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...leaving the world far less capable of observing the next supernova neutrino burst, should it arrive before repairs or a replacement could be completed.

While the accident is a tragic blow to some valid and interesting research, no one should lose any sleep over the possibility of being unable to analyze the next big supernova before it can be repaired. After all, supernovae on the scale of SN1987A occur once every few hundred years (the last two occurred in 1054 and 1572.) I suspect repairing Super-K will take significantly faster than that.

Even in the minuscule chance that a big supernova will occur in the meantime, Super-K isn't the only neutrino observatory around. The Sudsbury Neutrino Observatory, a similar experiment, is online and producing some very good results.

At this energy, IceCube is then sensitive to all three types of neutrinos (e, mu, and tau); SNO can only see the first two, because the tau lepton (that the neutrino has to turn into to be detected) is so huge it's way outside SNO's energy range.

I know that SNO has about 9600 phototubes, and IceCube has about 5000, so SNO might be a bit more accurate for this reason.

Besides that, IceCube is huge. SNO is a sphere 12 metres across, or just under 2000 cubic metres. IceCube is a cubic kilometer, or 1000000 cubic metres. So it'll see a whole lot more neutrinos! (This may be related to why IceCube has a higher energy range.)

The Sudbury Neutrino Observatory ( SNO) is taking data that has provided revolutionary insight into the properties of neutrinos and the core of the sun. The detector, shown in the artist's conception below, was built 6800 feet under ground, in INCO's Creighton mine near Sudbury, Ontario. SNO is a heavy-water Cherenkov detector that is designed to detect neutrinos produced by fusion reactions in the sun. It uses 1000 tonnes of heavy water, on loan from Atomic Energy of Canada Limited (AECL), contained in a 12 meter diameter acrylic vessel. Neutrinos react with the heavy water (D2O) to produce flashes of light called Cherenkov radiation. This light is then detected by an array of 9600 photomultiplier tubes mounted on a geodesic support structure surrounding the heavy water vessel. The detector is immersed in light (normal) water within a 30 meter barrel-shaped cavity (the size of a 10 story building!) excavated from Norite rock. Located in the deepest part of the mine, the overburden of rock shields the detector from cosmic rays. The detector laboratory is extremely clean to reduce background signals from radioactive elements present in the mine dust which would otherwise hide the very weak signal from neutrinos.

The Sudbury Neutrino Observatory ( SNO) is taking data that has provided revolutionary insight into the properties of neutrinos and the core of the sun. The detector, shown in the artist's conception below, was built 6800 feet under ground, in INCO's Creighton mine near Sudbury, Ontario. SNO is a heavy-water Cherenkov detector that is designed to detect neutrinos produced by fusion reactions in the sun. It uses 1000 tonnes of heavy water, on loan from Atomic Energy of Canada Limited (AECL), contained in a 12 meter diameter acrylic vessel. Neutrinos react with the heavy water (D2O) to produce flashes of light called Cherenkov radiation. This light is then detected by an array of 9600 photomultiplier tubes mounted on a geodesic support structure surrounding the heavy water vessel. The detector is immersed in light (normal) water within a 30 meter barrel-shaped cavity (the size of a 10 story building!) excavated from Norite rock. Located in the deepest part of the mine, the overburden of rock shields the detector from cosmic rays. The detector laboratory is extremely clean to reduce background signals from radioactive elements present in the mine dust which would otherwise hide the very weak signal from neutrinos.

The Sudbury Neutrino Observatory ( SNO) is taking data that has provided revolutionary insight into the properties of neutrinos and the core of the sun. The detector, shown in the artist's conception below, was built 6800 feet under ground, in INCO's Creighton mine near Sudbury, Ontario. SNO is a heavy-water Cherenkov detector that is designed to detect neutrinos produced by fusion reactions in the sun. It uses 1000 tonnes of heavy water, on loan from Atomic Energy of Canada Limited (AECL), contained in a 12 meter diameter acrylic vessel. Neutrinos react with the heavy water (D2O) to produce flashes of light called Cherenkov radiation. This light is then detected by an array of 9600 photomultiplier tubes mounted on a geodesic support structure surrounding the heavy water vessel. The detector is immersed in light (normal) water within a 30 meter barrel-shaped cavity (the size of a 10 story building!) excavated from Norite rock. Located in the deepest part of the mine, the overburden of rock shields the detector from cosmic rays. The detector laboratory is extremely clean to reduce background signals from radioactive elements present in the mine dust which would otherwise hide the very weak signal from neutrinos.

The Sudbury Neutrino Observatory ( SNO) is taking data that has provided revolutionary insight into the properties of neutrinos and the core of the sun. The detector, shown in the artist's conception below, was built 6800 feet under ground, in INCO's Creighton mine near Sudbury, Ontario. SNO is a heavy-water Cherenkov detector that is designed to detect neutrinos produced by fusion reactions in the sun. It uses 1000 tonnes of heavy water, on loan from Atomic Energy of Canada Limited (AECL), contained in a 12 meter diameter acrylic vessel. Neutrinos react with the heavy water (D2O) to produce flashes of light called Cherenkov radiation. This light is then detected by an array of 9600 photomultiplier tubes mounted on a geodesic support structure surrounding the heavy water vessel. The detector is immersed in light (normal) water within a 30 meter barrel-shaped cavity (the size of a 10 story building!) excavated from Norite rock. Located in the deepest part of the mine, the overburden of rock shields the detector from cosmic rays. The detector laboratory is extremely clean to reduce background signals from radioactive elements present in the mine dust which would otherwise hide the very weak signal from neutrinos.

The Sudbury Neutrino Observatory ( SNO) is taking data that has provided revolutionary insight into the properties of neutrinos and the core of the sun. The detector, shown in the artist's conception below, was built 6800 feet under ground, in INCO's Creighton mine near Sudbury, Ontario. SNO is a heavy-water Cherenkov detector that is designed to detect neutrinos produced by fusion reactions in the sun. It uses 1000 tonnes of heavy water, on loan from Atomic Energy of Canada Limited (AECL), contained in a 12 meter diameter acrylic vessel. Neutrinos react with the heavy water (D2O) to produce flashes of light called Cherenkov radiation. This light is then detected by an array of 9600 photomultiplier tubes mounted on a geodesic support structure surrounding the heavy water vessel. The detector is immersed in light (normal) water within a 30 meter barrel-shaped cavity (the size of a 10 story building!) excavated from Norite rock. Located in the deepest part of the mine, the overburden of rock shields the detector from cosmic rays. The detector laboratory is extremely clean to reduce background signals from radioactive elements present in the mine dust which would otherwise hide the very weak signal from neutrinos.

The Sudbury Neutrino Observatory ( SNO) is taking data that has provided revolutionary insight into the properties of neutrinos and the core of the sun. The detector, shown in the artist's conception below, was built 6800 feet under ground, in INCO's Creighton mine near Sudbury, Ontario. SNO is a heavy-water Cherenkov detector that is designed to detect neutrinos produced by fusion reactions in the sun. It uses 1000 tonnes of heavy water, on loan from Atomic Energy of Canada Limited (AECL), contained in a 12 meter diameter acrylic vessel. Neutrinos react with the heavy water (D2O) to produce flashes of light called Cherenkov radiation. This light is then detected by an array of 9600 photomultiplier tubes mounted on a geodesic support structure surrounding the heavy water vessel. The detector is immersed in light (normal) water within a 30 meter barrel-shaped cavity (the size of a 10 story building!) excavated from Norite rock. Located in the deepest part of the mine, the overburden of rock shields the detector from cosmic rays. The detector laboratory is extremely clean to reduce background signals from radioactive elements present in the mine dust which would otherwise hide the very weak signal from neutrinos.

Moderators, that was most certainly *not* offtopic.

I would be very much interested in a comparison between the Ice Cube and SNO. My guess is that the Ice Cube is a lot cheaper, but that the SNO is a lot more accurate.

• In June we got the news from the Sudbury Neutrino Oscilloscope that from the detection rates of muon-type and electron-type neutrino's coming from the Sun we should conclude that neutrinos oscillate (change type) and are therefore massive, which is in full contradiction with the SM.
• In March this year the results of the 1999 data of the muon g-2 measurement at Brookhaven National Laboratory showed that the (anomalous) magnetic moment of the muon is not described correctly by the SM. This 'magnetic moment' indicates how much the spin of a muon is affected by a magnetic field (a bit like how quickly a compass needle reacts to a new orientation of the compass). This measurement generated lots of theoretical ideas for mods of the SM and/or signs of supersymmetry and what not.
• The Standard Model is ugly.

So is SNO

To explain the discrepancy between their very precise findings and their expectations, NuTeV experimenters wonder if their neutrinos have felt a new force previously unobserved in nature, or if there is some hitherto undiscovered particle influencing neutrino interactions.

It seems like there a whole bunch of weird shi^H^Htuff going on with Neutrinos. The Sudbury experiment this summer is starting to show non-zero neutrino mass, which I understood meant that oscillation between states was going to not happer - or be severely limited.

Now this experiment seems to show that not only is oscillation possibly happening but at a slightly greater rate than we expect.

Admittedly these are completely different effects - and on the surface aren't related but...

I agree with the quote above - my "spidey sense" is making me think that something really interesting is going on with Neutrinos, and perhaps the elementary particle types should start really focusing on getting some better data...

You know - there are going to be a number of vacant deep mine shafts coming vacant in Afgahnistan soon...

While they have a standard webpage, the engineering society also managed to snag the quite sought-after www.campusbookstore.com domain name. Not bad, huh?

Really ugly Replica document I created in 1993.

Yes, well done Queen's. You may have your solar car, since we all know that U of T is the best school in Canada, nay, the Universe. Who names a school "Queen's", anyway?

• Being recognized by the Guinness Book of World Records for "Furthest distance traveled by a solar car in one journey", referring to their 7044 km trans continental drive completed last summer
• Top North American finisher in 1997 and 1999 at the World Solar Challenge in Australia, placing second in the world in 1999, losing to a non-university team
• Second place last year at Sunrayce (The previous incarnation of the American Solar Challenge)

Please, check out their website! Remember, ( Not Iowa State ).

• Being recognized by the Guinness Book of World Records for "Furthest distance traveled by a solar car in one journey", referring to their 7044 km trans continental drive completed last summer
• Top North American finisher in 1997 and 1999 at the World Solar Challenge in Australia, placing second in the world in 1999, losing to a non-university team
• Second place last year at Sunrayce (The previous incarnation of the American Solar Challenge)

Please, check out their website! Remember, ( Not Iowa State ).

• Being recognized by the Guinness Book of World Records for "Furthest distance traveled by a solar car in one journey", referring to their 7044 km trans continental drive completed last summer
• Top North American finisher in 1997 and 1999 at the World Solar Challenge in Australia, placing second in the world in 1999, losing to a non-university team
• Second place last year at Sunrayce (The previous incarnation of the American Solar Challenge)

Please, check out their website! Remember, ( Not Iowa State ).

• Being recognized by the Guinness Book of World Records for "Furthest distance traveled by a solar car in one journey", referring to their 7044 km trans continental drive completed last summer
• Top North American finisher in 1997 and 1999 at the World Solar Challenge in Australia, placing second in the world in 1999, losing to a non-university team
• Second place last year at Sunrayce (The previous incarnation of the American Solar Challenge)

Please, check out their website! Remember, ( Not Iowa State ).

• Being recognized by the Guinness Book of World Records for "Furthest distance traveled by a solar car in one journey", referring to their 7044 km trans continental drive completed last summer
• Top North American finisher in 1997 and 1999 at the World Solar Challenge in Australia, placing second in the world in 1999, losing to a non-university team
• Second place last year at Sunrayce (The previous incarnation of the American Solar Challenge)

Please, check out their website! Remember, ( Not Iowa State ).

It's even more complicated than this. There are two kinds of mass people talk about in connection with neutrinos: Dirac mass and Majorana mass. Dirac mass is the same kind of thing as the conventional rest mass of other particles. Majorana mass is tied together with the helicity of the particle: left handed neutrinos and right handed antineutrinos are one and the same, more or less.

All this is off the top of my head, I'm no longer in the business nowadays.

For further reference, here's an article at physicscentral.com relating to the experiment. It does not give much more details on the technical aspects of the mass, though. And here's the SNO press release off of their homepage.

The Sudbury Neutrino Observatory homepage has their own article about the results. The full paper that they submitted to Physical Review Letters is also avilable online.

-Erf C.

The Sudbury Neutrino Observatory homepage has their own article about the results. The full paper that they submitted to Physical Review Letters is also avilable online.

-Erf C.

The Sudbury Neutrino Observatory homepage has their own article about the results. The full paper that they submitted to Physical Review Letters is also avilable online.

-Erf C.

Swedish Chef translator here!!!!

MicroImages MI/X used to be free, but they're charging $25 for the latest version. A hunt around the web should turn up the earlier version on a few ftp sites. For example, I found it here.

..that looks like unix :)

Some interesting software behind this thing, too.

Just for the record, SNO isn't so near Kingston. It's near Sudbury (it is, after all, the Sudbury Neutrino Observatory), which is probably a 6 hour drive from Kingston. Queen's University in Kingston is the "home" of the project in spirit (and administration) only.

It is a cool project, just the same.

The "Myo-Electric Locust" (MEL) is presumably named after his academic supervisor, Dr. Mel Robertson. Their lab studies the neural control of insect flight using locusts as a model. IANAE(xpert) but it seems like this sort of thing would be of interest to the automation and robotics community.

Since no one else is posting any sites to find info... here goes.

Yahoo! People Search
FAQ: How to find people's E-mail addresses
Yahoo! People Search
InfoSpace
ICQ Search
BigYellow.com

...and this is just the tip of the iceberg. Try a search on deja.com for your name, you might be surprised.

When the occassional neutrino interacts with a water molecule, they use calorimetry to measure its energy and thus deduce its mass. Now if this sounds like a very imprecise measurement method, it is.

That would be pretty imprecise, given that you're dealing with abandoned mines filled with water or the Pacific ocean. Is that really how they do it, though? I know neutrino detection is typically done by light sensor arrays picking up Cerenkov radiation from neutrinos hitting the water (example). Maybe the mass is calculated differently, though.

Sudbury Neutrino Observatory

This detector is designed to answer the "solar neutrino problem", namely that we keep detecting half as many neutrinos as we should be from the sun. Where did the other half go? One theory is that neutrinos oscillate between types. I.e. a muon neutrino oscillates into a tau neutrino as it travels to the earth. The new form of neutrino is then not detected because the original detectors only detected muon neutrinos. SNO will be able to detect both types and distinguish between them, so it should be able to convincingly answer the question of the missing neutrinos.

nojw

Tracksuit, the band I'm in at Queen's University has covered bits of Mega Man in Fortunate Son by CCR. We're certainly not the first too. Lots of bands will jump into old classics like that because everyone in College/University is at that 'perfect' age to have been a kid when the NES came out. I can't tell you how many people recognize the SMB2 *bass line*!

From data on nucleosynthesis (thermonuclear reaction hydrogen-> deuterium, tritium, helium, lithium and a little bit of other stuff) and from recent Boomerang data we know that most of the mass in Universe is not in hydrogen or other baryonic matter. It is a simple argument, actually. If density of gas is high, thermonuclear reactions would go much faster and isotopes that are fast to be consumed (deutherium, Helium3) would not survive to our time. But there exist deuterium and other fast burning isotopes in interstellar gas. Therefore, there were not enough gas to account for all mass in the Universe. See this link for details. There is other evidence as well for dark matter that is not hydrogen or other baryonic gas. Hey, I wrote it right this time --- baryons ;-)

I've heard an unverified rumour of a prank like this. Unfortunately this didn't go nearly as well. Guys from the all-male dorm called Leonard at my University (Queen's) snuck a cow high up into an all girl's dorm McNeill.

Unfortunately getting the cow out wasn't as easy. The halls and stairways were very narrow so the cow couldn't be turned around. The cow would not back down the stairs, and there was no other way to get it out. So unfortunately the cow had to be killed and butchered inside the dorm and brought down in pieces.

Oh well, most of the other pranks worked much better.

In my MBA program (Queen's MBA for Science & Technology) which is Canadian, eh, this is relatively common. Most of our exams are "open laptop" which means you can utilize the laptop for problem solving. Of those exams, most of the 'case' exams are "open Internet". (We are allowed to plug in the Ethernet cables) The deliverables are usually transferred to the professor by email, or simply printed and handed in.

This has worked great so far. Laptops are mandatory anyway (will be included in tuition starting next year, I believe), but I realize there is a significant difference between an MBA and an undergraduate degree. My point is, when all students are on a roughly equal technological platform, both in terms of possessing the same technology, and being able to use it, I believe computer based exams are fair, powerful and closer to a "real life" situation. We are testing the ability to utilize resources (similar to what is available in real life) and analyze a problem, then suggest recommendations within the time constraints.

One problem that was brought up was the possibility for cheating. On 'case analysis' type exams, cheating is relatively hard to do. Besides, in a small group the honour system does work fairly well. I have never heard of anybody cheating on an exam, or even planning to do so.

On many exams, however, a laptop is simply not a meaningful way of testing knowledge/learning. And that's why my good ol' pencil still has chew marks on it.

Likewise for my alma mater, Queen's University at Kingston. Queen's has had network ports in the residences for four years now - maybe five, but I think four. A friend of mine ran the program during those early years.

This inevitably causes problems, of course, with shared resources, such as QLink (the student unix server - 16k accounts on one box). And it causes intermittent network degradation, although not as much as you'd think.

--

How is the living space though? Commuting in from a nice little town just outside of Toronto is what I'm aiming for, mainly because it can get pretty crowded in the city itself..

Turgidson:

Doctor, you mentioned the ration of ten women to each man. Now, wouldn't that necessitate the abandonment of the so called monogamous sexual relationship, I mean, as far as men were concerned?

Strangelove:

Regrettably, yes. But it is, you know, a sacrifice required for the future of the human race. I hasten to add that since each man will be required to do prodigious... service along these lines, the women will have to be selected for their sexual characteristics which will have to be of a highly stimulating nature.

The Sudbury Neutrino Observatory is a similar project - a sphere of heavy-water buried 2km underground.

Following a thread of thought from this piece, have a look at how animal behaviour is being used in, among other things, satellite attitude control systems.

(Aside: I met Mark Tilden back in first year at a talk he gave about his analog approach to robot design. He talks klicks-a-minute, but it's worth every second.)