| Paper |
Title |
Page |
| MOPAN073 |
Parametric Study of Heat Deposition from Collision Debris into the Insertion Superconducting Magnets for the LHC Luminosity Upgrade
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323 |
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- C. Hoa, F. Cerutti, J.-P. Koutchouk, G. Sterbini, E. Y. Wildner
CERN, Geneva
- F. Broggi
INFN/LASA, Segrate (MI)
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With a new geometry in a higher luminosity environment, the power deposition in the superconducting magnets becomes a critical aspect to analyze and to integrate in the insertion design. In this paper, we quantify the power deposited in magnets insertion at variable positions from the interaction point (IP). A fine characterization of the debris due to the proton-proton collisions at 7 TeV, shows that the energetic particles in the very forward direction give rise to non intuitive dependences of the impacting energy on the magnet front face and inner surface. The power deposition does not vary significantly with the distance to the interaction point, because of counterbalancing effects of different contributions to power deposition. We have found out that peak power density in the magnet insertion does not vary significantly with or without the Target Absorber Secondaries (TAS) protection.
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| THPAN072 |
A Concept for the LHC Luminosity Upgrade Based on Strong Beta* Reduction Combined with a Minimized Geometrical Luminosity Loss Factor
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3387 |
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- E. Todesco, R. W. Assmann, J.-P. Koutchouk, E. Metral, G. Sterbini, F. Zimmermann, R. de Maria
CERN, Geneva
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A significant increase of the LHC beam current touches physics limits as collective effects, electron-cloud, heat load, collimation and machine protection. We propose an upgrade scheme mainly based on a stronger focusing, with a beta* of 10 cm, requiring a triplet quadrupole aperture of around 130 mm. The performance is further improved if the triplet is based on the Nb3Sn technology. In the present baseline, this beta* reduction provides a negligible luminosity increase: this approach requires a drastic action to minimize the crossing angle, while the beam separation at the long-range encounters has to be increased. This is provided by an early separation scheme made of small dipoles inside the detectors. Optionally, a small angle crab cavity scheme may totally suppress the residual crossing angle. The quadrupole aperture is calculated to allow a larger gap for the collimator, suppressing their impedance limitation. This concept offers high performance while significantly reducing the risks associated to a beam current increase; it opens as well new issues that deserve further studies, such as the dipole integration in the detector, and the correction of the triplet aberrations.
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