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Archive for the ‘Seminars’ Category


NPP Seminar by Dimitri Kharzeev (SUNY Stony Brook)

March 15th, 2015 by geurts

Date: Tuesday  March 24, 2015 at noon
Location: 223 Herman Brown Hall, Rice University

Title: The chiral magnetic effect: from quark-gluon plasma to Dirac semimetals, and back
Speaker: Dimitri Kharzeev (SUNY Stony Brook)
Abstract:
Chirality (“handedness”) is an ubiquitous concept in modern science, from particle physics to biology. Recently it has been realized that chirality has dramatic implications for the macroscopic behavior of systems with chiral particles.
In particular, the imbalance between the densities of left- and right-handed fermions in the presence of magnetic field induces the non-dissipative transport of electric charge (“the Chiral Magnetic Effect”, CME) analogous to superconductivity. In quark-gluon plasma, this leads to the charge asymmetry studied in the experiments at Relativistic Heavy Ion Collider and the Large Hadron Collider.
Chirality defines the unique properties of recently discovered Dirac semimetals. I will report the observation of CME in a Dirac semimetal ZrTe5, and discuss the implications for heavy ion experiments.

NPP Seminar by Grant Webb (BNL)

March 10th, 2015 by geurts

Date: Tuesday  March 17, 2015 at noon
Location: 223 Herman Brown Hall, Rice University

Title: Exploring the Gluon Spin Structure of the Proton using the STAR Detector at RHIC
Speaker: Grant Webb (BNL)
Abstract:
After 20 years of experimental efforts the individual parton (quarks and gluons) con- tributions to the spin of the nucleon has not been solved. Precise measurements in po- larized deep inelastic scattering clearly indicate that the spin of the nucleon cannot be explained by the contribution of the quarks alone. The polarized proton-proton collider at RHIC provides direct access to the gluon spin distribution through longitudinal double spin asymmetry measurements of inclusive jets, pions, and dijets. The STAR detector, with its full azimuthal coverage, grants excellent jet reconstruction capabilities. This presentation will focus on the methods used to determine the polarization of the proton beams required to extract any spin dependent result. In addition, the jet reconstruction process and the recent spin results from STAR will be discussed and the impact they have on constraining the gluon spin contribution to the proton’s spin.

NPP Seminar by Bora Akgun (Rice)

February 12th, 2015 by geurts

Date: Thursday March 12, 2015  at 4pm
Location: 223 Herman Brown Hall, Rice University

Title: CMS pixel detector phase-1 upgrade
Speaker: Bora Akgun (Rice)
Abstract:
The CMS pixel detector is at the centre of the CMS experiment and is made of three barrel layers and four endcap disks. It is essential for the reconstruction of track seeds and secondary vertices.  The CMS experiment is going to upgrade its pixel detector during Run 2 of the Large Hadron Collider.
The new detector will provide an additional tracking layer and increased rate capability, suitable for the projected instantaneous luminosities of Run 2, well beyond the original design targets of the present pixel detector.

NPP Seminar by Mandy Rominsky (Fermilab)

January 24th, 2015 by geurts

Date: Tuesday February 17, 2015  at noon
Location: 223 Herman Brown Hall, Rice University

Title: The New g-2 Experiment at Fermilab
Speaker: Mandy Rominsky (Fermilab)
Abstract:
The measurement of the anomalous magnetic moment of the muon provides a test of the standard model and a handle on physics beyond the standard model. There is currently a 3 sigma discrepancy between theory and experiment. With 20 times the statistics and a factor of 4 improvement in the systematic errors, a new experiment at Fermilab aims to resolve this difference. In this talk I’ll discuss the experiment and our recent progress.

NPP Seminar by Xiaodong Jiang (LANL)

October 25th, 2014 by geurts

Date: Tuesday November 4, 2014 at noon
Location: 223 Herman Brown Hall, Rice University

Title: Left-right bias in high energy polarized e+n, p+p and p+A collisions
Speaker:Xiaodong Jiang (LANL)

Abstract: Over the last three decades, large single-spin asymmetries have been observed in high energy polarized p?+p?hadron+X reactions on transversely polarized protons. According to perturbative QCD, this type of parity-conserving left-right asymmetry should be very small if produced from collinear quarks. However, when transverse momentum is considered, single-spin asymmetries can be generated either through quarks` angular motion or through transverely polarized quarks’ fragmentation processes. In the last decade, similar single-spin asymmetry phenomena have also been observed in semi-inclusive deep-inelastic scattering (e+N??e’+h+X), and very recently in inclusive hadron productions (e+N??h+X), on transversely polarized targets.I will describe recent experimental results and introduce upcoming transverse single-spin asymmetry measurements for polarized target Drell-Yan production at Fermilab (E1039, p+p? ?mu+mu- X), and for prompt photon and neutral pion productions in p?+p and p?+A collisions with the PHENIX experiment at RHIC

NPP Seminar by Kuver Sinha (Syracuse Univ.)

October 20th, 2014 by geurts

Date: Wednesday October 29, 2014 at noon
Location: 227 Herman Brown Hall, Rice University

Title: Cosmology as a Probe of Physics Beyond the Standard Model in 2014
Speaker:Kuver Sinha (Syracuse Univ.)
Abstract: Cosmological observations provide clear evidence that the Universe is made up mainly of dark matter and dark energy, neither of which have an explanation within the Standard Model of particle physics. Moreover, inflation, our best theory for primordial structure formation and the vastness of the universe, remains elusive from the point of view of a microscopic theory. Combined with the mysterious hierarchical distance between the Electroweak scale and the Planck scale, and the question of understanding the Higgs mass, it is clear that the cosmic and energy frontiers are both crying out for new physics. Will Nature be kind enough to make new physics accessible to our experiments? I will talk about my latest research, located at the confluence of these areas, and address some of these fundamental questions in the light of new experimental anomalies seen in both frontiers this year.

NPP Seminar by Mark Strikman (PSU)

October 15th, 2014 by geurts

Date: Tuesday  October 21, 2014 at noon
Location: 223 Herman Brown Hall, Rice University

Title: Transverse Geometry of the Hard and Soft pp and pA Collisions at the LHC
Speaker: Mark Strikman (PSU)

Abstract: Decades of studies of hard QCD phenomena provided a precision picture of the distribution of proton constituents (quarks and gluons) over the fraction of energy, x, which they carry in fast nucleons. More recently, studies of the hard exclusive processes provided first information about three dimensional structure of fast nucleons – the x-dependent impact parameter single parton distributions in the nucleon and led to the two scale geometric picture of the proton – proton interactions at the LHC. I will review how this picture explains a number of regularities of hadron production observed at the LHC, and reveals presence of the parton – parton correlations in nucleons. I will also present evidence for existence of significant fluctuations of gluon strength in nucleons as well as fluctuations of the overall strength of the interactions and discuss implications for pp and pA collisions.

NPP Seminar by Carlos Ordonez (UH)

April 25th, 2014 by geurts

Date: Thursday Wednesday May 1, 2014 at 1h30pm
Location: 200 Brockman Hall for Physics, Rice University

Title:  A pedagogical introduction to anomalies in conformal quantum mechanics and some potential applications in cold-atom and graphene systems
Speaker: Carlos Ordonez (UH)
Abstract: The breaking of a classical symmetry at the quantum level as a consequence of the quantization procedure is known as an anomaly (quantum). Anomalies in quantum field theory (chiral, gauge) have a long history and their impact in particle and gravitational physics (including strings) is well known.  Anomalies in quantum mechanics (non-relativistic systems) also exist, although they are not as well-known.  I will describe how these anomalies arise in systems described by conformal quantum mechanics (CQM), following the work of my group at UH. I will also mention some recent applications to cold atoms and possible applications to graphene physics.  The latter is very recent.  The first half of the talk will be dedicated to showing in detail how the anomalies arise in the concrete case of a two-dimensional delta function potential. There rest of the talk will emphasize the (possible) applications.  The emphasis of the talk will be on the conceptual aspects and it will be pedagogical in nature. My hope is that people in the audience (from high-energy, condensed-matter and AMO-physics backgrounds) will find this topic interesting and of potential use in their research.

NPP Seminar by Regina Demina (Rochester)

April 10th, 2014 by geurts

Date: Wednesday April 16, 2014 at noon
Location: 223 Herman Brown Hall, Rice University

Title:  Asymmetry in production of top quarks
Speaker: Regina Demina (Rochester)
Abstract: Results from the Tevatron experiments suggest that there is a forward-backward asymmetry in the production of the top and antitop quarks, namely the top quark is emitted preferentially in the direction of the initial proton. I will review the latest results on the asymmetry measurement from the Tevatron. Kinematic dependencies of these asymmetries are discussed. I will also comment on the consistency of the Tevatron and LHC data.

NPP Seminar by Peter Onyisi (UT Austin)

April 2nd, 2014 by geurts

Date: Tuesday  April 8, 2014 at noon
Location: 223 Herman Brown Hall, Rice University

Title: Latest Top-Higgs Coupling Results from ATLAS
Speaker: Peter Onyisi (UT Austin)
Abstract: The Yukawa coupling of the Higgs boson to the top quark is one of the fundamental parameters of the Standard Model, and its size probes whether the electroweak symmetry breaking mechanism and the fermion mass generation mechanism are the same.  Indirect measurements of this quantity – determined from Higgs production via top quark loops – are available, but suffer from ambiguity with possible new physics in the loop diagrams.  In contrast we can constrain the Yukawa coupling with tree diagrams using the cross-section of associated production of the Higgs boson with a top quark pair (ttH).  I will discuss the latest ATLAS seaches for ttH production in the H -> gamma gamma and H -> bb decays and some projections for the future.