LHCf experiment
| Plan of the LHC experiments and the preaccelerators. | |
| LHC experiments | |
|---|---|
| ATLAS | A Toroidal LHC Apparatus |
| CMS | Compact Muon Solenoid |
| LHCb | LHC-beauty |
| ALICE | A Large Ion Collider Experiment |
| TOTEM | Total Cross Section, Elastic Scattering and Diffraction Dissociation |
| LHCf | LHC-forward |
| MoEDAL | Monopole and Exotics Detector At the LHC |
| FASER | ForwArd Search ExpeRiment |
| SND | Scattering and Neutrino Detector |
| LHC preaccelerators | |
| p and Pb | Linear accelerators for protons (Linac 4) and lead (Linac 3) |
| (not marked) | Proton Synchrotron Booster |
| PS | Proton Synchrotron |
| SPS | Super Proton Synchrotron |
The LHCf (Large Hadron Collider forward) is a special-purpose Large Hadron Collider experiment for astroparticle (cosmic ray) physics, and one of nine detectors in the LHC accelerator at CERN. LHCf is designed to study the particles generated in the forward region of collisions, those almost directly in line with the colliding proton beams.[1]
Purpose
[edit ]The LHCf is intended to measure the energy and numbers of neutral pions (π0
) produced by the collider. This will hopefully help explain the origin of ultra-high-energy cosmic rays (UHECRs).[2] [3] Detecting UHECRs is performed through observations of secondary particle showers produced when a UHECR interacts with the atmosphere. The LHCf experiment is designed to measure the very-forward region, where most of the energy flow of secondary particles is contained.[3]
The results produced by the LHCf experiment complement other high-energy cosmic ray measurements from the Pierre Auger Observatory in Argentina, and the Telescope Array Project in Utah.[4] [5]
Experimental setup
[edit ]The LHCf setup consists of two independent detectors on either side of the LHC, both 140 m from the ATLAS interaction point.[6] [7] The detectors are referred to as Arm 1 and Arm 2 and are installed inside target neutral absorbers (TAN), which protect cryo-magnets from neutral particle debris from the interaction region.[8] [9] [10]
The two detectors have a common structure of two independent calorimeter towers, for photon and neutron measurements. The towers are made from tungsten absorber layers and scintillator layers, with a difference in the size of transverse sections for the two arms.[11] The calorimeter towers are used to measure incoming particle energy and to identify families of particles. Each detector has a tracking system: the Arm 1 system consists of four double-layers os scintillating fibres; Arm 2 consists of microstrip silicon layers.[12] The energy resolution for the detectors is over 3% for photons above 100 GeV and around 40% for neutrons.[11] [3] The position resolution for Arm 1 and Arm 2 is 200 μm and 40 μm for photons respectively, and is around 1 mm for neutrons for both the detectors.[11] [13] [3]
Results
[edit ]The first phase of data using the LHCf detectors was recorded in 2009–2013, as part of the LHC's Run 1.[14] The LHCf results at 7 TeV centre-of-mass energy showed good agreement with theoretical models for forward photon and neutral pion production. However, the results did not agree for the forward neutron production.[15] [16]
LHCf was able to measure how the number of forward photons and neutrons varies with energy at new high energies. The results of the experiment agree with some theoretical models but disagree with other.[17] [18] [19]
The current focus of the LHCf is to look out for neutral kaons and neutral eta mesons, particles that include a strange quark. The theoretical models describing this interaction predict secondary muons, but the predicted numbers disagree with experimental data. The LHCf experiment hopes to resolve the "muon puzzle".[20] [21]
References
[edit ]- ^ "LHCf". CERN. 2023年07月21日. Retrieved 2023年08月07日.
- ^ LHCf Collaboration; Adriani, O.; Berti, E.; Bonechi, L.; Bongi, M.; D'Alessandro, R.; Del Prete, M.; Haguenauer, M.; Itow, Y.; Iwata, T.; Kasahara, K.; Kawade, K.; Makino, Y.; Masuda, K.; Matsubayashi, E. (2016年08月22日). "Measurements of longitudinal and transverse momentum distributions for neutral pions in the forward-rapidity region with the LHCf detector". Physical Review D. 94 (3) 032007. arXiv:1507.08764 . Bibcode:2016PhRvD..94c2007A. doi:10.1103/PhysRevD.94.032007. S2CID 111375019.
- ^ a b c d Tiberio, Alessio; Adriani, O.; Berti, E.; Betti, P.; Bonechi, L.; Bongi, M.; D'Alessandro, R.; Haguenauer, M.; Itow, Y.; Kasahara, K.; Kondo, M.; Matsubara, Y.; Menjo, H.; Muraki, Y.; Ohashi, K. (2023年07月25日). "The LHCF experiment at the Large Hadron Collider: Status and prospects". Proceedings of 38th International Cosmic Ray Conference. p. 444. doi:10.22323/1.444.0444 .
- ^ Noda, K; Adriani, O; Bonechi, L; Bongi, M; et al. (Sep 2011). "The LHCf experiment". VI European Summer School on Experimental Nuclear Astrophysics.
- ^ "What is LHCf?". US/LHC. 2015年03月03日. Archived from the original on 2015年03月03日. Retrieved 2023年08月08日.
- ^ "LHCf: a tiny new experiment joins the LHC". CERN Courier. 2006年11月01日. Retrieved 2023年08月07日.
- ^ Adriani, Oscar (9 Sep 2005). "The LHCf experiment at LHC" (PDF). Retrieved 7 Aug 2023.
- ^ Collaboration, The LHCf; Adriani, O; Bonechi, L; Bongi, M; Castellini, G; D'Alessandro, R; Faus, D A; Fukui, K; Grandi, M; Haguenauer, M; Itow, Y; Kasahara, K; Macina, D; Mase, T; Masuda, K (2008年08月14日). "The LHCf detector at the CERN Large Hadron Collider". Journal of Instrumentation. 3 (8) S08006. Bibcode:2008JInst...3S8006L. doi:10.1088/1748-0221/3/08/S08006 . hdl:10550/42770 . ISSN 1748-0221. S2CID 250679205.
- ^ Piparo, Giuseppe (2023年07月25日). "Measurement of the very forward π0 and η meson productions in p-p collisions at √s=13 TeV with the LHCF detector". Proceedings of 38th International Cosmic Ray Conference. p. 447. doi:10.22323/1.444.0447 .
- ^ Adriani, O.; Bonechi, L.; Bongi, M.; Castellini, G.; D'alessandro, R.; Haguenauer, M.; Iso, T.; Itow, Y.; Kasahara, K.; Kawade, K.; Masuda, K.; Menjo, H.; Mitsuka, G.; Muraki, Y.; Noda, K. (2013年10月10日). "LHCf DETECTOR PERFORMANCE DURING THE 2009–2010 LHC RUN". International Journal of Modern Physics A. 28 (25): 1330036. Bibcode:2013IJMPA..2830036A. doi:10.1142/S0217751X13300366. ISSN 0217-751X.
- ^ a b c Makino, Y.; Tiberio, A.; Adriani, O.; Berti, E.; Bonechi, L.; Bongi, M.; Caccia, Z.; D'Alessandro, R.; Prete, M. Del; Detti, S.; Haguenauer, M.; Itow, Y.; Iwata, T.; Kasahara, K.; Masuda, K. (2017年03月21日). "Performance study for the photon measurements of the upgraded LHCf calorimeters with Gd 2 SiO 5 (GSO) scintillators" . Journal of Instrumentation. 12 (3) P03023. Bibcode:2017JInst..12P3023M. doi:10.1088/1748-0221/12/03/P03023. ISSN 1748-0221. S2CID 125806123.
- ^ Bonechi, Lorenzo (2008年03月01日). "LHCf: a LHC Detector for Astroparticle Physics" . Nuclear Physics B - Proceedings Supplements. Proceedings of the Hadron Collider Physics Symposium 2007. 177–178: 263–264. Bibcode:2008NuPhS.177..263B. doi:10.1016/j.nuclphysbps.2007年11月12日2. hdl:10261/9064 . ISSN 0920-5632.
- ^ Adriani, O; Bonechi, L; Bongi, M; Castellini, G; Ciaranfi, R; D'Alessandro, R; Grandi, M; Papini, P; Ricciarini, S; Tricomi, A; Viciani, A (2010年01月26日). "The construction and testing of the silicon position sensitive modules for the LHCf experiment at CERN". Journal of Instrumentation. 5 (1) P01012. Bibcode:2010JInst...5.1012A. doi:10.1088/1748-0221/5/01/P01012. ISSN 1748-0221. S2CID 250686091.
- ^ "LHC report: Run 1 - the final flurry". CERN. 2023年07月21日. Retrieved 2023年08月08日.
- ^ "Smaller LHC collaborations to analyse collisions at 13 TeV". CERN. 2023年07月21日. Retrieved 2023年08月08日.
- ^ Adriani, O.; Berti, E.; Bonechi, L.; Bongi, M.; Castellini, G.; D'Alessandro, R.; Del Prete, M.; Haguenauer, M.; Itow, Y.; Kasahara, K.; Kawade, K.; Makino, Y.; Masuda, K.; Matsubayashi, E.; Menjo, H. (Nov 2015). "Measurement of very forward neutron energy spectra for 7 TeV proton--proton collisions at the Large Hadron Collider". Physics Letters B. 750: 360–366. arXiv:1503.03505 . Bibcode:2015PhLB..750..360A. doi:10.1016/j.physletb.2015年09月04日1. S2CID 118480688.
- ^ "LHCf gears up to probe birth of cosmic-ray showers". CERN. 2023年07月21日. Retrieved 2023年08月08日.
- ^ Adriani, O.; Berti, E.; Bonechi, L.; Bongi, M.; D'Alessandro, R.; Haguenauer, M.; Itow, Y.; Iwata, T.; Kasahara, K.; Makino, Y.; Masuda, K.; Matsubayashi, E.; Menjo, H.; Muraki, Y.; Papini, P. (2018年05月10日). "Measurement of forward photon production cross-section in proton–proton collisions at √s = 13TeV with the LHCf detector". Physics Letters B. 780: 233–239. arXiv:1703.07678 . doi:10.1016/j.physletb.2017年12月05日0 . ISSN 0370-2693. S2CID 53972544.
- ^ Adriani, O.; Berti, E.; Bonechi, L.; Bongi, M.; D'Alessandro, R.; Detti, S.; Haguenauer, M.; Itow, Y.; Kasahara, K.; Makino, Y.; Masuda, K.; Menjo, H.; Muraki, Y.; Ohashi, K.; Papini, P. (2018年11月12日). "Measurement of inclusive forward neutron production cross section in proton-proton collisions at √s = 13 TeV with the LHCf Arm2 detector". Journal of High Energy Physics. 2018 (11): 73. arXiv:1808.09877 . doi:10.1007/JHEP11(2018)073 . ISSN 1029-8479. S2CID 256045598.
- ^ "LHCf continues to investigate cosmic rays". CERN. 2023年07月21日. Retrieved 2023年08月08日.
- ^ Albrecht, Johannes; Cazon, Lorenzo; Dembinski, Hans; Fedynitch, Anatoli; Kampert, Karl-Heinz; Pierog, Tanguy; Rhode, Wolfgang; Soldin, Dennis; Spaan, Bernhard; Ulrich, Ralf; Unger, Michael (2022年03月09日). "The Muon Puzzle in cosmic-ray induced air showers and its connection to the Large Hadron Collider". Astrophysics and Space Science. 367 (3): 27. arXiv:2105.06148 . Bibcode:2022Ap&SS.367...27A. doi:10.1007/s10509-022-04054-5. ISSN 1572-946X. S2CID 234482981.
External links
[edit ]- Media related to LHCf experiment at Wikimedia Commons
- LHCf experiment record on INSPIRE-HEP
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