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Post Info TOPIC: HBC 722
Blobrana


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RE: HBC 722
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Title: Revealing The Millimetre Environment of the New FU Orionis Candidate HBC722 with the Submillimeter Array
Authors: Michael M. Dunham, Hector G. Arce, Tyler L. Bourke, Xuepeng Chen, Tim A. van Kempen, Joel D. Green

We present 230 GHz Submillimeter Array continuum and molecular line observations of the newly discovered FUor candidate HBC722. We report the detection of seven 1.3 mm continuum sources in the vicinity of HBC722, none of which correspond to HBC722 itself. We compile infrared and submillimetre continuum photometry of each source from previous studies and conclude that three are Class 0 embedded protostars, one is a Class I embedded protostar, one is a Class I/II transition object, and two are either starless cores or very young, very low luminosity protostars or first hydrostatic cores. We detect a northwest-southeast outflow, consistent with the previous detection of such an outflow in low-resolution, single-dish observations, and note that its axis may be precessing. We show that this outflow is centred on and driven by one of the nearby Class 0 sources rather than HBC722, and find no conclusive evidence that HBC722 itself is driving an outflow. The non-detection of HBC722 in the 1.3 mm continuum observations suggests an upper limit of 0.02 solar masses for the mass of the circumstellar disk. This limit is consistent with typical T Tauri disks and with a disk that provides sufficient mass to power the burst.

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Blobrana


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Title: The new FUor star HBC 722 - one year after the outburst
Authors: Evgeni Semkov, Stoyanka Peneva

The first results from studies of the new FU Orionis star found in the field of NGC 7000 are presented in the paper. During the year passing from the registration of outburst at fourteen papers containing data from observations of this object have been published in the astronomical journals. These publications present photometric and spectral observations of HBC 722 ranging from the far infrared to X-ray wavelength region. HBC 722 is the first FU Orionis object, whose outburst was observed from its very beginning in all spectral ranges. We expect that the interest in this object will increase in the coming years and the results will help to explore the nature of young stars.

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Blobrana


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Title: Disentangling the Environment of the FU Orionis Candidate HBC 722 with Herschel
Authors: Joel D. Green, Neal J. Evans II, Ágnes Kóspál, Tim A. van Kempen, Gregory Herczeg, Sascha P. Quanz, Thomas Henning, Jeong-Eun Lee, Michael M. Dunham, Gwendolyn Meeus, Jeroen Bouwman, Ewine van Dishoeck, Jo-hsin Chen, Manuel Güdel, Stephen L. Skinner, Manuel Merello, David Pooley, Luisa M. Rebull, Sylvain Guieu

We analyse the submillimetre emission surrounding the new FU Orionis-type object, HBC 722. We present the first epoch of observations of the active environs of HBC 722, with imaging and spectroscopy from PACS, SPIRE, and HIFI aboard the Herschel Space Observatory, as well as CO J= 2-1 and 350 um imaging (SHARC-II) with the Caltech Submillimeter Observatory. The primary source of submillimetre continuum emission in the region -- 2MASS 20581767+4353310 -- is located 16$\arcsec$ south-southeast of the optical flaring source while the optical and near-IR emission is dominated by HBC 722. A bipolar outflow extends over HBC 722; the most likely driver is the submillimetre source. We detect warm (100 K) and hot (246 K) CO emission in the surrounding region, evidence of outflow-driven heating in the vicinity. The region around HBC 722 itself shows little evidence of heating driven by the new outbursting source itself.

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