IRAS 19254-7245, more commonly referred as the "Superantennae", are a pair of interacting galaxies located in the constellation of Pavo. It is located 820 million light years from Earth.[1] It is an ultraluminous infrared galaxy and a Seyfert galaxy.
| IRAS 19254-7245 | |
|---|---|
.jpg) IRAS 19254-7245 aka the "Superantennae" as seen by DESI Legacy Surveys. | |
| Observation data (J2000 epoch) | |
| Constellation | Pavo |
| Right ascension | 19h 31m 21.40s |
| Declination | −72° 39′ 18.0″ |
| Redshift | 0.061709 |
| Heliocentric radial velocity | 18,500 km/s |
| Distance | 820 Mly (251.41 Mpc) |
| Apparent magnitude (V) | 0.28 |
| Apparent magnitude (B) | 0.37 |
| Characteristics | |
| Type | Merger, Sy2 |
| Notable features | luminous infrared galaxy |
| Other designations | |
| AM 1925-0724, IRAS F19254-7245, LEDA 84913, Superantennae, IRAS 19254-7245 | |
Characteristics
editIRAS 19254-7245 is classfied a galaxy merger. It is made up of two giant gas-rich spiral galaxies with a projected separation of ~ 2 kpc.[2] With a disturbed morphology, the galaxy contains two tidal tails found stretching outwards to a total extend of 350 kiloparsecs (kpc).[2][3] It is said to represent the nearby galaxy pair, NGC 4038/4039 known as the Antennae Galaxies hence its namesake. However the object is ~ 5 times larger and ~ 10 times more luminous than the pair thus being called the "Superantennae".[4]
The Superantennae also has total molecular gas detection of MH2 = 3.0 x 1010 Msun.[5] It is optically an Seyfert type II galaxy according to Mirabel and colleagues. ISO mid-infrared spectroscopy did detect a presence of an active galactic nucleus, although there is no clear indications of a dominated energy source.[6]
Double nucleus
editThe two galaxies in the Superantennae system each have a distinctive nucleus. The northern nucleus appears in a post star formation stage but however less luminous when seen in infrared rays.[7] It shows dynamical components like a broad-line component measuring ~ 2000-2500 km s-1 at full width at half maximum (FWHM) connected with the other nucleus, within the galaxy's inner arcmin. Not to mention, the northern nucleus contains high-velocity clouds and narrow components (FWHM < 500 km s-1) associated with its procreator discs.[8]
The southern nucleus of the Superantennae is active when studied at multiple wavelengths.[9] According to observations made by Berta, it shows spectrophotometric characteristics in agreement with young and old stellar populations in the southern nucleus. The two types constitutes ~ 35 and ~ 65 of the mass of the southern galaxy respectively.[2]
Further observations are made on the two nuclei of the Superantennae by Chandra X-ray Observatory. The northern nucleus shows absence of AGN activity. On the other hand, the AGN of the southern nucleus is embedded and is Compton-thick.[10] It has an absorbing column density higher than 1024 cm-2.[6] Furthermore, the southern nucleus has a candidate X-ray source located 8" south of it. The off-point source is found to have a 0.3-10 keV luminosity of ~ 6 x 1040 ergs-1 and is connected with the Superantennae.[10]
Prescence of maser emission
editThe Superantennae is known to show megamaser emission. According to Atacama Large Millimeter Array, an extremely luminous emission line of (6 x 104 LΘ) 183 GHz H2O 31,3 - 22,0. This is interpreted as H2O emission originating in the maser amplification inside warm and dense molecular gas based on its compact nature (≥200 parsecs).[11]
References
edit- ^ "Your NED Search Results". ned.ipac.caltech.edu. Retrieved 2024-09-24.
- ^ a b c Reunanen, J.; Tacconi-Garman, L. E.; Ivanov, V. D. (2007-11-19). "VLT/SINFONI integral field spectroscopy of the Super-antennae★". Monthly Notices of the Royal Astronomical Society. 382 (3): 951–959. doi:10.1111/j.1365-2966.2007.12438.x. ISSN 0035-8711.
- ^ Vanzi, L.; Bagnulo, S.; Floc'h, E. Le; Maiolino, R.; Pompei, E.; Walsh, W. (2002-05-01). "Multi-wavelength study of IRAS 19254-7245 – The Superantennae". Astronomy & Astrophysics. 386 (2): 464–471. doi:10.1051/0004-6361:20020291. ISSN 0004-6361.
- ^ Mirabel, L.F.; Lutz, D.; Maza, J. (1991). "The Superantennae". Astronomy and Astrophysics. 243: 367. Bibcode:1991A&A...243..367M. Retrieved 2024-09-24.
- ^ Colina, Luis; Lipari, Sebastian; Macchetto, F. (1991-09-01). "Massive Star Formation and Superwinds in IRAS 19254-7245 (The Superantennae)". The Astrophysical Journal. 379: 113. Bibcode:1991ApJ...379..113C. doi:10.1086/170489. ISSN 0004-637X.
- ^ a b Risaliti, G.; Maiolino, R.; Marconi, A.; Bassani, L.; Berta, S.; Braito, V.; Della Ceca, R.; Franceschini, A.; Salvati, M. (2003-08-26). "Revealing the Active Galactic Nucleus in the Superantennae through L -Band Spectroscopy". The Astrophysical Journal. 595 (1): L17–L20. doi:10.1086/378842. ISSN 0004-637X.
- ^ Berta, S.; Fritz, J.; Franceschini, A.; Bressan, A.; Pernechele, C. (2003-05-01). "Spatially-resolved spectrophotometric analysis and modelling of the Superantennae". Astronomy and Astrophysics. 403: 119–134. arXiv:astro-ph/0303259. Bibcode:2003A&A...403..119B. doi:10.1051/0004-6361:20030368. ISSN 0004-6361.
- ^ Bendo, George J.; Clements, David L.; Khan, Sophia A. (2009-10-01). "Spectroscopically and spatially resolved optical line emission in the Superantennae (IRAS 19254-7245)". Monthly Notices of the Royal Astronomical Society: Letters. 399 (1): L29–L33. doi:10.1111/j.1745-3933.2009.00717.x. ISSN 1745-3933.
- ^ Charmandaris, V.; Laurent, O.; Floc'h, E. Le; Mirabel, I. F.; Sauvage, M.; Madden, S. C.; Gallais, P.; Vigroux, L.; Cesarsky, C. J. (2002-08-01). "Mid-infrared observations of the ultraluminous galaxies IRAS 14348-1447, IRAS 19254-7245, and IRAS 23128-5919". Astronomy & Astrophysics. 391 (2): 429–440. doi:10.1051/0004-6361:20020879. ISSN 0004-6361.
- ^ a b Jia, Jianjun; Ptak, Andrew; Heckman, Timothy M.; Braito, Valentina; Reeves, James (2012-11-01). "A Chandra Observation of the Ultraluminous Infrared Galaxy IRAS 19254-7245 (the Superantennae): X-Ray Emission from the Compton-thick Active Galactic Nucleus and the Diffuse Starburst". The Astrophysical Journal. 759 (1): 41. arXiv:1205.0035. Bibcode:2012ApJ...759...41J. doi:10.1088/0004-637X/759/1/41. ISSN 0004-637X.
- ^ Imanishi, Masatoshi; Hagiwara, Yoshiaki; Horiuchi, Shinji; Izumi, Takuma; Nakanishi, Kouichiro (2021-01-06). "ALMA detection of millimetre 183 GHz H2O maser emission in the Superantennae galaxy at z ∼ 0.06". Monthly Notices of the Royal Astronomical Society: Letters. 502 (1): L79–L84. doi:10.1093/mnrasl/slab006. ISSN 1745-3925.