|
|
This Web page provides advanced "preprint" versions of our papers, slides, posters, other papers, outreach pages and videos and links to other material giving fuller information about our recent work. Please follow the links in the titles of the following excerpts from the conference programme.
This page is still evolving, more links will be added.
Please note that the definitive versions of the papers will be available from
the conference proceedings Web site.
MOODB201 | Proton-nucleus Collisions in the LHC - Preprint - Slides | |
---|---|---|
Contributed Oral | ||
Location | Grand Ballroom 2 | |
Time | Monday, 13-MAY-13 15:00 - 15:20 | |
Speaker | John M. Jowett - European Organization for Nuclear Research Beams Department (BE) | |
Abstract | Following the high integrated luminosity accumulated in the first two Pb-Pb collision runs in 2010 and 2011, the LHC heavy-ion physics community requested a first run with p-Pb collisions. This almost unprecedented mode of collider operation was not foreseen in the baseline design of the LHC whose two-in-one magnet design imposed equal rigidity and, hence, unequal revolution frequencies, during injection and ramp. Nevertheless, after a successful pilot physics fill in 2012, the LHC provided 31 nb^-1 of p-Pb luminosity per experiment, at an energy of 5.02 TeV per colliding nucleon pair, with several variations of the operating conditions, in early 2013. Together with a companion p-p run at 2.76 TeV, this was the last physics before the present long shutdown. We summarise the beam physics, operational adaptations and strategy that resulted in extremely rapid commissioning. Finally, we give an account of the progress of the run and provide an analysis of the performance. |
Latest tweets on the p-Pb run (click
on the hashtag to relive the history from early January 2013) Tweets about "#pArunatLHC" |
Selected news items and outreach materials on the first proton-nucleus run of the LHC.
Further technical papers and talks on the first proton-nucleus run of the LHC.
Links to some of the physics results.
TUPFI041 | Operating the LHC Off-momentum for p-Pb Collisions - Preprint - Poster |
---|---|
Location | Fire Poster Area |
Time | Tuesday, 14-MAY-13 00:00 - 18:00 |
Presenter | Reine Versteegen - European Organization for Nuclear Research Beams Department (BE) |
Abstract | The first high-luminosity p-Pb run at the LHC took place in January-February 2013 at an energy of 4 Z TeV per beam. The RF frequency difference of proton and Pb is about 60 Hz for equal magnetic rigidities, which means that beams move slightly to off-momentum, non-central, orbits during physics when frequencies are locked together. The resulting optical perturbations ("beta-beating") restrict the available aperture and required a special correction. This was also the first operation of the LHC with low beta in all four experiments and required a specific collimation set up. Predictions from offline calculations of beta-beating correction are compared with measurements during the optics commissioning and collimator set up. |
TUPFI025 | Bunch-by-Bunch Analysis of the LHC Heavy-Ion Luminosity - Preprint - Poster |
---|---|
Location | Fire Poster Area |
Time | Tuesday, 14-MAY-13 00:00 - 18:00 |
Presenter | John M. Jowett - but main author is Michaela Schaumann |
Abstract | After the first run in 2010, the LHC continued its heavy-ion operation with collisions of lead nuclei in late 2011. The beam dynamics of those high intensity lead beams are strongly influenced by intra-beam scattering (IBS), especially on the injection plateau. Each batch injected from the SPS spends a different time at injection, introducing significant changes from batch to batch. Within the batches there is an even larger spread imprinted by the SPS injection plateau. This results in a spread of the luminosity produced in each bunch crossing. The particle losses during collisions are dominated by nuclear electromagnetic processes, leading to a non-exponential intensity decay during the fill and short luminosity lifetime at 3.5 Z TeV. The luminosity, emittance, intensity and bunch length evolution of the 2011 run was analysed bunch-by-bunch and compared with simulations. Based on this analysis, estimates of the potential luminosity performance at 6.5 Z TeV, after the present shutdown, are given. |
TUPFI024 | Influence of the ATS Optics on Intra-beam Scattering for HL-LHC - Preprint - Poster | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Location | Fire Poster Area | ||||||||||||
Time | Tuesday, 14-MAY-13 00:00 - 18:00 | ||||||||||||
Presenter | John M. Jowett - but main author is Michaela Schaumann | ||||||||||||
Abstract | In the future High Luminosity (HL-)LHC the influence of intra-beam scattering (IBS) will be stronger than in the present LHC, because of higher bunch intensity, small emittance and new optics. The new ATS-optics scheme modifies the lattice in the arcs around the main interaction points (IP) to provide β* values as small as 0.15m in the IP, however those modifications affect the IBS growth rates. In this paper proton IBS emittance growth rates are calculated with MADX and the Collider Time Evolution (CTE) program for two ATS-optics versions, different settings of the crossing angles and required corrections and various beam conditions at injection (450 GeV) and collision (7 TeV) energy. CTE simulations of the expected luminosity, intensity, emittance and bunch length evolution during fills are also presented | ||||||||||||
|
WEPEA060 |
Plans for the Upgrade of CERN's Heavy Ion Complex - Preprint - Poster | ||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Poster | |||||||||||||||||||||
Location | Earth Poster Area | ||||||||||||||||||||
Time | Wednesday, 15-MAY-13 00:00 - 18:00 | ||||||||||||||||||||
Presenter | Django Manglunki - European Organization for Nuclear Research Beams Department (BE) | ||||||||||||||||||||
Abstract | To reach a luminosity higher than 6×10^27 Hz/cm2 for Pb-Pb collisions, as expected by the ALICE experiment after its upgrade during the 2nd Long LHC Shutdown (LS2), several upgrades will have to be performed in the CERN accelerator complex, from the source to the LHC itself. This paper first details the present limitations and then describes the strategy for the different machines in the ion injector chain. Both filling schemes and possible hardware upgrades are discussed. | ||||||||||||||||||||
|
|