Dr. Guennadi Borissov

(also known as Gennady Borisov)

 

        Contact information

 

            Physics Department

            Lancaster University

            Lancaster LA1 4YB, UK

 

            E-mail:  gvborissov@googlemail.com

            Phone:   +44-1524-594612

            Fax:       +44-1524-844037

            Office:   B16, Physics Building

 

 

 

Plain English summary

 

The articles in Fermilab Today  give a very good description of my results intended for people not familiar with Particle Physics:

 

·    October 10, 2008 Expecting the unexpected (Charge asymmetry in semileptonic decays);

·    February 28, 2008 New mixing in the standard recipe? (CP violation in Bs → J/ψφ);

·    October 4, 2007 An identity crisis (Bs oscillation);

·    June 14, 2007  A new member of the standard model zoo (Ξb discovery);

·    May 31, 2007  The difference between even and odd (Decay Bs→DsDs);

·    September 14, 2006  Why antimatter does not matter (CP violation in semileptonic Bs decays);

·    March 16, 2006  The magical mix of B mesons  (Flavor tagging of Bd);

·    March 6, 2006  My Wine & Cheese seminar at Fermilab (B** and CP violation in di-muon events);

·    October 13, 2005  DZero Measures Life of Orbitally Excited Mesons (B →μνD** studies);

·    April 29, 2004    DZero B- and B0 Decays Get the Chance of a Lifetime (Lifetime difference of B0 and B+);

·    February 19, 2004  B Stars on Ice  (B** studies);

·    December 18, 2003  DZero Examines True Nature of New Particle (X(3872) particle, the first result obtained with BANA package);

 

 

Scientific Biography (updated 10 February 2009)

 

I received my PHD in 1995 from the Institute for High Energy Physics (Protvino, Russia). The subject of my thesis was “Measurement of the  with the DELPHI experiment at LEP”. This measurement published in Phys.Lett. provides a very precise test of the Standard Model. During few following years I worked in French laboratories within the DELPHI experiment. I developed the method of b-quark tagging, i.e. the selection of events with b-quark among many other events. This method was used as a common tool within DELPHI and was applied in many measurements with b-quark. The most important result obtained with this method, in which I contributed directly, was the lower limit on the Standard Model Higgs boson. Some other results with my direct contribution are: the search for technicolor particles and the study of  process.

 

Selected results of DELPHI experiment with my direct contribution:

·    Combined b tagging (Journal Server), Nucl.Instrum.Meth. A417, 384 (1998);

·    b tagging in DELPHI at LEP (PDF), Eur.Phys.J. C32, 185 (2004);

·    Fine tuning of track impact parameter resolution of the DELPHI detector (Journal Server), Nucl.Instrum.Meth. A372, 181 (1996);

·    A Precise measurement of the partial decay width ratio R(b)**0 = Gamma(b anti-b) / Gamma(had) (Compressed PostScript), Eur.Phys.J., C10, 415 (1999);

·    ZZ production in e+ e- interactions at s**(1/2) = 183-GeV to 209-GeV (PDF), Eur.Phys.J. C30, 447 (2003);

·    Final results from DELPHI on the searches for SM and MSSM neutral Higgs bosons (PDF),  Eur.Phys.J. C32, 145 (2004);

·    Search for technicolor with DELPHI (PDF), Eur.Phys.J. C22, 17 (2001);

·    Search for the standard model Higgs boson at LEP in the year 2000 (PDF), Phys.Lett. B499 (2001);

 

Other interesting results of DELPHI obtained using my method of b tagging (but without my direct participation):

 

·    Measurement of the rate of b anti-b b anti-b events in hadronic Z decays and the extraction of the gluon splitting into b anti-b (Journal Server), Phys.Lett.B 462, 425 (1999);

·    Determination of A**b(FB) at the Z pole using inclusive charge reconstruction and lifetime tagging (PDF), Eur.Phys.J. C40, 1 (2005);

·    Determination of the b quark mass at the M(Z) scale with the DELPHI detector at LEP (PDF), Eur. Phyis. J. C46, 569 (2006);

 

I came to Lancaster in 2001 and simultaneously joined the Dzero experiment at Tevatron (Fermilab, USA). For this experiment I developed the software program of track reconstruction, which finds the trajectories of all charged particles in event. In parallel, I developed the method of alignment of the tracking system, which is used to determine the position of all tracking detectors. In parallel with these two projects, and in direct connection with them, I developed the software package (BANA) for the physics analysis of events with b quarks. Almost all results in B physics obtained by the Dzero collaboration in RunII were based on this package. I personally, or together with the supervised students, or together with a small group of other primary authors, obtained the following results:

 

·    Measurement of the ratio of B+ and B0 meson lifetimes,  hep-ex/0410052, PRL 94, 182001 (2005), Plain English Summary;

·    Measurement of semileptonic branching fractions of B mesons to narrow D** states, hep-ex/0507046, PRL 95, 171803 (2005), Plain English Summary;

·    Direct Limits on the Bs0 Oscillation Frequency , hep-ex/0603029, PRL 97, 021802 (2006) , Plain English Summary;

·    Measurement of B_d mixing using opposite-side flavor tagging , hep-ex/0609034, PRD 74, 112002 (2006);

·    Measurement of the charge asymmetry in semileptonic B_s decays , hep-ex/0701007, PRL 98, 151801 (2007);

·    Direct Observation of the Strange b Baryon Xi_b^- , hep-ex/0706.1690, PRL 99, 052001 (2007) ;

·    Combined D0 Measurements Constraining the CP-Violating Phase and Width Difference in the B_s System , hep-ex/0702030, PRD 76, 057101 (2007) ;

·    Measurement of the Lambda_b Lifetime using Semileptonic Decays , hep-ex/0706.2358, Phys. Rev. Lett. 99, 182001 (2007);

·    Observation and Properties of L=1 B_1 and B_2* (B**) Mesons , hep-ex/0705.3229, PRL 99, 172001 (2007) ;

·    Observation and Properties of the Orbitally Excited Bs2* Meson, arXiv.org:0711.0319 ,  Phys. Rev. Lett. 100, 082002 (2008) ;

·    Measurement of the branching fraction Br(Bs->Ds* Ds*) , hep-ex/0702049, Phys. Rev. Lett. 99, 241801 (2007);

·    Study of Direct CP Violation in B±→J/ψK±(π±) Decays, arXiv.org:0802.3299, Phys. Rev. Lett. 100, 211802 (2008);

·    Measurement of the Bs0 Mixing Parameters from the Flavor-Tagged Decay Bs0→J/ψφ, arXiv.org:0802.2255, Phys. Rev. Lett. 101, 241801 (2008);

 

My current research interests are related with the study of the CP violation. The CP violation is a key ingredient to explain the baryon asymmetry of the Universe, or in simple words, why there is no any antimatter in our Universe, and only objects containing the matter are present. The related results obtained so far in this direction:

 

·    Measurement of the branching fraction Br(Bs->Ds* Ds*) , hep-ex/0702049, Phys. Rev. Lett. 99, 241801 (2007);

·    Measurement of the charge asymmetry in semileptonic B_s decays , hep-ex/0701007, PRL 98, 151801 (2007);

·    Study of Direct CP Violation in B±→J/ψK±(π±) Decays, arXiv.org:0802.3299, Phys. Rev. Lett. 100, 211802 (2008);

·    Measurement of the Bs0 Mixing Parameters from the Flavor-Tagged Decay Bs0→J/ψφ, arXiv.org:0802.2255, Phys. Rev. Lett. 101, 241801 (2008);

·    Combined D0 Measurements Constraining the CP-Violating Phase and Width Difference in the B_s System, hep-ex/0702030, PRD 76, 057101 (2007);

 

I am also a member of the ATLAS collaboration and expect to gradually increase my involvement in this experiment. In particular, I want to select and explore new heavy objects decaying to the final states containing the top quark. My current activities within ATLAS:

 

·    Development of the AAna - general-purpose analysis package for ATLAS experiment (together with James Catmore and James Walder).

·    Development of procedure to measure and monitor the beam spot (together with James Walder).