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Stars often form in overcrowded environments. By combining multi-wavelength mission resources such as Chandra in X-rays and Spitzer in the infrared, astronomers are able to resolve ambiguities and gather a much more comprehensive census of clusters' content and individual properties of the population. An example is the development of disks (possibly protoplanetary) around new stars. The discs form with the new star and then evolve for a few million years before dissipating, perhaps leaving the planets behind them. In clustered environments, their development may be influenced by interactions with neighbors.
The stellar discs are warmed by their stars and have been spotted by the infrared emission of hot dust. Young, more advanced, diskless stars do not have this characteristic infrared signature and can therefore be identified as the most advanced of a cluster. Young stars were also found to emit high levels of x-rays relative to stars in the main sequence due to their still-developing internal circulation. (In fact, young stars may have thousands of times more bright x-ray illumination than their older stellar counterparts.) In an overpopulated cluster environment, however, factors other than age could inhibit or disrupt the Disk development, X-ray emission provides an independent tool to identify these young stars without disks.
The group of Serpens South stars, located about 900 light-years away in the direction of the Serpens constellation, is very young and its stars are heavily masked by the thick native dust of its environment. among the youngest regions near us, making it an important test bench for the study of disk evolution in clustered environments. CfA astronomers Elaine Winston and Scott Wolk and two collaborators used data from Chandra and Spitzer to analyze sixty-six young stars in the cluster emitting both infrared and X-rays. stars that seemed to be diskless and old because they did not have the infrared signature of the discs, but because of their X-ray emission, they are still quite young: their disc dissipation does not result in theory.
The team was also able to settle a long-standing dispute over the distance to the cluster. Many astronomers had assumed that it was three thousand light-years away, at the same distance as another group in this region of the sky, but we know that the intrinsic brightness of the young stars in clusters follows a relatively narrow distribution values and the observed X-ray emission of these stars is in contradiction with the estimate of the farthest distance and in favor of the tear value of the light 900.
More information:
E. Winston et al. Chandra Detection of an evolved population of young stars at Serpens South, The Astronomical Journal (2018). DOI: 10.3847 / 1538-3881 / aabe82
Stars often form in overcrowded environments. By combining multi-wavelength mission resources such as Chandra in X-rays and Spitzer in the infrared, astronomers are able to resolve ambiguities and gather a much more comprehensive census of clusters' content and individual properties of the population. An example is the development of disks (possibly protoplanetary) around new stars. The discs form with the new star and then evolve for a few million years before dissipating, perhaps leaving the planets behind them. In clustered environments, their development may be influenced by interactions with neighbors.
The stellar discs are warmed by their stars and have been spotted by the infrared emission of hot dust. Young, more advanced, diskless stars do not have this characteristic infrared signature and can therefore be identified as the most advanced of a cluster. Young stars were also found to emit high levels of x-rays relative to stars in the main sequence due to their still-developing internal circulation. (In fact, young stars may have thousands of times more bright x-ray illumination than their older stellar counterparts.) In an overpopulated cluster environment, however, factors other than age could inhibit or disrupt the Disk development, X-ray emission provides an independent tool to identify these young stars without disks.
The group of Serpens South stars, located about 900 light-years away in the direction of the Serpens constellation, is very young and its stars are heavily masked by the thick native dust of its environment. among the youngest regions near us, making it an important test bench for the study of disk evolution in clustered environments. CfA astronomers Elaine Winston and Scott Wolk and two collaborators used data from Chandra and Spitzer to analyze sixty-six young stars in the cluster emitting both infrared and X-rays. stars that seemed to be diskless and old because they did not have the infrared signature of the discs, but because of their X-ray emission, they are still quite young: their disc dissipation does not result in theory.
The team was also able to settle a long-standing dispute over the distance to the cluster. Many astronomers had assumed that it was three thousand light-years away, at the same distance as another group in this region of the sky, but we know that the intrinsic brightness of the young stars in clusters follows a relatively narrow distribution values and the observed X-ray emission of these stars is in contradiction with the estimate of the farthest distance and in favor of the tear value of the light 900.
More information:
E. Winston et al. Chandra Detection of an evolved population of young stars at Serpens South, The astronomical journal (2018). DOI: 10.3847 / 1538-3881 / aabe82
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