CSO Bolocam 1.1 mm continuum mapping of the Braid Nebula star formation region in Cygnus OB7

We present a 1.1 mm map of the Braid Nebula star formation region in Cygnus OB7 taken using Bolocam on the Caltech Submillimeter Observatory. Within the 1 deg2 covered by the map, we have detected 55 cold dust clumps all of which are new detections. A number of these clumps are coincident with IRAS point sources although the majority are not. Some of the previously studied optical/near-IR sources are detected at 1.1 mm. We estimate total dust/gas masses for the 55 clumps together with peak visual extinctions. We conclude that over the whole region, approximately 20% of the clumps are associated with IRAS sources suggesting that these are protostellar objects. The remaining 80% are classed as starless clumps. In addition, both FU Orionis (FUor) like objects in the field, the Braid Star and HH 381 IRS, are associated with strong millimeter emission. This implies that FUor eruptions can occur at very early stages of pre-main-sequence life. Finally, we determine that the cumulative clump mass function for the region is very similar to that found in both the Perseus and Ï? Ophiuchus star-forming regions. © 2011. The American Astronomical Society. All rights reserved

V2494 cyg: A unique FU ori type object in the cygnus OB7 complex

A photometric and spectral study of the variable star V2494 Cyg in the L 1003 dark cloud is presented. The brightness of the star, formerly known as HH 381 IRS, increased by 2.5 mag in R (probably in the 1980s) and since then has remained nearly constant. Since the brightness increase, V2494 Cyg has illuminated a bipolar cometary nebula. The stellar spectrum has several features typical of the FU Ori (FUor) type, plus it exhibits very strong Ha and forbidden emissionlines with high-velocity components. These emission lines originate in the Herbig-Haro (HH) jet near the star. The kinematic age of the jet is consistent with it forming at the time of the outburst leading to the luminosity increase. V2494 Cyg also produces a rather extended outflow; it is the first known FUor with both an observed outburst and a parsec-sized HH flow. The nebula, illuminated by V2494 Cyg, possesses similar morphological and spectral characteristics to Hubble's variable nebula (R Monocerotis/NGC 2261). © 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society

GM 2-4 - a signpost for low and intermediate mass star formation

We present a multi-wavelength study of the region towards the GM 2-4 nebula and the nearby source IRAS 05373+2340. Our near-infrared H2 1-0 S(1) line observations reveal various shock-excited features which are part of several bipolar outflows. We identify candidates for the driving sources of the outflows from a comparison of the multi-waveband archival data-sets and SED modelling. The SED spectral slope (\alpha(IRAC)) for all the protostars in the field was then compared with the visual extinction map. This comparison suggests that star formation is progressing from NE to SW across this region

The cores of ρ Ophiuchus

Abstract. We search for dense cores and the molecular outflows which accompany stellar birth in the rho Ophiuchi cloud L1688 through two unbiased wide-field surveys. A solution to the problem of how to avoid the dissolution of brown dwarf binaries is suggested: binaries forming in the widely scattered low-mass cores are not susceptible to disruption since the region is dynamically relaxed. We also find weak H 2 outflows which may be driven by proto-brown-dwarfs. The dense cores are detected through continuum emission from associated dust grains at 1.2 mm. Covering over 1 square degree, we detect many previously unknown sources, ranging from extended cores to those harbouring Class II young stars. We analyse the mass and spatial distributions. The core mass function resembles the stellar initial mass function, both within the tightly-packed clumps as well as within the less-crowded surroundings. The cores display a hierarchical spatial distribution with no preferred separation scale length. The orientations of the major axes of cores are consistent with an isotropic distribution whereas the orientations of core pairs possess a preferential direction on all separation scales, consistent with the filamentary cloud appearance. Our near-infrared survey for molecular hydrogen emission covers 35 × 35 . We detect several new H 2 flows but the total number of detected outflows is low and is consistent with the paucity of Class 0 and Class 1 sources in the molecular cloud. Most of the candidate driving sources are deeply embedded in dense cores. A very young outflow arises from the newly discovered Class 0 source MMS 126. Flow directions are generally NE-SW, perpendicular to the above preferred direction. The apparent extents of molecular flows are related to either the widths or the separation between cloud filaments

Gm 2-4: a signpost for low- and intermediate-mass star formation★

We present a multi-wavelength study of the region towards the GM 2-4 nebula and the nearby source IRAS 05373+2340. Our near-infrared H2 10 S(1) line observations reveal various shock-excited features which are part of several bipolar outflows. We identify candidates for the driving sources of the outflows from a comparison of the multi-waveband archival data sets and spectral energy distribution (SED) modelling. The SED spectral slope () for all the protostars in the field was then compared with the visual extinction map. This comparison suggests that star formation progresses from north-east to south-west across this region

An outbursting protostar of the FU Orionis type in the Cygnus OB7 molecular cloud

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 active star formation region containing RNO 127, 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-Pérot 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 mag. 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

Near-ir spectroscopy of young stars in the braid nebula star formation region in cygnus ob7

We present 1.4-2.5 mu m integral field spectroscopy of 16 stars in the Braid Nebula star formation region in Cygnus OB7. These data form one aspect of a large-scale multiwavelength survey aimed at determining an unbiased estimate of the number, mass distribution, and evolutionary state of the young stars within this 1 deg(2) area of the previously poorly studied Lynds 1003 molecular cloud. Our new spectroscopic data, when combined with Two Micron All Sky Survey near-IR photometry, provide evidence of membership of many of these objects in the regions\u27 pre-main-sequence population. We discuss both the characteristics of the young stars found in the region and the level of starforming activity present

Near-ir spectroscopy of young stars in the braid nebula star formation region in cygnus ob7

We present 1.4-2.5 mu m integral field spectroscopy of 16 stars in the Braid Nebula star formation region in Cygnus OB7. These data form one aspect of a large-scale multiwavelength survey aimed at determining an unbiased estimate of the number, mass distribution, and evolutionary state of the young stars within this 1 deg(2) area of the previously poorly studied Lynds 1003 molecular cloud. Our new spectroscopic data, when combined with Two Micron All Sky Survey near-IR photometry, provide evidence of membership of many of these objects in the regions\u27 pre-main-sequence population. We discuss both the characteristics of the young stars found in the region and the level of starforming activity present

A wide-field narrowband optical survey of the braid nebula star formation region in cygnus OB7

We study the population of Herbig-Haro (HH) flows and jets in an area of Cygnus OB7 designated the Braid Nebula star formation region. This complex forms part of the L 1003 dark cloud, and hosts two FU Orionis (FUor)-like objects as well as several other active young stars. To trace outflow activity and to relate both known and newly discovered flows to young star hosts we intercompare new, deep, narrowband H? and [S II] optical images taken on the Subaru 8m Telescope on Mauna Kea, Hawaii. Our images show that there is considerable outflow and jet activity in this region suggesting the presence of an extensive young star population. We confirm that both of the FUor-like objects drive extensive HH flows and document further members of the flows in both objects. The L1003 star formation complex is a highly kinematically active region with young stars in several different stages of evolution. We trace collimated outflows from numerous young stars although the origin of some HH objects remains elusive