The CMS at CERN
My research currently revolves around the Compact Muon Solenoid at CERN. I am currently serving as the CMS Physics Co-coordinator. The CMS features nearly complete solid-angle coverage and can precisely measure electrons, photons, muons, jets and missing energy over a large range of particle energies. The BU group at the CMS are making significant contributions to physics analyses involving searches for new particles.
“The CMS Trigger system”, CMS Collaboration, JINST 12 (2017) no.01, P01020, arXiv:1609.02366
"Search for W' to tb in proton-proton collisions at sqrt(s) = 8 TeV", CMS Collaboration, JHEP 02 (2016) 122.
“Search for top-quark partners with charge 5/3 in the same-sign dilepton final state”, CMS Collaboration, Phys. Rev. Lett. 112 112 171801 (2014)
“Search for a W′ or Techni-rho decaying into WZ in pp Collisions at sqrt(s) = 7 TeV”, CMS Collaboration, Phys. Rev. Lett 109 (2012) 071803.
"Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC", CMS Collaboration, Phys. Lett. B 716 (2012) 30.
For a full list of publications, please see the attached CV.
- B.A. Cambridge University, U.K.
- Ph.D. Columbia University
Tulika Bose is an Associate Professor of Physics at Boston University and is currently serving a two-year term as the Physics Coordinator for the CMS experiment. She received her B.A. from Cambridge University where she worked as an undergraduate on the measurement of the W mass at the OPAL experiment at CERN. Her Ph.D. research at Columbia University focused on a search for Bs oscillations at D0 and led to the first double-sided bound on the oscillation frequency in 2006. She helped install and commission the D0 Silicon Track Trigger and served as the onsite operations coordinator. Her post-doctoral research at Brown University focused on direct searches for new phenomena at the D0 and CMS experiments. She served as an on-call expert for the D0 data acquisition system and helped design and optimize the first trigger menus for CMS. She joined Boston University as an Assistant Professor in 2008 and played a lead role in the commissioning of the CMS High-Level Trigger during the 7 and 8 TeV runs. As the CMS Trigger Coordinator during the start up of the 13 TeV run, she had overall responsibility for the operation of the trigger and for ensuring that CMS collected the necessary datasets for both discovery and precision physics. Her physics interests on CMS include precision measurements of diboson cross sections and searches for new heavy gauge bosons and top quark partners. She has served as the convener of the CMS Beyond 2 Generations physics group and also as the subgroup convener of the CMS Standard Model Diboson Group. Her work has been recognized by a prestigious Alfred P. Sloan fellowship and a CMS Distinguished Researcher award. Bose has a keen interest in outreach and has given many public lectures and interviews and also organized various events reaching out to high school students. She has served as a member of the Fermilab Users' Executive Committee and also the US LHC Users Association Executive Committee. She is currently a member of the APS Division of Particles and Fields (DPF) Executive Committee.
- Sloan Research Fellow
- Trigger Coordinator of the Compact Muon Solenoid (CMS) Experiment
- Physics Coordinator of the Compact Muon Solenoid (CMS) Experiment
In the news:
- Clint Richardson wins CMS Achievement Award
- Local students get a lesson in high energy physics
- Clint Richardson awarded 2014 CMS Fundamental Physics Scholarship
- Tulika Bose talks trigger systems and new physics with BU
- CERN experiments observe particle consistent with long-sought Higgs boson
- Prof. Tulika Bose awarded Sloan Research Foundation Fellowship
- Lane, Bose, Black referenced in Daily Free Press
- Bose appointed CMS Physics Coordinator
Higgs Detection at The Compact Muon Solenoid Detector at the Large Hadron Collider
The Compact Muon Solenoid (CMS) is a 14 kiloton detector designed to search for new physics at an unprecedented distance scale of 10-19 m at the CERN Large Hadron Collider (LHC). The detector consists of 220 square meters of silicon pixels and strips (80 million channels) for precision charged particle tracking, 75k lead-tungsten crystals for precision electron and photon measurements, a highly segmented 1000-ton brass hadron-calorimeter plus a quartz-fiber forward calorimeter to measure jets from quark and gluon scattering and energy balance, all surrounded by precision muon chambers embedded in the return yoke of the magnet. Overall, the detector features nearly complete solid-angle coverage and can precisely measure electrons, photons, muons, jets and missing energy over a large range of particle energies. These broad capabilities of the CMS detector allow the exploration of electroweak symmetry breaking and will enable the potential discovery of physics beyond the Standard Model.
The CMS trigger and data acquisition systems are responsible for ensuring that physics-enriched data samples with potentially interesting events are recorded with high efficiency and good quality. The experiment has a two-level trigger system, unlike most other hadron collider experiments that have more traditional three-level systems. The first physical level is hardware-based and is called the “Level-1 Trigger” (L1) while the second physical level is software-based and is called the “High-Level Trigger” (HLT). L1 uses information from the calorimeters and muon detectors and is designed to select, in less than 1 ms, the most interesting events starting from a total input (collision) rate of about 40 MHz. The HLT processor farm further decreases the event rate from around 100 kHz to around 400 Hz, before data storage. The trigger system, therefore, has to provide a high selectivity of ~10-5 with respect to the active LHC bunch crossings while ensuring that the ability to select rare, exotic events is preserved. Boston University has played a leading role in the coordination of the CMS Trigger effort with Bose serving as the CMS Trigger Coordinator (2014-2016) and as the CMS Deputy Trigger Coordinator (2011-2013). Group members were involved in the design and commissioning of the CMS HLT and continued to spearhead the effor thereaftert. Many of the BU personnel resident at CERN served as HLT on-call experts during the LHC Run 1 (Avetisyan, Carerra, Fantasia and Sperka) and Run 2 (Avetisyan, Rankin, Richardson).
The collision rate at the LHC also presents enormous technical challenges on the design of readout electronics due to the intense radiation environment and the high speed at which millions of channels of data must be processed. The Boston University group has a leadership role in calorimeter electronics and related software (Rohlf and Sulak). The group has designed and built the data concentrator, a sophisticated piece of digital electronics based on modern field programmable gate arrays (FPGAs) to read out the hadron calorimeter. Group members have also led the custom design of the 18-channel hybrid photo-diode used to convert scintillation light from the calorimeter into electrical signals. We have also designed the electronics to feed calorimeter signals into the muon trigger to greatly reduce the backgrounds in the online event selection. Members of the BU CMS team have also helped design the two hadronic forward calorimeters which are positioned at either end of the CMS detector, to pick up the myriad particles coming out of the collision region at shallow angles relative to the beam line. Group members also play a key role in the day-to-day operation of the calorimeter.
The Boston University collaborators (Bose, Rohlf, and Sulak, their postdocs Girgis and Pinna, and their grad students, with their engineers Eric Hazen and Shouxiang Wu) are reaping the physics benefits of our investment in detector hardware, trigger and algorithm development. Group members are making significant contributions to physics analyses involving searches for new particles and the hunt for the Higgs Boson. These analyses include (among many others) searches for heavy gauge bosons and exotic WZ resonances. We are also playing a leading role in the study of diboson production; the latter is critical for increasing the sensitivity of our Higgs searches and thereby help understand the mechanism of electroweak symmetry breaking.
Bose has served as the co-convener of the Electroweak Diboson group (2011), co-convener of the Resonances group within the Beyond Two Generations physics group (2012-2014), and co-convener of the Beyond Two Generations group (2016-2017). She is currently serving a two-year term as CMS Physics Co-coordinator (2017-2019). Sulak serves on the Advisory Board of the Hadron Calorimeter, and manages some 15 undergraduates as Director of the BU/CERN/DOE Internship Program.
The DØ Experiment
The DØ experiment studies proton-antiproton collisions at the world’s highest energy accelerator, the Fermilab Tevatron. These collisions release energy equivalent to 2000 times the proton mass. The DØ detector is a large, highly sophisticated instrument that measures the fragments of these collisions and allows scientists to study the structure of matter at these high energies. According to our current understanding, the basic constituents of matter are quarks and leptons. All the matter surrounding us is made of the lightest quarks, called up and down, and the lightest leptons, the electron and its neutrino. However there exist two additional families of quarks and leptons with identical properties, except much larger masses. The heaviest of the quarks, the "top" quark, was discovered in 1995 by the DØ and CDF collaborations at Fermilab. The top quark turned out to have an extraordinarily large mass, approximately the same as an entire gold atom. Particle physicists believe that its further study will provide clues to the origins of mass. The members of the Boston University DØ group were actively involved in the discovery of the top quark and the study of the carrier of the weak force, the "W boson". The group is now participating in the second data-taking run which began in 2001 and will continue until 2009. During this run, thousands of top quarks will be created, allowing a detailed study of the properties of this intriguing particle. The data from the Fermilab Tevatron will also provide the best opportunity until the LHC begins operation to find the Higgs boson and new physics beyond the standard model. The Boston University group has taken leadership roles in the construction of the muon detector system and the silicon microstrip tracker, the development of algorithms to identify bottom quarks and muons, and the "Top and Higgs Physics" analysis group. The group has designed and built a significant fraction of the electronics for the muon system trigger, the silicon track trigger, and the central fiber tracker trigger. The group’s physics interests center on the top quark and the search for new particles and forces beyond the standard model.