PG 1543+489: Difference between revisions

{{Short description|Quasar in the constellation of Boötes}}

{{Infobox galaxy|name=PG 1543+489|epoch=[[J2000.0]]|constellation name=[[Boötes]]|ra=15h 45m 30.24s|dec=+48d 46m 09.07s|z=0.399824|h_radial_v=119,864 [[kilometer per second|km/s]]|dist_ly=4.559 [[light-years|Gly]] (1379.8 [[Megaparsec|Mpc]])|appmag_v=0.051|appmag_b=0.067|sbrightness=16.5|type=Spiral; RQQ, AGN|notes=[[Luminous infrared galaxy]], [[Seyfert galaxy]]|names=[[IRAS]] F15439+4855, [[ROSAT|RX]] J1545.5+4846, [[Principal Galaxies Catalogue|PGC]] 2325245, INTREF 656, [[2MASS]]i J1545302+484609, [[XMM-Newton|2XMM]] J154530.3+484608, [[Quasar|QSO]] B1544+4855, 1AXG J154530+4845|image=File:SDSS image of PG 1543+489.jpg|caption=PG 1543+489 captured by [[Sloan Digital Sky Survey|SDSS]]}}

 

 

== Characteristics ==

 

== Observations ==

Researchers also found a peculiar feature in PG 1543+489. The quasar shows a [[blueshift]] of the [O III] 5007 Å line that is 1150&nbsp;km s⁻¹ with respect to the systemic [[velocity]] of the galaxy as well as the blue [[asymmetry]] of its profile.<ref name=":1" /> The large [O III] blueshift or so-called 'blue outliers' by researchers, is found theoretically interpreted by the end result of intense outflows whose receding parts are obscured by an optically thick [[Accretion disk|accretion disc]]<ref>{{Cite journal |last1=Zamanov |first1=R. |last2=Marziani |first2=P. |last3=Sulentic |first3=J. W. |last4=Calvani |first4=M. |last5=Dultzin-Hacyan |first5=D. |last6=Bachev |first6=R. |date=2002-09-01 |title=Kinematic Linkage between the Broad- and Narrow-Line-emitting Gas in Active Galactic Nuclei |url=https://ui.adsabs.harvard.edu/abs/2002ApJ...576L...9Z |journal=The Astrophysical Journal |volume=576 |issue=1 |pages=L9–L13 |doi=10.1086/342783 |arxiv=astro-ph/0207387 |bibcode=2002ApJ...576L...9Z |issn=0004-637X}}</ref> or possibly a scenario which the [[Active galactic nucleus|narrow-line region]] clouds are entrained by [[Acceleration|decelerating]] winds, potentially associated with the high Eddington ratio typical of the 'blue outliers'.<ref>{{Citation |last1=Pronik |first1=V. I. |title=The Excitation Mechanism of Metastable Levels and Variability of Oxygen Forbidden Lines 4959+5007 Å [OIII] in the Seyfert Nuclei |date=1987 |work=Observational Evidence of Activity in Galaxies |pages=227–233 |url=http://dx.doi.org/10.1007/978-94-009-3851-9_36 |access-date=2024-06-20 |place=Dordrecht |publisher=Springer Netherlands |isbn=978-90-277-2474-8 |last2=Pronik |first2=I. I.|doi=10.1007/978-94-009-3851-9_36 |doi-broken-date=2024-06-21 }}</ref><ref>{{Cite journal |last1=Vignali |first1=Cristian |last2=Piconcelli |first2=Enrico |last3=Bianchi |first3=Stefano |last4=Miniutti |first4=Giovanni |date=2008-08-01 |title=On the peculiar properties of the narrow-line quasar PG 1543+489 |journal=Monthly Notices of the Royal Astronomical Society |volume=388 |issue=2 |pages=761–769 |doi=10.1111/j.1365-2966.2008.13438.x |doi-access=free |arxiv=0805.1227 |bibcode=2008MNRAS.388..761V |issn=0035-8711}}</ref>

 

== Absorption system ==

Through observations from [[Hubble Space Telescope]], researchers were able to find an [[Absorption line|absorption-line]] system at z = 0.07489. Looking at it, they found the [[Line of sight|sightline]] passes within ρ = 66 kpc of an edge-on 2{L}* [[Disc galaxy|disk galaxy]] at a similar redshift, belonging to four other galaxies in the group within ρ = 160 kpc. From the absorption-line system, they detected H I [log N(H I/cm-2) = 19.12 ± 0.04] as well as N I, Mg II, Si II, and Si III, from which we measure a gas-phase abundance of [N/H] = -1.0 ± 0.1. The [[photoionization]] models indicate that the [[nitrogen]]-to-[[silicon]] relative abundance is solar, yet [[magnesium]] is found underabundant by a factor of ≈2. By extracting out its rotational curve and reporting [[emission-line]] spectroscopy of the nearby galaxy, researchers suggests the [[metallicity]] is ≈8× higher compared to [N/H] in the absorber. Interestingly, the absorber velocities in the galaxy suggests gas at ρ = 66 kpc is corotating with the galaxy's [[stellar disk]], possibly with an inflow component. Although indicating the sub-damped [[Lyman-alpha|Lyα]] absorber system is responsible in causing cold [[Accretion (astrophysics)|accretion]] flow, the absorber abundance patterns are quite peculiar. Researchers hypothesized gas was probably ejected from its home galaxy or result of [[Glossary of astronomy|tidal debris]] from interactions between the group galaxies, with solar nitrogen abundance, but mixed with the gas in the [[Warm–hot intergalactic medium|circumgalactic medium]] or group. If the gas is bound to the nearby galaxy, this system may become an example of the gas "recycling" as predicted by theoretical galaxy [[simulation]]s.<ref>{{Cite journal |last1=Frye |first1=Brenda L. |last2=Bowen |first2=David V. |last3=Tripp |first3=Todd M. |last4=Jenkins |first4=Edward B. |last5=Pettini |first5=Max |last6=Ellison |first6=Sara L. |date=2019-02-01 |title=A Sub-damped Lyα Absorber with Unusual Abundances: Evidence of Gas Recycling in a Low-redshift Galaxy Group |journal=The Astrophysical Journal |volume=872 |issue=2 |pages=129 |doi=10.3847/1538-4357/ab0083 |doi-access=free |arxiv=1901.08147 |bibcode=2019ApJ...872..129F |issn=0004-637X}}</ref>

 

== References ==