skip to main content

Title: High-energy neutrino emission from magnetized jets of rapidly rotating protomagnetars

Relativistic jets originating from protomagnetar central engines can lead to long duration gamma-ray bursts (GRBs) and are considered potential sources of ultra-high-energy cosmic rays and secondary neutrinos. We explore the propagation of such jets through a broad range of progenitors, from stars which have shed their envelopes to supergiants which have not. We use a semi-analytical spin-down model for the strongly magnetized and rapidly rotating protoneutron star (PNS) to investigate the role of central engine properties such as the surface dipole field strength, initial rotation period, and jet opening angle on the interactions and dynamical evolution of the jet-cocoon system. With this model, we determine the properties of the relativistic jet, the mildly relativistic cocoon, and the collimation shock in terms of system parameters such as the time-dependent jet luminosity, injection angle, and density profile of the stellar medium. We also analyse the criteria for a successful jet breakout, the maximum energy that can be deposited into the cocoon by the relativistic jet, and structural stability of the magnetized outflow relative to local instabilities. Lastly, we compute the high-energy neutrino emission as these magnetized outflows burrow through their progenitors. Precursor neutrinos from successful GRB jets are unlikely to be detected by IceCube, which is consistent with the results of previous works. On the other hand, we find that high-energy neutrinos may be produced for extended progenitors like blue and red supergiants, and we estimate the detectability of neutrinos with next generation detectors such as IceCube-Gen2.

more » « less
Award ID(s):
2209420 1914409 1908960 2108467 2108466 1908689
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Medium: X Size: p. 2391-2407
["p. 2391-2407"]
Sponsoring Org:
National Science Foundation
More Like this
  1. ABSTRACT Without additional heating, radiative cooling of the halo gas of massive galaxies (Milky Way-mass and above) produces cold gas or stars exceeding that observed. Heating from active galactic nucleus (AGN) jets is likely required, but the jet properties remain unclear. This is particularly challenging for galaxy simulations, where the resolution is orders-of-magnitude insufficient to resolve jet formation and evolution. On such scales, the uncertain parameters include the jet energy form [kinetic, thermal, cosmic ray (CR)]; energy, momentum, and mass flux; magnetic fields; opening angle; precession; and duty cycle. We investigate these parameters in a $10^{14}\, {\rm M}_{\odot }$ halo using high-resolution non-cosmological magnetohydrodynamic simulations with the FIRE-2 (Feedback In Realistic Environments) stellar feedback model, conduction, and viscosity. We explore which scenarios qualitatively meet observational constraints on the halo gas and show that CR-dominated jets most efficiently quench the galaxy by providing CR pressure support and modifying the thermal instability. Mildly relativistic (∼MeV or ∼1010K) thermal plasma jets work but require ∼10 times larger energy input. For fixed energy flux, jets with higher specific energy (longer cooling times) quench more effectively. For this halo mass, kinetic jets are inefficient at quenching unless they have wide opening or precession angles. Magnetic fields also matter less except when the magnetic energy flux reaches ≳ 1044 erg s−1 in a kinetic jet model, which significantly widens the jet cocoon. The criteria for a successful jet model are an optimal energy flux and a sufficiently wide jet cocoon with a long enough cooling time at the cooling radius. 
    more » « less
  2. Abstract

    We present a bottom-up calculation of the flux of ultrahigh-energy cosmic rays (UHECRs) and high-energy neutrinos produced by powerful jets of active galactic nuclei (AGNs). By propagating test particles in 3D relativistic magnetohydrodynamic jet simulations, including a Monte Carlo treatment of sub-grid pitch-angle scattering and attenuation losses due to realistic photon fields, we study the spectrum and composition of the accelerated UHECRs and estimate the amount of neutrinos produced in such sources. We find that UHECRs may not be significantly affected by photodisintegration in AGN jets where theespressomechanism efficiently accelerates particles, consistent with Auger’s results that favor a heavy composition at the highest energies. Moreover, we present estimates andupper boundsfor the flux of high-energy neutrinos expected from AGN jets. In particular, we find that (i) source neutrinos may account for a sizable fraction, or even dominate, the expected flux of cosmogenic neutrinos; (ii) neutrinos from theβ-decay of secondary neutrons produced in nucleus photodisintegration end up in the teraelectronvolt to petaelectronvolt band observed by IceCube, but can hardly account for the observed flux; (iii) UHECRs accelerated via theespressomechanism lead to nearly isotropic neutrino emission, which suggests that nearby radio galaxies may be more promising as potential sources. We discuss our results in light of multimessenger astronomy and current/future neutrino experiments.

    more » « less
  3. Abstract We investigate prospects for the detection of high-energy neutrinos produced in the prolonged jets of short gamma-ray bursts (sGRBs). The X-ray light curves of sGRBs show extended emission components lasting for 100–1000 s, which are considered to be produced by prolonged engine activity. Jets produced by such activity should interact with photons in the cocoon formed by the propagation of the jet inside the ejecta of neutron star mergers. We calculate neutrino emission from jets produced by prolonged engine activity, taking account of the interaction between photons provided from the cocoon and cosmic rays accelerated in the jets. We find that IceCube-Gen2, a future neutrino telescope, with second-generation gravitational-wave detectors will probably be able to observe neutrino signals associated with gravitational waves with around 10 years of operation, regardless of the assumed value of the Lorentz factor of the jets. Neutrino observations may enable us to constrain the dissipation region of the jets. We apply this model to GRB 211211A, a peculiar long GRB whose origin may be a binary neutron star merger. Our model predicts that IceCube is unlikely to detect any associated neutrinos, but a few similar events will be able to put a meaningful constraint on the physical quantities of the prolonged engine activities. 
    more » « less

    Evidence is mounting that recent multiwavelength detections of fast blue optical transients (FBOTs) in star-forming galaxies comprise a new class of transients, whose origin is yet to be understood. We show that hydrogen-rich collapsing stars that launch relativistic jets near the central engine can naturally explain the entire set of FBOT observables. The jet–star interaction forms a mildly relativistic shocked jet (inner cocoon) component, which powers cooling emission that dominates the high velocity optical signal during the first few weeks, with a typical energy of ∼1050–1051 erg. During this time, the cocoon radial energy distribution implies that the optical light curve exhibits a fast decay of $L \,\, \buildrel\propto \over \sim \,\,t^{-2.4}$. After a few weeks, when the velocity of the emitting shell is ∼0.01 c, the cocoon becomes transparent, and the cooling envelope governs the emission. The interaction between the cocoon and the dense circumstellar winds generates synchrotron self-absorbed emission in the radio bands, featuring a steady rise on a month time-scale. After a few months the relativistic outflow decelerates, enters the observer’s line of sight, and powers the peak of the radio light curve, which rapidly decays thereafter. The jet (and the inner cocoon) becomes optically thin to X-rays ∼day after the collapse, allowing X-ray photons to diffuse from the central engine that launched the jet to the observer. Cocoon cooling emission is expected at higher volumetric rates than gamma-ray bursts (GRBs) by a factor of a few, similar to FBOTs. We rule out uncollimated outflows, however, both GRB jets and failed collimated jets are compatible with all observables.

    more » « less

    GW170817/GRB170817A has offered unprecedented insight into binary neutron star post-merger systems. Its Prompt and afterglow emission imply the presence of a tightly collimated relativistic jet with a smooth transverse structure. However, it remains unclear whether and how the central engine can produce such structured jets. Here, we utilize 3D general relativistic magnetohydrodynamic simulations starting with a black hole surrounded by a magnetized torus with properties typically expected of a post-merger system. We follow the jet, as it is self-consistently launched, from the scale of the compact object out to more than three orders of magnitude in distance. We find that this naturally results in a structured jet, which is collimated by the disc wind into a half-opening angle of roughly 10°; its emission can explain features of both the prompt and afterglow emission of GRB170817A for a 30° observing angle. Our work is the first to compute the afterglow, in the context of a binary merger, from a relativistic magnetized jet self-consistently generated by an accreting black hole, with the jet’s transverse structure determined by the accretion physics and not prescribed at any point.

    more » « less