相关论文: Dibaryons cannot be the dark matter
Quasar absorption lines now permit a direct probe of deuterium abundances in primordial material, with the best current estimate $ (D/H)=1.9\pm 0.4 \times 10^{-4}$. If this is the universal primordial abundance $(D/H)_p$, Standard Big Bang…
We calculate saturation curves for strange hadron matter using recently constructed baryon-baryon potentials which are constrained by SU(3) symmetry. All possible interaction channels within the baryon octet (consisting of $N$, $\Lambda$,…
It has been recently suggested that stable, supersymmetric B-balls formed in the early universe could not only be the dark matter at the present epoch, but also be responsible for baryogenesis by their partial evaporation at high…
The hadron spectrum of SU(2) lattice gauge theory with two flavours of Wilson quark is studied on an 8^3x16 lattice using all-to-all propagators, with particular emphasis on the dependence on quark chemical potential mu. As mu is increased…
The origin and composition of the cosmological dark matter remain a mystery. However, upcoming 21-cm measurements during cosmic dawn, the period of the first stellar formation, can provide new clues on the nature of dark matter. During this…
The dark matter of the Abell 1689 galaxy cluster is modeled by thermal, non-relativistic gravitating fermions and its galaxies and X-ray gas by isothermal distributions. A fit yields a mass of $h_{70}^{1/2}(12/{\overline g})^{1/4}$1.445…
We consider the production of axion dark matter through the misalignment mechanism in the context of a nonstandard cosmological history involving early matter domination by a scalar field with a time-dependent decay rate. In cases where the…
Assuming that (1) the universe underwent a post-inflationary accelerated expansion phase driven by a fluid with equation of state $P=w\rho$ and $-1<w<-1/3$, that (2) the cosmic horizon in an accelerating, quasi-de Sitter universe has a…
In the present universe visible and dark matter contribute comparable energy density although they have different properties. This coincidence can be elegantly explained if the dark matter relic density, originating from a dark matter…
We present our final results for the mass of the six quark flavor singlet state (J^P=0^+, S=-2) called H dibaryon, which would be the lightest possible strangelet in the context of strange quark matter. The calculations are performed in…
There appear to be three challenges that any theory of dark matter must face: (i) why is $\Omega_{DM}$ of the same order as $\Omega_{Baryons}$ ? (ii) what are the near solar mass objects ($\sim 0.5 M_{\odot}$) observed by the MACHO…
Pseudo-Dirac Dark Matter is a viable type of dark matter which originates from a new Dirac fermion whose two Weyl states get slightly split in mass by a small Majorana term. The decay of the heavier to the lighter state naturally occurs…
We consider a simple class of models in which the relic density of dark matter is determined by the baryon asymmetry of the universe. In these models a $B - L$ asymmetry generated at high temperatures is transfered to the dark matter, which…
In the early Universe, strongly interacting matter was a quark-gluon plasma. Both lattice computations and heavy ion collision experiments however tell us that, in the absence of chemical potentials, no plasma survives at $T <\sim 150$ MeV.…
We study a novel dark matter production mechanism based on the freeze-in through semi-production, i.e. the inverse semi-annihilation processes. A peculiar feature of this scenario is that the production rate is suppressed by a small initial…
In this letter in the framework of a simple see-saw scenario with two (or three) quasi degenerate Majorana neutrinos we propose that one of these neutrinos can be very weakly coupled, yet there is a mechanism of the generation of the…
If dark matter (DM) contains equal numbers of u,d,s quarks, the ratio of DM and ordinary matter densities is shown to follow from the Boltzmann distribution in the Quark Gluon Plasma. For sexaquark DM in the 1860-1880 MeV mass range…
We propose a simple scenario in which dark matter (DM) emerges as a stable neutral hadronic thermal relics, its stability following from an exact $\operatorname{U}(1)_D$ symmetry. Neutrinos pick up radiatively induced Majorana masses from…
We provide a simple UV theory for a Dirac dark matter with a massless Abelian gauge boson. We introduce a single fermion transforming as the $\bf{16}$ representation in the SO(10)$'$ gauge group, which is assumed to be spontaneously broken…
We present an explicit model where the decay of an R-parity even scalar $S$ with ${\cal O}({\rm TeV})$ mass is the origin of non-thermal dark matter. The correct relic abundance can be produced for both large and small annihilation rates in…