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Depends on the bunch structure. The PS can deliver up to 72 bunches without gap. Nominally the SPS accumulates four of those trains with a short gap of 8*25ns (not sure about the 8) in between (necessary for the SPS injection magnets), then injects them into the LHC, where a longer gap (28*25 ns) is...

New lumi record, Atlas 1.08 e34, design target reached. Even the average between ATLAS and CMS was slightly (~1%) above 1E34. They changed the SPS injection a bit, instead of one train with 72 bunches they injected two trains with 48 bunches each, that reduced the heat load on the LHC dipole magnet...

I swear i am not crazy, as of yesterday it wasn't included. How are you getting 6.1fb? The overview page shows 5.85fb for Atlas. If you include the current fill it would be ~6.3 fb. Just curious in case you know of a more accurate place for lumi data than the statistics page. I included the (then) ...

Huh? It is in the overview and also in the supertable for me. ~6.1/fb so far, 1.5 times the 2015 dataset. The combined 10/fb also mean that we should surpass the statistics of nearly every 8 TeV result now, as most cross sections increase by a factor of 2 or more. ATLAS shows 450/pb for the current ...

~3 last year, 5 this year, would be 7 to go in a month or less. Not impossible, but not easy either. But independent of the final number, it should be sufficient to see what happens to the diphoton excess. Some LINAC2 issues lead to a lower luminosity for the current fill, let's hope they fix that s...

Note that the July 15 is just the guess of this theorist. The experimental collaborations will have to see how much data they can include while keeping enough time for a proper analysis. We have two relevant data-points: - The Higgs discovery included data taken two weeks before the presentation was...

The difference between the shown values is a few percent. The experiments are happy if the luminosity uncertainty towards the end of the year is a few percent, the online calibration is worse. The difference is probably just a different calibration, while both experiments really get a very similar l...

You don't need any account for the morning meeting slides as far as I know.

Wednesday is reserved for beta*=2.5 km runs, no relevant luminosity from that day probably, but apart from that: sure. Edit: >=24 hour run with 0.51/fb for ATLAS / 0.49/fb for CMS yesterday to today morning. Programmed dump after the luminosity was too low. CERN discusses some of those records 2/fb ...

The technical stop is over, and we directly got a record run! Started 0:20, dump is expected for 22:00 (in 2 hours), so the numbers will go up a bit more. - Luminosity record : ~8.6*10^33, 86% design luminosity, displayed by ATLAS - Integrated luminosity in 24 hours, in a single run, and within a da...

Unplanned dumps in stable beams are usually at random times and don't depend much on the previous time in stable beams. The risk to lose the next fill after an hour is not much larger than the risk of losing the current fill after an hour. Sure, it has to be taken into account because it makes the a...

2/(fb*week) is challenging - possible, but needs more than 50% of the time in stable beams (55% assuming an average of 6000 Hz/µb). Usually 1/3 is more realistic, for ~1.4/(fb*week), about the plan linked above.

Some updated records: - Longest time in stable beams : 35 hours 24 minutes, the run mentioned in the last post. - Luminosity record : 7.9*10^33/(cm^2*s), or 79% design luminosity, by ATLAS yesterday evening and again this morning. CMS shows lower luminosity values, which is probably just a different...

It is still unclear how long repair of the SPS vacuum leak will take. We'll have to live with the gaps in the meantime - they are the time necessary to ramp up/down the kicker magnets for injection, so they cannot be shortened. They are 38 bunches long, so ideally we get 72 bunches per 110*25 = 2750...

The red line is not as problematic as the other lines (it just means horizontal and vertical tune are the same). If it hits one of the other lines, I don't think they can keep the beam.