Physicists searching for the elusive Higgs boson are expected to share new findings July 4
Tuesday, July 3, 2012

Anticipating a major announcement July 4 from scientists at the Large Hadron Collider (LHC)—the world's largest atom smasher located at the European Organization for Nuclear Research (CERN) in Geneva, Switzerland—University of Iowa researchers are available for interviews by news media.

LHC scientists are expected to comment on progress toward finding evidence of the Higgs boson. The elusive particle is named for Scottish physicist Peter Higgs, who helped develop a model explaining how particles acquire different masses. The model predicts the existence of a particle whose discovery would help scientists understand the origin of mass.

The UI professors, all from the College of Liberal Arts and Sciences Department of Physics and Astronomy and members of LHC research groups, are:

• Usha Mallik (319-335-0499,, leader of the UI’s ATLAS team

• Yasar Onel, (319-335-1853, and Jane Nachtman (630-631-9200,, leaders of the UI’s CMS team

The UI CMS group, in addition to Onel and Nachtman, includes Emeritus Professors Ed Norbeck and Ed McCliment, Adjunct Assistant Professor Ugur Akgun, Project Scientist J.P. Merlo, two research scientists, two post-doctoral fellows, eleven graduate students, two engineers, and four undergraduate students.

Since 1993, Onel and colleagues have played a key LHC role by contributing a particle detector designed and developed at UI machine shops. Today, the device is part of the LHC's Compact Muon Solenoid (CMS) collision hall.

Members of the Iowa group led the installation, commissioning, and data-taking operations efforts on CMS, and are now contributing to data analysis, including the latest results being presented at international physics meetings, in particular the International Conference on High Energy Physics this week in Australia.

Iowa research scientist Kai Yi leads a search for exotic physics decaying to jets, sprays of particles originating from a quark or gluon. His analysis takes advantage of the CMS calorimeter to precisely measure their energy and position, allowing him to isolate anomalous events. His search looks beyond the Higgs boson to the unexpected physics that may be indicated by these exotic collisions.

Other Iowa analysis efforts search for new physics predicted by models such as Supersymmetry and heavy neutrinos. The Iowa group also continues to contribute to the daily operation of the CMS detector.

UI research scientist Taylan Yetkin has been stationed at CERN for several years and is a key part of the operations team. The facility requires a crew of highly-trained and dedicated individuals, as the complex, one-of-a-kind detectors are operated remotely in the LHC tunnel and must function at a high level for months without intervention.

The UI ATLAS experiment group, in addition to Mallik, includes postdoctoral fellows Remi Zaidan, Garabed Halladjian, Yuriy Pylypchenko, and graduate student Reddy Pratap Gandrajula.

Since joining the ATLAS experiment in late 2006 (after completing the CP-violation, matter-antimatter experiment BABAR at the Stanford Linear Accelerator Center) the group has been a major contributor to the 80-million-channel, high-resolution, Pixel sub-detector that is the closest to the interaction point and critical for finding the collision point (vertex reconstruction).

The Iowa group was instrumental in preparing online codes for calibration of the sub-detector and the in-situ cosmic ray tests. They now are responsible for constructing part of an upgrade to be completed in 2013.

The Iowa group also was instrumental in the first publication from the ATLAS experiment in 2010, which established the operation of tracking and vertexing software with real data for the first time. They are actively engaged in the search for the Higgs boson decay into a b and an anti-b quark.

Additional information about the search for the Higgs in the United States at the Fermilab’s Tevatron, the world’s second-most powerful particle accelerator, may be found on the Fermilab website.