By National Astronomical Observatories, Chinese Academy of Sciences
October 4, 2022
X-ray imaging by flexing light rays (focusing) is infamously challenging due to the high energy of X-ray photons, and it is even more tough to acquire clear images from a large field of view. Even though these outcomes are still initial and extensive information processing must be done, the test flight shows that even a one-shot observation can cover X-ray sources from all instructions within the observed spot of sky, consisting of stellar-mass black holes and neutron stars. The information from these observations supply information about how X-ray radiation from such celestial bodies changes over time, as well as the X-ray spectra of these celestial bodies. The outcomes demonstrate that even a one-shot observation can cover the whole of this galaxy, detecting several X-ray sources, consisting of black holes, neutron stars, and supernova residues. In its future observations, the imager is anticipated to effectively keep an eye on the X-ray irregularity of celestial bodies and discover new short-term sources.
EP-WXT Pathfinder targets an area of the Galactic center at the core of the Milky Way. Inset shows the 800-second time-lapse picture from the observation. Credit: CAS/ESA/Gaia/ DPAC.
EP-WXT Pathfinder has actually released its first results.
EP-WXT Pathfinder, an experimental prototype of a module that will ultimately belong to the wide-field X-ray telescope (WXT) on the astronomical satellite Einstein Probe (EP), recently launched its very first results. These outcomes include an 800-second X-ray time-lapse picture of a section of the Galactic center, a thick location in the core of our own galaxy, the Milky Way.
These images, taken by the very first really wide-field X-ray focusing imaging telescope ever launched in area, are the very first wide-field X-ray pictures of our universe that are now available to the public.
Researchers from the Chinese Academy of Sciences (CAS) provided the findings at the Second China Space Science Assembly in Taiyuan, China.
Because the first X-ray signals from the outermost reaches of deep space were discovered 60 years earlier, there hasnt been a wide-field X-ray focusing telescope offered for X-ray studies and keeping an eye on till Pathfinder.
To check the modules performance while in orbit, the Pathfinder was sent out into space. The experimental trip will lay the foundation for EPs upcoming in-orbit clinical objective as it collects data in the soft X-ray waveband.
The initial X-ray “time-lapse photograph” (right) in 0.5– 4 keV band as the outcome of a 700-second one-shot observation of the Large Magellanic Cloud (LMC), our next-door neighbor galaxy, in contrast with the DSS optical picture of LMC. Credit: CAS/DSS.
EP will explore open questions in time-domain astrophysics through the observation of transients. The mission is sponsored by CAS in cooperation with the European Space Agency (ESA) and the Max Planck Institute for Extraterrestrial Physics and is expected to zip completion of 2023.
The WXT test module covers a field of vision approximately 340 square degrees (18.6 ° × 18.6 °) wide, that makes it the very first really wide-field X-ray focusing imaging telescope. X-ray imaging by bending light rays (focusing) is notoriously challenging due to the high energy of X-ray photons, and it is much more difficult to acquire clear images from a large field of vision. Thanks to a modern technology called lobster-eye micropore optics, the test module boasts a field of view a minimum of 100 times those of other focusing X-ray imagers. The complete WXT to fly aboard EP will be made up of 12 identical modules, covering a field of vision approximately 3,600 square degrees large.
Throughout the test flight, Pathfinder conducted an overall of four days of in-orbit experimental observations and acquired authentic X-ray spectra and images based upon genuine measurements.
The key elements of Pathfinder consist of the X-ray imaging mirror assembly, which features an array of 36 micropore lobster-eye plates and a focal-plane detector made up of four sets of large-format imaging sensors.
X-ray image of the Cygnus Loop nebula (2.5-degree size) was obtained with a number of observations totaling 2,400 seconds. Credit: CAS.
Despite the fact that these outcomes are still initial and extensive data processing must be done, the test flight shows that even a one-shot observation can cover X-ray sources from all directions within the observed patch of sky, including stellar-mass great voids and neutron stars. The observation also caught the brightening of X-rays from a double star containing a neutron star. The information from these observations supply information about how X-ray radiation from such heavenly bodies changes gradually, as well as the X-ray spectra of these celestial bodies. The spectra and images resulting from the test observations are highly consistent with simulations.
The outcomes show that even a one-shot observation can cover the whole of this galaxy, detecting multiple X-ray sources, consisting of black holes, neutron stars, and supernova remnants. In its future observations, the imager is expected to efficiently keep an eye on the X-ray variability of celestial bodies and discover new short-term sources.
According to Dr. Yuan Weimin, primary investigator (PI) of the EP objective and scientist at the National Astronomical Observatories of the Chinese Academy of Sciences (NAOC), preliminary results show that “the instrument runs smoothly” and satisfies EP WXT module requirements. “Its interesting to see the decade-long effort bearing its very first fruit,” he smiled.
Other scientists included with the EP objective were likewise pleased.
Dr. Zhang Chen, PI of the WXT mirror assembly, said the results assure “abundant, top quality information” after the probe is introduced.
Teacher Paul OBrien, an ESA-appointed scientist for the EP mission and researcher at the University of Leicester, stated the outcomes are “actually remarkable.”.
” We have actually been awaiting a true wide-field, soft X-ray imager for numerous decades, so it is fantastic to see the WXT test module in flight on EP-WXT Pathfinder,” said Professor Richard Willingale, Professor OBriens coworker at the University of Leicester.