Инженеры ЦЕРН впервые извлекли оборудование из Большого адронного коллайдера для масштабной модернизации

The Large Hadron Collider may be silent, but its tunnel has never been more crowded with purposeful motion. On September 2, CERN engineers completed the first-ever LHC hardware extraction — a categorical milestone that marks the first time in the collider's 18-year history that large-scale hardware has physically left the accelerator ring, not because something failed, but because the machine itself is being taken apart and rebuilt as something more powerful. The operation required three years of dedicated preparation, a custom-built towing vehicle designed from scratch, and eight hours of painstaking underground transit for each component — and it is only the beginning of what CERN describes as the most extensive intervention on its accelerator complex since the LHC was originally constructed. What Engineers Actually Removed — and Why It Matters The extracted components are TAN absorbers: 5-metre-long (16.4 ft) blocks of iron, copper, and marble, each weighing 30 tonnes (66,139 lbs, or approximately 33 US tons). Their function inside the collider is unspectacular to describe and critical in practice. When proton beams collide at the LHC's main interaction points — near the ATLAS and CMS experiments — the resulting spray of particles includes a population of neutrally charged particles: neutrons, photons, and neutral pions. Unlike their charged counterparts, these neutral particles evade magnetic steering entirely. They travel straight ahead along the beam axis at nearly the speed of light and would, without intervention, plow into the LHC's superconducting dipole magnets approximately 100 to 200 metres (328 to 656 ft) downstream — potentially quenching them, knocking them out of their superconducting state, and disrupting operations across a section of the 27-kilometre (16.8-mile) ring. The TAN absorbers intercept this neutral particle spray before it reaches the magnets. Their iron core initiates hadronic cascades that absorb neutrons and hadronic particles; their copper section stops electromagnetic particles — photons and electrons — whose interaction length in copper is short enough to be caught within the component's depth; and a fused silica and marble inner section houses the BRAN luminosity monitor, a detector that exploits the particle shower to measure the collider's luminosity in real time. The TAN absorbers were first placed in the tunnel in 2006, when the LHC was, by comparison, nearly empty. Twenty years of operation have made them among the most radioactive components in the collider — a fact that shapes every aspect of the extraction logistics, according to CERN's September 2 press release. Not Maintenance: Why This Shutdown Is Different Prior LHC long shutdowns — LS1 (2013–2015) and LS2 (2019–2022) — involved substantial engineering work: repairing faulty electrical splices, consolidating the machine for higher intensity operation, upgrading the injector chain. But those shutdowns were fundamentally exercises in repair and enhancement; components were upgraded or replaced in place. LS3 is a fundamentally different shutdown. Over the course of LS3, approximately 1.2 kilometres (0.75 miles) of the LHC will be physically dismantled and replaced with new systems — particularly around Point 1 (ATLAS) and Point 5 (CMS), where the entire Long Straight Sections will be de-installed and rebuilt with HL-LHC hardware. The TAN absorber extraction is the first act of that dismantling. Hardware is not being upgraded; it is being removed to make room for its successor. The new version — designated the TAXN (Target Absorber for Neutrals, HL-LHC) — will be reinstalled in 2029, engineered to handle the higher radiation load that comes with the HL-LHC's dramatically increased luminosity: up to 200 proton-proton pile-up interactions per bunch crossing, compared with roughly 60 during Run 3, according to the High-Luminosity LHC upgrade program. Three Kilometres Through a Crowded Tunnel Getting the TAN absorbers out required solving an engineering puzzle that was not obvious until it was stared at for three years. The LHC tunnel, at 3.8 metres (12.5 ft) in diameter, is lined with the dense accumulation of two decades' worth of installed equipment — cables, conduits, beam instrumentation, cryogenic lines, and the 1,232 superconducting dipole magnets that bend the beam around the ring. The TAN absorbers, at 5 metres (16.4 ft) long and 30 tonnes (66,139 lbs) each, are among the heaviest and most unwieldy components in the entire machine. When they were installed in 2006, the tunnel was nearly empty; threading them back out through what it has since become was, as CERN project director Maria Perez Ornedo put it, a question of transporting them without damaging existing equipment. The engineering response was to build the tools that did not yet exist. Over three years, CERN's handling teams designed and manufactured a custom tow rig and jacking system — all purpose-built for this single operation. Standard underground handling equipment cannot navigate the tunnel's constraints; the custom vehicle was designed to maneuver each 30-tonne (66,139-lb) block through gaps that, at the tightest points, allowed only a few centimetres of clearance on each side. Each absorber was then hauled approximately 3 kilometres (1.9 miles) through the LHC tunnel — from the vicinity of the ATLAS experiment, located at Point 1, to the underground cavern housing the ALICE detector at Point 2, where a 30-tonne-rated bridge crane was available. The crane then lifted each absorber 100 metres (328 ft) vertically to the surface. The full operation — from the start of the underground transit to the component's arrival at the surface — took eight hours per absorber. The two units extracted on September 2 will be completely dismantled, with their central sections — the most radiation-damaged and functionally critical portions — replaced entirely. Two additional TAN absorbers at different points of the ring are scheduled for extraction soon, completing the first phase of LHC component removal. What Replaces the Hardware Being Removed The components that will eventually fill the space left by the TAN extractions are qualitatively more advanced than what they replace. The HL-LHC upgrade centers on new inner triplet quadrupole magnets wound from niobium-tin (Nb3Sn) superconductor — a material capable of sustaining magnetic fields up to roughly 11 to 12 Tesla, compared with the 8.3 Tesla limit of the niobium-titanium (NbTi) magnets currently in use throughout most of the ring. These stronger fields can squeeze the proton beams into a much tighter focus at the collision points — producing more collisions per unit time, and therefore more data per operational year. The readiness of this hardware was confirmed six weeks before the TAN extraction. On July 8, the IT String — CERN's above-ground, full-scale test stand for the HL-LHC inner triplet system — successfully reached 16,230 amperes nominal current for the first time. The 95-metre (312-ft) test installation validated not just the magnets but the complete integrated system — cryogenics, powering, protection, and alignment — under conditions as close as possible to those of the underground tunnel. A second IT String operational campaign, focused on validating commissioning procedures and demonstrating reproducibility, is underway in September. CERN Director for Accelerators and Technology Oliver Brüning confirmed the new magnets exceed LHC capabilities. The Nb3Sn technology was known to CERN's accelerator physicists for decades — the material was identified as a superconductor in 1954 — but its brittleness made it impractical until the engineering required to manufacture and handle it was developed through a decade-long joint project involving CERN, Brookhaven National Laboratory, Fermilab, Lawrence Berkeley National Laboratory, and Florida State University. Deploying Nb3Sn magnets in an operational particle accelerator will be a world first when the HL-LHC comes online. How Many More Operations Like This Are Coming The September 2 extraction is one of the first in a years-long sequence of "exceptional transport operations," in CERN's framing, that will define the physical character of LS3. CERN has indicated that its handling teams face more complex logistics over the coming months and years — moving, installing, or removing the exceptionally large items of equipment that the full HiLumi LHC upgrade demands. The wider LS3 context makes the scale concrete. On August 31, all of CERN's other accelerators — the Super Proton Synchrotron, Proton Synchrotron Booster, and associated facilities that had continued operating through July and August 2026 — entered LS3 after extracting beams. The entire CERN accelerator complex is now simultaneously in construction mode. The injector complex is scheduled to progressively restart from 2028 onwards; the HiLumi LHC itself will be the last to wake up, with its Run 4 start targeted for mid-2030. The $1.5 billion program involves thousands of specialists from CERN and partner institutes worldwide, replacing 1.2 kilometres of the ring with new hardware and adding entirely new underground infrastructure — technical galleries, vertical core connections, and new surface buildings — that will house the HL-LHC's novel powering and cryogenic systems. That program is now physically underway. Read more: Two Z Bosons and Photon Produced Together: LHC Finds First Evidence of ZZgamma in Eight Events What the HiLumi Machine Is Being Built to Do The TAN extraction's significance as a construction milestone is inseparable from the physics it is enabling. The HL-LHC is designed to reach a peak luminosity — the rate of proton-proton collisions per unit area per second — of five to 7.5 times the LHC's nominal design value, producing 140 to 200 pile-up interactions per bunch crossing compared with roughly 60 during Run 3. Over its operational lifetime, the HL-LHC is projected to deliver approximately 100 times more total collision data than the LHC accumulated across its entire operational history — an integrated luminosity of roughly 3,000 to 4,000 inverse femtobarns — according to the HL-LHC program's stated targets — compared with the hundreds of inverse femtobarns produced by Runs 1 through 3 combined. That data volume translates to specific physics capabilities the current LHC cannot reach. The most consequential is direct measurement of the Higgs self-coupling — the constant that determines the shape of the Higgs field potential and, with it, whether the electroweak vacuum in which all of observable reality exists is genuinely stable or merely the lowest available energy state in a landscape that includes a deeper one. Accessing that measurement requires observing two Higgs bosons produced simultaneously in a single proton-proton collision, a process so rare that the full LHC run from 2008 to 2026 was not sufficient to produce a statistically meaningful result. The LHC that returns to operation in 2030 will be a fundamentally different machine than the one that circulated its first proton beams in September 2008. The extraction of two iron-and-marble blocks from a crowded underground tunnel is, improbably, the physical act that opens that next chapter. Frequently Asked Questions What is a TAN absorber, and why does removing it require custom equipment? TAN stands for Target Absorber for Neutrals. It is a 5-metre (16.4-ft) block of iron, copper, and marble positioned approximately 140 metres (459 ft) downstream from the LHC's main collision points. Its function is to absorb neutral particles produced in proton-proton collisions — particles that cannot be steered by magnetic fields and would otherwise damage the superconducting magnets further down the tunnel. Removing it requires custom equipment because the LHC tunnel is 3.8 metres (12.5 ft) in diameter and has accumulated two decades of densely installed equipment since the TAN was first placed there in 2006. Standard industrial cranes and forklifts cannot fit or maneuver; CERN had to design and build a purpose-made towing vehicle, rolling platform, and jacking system from scratch over three years. At the tightest tunnel sections, the convoy moved with only a few centimetres of clearance on each side. Does removing TAN absorbers mean the LHC is shutting down permanently? No. The removal is part of Long Shutdown 3, a planned four-year upgrade program that began June 29, 2026. The LHC's existing TAN absorbers are being removed to make room for their upgraded successors — the TAXN — which will be reinstalled in 2029 and will handle the higher radiation loads expected when the HL-LHC operates at up to 200 pile-up collisions per bunch crossing. The rebuilt machine, the High-Luminosity LHC, is scheduled to begin its first physics run (Run 4) in mid-2030. Why is the HL-LHC described as a "different machine" if it uses the same 27-kilometre tunnel? The 27-kilometre ring and the LHC's 13.6 trillion electronvolt (TeV) collision energy are not changing. What is being replaced is approximately 1.2 kilometres (0.75 miles) of the tunnel's internal hardware — the focusing magnets, absorbers, crab cavities, collimators, and superconducting power links near the main ATLAS and CMS collision points. The new inner triplet quadrupole magnets use a different superconducting material (niobium-tin rather than niobium-titanium), enabling stronger magnetic fields that squeeze proton beams into tighter collisions and increase the luminosity — the collision rate — by up to a factor of ten. In physics terms, more luminosity means more rare-process observations, which is the entire scientific purpose of the upgrade. What will the HL-LHC discover that the LHC could not? The HL-LHC's primary new physics target is the Higgs self-coupling — a measurement that requires observing two Higgs bosons produced simultaneously in a single collision, a process so rare that the LHC's entire 18-year dataset was insufficient to reach conclusive sensitivity. The HL-LHC is also designed to perform precision measurements of the W boson mass, rare B-meson decays, top-quark properties, and anomalous Higgs couplings to other particles — measurements that could reveal deviations from Standard Model predictions pointing toward new physics. What it will not do is exceed the LHC's collision energy of 13.6 TeV; that frontier belongs to any potential successor machine, such as the proposed Future Circular Collider, whose construction decision is expected around 2028. ⓒ 2026 TECHTIMES.com All rights reserved. Do not reproduce without permission.