Pekka K. Sinervo

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Pekka K. Sinervo is an experimental particle physicist who has studied quarks, [1] gluons [2] and vector bosons [3] [4] [5] [6] using high-energy electron and proton collisions. He is a professor of physics at University of Toronto, where he has taught and pursued research since 1990.

He is known for his contributions to the discovery of the top quark [7] and studies of its properties (see, e.g., [8] [9] [10] ), along with collaborators in the CDF (Collider Detector at Fermilab) and ATLAS experiments. He was also a member of one of the teams that discovered the Higgs boson. [11] His earlier work involved the study of mesons with charm quarks and strange quarks, and hadrons with bottom quarks (see, e.g., [12] [13] [14] ). He is currently working on searches for new particles (see, e.g., [15] [16] ) and dark matter [17] at the SNOLAB Underground Laboratory, as a member of the SuperCDMS Collaboration. [18] Sinervo served as dean of the Faculty of Arts and Science at the University of Toronto [19] from 2003 to 2008, and as senior vice-president, research at the Canadian Institute for Advanced Research [20] from 2009 to 2015. He has written on international research collaborations, science and Judaism, and popular science (see, e.g.,

[21] [22] ). He is a member of the Reform Jewish Community of Canada, [23] serving as its president from 2017 to 2021, and has served in leadership roles in the Union for Reform Judaism [24] and the World Union for Progressive Judaism. [25] He has been recognized for his contributions with appointments to numerous scientific societies [Note 1] with fellowships in the American Physical Society and the Royal Society of Canada recognizing his contributions to the discovery of the top quark. He was appointed a member of the Order of Canada in 2018 [26] for his contributions to the discoveries of the top quark and Higgs boson, and his leadership in the Canadian Jewish community.

Notes

  1. Fellowships in the American Physical Society, Royal Society of Canada, American Association for the Advancement of Science and Massey College.

Related Research Articles

<span class="mw-page-title-main">Gluon</span> Elementary particle that mediates the strong force

A gluon is a type of massless elementary particle that mediates the strong interaction between quarks, acting as the exchange particle for the interaction. Gluons are massless vector bosons, thereby having a spin of 1. Through the strong interaction, gluons bind quarks into groups according to quantum chromodynamics (QCD), forming hadrons such as protons and neutrons.

<span class="mw-page-title-main">Standard Model</span> Theory of forces and subatomic particles

The Standard Model of particle physics is the theory describing three of the four known fundamental forces in the universe and classifying all known elementary particles. It was developed in stages throughout the latter half of the 20th century, through the work of many scientists worldwide, with the current formulation being finalized in the mid-1970s upon experimental confirmation of the existence of quarks. Since then, proof of the top quark (1995), the tau neutrino (2000), and the Higgs boson (2012) have added further credence to the Standard Model. In addition, the Standard Model has predicted various properties of weak neutral currents and the W and Z bosons with great accuracy.

<span class="mw-page-title-main">Charm quark</span> Type of quark

The charm quark, charmed quark, or c quark is an elementary particle found in composite subatomic particles called hadrons such as the J/psi meson and the charmed baryons created in particle accelerator collisions. Several bosons, including the W and Z bosons and the Higgs boson, can decay into charm quarks. All charm quarks carry charm, a quantum number. This second-generation particle is the third-most-massive quark, with a mass of 1.27±0.02 GeV/c2 as measured in 2022, and a charge of +2/3 e.

<span class="mw-page-title-main">Top quark</span> Type of quark

The top quark, sometimes also referred to as the truth quark, is the most massive of all observed elementary particles. It derives its mass from its coupling to the Higgs boson. This coupling yt is very close to unity; in the Standard Model of particle physics, it is the largest (strongest) coupling at the scale of the weak interactions and above. The top quark was discovered in 1995 by the CDF and DØ experiments at Fermilab.

The bottom quark, beauty quark, or b quark, is an elementary particle of the third generation. It is a heavy quark with a charge of −1/3 e.

<span class="mw-page-title-main">Tetraquark</span> Exotic meson composed of four valence quarks

In particle physics, a tetraquark is an exotic meson composed of four valence quarks. A tetraquark state has long been suspected to be allowed by quantum chromodynamics, the modern theory of strong interactions. A tetraquark state is an example of an exotic hadron which lies outside the conventional quark model classification. A number of different types of tetraquark have been observed.

<span class="mw-page-title-main">J/psi meson</span> Subatomic particle made of a charm quark and antiquark

The
J/ψ
(J/psi) meson is a subatomic particle, a flavor-neutral meson consisting of a charm quark and a charm antiquark. Mesons formed by a bound state of a charm quark and a charm anti-quark are generally known as "charmonium" or psions. The
J/ψ
is the most common form of charmonium, due to its spin of 1 and its low rest mass. The
J/ψ
has a rest mass of 3.0969 GeV/c2, just above that of the
η
c
, and a mean lifetime of 7.2×10−21 s. This lifetime was about a thousand times longer than expected.

<span class="mw-page-title-main">UA2 experiment</span> Particle physics experiment at CERN

The Underground Area 2 (UA2) experiment was a high-energy physics experiment at the Proton-Antiproton Collider — a modification of the Super Proton Synchrotron (SPS) — at CERN. The experiment ran from 1981 until 1990, and its main objective was to discover the W and Z bosons. UA2, together with the UA1 experiment, succeeded in discovering these particles in 1983, leading to the 1984 Nobel Prize in Physics being awarded to Carlo Rubbia and Simon van der Meer. The UA2 experiment also observed the first evidence for jet production in hadron collisions in 1981, and was involved in the searches of the top quark and of supersymmetric particles. Pierre Darriulat was the spokesperson of UA2 from 1981 to 1986, followed by Luigi Di Lella from 1986 to 1990.

A conformal anomaly, scale anomaly, trace anomaly or Weyl anomaly is an anomaly, i.e. a quantum phenomenon that breaks the conformal symmetry of the classical theory.

<span class="mw-page-title-main">Two-photon physics</span> Branch of particle physics concerning interactions between two photons

Two-photon physics, also called gamma–gamma physics, is a branch of particle physics that describes the interactions between two photons. Normally, beams of light pass through each other unperturbed. Inside an optical material, and if the intensity of the beams is high enough, the beams may affect each other through a variety of non-linear effects. In pure vacuum, some weak scattering of light by light exists as well. Also, above some threshold of this center-of-mass energy of the system of the two photons, matter can be created.

<span class="mw-page-title-main">Exotic hadron</span> Subatomic particles consisting of quarks and gluons

Exotic hadrons are subatomic particles composed of quarks and gluons, but which – unlike "well-known" hadrons such as protons, neutrons and mesons – consist of more than three valence quarks. By contrast, "ordinary" hadrons contain just two or three quarks. Hadrons with explicit valence gluon content would also be considered exotic. In theory, there is no limit on the number of quarks in a hadron, as long as the hadron's color charge is white, or color-neutral.

This is a timeline of subatomic particle discoveries, including all particles thus far discovered which appear to be elementary given the best available evidence. It also includes the discovery of composite particles and antiparticles that were of particular historical importance.

<span class="mw-page-title-main">Flavor-changing neutral current</span>

In particle physics, flavor-changing neutral currents or flavour-changing neutral currents (FCNCs) are hypothetical interactions that change the flavor of a fermion without altering its electric charge.

<span class="mw-page-title-main">Drell–Yan process</span> Process in high-energy hadron–hadron scattering

The Drell–Yan process occurs in high energy hadron–hadron scattering. It takes place when a quark of one hadron and an antiquark of another hadron annihilate, creating a virtual photon or Z boson which then decays into a pair of oppositely-charged leptons. Importantly, the energy of the colliding quark-antiquark pair can be almost entirely transformed into the mass of new particles. This process was first suggested by Sidney Drell and Tung-Mow Yan in 1970 to describe the production of lepton–antilepton pairs in high-energy hadron collisions. Experimentally, this process was first observed by J. H. Christenson et al. in proton–uranium collisions at the Alternating Gradient Synchrotron.

<span class="mw-page-title-main">DØ experiment</span> Particle physics research project (1983–2011)

The DØ experiment was a worldwide collaboration of scientists conducting research on the fundamental nature of matter. DØ was one of two major experiments located at the Tevatron Collider at Fermilab in Batavia, Illinois. The Tevatron was the world's highest-energy accelerator from 1983 until 2009, when its energy was surpassed by the Large Hadron Collider. The DØ experiment stopped taking data in 2011, when the Tevatron shut down, but data analysis is still ongoing. The DØ detector is preserved in Fermilab's DØ Assembly Building as part of a historical exhibit for public tours.

CLEO was a general purpose particle detector at the Cornell Electron Storage Ring (CESR), and the name of the collaboration of physicists who operated the detector. The name CLEO is not an acronym; it is short for Cleopatra and was chosen to go with CESR. CESR was a particle accelerator designed to collide electrons and positrons at a center-of-mass energy of approximately 10 GeV. The energy of the accelerator was chosen before the first three bottom quark Upsilon resonances were discovered between 9.4 GeV and 10.4 GeV in 1977. The fourth Υ resonance, the Υ(4S), was slightly above the threshold for, and therefore ideal for the study of, B meson production.

In particle physics phenomenology, chiral color is a speculative model which extends quantum chromodynamics (QCD), the generally accepted theory for the strong interactions of quarks. QCD is a gauge field theory based on a gauge group known as color SU(3)C with an octet of colored gluons acting as the force carriers between a triplet of colored quarks.

In particle physics, W′ and Z′ bosons refer to hypothetical gauge bosons that arise from extensions of the electroweak symmetry of the Standard Model. They are named in analogy with the Standard Model W and Z bosons.

<span class="mw-page-title-main">Luigi Di Lella</span> Italian experimental particle physicist

Luigi Di Lella is an Italian experimental particle physicist. He has been a staff member at CERN for over 40 years, and has played an important role in major experiments at CERN such as CAST and UA2. From 1986 to 1990 he acted as spokesperson for the UA2 Collaboration, which, together with the UA1 Collaboration, discovered the W and Z bosons in 1983.

Color transparency is a phenomenon observed in high-energy particle physics, where hadrons created in a nucleus propagate through that nucleus with less interaction than expected. It suggests that hadrons are first created with a small size in the nucleus, and then grow to their nominal size. Here, color refers to the color charge, the property of quarks and gluons that determines how strongly they interact through the nuclear strong force.

References

  1. Gell-Mann, M. (1 February 1964). "A Schematic Model of Baryons and Mesons". Phys. Lett. 8 (3): 214. Bibcode:1964PhL.....8..214G. doi:10.1016/S0031-9163(64)92001-3.
  2. Soding, P. (26 April 2010). "On the Discovery of the Gluon" (PDF). The European Physical Journal H. 35 (1): 3. Bibcode:2010EPJH...35....3S. doi:10.1140/epjh/e2010-00002-5. S2CID   8289475.
  3. Arnison, G.; et al. (24 February 2003). "Experimental observation of isolated large transverse energy electrons with associated missing energy at sqrt(s) = 540 GeV". Phys. Lett. 122B: 103. doi:10.1016/0370-2693(83)91177-2.
  4. Banner, M.; et al. (17 March 2003). "Observation of single isolated electrons of high transverse momentum in events with missing transverse energy at the CERN proton-antiproton collider". Phys. Lett. 122B: 476. doi:10.1016/0370-2693(83)91605-2.
  5. Arnison, G.; et al. (5 July 2003). "Experimental observation of lepton pairs of invariant mass around 95 GeV/c2 at the CERN SPS collider". Phys. Lett. 126B (5): 398. doi:10.1016/0370-2693(83)90188-0.
  6. Bagnaia, P.; et al. (15 September 2003). "Evidence for Z0→e+e− at the CERN proton-antiproton collider". Phys. Lett. 129B: 130. doi:10.1016/0370-2693(83)90744-X.
  7. Abe, F.; et al. (3 April 1995). "Observation of Top Quark Production in Proton-Antiproton Collisions with the Collider Detector at Fermilab". Phys. Rev. Lett. 74 (14): 2626–2631. arXiv: hep-ex/9503002 . doi:10.1103/PhysRevLett.74.2626. PMID   10057978.
  8. Abe, F.; et al. (20 August 2001). "Measurement of the Top Quark Pt Distribution in Proton-Antiproton Collisions at sqrt(s)=1.8 TeV". Phys. Rev. Lett. 87 (10): 102001. doi:10.1103/PhysRevLett.87.102001. hdl: 1969.1/183004 . PMID   11531473.
  9. Abe, F.; et al. (19 January 2006). "Precision Top Quark Mass Measurement in the Lepton + Jets Topology in Proton-Antiproton Collisions at sqrt(s) = 1.96 TeV". Phys. Rev. Lett. 96 (2): 022004. arXiv: hep-ex/0510049 . doi:10.1103/PhysRevLett.96.022004. hdl:1969.1/178529. PMID   16486564. S2CID   119351771.
  10. Aad, G.; et al. (7 February 2012). "Measurement of the top quark-pair production cross section with ATLAS in pp collisions at sqrt(s)=7 TeV in dilepton final states with ATLAS". Phys. Lett. B. 707: 459. arXiv: 1108.3699 . doi:10.1016/j.physletb.2011.12.055.
  11. Aad, G.; et al. (7 September 2012). "Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC". Phys. Lett. B. 716 (1): 1. arXiv: 1207.7214 . Bibcode:2012PhLB..716....1A. doi:10.1016/j.physletb.2012.08.020.
  12. Ushida, N.; et al. (29 September 1980). "Measurement of the D0 Lifetime". Phys. Rev. Lett. 45 (13): 1049. doi:10.1103/PhysRevLett.45.1049.
  13. Aston, D.; et al. (13 December 1984). "Phys. Lett. B Observation of Two Non-leading Strangeness-one Vector Mesons". Phys. Lett. 149B: 258. doi:10.1016/0370-2693(84)91595-8. OSTI   1447163.
  14. Abe, F.; et al. (1 December 1996). "Ratios of Bottom Meson Branching Fractions Involving J/psi Mesons and Determination of b Quark Fragmentation Fractions". Phys. Rev. D. 54 (11): 6596–6609. arXiv: hep-ex/9607003 . Bibcode:1996PhRvD..54.6596A. doi:10.1103/PhysRevD.54.6596. PMID   10020669.
  15. Abe, F.; et al. (19 June 2000). "Search for a W′ Boson via the Decay Mode W′→μνμ in 1.8 TeV proton-antiproton Collisions". Phys. Rev. Lett. 84 (25): 5716–5721. arXiv: hep-ex/9910004 . doi:10.1103/PhysRevLett.84.5716. PMID   10991038.
  16. Aad, G.; et al. (25 May 2022). "Search for single production of a vectorlike T quark decaying into a Higgs boson and top quark with fully hadronic final states using the ATLAS detector". Phys. Rev. D. 105 (9): 092012. arXiv: 2201.07045 . Bibcode:2022PhRvD.105i2012A. doi:10.1103/PhysRevD.105.092012.
  17. Cham, Jorge; Whiteson, Daniel (2017). We Have No Idea. New York: Riverhead Books. ISBN   9780735216631.
  18. Albakry, M.F.; et al. (30 June 2023). "Search for low-mass dark matter via bremsstrahlung radiation and the Migdal effect in SuperCDMS". Phys. Rev. D. 107 (11): 112013. arXiv: 2302.09115 . Bibcode:2023PhRvD.107k2013A. doi:10.1103/PhysRevD.107.112013.
  19. Brown, Craig (2013). Arts and Science at Toronto: A History 1827-1990. Toronto: University of Toronto Press. p. 339. ISBN   978-1-4426-4513-4.
  20. Brown, Craig (2007). A Generation of Excellence. Toronto: University of Toronto Press. p. 352. ISBN   978-0-8020-9232-8.
  21. P. Sinervo; D. Therien (2013). Baron, B.; Amrhein, C. (eds.). Building success in a global university : government and academica - redefining the relationship around the world. Bonn: Lemmens Medien. p. 296. ISBN   9783868560084.
  22. Sinervo, P. (26 April 2018). "Confessions of a Jewish Physicist". Sinai and Synapses. Retrieved 25 February 2024.
  23. "Reform Jewish Community of Canada" . Retrieved 25 February 2024.
  24. "Union for Reform Judaism" . Retrieved 25 February 2024.
  25. "World Union for Progressive Judaism" . Retrieved 25 February 2024.
  26. Governor General of Canada. "Recipients Order of Canada" . Retrieved 25 February 2024.