The LHC possibilities to constrain the parameters of the Randall-Sundrum-like model with one warped extra dimension and small curvature through the diphoton production in the photon-induced process ...pp → pγγp → p′γγp′ are investigated. The acceptance of the forward detectors 0.015 < ξ < 0.15 , where ξ is the fractional proton momentum loss of the incident protons, is considered. The sensitivity bounds on the five-dimensional gravity scale are obtained as a function of the LHC integrated luminosity.
In this paper, potential of the LHC to explore the phenomenology of the Randall–Sundrum-like scenario with the small curvature for the process
p
p
→
p
γ
γ
p
→
p
μ
-
μ
+
p
through the subprocess
γ
γ
→
...μ
-
μ
+
is examined for two forward detector acceptances,
0.0015
<
ξ
<
0.5
and
0.1
<
ξ
<
0.5
. This process is known to be one of the most clean channels. The sensitivity bounds on the anomalous model parameters have been found at the
95
%
confidence level for various LHC integrated luminosity values.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We trace what happens with asymptotically free behavior of the running coupling in φ3 theory in six-dimensional spacetime, if to compactify two spatial dimensions on a 2D closed manifold. The result ...can be considered as an effective 4D theory of infinitely many KK-type scalar fields with triple interactions. The effective dimensional coupling constant inherits running to zero at high mass scales in a modified form depending on the size of the compact manifold. Some physical implications are discussed.
A
bstract
We have estimated the sensitivity to the anomalous couplings of the
γγγZ
vertex in the
γγ → γZ
scattering of the Compton backscattered photons at the CLIC. Both polarized and unpolarized ...collisions at the
e
+
e
−
energies 1500 GeV and 3000 GeV are addressed, and anomalous contributions to helicity amplitudes are derived. The differential and total cross sections are calculated. We have obtained 95% C.L. exclusion limits on the anomalous quartic gauge couplings (QGCs). They are compared with corresponding bounds derived for the
γγγZ
couplings via
γZ
production at the LHC. The constraints on the anomalous QGCs are one to two orders of magnitude more stringent that at the HL-LHC. The partial-wave unitarity constraints on the anomalous couplings are examined. It is shown that the unitarity is not violated in the region of the anomalous QGCs studied in the paper.
Abstract
We have examined the sensitivity of the axion-like particles (ALP) couplings to electroweak gauge bosons in the diphoton production at a future muon collider. The collisions at the
μ
+
μ
−
...energies of 3 TeV, 14 TeV, and 100 TeV are addressed. The differential cross sections versus the invariant mass of the final photons and total cross section versus minimal diphoton invariant mass are presented. We have derived the exclusion regions for the ALP-gauge boson coupling. The obtained bounds are much stronger than the current experimental bounds in the ALP mass region 10 GeV to 10 TeV. The partial-wave unitarity constraints on the ALP-gauge boson coupling are estimated. We have shown that the unitarity is not violated in the region of the ALP coupling studied in the present paper.
A
bstract
The virtual production of axion-like particles (ALPs) in the light-by-light scattering at the CLIC collider is studied. Both differential and total cross sections are calculated, assuming ...interaction of the ALP with photons via CP-odd term in the Lagrangian. The 95% C.L. exclusion regions for the ALP mass and its coupling constant are given. By comparing our results with existing collider bounds, we see that the ALP search at the CLIC has a great physics potential of searching for the ALPs, especially, in the mass region 1TeV-2.4 TeV, with the collision energy
s
= 3000 GeV and integrated luminosity
L
= 5000 fb
-1
for the Compton backscattered initial photons. In particular, our limits are stronger than recently obtained bounds for the ALP production in the light-by-light scattering at the LHC.
The search for downward-going and Earth-skimming ultrahigh energy cosmic neutrinos by the Surface Detector array of the Pierre Auger Observatory (PAO) is analyzed in a framework of the ...Arkani-Hamed–Dimopoulos–Dvali (ADD) model with n large extra dimensions under the assumption that the diffuse neutrino flux d N ν / d E ν has the form k E − 2 ν in the energy range 1 0 17 – 2.5 × 10 19 eV . The upper bound on the flux normalization k is obtained in the ADD model, taking into account that no neutrino events were found at the PAO. It is shown that for some values of n and ( n + 4 )-dimensional Planck scale M D our bound on k is more stringent than that of the Pierre Auger Collaboration. The lower bound on M D as a function of n is obtained.
Using Ramanujan’s Master Theorem, we derive two formulas for Hankel transforms of order zero for even functions using the inverse Mellin transform. The validity of these formulas require some special ...conditions on the functions. A number of illustrative examples are provided. One of them includes the evaluation of a new parametric integral involving the Bessel function
J
0
(
x
)
.
The anomalous quartic neutral couplings of the
γ
γ
γ
γ
vertex in a polarized light-by-light scattering of the Compton backscattered photons at the CLIC are examined. Both differential and total cross ...sections are calculated for
e
+
e
-
collision energies 1500 GeV and 3000 GeV. The helicity of the initial electron beams is taken to be
±
0.8
. The unpolarized and SM cross sections for the same values of helicities are also estimated. The 95% C.L. exclusion limits on two anomalous photon couplings
ζ
1
and
ζ
2
are calculated. The best bounds on these couplings are found to be
6.85
×
10
-
16
GeV
-
4
and
1.43
×
10
-
15
GeV
-
4
, respectively. The results are compared with the exclusion bounds obtained previously for the LHC and HL-LHC. It is shown that the light-by-light scattering at the CLIC, especially the polarized, has a greater potential to search for the anomalous quartic neutral couplings of the
γ
γ
γ
γ
vertex.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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