XMM-Newton

XMM-Newton, also known as the High Throughput X-ray Spectroscopy Mission and the X-ray Multi-Mirror Mission, is an X-ray space observatory launched by the European Space Agency in December 1999 on an Ariane 5 rocket. It is the second cornerstone mission of ESA's Horizon 2000 programme. Named after physicist and astronomer Sir Isaac Newton, the spacecraft is tasked with investigating interstellar X-ray sources, performing narrow- and broad-range spectroscopy, and performing the first simultaneous imaging of objects in both X-ray and optical (visible and ultraviolet) wavelengths.[6]

XMM-Newton
Artist's impression of the XMM-Newton spacecraft
NamesHigh Throughput X-ray Spectroscopy Mission
X-ray Multi-Mirror Mission
Mission typeX-ray astronomy
OperatorEuropean Space Agency
COSPAR ID1999-066A
SATCAT no.25989
Websitehttp://sci.esa.int/xmm-newton/
http://xmm.esac.esa.int/
Mission durationPlanned: 10 years[1]
Elapsed: 21 years, 1 month, 29 days
Spacecraft properties
ManufacturerDornier Satellitensysteme, Carl Zeiss, Media Lario, Matra Marconi Space, BPD Difesa e Spazio, Fokker Space[2]
Launch mass3,764 kg (8,298 lb)[2]
Dry mass3,234 kg (7,130 lb)
DimensionsLength: 10.8 m (35 ft)[2]
Span: 16.16 m (53 ft)[2]
Power1,600 watts[2]
Start of mission
Launch date10 December 1999, 14:32 (1999-12-10UTC14:32) UTC[3]
RocketAriane 5G No. 504[4]
Launch siteGuiana Space Centre ELA-3[2][4]
ContractorArianespace
Entered service1 July 2000[2]
Orbital parameters
Reference systemGeocentric
Semi-major axis65,648.3 km (40,792.0 mi)
Eccentricity0.816585
Perigee altitude5,662.7 km (3,518.6 mi)
Apogee altitude112,877.6 km (70,138.9 mi)
Inclination67.1338 degrees
Period2789.9 minutes
Epoch4 February 2016, 01:06:30 UTC[5]
Main telescope
Type3 × Wolter type-1[2]
DiameterOuter mirror: 70 cm (28 in)[2]
Inner mirror: 30.6 cm (12 in)[2]
Focal length7.5 m (25 ft)[2]
Collecting area0.4425 m2 (5 sq ft) at 1.5 keV[2]
0.1740 m2 (2 sq ft) at 8 keV[2]
Wavelengths0.1-12 keV (12-0.1 nm)[2]
Resolution5 to 14 arcseconds[2]

ESA astrophysics insignia for XMM-Newton
 
Animation of XMM-Newton's trajectory around Earth

Initially funded for two years, with a ten year design life, the spacecraft remains in good health and has received repeated mission extensions, most recently in November 2018 and is scheduled to operate until the end of 2020. It will probably receive a mission extension lasting until 2022.[7] ESA plans to succeed XMM-Newton with the Advanced Telescope for High Energy Astrophysics (ATHENA), the second large mission in the Cosmic Vision 2015–2025 plan, to be launched in 2028.[8] XMM-Newton is similar to NASA's Chandra X-ray Observatory, also launched in 1999.

As of May 2018, close to 5,600 papers have been published about either XMM-Newton or the scientific results it has returned.[9]

Concept and mission history

The observational scope of XMM-Newton includes the detection of X-ray emissions from astronomical objects, detailed studies of star-forming regions, investigation of the formation and evolution of galaxy clusters, the environment of supermassive black holes and mapping of the mysterious dark matter.[10]

In 1982, even before the launch of XMM-Newton's predecessor EXOSAT in 1983, a proposal was generated for a "multi-mirror" X-ray telescope mission.[11][12] The XMM mission was formally proposed to the ESA Science Programme Committee in 1984 and gained approval from the Agency's Council of Ministers in January 1985.[13] That same year, several working groups were established to determine the feasibility of such a mission,[11] and mission objectives were presented at a workshop in Denmark in June 1985.[12][14] At this workshop, it was proposed that the spacecraft contain 12 low-energy and 7 high-energy X-ray telescopes.[14][15] The spacecraft's overall configuration was developed by February 1987, and drew heavily from lessons learned during the EXOSAT mission;[11] the Telescope Working Group had reduced the number of X-ray telescopes to seven standardised units.[14][15] In June 1988 the European Space Agency approved the mission and issued a call for investigation proposals (an "announcement of opportunity").[11][15] Improvements in technology further reduced the number of X-ray telescopes needed to just three.[15]

In June 1989, the mission's instruments had been selected and work began on spacecraft hardware.[11][15] A project team was formed in January 1993 and based at the European Space Research and Technology Centre (ESTEC) in Noordwijk, Netherlands.[13] Prime contractor Dornier Satellitensysteme (a subsidiary of the former DaimlerChrysler Aerospace) was chosen in October 1994 after the mission was approved into the implementation phase, with development and construction beginning in March 1996 and March 1997, respectively.[13][14] The XMM Survey Science Centre was established at the University of Leicester in 1995.[11][16] The three flight mirror modules for the X-ray telescopes were delivered by Italian subcontractor Media Lario in December 1998,[14] and spacecraft integration and testing was completed in September 1999.[13]

XMM left the ESTEC integration facility on 9 September 1999, taken by road to Katwijk then by the barge Emeli to Rotterdam. On 12 September, the spacecraft left Rotterdam for French Guiana aboard Arianespace's transport ship MN Toucan.[17] The Toucan docked at the French Guianese town of Kourou on 23 September, and was transported to Guiana Space Centre's Ariane 5 Final Assembly Building for final launch preparation.[18]

Launch of XMM took place on 10 December 1999 at 14:32 UTC from the Guiana Space Centre.[19] XMM was lofted into space aboard an Ariane 504 rocket, and placed into a highly elliptical, 40-degree orbit that had a perigee of 838 km (521 mi) and an apogee of 112,473 km (69,887 mi).[2] Forty minutes after being released from the Ariane upper stage, telemetry confirmed to ground stations that the spacecraft's solar arrays had successfully deployed. Engineers waited an additional 22 hours before commanding the on-board propulsion systems to fire a total of five times, which, between 10–16 December, changed the orbit to 7,365 × 113,774 km (4,576 × 70,696 mi) with a 38.9-degree inclination. This resulted in the spacecraft making one complete revolution of the Earth approximately every 48 hours.[2][20]

Immediately after launch, XMM began its Launch and Early Orbit phase of operations.[21] On 17 and 18 December 1999, the X-ray modules and Optical Monitor doors were opened, respectively.[22] Instrument activation started on 4 January 2000,[2] and the Instrument Commissioning phase began on 16 January.[23] The Optical Monitor (OM) attained first light on 5 January, the two European Photon Imaging Camera (EPIC) MOS-CCDs followed on 16 January and the EPIC pn-CCD on 22 January, and the Reflection Grating Spectrometers (RGS) saw first light on 2 February.[23] On 3 March, the Calibration and Performance Validation phase began,[2] and routine science operations began on 1 June.[23]

During a press conference on 9 February 2000, ESA presented the first images taken by XMM and announced that a new name had been chosen for the spacecraft. Whereas the program had formally been known as the High Throughput X-ray Spectroscopy Mission, the new name would reflect the nature of the program and the originator of the field of spectroscopy. Explaining the new name of XMM-Newton, Roger Bonnet, ESA's former Director of Science, said, "We have chosen this name because Sir Isaac Newton was the man who invented spectroscopy and XMM is a spectroscopy mission." He noted that because Newton is synonymous with gravity and one of the goals of the satellite was to locate large numbers of black hole candidates, "there was no better choice than XMM-Newton for the name of this mission."[24]

Including all construction, spacecraft launch, and two years of operation, the project was accomplished within a budget of €689 million (1999 conditions).[13][14]

Operation

The spacecraft has the ability to lower the operating temperature of both the EPIC and RGS cameras, a function that was included to counteract the deleterious effects of ionising radiation on the camera pixels. In general, the instruments are cooled to reduce the amount of dark current within the devices. During the night of 3–4 November 2002, RGS-2 was cooled from its initial temperature of −80 °C (−112 °F) down to −113 °C (−171 °F), and a few hours later to −115 °C (−175 °F). After analysing the results, it was determined the optimal temperature for both RGS units would be −110 °C (−166 °F), and during 13–14 November, both RGS-1 and RGS-2 were set to this level. During 6–7 November, the EPIC MOS-CCD detectors were cooled from their initial operating temperature of −100 °C (−148 °F) to a new setting of −120 °C (−184 °F). After these adjustments, both the EPIC and RGS cameras showed dramatic improvements in quality.[25]

On 18 October 2008, XMM-Newton suffered an unexpected communications failure, during which time there was no contact with the spacecraft. While some concern was expressed that the vehicle may have suffered a catastrophic event, photographs taken by amateur astronomers at the Starkenburg Observatory in Germany and at other locations worldwide showed that the spacecraft was intact and appeared on course. A weak signal was finally detected using a 35-metre (115 ft) antenna in New Norcia, Western Australia, and communication with XMM-Newton suggested that the spacecraft's Radio Frequency switch had failed. After troubleshooting a solution, ground controllers used NASA's 34 m (112 ft) antenna at the Goldstone Deep Space Communications Complex to send a command that changed the switch to its last working position. ESA stated in a press release that on 22 October, a ground station at the European Space Astronomy Centre (ESAC) made contact with the satellite, confirming the process had worked and that the satellite was back under control.[26][27][28]

Mission extensions

Because of the spacecraft's good health and the significant returns of data, XMM-Newton has received several mission extensions by ESA's Science Programme Committee. The first extension came during November 2003 and extended operations through March 2008.[29] The second extension was approved in December 2005, extending work through March 2010.[30] A third extension was passed in November 2007, which provided for operations through 2012. As part of the approval, it was noted that the satellite had enough on-board consumables (fuel, power and mechanical health) to theoretically continue operations past 2017.[31] The fourth extension in November 2010 approved operations through 2014.[32] A fifth extension was approved in November 2014, continuing operations through 2018.[33]

Spacecraft
Mock-up of XMM-Newton at the Cité de l'espace, Toulouse.

XMM-Newton is a 10.8-metre (35 ft) long space telescope, and is 16.16 m (53 ft) wide with solar arrays deployed. At launch it weighed 3,764 kilograms (8,298 lb).[2] The spacecraft has three degrees of stabilisation, which allow it to aim at a target with an accuracy of 0.25 to 1 arcseconds. This stabilisation is achieved through the use of the spacecraft's Attitude & Orbit Control Subsystem. These systems also allow the spacecraft to point at different celestial targets, and can turn the craft at a maximum of 90 degrees per hour.[11][24] The instruments on board XMM-Newton are three European Photon Imaging Cameras (EPIC), two Reflection Grating Spectrometers (RGS), and an Optical Monitor.

The spacecraft is roughly cylindrical in shape, and has four major components. At the fore of the spacecraft is the Mirror Support Platform, which supports the X-ray telescope assemblies and grating systems, the Optical Monitor, and two star trackers. Surrounding this component is the Service Module, which carries various spacecraft support systems: computer and electric busses, consumables (such as fuel and coolant), solar arrays, the Telescope Sun Shield, and two S-band antennas. Behind these units is the Telescope Tube, a 6.8-metre (22 ft) long, hollow carbon fibre structure which provides exact spacing between the mirrors and their detection equipment. This section also hosts outgassing equipment on its exterior, which helps remove any contaminants from the interior of the satellite. At the aft end of spacecraft is the Focal Plane Assembly, which supports the Focal Plane Platform (carrying the cameras and spectrometers) and the data-handling, power distribution, and radiator assemblies.[34]

Instruments

European Photon Imaging Cameras

The three European Photon Imaging Cameras (EPIC) are the primary instruments aboard XMM-Newton. The system is composed of two MOS-CCD cameras and a single pn-CCD camera, with a total field of view of 30 arcminutes and an energy sensitivity range between 0.15 and 15 keV (82.7 to 0.83 ångströms). Each camera contains a six-position filter wheel, with three types of X-ray-transparent filters, a fully open and a fully closed position; each also contains a radioactive source used for internal calibration. The cameras can be independently operated in a variety of modes, depending on the image sensitivity and speed needed, as well as the intensity of the target.[35][36][37]

The two MOS-CCD cameras are used to detect low-energy X-rays. Each camera is composed of seven silicon chips (one in the centre and six circling it), with each chip containing a matrix of 600 × 600 pixels, giving the camera a total resolution of about 2.5 megapixels. As discussed above, each camera has a large adjacent radiator which cools the instrument to an operating temperature of −120 °C (−184 °F). They were developed and built by the University of Leicester Space Research Centre and EEV Ltd.[25][35][37]

The pn-CCD camera is used to detect high-energy X-rays, and is composed of a single silicon chip with twelve individual embedded CCDs. Each CCD is 64 × 189 pixels, for a total capacity of 145,000 pixels. At the time of its construction, the pn-CCD camera on XMM-Newton was the largest such device ever made, with a sensitive area of 36 cm2 (5.6 sq in). A radiator cools the camera to −90 °C (−130 °F). This system was made by the Astronomisches Institut Tübingen, the Max Planck Institute for Extraterrestrial Physics, and PNSensor, all of Germany.[35][38][39]

The EPIC system records three types of data about every X-ray that is detected by its CCD cameras. The time that the X-ray arrives allows scientists to develop light curves, which projects the number of X-rays that arrive over time and shows changes in the brightness of the target. Where the X-ray hits the camera allows for a visible image to be developed of the target. The amount of energy carried by the X-ray can also be detected and helps scientists to determine the physical processes occurring at the target, such as its temperature, its chemical make-up, and what the environment is like between the target and the telescope.[40]

Reflection Grating Spectrometers

The Reflection Grating Spectrometers (RGS) are a secondary system on the spacecraft and are composed of two Focal Plane Cameras and their associated Reflection Grating Arrays. This system is used to build X-ray spectral data and can determine the elements present in the target, as well as the temperature, quantity and other characteristics of those elements. The RGS system operates in the 2.5 to 0.35 keV (5 to 35 ångström) range, which allows detection of carbon, nitrogen, oxygen, neon, magnesium, silicon and iron.[41][42]

The Focal Plane Cameras each consist of nine MOS-CCD devices mounted in a row and following a curve called a Rowland circle. Each CCD contains 384 × 1024 pixels, for a total resolution of more than 3.5 megapixels. The total width and length of the CCD array was dictated by the size of the RGS spectrum and the wavelength range, respectively. Each CCD array is surrounded by a relatively massive wall, providing heat conduction and radiation shielding. Two-stage radiators cool the cameras to an operating temperature of −110 °C (−166 °F). The camera systems were a joint effort between SRON, the Paul Scherrer Institute, and MSSL, with EEV Ltd and Contraves Space providing hardware.[25][41][42][43][44]

The Reflection Grating Arrays are attached to two of the primary telescopes. They allow approximately 50% of the incoming X-rays to pass unperturbed to the EPIC system, while redirecting the other 50% onto the Focal Plane Cameras. Each RGA was designed to contain 182 identical gratings, though a fabrication error left one with only 181. Because the telescope mirrors have already focused the X-rays to converge at the focal point, each grating has the same angle of incidence, and as with the Focal Plane Cameras, each grating array conforms to a Rowland circle. This configuration minimises focal aberrations. Each 10 × 20 cm (4 × 8 in) grating is composed of 1 mm (0.039 in) thick silicon carbide substrate covered with a 2,000-ångström (7.9×10−6 in) gold film, and is supported by five beryllium stiffeners. The gratings contain a large number of grooves, which actually perform the X-ray deflection; each grating contains an average of 646 grooves per millimetre. The RGAs were built by Columbia University.[41][42]

Optical Monitor

The Optical Monitor (OM) is a 30 cm (12 in) Ritchey–Chrétien optical/ultraviolet telescope designed to provide simultaneous observations alongside the spacecraft's X-ray instruments. The OM is sensitive between 170 and 650 nanometres in a 17 × 17 arcminute square field of view co-aligned with the centre of the X-ray telescope's field of view. It has a focal length of 3.8 m (12 ft) and a focal ratio of ƒ/12.7.[45][46]

The instrument is composed of the Telescope Module, containing the optics, detectors, processing equipment, and power supply; and the Digital Electronics Module, containing the instrument control unit and data processing units. Incoming light is directed into one of two fully redundant detector systems. The light passes through an 11-position filter wheel (one opaque to block light, six broad band filters, one white light filter, one magnifier, and two grisms), then through an intensifier which amplifies the light by one million times, then onto the CCD sensor. The CCD is 384 × 288 pixels in size, of which 256 × 256 pixels are used for observations; each pixel is further subsampled into 8 × 8 pixels, resulting in a final product that is 2048 × 2048 in size. The Optical Monitor was built by the Mullard Space Science Laboratory with contributions from organisations in the United States and Belgium.[45][46]

Telescopes
Focusing X-rays with glancing reflection in a Wolter Type-1 optical system

Feeding the EPIC and RGS systems are three telescopes designed specifically to direct X-rays into the spacecraft's primary instruments. The telescope assemblies each have a diameter of 90 cm (35 in), are 250 cm (98 in) in length, and have a base weight of 425 kg (937 lb). The two telescopes with Reflection Grating Arrays weigh an additional 20 kg (44 lb). Components of the telescopes include (from front to rear) the mirror assembly door, entrance and X-ray baffles, mirror module, electron deflector, a Reflection Grating Array in two of the assemblies, and exit baffle.[13][47][48][49]

Each telescope consists of 58 cylindrical, nested Wolter Type-1 mirrors developed by Media Lario of Italy, each 600 mm (24 in) long and ranging in diameter from 306 to 700 mm (12.0 to 27.6 in), producing a total collecting area of 4,425 cm2 (686 sq in) at 1.5 keV and 1,740 cm2 (270 sq in) at 8 keV.[2] The mirrors range from 0.47 mm (0.02 in) thick for the innermost mirror to 1.07 mm (0.04 in) thick for the outermost mirror, and the separation between each mirror ranges from 1.5 to 4 mm (0.06 to 0.16 in) from innermost to outermost.[2] Each mirror was built by vapour-depositing a 250 nm layer of gold reflecting surface onto a highly polished aluminium mandrel, followed by electroforming a monolithic nickel support layer onto the gold. The finished mirrors were glued into the grooves of an Inconel spider, which keeps them aligned to within the five-micron tolerance required to achieve adequate X-ray resolution. The mandrels were manufactured by Carl Zeiss AG, and the electroforming and final assembly were performed by Media Lario with contributions from Kayser-Threde.[50]

Subsystems

Attitude & Orbit Control System

Spacecraft three-axis attitude control is handled by the Attitude & Orbit Control System (AOCS), composed of four reaction wheels, four inertial measurement units, two star trackers, three fine Sun sensors, and three Sun acquisition sensors. The AOCS was provided by Matra Marconi Space of the United Kingdom.[2][51][52]

Coarse spacecraft orientation and orbit maintenance is provided by two sets of four 20-newton (4.5 lbf) hydrazine thrusters (primary and backup).[2] The hydrazine thrusters were built by DASA-RI of Germany.[53]

The AOCS was upgraded in 2013 with a software patch ('4WD'), to control attitude using the 3 prime reaction wheels plus the 4th, spare wheel, unused since launch, with the aim of saving propellant to extend the spacecraft lifetime.[54][55] In 2019 the fuel was predicted to last until 2030.[56]

Power systems

Primary power for XMM-Newton is provided by two fixed solar arrays. The arrays are composed of six panels measuring 1.81 × 1.94 m (5.9 × 6.4 ft) for a total of 21 m2 (230 sq ft) and a mass of 80 kg (180 lb). At launch, the arrays provided 2,200 W of power, and were expected to provide 1,600 W after ten years of operation. Deployment of each array took four minutes. The arrays were provided by Fokker Space of the Netherlands.[2][57]

When direct sunlight is unavailable, power is provided by two nickel–cadmium batteries providing 24 A·h and weighing 41 kg (90 lb) each. The batteries were provided by SAFT of France.[2][57]

Radiation Monitor System

The cameras are accompanied by the EPIC Radiation Monitor System (ERMS), which measures the radiation environment surrounding the spacecraft; specifically, the ambient proton and electron flux. This provides warning of damaging radiation events to allow for automatic shut-down of the sensitive camera CCDs and associated electronics. The ERMS was built by the Centre d'Etude Spatiale des Rayonnements of France.[13][35][37]

Visual Monitoring Cameras

The Visual Monitoring Cameras (VMC) on the spacecraft were added to monitor the deployment of solar arrays and the sun shield, and have additionally provided images of the thrusters firing and outgassing of the Telescope Tube during early operations. Two VMCs were installed on the Focal Plane Assembly looking forward. The first is FUGA-15, a black and white camera with high dynamic range and 290 × 290 pixel resolution. The second is IRIS-1, a colour camera with a variable exposure time and 400 × 310 pixel resolution. Both cameras measure 6 × 6 × 10 cm (2.4 × 2.4 × 3.9 in) and weight 430 g (15 oz). They use active pixel sensors, a technology that was new at the time of XMM-Newton's development. The cameras were developed by OIC–Delft and IMEC, both of Belgium.[53][58]

Ground systems

XMM-Newton mission control is located at the European Space Operations Centre (ESOC) in Darmstadt, Germany. Two ground stations, located in Perth and Kourou, are used to maintain continuous contact with the spacecraft through most of its orbit. Back-up ground stations are located in Villafranca del Castillo, Santiago, and Dongara. Because XMM-Newton contains no on-board data storage, science data is transmitted to these ground stations in real time.[20]

Data is then forwarded to the European Space Astronomy Centre's Science Operations Centre in Villafranca del Castillo, Spain, where pipeline processing has been performed since March 2012. Data is archived at the ESAC Science Data Centre,[59] and distributed to mirror archives at the Goddard Space Flight Center and the XMM-Newton Survey Science Centre (SSC) at the L'Institut de Recherche en Astrophysique et Planétologie. Prior to June 2013, the SSC was operated by the University of Leicester, but operations were transferred due to a withdrawal of funding by the United Kingdom.[16][60]

Observations and discoveries

The space observatory was used to discover the galaxy cluster XMMXCS 2215-1738, 10 billion light years away from Earth.[61]

The object SCP 06F6, discovered by the Hubble Space Telescope (HST) in February 2006, was observed by XMM-Newton in early August 2006 and appeared to show an X-ray glow around it[62] two orders of magnitude more luminous than that of supernovae.[63]

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 a smaller companion neutron star with accompanying X-ray emissions.[64][65]

In February 2013 it was announced that XMM-Newton along with NuSTAR have for the first time measured the spin rate of a supermassive black hole, by observing the black hole at the core of galaxy NGC 1365. At the same time, it verified the model that explains the distortion of X-rays emitted from a black hole.[66][67]

In February 2014, separate analyses extracted from the spectrum of X-ray emissions observed by XMM-Newton a monochromatic signal around 3.5 keV.[68][69] This signal is coming from different galaxy clusters, and several scenarios of dark matter can justify such a line. For example, a 3.5 keV candidate annihilating into 2 photons,[70] or a 7 keV dark matter particle decaying into photon and neutrino.[71]

See also

References
  1. "XMM-Newton factsheet". European Space Agency. 20 August 2014. Retrieved 16 June 2018.
  2. Wilson, Andrew (June 2005). "XMM-Newton" (PDF). ESA Achievements (3rd ed.). European Space Agency. pp. 206–209. ISBN 92-9092-493-4. ESA Publication BR-250.
  3. "A Faultless Launch". European Space Agency. 10 December 1999. Retrieved 21 September 2014.
  4. "Ariane-5". Gunter's Space Page. Retrieved 21 September 2014.
  5. "XMM - Orbit". Heavens Above. 3 February 2016. Retrieved 3 February 2016.
  6. "XMM-Newton: Objectives". European Space Agency. 8 July 2011. Retrieved 5 February 2016.
  7. "Extended life for ESA's science missions". ESA. Retrieved 14 November 2018.
  8. Bauer, Markus (27 June 2014). "Athena to study the hot and energetic Universe". European Space Agency. Retrieved 8 June 2017.
  9. Kretschmar, Peter (2018). XMM-Newton Overall Mission Status (PDF). XMM-Newton Users' Group Meeting #19. 17-18 May 2018. Villafranca del Castillo, Spain.
  10. Schartel, Norbert; Santos-Lleo, María; Parmar, Arvind; Clavel, Jean (February 2010). "10 years of discovery: Commemorating XMM-Newton's first decade". ESA Bulletin (141): 2–9. ISSN 0376-4265.
  11. "XMM-Newton overview". European Space Agency. 4 June 2013. Retrieved 31 January 2016.
  12. Jansen, F.; Lumb, D.; Altieri, B.; Clavel, J.; Ehle, M.; et al. (2001). "XMM-Newton observatory. I. The spacecraft and operations" (PDF). Astronomy and Astrophysics. 365 (1): L1–L6. Bibcode:2001A&A...365L...1J. doi:10.1051/0004-6361:20000036.
  13. "Universe X-rayed and British science honoured". Aircraft Engineering and Aerospace Technology. Emerald Group. 72 (4). 2000. doi:10.1108/aeat.2000.12772daf.010.
  14. Lumb, David H.; Schartel, Norbert; Jansen, Fred A. (February 2012). "X-ray Multi-mirror Mission (XMM-Newton) observatory". Optical Engineering. 51 (1). 011009. arXiv:1202.1651. Bibcode:2012OptEn..51a1009L. doi:10.1117/1.OE.51.1.011009. S2CID 119237088.
  15. La Palombara, Nicola (12 September 2010). "Twenty years with XMM (and even more...)" (PDF). Istituto Nazionale di Astrofisica. Retrieved 31 January 2016.
  16. "XMM-Newton Survey Science Centre". University of Leicester. Retrieved 31 January 2016.
  17. "'Black Beauty' sails to the tropics". European Space Agency. 13 September 1999. Retrieved 3 February 2016.
  18. "XMM arrives in French Guiana". European Space Agency. 27 September 1999. Retrieved 3 February 2016.
  19. "XMM-Newton: Trajectory Details". National Space Science Data Center. NASA. Retrieved 1 February 2016.
  20. "XMM-Newton: Orbit/Navigation". European Space Agency. 19 September 2011. Retrieved 2 February 2016.
  21. "XMM-Newton Operations". European Space Agency. Retrieved 3 February 2016.
  22. "PR 54-1999: XMM flying beautifully" (Press release). European Space Agency. 20 December 1999. PR 54-1999. Retrieved 3 February 2016.
  23. "XMM-Newton What's New". NASA. Retrieved 3 February 2016.
  24. "XMM-Newton: Fact Sheet". European Space Agency. 21 December 2012. Retrieved 3 February 2016.
  25. "First results from XMM-Newton RGS and EPIC MOS instruments cooling". European Space Agency. 11 November 2002. Retrieved 5 February 2016.
  26. "ESA Receives An Orbital Call For Help". Aero-News.net. 23 October 2008. Retrieved 5 February 2016.
  27. "Re-establishing contact with XMM-Newton". European Space Agency. 22 October 2008. Retrieved 5 February 2016.
  28. "XMM-Newton talks again loud and clear". European Space Agency. 23 October 2008. Retrieved 5 February 2016.
  29. "XMM-Newton-NEWS #36". European Space Agency. 1 December 2003. Retrieved 4 February 2016.
  30. "XMM-Newton Mission Extension Approved". European Space Agency. 6 December 2005. Retrieved 4 February 2016.
  31. "XMM-Newton Mission Extension Approved". European Space Agency. 15 November 2007. Retrieved 4 February 2016.
  32. "Europe maintains its presence on the final frontier". European Space Agency. 22 November 2010. Retrieved 5 February 2016.
  33. "Working life extensions for ESA's science missions". European Space Agency. 20 November 2014. Retrieved 5 February 2016.
  34. Barré, H.; Nye, H.; Janin, G. (December 1999). "An Overview of the XMM Observatory System". Bulletin. European Space Agency. 100 (100): 15–20. Bibcode:1999ESABu.100...15B. ISSN 0376-4265.
  35. "XMM-Newton: Instruments: European Photon Imaging Camera (EPIC)". European Space Agency. 18 August 2015. Retrieved 6 February 2016.
  36. "Science modes of the EPIC cameras". XMM-Newton Users' Handbook. European Space Agency. 20 July 2015. p. 3.3.2. Issue 2.13. Retrieved 6 February 2016.
  37. Turner, M. J. L.; Abbey, A.; Arnaud, M.; Balasini, M.; Barbera, M.; et al. (January 2001). "The European Photon Imaging Camera on XMM-Newton: The MOS cameras" (PDF). Astronomy and Astrophysics. 365 (1): L27–L35. arXiv:astro-ph/0011498. Bibcode:2001A&A...365L..27T. doi:10.1051/0004-6361:20000087. S2CID 17323951.
  38. "Detector Concept of pn-CCDs". PNSensor.de. 2 July 2008. Retrieved 6 February 2016.
  39. Strüder, L.; Briel, U.; Dennerl, K.; Hartmann, R.; Kendziorra, E.; et al. (January 2001). "The European Photon Imaging Camera on XMM-Newton: The pn-CCD camera" (PDF). Astronomy and Astrophysics. 365 (1): L18–L26. Bibcode:2001A&A...365L..18S. doi:10.1051/0004-6361:20000066.
  40. Baskill, Darren (14 September 2006). "The EPIC-MOS instruments on-board XMM-Newton". University of Leicester. Archived from the original on 1 July 2007.
  41. den Herder, J. W.; Brinkman, A. C.; Kahn, S. M.; Branduardi-Raymont, G.; Thomsen, K.; et al. (January 2001). "The Reflection Grating Spectrometer on board XMM-Newton" (PDF). Astronomy and Astrophysics. 365 (1): L7–L17. Bibcode:2001A&A...365L...7D. doi:10.1051/0004-6361:20000058. den Herder (2001) states that the RGS system operates in the 6 to 38 ångström range, but the majority of sources, including official ESA websites, contradict this.
  42. Brinkman, A.; Aarts, H.; den Boggende, A.; Bootsma, T.; Dubbeldam, L.; et al. (1998). The Reflection Grating Spectrometer on board XMM (PDF). Science with XMM. 30 September-2 October 1998. Noordwijk, The Netherlands. Bibcode:1998sxmm.confE...2B.
  43. "The Reflection Grating Spectrometer (RGS) onboard XMM-Newton". European Space Agency. Retrieved 6 February 2016.
  44. "XMM-Newton: Instruments: Reflection Grating Spectrometer (RGS)". European Space Agency. 18 August 2015. Retrieved 6 February 2016.
  45. "XMM-Newton: Instruments: Optical Monitor (OM)". European Space Agency. 18 August 2015. Retrieved 6 February 2016.
  46. Mason, K. O.; Breeveld, A.; Much, R.; Carter, M.; Cordova, F. A.; et al. (January 2001). "The XMM-Newton optical/UV monitor telescope" (PDF). Astronomy and Astrophysics. 365 (1): L36–L44. arXiv:astro-ph/0011216. Bibcode:2001A&A...365L..36M. doi:10.1051/0004-6361:20000044. S2CID 53630714.
  47. "XMM-Newton: X-ray Mirrors: Introduction". European Space Agency. 3 April 2013. Retrieved 5 February 2016.
  48. "XMM-Newton: X-ray Mirrors: Configuration". European Space Agency. 3 April 2013. Retrieved 5 February 2016.
  49. "XMM-Newton: X-ray Mirrors: Optical Design". European Space Agency. 3 April 2013. Retrieved 5 February 2016.
  50. de Chambure, D.; Lainé, R.; van Katwijk, K.; van Casteren, J.; Glaude, P. (February 1997). "Producing the X-Ray Mirrors for ESA's XMM spacecraft". Bulletin. European Space Agency (89): 68–79. ISSN 0376-4265.
  51. "XMM-Newton: Engineering: Attitude and Orbital Control Systems (AOCS)". European Space Agency. 19 September 2011. Retrieved 7 February 2016.
  52. "Attitude & Orbit Control Subsystem (AOCS)". XMM-Newton Users' Handbook. European Space Agency. 20 July 2015. p. 3.6.2. Issue 2.13. Retrieved 6 February 2016.
  53. "Jets in space: XMM unique pictures". European Space Agency. 17 December 1999. Retrieved 12 February 2016.
  54. Speed, Richard. "The ultimate 4-wheel-drive: How ESA's keeping XMM-Newton alive after 20 years and beyond". www.theregister.com. Retrieved 2020-12-31.
  55. Pantaleoni, Mauro. "XMM-Newton's operational challenge of changing the attitude control to 4 active reaction wheels, after 12 years of routine operations". ResearchGate. Retrieved 31 December 2020.
  56. Kirsch, Marcus. "XMM-Newton -MOC preparing for the 3rd decade of operations" (PDF). ESA. Retrieved 31 December 2020.
  57. "XMM spreads its wings for the last time on Earth". European Space Agency. 18 August 1999. Retrieved 12 February 2016.
  58. Habinc, Sandi; Karlsson, Anders; Wijmans, Willem; Jameux, David; Ogiers, Werner; et al. (2000). In-flight Results Using Visual Monitoring Cameras (PDF). Data Systems in Aerospace. 22–26 May 2000. Montreal, Canada. Bibcode:2000ESASP.457...71H.
  59. "Welcome to the XMM-Newton Science Archive". European Space Agency. 6 August 2018. Retrieved 15 October 2018.
  60. "XMM-Newton Survey Science Centre". L'Institut de Recherche en Astrophysique et Planétologie. Retrieved 31 January 2016.
  61. Bealing, Jacqui (7 June 2006). "Massive galaxy cluster found 10 billion light years away" (Press release). University of Sussex.
  62. Brumfiel, Geoff (19 September 2008). "How they wonder what you are". Nature. doi:10.1038/news.2008.1122. Retrieved 12 February 2016.
  63. Gänsicke, Boris T.; Levan, Andrew J.; Marsh, Thomas R.; Wheatley, Peter J. (June 2009). "SCP 06F6: A Carbon-rich Extragalactic Transient at Redshift Z ≃ 0.14?". The Astrophysical Journal Letters. 697 (2): L129–L132. arXiv:0809.2562. Bibcode:2009ApJ...697L.129G. doi:10.1088/0004-637X/697/2/L129. S2CID 14807033.
  64. "Neutron star bites off more than it can chew". European Space Agency. 28 June 2011. Retrieved 12 February 2016.
  65. Bozzo, E.; Giunta, A.; Cusumano, G.; Ferrigno, C.; Walter, R.; et al. (July 2011). "XMM-Newton observations of IGR J18410-0535: the ingestion of a clump by a supergiant fast X-ray transient". Astronomy and Astrophysics. 531. A130. arXiv:1106.5125. Bibcode:2011A&A...531A.130B. doi:10.1051/0004-6361/201116726. S2CID 119231893.
  66. Harrington, J.D.; Clavin, Whitney (27 February 2013). "NASA's NuSTAR Helps Solve Riddle of Black Hole Spin" (Press release). NASA. Retrieved 20 September 2014.
  67. Risaliti, G.; Harrison, F. A.; Madsen, K. K.; Walton, D. J.; Boggs, S. E.; et al. (February 2013). "A rapidly spinning supermassive black hole at the centre of NGC 1365". Nature. 494 (7438): 449–451. arXiv:1302.7002. Bibcode:2013Natur.494..449R. doi:10.1038/nature11938. PMID 23446416. S2CID 2138608.
  68. Bulbul, Esra; Markevitch, Maxim; Foster, Adam; Smith, Randall K.; Loewenstein, Michael; et al. (July 2014). "Detection of an Unidentified Emission Line in the Stacked X-Ray Spectrum of Galaxy Clusters". The Astrophysical Journal. 789 (1). 13. arXiv:1402.2301. Bibcode:2014ApJ...789...13B. doi:10.1088/0004-637X/789/1/13. S2CID 118468448.
  69. Boyarsky, Alexey; Ruchayskiy, Oleg; Iakubovskyi, Dmytro; Franse, Jeroen (December 2014). "Unidentified Line in X-Ray Spectra of the Andromeda Galaxy and Perseus Galaxy Cluster". Physical Review Letters. 113 (25). 251301. arXiv:1402.4119. Bibcode:2014PhRvL.113y1301B. doi:10.1103/PhysRevLett.113.251301. PMID 25554871. S2CID 21406370.
  70. Dudas, Emilian; Heurtier, Lucien; Mambrini, Yann (August 2014). "Generating x-ray lines from annihilating dark matter". Physical Review D. 90 (3). 035002. arXiv:1404.1927. Bibcode:2014PhRvD..90c5002D. doi:10.1103/PhysRevD.90.035002. S2CID 118573978.
  71. Ishida, Hiroyuki; Jeong, Kwang Sik; Takahashi, Fuminobu (May 2014). "7 keV sterile neutrino dark matter from split flavor mechanism". Physics Letters B. 732: 196–200. arXiv:1402.5837. Bibcode:2014PhLB..732..196I. doi:10.1016/j.physletb.2014.03.044. S2CID 119226364.

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