We present a study of dense molecular gas kinematics in seventeen nearby protostellar systems using single-dish and interferometric line observations. The non-axisymmetric envelopes around sample Class 0/I protostars were mapped the N2H+ (J=1-0) tracer with IRAM 30m, CARMA PdBI as well NH3 (1,1) VLA. emission is used to construct line-center velocity linewidth maps for all sources examine kinematic structure on spatial scales from 0.1 pc ~1000 AU. direction large-scale gradients mapping...

Abstract New multi-wavelength Karl G. Jansky VLA observations of CKR02A, the compact radio source in center HII region NGC 6334A, are presented. The were carried out five epochs and included frequency ranges 8.0 - 12.0 GHz (X-band), 18.0 26.0 (K-band), 29.0 37.0 (Ka-band). is detected resolved all observed bands. shows a clear arc-shaped structure consistent with bow shock. analysis spectral index maps indicates that its α = −0.68 ± 0.17, suggesting emission non-thermal. Two astronomical...

Abstract Oph-S1 is the most luminous and massive stellar member of nearby Ophiuchus star-forming region. Previous Very Long Baseline Array (VLBA) observations have shown it to be an intermediate-mass binary system (∼5 M⊙) with orbital period about 21 months, but a paucity radio detections secondary near periastron could potentially affected determination its parameters. Here, we present nine new VLBA focused on passage in early 2024. We detect primary all at five epochs, including three...

The Pipe Nebula is a massive, nearby dark molecular cloud with low star formation efficiency which makes it good laboratory in to study the very early stages of process. largely filamentary and appears be threaded by uniform magnetic field at scales few parsecs, perpendicular its main axis. only locally perturbed regions, such as active cluster-forming core B59. aim this investigate primordial conditions low-mass pre-stellar cores how they relate local cloud. We used IRAM 30 m telescope...

The radio-knots of the Herbig–Haro (HH) 80/81/80N jet extend from HH 80 object to recently discovered Source 34 and has a total projected size 10.3 pc, constituting largest collimated radio-jet system known so far. It is powered by bright infrared source IRAS 18162−2048 associated with massive young stellar object. We report 6 cm JVLA observations that, compared previous VLA carried out in 1989, allow us derive proper motions 80, 81, 80N radio knots located about 2.5 pc away projection...

We present 6 and 20 cm Jansky Very Large Array/Very Array observations of the northern head HH 80/81/80N jet, one largest collimated jet systems known so far, aimed to look for knots farther than 80N, jet. Aligned with 10' northeast we found a radio source not reported before, negative spectral index similar that 80, 81, 80N. The fit precessing model including new source, shows position this is close path resulting from modeling. If belongs its derived size dynamical age are 18.4 pc >9 × 103...

Abstract We present sensitive high angular resolution (∼0.″1–0.″3) continuum Atacama Large Millimeter/Submillimeter Array (ALMA) observations of the archetypal hot core located in Orion Kleinmann-Low (KL) region. The were made five different spectral bands (bands 3, 6, 7, 8, and 9) covering a very broad range frequencies (149–658 GHz). Apart from well-known millimeter emitting objects this region (Orion Source I BN), we report first submillimeter detection three compact sources (ALMA1–3)...

The Pipe nebula is a massive, nearby, filamentary dark molecular cloud with low star-formation efficiency threaded by uniform magnetic field perpendicular to its main axis. It harbors more than hundred, mostly quiescent, very chemically young starless cores. is, therefore, good laboratory study the earliest stages of process. We aim investigate primordial conditions and relation among physical, chemical, properties in evolution low-mass used IRAM 30-m telescope map 1.2 mm dust continuum...

Abstract We present Atacama Large Millimeter/Submillimeter Array 1.3 mm continuum and C 18 O(2−1), N 2 D + (3−2), 13 CS(5−4), 12 CO(2−1) line sensitive high angular resolution (∼0.″3) observations of the famous Carina pillars protostellar objects HH 901/902. Our reveal for first time, bipolar CO outflows dusty disks (plus envelopes) that are energizing extended irradiated Herbig–Haro (HH) far from pillars. find masses disks+envelopes about 0.1 M ⊙ between 10 −3 −4 , which suggests they could...

Ultra-compact (UC)H ii regions represent a very early stage of massive star formation. The structure and evolution these are not yet fully understood. Interferometric observations showed in recent years that compact sources uncertain nature associated with some UCH regions. To examine this, we carried out VLA 1.3 cm the A configuration selected order to report additional cases embedded With observations, find 13 9 Although cannot establish an unambiguous for newly detected sources, assess...

We analyze high-resolution Very Large Array and Jansky continuum observations of the M8 region carried out at several epochs that span a period 30 yr. Our maps reveal two compact sources. One is associated with Her 36 SE, possible companion O7 luminous massive star 36, other to G5.97-1.17, whose proplyd nature was previously established. With analyzed data, we do not find significant time variability in any these The derived spectral index $\ge 0.1$ for Her~36 marginal offset radio emission...

We present a Berkeley–Illinois–Maryland Association Array molecular survey of the star-forming core ahead HH 80N, optically obscured northern counterpart Herbig-Haro objects 80/81. Continuum emission at 1.4 mm and 8 μm is detected center core, which confirms presence an embedded very young stellar object in core. All species arise ringlike structure, most clearly traced by CS (2–1) emission. This ring suggests that strong depletion occurs inner part (at radius ≃0.1 pc densities higher than...

We present observations of continuum emission in the mid-infrared to millimeter wavelength range, complemented with ammonia observations, dense core ahead radio Herbig–Haro (HH) object HH 80N, found GGD 27 region. The all observed bands peaks at same position, consistent presence an embedded object, 80N-IRS1, within core. distribution Very Large Array is well correlated that dust, suggesting photochemical effects caused by nearby do not play important role shaping this particular molecular...

Context. Recent high angular resolution radio observations of the ultracompact H ii region W3(OH) confirm presence an extremely compact (0.′′05), time-variable source near its center.

We present a catalog of radio sources the M 17 region based on deep X band observations centered at 10 GHz obtained with Jansky Very Large Array in A configuration. detect total 194 sources, 12 them extended and 182 compact. find that significant fraction (at least 40% our catalog) have suspected gyrosynchrotron emission associated stellar coronal emission. By comparing luminosities their ray counterparts, when available, we they are underluminous rays respect to G\"udel Benz relation, but...

We present VLA NH3 and PdBI NH2D H13NC observations of the star forming core ahead HH 80N, optically obscured northern counterpart Herbig-Haro objects 80/81. The main goal is to determine kinematical information high density regions ($n\lesssim 10^5$ cm$^{-3}$), missed in previous works due depletion species observed (e.g. CS). obtained maps show different signatures between eastern western parts core, suggesting a possible dynamical interaction with 80/81/80N outflow. analysis...

Abstract We report dynamical mass measurements of the individual stars in most luminous and massive stellar member nearby Ophiuchus star-forming region, young tight binary system S1. combine 28 archival data sets with seven recent proprietary Very Long Baseline Array (VLBA) observations obtained as part Dynamical Masses Young Stellar Multiple Systems VLBA project (DYNAMO–VLBA), to constrain astrometric orbital parameters system, recover high-accuracy masses. The primary component, S1A, is...

We report dynamical mass measurements of the individual stars in most luminous and massive stellar member nearby Ophiuchus star-forming region, young tight binary system S1. combine 28 archival datasets with seven recent, proprietary VLBA observations obtained as part \textit{Dynamical Masses Young Stellar Multiple Systems VLBA} project (DYNAMO--VLBA), to constrain astrometric orbital parameters system, recover high accuracy masses. The primary component, S1A, is found have a...

(abridged) The HH 80/81/80N jet extends from the 80 object to recently discovered Source 34 and has a total projected size of 10.3 pc, constituting largest collimated radio-jet system known so far. It is powered by IRAS 18162-2048 associated with massive young stellar object. We report 6 cm JVLA observations that, compared previous VLA carried out in 1989, allow us derive proper motions 80, 81 80N radio knots located about 2.5 pc away projection powering source. For first time, we measure...

Abstract We present radio continuum and water maser observations toward the high-mass star-forming region IRAS 23151+5912 from VLA VLBA archive, respectively. detected a source, which seems to be hypercompact HII region. In addition, group about 4″ south source was detected. preliminary results of analysis three epochs masers, are tracing an arc-like structure. However, its kinematics is quite complex, since while one section structure moving away center, another approaching.

We report continuum GMRT observations aimed to explore the behaviour of jet associated with IRAS 16547-4247 at very low frequencies (325 MHz and 610 MHz). The obtained maps reveal an elongated morphology in SE–NW direction. In addition, map shows three knots that seems correspond triple radio source identified as seen higher frequencies. However, 325 MHz, although is also observed, only two appear map. By comparing our knot positions both a precessing model used previous work, we find fall...

We present Very Large Array 7 mm continuum observations of four Ultra-Compact (UC)HII regions, observed previously at 1.3 cm, in order to investigate the nature compact radio sources associated with these regions. detected a total seven sources, them thermal emission, and two have clear non-thermal emission. The emission is consistent presence an ionized envelope, either static (i.e., trapped gravitational radius massive star) or flowing away photo-evaporative flow). On other hand, remains...