相关论文: Constraining DM through 21 cm observations

Cosmic reionization and dark matter decay can impact observations of the cosmic microwave sky in a similar way. A simultaneous study of both effects is required to constrain unstable dark matter from cosmic microwave background…

Dark matter (DM) could be a relic of freeze-in through a light mediator, where the DM is produced by extremely feeble, IR-dominated processes in the thermal Standard Model plasma. In the simplest viable models with the DM mass below the MeV…

We investigate constraints on scalar dark matter (DM) by analyzing the Lyman-alpha forest, which probes structure formation at medium and small scales, and also by studying its cosmological consequences at high and low redshift. For scalar…

We study the cosmological signatures of Invisibly Annihilating Dark Matter (IAnDM), where DM annihilates into dark radiation particles that are decoupled from the Standard Model (SM). In the simple benchmark model we consider here, such…

We study the absorption along lines of sight toward high-z radio sources caused by the 21 cm transition of neutral hydrogen in the intergalactic medium (IGM) before reionization. Using semi-analytic methods, we compute the number density of…

We study indirect detection signals from solar annihilation of dark matter (DM) particles into light right-handed (RH) neutrinos with a mass in a $1-5$ GeV range. These RH neutrinos can have a sufficiently long lifetime to allow them to…

The properties of the first galaxies, expected to drive the Cosmic Dawn (CD) and the Epoch of Reionization (EoR), are encoded in the 3D structure of the cosmic 21-cm signal. Parameter inference from upcoming 21-cm observations promises to…

Fuzzy dark matter (FDM) is a well motivated candidate for dark matter (DM) as its tiny mass and large de-Broglie wavelength suppress small-scale matter fluctuations, thereby solving some of the small-scale discrepancies in $\Lambda$CDM.…

We study the constraints on primordial magnetic fields (PMFs) in light of the global 21-cm signal observed during the dark ages. Primordial magnetic fields can heat the intergalactic medium (IGM) via magnetohydrodynamic effects. We…

Several interesting Dark Matter (DM) models invoke a dark sector leading to two types of relic particles, possibly interacting with each other: non-relativistic DM, and relativistic Dark Radiation (DR). These models have interesting…

We investigate a number of potential foregrounds for an ambitious goal of future radio telescopes such as the Square Kilometer Array (SKA) and Low Frequency Array (LOFAR): spatial tomography of neutral gas at high redshift in 21cm emission.…

From an assumed signal in a Dark Matter (DM) direct detection experiment a lower bound on the product of the DM--nucleon scattering cross section and the local DM density is derived, which is independent of the local DM velocity…

Leptophilic sub-MeV spin-1 dark matter (DM) can be converted into a photon via inelastic scattering with a free electron or absorption by a neutral hydrogen atom in the primordial plasma. We study for the first time the impact of the energy…

The recently claimed anomaly in the measurement of the 21 cm hydrogen absorption signal by EDGES at $z\sim 17$, if cosmological, requires the existence of new physics. The possible attempts to resolve the anomaly rely on either (i) cooling…

We present the first complete calculation of the history of the inhomogeneous 21-cm signal from neutral hydrogen during the era of the first stars. We use hybrid computational methods to capture the large-scale distribution of the first…

We investigate the effects of dark matter annihilation on objects with masses close to the sub-stellar limit, finding that the minimum mass for stable hydrogen burning is larger than the $\sim0.075 M_\odot $ value predicted in the Standard…

We examine cosmological, astrophysical and collider constraints on thermal dark matter (DM) with mass mX in the range 1 MeV to 10 GeV. Cosmic microwave background (CMB) observations, which severely constrain light symmetric DM, can be…

The first generation of redshifted 21 cm detection experiments, carried out with arrays like LOFAR, MWA and GMRT, will have a very low signal-to-noise ratio per resolution element (\sim 0.2). In addition, whereas the variance of the…

We re-examine the role of collisions in decoupling the HI 21-cm spin temperature from the cosmic microwave background (CMB). The cross section for de-exciting the 21-cm trasition in collisions with free electrons is more than 10 times…

From observations at low and high redshifts, it is well known that the bulk of dark matter (DM) has to be stable or at least very long-lived. However, the possibility that a small fraction of DM is unstable or that all DM decays with a…