Pub Date : 2023-11-14DOI: 10.1088/1361-6471/ad0c62
Murat Koksal
Abstract The spontaneous breaking of the $SU(2)_{L}times U(1)_{Y}$ electroweak symmetry of the Standard Model (SM) sets the constraints on triple and quartic gauge couplings. Therefore, the measurement of multiboson production in $e^{-} e^{+}$ collisions allows us to directly test the predictions of the SM and to indirectly probe new physics beyond the SM. In this paper, we focus on the process $e^{-} e^{+} to e^{-} Zgamma e^{+}$ with $Z$ boson decaying into neutrinos to study the anomalous quartic gauge couplings using the effective Lagrangian approach at the Compact Linear Collider (CLIC). We obtain the sensitivities on the anomalous $ f_ {T,i}/Lambda^4$ ($i=0,2,5,6,7,8,9$) couplings taking into account the systematic uncertainties of $3, 5 %$ at $95%$ Confidence Level for the CLIC with $sqrt{s}=3$ TeV. Our results show that the sensitivities on some anomalous couplings without systematic errors are up to two orders of magnitude better than the current experimental limits. Considering a realistic systematic uncertainty such as $5 %$ from possible experimental sources, the sensitivity of all anomalous quartic couplings becomes worse by about $10%$ compared to those without systematic uncertainty for the CLIC.
{"title":"Search for the anomalous quartic gauge couplings through Zγ production at e<sup>-</sup>e<sup>+</sup> colliders","authors":"Murat Koksal","doi":"10.1088/1361-6471/ad0c62","DOIUrl":"https://doi.org/10.1088/1361-6471/ad0c62","url":null,"abstract":"Abstract The spontaneous breaking of the $SU(2)_{L}times U(1)_{Y}$ electroweak symmetry of the Standard Model (SM) sets the constraints on triple and quartic gauge couplings. Therefore, the measurement of multiboson production in $e^{-} e^{+}$ collisions allows us to directly test the predictions of the SM and to indirectly probe new physics beyond the SM. In this paper, we focus on the process $e^{-} e^{+} to e^{-} Zgamma e^{+}$ with $Z$ boson decaying into neutrinos to study the anomalous quartic gauge couplings using the effective Lagrangian approach at the Compact Linear Collider (CLIC). We obtain the sensitivities on the anomalous $ f_ {T,i}/Lambda^4$ ($i=0,2,5,6,7,8,9$) couplings taking into account the systematic uncertainties of $3, 5 %$ at $95%$ Confidence Level for the CLIC with $sqrt{s}=3$ TeV. Our results show that the sensitivities on some anomalous couplings without systematic errors are up to two orders of magnitude better than the current experimental limits. Considering a realistic systematic uncertainty such as $5 %$ from possible experimental sources, the sensitivity of all anomalous quartic couplings becomes worse by about $10%$ compared to those without systematic uncertainty for the CLIC.","PeriodicalId":16770,"journal":{"name":"Journal of Physics G","volume":"21 8","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134953897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-10DOI: 10.1088/1361-6471/ad0b98
Bushra Ali, Shakeel Ahmad, Afzal Ahmad
Abstract Event-by-event fluctuations of multiplicity and transverse momentum of charged hadrons produced in heavy-ion collisions at FAIR energies, 10A, 20A, 30A and 40A GeV are studied in the framework of relativistic transport model, URQMD. Dependence of two families of strongly intensive measures of multiplicity(N) and transverse momentum(pT ) fluctuations, ∆[pT , N] and Σ[pT , N], on collision centrality, centrality bin-widths and pseudorapidity windows are examined. Attempts are also made to study NN, NpT and pT pT fluctuations using two window analysis method. The findings suggest that the measure, ∆[pT , N] be dealt with proper selection of centrality intervals. This measure also exhibits a strong dependence on the widths of η windows. The variable Σ[pT , N], however, is observed to be insensitive to the centrality bin-widths and shows a variation of < 5% with the widths of η windows. The analysis of data after event mixing gives ∆[pT , N] and Σ[pT , N] values asthe widths of η windows and collision centrality, as predicted by model of independent∼ 1 irrespective of emission, IPM. The study of joint fluctuations of the two quantities on two η windows separated in ηof η space, reveals that Σ[NF , NB] values arewindows whereas, the values of Σ[NF, pTB] and Σ[∼p 1 irrespective of the positionTF , pTB] firstly increase with ηsep and later acquire saturations. The observed trend of centrality dependence of Σ[NF , NB], Σ[NF , pTB] and Σ[pTF , pTB] agrees fairly well with those observed in MC simulated studies carried out for AA collisions at LHC energies in the framework model of string fusion.
{"title":"Energy and system size dependence of strongly intensive fluctuation measures in heavy-ion collisions at FAIR energies","authors":"Bushra Ali, Shakeel Ahmad, Afzal Ahmad","doi":"10.1088/1361-6471/ad0b98","DOIUrl":"https://doi.org/10.1088/1361-6471/ad0b98","url":null,"abstract":"Abstract Event-by-event fluctuations of multiplicity and transverse momentum of charged hadrons produced in heavy-ion collisions at FAIR energies, 10A, 20A, 30A and 40A GeV are studied in the framework of relativistic transport model, URQMD. Dependence of two families of strongly intensive measures of multiplicity(N) and transverse momentum(pT ) fluctuations, ∆[pT , N] and Σ[pT , N], on collision centrality, centrality bin-widths and pseudorapidity windows are examined. Attempts are also made to study NN, NpT and pT pT fluctuations using two window analysis method. The findings suggest that the measure, ∆[pT , N] be dealt with proper selection of centrality intervals. This measure also exhibits a strong dependence on the widths of η windows. The variable Σ[pT , N], however, is observed to be insensitive to the centrality bin-widths and shows a variation of < 5% with the widths of η windows. The analysis of data after event mixing gives ∆[pT , N] and Σ[pT , N] values asthe widths of η windows and collision centrality, as predicted by model of independent∼ 1 irrespective of emission, IPM. The study of joint fluctuations of the two quantities on two η windows separated in ηof η space, reveals that Σ[NF , NB] values arewindows whereas, the values of Σ[NF, pTB] and Σ[∼p 1 irrespective of the positionTF , pTB] firstly increase with ηsep and later acquire saturations. The observed trend of centrality dependence of Σ[NF , NB], Σ[NF , pTB] and Σ[pTF , pTB] agrees fairly well with those observed in MC simulated studies carried out for AA collisions at LHC energies in the framework model of string fusion.&#xD;","PeriodicalId":16770,"journal":{"name":"Journal of Physics G","volume":"85 20","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135092414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-08DOI: 10.1088/1361-6471/ad0418
Waseem Ahmad Bhat, M Farooq Mir, Vipul Bairathi, Towseef Ahmad Bhat, Sonia Kabana, Shabir Ahmad Bhat
Abstract Elliptic flow ( v 2 ) of inclusive charged hadrons at mid-rapidity (∣ η ∣ < 1.0) in Au+Au collisions at E lab = 35 A GeV using the parton hadron string dynamics (PHSD) model are presented as a function of centrality, transverse momentum ( p T ) and pseudo-rapidity ( η ). The v 2 results are obtained using the η -sub event plane method with respect to the event plane angle ( ψ 2 ) and participant plane angle ( ψ2PP ). p T -integrated charged hadron v 2 shows a strong centrality dependence in Au+Au collisions at E lab = 35 A GeV. The eccentricity-scaled elliptic flow ( v 2 / ε 2 ) also shows centrality dependence. The higher values of v 2 / ε 2 in central collisions suggest the development of stronger collectivity. The calculations are compared with the results from Au+Au collisions at sNN=7.7GeV published by the STAR experiment at RHIC. We also compare the results of HSD and PHSD modes to investigate the contribution of hadronic and partonic phases of the medium on the calculated v 2 . The current results serve as a prediction of the collective behavior of the matter produced in baryon-rich and moderate temperature conditions for the upcoming multi-purpose detector at the nuclotron-based Ion collider facility (NICA) and compressed baryonic matter experiment at the facility for antiproton and ion research. These predictions are also useful for interpreting data measured at relativistic heavy ion collider (RHIC) beam energy scan program.
{"title":"Elliptic flow of inclusive charged hadrons in Au+Au collisions at E<sub>lab</sub> = 35 A GeV using the PHSD model","authors":"Waseem Ahmad Bhat, M Farooq Mir, Vipul Bairathi, Towseef Ahmad Bhat, Sonia Kabana, Shabir Ahmad Bhat","doi":"10.1088/1361-6471/ad0418","DOIUrl":"https://doi.org/10.1088/1361-6471/ad0418","url":null,"abstract":"Abstract Elliptic flow ( v 2 ) of inclusive charged hadrons at mid-rapidity (∣ η ∣ < 1.0) in Au+Au collisions at E lab = 35 A GeV using the parton hadron string dynamics (PHSD) model are presented as a function of centrality, transverse momentum ( p T ) and pseudo-rapidity ( η ). The v 2 results are obtained using the η -sub event plane method with respect to the event plane angle ( ψ 2 ) and participant plane angle ( <?CDATA ${psi }_{2}^{{PP}}$?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:msubsup> <mml:mrow> <mml:mi>ψ</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> <mml:mrow> <mml:mi mathvariant=\"italic\">PP</mml:mi> </mml:mrow> </mml:msubsup> </mml:math> ). p T -integrated charged hadron v 2 shows a strong centrality dependence in Au+Au collisions at E lab = 35 A GeV. The eccentricity-scaled elliptic flow ( v 2 / ε 2 ) also shows centrality dependence. The higher values of v 2 / ε 2 in central collisions suggest the development of stronger collectivity. The calculations are compared with the results from Au+Au collisions at <?CDATA $sqrt{{s}_{mathrm{NN}}}=7.7,mathrm{GeV}$?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:msqrt> <mml:mrow> <mml:msub> <mml:mrow> <mml:mi>s</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>NN</mml:mi> </mml:mrow> </mml:msub> </mml:mrow> </mml:msqrt> <mml:mo>=</mml:mo> <mml:mn>7.7</mml:mn> <mml:mspace width=\"0.50em\" /> <mml:mi>GeV</mml:mi> </mml:math> published by the STAR experiment at RHIC. We also compare the results of HSD and PHSD modes to investigate the contribution of hadronic and partonic phases of the medium on the calculated v 2 . The current results serve as a prediction of the collective behavior of the matter produced in baryon-rich and moderate temperature conditions for the upcoming multi-purpose detector at the nuclotron-based Ion collider facility (NICA) and compressed baryonic matter experiment at the facility for antiproton and ion research. These predictions are also useful for interpreting data measured at relativistic heavy ion collider (RHIC) beam energy scan program.","PeriodicalId":16770,"journal":{"name":"Journal of Physics G","volume":" 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135293277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-08DOI: 10.1088/1361-6471/ad0417
Mahima Upadhyay, Mahesh Choudhary, Namrata Singh, Aman Gandhi, Aman Sharma, Sumit Bamal, Akash Hingu, Surjit Mukherjee, G Mishra, Sukanya De, L S Danu, Saurav Sood, Sajin Prasad, Ajay Kumar, R G Thomas, Ajay Kumar
Abstract In the present work, we have measured 98 Mo(n, γ ) 99 Mo reaction cross-section using a 7 Li(p,n) 7 Be neutron source at 1.67 ± 0.14, 2.06 ± 0.14 and 2.66 ± 0.16 MeV neutron energies. We have employed offline γ -ray spectroscopy to measure the induced activity of the sample. The 115 In(n,n’ γ ) 115m In reaction was used as a monitor reaction. Different attributes propagating the uncertainty in the total result, measured cross-sections with their uncertainties and correlation coefficients are given in detail in the present study. The result is compared with the data libraries, EXFOR database and theoretical model outcome from different level density models.
{"title":"Measurement of neutron induced reaction cross-section of <sup>99</sup>Mo","authors":"Mahima Upadhyay, Mahesh Choudhary, Namrata Singh, Aman Gandhi, Aman Sharma, Sumit Bamal, Akash Hingu, Surjit Mukherjee, G Mishra, Sukanya De, L S Danu, Saurav Sood, Sajin Prasad, Ajay Kumar, R G Thomas, Ajay Kumar","doi":"10.1088/1361-6471/ad0417","DOIUrl":"https://doi.org/10.1088/1361-6471/ad0417","url":null,"abstract":"Abstract In the present work, we have measured 98 Mo(n, γ ) 99 Mo reaction cross-section using a 7 Li(p,n) 7 Be neutron source at 1.67 ± 0.14, 2.06 ± 0.14 and 2.66 ± 0.16 MeV neutron energies. We have employed offline γ -ray spectroscopy to measure the induced activity of the sample. The 115 In(n,n’ γ ) 115m In reaction was used as a monitor reaction. Different attributes propagating the uncertainty in the total result, measured cross-sections with their uncertainties and correlation coefficients are given in detail in the present study. The result is compared with the data libraries, EXFOR database and theoretical model outcome from different level density models.","PeriodicalId":16770,"journal":{"name":"Journal of Physics G","volume":" 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135293280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-07DOI: 10.1088/1361-6471/ad0a3b
Md Sabir Ali, Muntazir Gull, Kamal Kumar, Tauseef Ahmad, Isar Ahmad Rizvi, Avinash Agarwal, SS Ghugre, Raja Nisar Ali, Faizan Khan
Abstract Measurement of excitation function (EF) of the observed evaporation
residues (ERs) populated in the 20Ne + 93Nb reaction at E_lab ≈ 91-145 MeV were
carried out to explore the systematic of fusion suppression and its dependency on
projectile breakup threshold energy by employing the offline γ-ray detection method.
Excitation function (EF) of the observed ERs populated through complete and/or
incomplete fusion processes were analysed in the framework of statistical mode code
PACE4. Fusion function, derived from experimentally measured fusion cross section,
is compared with the universal fusion function (UFF) to estimate the degree of fusion
incompleteness. Based on the observed results, an empirical formula is proposed here
to interrelate the degree of fusion suppression and breakup threshold energy of the
incident projectile.
{"title":"Systematic of fusion suppression and its dependency on projectile breakup threshold energy","authors":"Md Sabir Ali, Muntazir Gull, Kamal Kumar, Tauseef Ahmad, Isar Ahmad Rizvi, Avinash Agarwal, SS Ghugre, Raja Nisar Ali, Faizan Khan","doi":"10.1088/1361-6471/ad0a3b","DOIUrl":"https://doi.org/10.1088/1361-6471/ad0a3b","url":null,"abstract":"Abstract Measurement of excitation function (EF) of the observed evaporation&#xD;residues (ERs) populated in the 20Ne + 93Nb reaction at E_lab ≈ 91-145 MeV were&#xD;carried out to explore the systematic of fusion suppression and its dependency on&#xD;projectile breakup threshold energy by employing the offline γ-ray detection method.&#xD;Excitation function (EF) of the observed ERs populated through complete and/or&#xD;incomplete fusion processes were analysed in the framework of statistical mode code&#xD;PACE4. Fusion function, derived from experimentally measured fusion cross section,&#xD;is compared with the universal fusion function (UFF) to estimate the degree of fusion&#xD;incompleteness. Based on the observed results, an empirical formula is proposed here&#xD;to interrelate the degree of fusion suppression and breakup threshold energy of the&#xD;incident projectile.","PeriodicalId":16770,"journal":{"name":"Journal of Physics G","volume":"322 9","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135475181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.1088/1361-6471/acffe1
Jesús Ricardo Alvarado García, D Rosales Herrera, P Fierro, Jhony Ramírez, A Fernández Téllez, C Pajares
Abstract In color string models, the transverse momentum distribution (TMD) is obtained through the convolution of the Schwinger mechanism with the string tension fluctuations distribution. Considering a q -Gaussian distribution for these fluctuations, the TMD becomes a hypergeometric confluent function that adequately reproduces the characteristic scales at low and high p T values. In this approach, the hard scale of the TMD is a consequence of considering a heavy-tailed distribution for the string tension fluctuations whose width rises as s , multiplicity or centrality increases. In this paper, we introduce broader information of the TMD in the color string percolation model by determining the color suppression factor, which now also depends on the parameters of the q -Gaussian. To this end, we analyze the reported data on pp and AA collisions at different center of mass energies, multiplicities, and centralities. In particular, for minimum bias pp collisions, we found that the q -Gaussian parameters and the effective temperature are monotonically increasing functions of the center of mass energy. Similar results are found for AA collisions as a function of the centrality at fixed s . We summarize these results in a phase diagram that indicates the q -Gaussian parameters region allowing the quark–gluon plasma formation.
{"title":"Soft and hard scales of the transverse momentum distribution in the Color String Percolation Model","authors":"Jesús Ricardo Alvarado García, D Rosales Herrera, P Fierro, Jhony Ramírez, A Fernández Téllez, C Pajares","doi":"10.1088/1361-6471/acffe1","DOIUrl":"https://doi.org/10.1088/1361-6471/acffe1","url":null,"abstract":"Abstract In color string models, the transverse momentum distribution (TMD) is obtained through the convolution of the Schwinger mechanism with the string tension fluctuations distribution. Considering a q -Gaussian distribution for these fluctuations, the TMD becomes a hypergeometric confluent function that adequately reproduces the characteristic scales at low and high p T values. In this approach, the hard scale of the TMD is a consequence of considering a heavy-tailed distribution for the string tension fluctuations whose width rises as <?CDATA $sqrt{s}$?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:msqrt> <mml:mrow> <mml:mi>s</mml:mi> </mml:mrow> </mml:msqrt> </mml:math> , multiplicity or centrality increases. In this paper, we introduce broader information of the TMD in the color string percolation model by determining the color suppression factor, which now also depends on the parameters of the q -Gaussian. To this end, we analyze the reported data on pp and AA collisions at different center of mass energies, multiplicities, and centralities. In particular, for minimum bias pp collisions, we found that the q -Gaussian parameters and the effective temperature are monotonically increasing functions of the center of mass energy. Similar results are found for AA collisions as a function of the centrality at fixed <?CDATA $sqrt{s}$?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:msqrt> <mml:mrow> <mml:mi>s</mml:mi> </mml:mrow> </mml:msqrt> </mml:math> . We summarize these results in a phase diagram that indicates the q -Gaussian parameters region allowing the quark–gluon plasma formation.","PeriodicalId":16770,"journal":{"name":"Journal of Physics G","volume":"21 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135585437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-02DOI: 10.1088/1361-6471/ad0914
Zhidong Yang, Rainer J. Fries
Abstract Blast wave fits are widely used in high energy nuclear collisions to capture essential features of global properties of systems near kinetic equilibrium. They usually provide temperature fields and collective velocity fields on a given hypersurface. We systematically compare blast wave fits of fluid dynamic simulations for Au+Au collisions at sqrt(s_NN) = 200 GeV and Pb+Pb collisions at sqrt(s_NN) = 2.76 TeV with the original simulations. In particular, we investigate how faithful the viscous blast wave introduced in [1] can reproduce the given temperature and specific shear viscosity fixed at freeze-out of a viscous fluid dynamic calculation, if the final spectrum and elliptic flow of several particle species are fitted. We find that viscous blast wave fits describe fluid dynamic pseudodata rather well and reproduce the specific shear viscosities to good accuracy. However, extracted temperatures tend to be underpredicted, especially for peripheral collisions. We investigate possible reasons for these deviations. We establish maps from true to fitted values. These maps can be used to improve raw fit results from viscous blast wave fits. Although our work is limited to two specific, albeit important, parameters and two collision systems, the same procedure can be easily generalized to other parameters and collision systems.
{"title":"Parameterizing smooth viscous fluid dynamics with a viscous blast wave","authors":"Zhidong Yang, Rainer J. Fries","doi":"10.1088/1361-6471/ad0914","DOIUrl":"https://doi.org/10.1088/1361-6471/ad0914","url":null,"abstract":"Abstract Blast wave fits are widely used in high energy nuclear collisions to capture essential features of global properties of systems near kinetic equilibrium. They usually provide temperature fields and collective velocity fields on a given hypersurface. We systematically compare blast wave fits of fluid dynamic simulations for Au+Au collisions at sqrt(s_NN) = 200 GeV and Pb+Pb collisions at sqrt(s_NN) = 2.76 TeV with the original simulations. In particular, we investigate how faithful the viscous blast wave introduced in [1] can reproduce the given temperature and specific shear viscosity fixed at freeze-out of a viscous fluid dynamic calculation, if the final spectrum and elliptic flow of several particle species are fitted. We find that viscous blast wave fits describe fluid dynamic pseudodata rather well and reproduce the specific shear viscosities to good accuracy. However, extracted temperatures tend to be underpredicted, especially for peripheral collisions. We investigate possible reasons for these deviations. We establish maps from true to fitted values. These maps can be used to improve raw fit results from viscous blast wave fits. Although our work is limited to two specific, albeit important, parameters and two collision systems, the same procedure can be easily generalized to other parameters and collision systems.&#xD;","PeriodicalId":16770,"journal":{"name":"Journal of Physics G","volume":"19 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135874952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The two-particle rapidity correlation among the pions produced in p-p collisions at recent LHC energies √s= 2.76, 5.02, 7 & 13 TeV is studied in this paper by using the analysis of events generated by UrQMD-3.4, AMPT-2.26 & PYTHIA-8.3. Our investigation for bin-to-bin fluctuation using the variance of Forward-Backward asymmetry parameter σC 2 in the forward-backward pseudo-rapidity windows is done through the simulated data. In addition to that, energy-wise variation of correlation strength (β), the probability distribution of roughness parameter (γk 2) and number density fluctuation parameter (dik) are also incorporated in this investigation. Also, we have tried to study the same for textbf{the data of different impact parameters generated using the UrQMD model, and the comparison is made with its minimum biased events data-set. The analysis signifies, that the signature of dynamical fluctuation is not so prominent but increases a bit with the increase in energy. An increase in the correlation strength with the increase in energy signifies the contribution of long-range correlation is more in comparison to the short-range one. However, there is no such accountable effect of various impact parameters seen in the present study.
{"title":"Study of forward-backward correlation and multiplicity fluctuations of pions produced in p-p collisions at recent LHC energies","authors":"Subhadeep Paul, Shreya Bhattacharjee, Azharuddin Ahmed, Tumpa Biswas, Mehedi Kalam, Prabir Kumar Haldar","doi":"10.1088/1361-6471/ad07ed","DOIUrl":"https://doi.org/10.1088/1361-6471/ad07ed","url":null,"abstract":"The two-particle rapidity correlation among the pions produced in p-p collisions at recent LHC energies √s= 2.76, 5.02, 7 & 13 TeV is studied in this paper by using the analysis of events generated by UrQMD-3.4, AMPT-2.26 & PYTHIA-8.3. Our investigation for bin-to-bin fluctuation using the variance of Forward-Backward asymmetry parameter σC\u0000 2 in the forward-backward pseudo-rapidity windows is done through the simulated data. In addition to that, energy-wise variation of correlation strength (β), the probability distribution of roughness parameter (γk\u0000 2) and number density fluctuation parameter (dik) are also incorporated in this investigation. Also, we have tried to study the same for textbf{the data of different impact parameters generated using the UrQMD model, and the comparison is made with its minimum biased events data-set. The analysis signifies, that the signature of dynamical fluctuation is not so prominent but increases a bit with the increase in energy. An increase in the correlation strength with the increase in energy signifies the contribution of long-range correlation is more in comparison to the short-range one. However, there is no such accountable effect of various impact parameters seen in the present study.","PeriodicalId":16770,"journal":{"name":"Journal of Physics G","volume":"552 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136018945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-26DOI: 10.1088/1361-6471/ad074d
Ying Zhang
Abstract A flavor structure with minimal parameters is proposed to address the fermion mass hierarchy and flavor mixing for quarks and leptons. Yukawa interaction is reconstructed in a new basis to show a homological flat structure for up-type quarks, down-type quarks, charged leptons and Dirac neutrinos. A SO(2)^f_{LR} flavor symmetry is found from the hierarchy masses of quarks and leptons, which dominated CKM mixing for quarks and PMNS for leptons. Since the minimal flavor structure successfully addresses CKM and PMNS even in the mass hierarchy limit, mass hierarchy and flavor mixing are two independent questions. As a prediction, a sum rule on the mixing angles and CP violation phase is suggested, which explains the smallness of s13 as a natural result of the mass hierarchy. Generalizing the flat structure to quarks and leptons, a unified Yukawa interaction is achieved for all fermions with only a single coupling.
{"title":"The minimal flavor structure of quarks and leptons","authors":"Ying Zhang","doi":"10.1088/1361-6471/ad074d","DOIUrl":"https://doi.org/10.1088/1361-6471/ad074d","url":null,"abstract":"Abstract A flavor structure with minimal parameters is proposed to address the fermion mass hierarchy and flavor mixing for quarks and leptons. Yukawa interaction is reconstructed in a new basis to show a homological flat structure for up-type quarks, down-type quarks, charged leptons and Dirac neutrinos. A SO(2)^f_{LR} flavor symmetry is found from the hierarchy masses of quarks and leptons, which dominated CKM mixing for quarks and PMNS for leptons. Since the minimal flavor structure successfully addresses CKM and PMNS even in the mass hierarchy limit, mass hierarchy and flavor mixing are two independent questions. As a prediction, a sum rule on the mixing angles and CP violation phase is suggested, which explains the smallness of s13 as a natural result of the mass hierarchy. Generalizing the flat structure to quarks and leptons, a unified Yukawa interaction is achieved for all fermions with only a single coupling.&#xD;","PeriodicalId":16770,"journal":{"name":"Journal of Physics G","volume":"36 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134906984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-26DOI: 10.1088/1361-6471/ad074b
Johan Löfgren
Abstract I argue that the consistency of any resummation method can be established if the method follows a power counting derived from a hierarchy of scales. I.e., whether it encodes a top-down effective field theory. This resolves much confusion over which resummation method to use once an approximation scheme is settled on. And if no hierarchy of scales exists, you should be wary about resumming. I give evidence from the study of phase transitions in thermal field theory, where adopting a consistent power-counting scheme and performing a strict perturbative expansion dissolves many common problems of such studies: gauge dependence, strong renormalization scale dependence, the Goldstone boson catastrophe, IR divergences, imaginary potentials, mirages (illusory barriers), perturbative breakdown, and linear terms.
{"title":"Stop comparing resummation methods","authors":"Johan Löfgren","doi":"10.1088/1361-6471/ad074b","DOIUrl":"https://doi.org/10.1088/1361-6471/ad074b","url":null,"abstract":"Abstract I argue that the consistency of any resummation method can be established if the method follows a power counting derived from a hierarchy of scales. I.e., whether it encodes a top-down effective field theory. This resolves much confusion over which resummation method to use once an approximation scheme is settled on. And if no hierarchy of scales exists, you should be wary about resumming. I give evidence from the study of phase transitions in thermal field theory, where adopting a consistent power-counting scheme and performing a strict perturbative expansion dissolves many common problems of such studies: gauge dependence, strong renormalization scale dependence, the Goldstone boson catastrophe, IR divergences, imaginary potentials, mirages (illusory barriers), perturbative breakdown, and linear terms.","PeriodicalId":16770,"journal":{"name":"Journal of Physics G","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136376199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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