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Hot topics and future missions of X-ray Astrophysics Enrico Costa IAPS-INAF, Roma, Italy SpacePart12-4th - CERN 2012/11/5 - E.Costa 50 years ago On september 1949 a NRL team lead by Herb ert Fried man, performed a rockett (V2 ) borne experiment searching for extreme UV and X-rays from outside the atmosphere. This was the first detection of astronomic X-rays. In 1962 a rockett experiment built by R.Giacconi (America Science & Engineering), actuating an idea of Bruno Rossi, discovered the intense diffuse background of X-rays and a very bright source, later named Sco X-1. This was the first detection of non solar Astronomic X-rays. The main lesson from this is: leave a room for discovery. This is also true for costly science. SpacePart12-4th - CERN 2012/11/5 - E.Costa 50 years after the discovery of CR A result from CR scientists. Nobody believed that any non solar X ray could be detected (at least without telescopes). Rossi stated that we must give the Nature the chance to surprize us. The main lesson from this is: leave a room for discovery. This is also true for costly science. SpacePart12-4th - CERN 2012/11/5 - E.Costa In 50 years: 27 past missions ANS - Lifetime: Aug 1974 - June 1977, Energy Range: 0.1 - 30 keV and 1500-3300 Angstoms Ariel V - Lifetime: Oct 1974 - Mar 1980, Energy Range: 0.3 - 40 keV ASCA -First X-rayym mission to com bine im ag ing cap ability with broad p ass band, ,g good sp ectral resolution, and a large effective area. (1993 - 2001) BBXRT - Lifetime: Dec 1990, Energy Range: 0.3 - 12 keV, Shuttle-borne instrument BeppoSAX - Broad band energy. X-ray imaging the sources associated with Gamma-ray bursts and determining their positions with an unprecedented precision. (1996 - 2002) CGRO - Compton Gamma Ray Observatory. First Great Gamma-Ray observatory. Discovery of an isotropic distribution of the Gamma-ray bursts. (1991 - 2000) Copernicus - Lifetime: Aug 1972 - late 1980, Energy Range: 0.5 - 10 keV COS-B - Lifetime: Aug 1975 - Apr 1982, Energy Range: 2 keV - 5 GeV« DXS - Lifetime: Jan 1993, Energy Range: 0.15 - 0.28 keV, Shuttle-borne instrument Einste in - Lifet ime: Nov 1978 - Apr 1981, Energy Range: 0. 2 - 20 ke V EUVE - Extreme Ultraviolet Explorer. First dedicated extreme ultraviolet mission. (1992 - 2001) EXOSAT - Lifetime: May 1983 - Apr 1986, Energy Range: 0.05 - 20 keV, 90-hour highly eccentric Earth orbit Ginga - Lifetime: Feb 1987 - Nov 1991, Energy Range: 1 - 400 keV Granat - Lifetime: Dec 1989 - Nov 1998,,gyg Energy Range: 2 keV - 100 MeV Hakucho - Lifetime: Feb 1979 - Apr 1985, Energy Range: 0.1 - 100 keV HEAO-1 - Lifetime: Aug 1977 - Jan 1979, Energy Range: 0.2 - 10 keV HEAO-3 - Lifetime: Sep 1979 - May 1981, Energy Range: 50 keV - 10 MeV HETE-2 - Lifetime: Oct 2000 - Oct 2006, Energy Range: 0.5 - 400 keV, designed to detect and localize gamma- ray bursts OSO-7 - Lifetime: Sep 1971 - Jul 1974, Energy Range: 1 keV - 10 MeV OSO-8 - Lifetime: Jun 1975 - Sep 1978, Energy Range: 0.15 keV - 1 MeV ROSAT - Roentgen Satellite. All-sky survey in the soft X-ray band with catalog containing more than 150000 objects. (1990 - 1999) RXTE - RiRossi X-ray Timi ng Exp lorer. Life time: Dec 1995 - Jan 2012, Energy Range: 1. 5 - 240 ke V, very large collecting area and all-sky soft X-ray monitor, precision timing with 1 microsecond resolution SAS-2 - Lifetime: Nov 1972 - Jun 1973, Energy Range: 20 Mev - 1 GeV SAS-3 - Lifetime: May 1975 - 1979, Energy Range: 0.1 - 60 keV Tenma - Lifetime: Feb 1983 - late 1984, Energy Rang e: 0.1 - 60 keV Uhuru - Lifetime: Dec 1970 - Mar 1973, Energy Range: 2 - 20 keV Vela 5B - Lifetime: May 1969 - Jun 1979, Energy Range: 3 - 750 keV SpacePart12‐4th ‐ CERN 2012/11/5 ‐ http://heasarc.nasa.gov/docsE.Costa /heasarc/missions/past.html 7 operative missions with X-ray capabilities AGILE, (2007 - present) All these missions are observatories open to Chandra (1999 - present) the community worldwide. Observations may Fermi (2008 -present) be request on the basis of competitive AOO. INTEGRAL (2002 - present) At least data are publicaly distributed. MAXI (ISS) (2009 - present) Also missions conceived as «experiments» NuSTAR (2012 - present) after succesful peformance are converted Suzaku (2005 - present) into observatories. Swift (2004 - present) This is a major difference between High XMM-Newton (1999 - present) energy Astrophysics and High Energy Physics The cost to mantain a mission is much lower than that to make a new one. Sppyecially for telescop es there is a larg e room for new ideas and for serendipitous disoveris. Conversely for this reason every time a hot topic is singled out the first check is whether it can be solved by pointing an existing mission. SpacePart12-4th - CERN 2012/11/5 - E.Costa X-ray Astronomy covers almost all fields of Astronomy The first discoveres were the binaries incllduding White Dwarf es , Nutron Stars, Black Holes. With UHURU satellite 350 sources including a few extragalactic (mainly AGNs). In galaxy clusters there is a large amount of hot gas: the mass of the universe is 3 times wha t previous ly known. Einstein satellite was the first to use the X-ray optics allowing for imaging extended sorces and increasing the sensitivity of many orders of mgnitude. Einstein took images and spectra of SuperNova Remnants and of Clusters, found coronal emission of stars, sources in other galaxies and enormously increased the sample of galactic sources and especially of extragalactic ones. ROSAT satellite, also based on an X-ray telescope, made the first deep survey of all the sky. Moreover discovered the emission from the moon and from comets and measured the flux of brighter sorces for around15 years.. XTE disvered quasi pulsations from neutron stars up to 1 kHz frequency. Beppo SAX made the first broad band sectra from 0.1 to 300 keV and discvered and localized the afterglow of GammaRay Burst. SWIFT di scovered the fuzzy behavior of early GRBs and conti nuously maps the Hard X-ray sky. INTEGRAL mapped the 511 keV line i the galaxy and surveys hard X-ray sky. But far the largest amount of data have been collected in the last 10 years with the two big telescopes Chandra and XMM. SpacePart12-4th - CERN 2012/11/5 - E.Costa Two diverging drivers: trade-off or complementariety? Since the beginning X-ray enlhlighten the astrophysics of high energy processes with a wealth of predictions in terms of spectra, images, variability and polarization. All big discover ies are associtdiated with an innova tive thitechnique. From the geiger to the proportional counter From the rockett to the satellite From the collimator to the optics From small area to large area From proportional counters to CCDs (to gratings) From long term planning to fast pointing ………. Thence scientist work for a continuous improvement of measure techniques in order to: 1) Extend the observable quantities 2) Improve the sensitivity in the measurements in the range where the sensi ti vi ty is the hhghestighest. I apologize for telling obvious things But which should be the driver for the selection of the next mission [[]s] of X-ray Astronomy is not obvious at all. SpacePart12-4th - CERN 2012/11/5 - E.Costa The tremendus power of X-ray optics An X-ray optics is based on the double reflection at grazing incidence on two surfaces (usually) shaped as a paraboloid/hyperboloid. It is a real imag ing dev ice. Photons from a certain direction ae focussed in a point of the focal plane. The flux of a source, colleted on an equivalent surface of hundreds cm2 is to be compared with the background of 0.1 mm2 of the detector. Since the sensitivity to faint sources is imited from background the X-ray optics allow to: • Image extended sources (e.g. clusters or SN Remnants) • Precisely localize sources (and solve ambiguity) • Extend sensitivity to weak sources (up to 5 orders of magnitude) without abnormal increase of the surface. But this is not for free. The making of X-ray optics is very costly, requires long ppyayloads. The response qqyuickly decreases with the energy. No high qqyuality optics extends to more than 10 keV. The feld of view is small. Aberrations are proportional to the off-set.. Optics can host spectrometers (microcalorimeters or gratings) and extend the space of observables. Sometimes different solutions (including optics of less quality) are needed. SpacePart12-4th - CERN 2012/11/5 - E.Costa Existing and in advanced state Existing • FERMI and AGILE are γ-ray missions with some limited X-ray capabilitiesmainly oriented to complement the γ-ray measurements • MMX,AXI, aboard the ISS is an all-sky mmnonitor. It detects trannnsient and burst sources and monitors all sources including a good number of extragalactic. After the switch-off of XTE it is the only all-sky monitor in soft/medium X-rays. Around 400 sources. • Chandra is the best X-ray imager ever made (0.5 arcesec). Excepional images. Good spectroscopy (CCDs and gratings). Maximum sensitivity for deep fields. • XMM is the Workhorse of X-Ray Astronomy. Good but not exceptional imaging capabilities (15 arcseconds) but large area and good energy resolution (CCDs and gratings). • INTEGRAL isthe onlymiiissions studidying soft gamma rays wihith imaging and spectroscopic capabilities. It has also surveying the sky in Hard X-Rays with a sensitivity increasing with time. • SWIFT is dtddevoted to stdtudy GRBs btbut isalso prodiducing a survey of Hard X-ray Sky and acting as an X-ray telescope with CCD open to the community.
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