相关论文: Zooming into the neutrino-associated blazar candid…
In the past years, evidence has started piling up that some high-energy cosmic neutrinos can be associated with blazars in flaring states. On February 26, 2022, a new blazar-neutrino coincidence has been reported: the track-like neutrino…
In recent years, changing-look blazars have called the traditional view of BL Lacs-flat spectrum radio quasars into question within the empirical classification of blazars. Based on the intensity of optical lines, they appear to transition…
The blazar PKS 0735+178 is possibly associated with multiple neutrino events observed by the IceCube, Baikal, Baksan, and KM3NeT neutrino telescopes while it was flaring in the $\gamma$-ray, X-ray, ultraviolet and optical bands. We present…
We report on multiwavelength target-of-opportunity observations of the blazar PKS 0735+178, located 2.2 degrees away from the best-fit position of the IceCube neutrino event 211208A. The source was in a high-flux state in the optical,…
We report on multiwavelength target-of-opportunity observations of the blazar PKS 0735+178, located 2.2$^\circ$ away from the best-fit position of the IceCube neutrino event IceCube-211208A detected on December 8, 2021. The source was in a…
We report on multiwavelength studies of a blazar NVSS J171822+423948, which is identified as the low-energy counterpart of 4FGL J1718.5+4237, the unique $\gamma$-ray source known to be cospatial with the IceCube neutrino event IC-201221A.…
Recent studies of individual track-like TeV-PeV IceCube neutrino events suggest that strongly jetted AGNs, blazars, can be plausible sources of extragalactic high-energy neutrinos. Although the broadband emission and neutrinos from such…
Context. Many questions on the nature of astrophysical counterparts of high-energy neutrinos remain unanswered. There is increasing evidence of a connection between blazar jets and neutrino events, with the flare of the gamma-ray blazar…
The blazars are one of the leading candidate sources of high-energy neutrinos. Recently, two blazars have been found to be temporally and spatially correlated with some IceCube high-energy neutrino events. The two blazars, GB6 J2113+1121…
In recent years, evidence has accumulated that some high-energy cosmic neutrinos can be associated with blazars. The strongest evidence for an individual association was found in the case of the blazar TXS 0506+056 in 2017. In July 2019,…
Blazars are active galactic nuclei (AGN) whose relativistic jets point nearly to the line of sight. Their compact radio structure can be imaged with very long baseline interferometry (VLBI) on parsec scales. Blazars at extremely high…
We present multifrequency Very Long Baseline Array (VLBA) observations of J16021+3326. These observations, along with variability data obtained from the Owens Valley Radio Observatory (OVRO) candidate gamma-ray blazar monitoring program,…
We show that the blazar PKS 1424+240, which has been recently associated by IceCube with a neutrino excess at the $3.3\,\sigma$ level together with three other sources, is similar to the first plausible non-stellar neutrino source, TXS…
Few high-redshift, radio-loud quasars are known to date. The extremely luminous, radio-bright quasar, SDSS J013127.34-032100.1 was recently discovered at a redshift of $z=5.18$. We observed the source with high resolution very long baseline…
We present a multi-wavelength study of a blazar PKS 0446+11, motivated by its spatial association with the neutrino event IC240105A detected by the IceCube Neutrino Observatory on 2024 January 5. The source is located 0.4 degrees from the…
Blazar jets are extreme environments, in which relativistic proton interactions with an ultraviolet photon field could give rise to photopion production. High-confidence associations of individual high-energy neutrinos with blazar flares…
Active galactic nuclei are the most luminous persistent (non-transient, even if often variable) objects in the Universe. They are bright in the entire electromagnetic spectrum. Blazars are a special class where the jets point nearly to our…
We report on a newly detected point-like source, HESS J1943+213 located in the Galactic plane. This source coincides with an unidentified hard X-ray source IGR J19443+2117, which was proposed to have radio and infrared counterparts. HESS…
We report our counterpart identification study for two high-energy neutrino events IC-130127A and IC-131204A listed in the IceCube Event Catalog of Alert Tracks. These two events belong to Gold alerts, which have a significant probability…
Blazars are promising sources of extragalactic high-energy astrophysical neutrinos, detected at energies $\gtrsim 10$ TeV by the IceCube neutrino observatory. Here, we report the first-ever broadband timing and spectral study of the…