more orders of magnitude in energy (100 times).

[76] In contrast, the report's section on Excalibur suggested it was not clear it could ever work even in theory and was summarized thus: Nuclear explosion pumped X-ray lasers require validation of many of the physical concepts before their application to strategic defense can be evaluated.

[86] The GAO report stated that they found a wide variety of opinions on the X-ray laser project, but Teller and Wood were "essentially off the scale on the optimistic side".

By the late 1980s, the entire concept was being derided in the press and by other members of the lab; The New York Times quoted George Maenchen as stating "All these claims are totally false.

The new concept used a fleet of about a hundred thousand small independent rockets weighing about 5 pounds (2.3 kg) each to destroy the missiles or warheads by colliding with them, no explosive required.

His works have generally ascribed the entire basis for SDI to Teller's overselling of the Excalibur concept, convincing Reagan a credible defensive system was only a few years away.

According to Broad, "Over the protests of colleagues, Teller misled the highest officials of the United States Government into the deadly folly known as Star Wars [the nickname for SDI].

Years later, Broad described the meeting this way: "For half an hour, Teller deployed X-ray lasers all over the Oval Office, reducing hundreds of incoming Soviet missiles to radioactive chaff, while Reagan, gazing up ecstatically, saw a crystal shield, covering the Last Hope of Man.

"[34] This basic telling of the story is recounted in other contemporary sources; in their biography, Edward Teller: Giant of The Golden Age of Physics, Blumberg and Panos essentially make the same statement,[96] as does Robert Park in his Voodoo Science.

[21] A Washington Post article by Patrick Tyler noted "Only Ronald Reagan could tell us if Edward Teller was the key influence on his decision to challenge American scientists to invent new defenses that would make nuclear weapons 'obsolete,' and so far the president isn't saying.

As long as there is a large population of atoms with electrons in the matching energy state, the result is a chain reaction that releases a burst of single-frequency, highly collimated light.

[104] The process of gaining and losing energy is normally random, so under typical conditions, a large group of atoms is unlikely to be in a suitable state for this reaction.

In the worst-case scenario, with the widest dispersion angle and the lowest enhancement, the pump weapon would have to be approximately 1 Mt for a single laser to deposit enough energy on the booster to be sure to destroy it at that range.

The only direct statement from one of the researchers was by Chapline, who described the medium on the original Diablo Hawk test being "an organic pith material" from a weed growing on a vacant lot in Walnut Creek, a town a short distance away from Livermore.

This was initially concerned with shooting down V-2-like targets, but an early study on the topic by Bell Labs suggested their short flight times would make it difficult to arrange an interception.

The same report noted that the longer flight times of long-range missiles made this task simpler, despite various technical difficulties due to higher speeds and altitudes.

It also led to the possibility of designing a bomb specifically to increase the X-ray release, which could be made so powerful the rapid deposit of energy on a metal surface would cause it to explosively vaporize.

For ICBMs launched from Kazakhstan, some 3,000 kilometers (1,900 mi) from the Arctic Ocean, the curvature of the Earth meant an Excalibur's laser beam would have a long path-length through the atmosphere.

Complicating the issue was that the rods needed to be as skinny as possible to focus the output, a concept known as geometric broadening, but doing so caused the diffraction limit to decrease, offsetting this improvement.

[133] In 1997 Russia deployed the Topol-M ICBM which utilized a higher-thrust engine burn following take-off, and flew a relatively flat ballistic trajectory, both characteristics intended to complicate space-based sensor acquisition and interception.

Chaney and Terry Maggert, the protagonist uses a secret U.S. defense satellite named "Amulet 2α", which is described as a "One-shot fission-pumped X-Ray laser", to destroy an attacking enemy spaceship.