Two incoming protons. A burst of outgoing particles. Read the tracks and energy deposits that turn a fleeting collision into a lasting record. Or go deeper: inside the proton, where quarks and gluons begin the story.
PARTICLE COLLISION CHAMBER SCHEMATIC / SLOW MOTION / NOT TO SCALE
EVENT PREVIEW / HADRON JETS
QUARKS → JETS / PAUSE AT A DIFFERENT SCALE
Magnified composition: two up + one down valence quarks, amid gluons and a quark–antiquark sea. Positions, colors, and curled field guides are symbolic; this is not an orbit model.
Play the collision or quark sequence, or choose “Show full event” to jump straight to the completed tracks and detector hits. The stage buttons pause the quark sequence for inspection.
Choose a signature below to explore its research file.
EDUCATIONAL EVENT / NO MEASURED DATA
SELECT A PARTICLE / FOLLOW ITS STORY
A spray of composite particles
A jet groups many hadrons traveling in a similar direction. Solid curves represent charged hadrons; dashed guides represent neutral ones. Energy deposits appear in the hadronic calorimeter. These particular tracks and deposits are illustrative.
Energy deposited in the calorimeter
PARTICLE KEY
DETECTOR SIGNATURES
INSIDE THE PROTON
Choose an entry to see its explanation and matching view. Quarks and gluons appear in magnified stages; the detector records the resulting hadrons.
FILE 01 / MATTER & QUANTUM
The spray has structure
HADRONS / A JET IS MANY PARTICLES
A proton has internal structure. In a high-energy proton collision, interactions between its quarks and gluons can produce outgoing quarks or gluons that develop into jets of hadrons. A jet is a group of particles, not one large particle. This teaching event pairs two illustrative sprays; it does not reconstruct a particular recorded collision.
Why are some lines dashed?
Solid curves mark charged particles. Dashed neutral guides explain where other energy deposits could come from. A neutral particle has no ordinary charged track in the inner tracker. The detector combines many pieces of information to reconstruct a jet.
An electron and its antiparticle, the positron, respond oppositely to the detector’s magnetic field. Their paths lead to energy deposits in the electromagnetic calorimeter. Here the branching light marks an illustrative shower of secondary particles; it is not a photograph of visible sparks.
How does this relate to an electron in an atom?
The particle is familiar, but the setting has changed. An atomic probability cloud describes a bound quantum state. The displayed collider curve reconstructs a high-energy charged particle’s passage through a detector. Our atom view and electron Field Note offer two different ways to pursue that distinction.
A photon is electrically neutral. In this simplified view it travels along a dashed guide and starts a shower in the electromagnetic calorimeter. An electron can leave both an inner charged track and an electromagnetic energy deposit. Comparing those signatures helps explain why several detector layers are necessary.
Does a pair of photons identify the particle that made it?
A pair by itself does not establish a discovery. Researchers compare many events, reconstructed quantities, expected backgrounds, and uncertainties. This preset deliberately names the outgoing signature without labeling its origin as a Higgs boson or another parent particle.
Muons can pass through the calorimeters and leave measurements in the detector’s outer muon system. Our markers fade after leaving the illustrated volume. The remaining lines stand for reconstructed records, not particles frozen in place. The event ends with information that a physicist can inspect.
Where do short-lived particles fit?
Many unstable particles decay before they can cross a detector. Their products may be what researchers reconstruct. For example, top-quark decays can yield jets, electrons or muons, and neutrinos. This muon preset is a simpler signature illustration, not a complete top-quark event.
Begin inside a proton: its valence content is two up quarks and one down quark. That shorthand describes the excess over antiquarks, not everything inside. Gluons and a sea of quark–antiquark pairs are also part of the proton. The enlarged u, u, and d markers separate the labels for clarity; they do not show fixed positions or orbits. The up quark carries +⅔ of the proton’s electric charge; the down quark carries −⅓.
Why do the quark labels disappear before the detector?
In the second view, a selected up quark from one proton and a down quark from the other scatter. Both quarks radiate gluons; gluons branch further. The rest of each proton is omitted. This is one schematic parton shower, not a universal collision outcome. Through hadronization, quarks and gluons form composite hadrons. The third view changes scale to show illustrative hadron jets in the detector. It does not simulate that complex conversion. Isolated quarks do not draw tracks across the detector: researchers use the hadrons and their energy deposits to study the underlying partons.
Charged particles leave measurements in tracking layers. A magnetic field bends their paths; curvature helps researchers determine momentum and charge. The colored lines here make that reconstruction legible. They are not trails of visible light in the laboratory.
02 / FOLLOW THE ENERGY
A shower ends in a record.
Calorimeters register energy deposited by particles and their showers. The moving dot disappears as its energy transfers to material; a bright block remains in our display to represent a measurement. Muons continue outward to another detector system.
03 / KNOW WHAT IS OMITTED
One signature is not a full collision.
The first four presets isolate recognizable detector patterns. “Quarks → Jets” adds a separate, magnified explanation of what precedes a hadron jet. Real proton collisions include beam remnants, additional activity, and sometimes multiple overlapping interactions. Neutrinos may escape detection. This model does not solve or reconstruct the complete event.
This original interactive model is a teaching illustration inspired by cylindrical collider detectors. Its geometry, field, timing, particle selection, tracks, showers, light effects, and energy blocks are schematic. It is not an engineering model of ATLAS or CMS, a recorded event, or an event-generator calculation. The two incoming proton markers stand for a selected collision within opposing beams. Only selected outgoing signatures are drawn; the display is not a complete energy, momentum, or charge accounting. The flash marks the interaction for the viewer, and all motions are enormously slowed. Charged curves are simplified; dashed neutral paths are explanatory guides. Recorded traces remain after moving markers fade.
“Quarks → Jets” deliberately changes magnification between the proton, a parton shower, and the detector. The colored u, d, and g symbols identify particle types; these display colors are not QCD color-charge assignments. Proton contours, sea speckles, field curls, and shower branches are explanatory artwork, not fixed constituent positions or measured paths. The selected u + d scattering draws one quark from each incoming proton; it omits the rest of both protons and other possible interactions. Hadronization is explained between views, not computed. Only hadrons appear in the final detector view.
Detector tracks are selected signatures of a larger event.
The illustrated photons, leptons, quarks, and jets help explain different roles in a collision. This is not a complete energy, momentum, or charge accounting. Replaying an event teaches the key but does not create independent experimental evidence.
Ask yourself Which assumptions drive this result, and where would the model stop being useful?
THE SIGNAL CONTINUES
Some discoveries stay with you.
Get the illustrated investigations delivered to your inbox. Then follow the questions that refuse to leave.
