Circinus X-1 Explained

Circinus X-1 is an X-ray binary star system that includes a neutron star. Observation of Circinus X-1 in July 2007 revealed the presence of X-ray jets normally found in black hole systems; it is the first of the sort to be discovered that displays this similarity to black holes. Circinus X-1 may be among the youngest X-ray binaries observed.

Location, distance

On June 14, 1969, an Aerobee 150 rocket, launched from Natal, Rio Grande do Norte, Brazil, obtained X-ray data during a scan of the Norma-Lupus-Circinus region that detected a well-isolated source at ℓ = 321.4±0.9° b = -0.5±2° (galactic), RA Dec within the constellation Circinus and referred to as Circinus XR-1 (Cir XR-1).[1] The distance of Circinus X-1 was not well established, with a low estimate of 13,400 light years[2] and high estimate of 26,000 light years.[3]

On June 23, 2015, an article published on NASA's Chandra X-Ray Observatory's website, revealed that an international team of astronomers has succeeded in determining its distance from Earth with more precision - via a method of triangulation of X-ray light emitted by the star, echoing through stellar clouds and interstellar dust - as being about 30,700 light-years.[4]

X-ray source and age related to supernova remnant

A 16.6 day X-ray period was found by Kaluzienski et al.[5] The X-ray source is assumed to be a neutron star as part of a low-mass X-ray binary (LMXB), type-I X-ray burster.[6] The X-ray and radio nebulae surrounding Circinus X-1 have properties consistent with a young supernova remnant. This rare case of an X-ray binary apparently associated with a supernova remnant suggests the binary is very young on cosmic time scales, possibly less than 4600 years old.[7] An association of Circinus X-1 with a different nearby supernova remnant, G321.9-0.3, has been ruled out.[6]

Other spectral regions

The binary nature of Cir X-1 has been established.[8] The binary's radio component and a possible visual counterpart were identified by Whelan et al.[9] Its infrared counterpart was located and found to flare with a 16.6-day period by Glass.[10] A (heavily reddened) precise optical counterpart (now known as BR Cir) was identified by Moneti.[11]

References

Notes and References

  1. Margon B. Lampton M. Bowyer S. Cruddace R . A Pulsing X-Ray Source in Circinus . Astrophys. J. . Oct 1971 . 169 . 10 . L23–5 . 1971ApJ...169L..23M . 10.1086/180806 . 2060/19710026671 . free .
  2. 4. R. Iaria. M. Spano. T. DiSalvo. N.R. Robba. L. Burderi. R. Fender. M. Van Der Klis. F. Frontera. On The Soft Excess In The X-Ray Spectrum Of Circinus X-1: Revisitation Of The Distance To Circinus X-1. The Astrophysical Journal. January 2005. 619. 1. 503–516. 10.1086/426422. astro-ph/0410259 . 2005ApJ...619..503I . 18973228.
  3. Web site: Circinus X-1: Neutron Stars Join The Black Hole Jet Set. Harvard-Smithsonian Center for Astrophysics. 5 December 2013.
  4. Web site: NASA's Chandra Captures X-Ray Echoes Pinpointing Distant Neutron Star. 23 June 2015 . 2015-06-24.
  5. Kaluzienski, L. J.. Holt, S. S.. Boldt, E. A.. Serlemitsos, P. J.. Evidence for a 16.6 day period from Circinus X-1. Astrophysical Journal. 1976. 208. L71–L75. 1976ApJ...208L..71K . 10.1086/182235 . free.
  6. 10.1051/0004-6361:20020224 . Mignani RP . De Luca A . Caraveo PA . Patrizia A. Caraveo . Mirabel IF . HST observations rule out the association between Cir X-1 and SNR G321.9-0.3 . Astron. Astrophys. . 2002 . 386 . 2 . 487–91 . 2002A&A...386..487M. astro-ph/0202268 . 18606269 .
  7. 4. S. Heinz. P. Sell. R.P. Fender. P.G. Jonker. W.N. Brandt. D.E. Calvelo-Santos. A.K. Tzioumis. M.A. Nowak. N.S. Schulz. R. Wijnands. M. Van Der Klis. The Youngest Known X-ray Binary: Circinus X-1 and its Natal Supernova Remnant. The Astrophysical Journal. December 2013. 779. 2. 10.1088/0004-637X/779/2/171. 1312.0632 . 2013ApJ...779..171H. 171. 6064052.
  8. Jones C. Tananbaum H. Giacconi R . UHURU Observations of the Binary Nature of Circinus X-1 . 141st Meeting Amer Astron Soc . 5. 395. Tucson, Arizona . 1973 . 1973BAAS....5..395J .
  9. 4. Whelan, J. A. J.. Mayo, S. K.. Wickramasinghe, D. T.. Murdin, P. G.. Peterson, B. A.. Hawarden, T. G.. Longmore, A. J.. Haynes, R. F.. Goss, W. M.. Simons, L. W.. Caswell, J. L.. Little, A. G.. McAdam, W. B.. Monthly Notices of the Royal Astronomical Society. 1977. 181. 2. 259–271. 1977MNRAS.181..259W. The optical and radio counterpart of Circinus X-1 /3U 1516-56/ . 10.1093/mnras/181.2.259 . free.
  10. Glass. I.S.. Variations of Circinus X-1 in the infrared. Monthly Notices of the Royal Astronomical Society. 1978. 183. 3. 335–340. 1978MNRAS.183..335G . 10.1093/mnras/183.3.335 . free.
  11. Moneti. A.. Astronomy and Astrophysics. Optical and infrared observations of Circinus X-1. 1992. 260. L7–L10. 1992A&A...260L...7M .

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Circinus X-1".

Except where otherwise indicated, Everything.Explained.Today is © Copyright 2009-2024, A B Cryer, All Rights Reserved. Cookie policy.