The rare B(s) --> gammagamma decay has been investigated in the framework of the two-Higgs-doublet model. It is shown that the branching ratio has a great enhancement in comparison to the standard model (SM) prediction. We have found that the ratio of the square of the CP = 1 to CP = -1 amplitudes, \A+\2/\A-\2, which is always less than one in the SM, becomes greater than one for some values of M(H)/M(t). We have also calculated the direct CP-violating parameter epsilon'(gammagamma(-)). It is found that for K --> gammagamma decay its value is greater than the one which follows from the SM, while for B(s) --> gammagamma decay both models have the same predictions. Finally, we compare our results on B(s) --> gammagamma decay with the results of B(s) --> mu+mu- and B(s) --> mu+mu- decays which are of the same order of the coupling constant.


Inclusive and differential measurements of the t(t)over-bar charge asymmetry in pp collisions at root s=8 TeV
Khachatryan, V.; et. al. (Elsevier BV, 2016-06-01)
The t (t) over bar charge asymmetry is measured in proton-proton collisions at a centre-of-mass energy of 8 TeV. The data, collected with the CMS experiment at the LHC, correspond to an integrated luminosity of 19.7 fb(-1). Selected events contain an electron or a muon and four or more jets, where at least one jet is identified as originating from b-quark hadronization. The inclusive charge asymmetry is found to be 0.0010 +/- 0.0068 (stat)+/- 0.0037 (syst). In addition, differential charge asymmetries as a ...
Conference Report of Why R? Turkey 2021
Cavus, Mustafa; Aydin, Olgun; Evkaya, Ozan; Özdemir, Ozancan; Bezer, Deniz; Dar, Ugur (2021-06-01)
The Why R? Turkey 2021 as a three-day online conference was organized to bring together researchers and professionals from Turkey on April 16-17-18, 2021. We hereby aimed to promote the R community in Turkey by bringing R users with different backgrounds such as genetics, sociology, finance, economy, bio-statistics. There were 8 thematic sessions and 18 invited speakers. In this article, it is aimed to describe the preparation phase, technical details, and the impact of the conference on audience.
HAMDAN, NM; ZIQ, KA; HALLAK, AB; OZKAN, H (1993-09-01)
(Bi,Pb)2Sr2Ca2Cu3O10 high T(c) superconducting samples were subject to irradiation by 7 MeV Si ions. X-ray diffraction analysis showed that the intensity of the (00l) peaks decrease rapidly with ion irradiation, while that of the mixed index peaks (hkl) changes very little. The a-parameter decreases first then increases with ion fluence while the c-parameter increase continuously with ion irradiation.
Light mesons: pi, eta, and omega and exotic low mass meson production at intermediate energies in nucleon-nucleon scattering
Tatischeff, B; Yonnet, J; Rekalo, MP; Boivin, M; Comets, MP; Courtat, P; Gacougnolle, R; Le Bornec, Y; Loireleux, E; Reide, F; Willis, N (2000-11-01)
The reaction (p) over barp-->ppX was studied at three energies (T-p=1520, 1805, and 2100 MeV) and at several angles between 0 degrees and 17 degrees in the lab. The analyzing powers and differential cross sections of light meson production, X = pi, eta, and omega, were measured. The c.m. angular range varied between 0 degrees and 180 degrees where the incident energy combined with the experimental acceptance allow both forward and backward kinematical solutions. A theoretical analysis based on s-channel con...
Reaction of pentacarbonyl(eta(2)-bis(trimethylsilyl)ethyne)tungsten(0) with tricyclohexylphosphine: X-ray structure of pentacarbonyltricyclohexylphosphinetungsten(0)
Demircan, O; Özkar, Saim; Ulku, D; Yildirim, LT (2003-12-15)
The pentacarbonyl(?(2)-bis(trimethylsilyl)ethyne)tungsten(0), W(CO)(5)(?(2)-btmse), reacts with tricyclohexylphosphine, PCy3, to yield two stable endproducts which could be isolated and fully characterized by using the single crystal X-ray diffractometry and the MS, IR, and NMR spectroscopy: W(CO)(5)(PCy3) and trans-W(CO)(4)(PCy3)(2). The former complex is the alkyne substitution product, while the latter one is formed from the conversion of its labile cis-isomer, which is generated by further reaction of t...
Citation Formats
T. Alıyev, “BS-]GAMMA-GAMMA DECAY IN THE 2-HIGGS-DOUBLET MODEL,” PHYSICAL REVIEW D, pp. 1176–1184, 1993, Accessed: 00, 2020. [Online]. Available: