Like many areas of science, HEP is frequently broken into several subsets that depend heavily on one-another. It’s typically first split into experimental and theoretical studies:

Experimental HEP: Experimentalists deal with the construction and operation of particle colliders, detectors, event triggers, event storage, data analysis, and so-on. Oftentimes experiments require huge teams of experimentalists (called collaborations) in order to run successfully. There are three popularly-recognized classes of experiment:

Colliders: Collider experiments work by slamming two known particles into each other at high energy, usually with the hopes of creating new particles in the process. This is what happens at the LHC.

Direct Detection: Direct detection experiments bring together large amounts of matter and wait to see if anything out of the ordinary occurs. For example, some direct detection experiments use giant vats of liquid xenon to look for evidence of dark matter.

Indirect Detection: Indirect detection experiments look for the consequences of new particles interacting with each other. For example, some models predict that dark matter should annihilate with itself and produce certain kinds of cosmic rays, so some indirect detection experiments look for those cosmic rays.

Theoretical HEP: Theoreticians utilize mathematical modeling techniques and computational simulations to interpret existing experimental data and predict future results. This often involves hypothesizing new fundamental particles and forces. Theoretical groups are typically much smaller than experimental groups. Theory can be further subdivided:

Phenomenological HEP: Phenomenologists walk the line between theory and experiment by using model-building techniques to describe generic features of data. By determining quantifiable predictions of new physics models, they provide tools as to discover (or eliminate) new physics. Phenomenologists frequently utilize effective field theory techniques.

Lattice HEP: Lattice theory is a rapidly growing subfield of HEP theory that deals with lattice QFT, a formulation of QFT on a discretized spacetime. Lattice theoreticians use lattice QCD in combination with modern computation power to solve problems in quantum chromodynamics (QCD).

Pure HEP Theory: Pure HEP theorists work on advanced mathematical QFT frameworks that typically generate predictions beyond the discovery reach of modern particle physics experiments. Popular pure theory topics include string theory and quantum gravity.

There are several journals dedicated to HEP, wherein high energy physicists publish articles, including:

APS Physics Review D (PRD or Phys. Rev. D)

Journal of High Energy Physics (JHEP)

Physics Letters B (Phys. Lett. B)

These journals require subscriptions to access. Thankfully, there are online resources that provide many HEP publications for free! The remainder of this post lists some of these resources.

Particle Data Group: (abbreviated PDG) An international group tasked with summarizing the latest and greatest particle physics results. They provide tables of modern particle property measurements, as well as reviews/summaries of important particle physics topics. Their reviews are EXTREMELY useful. Almost anything you’d want to know about HEP and the techniques used therein are contained in a 1600+ page book that the PDG provides online for free.

Particle Data Group - Home Page

Particle Data Group - Reviews, Tables, and Plots

Particle Data Group - PDG Computer Downloads

ArXiv: (pronounced like “archive”) An online archive of publications from several academic areas, 100% free to the public. Physicists post conference proceedings, note collections, and papers intended for journal publication. The arXiv updates often with cutting edge research.

arXiv - Home Page

arXiv [hep-ex] :: High Energy Physics - Experiment

arXiv [hep-lat] :: High Energy Physics - Lattice

arXiv [hep-ph] :: High Energy Physics - Phenomenology

arXiv [hep-th] :: High Energy Physics - Theory

INSPIRE: Another online archive of publications. INSPIRE provides information on many HEP publications, including where to find many publications that are not hosted on the arXiv.

INSPIRE - Home Page

CERN Document Server: A directory of pretty much everything CERN makes public, including results from the CMS and ATLAS experiments.

CERN Document Server - Home Page

HEPData: Did you find an awesome plot in a publication and want the exact values used by the authors? It’s worth checking HEPData, an open-access repository of data generated by the HEP community.

HEPData - Home Page

Summer Schools: There are many summer schools that provide professional training to physics graduate students and postdocs. These schools often publish compilations of notes from their events which are more pedagogical than most technical publications. Here’s a few of those schools:

Theoretical Advanced Study Institute in Elementary Particle Physics (TASI)

École de Physique des Houches (often simply “Les Houches”)

Mainz Institute of Theoretical Physics (MITP) Summer School

The Coordinated Theoretical-Experimental Project on QCD (CTEQ) Summer School