https://doi.org/10.1140/epjc/s10052-020-7886-x
Regular Article - Theoretical Physics
Baryon-Dark matter interaction in presence of magnetic fields in light of EDGES signal
1
Theoretical Physics Division, Physical Research Laboratory, Ahmedabad, 380 009, India
2
Department of Physics, Indian Institute of Technology, Gandhinagar, Ahmedabad, 382 424, India
3
Department of Physics, National Institute of Technology, Shillong, Meghalaya, 793003, India
4
Department of physics and Astrophysics, University of Delhi, Delhi, 110 007, India
* e-mail: pravin@prl.res.in
Received:
20
October
2019
Accepted:
28
March
2020
Published online:
21
April
2020
We have shown that in presence of a cosmic magnetic field the bounds on baryon dark matter cross-section (
), dark-matter mass (
) and values of the magnetic field (
) can strongly influence each other. This requires to rework the bounds on 
, and which can explain the observed absorption signal by EDGES collaboration. The upper limit on the magnetic field strength can modify in presence of baryon-dark matter interaction cross-section. In the presence of a strong magnetic field, a large baryon-dark matter interaction cross-section is required to balance magnetic heating of gas to explain the EDGES signal as compared to a weak magnetic field. Subsequently, the strong magnetic-fields can even erase the 21 cm signal–this gives an upper bound on the strength of magnetic-fields, dark-matter mass and baryon-dark matter cross-section. In the special case when = 0, one can recover the bound on magnetic field strength calculated in [1]. In this work we find that the allowed range of the primordial magnetic field can increase by three orders of magnitude in comparison with [1]. We get upper bound on the magnetic field strength: 
G for the dark matter mass 
GeV.
© The Author(s), 2020
