I Zwicky 1

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I Zwicky 1
A picture of I ZW 1 taken by HST.jpg
Hubble Space Telescope image of I Zwicky 1
Observation data (J2000 epoch)
Constellation Pisces
Right ascension 00h 53m 34.94s
Declination +12d 41m 36.20s
Redshift 0.061169
Heliocentric radial velocity 18,338 km/s
Distance 847 Mly (259.7 Mpc)
Apparent magnitude  (V)0.43
Apparent magnitude  (B)0.54
Surface brightness 14.4
Characteristics
Type Sa;Sy1, Sbrst
Size0.5' x 0.5'
Notable features Seyfert galaxy containing a quasar
Other designations
UGC 545, PG 0050+124, PGC 3151, IRAS 00509+1225, RBS 0129, 2E 209, PHL 3072, Mrk 1502, Mrk 9009, NVSS J005334+124133

I Zwicky 1 (shortened to I Zw 1), also known as UGC 545, is a galaxy located in the constellation Pisces. It is located 847 million light-years from Earth [1] and is said to be the nearest quasar (QSO) due to its high optical nuclear luminosity of MV = -23.8 mag. [2]

Contents

Discovery

I Zwicky 1 was discovered by Fritz Zwicky in 1964. According to Zwicky, the object is classified as a compact galaxy, whom he commented it as "variable blue spherical, very compact, with a patchy halo. It is listed as the first object in the Zwicky catalogue. [3] At the redshift of 0.0611, [4] I Zwicky 1 shows spectral properties of high-redshift quasars that are blueshifted by 1350 km-1 according to the study conducted by Buson & Ulrich in 1990. [5]

The photometric history of I Zwicky 1, dates back to 1909, where it has been investigated on Harvard photographic plates. The available data indicates the galaxy is variable and probably undergoes outbursts of about 0.7 mag above a brightness level that is itself variable by about 0.7 mag. [6]

Characteristics

Sloan Digital Sky Survey of I Zwicky 1 SDSS image of I Zw 1.png
Sloan Digital Sky Survey of I Zwicky 1

The nucleus of I Zwicky 1 is found to be active. It is classified as a prototypical narrow-line Seyfert 1 galaxy [7] [8] [9] and contains high amounts of X-ray luminosity. [10] [11] The galaxy contains a peculiar spectrum, which in addition to the usual broad and narrow line regions, there are two emission regions emitting broad and blue shifted [O III] lines making it a peculiarly interesting object. [12] The QSO sits inside its host galaxy which is revealed to be a face-on spiral galaxy. It shows two asymmetric spiral arms and knots of star formation. [3] This makes I Zwicky 1 an ideal candidate for studying properties of QSO hosts. [2] It is also possible that certain tidal interactions triggers activity in I Zwicky 1, both starburst and QSO. [13]

I Zwicky 1 is classified a Markarian galaxy (designated both Mrk 1502 and Mrk 9009). Compared to other galaxies, the nucleus emits excessive amounts of ultraviolet rays. [14] This is caused by undergoing a strong starburst located in the central ring-like area of the galaxy. [3]

Further study on I Zwicky 1

I Zwicky 1 shows existence of V-, R-, and H-bands [15] [16] with sturdy carbon monoxide (CO) featured in the J = 1-0 and J = 2-1 lines. When further observed, researchers found that the J = 1-0 line is brighter compared to the J = 2-1 line found with less luminosity. Given location in galactic molecular clouds, the carbon monoxide must be larger on the scale of the 26 kpc J = 1-0 beam size, with optical depth and being thermalized. [17]

Researchers who studied interstellar medium and star formation, found out a two-component model is required for I Zwicky 1 in which 2/3 of the far-infrared brightness originates in the disk and 1/3 originates from the nucleus. The star-forming rate, efficiency of the disk and the nucleus of I Zwicky 1 was estimated by researchers, whom they found that the values are similar to the luminosity of galaxies studied by IRAS. Overall, the disc star-formation, is closer to topmost values of ~30 L_sun_/M_sun_ that is found inside galactic star-forming regions of the Milky Way such as M17 or W51. When looking at its nuclear near-infrared colors analysis, researchers suggest I Zwicky 1 has a combined quasar nucleus and defunct stellar component that matches about 10%-20% of the flux density at 2.2 microns. [18] This suggests the size of I Zwicky 1's molecular bulge is estimated to be 1" to 2" (1.2-2.4 kpc). But only the nucleus is revealed through optical spectrum and large X-ray luminosity. [18]

Millimeter Spectroscopy

Further studies showed the mapping of 12CO (10) line emission in I Zwicky 1 whom researchers conducted observations with Institut de Radio Astronomie Millimetrique (IRAM) millimeter interferometer on the Plateau de Bure, France, between January and February 1995. [19] There, they placed four 15 m antennas in four different configurations. With 24 baselines provided by the four 15 m antennas, ranging from 24 to 288 m in length, they were supplied by SIS receivers with single-sideband (SSB) system temperatures of 170 K above the atmosphere. Located at redshift 0.0611, the observed frequency of I Zwicky 1 was 108.633 GHz.

The CO maps were seen by the observations from IRAM 30m telescope. This resolution of a synthesized beam was uniform weighted of 19, but 5 resolution CLEAN maps (natural weighting) were made by spectral resolutions of 10 km s−1 and 40 km s−1 to examine the extended disk structure and velocity field. For the core component, researchers used the 19 resolution CLEANed maps with a spectral resolution of 20 km s−1. To investigate the structure dynamics of the nucleus, which they reckoned these velocity maps together with p-v diagrams alongside major and minor kinematic axes of I Zwicky 1. [2]

Near-Infrared Spectroscopy and Imaging

I Zwicky 1 was observed by K-band (2.20 m) in January, 1995 with a MPE imaging spectrometer making use of 3D images [20] with a 3.6 m telescope in Calar Alto, Spain. The observations in the H-band (1.65 m) on the other hand, were carried out in December 1995, at the William Herschel Telescope located in La Palma, Canary Islands. From two observations, researchers found that the image scale was 05 pixel−1 and total integration time on source was 4200 s and 1530 s for the K-band and H-band respectively. [2]

Molecular gas properties

The properties of the molecular gas are important for acknowledging the total star formation and powering AGNs, given molecular clouds are the major reservoirs for such occurrences. According to researchers, looking inside the spiral arms of the QSO host galaxy, they detected the molecular line emission. Seeing this, they were able to break up the line emission into a separate core and disk components. Through analyzing the velocity field, a circumnuclear ring of molecular gas is found. It has a similar size to starburst rings in nearby galaxies. With a spatial resolution of 19 (2.2 kpc), no signs of gas is suggested streaming straight to the nucleus. [2]

Comparison of starburst rings

In a study where starburst rings are observed in galaxies, [21] the rings in I Zwicky 1 are suggested to be formed by gravitational interactions, because of high rates of stars and gas. These rings are detected in midinfrared continuum, near-infrared colors, molecular gas line emission, and H line emission. Although, the overall structure of these rings aren't even, it is feasible they are formed by two twisted spiral arms on every side of the nucleus. [2] To see whether the rings are unique or ordinary, researchers found two other galaxies, NGC 7552 and NGC 7469. They found the ring properties are alike to one another for all three galaxies. But there is a difference in total bolometric luminosity which might be linked to the internal structure of the rings, and to a certain, starburst regions are fueled within the ring region. [2]

The starburst rings of I Zwicky 1 are 3 times older compared to those in NGC 7552 and NGC 7469. Using the comparison, the molecular ring researchers detected in the 12CO(10) line emission, might contain starburst like other circumnuclear rings. This indicates the luminosity fraction observed for QSOs and Seyfert galaxies is mainly caused by circumnuclear starbursts in the centers of host galaxies, and that the AGNs aren't only responsible for energy output overall in the optical and infrared light. [2] Such star formation activity contributed to bolometric luminosity only range about 10% to 50% in I Zwicky 1, compared to observations for NGC 7469. [22]

To sum things up, a young starburst is associated with this circumnuclear ring. The properties of this starburst ring in I Zwicky 1, are similar to nuclear activity sources. When looking at similarities, the rings are a possible common phenomenon that contributes significant fraction to luminosity in central regions. [2]

Supermassive black hole

The supermassive black hole in I Zwicky 1, has an estimated solar mass of M. = 9.30+1.26- 1.38 x 106 M○ when researchers calculated the mean spectra. This suggests the accretion rate is 203.9+61.0-65.8 L edd c-2, indicating there is a super-Eddington accretor, where LEdd is the Eddington luminosity and c is the speed of light. By splitting up Hubble Space Telescope images, researchers find the stellar mass of the bulge of its host galaxy is similar to log(M budge/M○ = 10.92 + 0.07. Looking at these values, they suggest the black hole has bulge mass ratio of ~10−4, which is smaller when compared to classical bulges of elliptical galaxies. [23]

An article published in 2021, found out according to observations by ESA's XMM-Newton and NASA's NuSTAR space telescopes, the black hole emits out X-ray flares from the region. Further analysis by researches showed, brief flashes of photons that are found consistent in the re-emergence of emission, proving they had reverberated from black hole's accretion disk in form light echoes, which are subsequently distorted and extended by the galaxy's strong gravitational field. [24] [25]

Related Research Articles

An active galactic nucleus (AGN) is a compact region at the center of a galaxy that emits a significant amount of energy across the electromagnetic spectrum, with characteristics indicating that this luminosity is not produced by the stars. Such excess, non-stellar emissions have been observed in the radio, microwave, infrared, optical, ultra-violet, X-ray and gamma ray wavebands. A galaxy hosting an AGN is called an active galaxy. The non-stellar radiation from an AGN is theorized to result from the accretion of matter by a supermassive black hole at the center of its host galaxy.

<span class="mw-page-title-main">Seyfert galaxy</span> Class of active galaxies with very bright nuclei

Seyfert galaxies are one of the two largest groups of active galaxies, along with quasar host galaxies. They have quasar-like nuclei with very high surface brightnesses whose spectra reveal strong, high-ionisation emission lines, but unlike quasars, their host galaxies are clearly detectable.

<span class="mw-page-title-main">NGC 4194</span> Interacting galaxy pair in the constellation of Ursa Major

NGC 4194, the Medusa merger, is a galaxy merger in the constellation Ursa Major about 128 million light-years (39.1 Mpc) away. It was discovered on April 2, 1791 by German-British astronomer William Herschel. Due to its disturbed appearance, it is object 160 in Halton Arp's 1966 Atlas of Peculiar Galaxies.

<span class="mw-page-title-main">NGC 4203</span> Galaxy in the constellation Coma Berenices

NGC 4203 is the New General Catalogue identifier for a lenticular galaxy in the northern constellation of Coma Berenices. It was discovered on March 20, 1787 by English astronomer William Herschel, and is situated 5.5° to the northwest of the 4th magnitude star Gamma Comae Berenices and can be viewed with a small telescope. The morphological classification of NGC 4203 is SAB0−, indicating that it has a lenticular form with tightly wound spiral arms and a weak bar structure at the nucleus.

<span class="mw-page-title-main">NGC 7469</span> Galaxy located in the constellation Pegasus

NGC 7469 is an intermediate spiral galaxy in the constellation of Pegasus. NGC 7469 is located about 200 million light-years away from Earth, which means, given its apparent dimensions, that NGC 7469 is approximately 90,000 light-years across. It was discovered by William Herschel on November 12, 1784.

<span class="mw-page-title-main">NGC 7130</span> Galaxy in the constellation Piscis Austrinus

NGC 7130 is a spiral galaxy located in the constellation Piscis Austrinus. It is located at a distance of about 220 million light years from Earth, which, given its apparent dimensions, means that NGC 7130 is about 100,000 light years across. It was discovered by John Herschel on September 25, 1834, and discovered independently by Lewis Swift on September 17, 1897. The location of the galaxy given in the New General Catalogue was off by 30 arcminutes in declination from the location of the galaxy.

<span class="mw-page-title-main">NGC 985</span> Ring galaxy in the constellation Cetus

NGC 985 is a ring galaxy in the constellation of Cetus. It is located about 550 million light years away from Earth, which means, given its apparent dimensions, that NGC 985 is approximately 160,000 light years across. It was discovered by Francis Leavenworth in 1886. It is a type 1 Seyfert galaxy.

<span class="mw-page-title-main">NGC 1386</span> Galaxy in the constellation Eridanus

NGC 1386 is a spiral galaxy located in the constellation Eridanus. It is located at a distance of circa 53 million light years from Earth, which, given its apparent dimensions, means that NGC 1386 is about 50,000 light years across. It is a Seyfert galaxy, the only one in Fornax Cluster.

<span class="mw-page-title-main">NGC 2273</span> Galaxy in the constellation Lynx

NGC 2273 is a barred spiral galaxy located in the constellation Lynx. It is located at a distance of circa 95 million light years from Earth, which, given its apparent dimensions, means that NGC 2273 is about 100,000 light years across. It was discovered by Nils Dunér on September 15, 1867.

<span class="mw-page-title-main">NGC 7679</span> Galaxy in the constellation Pisces

NGC 7679 is a lenticular galaxy with a peculiar morphology in the constellation Pisces. It is located at a distance of about 200 million light years from Earth, which, given its apparent dimensions, means that NGC 7679 is about 60,000 light years across. It was discovered by Heinrich d'Arrest on September 23, 1864. The total infrared luminosity is 1011.05 L☉, and thus it is categorised as a luminous infrared galaxy. NGC 7679 is both a starburst galaxy and a Seyfert galaxy.

<span class="mw-page-title-main">NGC 4324</span> Galaxy in the constellation of Virgo

NGC 4324 is a lenticular galaxy located about 85 million light-years away in the constellation Virgo. It was discovered by astronomer Heinrich d'Arrest on March 4, 1862. NGC 4324 has a stellar mass of 5.62 × 1010M☉, and a baryonic mass of 5.88 × 1010M☉. The galaxy's total mass is around 5.25 × 1011M☉. NGC 4324 is notable for having a ring of star formation surrounding its nucleus. It was considered a member of the Virgo II Groups until 1999, when its distance was recalculated and it was placed in the Virgo W Group.

<span class="mw-page-title-main">IC 3528</span> Galaxy in the constellation Coma Berenices

IC 3528 is spiral galaxy located 660 million light-years away in the constellation of Coma Berenices. It lies near to another spiral galaxy NGC 4540, although the two of them are quite far. The object was discovered by Royal Harwood Frost on May 7, 1904. Although listed as a member in the Virgo Cluster Catalogue as VCC 1593, it is not a member of the Virgo cluster but a background galaxy.

<span class="mw-page-title-main">IC 3078</span> Galaxy located in Virgo

IC 3078 is a spiral galaxy with a ring structure located in Virgo. Its redshift is 0.066148, meaning IC 3078 is located 905 million light-years from Earth. With an apparent dimension of 0.50 x 0.5 arcmin, IC 3038 is about 133,000 light-years across. It was discovered by Royal Harwood Frost on May 7, 1904 and is listed in the Virgo Cluster catalogue as VCC 174. However, it is not a member of the Virgo Cluster, but instead a background galaxy.

<span class="mw-page-title-main">IRAS F11119+3257</span>

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<span class="mw-page-title-main">IRAS 09104+4109</span>

IRAS 09104+4109 is a galaxy located in the constellation Lynx. With a redshift of 0.440797, the light travel time for this galaxy, corresponds to 4.8 billion light-years from Earth. It is the brightest cluster galaxy in CDGS 25, also known as WHL J091345.5+405628 and a notable, unique ultraluminous infrared galaxy.

<span class="mw-page-title-main">PG 0844+349</span>

PG 0844+349, also known as TON 951, is a galaxy in the southern constellation Lynx, near the border of Cancer. Its redshift is 0.064000, putting the galaxy at 849 million light-years away from Earth.

<span class="mw-page-title-main">MRC 0406-244</span>

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<span class="mw-page-title-main">PKS 1402-012</span>

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<span class="mw-page-title-main">RIQ J1336+1725</span>

RIQ J1336+1725 also known as PB 4007 and PG 1333+177, is a quasar located in the constellation of Coma Berenices. At a low redshift of 0.55, the object is located 6.5 billion light-years from Earth. This quasar is known to have a Lyman edge region that is formed by its thermally emitting accretion disk.

<span class="mw-page-title-main">PG 1543+489</span>

PG 1543+489, also known as QSO B1544+4855 and PGC 2325245, is a quasar located in the constellation of Boötes. At the redshift of 0.399, the object is located 4.5 billion light-years away from Earth. It was first discovered in 1983, by researchers who presented 114 objects in the Palomar-Green bright quasar survey, as one of the best studied samples of active galactic nuclei (AGN).

References

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  2. 1 2 3 4 5 6 7 8 9 "Host Galaxy of QSO I Zw 1". iopscience.iop.org. arXiv: astro-ph/9801061 . doi:10.1086/305714 . Retrieved 2024-05-20.
  3. 1 2 3 "0050+124". quasar.square7.ch. Retrieved 2024-05-20.
  4. ↑ Condon, J. J.; Hutchings, J. B.; Gower, A. C. (1985-09-01). "HI emission from quasar host galaxies". The Astronomical Journal. 90: 1642–1647. Bibcode:1985AJ.....90.1642C. doi:10.1086/113870. ISSN   0004-6256.
  5. ↑ Buson, L. M.; Ulrich, M. -H. (1990-12-01). "The Ly-alpha and C IV lines in 10 low-redshift active galactic nuclei/quasars". Astronomy and Astrophysics. 240: 247. Bibcode:1990A&A...240..247B. ISSN   0004-6361.
  6. ↑ Usher, P. D.; Shen, B. S. P.; Barrett, J. W. (1971-05-01). "I ZW 1: a Variable Compact Galaxy". The Astrophysical Journal. 165: 647. Bibcode:1971ApJ...165..647U. doi:10.1086/150930. ISSN   0004-637X.
  7. ↑ Osterbrock, Donald E.; Martel, Andre (1993-09-01). "Spectroscopic Study of the CfA Sample of Seyfert Galaxies". The Astrophysical Journal. 414: 552. Bibcode:1993ApJ...414..552O. doi:10.1086/173102. ISSN   0004-637X.
  8. ↑ Gallo, L. C.; Boller, Th; Brandt, W. N.; Fabian, A. C.; Vaughan, S. (2004-04-01). "I Zw 1 observed with XMM-Newton - Low-energy spectral complexity, iron lines, and hard X-ray flares". Astronomy & Astrophysics. 417 (1): 29–38. arXiv: astro-ph/0312298 . Bibcode:2004A&A...417...29G. doi:10.1051/0004-6361:20034411. ISSN   0004-6361.
  9. ↑ Panda, Swayamtrupta; Santos, Denimara Dias dos (2021-11-29), "Revisiting the spectral energy distribution of I Zw 1 under the CaFe Project", Acta Astrophysica Taurica, 3 (1): 27, arXiv: 2111.01521 , Bibcode:2022AcAT....3a..27P, doi:10.31059/aat.vol3.iss1.pp27-34
  10. ↑ Kruper, J. S.; Urry, C. M.; Canizares, C. R. (1990-10-01). "Soft X-Ray Properties of Seyfert Galaxies. I. Spectra". The Astrophysical Journal Supplement Series. 74: 347. Bibcode:1990ApJS...74..347K. doi:10.1086/191503. ISSN   0067-0049.
  11. ↑ Boller, T.; Brandt, W. N.; Fink, H. (1996-01-01). "Soft X-ray properties of narrow-line Seyfert 1 galaxies". Astronomy and Astrophysics. 305: 53. arXiv: astro-ph/9504093 . Bibcode:1996A&A...305...53B. ISSN   0004-6361.
  12. ↑ Véron-Cetty, M.-P.; Joly, M.; Véron, P. (2004-04-01). "The unusual emission line spectrum of I Zw 1". Astronomy & Astrophysics. 417 (2): 515–525. arXiv: astro-ph/0312654 . Bibcode:2004A&A...417..515V. doi:10.1051/0004-6361:20035714. ISSN   0004-6361.
  13. ↑ Scharwächter, J.; Eckart, A.; Pfalzner, S. (2001-01-01). "Merger Properties of the Narrow-line Seyfert 1 Galaxy I Zw 1". Astronomische Gesellschaft Meeting Abstracts. 18: MS 05 22. Bibcode:2001AGM....18S0522S.
  14. ↑ Petrosian, Artashes; McLean, Brian; Allen, Ronald J.; MacKenty, John W. (2007-05-01). "Markarian Galaxies. I. The Optical Database and Atlas". The Astrophysical Journal Supplement Series. 170 (1): 33–70. Bibcode:2007ApJS..170...33P. doi:10.1086/511333. ISSN   0067-0049.
  15. ↑ Bothun, G. D.; Heckman, T. M.; Schommer, R. A.; Balick, B. (1984-09-01). "CCD imaging and neutral hydrogen emission in I ZW 1 and other low-redshift QSOs/AGNs". The Astronomical Journal. 89: 1293–1299. Bibcode:1984AJ.....89.1293B. doi:10.1086/113627. ISSN   0004-6256.
  16. ↑ Hutchings, J. B.; Crampton, D. (1990-01-01). "Images and Off-Nuclear Spectroscopy of QSOs". The Astronomical Journal. 99: 37. Bibcode:1990AJ.....99...37H. doi:10.1086/115309. ISSN   0004-6256.
  17. ↑ Barvainis, Richard; Alloin, Danielle; Antonucci, Robert (1989-02-01). "Detection of Strong Carbon Monoxide Emission from the Host Galaxy of the Quasar I ZW 1". The Astrophysical Journal. 337: L69. Bibcode:1989ApJ...337L..69B. doi:10.1086/185380. ISSN   0004-637X.
  18. 1 2 Eckart, A.; van der Werf, P. P.; Hofmann, R.; Harris, A. I. (1994-04-01). "Interstellar Medium and Star Formation in the Nearby QSO I ZW 1". The Astrophysical Journal. 424: 627. Bibcode:1994ApJ...424..627E. doi:10.1086/173919. ISSN   0004-637X.
  19. ↑ Guilloteau, S.; Delannoy, J.; Downes, D.; Greve, A.; Guelin, M.; Lucas, R.; Morris, D.; Radford, S. J. E.; Wink, J.; Cernicharo, J.; Forveille, T.; Garcia-Burillo, S.; Neri, R.; Blondel, J.; Perrigourad, A. (1992-09-01). "The IRAM interferometer on Plateau de Bure". Astronomy and Astrophysics. 262: 624. Bibcode:1992A&A...262..624G. ISSN   0004-6361.
  20. ↑ Weitzel, L.; Krabbe, A.; Kroker, H.; Thatte, N.; Tacconi-Garman, L. E.; Cameron, M.; Genzel, R. (1996-11-01). "3D: The next generation near-infrared imaging spectrometer". Astronomy and Astrophysics Supplement Series. 119 (3): 531–546. Bibcode:1996A&AS..119..531W. doi:10.1051/aas:1996266. ISSN   0365-0138.
  21. ↑ Buta, R.; Combes, F. (1996-01-01). "Galactic Rings". Fundamentals of Cosmic Physics. 17: 95–281. Bibcode:1996FCPh...17...95B.
  22. ↑ Genzel, R.; Weitzel, L.; Tacconi-Garman, L. E.; Blietz, M.; Cameron, M.; Krabbe, A.; Lutz, D.; Sternberg, A. (1995-05-01). "Infrared Imaging and Spectroscopy of NGC 7469". The Astrophysical Journal. 444: 129. Bibcode:1995ApJ...444..129G. doi:10.1086/175588. ISSN   0004-637X.
  23. ↑ Huang, Ying-Ke; Hu, Chen; Zhao, Yu-Lin; Zhang, Zhi-Xiang; Lu, Kai-Xing; Wang, Kai; Zhang, Yue; Du, Pu; Li, Yan-Rong; Bai, Jin-Ming; Ho, Luis C.; Bian, Wei-Hao; Yuan, Ye-Fei; Wang, Jian-Min (2019-05-08). "Reverberation Mapping of the Narrow-line Seyfert 1 Galaxy I Zwicky 1: Black Hole Mass". The Astrophysical Journal. 876 (2): 102. arXiv: 1904.06146 . Bibcode:2019ApJ...876..102H. doi: 10.3847/1538-4357/ab16ef . ISSN   0004-637X.
  24. ↑ Staff, News (2021-07-30). "Astronomers Detect Light Echoes Coming from Behind Supermassive Black Hole | Astronomy | Sci-News.com". Sci.News: Breaking Science News. Retrieved 2024-05-20.{{cite web}}: |first= has generic name (help)
  25. ↑ Wilkins, D. R.; Gallo, L. C.; Costantini, E.; Brandt, W. N.; Blandford, R. D. (2021-07-29). "Light bending and X-ray echoes from behind a supermassive black hole". Nature. 595 (7869): 657–660. arXiv: 2107.13555 . doi:10.1038/s41586-021-03667-0. ISSN   0028-0836.
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