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"Hbar Technologies plans a Kickstarter effort to raise US $200,000 for the next phase design of an antimatter-propelled spaceship. The two scientists behind this design effort are a veteran Fermilab particle accelerator scientist and a former Los Alamos National Laboratory physicist and founding director of the U.S. Center for Space Nuclear Research. They originally developed it for NASA at the turn of the millennium."

The ALPHA collaboration reports the first ever measurement on the optical spectrum of an antimatter hydrogen atom. Optical transitions shown to be the same as for normal hydrogen. Paper at http://www.nature.com/nature/journal/vaap/ncurrent/full/nature21040.html#affil-auth

Small scale laser induced electron accelerator followed by induced beta decay to produce positrons. Relatively simple, yet requires a high power fs laser and some precision engineering

Latest simulation shows that the magnetic nozzles required for antimatter propulsion could be vastly more efficient than previously thought--and built with today's technologies

more antimatter ...

Physicists working on the LHCb experiment at the CERN particle-physics lab have released the best evidence yet for direct charge-parity (CP) violation in charm mesons....While more data must be analysed to confirm the result, the work could point to new physics beyond the Standard Model and help physicists understand why there is more matter than antimatter in the universe.

lot of new physics this year ...

The ASACUSA experiment at CERN has succeeded for the first time in producing a beam of antihydrogen atoms. The ASACUSA collaboration reports the unambiguous detection of 80 antihydrogen atoms 2.7 metres downstream of their production, where the perturbing influence of the magnetic fields used initially to produce the antiatoms is small. http://www.nature.com/ncomms/2014/140121/ncomms4089/full/ncomms4089.html

antihydrogen propulsion...?

didn't roger write an assessment of antimatter propulsion when he was in the ACT?

yeah the problem is the amount of antimatter you can get and more specifically how to trap it. I found that you would need around one gram to go to the outer Solar System. So we are far from that, but finding an efficient way to trap it, with an electromagnetic trap rather than solid walls is a first step !

Not really the first time, but they seem to be much closer to be being able to study them. Apparently, they had 38 atoms trapped for miliseconds. Now it's time to prove it behaves just like matter.

Theorists expect that positronium, a sort of 'atom' consisting of an electron and an anti-electron, can be used to make a powerful gamma-ray laser. Scientists now report detailed calculations of the dynamics of a positronium BEC. This work is the first to account for effects of collisions between different positronium species.

Interesting... however to me it looks like they have only shifted the problem... instead of looking for WIMPS now we look for X and Y and Phi...

An exhaustive overview of all possible advanced rocket concepts, eg.. "As an example, consider a photon rocket with its launching mass, say, 1000 ton moving with a constant acceleration a =0.1 g=0.98 m/s2. The flux of photons with E γ=0.5 MeV needed to produce this acceleration is ~1027/s, which corresponds to the efflux power of 1014 W and the rate of annihilation events N'a~5×1026 s−1 [47]. This annihilation rate in ambiplasma l -l ann corresponds to the value of current ~108 A and linear density N ~2×1018 m−1 thus any hope for non-relativistic relative velocity of electrons and positrons in ambiplasma is groundless." And also, even if it would work, then one of the major issues is going to be heat dispersal: "For example, if the temperature of radiator is chosen T=1500 K, the emitting area should be not less than 1000 m2 for Pb=1 GW, not less than 1 km2 for Pb=1 TW, and ~100 km2 for Pb=100 TW, assuming ε=0.5 and δ=0.2. Lower temperature would require even larger radiator area to maintain the outer temperature of the engine section stable for a given thermal power of the reactor."

The problem is not achieving a high energy density, that we can already do with nuclear fission, the question however is how to confine or harness this power with relatively high efficiency, low waste heat and at not too crazy specific mass. I see magnetic confinement as a possibility, yet still decades away and also an all-or-nothing method as we cannot easily scale this up from a test experiment to a full-scale system. It might be possible to extract power from such a plasma, but definitely well below breakeven so an additional power supply is needed. The fission fragments circumvent these issues by a more brute force approach, thereby wasting a lot of energy for sure but at the end probably providing more ISP and thrust.

Sure. However, the annihilation based photon rocket concept unifies almost all relevant drawbacks if we speak about solar system scales, making itself obsolete...it is just an academic testcase.