The Star Trek Chicago '75 film premiered on YouTube, Feb 19 2010. Since then, It has been picked up by many Sci-fi related sites around the globe. "This convention was attended by the entire cast and may the reason for the video's popularity", says Rich Portnoy who filmed the event. "The fan response has been incredible", noting the barrage of comments on YouTube and personal emails, "One pointed out that David Gerrold, author of The Trouble with Tribbles, is the one kissing Nichelle Nichols". "I was also contacted by members of the The Dorsai Irregulars", Rich referring to the ones dressed like Klingons, "Turns out, they're a hardworking band of SciFi fans who [still to this day] provide operation support and crowd control for similar events." The number of views have now exceeded 22,000.
We wish to thank the following sites for making this video a success:
BroadBarn acquired this document from the Profiles in History auction house. It is a letter to Gene Roddenberry from a fan of the original Star Trek series. Gene thought enough of this letter to send it to Joe Jennings, Art Director of Star Trek, The Movie. For what may be the first time ever, the entire fan letter along with the note to Joe are being displayed to the public.
The Note to Joe from Gene is regarding a letter from an astute Star Trek fan. There appears to be enough clues in the fan's letter to Gene to pinpoint the time it was written. If anyone can decipher those clues, please suggest the date it was authored.
The note to Joe Jennings may have been sent sometime prior to the production of the first Star Trek Movie, for which Joe was the Art Director. The fan letter could have been written several years earlier.
OpenMinds UFO Headlines
Fri, 27 Jan 2012 14:21:42 +0000 13:52:51 EST -0500 Daily UFO Headlines 1/27/12
May 8th, 2011 02:21:54 EDT -0400 What made those tracks?
Last post I discussed how we reconstruct tracks in LHCb. The next logical step is to talk about how we identify what sort of particle left which track. Continuing with my analogy about animal tracking, animals leave very distinctive tracks related to their paw prints and how they move. You can basically tell what animal left a track by examining it carefully…
Unfortunately this is not possible with particle tracks. Only given the parameters of a reconstructed track, there is no way to determine what type of particle left that track. More information is required and that is where the RICH1 and RICH2 detectors come in.
The identity of a particle can be determined from its mass. The mass of a particle can be determined from its momentum and speed. The momentum of a charged particle is measured by its deflection in a magnetic field. The purpose of the RICH detectors is to match this information with a measurement of the particle’s speed.
RICH detectors work by measuring emissions of Cherenkov radiation. A charged particle traveling faster than the local speed of light in a medium emits Cherenkov radiation in the form of light, in a cone at an angle which depends on the speed of the particle. The RICH detectors focus the cone of Cherenkov light into a ring using mirrors onto an array of detectors. The radius of this ring provides information about the particle’s speed. Here are a few of the rings seen in RICH2 from an early LHC event.
The system of RICH detectors consists of an upstream detector (RICH1) which uses silica aerogel and \(C_{4}F_{10}\) gas as Cherenkov media located just behind the VELO, and a downstream detector (RICH2) using \(CF_{4}\) positioned after the magnet and tracking system. The use of silica aerogel allows the detector to identify low momentum particles (order of a few GeV), the use of \(C_{4}F_{10}\) allows the identification of higher momentum particles (between 10 GeV to around 65 GeV), while the use of \(CF_{4}\) allows the identification of even higher momentum particles (between 15 GeV to around 100 GeV).
Here is a schematic of the RICH1. Particles will enter the detector from the VELO on the left, then travel through the Cherenkov media, producing Cherenkov light which are reflected by the mirrors into the photon detectors. RICH2 is fairly similar.
The two RICH detectors are responsible for identifying a range of different particles that result from the decay of B mesons. Particle identification is crucial to reduce background in selected final states. For example, in the plots below, we are searching for the decay of a \(B_s\) meson into two \(K\) mesons. On the left, you can see that without the RICH it would be very hard to separate the signal, shown in red, from the backgrounds, since we would have no way of accurately differentiating \(K\) mesons from \(\phi\) mesons and \(\rho\) mesons. We would also have problems differentiating between \(B_s\) mesons and \(B_d\) mesons. On the right, using the RICH detectors, you can see that the signal is much much cleaner. They are very nice, useful detectors!
May 7th, 2011 02:21:54 EDT -0400 This just in! Congratulations!
http://blog.woodmarvels.com/
Congratulations goes out to fellow US LHC Blogger Prof. Sarah Demers for just being awarded the Department of Energy’s Early Career Award.  The announcement is naturally featured prominently on the website of her home institution, Yale University Physics Department.  This award has recently replaced the long-standing DOE Outstanding Junior Investigator Award (OJI), which has awarded grants to promising junior faculty members from 1978-2008, an impressive run!  The new Early Career award and has brought the previous National Science Foundation’s Early Career Award and DOE OJI awards together to a more similar format and award level.
These awards can mean a tremendous amount to a new faculty member in particle physics. I was fortunate enough to receive an OJI from the DOE, and fellow blogger Prof. Ken Bloom was fortunate to receive a Career Award from NSF, when we were both new junior professors. Â This allowed us both to support perhaps a graduate student and part of a postdoc’s salary as well as our own summer salaries while we established our research programs as new faculty members. Â Now Sarah has earned a peer-reviewed grant, which is a major milestone for a new professor, and which enables her to proceed with her successful research program without relying on university start-up funds (which eventually dry up). Â Here’s to Sarah’s future success!
CERN is the place to be if you’re a particle physicist! It has everything you could want here: the most promising experiments, all kinds of experts on hand, some of the most powerful computing systems in the world, fascinating seminars. It’s enough to draw people in from all over the world. The only downside is that it’s a bit tricky to get away from CERN for an evening in the city. Well not anymore! This week the tram arrived at CERN, giving us an essential lifeline to Geneva, with all its services and nightlife.
The CERN tram!
The town of Meryin saw the new tram as cause for a street party, with all kinds of entertainers, a jazz band, and free rides on an historic tram. So I went along to see what there was to offer, and how people reacted to the new transport link. Everyone seemed to be very happy about it (except perhaps for a few motorists!) “Great!” I thought, this gives us an easy way to get around. We can socialize more often, making it easier to meet people, enjoy ourselves, and making short trips to CERN all the more fun. There are many people who come to CERN for a few weeks or months at a time over the summer, and there’s pressure to cram as much into their time here as possible. Trimming some minutes off the journeys to and from Geneva makes things just that little bit easier for everyone!
People coming to explore CERN
What impressed me most was how CERN used this opportunity to reach out the public. In retrospect it was silly that I didn’t realize the tram went to CERN as well as from CERN! The new service included a tram advertizing CERN, taking people right up the Microcosm and the Globe, where they were welcomed in to see what CERN has to offer. Presumably this is only the start of a new way of approaching CERN (literally and figuratively.) This is the first time people can get directly from the heart of Geneva to the center of CERN’s public spaces. The icing on the cake is the tram itself, which is so modern and spacious. First impressions matter, and no longer relying on the rickety number 56 bus to go the final mile will make a big difference to people’s perceptions of CERN. It’s a place which is modern, relevant, well connected and a vital part of the greater Geneva area. It’s deserved a tram stop for years and one has finally arrived!
more...
May 5th, 2011 02:21:54 EDT -0400 A diagrammatic hint of masses from the Higgs
We learned that the Higgs is a different kind of particle from the usual gauge boson “force” particles or the fermion “matter” particles: it’s a scalar particle which, for those who want to be sophisticated, means that it carries no intrinsic quantum mechanical spin. Practically for these posts, it means that we ended up drawing the Higgs as a dashed line. For the most part, however, the Feynman rules that we presented in the previous post were pretty boring…
Recall the big picture for how to draw Feynman diagrams:
Different particles are represented by lines. We now have three kinds: fermions (solid lines with arrows), gauge bosons (wiggly lines), and scalars (dashed lines).
When these particles interact, their lines intersect. The “rules” above tell us what kinds of intersections are allowed.
If we want to figure out whether a process is possible, we have to decide whether or not we can use the rules to convert the initial set of particles into the final set of particles.
If you’ve been following our posts on Feynman diagrams, then you might already be bored of this process. We could see how electrons could turn into muons, or even how the Higgs boson might be produced at the LHC; but now we’ve arrived at the Higgs boson—one of the main goals of the LHC—where is the pizzazz? What makes it special, and how do we see it in our Feynman rules?
The Higgs is special
It turns out that the Higgs has a trick up it’s sleeve that the other particles in the Standard Model do not. In the language of Feynman diagrams, a Higgs line can terminate:
The “x” means that the line just ends; there are no other particles coming out. Very peculiar! We know that ordinary particles don’t do this… we don’t see matter particles disappearing into nothing, nor do we see force particles disappearing without being absorbed by other particles. We can think about what happens when matter and anti-matter annihilate, but there we usually release energy in the form of force particles (usually photons). The above rule tells us that a single Higgs line—happily doing its own thing—can be suddenly be cut off. It shouldn’t be read as an initial state or final state particle. It’s just some intermediate line which happens to stop.
We’ll discuss the physical meaning of this in upcoming posts. Sometimes when people try to explain the physical meaning they can get caught up in their own analogies. Instead, let us use the Feynman diagrams as a crutch to see the effects of this weird Feynman rule. Recall that in the previous post we introduced a four-point Higgs self-interaction (“four-point” means four Higgs lines intersecting):
If we take one of the lines and terminate it, we end up with a three-point Higgs self interaction:
In fact, since the crossed out line isn’t doing anything, we might as well say that there is a new Feynman rule of the form
Now that’s somewhat interesting. We could have forgotten about the “crossed out Higgs line” rule and just postulated a three-point vertex. In fact, usually this is the way people write out Feynman rules (this is why our method has been “idiosyncratic“); however, for our particular purposes it’s important to emphasize that what people really mean is that there is implicitly a “crossed out Higgs line.” The significance is closely tied up to what makes the Higgs so special.
We could play this game again and cross one one of these three lines. This would lead us to a two-point Higgs interaction.
Once again, we could just as well chop off the two terminated lines and say that there is a ‘new’ two-point Higgs Feynman rule. But this is really just a line, and we already knew that we could draw lines as part of our Feynman rules. In fact, we know that that lines just mean that a particle moves from one place to another. So it seems like this interaction with two crossed out lines doesn’t give us anything news.
… except there’s more to it, and this is where we start to get a hint of the magic associated with the Higgs. Let me make the following statement without motivation:
Claim: the above Feynman rule is a contribution to the Higgs mass.
At this point, you should say something incredulous like, “Whaaaaaat?” Until now, we’ve said that particles have some particular mass. The number never really mattered that much, some particles are lighter than others, some particles have zero mass. Mass is just another property that each particle seems to have. Now, however, we’ve made a rather deep statement that puts us at the tip of a rather large iceberg: we’re now relating a particular Feynman rule to the mass of the particle, which we had previously assumed was just some number that we had to specify with our theory.
We’ll have to wait until my next post to really get into why such a relation should exist and really what we even mean by mass, but this should at least start to lend credence to the idea that the Higgs boson can give masses to particles. At this point this should still feel very mysterious and somewhat unsatisfying—that’s okay! We’ll get there. For now, I just want you to feel comfortable with the following string of ideas:
The Higgs boson has a special Feynman rule where a line can terminate.
This means we can take any interaction and effectively remove the Higgs line by terminating it immediately after the vertex.
In particular, this means that we generate a vertex with just two lines.
This vertex with two lines should—for reasons which are presently mysterious—be identified with mass.
Giving mass to the other particles
Now that we see how this game works, we should immediately go back to the first two Feynman rules we wrote down:
These are the interactions of the Higgs with fermions and gauge bosons. Here’s what you should be thinking:
Hm… I know that the Higgs boson line can terminate; I can just cross out the end points of a dashed line. And I just saw that when I do this to the Higgs self-interaction vertex enough times, I end up with a two-point interaction which Flip tells me is a mass for some weird reason. Now I these two vertexes representing the Higgs interaction with two matter particles or two force particles. Does terminating the Higgs line also give mass to these particles?
The answer is yes! We end up with vertices like this:
For aesthetic reasons (and really only for aesthetic reasons) we can shrink this diagram to:
We can even drop the “x” if you want to be even more of a purist… but for clarity we’ll leave it here to distinguish this from a normal line. These diagrams indeed represent a mass contribution to fermions and gauge bosons. Again, I’m just telling you this as a mysterious fact—we’ll explain why this interpretation is accurate later on. We’ll need to first understand what “mass” really is… and that will require some care.
Bumping up against the Higgs
In fact, instead of saying that particles “start out” with any masses, one can formulate our entire Feynman diagram program in terms of completely massless particles. In such a picture, particles like the top quark or Z boson undergo lots of the aforementioned two-point “mass” interactions and so are observed to have larger masses. Heuristically, heavy particles barrel along and have lots of these two-point interactions:
For comparison, a light particle like the electron would have fewer of these interactions. Their motion (again, heuristically) looks more like this:
We should remember that each of these crosses is really a terminated Higgs line. To use some fancy parlance which will come up in a later post, we say that the Higgs has a “vacuum expectation value” and that these particles are bumping up against it. The above pictures are just ‘cartoons’ of Feynman diagrams, but you can see how this seems to convey a sense of “inertia.” More massive particles (like the top quark) are harder to push around because they keep bumping up against the Higgs. Light particles, like the electron, don’t interact with the Higgs so much and so can be pushed more easily.
In this sense, we can think of all particles as being massless, but their interactions with the Higgs generates a two-point interaction which is effectively a mass. Particles which interact more strongly with the Higgs have more mass, while particles which interact weakly with the Higgs have less mass. In fact, once we assume this, we might as well drop all of the silly crosses on these lines—and then we’re left with the usual Feynman rules (with no terminating Higgs lines) that are usually presented.
(A small technical note: the Higgs isn’t actually responsible for all mass. For example, bound states get masses from their binding energy. Just look up the mass of the proton and compare it to the mass of its constituent quarks. The proton has a mass of about 1 GeV, while the up/down quarks are only one thousandth of this. Most of the proton mass comes from the binding energy of QCD.)
Some closing remarks
Before letting you ponder these things a bit more, let me make a few final remarks to whet your appetite for our next discussion.
The photon, as we know, is massless. We thus expect that the Higgs does not interact with the photon, or else we could have ‘terminated’ the Higgs lines in the interaction vertex and generated a photon mass.
On the other hand, the Higgs gives the W and Z bosons mass. This means that it costs energy to produce these guys and so the weak is only really effective over a short distance. Compare this to photons, which are massless, and so can produce a long range force. (Gluons are also massless, but they have a short range force due to their confinement.) Thus the Higgs is responsible for the “weakness” of the weak force.
… on that note, it’s worth noting that the “weak” force isn’t really so weak—it only appears weak at long distances due to the mass of the W and Z. If you look at shorter distances—say on distances shorter than the distance between two Higgs crosses in the cartoon picture above—then you’d find that the weak force is actually quite potent compared to electromagnetism. Thus a more accurate statement is that the Higgs is responsible for the short-ranged-ness of the weak force.
There are also a few open questions that are worth pointing out at this point. We’ll try to wrap these up in the upcoming posts on this subject.
The big elephant in the room is the question of why the two-point interaction from terminating a Higgs line should be interpreted as a mass. We got a hint in the picture above of how “bumping off the Higgs” can at least heuristically appear to have something to do with inertia. We’d like to better understand what we really mean by mass.
We also very glibly talked about treating everything as massless and only generating ‘effective’ masses through such Higgs interactions. Special relativity tells us that there is a very big difference between a particle with exactly no mass and those with some mass… this has to do with whether or not it is possible in principle to catch up to a particle. How does this mesh with our picture above that masses can come from ‘bumping off the Higgs?”
What does it mean physically that the Higgs line can terminate? What do we mean by the “vacuum expectation value?” This will turn out to be related to the idea that all of our particles are manifested as quantum fields. What does this mean?
This whole business is related to something called electroweak symmetry breaking, and that is the phenomenon associated with the Higgs which is really, really magical.
January 27th, 2012 02:44:58 EST -0500 Iggy (Southern Indian Ocean)
NASA satellites are providing valuable data to forecasters as Tropical Cyclone Iggy nears Western Australia. more...
January 27th, 2012 02:44:58 EST -0500 Funso (Southern Indian Ocean)
Powerful Cyclone Funso's eye has been clear in NASA satellite imagery over the last several days until NASA's Aqua satellite noticed it had "closed" and become filled with high clouds on January 27. more...
January 23rd, 2012 02:44:58 EST -0500 Ethel (Southern Indian Ocean)
Infrared imagery from NASA's Aqua satellite revealed an area of strong convection and strong thunderstorms around the center of Tropical Storm Ethel, even as the storm continues to weaken and become extratropical. more...
January 28th, 2012 02:44:58 EST -0500 NASA Hurricane Updates on Twitter
Check NASA's Hurricane Twitter feed for a daily behind the scenes look at storms in the tropics. more...
January 28th, 2012 02:44:58 EST -0500 NASA Hurricane Updates on Facebook
Check NASA's Hurricane on Facebook provides daily looks at storms in the tropics and it's updated on Weekends during storms more...
NASA News
January 27th, 2012 02:44:58 EST -0500 NASA's J-2X Engine Kicks Off 2012 With Powerpack Testing A new series of tests on the engine that will help carry humans to deep space will begin next week at NASA’s Stennis Space Center in southern Mississippi. The tests on the J-2X engine bring NASA one step closer to the first human-rated liquid oxygen and liquid hydrogen rocket engine to be developed in 40 years. more...
January 27th, 2012 02:44:58 EST -0500 Texas Students to Speak Live With Space Station Crew Fifth- through eighth-grade students at Asa Low Intermediate School in Mansfield, Texas, will speak with NASA’s Expedition 30 Commander Dan Burbank and Flight Engineer Don Pettit aboard the International Space Station at 11:50 a.m. EST on Tuesday, Jan. 31. more...
January 27th, 2012 02:44:58 EST -0500 Astronaut Jerry Ross, First Seven-Time Flier, Retires Jerry Ross, the first person to launch into space seven times, has retired from NASA. In a career that spanned more than three decades, Ross spent almost 1,400 hours in space and conducted nine spacewalks to rank third on the list of most extravehicular activity time in space. more...
January 26th, 2012 02:44:58 EST -0500 NASA Awards Safety And Mission Assurance Contract Extension NASA has exercised two six-month options to the agency's Safety and Mission Assurance Support Services Contract with Science Applications International Corp. (SAIC) of San Diego for the Johnson Space Center in Houston. The options are worth $32.9 million. more...
January 26th, 2012 02:44:58 EST -0500 NASA's Kepler Announces 11 Planetary Systems Hosting 26 Planets NASA's Kepler mission has discovered 11 new planetary systems hosting 26 confirmed planets. These discoveries nearly double the number of verified planets and triple the number of stars known to have more than one planet that transits, or passes in front of, the star. more...
NASA pic of the day
Fri, 27 Jan 2012 00:00:00 EST Cloud streets off of the Aleutian Islands
Strong winds polished the snow of southwestern Alaska and stretched marine stratocumulus clouds into long, parallel streets in early January, 2012. After crossing Bristol Bay, the winds scraped the clouds across the tall volcanic peaks of the Aleutian Islands. As the wind impacted the immobile mountains, the airflow became turbulent, swirling in symmetric eddies and carving intricate patterns into the clouds on the leeward side of the islands. At the top of this image, the bright white color indicates a thick layer of snow overlying the land of southwestern Alaska. The pristine white is broken by the rugged Ahklun Mountain Range in the east, which is partially covered by a bank of clouds. Off the coast of Alaska, sea ice floats in Bristol Bay, cracked and chipped by the flow of the waters which lie underneath. A few cloud streets – parallel lines of clouds – can be seen in the far northwest over land. The clouds increase over the sea ice and become thick over open water, where row upon row of clouds lie close in perfectly parallel formation. The Aleutian Islands stretch from northeast to southwest across the image. Sea ice, which is bright white here, lies on the windward side of the islands. A few of the tallest volcanic peaks can be seen rising from the icy islands. The character of the cloud streets change as they impact the Aleutians, especially near the center of the image, where two rows of beautifully symmetric swirls of eddies in the clouds stretch across the sky. These swirling formations are known as von Karman vortex streets. This true-color image was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite on January 11, 2012. Image Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team
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