PKS 1424-418 | |
---|---|
Observation data (J2000.0 epoch) | |
Constellation | Centaurus |
Right ascension | 14h 27m 56.297s |
Declination | −42° 06′ 19.438″ |
Redshift | 1.522000 |
Heliocentric radial velocity | 456,824 km/s |
Distance | 9.439 Gly |
Apparent magnitude (V) | 17.7 |
Apparent magnitude (B) | 18.48 |
Characteristics | |
Type | Blazar; HPQ, FRSQ |
Other designations | |
LEDA 2827996, PMN J1427-4206, 4FGL J1427.9-4206, WMAP 191, G4Jy 1168 |
PKS 1424-418 is a blazar [1] located in the constellation of Centaurus. It has a redshift of 1.522 [2] [3] and was first discovered in 1971 by astronomer Keith Peter Tritton who identified the object as ultraviolet-excessive. [4] This object is also highly polarized with a compact radio source. [5] The radio spectrum of this source appears flat, making it a flat-spectrum radio quasar. [6]
PKS 1424-418 is found optically variable on the electromagnetic spectrum. [7] It is a strong source of gamma rays. [8] [9] Between 2008 and 2011, PKS 1424-418 showed four phases of bright flares at GeV energies. The flares have a high correlation between the energy ranges with the exception of one flare that occurred at the same time it showed low gamma activity. [10] In April 2013, it underwent a major gamma ray outburst with its peak flux reaching values of F(> 100 MeV) > 3 x 10−6 ph cm−2 s−1. According to Large Area Telescope observations, this emission originated beyond its broad-line region. [11] A near-infrared flare was witnessed in PKS 1424–418 in January 2018. [12] In August 2022, it once again displayed an episode of rapid flaring activity in both gamma ray and optical bands. [13]
PKS 1424-418 contains a radio structure, comprising a strong radio core and a weaker component with a position angle of 260°. [5] Further observations also showed the core has a size of 0.4 mas with extended emission at both the core's position and northwest. [14] In addition, the core has a flat spectral index of -0.04. [5] A jet is seen extending west from the core before becoming diffused. [15]
Between May 2009 and September 2019, the gamma ray emission from PKS 1424-418 was found to undergo a quasi-periodic oscillation with a 353-day flux oscillation period. [16] [17] A 355-day period with high significance level is also confirmed by adopting time domain methods. [18] This might be explained by orbital motion of a binary supermassive black hole system with the mass of a primary black hole being M ~ 3.5 x 108 - 5.5 x 109 Mʘ. [19]
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