News

In a significant advancement in the field of astrophysics, Dr Basabendu Barman, Assistant Professor in the Department of Physics, has published a groundbreaking paper titled “Dark matter-electron scattering and freeze-in scenarios in the light of \textit{Z’} mediation” in the prestigious Q1 journal, Physical Review D, known for its impact factor of 5.0 within the Nature Index.

Dr Barman’s research delves into the enigmatic realm of dark matter, proposing a novel mechanism through which dark matter might interact with the visible universe via a hypothesised fifth force. This interaction could provide vital insights into the nature of dark matter and its elusive characteristics. The study suggests that if this interaction is confirmed, experiments exploring the existence of a fifth force could concurrently unravel the mysteries surrounding dark matter, leading to a deeper understanding of the universe.

This publication not only highlights the potential for new discoveries in particle physics but also positions SRM University-AP at the forefront of cutting-edge research in dark matter studies. Dr. Barman’s findings could pave the way for further exploration and experimental validation, ultimately contributing to the ongoing quest to decode one of the universe’s greatest mysteries.

Abstract:

We investigate dark matter (DM-)electron scattering in a minimal U〖(1)〗_X extension of the Standard Model (SM), where the DM can appear as a Majorana fermion, a complex singlet scalar, or a Dirac fermion. To study bounds on the new gauge coupling and new gauge boson mass, from DM-electron scattering, we consider several direct search experiments like CDMS, DAMIC, SENSEI, PandaX-II, DarkSide-50, and XENON1T-S2 for different U〖(1)〗_X charges. In this setup, we consider DM production via freeze-in in both radiation-dominated and modified cosmological backgrounds to project sensitivities onto coupling vs mass plane satisfying observed relic abundance. DM-electron scattering could provide comparable, or even stronger, bounds compared to those obtained from the electron/muon (g-2), low-energy scattering, and intensity frontier experiments within mass range of 0.01-0.1 GeV. Constrains from freeze-in could provide stronger sensitivities for new gauge boson masses above about 1 GeV ; however, these limits are comparable to those obtained from LHCb and LEP experiments for mass between 10-150 GeV. In the future, electron-muon scattering (MUonE), proton (FASER and DUNE), and electron/positron (ILC) beam-dump experiments could probe these parameters.

From Layperson’s perspective:

We know there are four fundamental forces in nature: strong, weak, electromagnetic, and gravitational. But what if there’s a hidden, fifth force we haven’t discovered yet? The Standard Model of particle physics, which organizes all known particles, doesn’t include this fifth force (and doesn’t include gravity either, unfortunately). So, how can we theoretically create a particle physics model for this possible fifth force? That’s what we explore in this paper. Interestingly, there are already experiments (for example, the Large Hadron Collider or LHC at CERN, Geneva) searching for signs of fifth forces. If this force exists, our model could be tested by these experiments. But there’s more! We also wanted to tackle a big mystery in cosmology: dark matter. Dark matter makes up about 24% of the universe, but we’ve never directly detected it because it doesn’t reflect light—it’s “dark.” However, there are smart ways to try to find it. In this paper, we propose how the same dark matter might interact with the visible universe through this fifth force and thereby leave their footprints. If true, therefore, the experiments looking for the fifth force could also give us clues about the nature of dark matter.

Title:

Dark matter-electron scattering and freeze-in scenarios in the light of Z’ mediation.

In BibTeX (citation) format:

@article{PhysRevD.110.055029,
title = {Dark matter-electron scattering and freeze-in scenarios in the light of ${Z}^{\ensuremath{‘}}$ mediation},
author = {Barman, Basabendu and Das, Arindam and Mandal, Sanjoy},
journal = {Phys. Rev. D},
volume = {110},
issue = {5},
pages = {055029},
numpages = {20},
year = {2024},
month = {Sep},
publisher = {American Physical Society},
doi = {10.1103/PhysRevD.110.055029},
url = {https://link.aps.org/doi/10.1103/PhysRevD.110.055029}
}

Practical Implementations & Social Impact:

The primary goal of this study is to explore what lies beyond the known, visible universe. This curiosity has driven humanity for centuries—to build rockets and explore outer space and to smash particles in colliders, searching for the mysteries hidden within the atom. The desire to uncover the unknown, to shed light on the darkness, is a fundamental part of what it means to be human. In this sense, the work contributes to the realm of pure intellectual pursuit. Science speaks the language of data, and data is born from experiments. The validation of any well-constructed theory ultimately depends on experimental evidence. For this reason, it is essential for society to cultivate a culture that values fundamental scientific discussion and increases funding for basic research.

Collaborations:

This work was done in collaboration with Prof. Arindam Das from the Department of Physics, Hokkaido University, Sapporo, Japan, and Dr. Sanjoy Mandal from the Korea Institute for Advanced Study (KIAS), Seoul, Korea.

Future plans:

1. A closer look into early universe dynamics by performing more involved simulations.
2. Connection between particle physics models and early Universe cosmology.
3. Complementary searches from different experiments in unravelling new physics beyond the Standard Model.
4. Searching new physics at energy and intensity frontier.

Link to the Paper