# Physics Beyond Colliders Kickoff Workshop

Sep 6 – 7, 2016
CERN
Europe/Zurich timezone
There is a live webcast for this event.
REGISTRATION IS NOW CLOSED.

## AFTER@LHC : A fixed-target programme at the LHC for heavy-ion, hadron, spin and astroparticle physics

Sep 7, 2016, 2:40 PM
20m
500/1-001 - Main Auditorium (CERN)

72
Show room on map

### Speaker

Jean-Philippe Lansberg (IPN Orsay, Paris Sud U. / IN2P3-CNRS)

### Description

In this talk, we review a number of recent ideas$^*$ put forward in favour of a fixed-target programme at the LHC - AFTER@LHC- dedicated to heavy-ion, hadron, spin and astroparticle physics. By extracting the beam with a bent crystal or by using an internal gas target, the multi-TeV LHC beams allow one to perform the most energetic fixed-target experiments ever with which one can access the essentially uncharted backward kinematics with detectors similar to LHCb or ALICE.

In particular we argue that this allows one to study $pp$, $pd$ and $pA$ collisions at $\sqrt{s_{NN}}\simeq$115 GeV and Pb$p$ and Pb$A$ collisions at $\sqrt{s_{NN}}\simeq$72 GeV with extremely high precision with modern detection techniques. Such studies, including

• single transverse-spin asymmetries for hard and rare processes,
• suppression of heavy-flavours and quarkonia as well as azimuthal asymmetries down to the target rapidity in heavy-ion collisions,
• cold-nuclear matter effects,
• the physics involved in ultra-peripheral hadron and ion collisions,
• far backward gluon and heavy-quark sensitive processes,
• vector-boson production near threshold ...,

would greatly complement collider experiments, in particular those of the Electron-Ion Collider project or RHIC (with luminosities larger by 1 to 3 orders of magnitude).

Such a mode indeed allows for a broad physics programme, covering the large-$x$ QCD frontier for particle and astroparticle physics, as well as spin and heavy-ion physics with respectively a polarised target and the LHC lead beam.

$^*$: for a complete list of references see
http://after.in2p3.fr/after/index.php/Recent_published_ideas_in_favour_of_AFTER@LHC

### Primary author

Jean-Philippe Lansberg (IPN Orsay, Paris Sud U. / IN2P3-CNRS)