XMM-Newton

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XMM-Newton
Cité de l'espace XMM-Newton mock-up
Mock-up of the XMM-Newton at the Cité de l'espace, Toulouse
General information
Organization ESA
Launch date 10 December 1999
Launch site Guiana Space Centre, Kourou, French Guiana, South America
Launch vehicle Ariane 5
Mission length 14 years and 7 months elapsed
Mass 3800 kg
Type of orbit Elliptical
Orbit height 7,000 to 114,000 km
Orbit period 48 hours
Wavelength X-ray
Collecting area 4300 cm² (three mirror-assemblies of 1400 cm² each)
Focal length 7.5 m
Website http://xmm.esac.esa.int
http://xmm.sonoma.edu/

The XMM-Newton (X-ray Multi-Mirror Mission - Newton) is an orbiting X-ray observatory launched by ESA in December 1999 on an Ariane 5 rocket. It is named in honor of Sir Isaac Newton.

Originally known as the High Throughput X-ray Spectroscopy Mission it was placed in a very eccentric 48 hour elliptical orbit at 40°; at its apogee it is nearly 114,000 kilometres (71,000 mi) from Earth, while the perigee is only 7,000 kilometres (4,300 mi)

The satellite weighs 3,800 kilograms (8,400 lb), is 10 metres (33 ft) long and 16 metres (52 ft) in span with its solar arrays deployed. It holds three X-ray telescopes, developed by Media Lario of Italy, each of which contains 58 Wolter-type concentric mirrors. The combined collecting area is 4,300 cm². The three European Photon Imaging Cameras (EPIC) are sensitive over the energy range 0.2 keV to 12 keV. Other instruments onboard are two reflection grating spectrometers which are sensitive below ~2 keV, and a 30 centimetres (12 in) diameter Ritchey-Chretien optical/UV telescope.

The mission was proposed in 1984 and approved in 1985; a project team was formed in 1993 and development work began in 1996. The satellite was constructed and tested from March 1997 to September 1999. Launched in Dec 1999, in-orbit commissioning started Jan 2000, and the first images were published Feb 2000. The original mission lifetime was two years, but it has now been extended for further observations until at least 2010,[1] and again until 2012, and technically the observatory could operate until beyond 2018.[2]

Observations are managed and archived at the European Space Astronomy Centre (formerly known as VILSPA) at Villafranca, Spain. Until March 2012 the scientific data placed into the archive and distributed to observers were processed by the XMM-Newton Survey Science Centre led by the University of Leicester, England. After this date, responsibility for data processing transferred to the Science Operations Centre at ESAC.

The European satellite XMM-Newton (X-ray Multi Mirror), built under contract to ESA by a consortium of 35 European companies with Astrium as prime contractor, by far excels its predecessor, the Astrium-built ROSAT satellite.

Observations and discoveries[edit]

The observational scope of XMM Newton includes the detection of X-ray emissions from Solar System objects, detailed studies of star-forming regions, investigation of the formation and evolution of galaxy clusters, the environment of supermassive black holes and the mapping of the mysterious "dark matter".[3]

It was used to discover the 10 billion light years from Earth galaxy cluster XMMXCS 2215-1738,[4] as well as the 7-billion light year away 2XMM J083026+524133.[5]

The object SCP 06F6, discovered by the Hubble Space Telescope (HST) in February 2006, was then observed by XMM Newton in early August 2006, and appeared to show an X-ray glow around it[6] two orders of magnitude more luminous than that of supernovae.[7]

In June 2011, a team from the University of Geneva, Switzerland, reported XMM-Newton seeing a flare that lasted four hours at a peak intensity of 10,000 times the normal rate, from an observation of Supergiant Fast X-Ray Transient IGR J18410-0535, where a blue supergiant star shed a plume of matter that was partly ingested by the smaller neutron star with the accompanying X-ray emissions.[8]

Even more surprising, in February 2014, different analyses[9][10] have extracted from the spectrum of X-ray emissions observed by XMM-Newton, a monochromatic signal around 3.5 keV. This signal is coming from different galaxy cluster (like Perseus or Centaurus ) and several scenarios of dark matter can justify such a line. We can cite for example a 3.5 keV candidate annihilating into 2 photons,[11] or a 7 keV dark matter particle decaying into photon and neutrino.[12] In any case, it would be a warm dark matter which could be motivated also by other astrophysical observations (core galactic profiles and missing of small structures around the milky way).

Details of the telescopes[edit]

Each telescope consists of 58 600 mm-long shells, with diameters from 306 to 700 millimetres, and thickness linearly dependent on the diameter increasing from 470 µm at the small shells to 1070 µm at the large one; the fully assembled telescope has gaps of about one millimetre between the shells. The shells are made by electroforming onto a highly polished aluminium mandrel, starting with a 250 nm layer of vapour-deposited gold that becomes the reflecting surface, then the nickel support; the mandrels are reusable but a different one is needed for each shell. The electroforming deposits nickel at a rate of 10 µm per hour. The mandrels were manufactured at Carl Zeiss, and the electroforming and final assembly performed at Media Lario; Kayser-Threde also played a role.[13]

The shells are glued into grooves in an Inconel spider, which keeps them aligned to within the five-micron tolerance required to get adequate X-ray resolution.

Scientific results[edit]

In February of XMM-Newton space observatory along with NuSTAR have measured the spin rate of a supermassive black hole located at the core of galaxy NGC 1365.[14]

See also[edit]

References[edit]

  1. ^ "Mission extension to 2010". Dec 2005. 
  2. ^ "Astrium-built XMM-Newton telescope with sensational results on exploding stars, black holes and galaxy clusters". 3 Dec 2009. 
  3. ^ ESA Bulletin 141, February 2010: 10 Years of Discovery - Commemorating XMM Newton's First Decade
  4. ^ http://www.physorg.com/news68820846.html Massive galaxy cluster found 10 billion light years away June 6th, 2006, Space & Earth magazine
  5. ^ ""XMM discovers monster galaxy cluster", DR EMILY BALDWIN, ASTRONOMY NOW, August 27, 2008". Astronomynow.com. 2008-08-27. Retrieved 2013-05-31. 
  6. ^ How they wonder what you are, Nature News, 19 September 2008
  7. ^ Gänsicke et al.: SCP06F6: A carbon-rich extragalactic transient at redshift z~0.14. Preprint, 2008.
  8. ^ Neutron star bites off more than it can chew, spacedaily.com, 29 June 2011
  9. ^ E. Bulbul et al. http://arxiv.org/abs/1402.2301 "Detection of An Unidentified Emission Line in the Stacked X-ray spectrum of Galaxy Clusters"
  10. ^ A. Boyarski et al.: http://arxiv.org/abs/1402.4119, "An unidentified line in X-ray spectra of the Andromeda galaxy and Perseus galaxy cluster"
  11. ^ E. Dudas, L. Heurtier, Y. Mambrini: http://arxiv.org/abs/arXiv:1404.1927, "Generating X-ray lines from annihilating dark matter"
  12. ^ H. Ishida, K.S. Jeong, F. Takahashi : http://arxiv.org/abs/arXiv:1402.5837, "7 keV sterile neutrino dark matter from split flavor mechanism"
  13. ^ "Producing the X-Ray Mirrors for ESA's XMM spacecraft". Esa.int. Retrieved 2013-05-31. 
  14. ^ "NASA's NuSTAR Helps Solve Riddle of Black Hole Spin" (Press release). Whitney Clavin, NASA. 27 February 2013. Retrieved 4 March 2013. 

External links[edit]