This page is always under development ! And not always up to date :-)

Ta strona poswiecona jest mojej dzialalnosci naukowej
Dzialalnosc dydaktyczna omowiona jest na osobnej stronie

See also my dedicated public talks and presentations page.

What I am working on...

  • Construction of the EUDET pixel telescope,
  • Contact Interaction analysis of ZEUS 1994-2007 data,
  • Photon Collider beam simulation with CAIN.


  • Previous analysis (completed)

  • Higgs production at the Photon Collider,
  • CompAZ: parametrization of the energy spectra for gamma-gamma collider at TESLA (dedicated page),
  • Contact Interaction analysis of ZEUS 1994-2000 data,
  • New physics at THERA,
  • Leptoquark searches at TESLA,
  • Leptoquark searches at future experiments,
  • Global leptoquark analysis,
  • Global eeqq contact interaction analysis,
  • Old high Q2 and exotic searches at ZEUS.
  • For more information and links have a look at:
  • Home Page of Warsaw ILC group
  • Home Page of the ZEUS Collaboration
  • ZEUS BAC Group home page at DESY
  • Home page of the Pi of the Sky experiment

  • EUDET pixel telescope

  • A.F.Zarnecki, P.Niezurawski,
    EUDET Telescope Geometry and Resolution Studies
    EUDET-Report-2007-01,
    [physics/0703058]
  • For more results see also: public talks and presentations.

    Contact Interaction analysis of ZEUS 1994-2007 data

    Preliminary results based on 1994-2005 data were submitted to ICHEP'2006.
    More details can be found on the CI analysis page (ZEUS members only)


    Photon Collider beam simulation with CAIN

    For more results see also:
    public talks and presentations.

    Higgs studies at Photon Collider

    Production of the Higgs boson at the Photon Collider at ILC is studied for the SM and MSSM Higgs bosons. For light SM higgs and MSSM higgs decay to b-quarks is considered. For heavy SM higgs (above 160 GeV) we consider decays to WW and ZZ. Simulation of signal and background processes takes into account higher order corrections, realistic luminosity spectra and detector effects. Expected precision of the higgs two-photon-width measurement is estimated. For heavy SM higgs large interference effects are expected in the WW decay channel. By reconstructing WW and ZZ final states not only the h->gamma+gamma partial width but also the relative phase of the scattering amplitude can be measured. Measurement of the angular distributions for secondary WW and ZZ decays can be used to study CP properties of the Higgs boson.

    Published results:
  • M.Spira, P.Niezurawski, M.Krawczyk, A.F.Zarnecki,
    Heavy neutral MSSM Higgs Bosons at the PLC - a comparison of two analyses
    Proceedings of Linear Collider Workshop (LCWS06), Banagalore, India, 9-13 Mar 2006,
    [hep-ph/0612369]

  • E. Accomando et al.
    Workshop on CP Studies and Non-Standard Higgs Physics
    [hep-ph/0608079]

  • P.Niezurawski, A.F.Zarnecki, M.Krawczyk,
    Simulation of the Higgs boson production at LHC, ILC and photon linear collider.
    Proceedings of PLC'2005, Acta Phys.Polon.B37:1173-1179,2006

  • P.Niezurawski, A.F.Zarnecki, M.Krawczyk,
    LHC wedge at the PLC: Observability of gamma gamma ---> A, H ---> b anti-b.
    Proceedings of PLC'2005, Acta Phys.Polon.B37:1187-1191,2006,

  • LHC/LC Study Group
    Physics interplay of the LHC and the ILC.
    Phys.Rept.426:47-358,2006, [hep-ph/0410364]

  • P.Niezurawski, A.F.Zarnecki, M.Krawczyk,
    Determination of the Higgs-boson couplings and H-A mixing in the generalized SM-like Two Higgs Doublet Model
    JHEP 0502:041,2005. [hep-ph/0403138]

  • P.Niezurawski, A.F.Zarnecki, M.Krawczyk,
    Model-Independent Determination of CP Violation from Angular Distributions in Higgs Boson Decays to WW and ZZ at the Photon Collider
    Acta Phys.Polon.B36:833-844,2005. [hep-ph/0410291]

  • P.Niezurawski, A.F.Zarnecki, M.Krawczyk,
    Study of the Higgs boson decays into W+ W- and ZZ at the photon collider.
    JHEP 0211:034,2002. [hep-ph/0207294]

  • P.Niezurawski, A.F.Zarnecki, M.Krawczyk,
    The SM Higgs boson production gamma gamma ---> h ---> b anti-b at the photon collider at TESLA.
    Acta Phys.Polon.B34:177-188,2003. [hep-ph/0208234]

  • For more results see also: public talks and presentations.

    Contact Interaction analysis of ZEUS 1994-2000 data

    Analysis completed.
    ZEUS Collaboration paper "Search for contact interactions, large extra dimensions and finite quark radius in ep collisions at HERA" , DESY-03-218, Phys.Lett. B591 (2004) 23-41
    [hep-ex/0401009]


    New physics at THERA

    Results contributed to the
    THERA appendix of the TESLA TDR .

    The sensitivity of THERA to different contact interaction models has been studied in detail. For models conserving parity, scales up to about 18 TeV can be probed at THERA, extending considerably beyond the existing bounds. Significant improvement of existing limits is also expected for models with large extra dimensions. Effective Plank mass scales up to about 2.8 TeV can be probed. THERA will be the best machine to study leptoquark properties, for leptoquark masses up to about 1 TeV. It will be sensitive to the leptoquark Yukawa couplings down to ~0.01.

    You can find more details in:

  • Contact Interactions, Large Extra Dimensions and Leptoquarks at THERA , included in THERA Book ,
    published in Acta Physica Polonica B33 (2002) 619.
  • Previous results and talks on Leptoquark searches at future experiments
  • More about physics at THERA:

  • THERA: Electron-Proton Scattering at sqrt(s) ~ 1 TeV Part VI (Appendices),Chapter 2 of the TESLA TDR,
  • THERA web page.

  • Leptoquark Searches at TESLA

    Results contributed to the
    TESLA Technical Design Report (TDR).

    Measurement of the Yukawa couplings of the first-generation leptoquarks has been studied for e+e- collisions at TESLA, at sqrt(s)=800 GeV. By combining measurements from different production and decay channels, determination of Yukawa couplings with precision on the few per-cent level is possible. TESLA will be sensitive to very small leptoquark Yukawa couplings not accessible at LHC, down to ~0.05 e. Distinction between left-handed and right-handed Yukawa couplings is feasible even for leptoquark masses very close to the pair-production kinematic limit.

    You can find more details in:

  • Measurement of the leptoquark Yukawa couplings in e+e- collisions at TESLA , e-print hep-ex/0102043; also available as LC Note LC-PHSM-2001-20 .
  • Previous results and talks on Leptoquark searches at future experiments
  • More about e+e- physics at TESLA:

  • Physics at an e+e- Linear Collider, Part III of TESLA Technical Design Report
  • Collection of Linear Collider notes.

  • Leptoquark Searches at Future Colliders

    Leptoquark searches are considered for future experiments at HERA, Tevatron, LHC, TESLA and THERA. Expected exclusion limits from direct leptoquark searches (leptoquark pair production and single leptoquark production) are compared with indirect limits expected from the contact interaction analysis. Strongest limits on the leptoquark masses and couplings are expected from high luminosity LHC data. If the leptoquark signal suggested by the existing data is detected at LHC, with mass below 1 TeV, TESLA will be an ideal place to study leptoquark properties, provided that the leptoquark Yukawa coupling is not too small.

    You can find more details in:

  • Leptoquark Searches at Future Colliders, e-print hep-ph/0006335, contribution #193 to ICHEP-2000.
  • "Leptoquark Searches in TESLA", talk presented at International Workshop on High Energy Photon Colliders, DESY, Hamburg, June 2000 (see also contribution to proceedings ).
  • "Leptoquark Searches in TESLA", talk presented at ECFA/DESY meeting, Padova, Italy, May 2000.
  • "Leptoquarks and Contact Interactions from Global analysis" talk presented on DIS'2000 in Liverpool, April 2000 (see also contribution to proceedings ).

  • Global Leptoquark Analysis

    Using data from HERA, LEP and the Tevatron, as well as from low energy experiments I try to constrain the Yukawa couplings for scalar and vector leptoquarks in the Buchmuller-Ruckl-Wyler effective model. Some leptoquark models are found to describe the existing experimental data much better than the Standard Model. Assuming that a real leptoquark signal is observed, calculated is an allowed region in the lambda-M plane. The leptoquark signal is mostly resulting from the new data on the atomic parity violation in cesium, but is also supported by recent LEP2 measurements, unitarity violation in the CKM matrix and HERA high-Q2 results.

    You can find more details in:

  • "Leptoquark Signal from Global Analysis", talk presented on ICHEP-2000 in Osaka, July 2000 (see also contribution to proceedings ).
  • Leptoquark Signal from Global Analysis, e-print hep-ph/0003271, published in Euro. Phys. J. C 17 (2000) 695, contribution #125 to ICHEP-2000.
  • "Leptoquarks and Contact Interactions from Global analysis" talk presented on DIS'2000 in Liverpool, April 2000 (see also contribution to proceedings ).

  • Global Contact Interaction Analysis

    Using data from HERA, LEP and the Tevatron, as well as from low energy experiments I try to constrain the scale of possible electron-quark contact interactions. For specific models mass scale limits range up to about 18 TeV. Using the contact interaction framework, I extract limits on possible "new physics" effects at HERA, LEP (TESLA) and the Tevatron.

    You can find more details in:

  • "Leptoquarks and Contact Interactions from Global analysis" talk presented on DIS'2000 in Liverpool, April 2000 (see also contribution to proceedings ).
  • "Contact Interactions and Future Prospects for High Energy Physics" talk presented on EPS HEP'99 in Tampere, July 1999 (see also contribution to proceedings ).
  • Seminar presented in March 1999 at Warsaw (updated June 1999 for presentation at Institute of Physics, Bonn University)
  • Global Analysis of eeqq Contact Interactions and Future Prospects for High Energy Physics, e-print hep-ph/9904334, published in Euro. Phys. J. C11 (1999) 3, 539-557.
  • Contact Interactions: Results from ZEUS and a Global Analysis talk presented on DIS'99 Workshop in Zeuten, April 1999 (see also contribution to proceedings , eprint: hep-ph/9905565).

  • Analysis of ZEUS data 1994-97

    I was involved in the measurement of the High-x/High-Q² NC and CC DIS cross-sections, and in the search for the Lepto-quark production and Contact Interactions.

    Have a look at:
  • "High Q² Events in ep Collisions" - talk presented on DIS'97 Workshop in Chicago (see also contribution to proceedings ).
  • Preliminary ZEUS results on high Q² CC DIS presented at Stony Brook Hadron Collider Workshop on June 10th (1994-96 data).
  • Updated ZEUS results on high Q² CC DIS presented at Leptron-Photon '97 (1995-97 data).
  • Contact Interactions: Results from ZEUS and a Global Analysis talk presented on DIS'99 Workshop in Zeuten, April 1999 (see also contribution to proceedings , eprint: hep-ph/9905565).
  • I was also involved in search for diffractive CC DIS events.

    You can have a look at:
  • Diffractive CC DIS contribution to DIS'96 Workshop proceedings.
  • Diffractive CC DIS contribution to Future Physics at HERA proceedings.
  • Study of diffractive CC DIS selection algorithm - M.Sc. Thesis of Jacek Pliszka (in Polish).