اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدNon-relativistic high-energy physics: top production and dark matter annihilation
89
0
0.0
(
0
)
تأليف
Martin Beneke
اسأل ChatGPT حول البحث
ﻻ يوجد ملخص باللغة العربية
Non-relativistic physics is often associated with atomic physics and low-energy phenomena of the strong interactions between nuclei and quarks. In this review we cover three topics in contemporary high-energy physics at or close to the TeV scale, where non-relativistic dynamics plays an important if not defining role. We first discuss in detail the third-order corrections to top-quark pair production in electron-positron collisions in the threshold region, which plays a major role at a future high-energy e+ e- collider. Threshold effects are also relevant in the production of heavy particles in hadronic collisions, where in addition to the Coulomb force soft gluon radiation contributes to enhanced quantum corrections. We review the joint resummation of non-relativistic and soft gluon effects for pair production of top quarks and supersymmetric particles to next-to-next-to-leading logarithmic accuracy. The third topic deals with pair annihilation of dark matter particles within the framework of the Minimal Supersymmetric Standard Model. Here the electroweak Yukawa force generated by the exchange of gauge and Higgs bosons can cause large Sommerfeld enhancements of the annihilation cross section in some parameter regions.
قيم البحث
اقرأ أيضاً
In this talk, we discuss the physics modelling of particle spectra arising from dark matter (DM) annihilation or decay. In the context of the indirect searches of DM, the final state products will, in general, undergo a set of complicated processes s
uch as resonance decays, QED/QCD radiation, hadronisation and hadron decays. This set of processes lead to stable particles (photons, positrons, anti-protons, and neutrinos among others) which travel for very long distances before reaching the detectors. The modelling of their spectra contains some uncertainties which are often neglected in the relevant analyses. We discuss the sources of these uncertainties and estimate their impact on photon energy spectra for benchmark DM scenarios with $m_chi in [10, 1000],$GeV. Instructions for how to retrieve complete tables from Zenodo are also provided.
When thermal rate equations are derived for the evolution of slow variables, it is often practical to parametrize the right-hand side with chemical potentials. To close the system, the chemical potentials are subsequently re-expressed in terms of the
slow variables, which involves the consideration of a susceptibility. Here we study a non-relativistic situation in which chemical potentials are large compared with the temperature, as is relevant for late-time pair annihilations in dark matter freeze-out. An order-of-magnitude estimate and a lattice simulation are presented for a susceptibility dominated by bound states of stop-like mediators. After this calibration, the formalism is applied to a model with Majorana singlet dark matter, confirming that masses up to the multi-TeV domain are viable in the presence of sufficient (though not beyond a limit) mass degeneracy in the dark sector.
DarkCapPy is a Python 3/Jupyter package for calculating rates associated with dark matter capture in the Earth, annihilation into light mediators, and the subsequent observable decay of the light mediators near the surface of the Earth. The package i
ncludes a calculation of the Sommerfeld enhancement at the center of the Earth and the timescale for capture--annihilation equilibrium. The code is open source and can be modified for other compact astronomical objects and mediator spins.
We compare dark matter production from the thermal bath in the early universe with its direct production through the decay of the inflaton. We show that even if dark matter does not possess a direct coupling with the inflaton, Standard Model loop pro
cesses may be sufficient to generate the correct relic abundance.
A summary is presented of the workshop top physics at linear colliders that was held at IFIC Valencia from the 30th of June to the 3rd July 2015. We present an up-to-date status report of studies into the potential for top quark physics of lepton col
liders with an energy reach that exceeds the top quark pair production threshold, with a focus on the linear collider projects ILC and CLIC. This summary shows that such projects can offer very competitive determinations of top quark properties (mass, width) and its interactions with other Standard Model particles, in particular electroweak gauge bosons and the Higgs boson. In both areas the prospects exceed the LHC potential significantly - often by an order of magnitude.
سجل دخول لتتمكن من نشر تعليقات
التعليقات
جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
