Recent Results From The CMS Experiment

Recent Results From The CMS Experiment

Taylan Yetkin

Yıldız Teknik Üniversitesi

Fizik Bölümü

Özet/Abstract : Since the beginning of this year the CMS Experiment at LHC has been collecting data from 8 TeV center of mass energy proton-proton collisions. The science community was eagerly expecting updated results on Higgs boson search after the first results shown in 2011. With the jointly held meeting on July 4th 2012, ATLAS and CMS experiments announced the observation of a new boson with mass around 125 GeV. By using 2012 data, other studies have also been carried out for exotic and supersymmetric physics, which perhaps did not resonate with scientific community as much as the Higgs search did.In this talk, after describing the current status of data taking at CMS, I will discuss the recent results from the CMS experiment, covering standard model Higgs

boson, exotic and supersymmetric searches. Due to large number of studies I will concentrate only on a few analyses, pointing out their reflections on theoretical studies. During the talk I will also explain several key plots on the significance that are commonly used in collider physics analysis.



Yer : MSGSÜ Bomonti Binası, Fizik Bölümü.
Tarih : 18 Ekim  2012 Perşembe, 15:00
Ayrıntılı bilgi :

Critical nature of plastic flow

Critical nature of plastic flow

Oguz Umut Salman

Ecole Polytechnique Paris

Özet/Abstract : Steady plastic flows have been compared to developed turbulence because the two phenomena share the inherent complexity of particle trajectories, the scale free spatial patterns and the power law statistics of fluctuations. The presence of power law distributions has been interpreted as a sign of criticality, marginal stability and scale free behavior of the underlying microscopic systems. In this talk we present a simple mathematical model which is capable of generating power law signals with critical exponents matching observations. Our main conclusion is the existence of a discrete automaton behind the conventional continuum mechanical equations.

Yer : MSGSÜ Bomonti Binası, Fizik Bölümü.
Tarih : 11 Ekim 2012 Perşembe, 15:00

The tasks and perspectives of stringy theory of knots

The tasks and perspectives of stringy theory of knots

Alexei Morozov

ITEP Moscow

04.10.2012 Thursday/Perşembe 15:00

Place/Yer : MSGSÜ Bomonti Binası, Fizik Bölümü.
İnfo/Bilgi :

Acoustic superradiance from a vortex in Bose – Einstein condensates

Acoustic superradiance from a vortex in Bose – Einstein condensates

Nader Ghazanfari

Koç University, Physics Dept., İstanbul

27.09.2012 Thursday/Perşembe 15:00

Özet/Abstract : Unruh’s efforts to make a connection between propagation of sound in non-homogenous media and propagation of light in curved space time resulted in surprising systems appropriate for studying different features of the black holes such as spontaneous radiation and stimulated emissions. Acoustic superradiance is the analogue of Penrose process as a stimulated emission which is the extraction of energy from a rotating black hole. This process occurs in curved spacetime that is the geometry of rotating black holes. Event horizon in such a spacetime exists inside a region called ergoregion, and since the rotating energy of the black hole is located in between event horizon and ergosphere the extracting of energy becomes possible. In other words, in this process, the wave solution of the field equation is scattered from ergo region with an increase in its amplitude. Vortex geometry could be a nice analogue of a black hole in order to observe Penrose process since it reveals an effective ergo region which is also simple to be achieved is experiments.

Place/Yer : MSGSÜ Bomonti Binası, Fizik Bölümü.
İnfo/Bilgi :

Perturbative construction of QED using ERG

Perturbative construction of QED using ERG

Hidenori Sonoda

Kobe University Physics Dept.

13.09-2012 Thursday / Perşembe 15:00

Özet / Abstract : I would like to explain how to use the exact renormalization group (Wilson-Polchinski differential equation) to construct QED perturbatively.  I first introduce the necessary tools using a real scalar theory as a concrete example.  I then explain how to construct QED by imposing the Ward-Takahashi identity to the solution of the ERG differential equation.  I end the talk by deriving the Khalatnikov-Landau equation for the gauge parameter dependence of the correlation functions.

Place/Yer : MSGSÜ Bomonti Binası, Fizik Bölümü.
İnfo/Bilgi :

Cosmology in nonlinear massive gravity

Cosmology in nonlinear massive gravity

A. Emir Gümrükçüoğlu
Kavli IPMU, University of Tokyo

06-09-2012 Perşembe/Thursday 15:00

Özet/Abstract : General theory of relativity, in which the interactions have an infinite range, is in agreement with current experimental and observational data. On the other hand, from a theorist’s point of view, it is an interesting question whether the range of gravity can be consistently made to be finite, or equivalently, whether graviton can have a non-zero mass. This has been one of the most persistent challenges in classical field theory for the last 70 years. Recently, de Rham, Gabadadze and Tolley constructed a nonlinear theory of massive gravity, which successfully avoids the complications encountered before. Moreover, the theory has also phenomenological relevance, since the graviton mass may account for the accelerated expansion of the present universe, providing an alternative to dark energy. I will present self-accelerating cosmological solutions in the framework of this theory. The cosmological perturbations around these background have an interesting behaviour: instead of the 5 degrees of freedom expected from a massive spin-2 field, only the 2 gravity wave polarizations are dynamical, at linear level. However, nonlinear analysis of the extra modes reveal the existence of ghost instabilities. This implies that a consistent universe solution in this theory should be inhomogeneous and/or anisotropic.

Yer : MSGSÜ Bomonti Binası, Fizik Bölümü.
Tarih : 6 Eylül 2012 Perşembe, 15:00