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Öğe B to D(D*)ev(e) transitions at finite temperature in QCD(Amer Physical Soc, 2010) Azizi, Kazem; Er, NurayIn this article, we work out the properties of the B, D, and D* mesons as well as the B -> D(D*)ev(e) decay properties at finite temperature QCD. The behavior of the masses, decay constants and widths of the B, D, and D* mesons in terms of the temperature is studied. The temperature dependency of the form factors responsible for such decays are also obtained. These temperature-dependent form factors are used to investigate the variation of the branching ratios with respect to the temperature. It is shown that the branching ratios do not change up to T/T-c = 0.3, however they start to diminish with increasing the temperature after this region and vanish at the critical or deconfinement temperature.Öğe Effects of a dense medium on parameters of doubly heavy baryons(American Physical Society, 2019) Azizi, Kazem; Er, NurayThe spectroscopic properties of the doubly heavy spin-1/2 baryons Xi(QQ'), Xi(QQ')', Omega(QQ'), and Omega(QQ')', with heavy quarks Q and Q' being b or/and c, are investigated in cold nuclear matter. In particular, the behavior of the mass of these particles with respect to the density of the medium in the range rho is an element of [0, 1.4]rho(sat), with rho(sat) = 0.11(3) GeV3 being the saturation density of nuclear matter, is investigated. From the shifts in the mass and vector self-energy of the states under consideration, it is obtained that Xi(QQ'), and Xi(QQ')', baryons with two heavy quarks and one u or d quark are affected by the medium, considerably. It is also seen that the Omega(QQ'), and Omega(QQ')', states, containing two heavy quarks and one s quark do not see the dense medium, at all. The value of mass for the Xi(cc) state obtained at rho -> 0 limit is nicely consistent with the experimental data. Our results on parameters of other members can be useful in the search for these states. The obtained results may also shed light on the future in-medium experiments aiming to search for the behavior of the doubly heavy baryons under extreme conditions.Öğe Fate of the doubly heavy spin-3/2 baryons in a dense medium(Amer Physical Soc, 2019) Er, Nuray; Azizi, KazemWe investigate the behavior of the doubly heavy spin-3/2 baryons in cold nuclear matter. In particular, we study the variations of the spectroscopic parameters of the ground state Xi(QQ')* and Omega(QQ')* particles, with Q and Q' being b or c quark, with respect to the changes in the density of the nuclear medium. We find the shifts on the parameters under question at saturation medium density compared to their vacuum values. It is observed that the parameters of the Xi(QQ')' states containing two heavy quarks and one up or down quark are affected by the medium, considerably. The parameters of the Omega(QQ')* states containing two heavy quarks and one strange quark, however, do not show any sensitivity to the density of the cold nuclear medium. We also discuss the variations of the vector self-energy at each channel with respect to the changes in the density. The negative shifts in the mass of Xi(QQ')' states due to nucleons in the medium can be used to study the doubly heavy baryons' interactions with the nucleons. The results obtained can also be used in analyses of the results of the future in-medium experiments.Öğe Impact of finite density on spectroscopic parameters of decuplet baryons(Amer Physical Soc, 2016) Azizi, Kazem; Er, Nuray; Sundu, HayriyeThe decuplet baryons, Delta. Sigma*, Xi*, and Omega(-), are studied in nuclear matter by using the in-medium QCD sum rules. By fixing the three-momentum of the particles under consideration at the rest frame of the medium, the negative energy contributions are removed. It is obtained that the parameters of the Delta baryon are more affected by the medium against the Omega-state, containing three strange quarks, whose mass and residue are not considerably affected by the medium. We also find the vector and scalar self-energies of these baryons in nuclear matter. By the recent progresses at the PANDA experiment at the FAIR and NICA facility, it may be possible to study the in-medium properties of such states, even the multistrange. Xi* and Omega-systems, in the near future.Öğe In-medium properties of B and D mesons(E D P Sciences, 2014) Sundu, Hayriye; Azizi, Kazem; Er, NurayThe shifts in the masses and decay constants of B and D mesons in nuclear medium are calculated in the frame work of QCD sum rules. The results obtained are compared with the existing theoretical predictions.Öğe Modifications on parameters of Z(4430) in a dense medium(Elsevier, 2020) Azizi, Kazem; Er, NurayThe charmonium-like resonance Z(c)(3900) and its excited state Z(4430) are among the particles that are serious candidates for double heavy tetraquarks. Calculations of different parameters associated with these states both in the vacuum and the medium with finite density are of great importance. Such investigations help us clarify their nature, internal quark-gluon organization and quantum numbers. In this accordance, we extend our previous analyses on the ground state Z(c)(3900) to investigate the medium modifications on different parameters of the excited Z(4430) state. In particular, we calculate the mass, vector self-energy and current coupling of Z(4430) in terms of density, up to a density comparable to the density of the cores of massive neutron stars. The obtained results may help experimental groups aiming to study the behavior of exotic states at higher densities. (C) 2020 The Author(s). Published by Elsevier B.V.Öğe More about the B and D mesons in nuclear matter(Springer, 2014) Azizi, Kazem; Er, Nuray; Sundu, HayriyeWe calculate the shifts in decay constants of the pseudoscalar B and D mesons in nuclear medium in the frame work of QCD sum rules. We write those shifts in terms of the B-N and D-N scattering lengths and an extra phenomenological parameter entered to calculations. Computing an appreciate forward scattering correlation function, we derive the QCD sum rules for the B-N and D-N scattering lengths and the extra phenomenological parameter in terms of various operators in nuclear medium. We numerically find the values of the shifts in the decay constants compared to their vacuum values. Using the sum rules obtained, we also determine the shifts in the masses of these particles due to nuclear matter and compare the results obtained with the previous predictions in the literature.Öğe The newly observed Zcs(3985)- state: In vacuum and a dense medium(Springer, 2021) Azizi, Kazem; Er, NurayWe report on some properties of the newly observed charged hidden-charmed open strange Zcs(3985)− state by BESIII Collaboration. Assigning the quantum numbers J P = 1+ and the quark composition ccs¯ u¯ and considering it as the strange partner of the famous Zc(3900) state, we estimate the mass of the Zcs(3985)− resonance in vacuum and compare it with the experimental data. We also investigate its mass, current coupling and vector-self energy in a medium with finite density. Our result on the mass in vacuum agrees well with the experimental data. We estimate the mass and current coupling of the b-partner of this state, Zbs, in the vacuum as well. For its mass we get mZbs = 10732+97 −46 MeV, which may be checked via other nonperturbative approaches as well as future experiments. We present the dependence of the spectroscopic parameters of Zcs(3985)− state on density and observe that these parameters are linearly changed with increasing in the density.Öğe Positive and negative parity hyperons in nuclear medium(Amer Physical Soc, 2015) Azizi, Kazem; Er, Nuray; Sundu, HayriyeThe effects of the nuclear medium on the residue, mass, and self-energy of the positive-and negative-parity Sigma, Lambda, and Xi hyperons are investigated using the QCD sum-rule method. In the calculations, the general interpolating currents of hyperons with an arbitrary mixing parameter are used. We compare the results obtained in medium with those of the vacuum and calculate the shifts in the corresponding parameters. It is found that the shifts on the residues in nuclear matter are overall positive for both the positive- and negative-parity hyperons, except for the positive-parity Sigma hyperon which has a negative shift. The shifts on the masses of these baryons are found to be negative. The shifts on the residues and masses of negative-parity states are large compared to those of positive-parity states. The maximum shift belongs to the residue of the negative-parity Lambda hyperon. The vector self-energies gained by the positive-parity baryons are large compared to the vector self-energies of the negative-parity particles. The maximum value of the vector self-energy belongs to the positive-parity Sigma hyperon. The numerical values are compared with the existing predictions in the literature.Öğe Properties of nucleon in nuclear matter : once more(Springer, 2014) Azizi, Kazem; Er, NurayWe calculate the mass and residue of the nucleon in nuclear matter in the frame work of QCD sum rules using the nucleon's interpolating current with an arbitrary mixing parameter. We evaluate the effects of the nuclear medium on these quantities and compare the results obtained with the existing theoretical predictions. The results are also compared with those obtained in vacuum to find the shifts in the quantities under consideration. Our calculations show that these shifts in the mass and residue are about 32 and 15 %, respectively.Öğe Properties of sigma(Q)*, Xi(Q)* and omega(Q)* heavy baryons in cold nuclear matter(Elsevier, 2018) Azizi, Kazem; Er, NurayThe in-medium properties of the heavy spin-3/2 Sigma(Q)*, Xi(Q)*, and Omega(Q)*, baryons with Q being b or c quark are investigated. The shifts in some spectroscopic parameters of these particles due to the saturated cold nuclear matter are calculated. The variations of those parameters with respect to the changes in the density of the cold nuclear medium are studied, as well. It is observed that the parameters of Sigma(Q)* baryons are considerably affected by the nuclear matter compared to the Xi(Q)* and Omega(Q)* particles that roughly do not see the medium. The results obtained may be used in analyses of the data tole provided by the in -medium experiments like PANDA. (C) 2018 Elsevier B.V. All rights reserved.Öğe Properties of Z(c)(3900) tetraquark in a cold nuclear matter(Amer Physical Soc, 2020) Azizi, Kazem; Er, NurayThe study of medium effects on properties of particles embedded in nuclear matter is of great importance for understanding the nature and internal quark-gluon organization as well as exact determination of the quantum numbers, especially of the exotic states. In this context, we study the physical properties of one of the famous charmoniumlike states, Z(c)(3900), in a cold dense matter. We investigate the possible shifts in the mass and current-meson coupling of the Z(c)(3900) state due to the dense medium at saturation density rho(sat) by means of the in-medium sum rules. We also estimate the vector self-energy of this state at saturation nuclear matter density. We discuss the behavior of the spectroscopic parameters of this state with respect to the density up to a high density corresponding to the core of neutron stars, rho approximate to 5 rho(sat). Both the mass and current coupling of this state show nonlinear behavior and decrease with respect to the density of the medium: the mass reaches roughly 30% of its vacuum value at rho = 5 rho(sat), while the current coupling approaches zero at rho approximate to 2.1 rho(sat), when the central values of the auxiliary and other input parameters are used.Öğe Scalar and vector self-energies of heavy baryons in nuclear medium(Elsevier Science Bv, 2017) Azizi, Kazem; Er, Nuray; Sundu, HayriyeThe in-medium sum rules are employed to calculate the shifts in the mass and residue as well as the scalar and vector self-energies of the heavy Lambda(Q), Sigma(Q) and Xi(Q) baryons, with Q being b or c quark. The maximum shift in mass due to nuclear matter belongs to the Sigma(c) baryon and it is found to be Delta m Sigma(c) = -936 MeV. In the case of residue, it is obtained that the residue of Sigma(b) baryon is maximally affected by the nuclear medium with the shift Delta lambda Sigma(b) = -0.014 GeV3. The scalar and vector self-energies are found to be Sigma(S)(Lambda b)= 653 MeV, Sigma(S)(Lambda b) = -614 MeV, Sigma(S)(Xi b) = -17 MeV, Sigma(S)(Lambda c)., = 272 MeV, Sigma(S)(Sigma c) = -936 MeV, Sigma(S)(Xi c) = -5 MeV and Sigma(nu)(Lambda c) = 436 +/- 148 MeV, Sigma(nu)(Sigma c) = 382 +/- 129 MeV, Sigma(nu)(Xi c) =15 +/- 5 MeV, Sigma(nu)(Lambda c) =151 +/- 45 MeV, Sigma(nu)(Sigma c)= 486 +/- 144 MeV and Sigma(nu)(Xi c) = 1.391 +/- 0.529 MeV. (C) 2017 The Author(s). Pcublished by Elsevier B.V.Öğe Scalar and vector self-energies of heavy baryons in nuclear medium (vol 960, pg 147, 2017)(Elsevier Science Bv, 2017) Azizi, Kazem; Er, Nuray; Sundu, HayriyeIn this erratum, we correct some misprints in equation (13) of our paper Nucl. Phys. A 960 (2017) 147–164. The corrected form of this equation is: As they are only misprints and their correct forms have been taken into account in numerical calculations, these corrections do not affect the numerical values of the parameters discussed in the paper.Öğe Semileptonic B -> (D)over-bar transition in a nuclear medium(American Physical Society, 2015) Azizi, Kazem; Er, Nuray; Sundu, HayriyeWe study the semileptonic tree-level B -> (D) over bar transition in the framework of QCD sum rules in a nuclear medium. In particular, we calculate the in-medium form factors entering the transition matrix elements defining this decay channel. It is found that the interactions of the participating particles with the medium lead to a considerable suppression in the branching ratio compared to the vacuum.Öğe X (3872): propagating in a dense medium(Elsevier Science Bv, 2018) Azizi, Kazem; Er, NurayIn cold nuclear matter, the shifts in the mass and current-meson coupling as well the vector self energy of the exotic X(3872) are calculated using the diquark-antidiquark current within the framework of the in-medium two-point QCD sum rule. At the rest frame of the medium, the three momentum of the considered particle is fixed to remove the contributions of the particles with negative energy. In the calculations, we include the in-medium condensates of quark-quark, gluon-gluon and quark-gluon. It is observed that, the shift due to the nuclear matter is negative and is about 25% when the saturation density is used. Such shift is considerably large and comparable with the nucleon' mass shift due to the nuclear medium. The negative shift in the current-meson coupling due to nuclear matter is approximately 10%. At the saturation density, the vector self energy of the exotic X(3872) state is found to be Sigma(nu) = 1.31 GeV. It is shown that the mass, current-meson coupling and vector self energy of X(3872) strongly depend on the density of cold nuclear matter. (C) 2018 The Author(s). Published by Elsevier B.V.
