HiRes DECONVOLVEDSPITZERIMAGES OF 89 PROTOSTELLAR JETS AND OUTFLOWS: NEW DATA ON THE EVOLUTION OF THE OUTFLOW MORPHOLOGY

Abstract

To study the role of protosellar jets and outflows in the time evolution of the parent cores and the protostars, the astronomical community needs a large enough data base of infrared images of protostars at the highest spatial resolution possible, to reveal the details of their morphology. Spitzer provides unprecedented sensitivity in the infrared to study both the jet and outflow features, however its spatial resolution is limited by its 0.85m mirror. Here we use a high resolution deconvolution algorithm, "HiRes", to improve the visualization of spatial morphology by enhancing resolution (to sub-arcsecond levels in the IRAC bands) and removing the contaminating sidelobes from bright sources in a sample of 89 protostellar objects. These reprocessed images are useful to detect: (i) wide angle outflow seen in scattered light; (ii) morphological details of H 2 emission in jets and bow shocks; and (iii) compact features in MIPS 24 µm images as protostar/disk and atomic/ionic line emissions associated with the jets. The HiRes fits image data of such a large homogeneous sample presented here will be useful to the community in studying these protostellar objects. To illustrate the utility of this HiRes sample, we show how the opening angle of the wide angle outflows in 31 sources, all observed in the HiRes processed Spitzer images, correlates with age. Our data suggest a power law fit to opening angle versus age with an exponent of ∼ 0.32 and 0.02, respectively for ages ≤ 8000 yr and ≥ 8000 yr.

Geometric and Kinematic Structure of the Outflow/Envelope System of L1527 Revealed by Subarcsecond-Resolution Observation of Cs

“…outflow by using the parabolic model considering the inclination angle. The results quantitatively supports the trend suggested previously (Arce & Sargent 2006;Seale & Looney 2008;Velusamy et al 2014). Figure 11 shows a semi-log plot of v 0 /DR 0 versus dynamical timescale t dyn .…”

“…If the emission in the L′ band is weakened by the outflow cavity wall, the brightness on the two sides of the protostar depends on the distribution of matter in the outflow cavity, and the brightness asymmetry cannot constrain the direction of the inclination. Very recently, Velusamy et al (2014) reported that the Spitzer 3.6 μm HiRes deconvolved image shows the brightness asymmetry of the outflow cavity in the vicinity of the protostar that is opposite to that reported by Tobin et al (2008Tobin et al ( , 2010. The result by Velusamy et al (2014) seems consistent with the positive inclination angle that we found in this study.…”

“…Very recently, Velusamy et al (2014) reported that the Spitzer 3.6 μm HiRes deconvolved image shows the brightness asymmetry of the outflow cavity in the vicinity of the protostar that is opposite to that reported by Tobin et al (2008Tobin et al ( , 2010. The result by Velusamy et al (2014) seems consistent with the positive inclination angle that we found in this study. Thus, the observations of the morphology of the cavity reflection seem inconsistent with each other.…”

ALMA Observations of Dust Polarization and Molecular Line Emission from the Class 0 Protostellar Source Serpens SMM1

“…Some studies have found a correlation between outflow opening angle and protostellar age, where older sources have wider outflows (Arce & Sargent 2006). However, more recent infrared scattered-light studies have come to a variety of conclusions, suggesting that the relationship between outflow opening angle and age is not yet certain (Seale & Looney 2008;Velusamy et al 2014;Booker et al 2017;Hsieh et al 2017). …”

X-Ray Emission From Stellar Jets by Collision Against High-Density Molecular Clouds: An Application to Hh 248

“…X-ray emission from protostellar jets was first reported by Pravdo et al (2001), who detected an X-ray source coincident with HH 2 that was not associated with any other galactic or extragalactic source (see Velusamy et al 2014). Later, Favata et al (2002) detected X-ray emission from HH 154, a jet associated with the protostar L1551 IRS5 in the Taurus Molecular Cloud (see also Bally et al 2003;Bonito et al 2004Bonito et al , 2011Favata et al 2006).…”