178 research outputs found
A CERN LHC nyaláb luminozitásának abszolĂşt kalibráciĂłja Ă©s a p+p szĂłrás hatáskeresztmetszete a TOTEM kĂsĂ©rletben = Absolute calibration of LHC beam luminosity and determination of total proton - proton cross section in the TOTEM experiment
A kutatási támogatás segĂtsĂ©gĂ©vel kĂ©t fiatal kutatĂł tölthetett mintegy 1 Ă©ves szakmai gyakorlatot a CERN LHC TOTEM kĂsĂ©rletĂ©nĂ©l. Egy egyetemi hallgatĂł pedig elsĹ‘ konferencia kiadványát kĂ©szĂthette el a TOTEM kĂsĂ©rlet Roman Pot detektorainak nyaláb impedancia mĂ©rĂ©sĂ©rĹ‘l. PublikáciĂłs tevĂ©kenysĂ©gĂĽk eredmĂ©nyes munkát takar, Ă©s nem tĂĽkrözi azokat a nehĂ©zsĂ©geket amellyel 2008 szeptemberĂ©ben, az LHC gyorsĂtĂł működĂ©sĂ©nek leállása után kellett szembesĂĽlnĂĽnk, Ă©s amely helyzet várhatĂłan idĂ©n Ă©v vĂ©gĂ©re normalizálĂłdik az LHC ĂşjraindĂtásakor. Az ĂĽtközĹ‘ nyalábok hiánya miatt rĂ©szben át kellett terveznĂĽnk a kutatásokat: azokat a feladatokat soroltuk elĹ‘re, amelyek az Ăşj helyzetben a TOTEM számára a legfontosabbak voltak. RĂ©szt vettĂĽnk a TOTEM Roman Pot detektorok impedanciájának meghatározásában. TeszteltĂĽk a TOTEM RĂłmai FazĂ©k detektorok hatĂ©konyságát . A TOTEM Online AdatgyűjtĹ‘ Ă©s monitorozĂł szoftverĂ©ben Ăşj adatformátumot vezettĂĽnk be. A kĂsĂ©rlet kĂ©rĂ©sĂ©re bekapcsolĂłdtunk a TOTEM Detektor Kontroll Rendszer (DCS) hardver kiĂ©pĂtĂ©sĂ©be is. A tervben szereplĹ‘ teljes hatáskeresztmetszet mĂ©rĂ©st, valamint az LHC nyaláb luminozitásának modell-fĂĽggetlen meghatározását ĂĽktözĂ©sek hĂján, az LHC indulásának csĂşszása miatt nem tudtuk megvalĂłsĂtani, ezekre várhatĂłan a 2009/2010-es akadĂ©miai Ă©vben, az LHC ĂşjraindĂtása után fog majd sor kerĂĽlni, a publikáciĂłk az OTKA támogatásának feltĂĽntetĂ©sĂ©vel jelennek majd meg. | Two young postdocs received a practical training in high energy particle physics in the TOTEM experiment at CERN LHC on this grant. An MSc student completed her first scientific publication on TOTEM Roman Pot detectors. The publications of the participants report on successful research, and does not reflect the difficulties that arised soon after the start of the grant period due to the cessation of the operations of the CERN LHC accelerator in September 2008, a difficult situation that is expected to be normalized only by a successful restart of CERN LHC scheduled presently to the end of 2009. The lack of colliding beams in LHC resulted in a re-scheduling and re-planning of the proposed research: we had to give high priority to those topics that were most important for the TOTEM experiment in this situation. We participated in the beam impedance measurements of the TOTEM Roman Pot subdetectors. We introduced a new data format in the TOTEM online monitoring and data acquisition system. Upon the request of TOTEM we participated in the construction of hardware for the TOTEM Detector Control System. The planned measurement of total cross sections and the absolute calibration of the LHC beam luminosity was postponed due to lack of colliding proton beams and the cessation of LHC operations mentioned above. These measurements will take place after the successfull restart of LHC, expected in the 2009/10 academic year
A new and finite family of solutions of hydrodynamics: Part III: Advanced estimate of the life-time parameter
We derive a new formula for the longitudinal HBT-radius of the two particle
Bose-Einstein correlation function from a new family of finite and exact,
accelerating solution of relativistic perfect fluid hydrodynamics for a
temperature independent speed of sound. The new result generalizes the
Makhlin-Sinyukov and Herrmann-Bertsch formulae and leads to an advanced
life-time estimate of high energy heavy ion and proton-proton collisions
A new and finite family of solutions of hydrodynamics: Part II: Advanced estimate of initial energy densities
We derive a new, exact formula for the estimate of the initial energy
densities from a new family of finite and exact solution of relativistic
perfect fluid hydrodynamics. The new formula depends non-trivially on the speed
of sound and on the shape or width parameter of the measured (pseudo)rapidity
distribution.Comment: Invited talk of G. Kasza at the WPCF 2018 conference in Cracow,
Poland, May 22-26, 2018. Submitted to Acta Physica Polonica
Higher order anisotropies in the Buda-Lund model: Disentangling flow and density field anisotropies
The Buda-Lund hydro model describes an expanding ellipsoidal fireball, and
fits the observed elliptic flow and oscillating HBT radii successfully. Due to
fluctuations in energy depositions, the fireball shape however fluctuates on an
event-by-event basis. The transverse plane asymmetry can be translated into a
series of multipole anisotropy coefficients. These anisotropies then result in
measurable momentum-space anisotropies, to be measured with respect to their
respective symmetry planes. In this paper we detail an extension of the
Buda-Lund model to multipole anisotropies and investigate the resulting flow
coefficients and oscillations of HBT radii.Comment: 1 column format, 20 pages, 10 figure
HBT radii from the multipole Buda-Lund model
The Buda-Lund model describes an expanding hydrodynamical system with
ellipsoidal symmetry and fits the observed elliptic flow and oscillating HBT
radii successfully. The ellipsoidal symmetry can be characterized by the second
order harmonics of the transverse momentum distribution, and it can be also
observed in the azimuthal oscillation of the HBT radii measured versus the
second order reaction plane. The model may have to be changed to describe the
experimentally indicated higher order asymmetries. In this paper we detail an
extension of the Buda-Lund hydro model to investigate higher order flow
harmonics and the triangular dependence of the azimuthally sensitive HBT radii.Comment: 4 pages, 6 figures. Presented at the 11th Workshop on Particle
Correlations and Femtoscopy (WPCF 2015), 03-07 Nov 2015, Warsaw, Polan
A nehézion ütközésekben létrehozott új anyag tulajdonságainak vizsgálata = Investigation of a new form of matter produced in heavy ion reactions
EredmĂ©nyeinket kĂ©t, igen jelentĹ‘s nemzetközi visszhangot kiváltĂł publikáciĂł foglalja mintegy keretbe. Az elsĹ‘ a PHENIX kollaboráciĂł működĂ©sĂ©nek elsĹ‘ 5 Ă©vĂ©t összefoglalĂł munka. Legfontosabb megállapĂtása, hogy a RHIC gyorsĂtĂł Au+Au ĂĽtközĂ©seiben egy Ăşj, igen forrĂł Ă©s sűrű anyagforma jön lĂ©tre, amely a várakozásokkal ellentĂ©tben nem az aszimptotikus szabadság következmĂ©nyekĂ©nt várhatĂł, szinte kölcsönhatás mentes kvarkok Ă©s gluonok gázakĂ©nt, hanem egymással erĹ‘sen kölcsönhatĂł szabadsági fokok folyadĂ©kakĂ©nt viselkedik. Ennek a cikknek Ă©s a tökĂ©letes kvarkfolyadĂ©k felfedezĂ©sĂ©nek kiemelkedĹ‘ sikerĂ©t a kiemelkedĹ‘ számĂş, a zárĂłjelentĂ©s beadásáig beĂ©rkezett 869 hivatkozás is mutatja. A Phys. Rev. Lettersben 2010 elejĂ©n publikált PHENIX-e cikkĂĽnk pedig az elsĹ‘ szakfolyĂłiratban megjelent olyan cikk volt, amely a hadronok lĂ©tezĂ©sĂ©nek határhĹ‘mĂ©rsĂ©kletĂ©t lĂ©nyegesen meghaladĂł 300 MeV-es hĹ‘mĂ©rsĂ©klet Ă©rtĂ©keket közölt szakmai folyĂłiratokban. Ezek az adatok a RHIC-nĂ©l előállĂtott kvark-gluon plazma hĹ‘mĂ©rsĂ©kletĂ©nek elsĹ‘ kĂsĂ©rleti meghatározását jelentik. Ezeket a kĂsĂ©rleti eredmĂ©nyeket rĂ©szletes elmĂ©leti hidrodinamikai publikáciĂłkkal is alátámasztottuk. Számos Ăşj Ă©s alapvetĹ‘ elmĂ©leti eredmĂ©nyt Ă©rtĂĽnk el továbbá a nem-extenzĂv termodinamika elmĂ©letĂ©ben Ă©s nehĂ©zion fizikai alkalmazásaiban, továbbfejlesztettĂĽk az ALCOR Ă©s a Buda-Lund modelleket, Ăşj eredmĂ©nyeket Ă©rtĂĽnk el a kvantum-statisztikus korreláciĂłk Ă©s kvantum-optikai mĂłdszerek nagyenergiás fizikai alkalmazásai terĂĽletĂ©n. | Two renowned papers highlight the main results of this OTKA project. The first paper summarized the results of the first years of PHENIX measurements at RHIC. This paper reported, that in Au+Au collisions at RHIC a new, hot and dense form of matter is created. Expectations suggested that at high temperatures and energy densities a gas of quasi free quarks and gluons will be created. Instead, a fluid phase consisting of strongly interacting quarks and gluons has been observed. This paper and the discovery of a nearly perfect fluid at RHIC received 869 citations by the time of filing this grant report. Another milestone PHENIX paper was published in the Physical Review Letters in early 2010 about the direct photon spectrum in Au+Au collisions at RHIC. For the first time in a refereed scientific journal, initial temperatures of at least 300 MeV were reported. These data indicate the first experimental determination of the initial temperature of the quark-gluon plasma created in Au+Au collisions at RHIC. We have supplemented these results with detailed theoretical publications. We have published fundamental theoretical papers in the theory of non-extensive thermodynamics and its applications in high energy heavy ion physics, we have continued to develop the ALCOR and the Buda-Lund hydrodynamical models, and achieved several new results in the field of quantum-statistical correlations and the applications of quantum-optical methods to the field of high energy physics
Lifetime estimations from RHIC Au+Au data
We discuss a recently found family of exact and analytic, finite and
accelerating, 1+1 dimensional solutions of perfect fluid relativistic
hydrodynamics to describe the pseudorapidity densities and longitudinal
HBT-radii and to estimate the lifetime parameter and the initial energy density
of the expanding fireball in Au+Au collisions at RHIC with
GeV and GeV colliding energies. From these exact solutions of
relativistic hydrodynamics, we derive a simple and powerful formula to describe
the pseudorapidity density distributions in high energy proton-proton and heavy
ion collisions, and derive the scaling of the longitudinal HBT radius parameter
as a function of the pseudorapidity density. We improve upon several
oversimplifications in Bjorken's famous initial energy density estimate, and
apply our results to estimate the initial energy densities of high energy
reactions with data-driven pseudorapidity distributions. When compared to
similar estimates at the LHC energies, our results indicate a surprising and
non-monotonic dependence of the initial energy density on the energy of heavy
ion collisions.Comment: 37 pages, substantially extended and accepted versio
Vadon Ă©lĹ‘ madarak egyes vĂrusfertĹ‘zĂ©seinek vizsgálata = Investigations on certain virus infections of wild birds
A projekt keretĂ©ben vĂ©gzett kutatásaink során kimutattuk a Nyugat-nĂlusi vĂrus (WNV) jelenlĂ©tĂ©t vadmadarak elhullott egyedibĹ‘l (2007.: 3 eset, 2008.: 25 eset, 2009.: 16 eset, 2010.: 3 eset, 2011. augusztusig: 1 eset). MegállapĂtottuk, hogy egyes, kĂĽlönösen Ă©rzĂ©keny ragadozĂł madár fajok (pl. hĂ©ják) mellett a vĂrus Ă©nekes madarakban is elĹ‘fordul. Dokumentáltuk a vĂrus 2008-ban bekövetkezett jelentĹ‘s hazai földrajzi terjedĂ©sĂ©t Ă©s járványos jellegű megjelenĂ©sĂ©t. Járványtani összefĂĽggĂ©seket találtunk a vadmadarakban, emberekben Ă©s lovakban kimutatott, WNV okozta megbetegedĂ©sek között. Magyarországon elsĹ‘kĂ©nt diagnosztizáltunk WNV okozta agyvelĹ‘gyulladást lovakban, valamint bizonyĂtottuk a kĂłrokozĂł jelenlĂ©tĂ©t Culex pipiens szĂşnyogokban. SzerolĂłgiai mĂłdszerekkel WNV ellenes ellenanyagokat mutattunk ki a vizsgált madársavĂłk 26%-ában. Genetikai összehasonlĂtĂł vizsgálatok segĂtsĂ©gĂ©vel megállapĂtottuk, hogy a 2004-ben Magyarországon felbukkant lineage 2 genetikai vonalhoz tartozĂł vĂrustörzs endĂ©miássá vált az országban, majd 2008-ban átterjedt Ausztriába, Ă©s 2010-ben Görögországban is felbukkant. Meghatároztuk Ă©s elemeztĂĽk a hazánkban, 2005-ben felbukkant Usutu vĂrus (USUV) teljes genomszekvenciáját. Nyomon követtĂĽk a vĂrus közĂ©p-eurĂłpai terjedĂ©sĂ©t. Igazoltuk, hogy a Spanyolországban kimutatott USUV eltĂ©r a közĂ©p-eurĂłpai törzstĹ‘l. ElsĹ‘kĂ©nt határoztuk meg a Sedlec bunyavĂrus rĂ©szleges genomszekvenciáját, valamint mutattunk ki madár bornavĂrusokat hazai kĂłresetekbĹ‘l származĂł mintákbĂłl. | Our studies demonstrated the presence of West Nile virus (WNV) in samples of dead birds collected in Hungary (in 2007. 3 cases, in 2008. 25 cases, in 2009. 16 cases, in 2010. 3 cases, and in 2011. until August 1 case). Besides particularly sensitive predatory birds (i.e. goshawks), the virus was detected in several other species, including songbirds. A significant geographic spread and an epidemic of West Nile fever were detected in 2008. in Hungary. Connections were found between the neuroinvasive WNV cases in wild birds, in horses and in humans. WNV-associated encephalitis was diagnosed for the first time in horses in Hungary, and the virus was also detected in Culex pipiens mosquitoes. Anti-WNV antibodies were detected in 26% of the investigated wild bird serum samples using different serological methods. Phylogenetic analyses revealed that the lineage 2 WNV strain, which emerged in Hungary in 2004, became endemic in the country and spread to Austria in 2008. The same strain emerged in Greece in 2010. The complete genome sequence of the Usutu virus (USUV) strain which have emerged in Hungary in 2005 was determined and analyzed. We have monitored the spread of the virus in Central-Europe. Our studies revealed that the USUV strain which was detected in Spain is different from the Central-European strain. Partial genome sequences of the Sedlec bunyavirus were determined for the first time. Avian bornaviruses were detected in samples collected from clinical cases in Hungary
Lifetime Estimations and a Non-Monotonic Initial Energy Density in Heavy Ion Collisions at RHIC and LHC
- …