The effects of QCD equation of state on the relic density of WIMP dark matter M Drees, F Hajkarim, ER Schmitz Journal of Cosmology and Astroparticle Physics 2015 (06), 025, 2015 | 142 | 2015 |

Primordial gravitational waves in nonstandard cosmologies N Bernal, F Hajkarim Physical Review D 100 (6), 063502, 2019 | 69 | 2019 |

Dark matter production in an early matter dominated era M Drees, F Hajkarim Journal of Cosmology and Astroparticle Physics 2018 (02), 057, 2018 | 69 | 2018 |

Thermal history of the early Universe and primordial gravitational waves from induced scalar perturbations F Hajkarim, J Schaffner-Bielich Physical Review D 101 (4), 043522, 2020 | 60 | 2020 |

Neutralino dark matter in scenarios with early matter domination M Drees, F Hajkarim Journal of High Energy Physics 2018 (12), 1-28, 2018 | 46 | 2018 |

Thermal axion production at low temperatures: a smooth treatment of the QCD phase transition F D’Eramo, F Hajkarim, S Yun Physical Review Letters 128 (15), 152001, 2022 | 43 | 2022 |

Thermal QCD Axions across Thresholds F D’Eramo, F Hajkarim, S Yun Journal of High Energy Physics 2021 (10), 1-60, 2021 | 42 | 2021 |

Cosmological bound on the QCD axion mass, redux F D'Eramo, E Di Valentino, W Giare, F Hajkarim, A Melchiorri, O Mena, ... Journal of Cosmology and Astroparticle Physics 2022 (09), 022, 2022 | 40 | 2022 |

Pion condensation in the early universe at nonvanishing lepton flavor asymmetry and its gravitational wave signatures V Vovchenko, BB Brandt, F Cuteri, G Endrődi, F Hajkarim, ... Physical Review Letters 126 (1), 012701, 2021 | 37 | 2021 |

Primordial gravitational wave signals in modified cosmologies N Bernal, A Ghoshal, F Hajkarim, G Lambiase Journal of Cosmology and Astroparticle Physics 2020 (11), 051, 2020 | 37 | 2020 |

Axion dark matter in the time of primordial black holes N Bernal, F Hajkarim, Y Xu Physical Review D 104 (7), 075007, 2021 | 32 | 2021 |

Shedding new light on sterile neutrinos from XENON1T experiment S Shakeri, F Hajkarim, SS Xue Journal of High Energy Physics 2020 (12), 1-33, 2020 | 26 | 2020 |

Stability of Einstein static universe over Lyra geometry F Darabi, Y Heydarzade, F Hajkarim Canadian Journal of Physics 93 (12), 1566-1570, 2015 | 26 | 2015 |

Did we hear the sound of the Universe boiling? Analysis using the full fluid velocity profiles and NANOGrav 15-year data T Ghosh, A Ghoshal, HK Guo, F Hajkarim, SF King, K Sinha, X Wang, ... arXiv preprint arXiv:2307.02259, 2023 | 24* | 2023 |

Effects of the QCD equation of state and lepton asymmetry on primordial gravitational waves S Wystub, MM Wygas, F Hajkarim, J Schaffner-Bielich Physical Review D 99 (arXiv: 1904.01046), 2019 | 19* | 2019 |

On the viability of Planck scale cosmology with quartessence M Khodadi, K Nozari, F Hajkarim The European Physical Journal C 78, 1-12, 2018 | 15 | 2018 |

Probing axions via light circular polarization and event horizon telescope S Shakeri, F Hajkarim Journal of Cosmology and Astroparticle Physics 2023 (04), 017, 2023 | 8 | 2023 |

Lepton and *W*-boson mass anomalies in the DFSZ axion modelM Ahmadvand, F Hajkarim The European Physical Journal C 83 (11), 1021, 2023 | 1 | 2023 |

Dark radiation from the primordial thermal bath in momentum space F D'Eramo, F Hajkarim, A Lenoci Journal of Cosmology and Astroparticle Physics 2024 (03), 009, 2024 | | 2024 |

New Constraints on Axion-Like Particles from IXPE Polarization Data for Magnetars E Gau, F Hajkarim, SP Harris, PS Dev, JF Fortin, H Krawczynski, K Sinha arXiv preprint arXiv:2312.14153, 2023 | | 2023 |