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At the LHC, lead ions are smashed together at high speeds, creating quark-gluon plasma (QGP), a unique state of matter where quarks and gluons are free from confinement in protons and neutrons, similar to ice melting into water in QED. The QGP lasts only 10^-22 seconds, making it difficult to probe directly. However, high-energy quarks and gluons from collisions form jets, which are narrow cones of particles. Scientists study how jets are modified when passing through QGP, such as energy loss and deflection.

Boleslaw “Bolek” Wyslouch PhD ’87, professor of physics and director of the Laboratory for Nuclear Science and Bates Research and Engineering Center, is elected to American Academy of Arts and Sciences for 2023. He is one of the founders and leaders of the heavy ion program in the CMS experiment, one of the large, multipurpose particle detectors at LHC.

Following the observation of long-range correlation signal in pp collisions with CMS collaboration, the ALICE Collaboration presented new results on observing the ridge structure, a long-range correlation of produced particles, in low-multiplicity proton-proton (pp) collisions at the Large Hadron Collider (LHC) at the 57th Rencontres de Moriond international conference.

On Friday, 18 November, a test using collisions of lead ions was carried out in the Large Hadron Collider (LHC) and provided an opportunity for the experiments to validate the new detectors and new data-processing systems ahead of next year’s lead-lead physics run. In this test run, the center-of-mass energy of the lead-lead collisions delivered by the LHC reached 5.36 TeV for the first time! This also marks the first heavy-ion collision since December 2018 at the end of the LHC Run 2.

When Yen-Jie Lee came to MIT as a graduate student in 2006, it was a bit of a culture shock. The aspiring particle physicist had studied physics at National Taiwan University before his career took a hiatus in the forested mountains of Taiwan. There, he worked as a marine corps lieutenant to fulfill the nation’s required military service. He still remembers the deafening crackle of artillery drills and the unyielding pressure of daily military life.

Brand new, state-of-the-art components for an upgraded 1000-ton particle detector are being installed at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory. Known as sPHENIX, the detector is a radical makeover of the PHENIX experiment, which first began taking data at the Lab’s Relativistic Heavy Ion Collider (RHIC) in 2000. The sPHENIX upgrade will significantly enhance scientists’ ability to learn about quark-gluon plasma (QGP), an exotic form of nuclear matter created in RHIC’s energetic particle smashups.

The 10th edition of the Hard and Electromagnetic Probes International Conference series was hosted as an online conference from June 1st until June 5th 2020 due the to coronavirus pendamic over the world. Everyone in the MIT Heavy Ion Group connected to the meeting and many of them presented the latest results for CMS and sPHENIX experiments in the meeting. We have given 5 parallel talks online. All students attened the online student lecture on May 31. The next day, in the afternoon of June 1, our almuni Chris McGinn gave a presentation on his work at MIT entitled “Measurement of Jet Nuclear Modification Factors with Large-R with the CMS Detector“. Next, Molly reoprted the CMS photon-jet correlations results “Study of in-medium momentum broadening with photon-jet momentum correlations in PbPb collisions at 5.02 TeV with the CMS experiment“.