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As I said in my previous post ... "things still need a bit of fussing."

Currently having beam quality problems on injection (chroma problems).

Beams up - Ramp is Coming!!!!!!!!!!!

From P1:
Both beams injected ... and locking better. we now correct and then we should ramp

Hi - new to the forum and in Australia, so I look at things when most of you are in bed.....

You just missed another record - 3.5TeV on both beams for about 2 hours or so from around 3am (they just shut down the beams so I have lost the graphs). Graphs looked very pretty - nice clean lines right on top of each other for both beams.

Bring it on!

There was a trip just as they reached 3.5TeV/beam and so the beams were dumped. Up to that point, though, everything looked great, and the intensities of both beams were very steady.

Since both beams were running, does that mean that they collided at any point?

Probably rather no collissions until now. Evenso the beams always intersect at the collission points it is very unlikely to get accidental collissions wis only a few bunches of protons which are not realiy syncroniced for intended collissions.

Wallmott wrote:Since both beams were running, does that mean that they collided at any point?

No. As said before, the bunches weren't synchronised, and also the beams are deflected in the IPs so that they aren't actually crossing paths until official collisions/Physics runs

I agree about the point with the bunches, but at least in the december 2009 run the beams never were deflected in a way that they would not intersect in the detectors, evenso many observers expected like this the message was the did not do that. I have no ifo if they changed this behavior for this run.

I saw an interesting point made on The Register about that. The previous record collision was two 1.18TeV beams colliding at a total of 2.36TeV. By dumping the 3.5TeV beam into the graphite dump blocks, they achieved a new record 3.5TeV collision!

OK, so it's a proton-carbon collision with no detectors present. Still interesting to think about.

PsaltyDS wrote:I saw an interesting point made on The Register about that. The previous record collision was two 1.18TeV beams colliding at a total of 2.36TeV. By dumping the 3.5TeV beam into the graphite dump blocks, they achieved a new record 3.5TeV collision!

OK, so it's a proton-carbon collision with no detectors present. Still interesting to think about.

Well I just read that article and guess who pointed out the collision 'record' ? (It's on the second page)

http://www.theregister.co.uk/2010/03/19 ... int_5_tev/

PsaltyDS wrote:By dumping the 3.5TeV beam into the graphite dump blocks, they achieved a new record 3.5TeV collision!

A 3.5 TeV proton hitting a stationary proton will have only a tiny fraction of the center-of-mass energy that two 3.5 TeV protons colliding would have. So the beam dump wouldn't have any collisions of scientific interest.

Beams Injected, another 3.5TeV Ramp starting NOW!!

Now this is D day. They have reached 3.5 TEV for one hour now. The "1" display reads "3526 GEV" and the status message says: "B1 and B2 circulating / optics measurements at 3.5 TEV".

Very strange. "1" display shows: "I(B1) = 0" and "I(B2)=0" but obviously they have a beam in there, otherwise they would not be tuning the magnets ? Strange ?

Now they are ramping down! There does not appear to be anything left! Did they dump the particles, or try to collide them, or lost them? The status message never mentioned anything! I wish that they would give us more info, or some sound!

The whole cycle took about 4 hours.

Do they have an IRC channel, or TWITTER, or MSN or anything that would allow us to be closer to the action?

(web cam ?)