X-ray linked star, i.eX-ray binaryIs a type of binary star that emits bright X-ray radiation. One of the binary star systems isCompact star, usuallyneutron starorblack hole。Their typical luminosity is between 10 ^ 36-10 ^ 38 ergs/s, which is 3 to 5 orders of magnitude higher than the luminosity of the whole solar band.X-ray binaries are approachingSilver coreandSilver plateThe direction distribution ofGlobular clusterIt is also distributed in.
X-ray linked star, i.eX-ray binary, is a kind of light emittingX-rayRadiantKonductra, one of the binary star systems isCompact star, usuallyneutron starorblack hole。Their typical luminosity is 10thirty-six-10thirty-eightBetween ergs per second, the luminosity is 3 to 5 orders of magnitude higher than that of the whole solar band.X-ray binaries are approachingSilver coreandSilver plateThe direction distribution ofGlobular clusterIt is also distributed in.
find
Announce
edit
In the 1960s, people used rockets and balloons to identify about 30X-ray source。1964Salpeter andZerdovichEt al. proposed that the Galaxy X-ray source isbinary star Of a neutron star or black holeaccretion Process generated.The first identified X-ray binary isCentaur X-3andHercules X-1。In the 1970s,Uhuru satelliteIt is observed that they haveX-ray pulse, the cycles are 4.84 seconds and 1.24 seconds respectively, and thePeriodic change。X-ray pulsarAfter discoveryClose binaryThe periodic variation of the pulse is caused by the mutual eclipse of two stars.This statement has been widely recognized.
According to the mass of companion stars, X-ray binaries can generally be divided into two categories: high-quality X-ray binaries and low-quality X-ray binaries.
Low-quality X-ray binary
The main star of a low mass X-ray binary is a compact star (neutron star or black hole), and the companion star has a low mass, usually less than one time the mass of the sun, and its orbital period varies from several minutes to hundreds of days.Its X-ray radiation is due to the fact that the companion star is full ofRoche valveSome materials are accreted by the host star, which is called "Roche valve overflow".Their X-ray spectra are relatively soft, and a few of them areX-ray pulse, most haveX-ray burstsAnd quasi periodic oscillations, and feeding rarely occurs.Most of the radiation of low-quality X-ray binaries is emitted in the form of X-ray, so they are relatively bright in the skyX-ray source, but it is very dim in the visible light band,Apparent magnitudeAbout 15 to 20.Up to 2006, about 100 such binary stars have been found in the Milky Way, 13 of which are located inGlobular clusterMedium.They are concentrated along the direction of the galactic nucleus sphere and in globular clusters, whileSilver plateThe upper part is very diffuse, belonging to age 10nineYears oldAstral family。
A typical low mass X-ray binary is 4U1626-67, and its host star is 1.4 times the mass of the sunX-ray pulsar, companion star is 0.1 solar massdwarf star, orbiting the main star in an orbit less than the radius of the sun, with an orbital period of 42 minutes.Hercules X-1 is also a typical low-quality X-ray binary.
High quality X-ray binary
The companion star of a high-quality X-ray binary is a compact star, the main star is a massive star (most of which are higher than 10 times the solar mass), and the spectral type is mostly O, B, usuallyType B stars with obvious hydrogen emission raysorSupergiant。The X-ray radiation of such binary stars is caused by the main starStellar windCaptured by a companion star and falling to the surface of the companion star.The luminosity of high-quality X-ray binaries in the visible light band is usually greater than that of X-ray binaries. The optical luminosity is mainly contributed by the host star, while the X-ray radiation is mainly contributed by the companion star (compact star).The characteristics of its X-ray spectrum are relatively hard, and the time-varying characteristics turn into normal X-ray pulses. Most of them have feeding and no X-ray bursts.Their spatial distribution is relatively concentrated along the direction of the silver plate, belonging to the age of less than 10sevenThe young star family of.
Centaur X-3It is a typical high-quality X-ray binary, which was discovered in 1967 and 1971Ricardo GiacconiEtcUhuru satelliteIt has regular pulses according to the observation data of.CentaurThe main star of X-3 is 20 times the mass of the sunSuperStar, the companion star is aX-ray pulsar, the period is 4.84 seconds, and the orbital period around the main star is 2.1 days.Cygnus X-1It is also a high-quality X-ray binary, and its companion star is generally considered to be ablack hole。
High quality X-ray binaries can be divided into two categories: supergiant/X-ray binaries and beryllium/X-ray binaries.Supergiant/X-ray binaries are characterized by spherically symmetric stellar winds, while beryllium stars/X-ray binaries have disk shaped stellar winds and periodic bursts, usually temporary sources.Research shows that beryllium stars/X-ray binarieslarge、Wheat ZhelunyunThe proportion of the total mass of the Mesozoic Galaxy is far higher than that of the Milky Way, which may be related toAmount of metalof
other
In addition, X-ray binaries between the two have also been found, which are suspected to be classified as medium quality X-ray binaries.Up to 2006, only one such X-ray binary has been found.The central object of the cataclysmic variable star emitting X-rays isWhite dwarf, which is also usually regarded as an X-ray binary.
Up to 2006, the pulse and orbital periods of more than 40 X-ray binaries have been measured, and it is found that their periods are superimposed by countless acceleration and deceleration processes. However, in the long run, the general trend is accelerated rotation.The pulse/orbital period of beryllium stars/X-ray binaries has a significant correlation.In addition, X-ray binaries also have the property of irregular walking.
