NGC 4636

Last updated
NGC 4636
NGC4636 - SDSS DR14 (panorama).jpg
SDSS image of the elliptical galaxy NGC 4636.
Observation data (J2000 epoch)
Constellation Virgo
Right ascension 12h 42m 49.8s [1]
Declination +02° 41′ 16″ [1]
Redshift 0.003129 ± 0.000014 [1]
Heliocentric radial velocity 938 ± 4 km/s [1]
Distance 53 ± 11 Mly (16.3 ± 3.4 Mpc) [1]
Apparent magnitude  (V)9.4 [2]
Characteristics
Type E/S0_1 [1]
Apparent size  (V)6.0′ × 4.7′
Notable featuresStrong X-ray source
Other designations
UGC 7878, VCC 1939, CGCG 043-002, MCG +01-32-137, PGC 42734 [1]

NGC 4636 is an elliptical galaxy located in the constellation Virgo. It is a member of the NGC 4753 Group of galaxies, which is a member of the Virgo II Groups, a series of galaxies and galaxy clusters strung out from the southern edge of the Virgo Supercluster. [3] It is located at a distance of about 55 million light years from Earth, which, given its apparent dimensions, means that NGC 4636 is about 105,000 light years across.

Contents

It was discovered by William Herschel on February 23, 1784. [4] NGC 4636 lies one and a half degrees southwest of Delta Virginis. It can be viewed through a telescope at a ×23 magnification as a bright oval glow. It is part of the Herschel 400 Catalogue. [5]

Characteristics

The central part of NGC 4636 is circular and is surrounded by an elongated fainter envelope, containing a large number of globular clusters. [6] The galaxy has an active galactic nucleus (AGN) that has been categorised as LINER or a type 1.9 Seyfert galaxy. [7] The source of nuclear activity in galaxies is suggested to be a supermassive black hole that accretes material. NGC 4636 harbors a relatively small supermassive black hole with mass 7.9×107  M☉ , as inferred from the bulge velocity dispersion. [8]

Molecular gas

NGC 4636 by Hubble Space Telescope NGC 4636 color cutout hst 08686 07 wfpc2 f814w f547m pc sci.jpg
NGC 4636 by Hubble Space Telescope

When imaged in CO(2–1) there appear molecular clouds in NGC 4636. Cloud 1 is not associated with detectable optical emission and is out of the dust extinction map field of view, while cloud 2 is centered on a dust absorption knot and aligned with a ridge in the optical line emission map. The faint NGC 4636 ALMA continuum is in good agreement with the expected emission from cold dust, which would indicate that the dust content of NGC 4636 is fairly centrally located. The associated total molecular mass is 2.6×105  M☉ . [9]

The ultraviolet emission of NGC 4636 exhibits O vi emission, which is a tracer of gas cooling. The measured emission indicates a cooling rate of 0.3 M⊙ yr−1. [10] [11] Polycyclic aromatic hydrocarbons (PAH) emission was detected at 11.3 and 17 μm, as well as [Ne ii], [Ne iii], and [S iii] lines in the center of NGC 4636 (within re/8) using the Spitzer IRS. [12] The far infrared emission of the galaxy, as observed by the Infrared Space Observatory is 50 times more than expected based on stellar emission alone. This strongly suggests that there is dust, probably accreted in a recent merger with a gas-rich galaxy. [13] Hα observations reveal the presence of warm (T ~ 104 K) ionized gas in the inner kpc of NGC 4636. Spectra of this gas indicate irregular motion, with a typical velocity of 150–200 km/s. Hα maps of the galaxy core show the presence of a cavity in the distribution of the ionized gas encircled by a dense shell located at a distance of ~400 pc from the center. Again, the most plausible explanation is gas expansion caused by AGN activity. [9] [14] [15] [16]

In NGC 4636, the [C ii] emission extends to a radius of ~1 kpc and is centrally peaked. The velocities inferred from the [C ii] line are consistent with those measured for the Hα line. Finally, NGC 4636 has an excess of cold dust, approximately cospatial with the ionized and molecular gas. [17] [18] As above, this dust is expected be embedded in cold gas, to be protected against rapid sputtering. The extended dust distribution originates from the ejection of cold gas by AGN activity 10 Myr ago. [17]

Globular clusters

NGC 4636 is characterised by its large number of globular clusters, much larger than that of galaxies with similar size located not in the centre of galaxy clusters. The total number of globular clusters within a radius of 14 arcminutes is estimated to be 4,200 ± 120 and within 7 arcminutes is estimated to be 3,500 ± 170. [19] In comparison, 12,000 ± 800 globular clusters orbit around Messier 87, the giant elliptical galaxy at the centre of the Virgo Cluster, and 150–200 lie in and around the Milky Way. The number of globular clusters drops abruptly at 7 and 9 arcminutes, probably indicating the edge of the galaxy. [19]

The color distribution of the globular clusters in the galaxy is bimodal, a distribution that has been observed in other galaxies too. The globular clusters are characterised based on their color as blue or red. [19] The population of red clusters is higher. Similarly with color, the metallicity distribution is bimodal, with two peaks at [Fe/H] = −1.23(σ = 0.32) and −0.35(σ = 0.19). The ages of the globular clusters in NGC 4636 vary from 2 to 15 billion years, with a bit more than a quarter of the clusters having ages less than 5 billion years. It has been suggested that the younger clusters were formed during the merging of smaller galaxies with the elliptical galaxy. [20]

The velocity dispersion of the clusters is 231+15
−17 km/s, with the velocity dispersion of the blue clusters being slightly larger. [21] This velocity dispersion is similar to that of Messier 60, which is, however, a brighter galaxy. Comparing the velocity dispersion of the globular clusters with the stellar one it is calculated that mass-to-light ratio is not constant, but should increase as the galactocentric distance increases, indicating the existence of an extended dark matter halo in NGC 4636. [22] [23]

X-ray emission

Chandra image of the core of NGC 4636 with superimposed contours of Ha+[N ii] emission. White crosses mark the detected CO cloud positions. Chandra image of NGC 4636 with Ha+Nii contours.jpg
Chandra image of the core of NGC 4636 with superimposed contours of Hα+[N ii] emission. White crosses mark the detected CO cloud positions.

NGC 4636 is one of the most luminous nearby elliptical galaxies when observed in X-rays, with estimated X-ray flux of 1.8×1041 erg/s. A hot gas corona around the galaxy was first detected by the Einstein Observatory. [24] Based on the hot interstellar medium temperature profile, the total mass of the halo was estimated to be 1.5×1012  M☉ within a radius of 35 kpc. The percentage of non-luminous matter mass is estimated to be between 50% and 80% of the total galactic mass, implying an exceptionally low baryon fraction in NGC 4636 and the presence of a large dark matter halo. [25]

The halo of NGC 4636 has some unique features. Observations by the Chandra X-ray Observatory revealed symmetric, 8 kpc long structures within the halo that look like spiral arms. The arms are about 30 percent hotter than the surrounding gas cloud. [26] The arms form the rim of two large ellipsoid bubbles of hot gas. One more bubble-like feature has been detected about 2 kpc south of the northeastern arm. A weak radio source, elongated in the NE–SW direction, connects the NE and SW bubbles. These large bubbles are likely the result of shocks generated by the AGN jets. [27] It is possible that the bubbles have different ages, generated by different AGN outbursts, as indicated by the presence of radio-emitting plasma in one cavity, while the others are radio-quiet. [28]

NGC 4636 has an X-ray-bright core, having a radius of ~1 kpc. The core shows a central cavity surrounded by a bright edge. [27] Interestingly, the small X-ray cavity surrounds the ~1 kpc radio jet detected at 1.4 GHz [29] and is likely generated by the jet. Thus, the X-ray and radio observations point to a scenario in which gas may be currently outflowing in the central kpc of NGC 4636. [9]

There are 318 point X-ray sources in the field of NGC 4636. About 25% of them are identified as background sources. 77 of the sources match the location of globular clusters. No correlation was found between the X-ray luminosities of the matched point sources and the luminosity or color of the host GC candidates. The other point sources are low-mass X-ray binaries. [30]

Supernovae

Two supernova e have been observed in NGC 4636, the first being SN 1939 A. It was a type Ia supernova whose maximum magnitude was estimated to be 11.9. [31] [32] It was discovered by Fritz Zwicky. [33] In January 2020 another type Ia supernova, SN 2020ue, was discovered by Koichi Itagaki. [34]

Nearby galaxies

NGC 4636 is the foremost galaxy of the galaxy group known as the NGC 4636 group. Other members of the group include NGC 4457, NGC 4586, NGC 4587, NGC 4600, NGC 4665, and NGC 4688. [35] These galaxies, along with NGC 4753, Messier 61 and their groups form the southern boundary of the Virgo cluster. It can be difficult to determine which galaxies belong to which group especially around the southern edge of the Virgo cluster where there is a confusion of galaxies at different distances. [36] NGC 4636 has also been listed as a member of the Virgo Cluster.

See also

Related Research Articles

<span class="mw-page-title-main">Messier 87</span> Elliptical galaxy in the Virgo Galaxy Cluster

Messier 87 is a supergiant elliptical galaxy in the constellation Virgo that contains several trillion stars. One of the largest and most massive galaxies in the local universe, it has a large population of globular clusters—about 15,000 compared with the 150–200 orbiting the Milky Way—and a jet of energetic plasma that originates at the core and extends at least 1,500 parsecs, traveling at a relativistic speed. It is one of the brightest radio sources in the sky and a popular target for both amateur and professional astronomers.

<span class="mw-page-title-main">Centaurus A</span> Radio galaxy in the constellation Centaurus

Centaurus A is a galaxy in the constellation of Centaurus. It was discovered in 1826 by Scottish astronomer James Dunlop from his home in Parramatta, in New South Wales, Australia. There is considerable debate in the literature regarding the galaxy's fundamental properties such as its Hubble type and distance. NGC 5128 is one of the closest radio galaxies to Earth, so its active galactic nucleus has been extensively studied by professional astronomers. The galaxy is also the fifth-brightest in the sky, making it an ideal amateur astronomy target. It is only visible from the southern hemisphere and low northern latitudes.

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

The Sombrero Galaxy is a peculiar galaxy of unclear classification in the constellation borders of Virgo and Corvus, being about 9.55 megaparsecs from the Milky Way galaxy. It is a member of the Virgo II Groups, a series of galaxies and galaxy clusters strung out from the southern edge of the Virgo Supercluster. It has an isophotal diameter of approximately 29.09 to 32.32 kiloparsecs, making it slightly bigger in size than the Milky Way.

<span class="mw-page-title-main">Messier 49</span> Elliptical galaxy in the constellation Virgo

Messier 49 is a giant elliptical galaxy about 56 million light-years away in the equatorial constellation of Virgo. This galaxy was discovered by astronomer Charles Messier in 1777.

<span class="mw-page-title-main">Messier 89</span> Elliptical galaxy in the constellation Virgo

Messier 89 is an elliptical galaxy in the constellation Virgo. It was discovered by Charles Messier on March 18, 1781. M89 is a member of the Virgo Cluster of galaxies.

<span class="mw-page-title-main">NGC 3227</span> Galaxy in the constellation Leo

NGC 3227 is an intermediate spiral galaxy that is interacting with the dwarf elliptical galaxy NGC 3226. The two galaxies are one of several examples of a spiral with a dwarf elliptical companion that are listed in the Atlas of Peculiar Galaxies. Both galaxies may be found in the constellation Leo. It is a member of the NGC 3227 Group of galaxies, which is a member of the Leo II Groups, a series of galaxies and galaxy clusters strung out from the right edge of the Virgo Supercluster.

<span class="mw-page-title-main">Eyes Galaxies</span> Pair of galaxies in the constellation Virgo

The Eyes Galaxies are a pair of galaxies about 52 million light-years away in the constellation Virgo. The pair are members of the string of galaxies known as Markarian's Chain.

<span class="mw-page-title-main">NGC 4388</span> Galaxy in the constellation Virgo

NGC 4388 is an active spiral galaxy in the equatorial constellation of Virgo. It was discovered April 17, 1784 by Wilhelm Herschel. This galaxy is located at a distance of 57 million light years and is receding with a radial velocity of 2,524km/s. It is one of the brightest galaxies of the Virgo Cluster due to its luminous nucleus. NGC 4388 is located 1.3° to the west of the cluster center, which translates to a projected distance of ≈400 kpc.

<span class="mw-page-title-main">NGC 3862</span> Galaxy in the constellation Leo

NGC 3862 is an elliptical galaxy located 300 million light-years away in the constellation Leo. Discovered by astronomer William Herschel on April 27, 1785, NGC 3862 is an outlying member of the Leo Cluster.

<span class="mw-page-title-main">NGC 3311</span> Galaxy in the constellation Hydra

NGC 3311 is a super-giant elliptical galaxy located about 190 million light-years away in the constellation Hydra. The galaxy was discovered by astronomer John Herschel on March 30, 1835. NGC 3311 is the brightest member of the Hydra Cluster and forms a pair with NGC 3309 which along with NGC 3311, dominate the central region of the Hydra Cluster.

<span class="mw-page-title-main">NGC 708</span> Galaxy in the constellation Andromeda

NGC 708 is an elliptical galaxy located 240 million light-years away in the constellation Andromeda and was discovered by astronomer William Herschel on September 21, 1786. It is classified as a cD galaxy and is the brightest member of Abell 262. NGC 708 is a weak FR I radio galaxy and is also classified as a type 2 Seyfert galaxy.

<span class="mw-page-title-main">NGC 720</span> Galaxy in the constellation Cetus

NGC 720 is an elliptical galaxy located in the constellation Cetus. It is located at a distance of circa 80 million light years from Earth, which, given its apparent dimensions, means that NGC 720 is about 110,000 light years across. It was discovered by William Herschel on October 3, 1785. The galaxy is included in the Herschel 400 Catalogue. It lies about three and a half degrees south and slightly east from zeta Ceti.

<span class="mw-page-title-main">NGC 1380</span> Galaxy in the constellation Fornax

NGC 1380 is a lenticular galaxy located in the constellation Fornax. It is located at a distance of circa 60 million light years from Earth, which, given its apparent dimensions, means that NGC 1380 is about 85,000 light years across. It was discovered by James Dunlop on September 2, 1826. It is a member of the Fornax Cluster.

<span class="mw-page-title-main">NGC 759</span> Galaxy in the constellation Andromeda

NGC 759 is an elliptical galaxy located 230 million light-years away in the constellation Andromeda. NGC 759 was discovered by astronomer by Heinrich d'Arrest on September 17, 1865. It is a member of Abell 262.

<span class="mw-page-title-main">NGC 5846</span> Galaxy in the constellation Virgo

NGC 5846 is an elliptical galaxy located in the constellation Virgo. It is located at a distance of circa 90 million light years from Earth, which, given its apparent dimensions, means that NGC 5846 is about 110,000 light years across. It was discovered by William Herschel on February 24, 1786. It lies near 110 Virginis and is part of the Herschel 400 Catalogue. It is a member of the NGC 5846 Group of galaxies, itself one of the Virgo III Groups strung out to the east of the Virgo Supercluster of galaxies.

<span class="mw-page-title-main">IC 1459</span> Elliptical galaxy in the constellation of Grus

IC 1459 is an elliptical galaxy located in the constellation Grus. It is located at a distance of circa 85 million light-years from Earth, which, given its apparent dimensions, means that IC 1459 is about 130,000 light-years across. It was discovered by Edward Emerson Barnard in 1892.

<span class="mw-page-title-main">NGC 4278</span> Galaxy in the constellation Coma Berenices

NGC 4278 is an elliptical galaxy located in the constellation Coma Berenices. It is located at a distance of circa 55 million light years from Earth, which, given its apparent dimensions, means that NGC 4278 is about 65,000 light years across. It was discovered by William Herschel on March 13, 1785. NGC 4278 is part of the Herschel 400 Catalogue and can be found about one and 3/4 of a degree northwest of Gamma Comae Berenices even with a small telescope.

<span class="mw-page-title-main">NGC 4294</span> Galaxy in the constellation Virgo

NGC 4294 is a barred spiral galaxy with flocculent spiral arms located about 55 million light-years away in the constellation Virgo. The galaxy was discovered by astronomer William Herschel on March 15, 1784 and is a member of the Virgo Cluster.

<span class="mw-page-title-main">NGC 4302</span> Galaxy in the constellation Coma Berenices

NGC 4302 is an edge-on spiral galaxy located about 55 million light-years away in the constellation Coma Berenices. It was discovered by astronomer William Herschel on April 8, 1784 and is a member of the Virgo Cluster.

<span class="mw-page-title-main">NGC 4318</span> Galaxy in the constellation Virgo

NGC 4318 is a small lenticular galaxy located about 72 million light-years away in the constellation Virgo. It was discovered by astronomer John Herschel on January 18, 1828. NGC 4318 is a member of the Virgo W′ group, a group of galaxies in the background of the Virgo Cluster that is centered on the giant elliptical galaxy NGC 4365.

References

  1. 1 2 3 4 5 6 7 "NASA/IPAC Extragalactic Database". Results for NGC 4636. Retrieved 2016-01-18.
  2. ↑ "Revised NGC Data for NGC 4636". spider.seds.org. Retrieved 25 November 2018.
  3. ↑ "The Virgo III Groups". Atlas of the Universe. Retrieved 2010-11-27.
  4. ↑ Seligman, Courtney. "NGC 4636 (= PGC 42734)". Celestial Atlas. Retrieved 19 November 2018.
  5. ↑ O'Meara, Steve (2007). Herschel 400 Observing Guide. Cambridge University Press. p. 150. ISBN   9780521858939.
  6. ↑ Sandage, A., Bedke, J. (1994), The Carnegie Atlas of Galaxies. Volume I, Carnegie Institution of Washington
  7. ↑ Ho, Luis C.; Filippenko, Alexei V.; Sargent, Wallace L. W.; Peng, Chien Y. (October 1997). "A Search for "Dwarf" Seyfert Nuclei. IV. Nuclei with Broad Hα Emission". The Astrophysical Journal Supplement Series. 112 (2): 391–414. arXiv: astro-ph/9704099 . Bibcode:1997ApJS..112..391H. doi:10.1086/313042. S2CID   15256980.
  8. ↑ Merritt, D.; Ferrarese, L. (21 January 2001). "Black hole demographics from the M bullet - relation". Monthly Notices of the Royal Astronomical Society. 320 (3): L30–L34. arXiv: astro-ph/0009076 . doi: 10.1046/j.1365-8711.2001.04165.x .
  9. 1 2 3 Temi, Pasquale; Amblard, Alexandre; Gitti, Myriam; Brighenti, Fabrizio; Gaspari, Massimo; Mathews, William G.; David, Laurence (27 April 2018). "ALMA Observations of Molecular Clouds in Three Group-centered Elliptical Galaxies: NGC 5846, NGC 4636, and NGC 5044". The Astrophysical Journal. 858 (1): 17. arXiv: 1711.10630 . Bibcode:2018ApJ...858...17T. doi: 10.3847/1538-4357/aab9b0 . S2CID   54062372. CC-BY icon.svg This article contains quotations from this source, which is available under the Creative Commons Attribution 3.0 Unported (CC BY 3.0) license.
  10. ↑ Bregman, Joel N.; Miller, Eric D.; Irwin, Jimmy A. (1 June 2001). "The Detection of a Cooling Flow Elliptical Galaxy from O [CSC]vi[/CSC] Emission". The Astrophysical Journal. 553 (2): L125–L128. arXiv: astro-ph/0104317 . doi: 10.1086/320675 .
  11. ↑ Bregman, Joel N.; Miller, Eric D.; Athey, Alex E.; Irwin, Jimmy A. (20 December 2005). "O VI in Elliptical Galaxies: Indicators of Cooling Flows". The Astrophysical Journal. 635 (2): 1031–1043. arXiv: astro-ph/0511284 . Bibcode:2005ApJ...635.1031B. doi:10.1086/497421. S2CID   5336177.
  12. ↑ Rampazzo, R.; Panuzzo, P.; Vega, O.; Marino, A.; Bressan, A.; Clemens, M. S. (11 June 2013). "A Spitzer–IRS spectroscopic atlas of early-type galaxies in the Revised Shapley–Ames Catalog". Monthly Notices of the Royal Astronomical Society. 432 (1): 374–403. arXiv: 1303.4584 . Bibcode:2013MNRAS.432..374R. doi:10.1093/mnras/stt475. S2CID   119266149.
  13. ↑ Temi, Pasquale; Mathews, William G.; Brighenti, Fabrizio; Bregman, Jesse D. (10 March 2003). "Dust in Hot Gas: Far-Infrared Emission from Three Local Elliptical Galaxies". The Astrophysical Journal. 585 (2): L121–L124. arXiv: astro-ph/0301452 . Bibcode:2003ApJ...585L.121T. doi:10.1086/374326. S2CID   6175517.
  14. ↑ Caon, Nicola; Macchetto, Duccio; Pastoriza, Miriani (March 2000). "A Survey of the Interstellar Medium in Early-Type Galaxies. III. Stellar and Gas Kinematics". The Astrophysical Journal Supplement Series. 127 (1): 39–58. Bibcode:2000ApJS..127...39C. doi:10.1086/313315. hdl: 10183/109051 . S2CID   53492991.
  15. ↑ Werner, N.; Oonk, J. B. R.; Sun, M.; Nulsen, P. E. J.; Allen, S. W.; Canning, R. E. A.; Simionescu, A.; Hoffer, A.; Connor, T.; Donahue, M.; Edge, A. C.; Fabian, A. C.; von der Linden, A.; Reynolds, C. S.; Ruszkowski, M. (11 April 2014). "The origin of cold gas in giant elliptical galaxies and its role in fuelling radio-mode AGN feedback". Monthly Notices of the Royal Astronomical Society. 439 (3): 2291–2306. arXiv: 1310.5450 . Bibcode:2014MNRAS.439.2291W. doi:10.1093/mnras/stu006. S2CID   53953986.
  16. ↑ Ahoranta, Jussi; Finoguenov, Alexis; Pinto, Ciro; Sanders, Jeremy; Kaastra, Jelle; de Plaa, Jelle; Fabian, Andrew (18 August 2016). "Observations of asymmetric velocity fields and gas cooling in the NGC 4636 galaxy group X-ray halo". Astronomy & Astrophysics. 592: A145. arXiv: 1607.07444 . Bibcode:2016A&A...592A.145A. doi:10.1051/0004-6361/201527523. S2CID   59029532.
  17. 1 2 Temi, Pasquale; Brighenti, Fabrizio; Mathews, William G. (10 May 2007). "Far-Infrared Spitzer Observations of Elliptical Galaxies: Evidence for Extended Diffuse Dust". The Astrophysical Journal. 660 (2): 1215–1231. arXiv: astro-ph/0701431 . Bibcode:2007ApJ...660.1215T. doi:10.1086/513690. S2CID   8819240.
  18. ↑ Mathews, William G.; Temi, Pasquale; Brighenti, Fabrizio; Amblard, Alexandre (11 April 2013). "Variations of Mid- and Far-Infrared Luminosities Among Early-Type Galaxies: Relation to Stellar Metallicity and Cold Dust". The Astrophysical Journal. 768 (1): 28. arXiv: 1303.3350 . Bibcode:2013ApJ...768...28M. doi:10.1088/0004-637X/768/1/28. S2CID   118646459.
  19. 1 2 3 Dirsch, B.; Schuberth, Y.; Richtler, T. (14 March 2005). "A wide-field photometric study of the globular cluster system of NGC 4636". Astronomy & Astrophysics. 433 (1): 43–56. arXiv: astro-ph/0503283 . Bibcode:2005A&A...433...43D. doi:10.1051/0004-6361:20035737. S2CID   14017938.
  20. ↑ Park, Hong Soo; Lee, Myung Gyoon; Hwang, Ho Seong; Kim, Sang Chul; Arimoto, Nobuo; Yamada, Yoshihiko; Tamura, Naoyuki; Onodera, Masato (10 November 2012). "The Globular Cluster System of NGC 4636 and Formation of Globular Clusters in Giant Elliptical Galaxies". The Astrophysical Journal. 759 (2): 116. arXiv: 1209.3890 . Bibcode:2012ApJ...759..116P. doi:10.1088/0004-637X/759/2/116. S2CID   118512169.
  21. ↑ Park, Hong Soo; Lee, Myung Gyoon; Hwang, Ho Seong; Arimoto, Nobuo; Tamura, Naoyuki; Onodera, Masato (20 January 2010). "The Globular Cluster System of the Virgo Giant Elliptical Galaxy NGC 4636. I. Subaru/Faint Object Camera and Spectrograph Spectroscopy and Database". The Astrophysical Journal. 709 (1): 377–385. arXiv: 0912.0340 . Bibcode:2010ApJ...709..377P. doi:10.1088/0004-637X/709/1/377. S2CID   119238390.
  22. ↑ Lee, Myung Gyoon; Park, Hong Soo; Hwang, Ho Seong; Arimoto, Nobuo; Tamura, Naoyuki; Onodera, Masato (1 February 2010). "The Globular Cluster System of the Virgo Giant Elliptical Galaxy NGC 4636. Ii. Kinematics of the Globular Cluster System". The Astrophysical Journal. 709 (2): 1083–1099. arXiv: 0912.1728 . Bibcode:2010ApJ...709.1083L. doi:10.1088/0004-637X/709/2/1083. S2CID   118547886.
  23. ↑ Schuberth, Y.; Richtler, T.; Hilker, M.; Salinas, R.; Dirsch, B.; Larsen, S. S. (9 August 2012). "Dynamics of the NGC 4636 globular cluster system". Astronomy & Astrophysics. 544: A115. arXiv: 1205.2093 . doi: 10.1051/0004-6361/201015038 .
  24. ↑ Forman, W.; Jones, C.; Tucker, W. (June 1985). "Hot coronae around early-type galaxies". The Astrophysical Journal. 293: 102. Bibcode:1985ApJ...293..102F. doi: 10.1086/163218 . S2CID   122426629.
  25. ↑ Loewenstein, M.; Mushotzky, R. (July 2003). "The nature of dark matter in elliptical galaxies: Chandra observations of NGC 4636". Nuclear Physics B - Proceedings Supplements. 124: 91–94. arXiv: astro-ph/0205359 . Bibcode:2003NuPhS.124...91L. doi:10.1016/S0920-5632(03)02085-1. S2CID   14616681.
  26. ↑ Jones, C.; Forman, W.; Vikhlinin, A.; Markevitch, M.; David, L.; Warmflash, A.; Murray, S.; Nulsen, P. E. J. (10 March 2002). "Chandra Observations of NGC 4636—an Elliptical Galaxy in Turmoil". The Astrophysical Journal. 567 (2): L115–L118. arXiv: astro-ph/0108114 . Bibcode:2002ApJ...567L.115J. doi:10.1086/340114. S2CID   119463742.
  27. 1 2 Baldi, A.; Forman, W.; Jones, C.; Kraft, R.; Nulsen, P.; Churazov, E.; David, L.; Giacintucci, S. (20 December 2009). "The Unusual X-Ray Morphology of NGC 4636 Revealed by Deep Chandra Observations: Cavities and Shocks Created by Past Active Galactic Nucleus Outbursts". The Astrophysical Journal. 707 (2): 1034–1043. arXiv: 0904.2569 . Bibcode:2009ApJ...707.1034B. doi:10.1088/0004-637X/707/2/1034. S2CID   119193902.
  28. ↑ Giacintucci, Simona; O'Sullivan, Ewan; Vrtilek, Jan; David, Laurence P.; Raychaudhury, Somak; Venturi, Tiziana; Athreya, Ramana M.; Clarke, Tracy E.; Murgia, Matteo; Mazzotta, Pasquale; Gitti, Myriam; Ponman, Trevor; Ishwara-Chandra, C. H.; Jones, Christine; Forman, William R. (10 May 2011). "A combined low-radio frequency/X-ray study of galaxy groups I. Giant Metrewave Radio Telescope observations at 235 MHz and 610 MHz". The Astrophysical Journal. 732 (2): 95. arXiv: 1103.1364 . Bibcode:2011ApJ...732...95G. doi:10.1088/0004-637X/732/2/95. S2CID   118449592.
  29. ↑ Allen, S. W.; Dunn, R. J. H.; Fabian, A. C.; Taylor, G. B.; Reynolds, C. S. (11 October 2006). "The relation between accretion rate and jet power in X-ray luminous elliptical galaxies". Monthly Notices of the Royal Astronomical Society. 372 (1): 21–30. arXiv: astro-ph/0602549 . Bibcode:2006MNRAS.372...21A. doi:10.1111/j.1365-2966.2006.10778.x. S2CID   15313083.
  30. ↑ Posson-Brown, Jennifer; Raychaudhury, Somak; Forman, William; Donnelly, R. Hank; Jones, Christine (20 April 2009). "Chandra Observations of the X-Ray Point Source Population in NGC 4636". The Astrophysical Journal. 695 (2): 1094–1110. arXiv: astro-ph/0605308 . Bibcode:2009ApJ...695.1094P. doi:10.1088/0004-637X/695/2/1094. S2CID   119360202.
  31. ↑ Kowal, C. T. (December 1968). "Absolute magnitudes of supernovae". The Astronomical Journal. 73: 1021. Bibcode:1968AJ.....73.1021K. doi: 10.1086/110763 .
  32. ↑ List of Supernovae IAU Central Bureau for Astronomical Telegrams. Retrieved 29 December 2015.
  33. ↑ Hoffleit, Dorrit (1 March 1939). "SN NGC 1003 and Other Supernovae". Harvard College Observatory Bulletin. 910: 1–11. Bibcode:1939BHarO.910....1H. ISSN   0891-3943.
  34. ↑ "Supernova 2020ue in NGC 4636". www.rochesterastronomy.org. Retrieved 2020-01-30.
  35. ↑ Makarov, Dmitry; Karachentsev, Igor (21 April 2011). "Galaxy groups and clouds in the local (z~ 0.01) Universe". Monthly Notices of the Royal Astronomical Society. 412 (4): 2498–2520. arXiv: 1011.6277 . Bibcode:2011MNRAS.412.2498M. doi:10.1111/j.1365-2966.2010.18071.x. S2CID   119194025. Archived from the original on 31 January 2016. Retrieved 9 January 2019.
  36. ↑ "The Virgo II Groups". www.atlasoftheuniverse.com. Retrieved 7 January 2019.


This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.