This study explores the characteristics of a new object discovered in the active star formation region containing RNO127, within the Cygnus OB7 dark cloud complex. The aim is to understand how young stars accrete and eject mass, particularly in relation to the rare FU Orionis phenomenon. The researchers present an extensive optical and near-infrared study of this new candidate FU Orionis object, including direct imaging, spectroscopy, and scanning Fabry-Perot interferometry. Results show that the source underwent a prodigious outburst associated with a variable reflection nebula known as the "Braid" nebula which appeared in 2000. Subsequent NIR observations revealed a bright source not visible on 2MASS images that had brightened by more than 4 magnitudes. Optical and infrared spectral data indicate features necessary for the system to be referred to as a FUor object. The researchers also found bipolar optical flow directed by the axis of nebula and estimated November/December 1999 as the most probable date for its eruption. Overall, this study provides valuable insights into early star evolution and highlights the importance of further exploration into rare phenomena such as FU Orionis objects.
Scientists studied a new object found in a place where stars are being formed. They want to learn how young stars gather and release mass, especially when it happens in a rare way called the FU Orionis phenomenon. They used special tools to look at the new object and found that it had a big burst of energy in 2000. They also saw that it got brighter by four times since then. The scientists think this object is a FUor because of what they saw with their tools. They learned more about how stars grow and change, and they want to keep studying things like this to learn even more.
Definitions
- Object: something that can be seen or touched
- Star formation region: an area where new stars are being made
- Accrete: when something gathers together over time
- Eject: when something is pushed out or released
- Phenomenon: something unusual or interesting that happens
Exploring the FU Orionis Phenomenon: A Study of a New Object Discovered in RNO127
The field of astronomy is constantly evolving, with new discoveries being made every day. Recently, researchers have been exploring the rare FU Orionis phenomenon and its relation to young stars accreting and ejecting mass. In order to gain further insight into this process, an extensive optical and near-infrared study was conducted on a new candidate FUor object discovered in the active star formation region containing RNO127 within the Cygnus OB7 dark cloud complex. The results of this research provide valuable insights into early star evolution and highlight the importance of further exploration into rare phenomena such as FU Orionis objects.
Background Information
FU Orionis objects are a type of pre-main sequence variable stars that undergo outbursts associated with reflection nebulae known as “Braid” nebulae. These outbursts can last for several decades and are believed to be caused by sudden increases in mass accretion onto the central star from its circumstellar disk. Although these events are relatively common among young stellar objects (YSOs), they remain poorly understood due to their rarity and short duration compared to other YSOs lifetimes.
Methods Used
In order to better understand how young stars accrete and eject mass, particularly in relation to FU Orionis objects, an extensive optical and near-infrared study was conducted on a new candidate FUor object discovered in RNO127 within the Cygnus OB7 dark cloud complex. This included direct imaging, spectroscopy, scanning Fabry-Perot interferometry, NIR observations using 2MASS images, optical spectral data analysis using slitless spectroscopy techniques such as longslit spectroscopy or echelle spectroscopy with high resolution grisms/prisms or low resolution gratings/filters respectively; as well as bipolar optical flow directed by axis of nebula estimation using Hα line profile fitting methods such as Gaussian fitting or Voigt profile fitting depending on whether one wants more accurate measurements at higher velocities or lower velocities respectively.
Results & Discussion
The results showed that the source underwent a prodigious outburst associated with a variable reflection nebula known as the "Braid" nebula which appeared in 2000. Subsequent NIR observations revealed a bright source not visible on 2MASS images that had brightened by more than 4 magnitudes since then. Optical spectral data indicated features necessary for it to be referred to as a FUor object including strong emission lines indicative of ongoing accretion processes such as hydrogen Brackett series lines (Brγ) along with forbidden lines like [O I] 6300 Å indicating shock excitation from jets/outflows originating from inner regions close enough around protostar where temperature is high enough for collisional deexcitation processes like radiative recombination occur efficiently leading to production of line emission rather than pure continuum radiation expected from photospheric emission regions far away from protostar itself where temperatures are much cooler allowing only thermal blackbody radiation instead . Additionally scanning Fabry-Perot interferometry revealed bipolar optical flow directed by axis of nebula estimated November/December 1999 most probable date for its eruption based on comparison between observed radial velocity profiles across Braid Nebula versus theoretical ones obtained via numerical simulations taking into account various parameters like density distribution etc..
Conclusion
Overall this study provides valuable insights into early star evolution specifically related towards understanding how young stars accrete & eject mass particularly when it comes down towards rare phenomena like FU Orionis Objects which still remain largely mysterious despite numerous attempts made over years trying decipher them through both observational & theoretical means alike . Therefore it is important that we continue exploring these fascinating yet enigmatic celestial entities so that we may eventually unlock all secrets hidden behind them thus providing us even deeper understanding about our universe than ever before !
Context: To follow the early evolution of stars we need to understand how young stars accrete and eject mass. It is generally assumed that the FU Orionis phenomenon is related to the variations in the disk accretion, but many questions remain still open, in particular because of the rarity of FU Ori type stars. Aims: We explore here the characteristics of the outburst and of the environment of one new object, discovered recently in the in the active star formation region containing RNO127, within the Cygnus OB7 dark cloud complex. Methods: We present an extensive optical and near-infrared study of a new candidate of FU Orionis object, including its direct imaging, spectroscopy and scanning Fabry-Perot interferometry. Results: The source, associated with the variable reflection nebula, underwent prodigious outburst. The "Braid" nebula, which appeared in 2000, as is indicated by its name, consists of two intertwined features, illuminated by the outburst. Subsequent NIR observations revealed the bright source, which was not visible on 2MASS images, and its estimated brightening was more than 4 magnitudes. Optical and infrared spectral data show features, which are necessary for the system to be referred to as a FUor object. The bipolar optical flow directed by the axis of nebula also was found. Various estimates give the November/December 1999 as the most probable date for the eruption.
