PKS 2338+000 is one of the
largest galaxies. With a
diameter spanning 667,000 light-years across, the galaxy is visually
luminous[4] with a radio-loud nucleus scintillating than 5mJy at 1.4 GHz.[5] It is a
Seyfert 2 galaxy with
narrow-lines that has a measurement of ~ 102 km s−1.[6][7] PKS 2338+000 is a
blazar,[8][9] an active galaxy type. Such blazars show powerful emission across its
electromagnetic spectrum. It is found to the strongest
active galactic nucleus (AGN) in its core.[10] The
radio jet of PKS 2338+000 is accurate is below 10°parsec-scale .[11] The
radio source in PKS 2338+000 on the other hand, is measured 150
GHz of 3 mJy ≈1×1023 W Hz−1[12] and of extragalactic origin.[13] Moreover, the source is of flat-spectrum type.[14][15]
A low-excitation
radio galaxy with 1.4 GHz
luminosity between 2 × 1023 and 3 × 1025 W Hz−1, PKS 2338+000 relies on its own halo mass.[16] Notably, the radio galaxy is quite young with an age estimated < 103 yr. When studied by
Chandra and
Multi-unit spectroscopic explorer (MUSE), the blistering gas are yet to meet expectations of cooled intracluster medium, of which the
entropy and cooling time for the pre-feedback cluster located 20 kpc from the main cluster falls below mature-feedback clusters with a factor of ~2. As for the
mechanical power of PKS 2338+000 is gauged to be ~1044 − 1045erg s−1, suggesting entropy levels would be reinstituted within a few million years.[17]
PKS 2338+000 has a twin-peaked narrow emission line and a binary core.[18] It is theorized as the brightest cluster galaxy, PKS 2338+000 might have been formed from melding of smaller
spiral and elliptical galaxies.[19] When these galaxies collide with each other,
tidal forces and
dynamical friction divides
kinetic energy into random form of
energies, allowing these galaxies to
merge together into a formless,
triaxial system resembling a giant elliptical galaxy like PKS 2338+000.[20][21]
Researchers found strong
Hα and [O II] λ3727
emission lines inside the optical spectra.[22] Despite being red and dead galaxy, the
star formation rate in PKS 2338+000 is under way, mainly being inhabited by a distinctive cluster environment that leads up to self-regulated
feedback cycle between the cooling process of
interstellar medium and by the activity.[23]
Rotational measure
PKS 2338+000 has a exorbitant
rotational measure. When researchers used a multifrequency single-dish observation with a 100-m
Effelsberg telescope, the values of the rotational measure in PKS 2338+000 is found to have a
rest frame that is significant compared to rest frame 1000 rad/m2. This means a vigorous
depolarisation at 21 cm and existence of dense medium encircling the galaxy with powerful
magnetic fields.[24]
Molecular gas content
Researchers also evaluated the role of radio activity in PKS 2338+000. To conduct the investigation, a massive
carbon oxide (CO) survey of similar radio galaxies (RGs) like PKS 2338+000, is conducted to control the galaxies'
molecular gas mass at different
epochs. They used a sample of 120 RGs representative of the
NVSS 1.4 GHz survey, which the
flux is restricted at 0.4 Jy. Through the results at all epochs, the bulk of RGs have reservoirs found unnoticeable. Researchers also saw a swift increase in the H2mass content of the CO-detected RGs at redshifts. At 1 < z < 2.5, one-fourth of the RGs including PKS 2338+000 have a high concentration of molecular gas due to
simulations indicating a particular halo mass of the epoch. Such galaxies have the likelihood of being "normal" or even starburst hosts. Overall, the estimated molecular
gas reservoirs for PKS 2338+000 is 107 ≲ MH2 ≲ 1010 M⊙. This a fraction lower of ~4, in prepositional to type 1 and 2 AGN both pure and with less star formations, like the simulations.[25]
H I absorption
PKS 2338+000 has a large kpc size radio source that is ten times more than expected. The source is estimated to be in the radio-power range of 1025.7 W Hz−1-1026.5 W Hz−1 and interconnected with the
H I absorption in the region. According to researchers who detected H I absorption in the radio source of PKS 2338+000, the radio continuum
emission is found unresolved at ~5 to 10 kpc when observed, but has an enlarged structure. Analyzing the H I 21 cm
absorption spectra of the detection to understand the morphology and
kinematics of H I, researchers found the absorption profiles are compounded of
widths between nulls spanning from ~60 km s−1 to 700 km s−1. The detections found, exhibits an astounding high H I
column density in the range ~1021/cm2-1022/cm2 for Tspin = 100 K with a unit covering
factor. The modelling of the absorption profile according to researchers, found a large part of absorption is compatible with absorption emerging from an H I disc. Despite showing strong radio power in PKS 2338+000, they failed to detect fast
outflows. However, the optical emission lines shows occupancy of disturbed gas in nuclear regions that has forms of wide and high
blueshifted emission-line components. Since these detections are considered
low-ionisation, it is possible the interruption of gas is caused by the galaxy's own radio jets.[26]