Pulsar timing residual induced by ultralight tensor dark matter

Abstract

Ultralight boson fields, with a mass around 10-23 eV, are promising candidates for the elusive cosmological dark matter. These fields induce a periodic oscillation of the spacetime metric in the nanohertz frequency band, which is detectable by pulsar timing arrays. In this paper, we investigate the gravitational effect of ultralight tensor dark matter on the arrival time of radio pulses from pulsars. We find that the pulsar timing signal caused by tensor dark matter exhibits a different angular dependence than that by scalar and vector dark matter, making it possible to distinguish the ultralight dark matter signal with different spins. Combining the gravitational effect and the coupling effect of ultralight tensor dark matter with standard model matter provides a complementary way to constrain the coupling parameter α. We estimate α ≲ 10-6 ∼ 10-5 in the mass range m < 5 × 10-23 eV with current pulsar timing array.

Probing the equation of state of the early Universe with pulsar timing arrays

“…Recently, four major pulsar timing array (PTA) collaborations, namely the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) [1,2], the Parkes PTA (PPTA) [3,4], the European PTA (EPTA) along with the Indian PTA (InPTA) [5,6], and the Chinese PTA (CPTA) [7], have jointly announced compelling evidence of a commonspectrum signal consistent with the Hellings-Downs spatial correlations [8] in their latest data sets, thus suggesting a gravitational wave (GW) origin for this signal. While various physical phenomena [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] can produce GW signals within the PTA frequency band, the precise origin of this signal, whether attributed to supermassive black hole binaries [24][25][26][27] or other cosmological sources , remains an ongoing subject of investigation.…”

Constraints on the primordial curvature power spectrum by pulsar timing array data: a polynomial parameterization approach

“…This paper focuses on exploring the observed PTA signal explained by SIGWs. For further physical processes contributing to the pulsar timing array (PTA) band, please refer to [56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71].…”

Model-independent reconstruction of the primordial curvature power spectrum from PTA data

“…Among the various hypotheses, a particularly promising candidate is the scalar-induced gravitational waves (SIGWs); and this paper focuses on investigating the scenario where the observed signal arises from SIGWs. For other physical processes contributing to the PTA band, please see [30][31][32][33][34][35][36][37][38][39][40][41][42][43].…”