Related papers: Reviving Millicharged Dark Matter for 21-cm Cosmol…
We investigate the hypothesis that Coulomb-type interactions between dark matter (DM) and baryons explain the anomalously low 21cm brightness-temperature minimum at redshift z ~ 17 that was recently measured by the EDGES experiment. In…
Heat transfer between baryons and millicharged dark matter has been invoked as a possible explanation for the anomalous 21-cm absorption signal seen by EDGES. Prior work has shown that the solution requires that millicharged particles make…
We present and compare several cosmological constraints on the cross section for elastic scattering between dark matter (DM) and baryons, for cross sections with a range of power-law dependences on the DM-baryon relative velocity $v$,…
Dark matter interactions with massless or very light Standard Model particles, as photons or neutrinos, may lead to a suppression of the matter power spectrum at small scales and of the number of low mass haloes. Bounds on the dark matter…
Dark matter which scatters off ordinary matter with a relatively large cross section cannot be constrained by deep underground WIMP experiments, due to the energy loss of DM along its path. However, for a sufficiently large cross section,…
The EDGES collaboration has recently reported the detection of an unexpectedly stronger absorption signal in the global 21-cm spectrum around cosmic red-shift z = 17, resulting in the significant cooling of the primordial gas. The cooling…
Dark matter-baryon interactions can cool the baryonic fluid, which has been shown to modify the cosmological 21-cm global signal. We show that in a two-component dark sector with an interacting millicharged component, dark matter-baryon…
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…
For dark matter (DM) particles with masses in the 0.6 - 6 m_p range, we set stringent constraints on the interaction cross-sections for scattering with ordinary baryonic matter. These constraints follow from the recognition that such…
The recent detection of an anomalously strong 21-cm signal of neutral hydrogen from Cosmic Dawn by the EDGES Low-Band radio experiment can be explained if cold dark matter particles scattered off the baryons draining excess energy from the…
We present a novel approach to detect millicharged dark matter (mDM) by using a high-sensitivity magnetometer coupled with the resonant and broadband readout circuits. In the external magnetic field, the interaction between mDM and the…
The EDGES Collaboration has recently announced the detection of the 21-cm spectrum with an absorption profile centred at $78$ megahertz, of which the depth is deeper than that expected by the standard cosmological paradigm. To enrich the…
Analysis of EDGES data shows an absorption signal of the redshifted 21-cm line of atomic hydrogen at $z\sim 17$ which is stronger than expected from the standard $\Lambda$CDM model. The absorption signal interpreted as brightness…
A strong absorption profile was reported by the EDGES Collaboration, which indicates the hydrogen gas being colder than expected. It could be signatures of non-gravitational interactions between normal matter and dark matter (DM), and a…
The stronger than expected 21-cm absorption was observed by EDGES recently, and another anomaly of $^8$Be transitions would be signatures of new interactions. These two issues may be related to each other, e.g., pseudoscalar $A$ mediated…
The CMB observation sets stringent constraints on MeV dark matter (DM) annihilating into charged states/photons in s-wave, and the recent observation of the 21-cm absorption at the cosmic dawn reported by EDGES is also very strict for…
The observational value of the velocity dispersion, $\Delta\upsilon$, is missing in the Dark Matter (DM) puzzle. Non-zero or non-thermal DM velocities can drastically influence Large Scale Structure and the 21-cm temperature at the epoch of…
It has recently been proposed that the relatively inert, highly symmetric, neutral flavor singlet scalar hadron made of uuddss quarks may have a mass < 2 (m_p + m_e). This is consistent with QCD theory, and with existing accelerator and…
Millicharged particles are well-motivated dark matter candidates arising in many extensions of the Standard Model. We show that, despite their tiny coupling $e_m$ to photons, millicharged dark matter (mDM) in the Earth's geomagnetic field…
Asymmetric Dark Matter (ADM) models relate the dark matter density to the baryon asymmetry, so that a natural mass scale for ADM is around a few GeV. In existing models of ADM, this mass scale is unexplained; here we generate this GeV scale…