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, Volume: 10( 8) DOI: 10.37532/2320-6756.2022.10(8).293

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Look for Gamma-Ray Emission from Tidal Disruption Events that may be Related to Ice Cube Neutrinos in Accretion Flares

*Correspondence:

Sophie Relish Research Executive, University of Physics, UK
E-mail: physastronomy@journalres.com

Abstract

High-energy neutrinos may originate from outflows or disk-coronas created in tidal disruption events (TDEs) of supermassive black holes. According to multi-messenger follow-ups, three TDEs (AT2019 dsg, AT2019 fdr, and AT2019 aalc) are connected to high-energy astrophysical neutrinos. For the three sources, no GeV photons are present with the neutrino. In this study, we looked for high-energy gamma-ray emissions from a bigger sample of TDE candidates that had been seen by the Zwicky Transient Facility (ZTF). The highest limits of the gamma-ray emission flow are reported, and no substantial GeV emission was seen. The aggregate gamma-ray emission of this class of sources was not strong enough to be observed by the Fermi Large Area Telescope, therefore we did a stacking analysis for the sample sources (Fermi-LAT). The high-energy gamma-ray emission from the sample TDEs may not have been detected because the source absorbs the gamma rays with soft photons. The top limit on the emission radius of the neutrino generation for these TDEs is determined using a model-based hypothesis: For average TDE parameter values, R 1016 cm.

Keywords

Black holes; Photons; Cosmos

Introduction

TeV-PeV neutrinos have been discovered by the Ice Cube observatory for the first time, providing a rare opportunity to study the high-energy cosmos. The nature of the incontestable sources is unknown despite numerous cross-correlation analyses between the Ice Cube point-source data and multi-wavelength catalogs, as well as quick follow-up observations utilizing the real-time alert framework. This is true even though it is known that many of the neutrinos are of astrophysical origin, as indicated by the isotropic distribution of a highly potent high-energy BL Lac object at a redshift of z=0.3365, after the Ice Cube-170922A neutrino event for the first time. Due to the poor angular resolution of order 1 degree–10 degrees at observed energies for Ice Cube neutrinos, although these candidates exhibit multi-wavelength emission in positional and temporal coincidence with high-energy neutrino events, the obtained significance level is not high enough to claim a firm identification. These connections and other theoretical justifications imply that a variety of astrophysical populations may combine to produce the neutrino flux. Star-Forming Galaxies (SFGs), Gamma-Ray Bursts (GRBs), and Active Galactic Nuclei (AGN; blazars or cores) are some of the potential astrophysical sources that could produce high-energy neutrinos. As previously indicated, TDEs have drawn increasing attention recently. When a star approaches a black hole too closely, unusual transients called TDEs occur. TDEs may be the origin of Ultra-High-Energy Cosmic Rays (UHECRs), according to studies. In particular, for the subgroup of TDEs containing high-energy neutrinos and Relativistic jets that were successful or choked. Three TDE candidates were recently identified. ZTF have been identified as the high-energy astrophysical neutrino's counterparts.in follow-up campaigns using several messengers. In terms of observation, the three noticed Over a wide range of wavelengths, neutrino-emitting TDEs exhibit similar properties, using an Optical-Ultraviolet (OUV) band brilliant black body spectrum, infrared as well as radio radiation from the (IR) echo High-energy non-thermal electron synchrotron spectrum. Numerous hypotheses, including TDE jets, outflow-cloud interactions, the core area of AGNs, or accretion flares from large black holes, have been put forth to comprehend these events. The neutrinos are generated in these models by p interactions between relativistic protons that have been accelerated in the jet, accretion flows, coronal or disk-driven winds, and the powerful OUV/X-ray radiation of the TDE. Alternatively, by interacting with clouds via the pp process, protons accelerated by the outflow's bow shocks produce PeV neutrinos. The Fermi-LAT does not detect any gamma-ray emission from the three TDEs, which can be attributed to their absorption by the OUV and/or X-ray radiation field via annihilation. The physical mechanisms at work in TDEs are not entirely known; for instance, the radius at which different mechanisms operate is rather imprecise. In TDEs, X-ray photons are frequently seen. Soft photons, or the annihilation opacity between a high-energy photon (Eh) and a low-energy photon (Et) at the source, will absorb GeV gamma-ray emission produced directly in 0 decay or through the associated cascade process.

Conclusion

The energy of low-energy tar for a high-energy photon commonly observed by the Fermi-LAT photons' (Et) formula is Et, which is simply delivered by the recorded thermal soft X-ray emission. Optical depth is determined by where the cross section for absorption is roughly approximated by (T is the Thompson cross section), where n is the density of the interacting target photons. R is the emission radius and there are high-energy photons. The just provided eV based on the observable thermal soft X-ray emission. optical depth is calculated where nearly approximates the cross section for absorption. The density of the interacting target photons, n, is represented by the Thompson cross-section. There are high-energy photons and the emission radius is R. An X-ray detection picture was a very gentle thermal spectrum, culminating at about, consequently the density of Soft photons n can be displaced. The radiation's energy density is UX.