Bipolar CO Research Articles

Gas-Induced Structural Damages in Forward-Bias Bipolar Membrane CO2 Electrolysis Studied by Fast X-ray Tomography

Gas-Induced Structural Damages in Forward-Bias Bipolar Membrane CO₂ Electrolysis Studied by Fast X-ray Tomography

Collision of protostellar jets in the star-forming region IC 1396N

Context. The bright-rimmed cloud IC 1396N is believed to host one of the few known cases where two bipolar CO outflows driven by young stellar objects collide. The CO outflows are traced by chains of knots of H2 emission, with enhanced emission at the position of the possible collision. Aims. The aim of this work is to use the proper motions of the H2 knots to confirm the collision scenario. Methods. A second-epoch H2 image was obtained, and the proper motions of the knots were determined with a time baseline of ~11 yr. We also performed differential photometry on the images to check the flux variability of the knots. Results. For each outflow (N and S), we classified the knots as pre-collision or post-collision. The axes of the pre-collision knots, the position of the possible collision point, and the axes of the post-collision knots were estimated. The difference between the proper motion direction of the post-collision knots and the position angle from the collision point was also calculated. For some of the knots, we obtained the 3D velocity using the radial velocity derived from H2 spectra. Conclusions. The velocity pattern of the H2 knots in the area of interaction (post-collision knots) shows a deviation from that of the pre-collision knots, consistent with being a consequence of the interaction between the two outflows. This favours the interpretation of the IC 1396N outflows as a true collision between two protostellar jets instead of a projection effect.

Multiwavelength investigation of extended green object G19.88-0.53: revealing a protocluster

ABSTRACT A multiwavelength analysis of star formation associated with the extended green object, G19.88-0.53 is presented in this paper. With multiple detected radio and millimetre components, G19.88-0.53 unveils as harbouring a protocluster rather than a single massive young stellar object. We detect an ionized thermal jet using the upgraded Giant Meterwave Radio Telescope, India, which is found to be associated with a massive, dense and hot ALMA 2.7 mm core driving a bipolar CO outflow. Near-infrared spectroscopy with UKIRT–UIST shows the presence of multiple shock-excited H2 lines concurrent with the nature of this region. Detailed investigation of the gas kinematics using ALMA data reveals G19.88-0.53 as an active protocluster with high-mass star-forming components spanning a wide evolutionary spectrum from hot cores in accretion phase to cores driving multiple outflows to possible UCH ii regions.

ALMA Observations of the Extraordinary Carina Pillars: HH 901/902

Abstract We present Atacama Large Millimeter/Submillimeter Array 1.3 mm continuum and C18O(2−1), N2D+(3−2), 13CS(5−4), and 12CO(2−1) line sensitive and high angular resolution (∼0.″3) observations of the famous Carina pillars and protostellar objects HH 901/902. Our observations reveal for the first time, the bipolar CO outflows and the dusty disks (plus envelopes) that are energizing the extended and irradiated Herbig–Haro (HH) objects far from the pillars. We find that the masses of the disks+envelopes are about 0.1 M ⊙ and that the bipolar outflows are between 10−3 and 10−4 M ⊙, which suggests that they could be low- or maybe intermediate-mass protostars. Moreover, we suggest that these young low-mass stars are likely embedded Class 0/I protostars with high-accretion rates. We also show the kinematics of the gas in the pillars together with their respective gas masses (0.1–0.2 M ⊙). We estimate that the pillars will be photoevaporated in 104 to 105 yr by the massive and luminous stars located in the Trumpler 14 cluster. Finally, given the short photoevaporated timescales and that the protostars in these pillars are still very embedded, we suggest that the disks inside of the pillars will be quickly affected by the radiation of the massive stars, forming proplyds, like those observed in Orion.

Surgical techniques for the treatment of tongue tie in children: a comparative study

<p class="abstract"><strong>Background:</strong> Ankyloglossia is another name for tongue tie which in mild form is characterized by mucous membrane bands to complete ankyloglossia whereby the tongue is tethered to the floor of the mouth. It can affect feeding, speech, and oral hygiene as well as have mechanical/social effects. Ankyloglossia can also prevent the tongue from contacting the anterior palate.</p><p class="abstract"><strong>Methods:</strong> The study aimed to find out best possible surgical modality of frenectomy by comparing scalpel, electro-cautery and CO<sub>2</sub> laser in the treatment of tongue tie. This is a prospective randomized clinical trial conducted in the department of ENT, Dr. Shankarrao Chavan Government Medical College, Nanded, Maharashtra. All patients were categorized in to three groups randomly as group A, group B and group C. Each group contains 18 patients and among group A, B and C, frenectomy was done by conventional scalpel technique, by bipolar cautery and CO<sub>2</sub> laser respectively. Then patients were assessed on post op day 1 for symptomatology and inflammatory signs, on post op day 7 for wound healing and any complications and also after 1 month post-op for scar and contracture of wound. </p><p class="abstract"><strong>Results:</strong> In our study, about 61% of population is of male child and female child were remaining 39% (ratio 1.6:1) which is matching with the previous studies. Amongst all patients most common age group is between 1-4 years of age group. Most of the patients were in Kotlow’s class III having severe ankyloglossia (3‑7 mm) followed by class I having Mild ankyloglossia (12‑16 mm).</p><p><strong>Conclusions:</strong> Laser and electro-cautery treatment used for frenectomy operations provides better patient perception in terms of postoperative pain and function than that obtained by the scalpel technique.</p>

Surgical Techniques for the Treatment of Tongue Tie in Children: A Comparative Study

Background: Ankyloglossia is another name for tongue tie which in mild form is characterized by mucous membrane bands to complete ankyloglossia whereby the tongue is tethered to the floor of the mouth. It can affect feeding, speech, and oral hygiene as well as have mechanical/social effects. Ankyloglossia can also prevent the tongue from contacting the anterior palate. Methods: The study aimed to find out best possible surgical modality of frenectomy by comparing scalpel, electro-cautery and CO 2 laser in the treatment of tongue tie. This is a prospective randomized clinical trial conducted in the department of ENT, Dr. Shankarrao Chavan Government Medical College, Nanded, Maharashtra. All patients were categorized in to three groups randomly as group A, group B and group C. Each group contains 18 patients and among group A, B and C, frenectomy was done by conventional scalpel technique, by bipolar cautery and CO 2 laser respectively. Then patients were assessed on post op day 1 for symptomatology and inflammatory signs, on post op day 7 for wound healing and any complications and also after 1 month post-op for scar and contracture of wound. Results: In our study, about 61% of population is of male child and female child were remaining 39% (ratio 1.6:1) which is matching with the previous studies. Amongst all patients most common age group is between 1-4 years of age group. Most of the patients were in Kotlow’s class III having severe ankyloglossia (3‑7 mm) followed by class I having Mild ankyloglossia (12‑16 mm). Conclusions: Laser and electro-cautery treatment used for frenectomy operations provides better patient perception in terms of postoperative pain and function than that obtained by the scalpel technique.

Massive star formation and feedback in W49A: the source of our Galaxy's most luminous water maser outflow

We present high spatial resolution mid-IR images of the ring of UCHII regions in W49A obtained at Gemini North, allowing us to identify the driving source of its powerful H2O maser outflow. These data also confirm our previous report that several radio sources in the ring are undetected in the mid-IR because they are embedded deep inside the cloud core. We locate the source of the water maser outflow at the position of the compact mid-IR peak of source G (source G:IRS1). This IR source is not coincident with any identified compact radio continuum source, but is coincident with a hot molecular core, so we propose that G:IRS1 is a hot core driving an outflow analogous to the wide-angle bipolar outflow in OMC-1. G:IRS1 is at the origin of a larger bipolar cavity and CO outflow. The water maser outflow is orthogonal to the bipolar CO cavity, so the masers probably reside near its waist in the cavity walls. Models of the IR emission require a massive protostar of 45Msun, 3e5Lsun, and an effective envelope accretion rate of 1e-3Msun/yr. Feedback from the central star could potentially drive the H2O maser outflow, but it has insufficient radiative momentum to have driven the large-scale CO outflow, requiring that this massive star had an active accretion disk over the past 10^4 yr. Combined with the spatialy resolved morphology in IR images, G:IRS1 in W49 provides compelling evidence for a massive protostar that formed by accreting from a disk, accompanied by a bipolar outflow.

Mapping the PAHs and H2 in ρ Oph A

AbstractWe present an ISOCAM-CVF map of the ρ Oph A region, covering 3′ × 3′. For each 6 arcsec2 pixel, we extract the spectrum from 5–15 μm. We determine the fluxes of the main PAH features by fitting Lorentzian profiles to the spectrum. The peaks of the various PAH components correspond well with the known positions of the PDRs in this vicinity. The spectrum in several pixels exhibits strong rotational lines of molecular hydrogen which can be used to derive the physical properties of the cloud. The H2 emission traces the hot gas of the bipolar CO outflow from VLA1623.

ISO-Cha I 192: A New Embedded Eruptive Variable in the Chamaeleon I Dark Cloud

We report the detection of an increase of about 2 mag in the 2.2 μm brightness of ISO-Cha I 192, a class I low-mass stellar object thought to be driving a bipolar CO outflow in the Chamaeleon I cloud. This substantial brightness change has taken place during less than 3 yr, from 1996 March to 1999 April. An elongated infrared reflection nebula of size ∼530 AU is seen originating from the star in the direction of the CO bipolar outflow. The historic infrared properties of this young stellar object are examined in order to substantiate the hypothesis that this object is an FU Ori- or EX Lup-type system. Combining our new ground-based near- and mid-infrared photometry with Spitzer IRAC and MIPS broadband fluxes supplemented by published recent spectrophotometry, the spectral energy distribution of this source was constructed. We explored the plausibility of a "standard" configuration of infalling envelope + disk + central source for this object by fitting a two-dimensional radiative transfer code that includes the contributions of each of these components.

Near-infrared polarimetric and spectrometric study of the massive star-forming region S87

We present JHK' imaging polarimetry for the massive star-forming region S87, and K-band spectrometry from 2.0 to 2.35 mum for several infrared sources in the region. The polarimetric patterns of S87E reveal a deeply embedded source (DES-S87) associated with reflection nebulosities. Exciting OH maser and 1.3 mm dust continuum emission, the DES-S87 is suggested to be the youngest star in S87 and the driving source of bipolar CO outflow in the region. A blue cavity is discovered in the [J-K'] color image, to the southwest of DES. Radial dependence of polarization degrees in the cavity could be fitted to the slab model of outflows at an inclination of similar to60degrees out of the plane of the sky (Minchin et al. 1991b). The nebular complex of S87E can be divided into three area. The North nebula, exhibiting a bipolar structure, may represent a bipolar outflow in the northwest-southeast direction. The southwest nebula traces the blueshifted CO outflow and corresponds to the cavity structure discovered in the [J-K'] color image. The nebular structure of S87E suggests a quadrupolar outflow driven by DES-S87. A well-defined centrosymmetric pattern is found in the nebula of S87W with high degrees of polarization, which indicates single scattering off small dust grains in the reflection nebula. The polarimetric vectors around NIRSA show a polarization disk feature oriented in the southeast-northwest direction. Strong Brgamma emission and H-2 emissions are found in the K-band spectra, indicating the presences of strong stellar wind, envelope/disk, shocked gas, and high-density PDRs in the circumstellar environment of S87E and S87W. According to the K-band spectrum, the mass of DES-S87E is estimated to be 20 M-circle dot.

Microscopein situ FTIRS studies of CO adsorption on an array of platinum microelectrodes

An array of platinum microelectrodes was designed and fabricated. The adsorption of CO on such a Pt microelectrode (μ-Pt) was investigated by employing microscopein situ FTIR spectroscopy. A nanostructured film is formed at the surface of μ-Pt (denoted as μ-Pt(R)) when it has been subjected to a treatment of fast potential cycling. Abnormal infrared effects (AIREs) were observed in CO adsorption on the surface of μ-Pt(R), consisting of the inversion of the IR bipolar CO band and the extensively enhanced IR adsorption of COad species.

Very Large Array Observations of High‐Velocity Hiin L1551

We report Very Large Array (VLA) observations of the 21 cm continuum and H I line emission of the neutral wind in the prototypical molecular outflow source L1551. The intermediate-velocity gas observed with the VLA has a velocity with respect to the ambient cloud in the range 10-50 km s-1. Although the blueshifted flow appears weaker than the red one, the maps are indicative of a bipolar morphology confined inside the large-scale CO bipolar lobes. This morphology strongly suggests that the atomic wind is driving the bipolar CO outflow. We fit to the H I line profiles, at four different positions along the redshifted flow axis, a model of a decelerating conical wind that entrains ambient cloud material in a mixing layer at the walls of the cone. This model has a velocity at the axis v0 = 200 km s-1, a mass-loss rate * 9 × 10-7 M☉ yr-1, and a momentum rate 2 × 10-4 M☉ yr-1 km s-1. This is sufficient to drive the observed molecular flow, provided an age ≥8 × 104 yr. We find that the continuum emission spectrum of IRS 5, on scales of 10'', is similar to those of H II regions. This can be explained if most of the emission comes from material ionized by UV radiation from shock fronts due to the interaction of the stellar wind against the ambient cloud. The momentum rate required to produce the extended centimeter emission agrees well with the wind obtained by fitting the line profiles. Finally, the location of a background extragalactic continuum source in the red lobe allows us to probe the physical conditions of the neutral wind. We find that the most probable H I spin temperature in the wind is in the range 25-50 K, in agreement with predictions of the thermal structure of such winds.

Hypoxaemia induced by CO(2) or helium pneumoperitoneum is a co-factor in adhesion formation in rabbits.

A prospective randomized trial in a rabbit model was performed to test the hypothesis that the increase in adhesion formation following prolonged pneumoperitoneum is mediated by peritoneal hypoxaemia. Laparoscopic standardized opposing lesions were performed in uterine horns and pelvic sidewalls by bipolar coagulation and CO(2) laser in six groups of eight animals. Pure CO(2) or helium pneumoperitoneum was used for 10 (groups I and IV) or 45 min (groups II and V) to confirm the effect of duration of pneumoperitoneum and 96% of CO(2) or helium with 4% of oxygen (group III and VI) for 45 min to assess the effect of the addition of oxygen. After 7 days, adhesion formation was scored by laparoscopy. By two-way analysis of variance, total, extent, type and tenacity of adhesion scores increased (P = 0.0003, P = 0.0004, P = 0.0004 and P = 0.004) with increasing duration of pneumoperitoneum and decreased (P = 0.02, P = 0.03, P = 0.01 and P = 0.05) with the addition of oxygen. No differences were found between CO(2) and helium. In conclusion these data confirm the effect of pneumoperitoneum upon adhesions and demonstrate its reduction by oxygen, strongly suggesting that the main cause of adhesion formation is the relatively superficial hypoxaemia produced by the pneumoperitoneum.

A Molecular Counterpart to the HH 1–2 Flow

We present high angular resolution (12''-24'') and high-sensitivity 12CO and 13CO J = 2-1 and J = 1-0 observations of the HH 1-2 outflow. The observations show the molecular counterpart, moving with a velocity of 30 km s-1, of the optical bipolar system driven by the VLA 1 embedded source. Along with the optical jet there are certain regions where the molecular gas reaches deprojected velocities of 100-200 km s-1 and that we interpret as the molecular jet. The bipolar CO outflow has a length of ~260'' with a curved morphology toward the north where it extends beyond the HH 1 object (120''). Two new molecular outflows have been detected, one arising from IRAS 05339-0647, which excites the HH 147 optical flow, and another powered by VLA 2, which drives the HH 144 optical outflow. The molecular outflow driven by the VLA 3 source is also clearly detected and spatially resolved from the VLA 1 main outflow.

A Jet–driven, Extreme High‐Velocity Outflow Powered by a Cold, Low‐Luminosity Protostar near NGC 2023

We have discovered an extreme high-velocity bipolar CO outflow in the vicinity of NGC 2023, with total outflow velocities of ~200 km s-1. At very high velocities this outflow is jetlike with an opening angle ≤4°, while it shows a separate outflow lobe at low velocities. The outflow is bipolar and exhibits a clear mirror symmetry, which suggests that the source powering the outflow is episodic or precessing. The dynamical timescales for the outflow are ≤3000 yr. We identify the source driving the CO jet with a deeply embedded low-luminosity submillimeter double source (separation ~23''), where the primary component lies on the symmetry axis of the outflow and has all the signatures of a protostellar object. Analysis of molecular data and (sub)millimeter photometry suggests that the driving source is cold and compact, with a luminosity of lesssim10 L☉ and a total mass of 1.8-4.6 M☉. It has no near-IR counterpart, it drives an extremely young outflow, and it emits a large fraction of its luminosity in the submillimeter regime. Both millimeter sources have low dust emissivity, β ~ 0.8-1.3, similar to what is found for other class 0 objects, while the surrounding molecular cloud core appears to have a β ~ 2.0, the canonical value for normal interstellar dust in the submillimeter regime.

Multiple CO Outflows in Circinus: The Churning of a Molecular Cloud

We present a millimeter wave study of a cluster of bipolar CO outflows embedded in the western end of the Circinus molecular cloud complex, G317-4, that is traced by very high optical extinction. For an assumed distance of 700 pc, the entire Circinus cloud is estimated to have a mass of about 5E4 solar masses. The opaque western portion that was mapped in this study has a mass of about 10E3 solar masses, contains a number of embedded infrared sources and various compact 1.3 mm continuum sources, and has a remarkable filamentary structure with numerous cavities which appears to be the fossil remnants of past star formation activity. The profusion of outflows in this region are disentangled and linked to driving IRAS sources. Thus, the mapped portion of Circinus contains at least 10 CO emitting molecular outflows. Assuming that star formation has continued at a steady rate for the last several hundred thousand years, the Circinus cloud is expected to have produced dozens of young stars. Their outflows have severely altered the structure and kinematics of this cloud as evidenced by the multitude of prominent cavities and dust filaments that outline their boundaries. This level of star formation activity is consistent with the numerous post-outflow phase H-alpha emission line stars that have been found in this region. The Circinus cloud complex is an archetypical case where star formation activity may have profoundly affected the structure of a molecular cloud, producing its strikingly filamentary and cavitated appearance and providing further evidence that star formation may be a self regulated process.

Shock-excited H[TINF]2[/TINF] Flows in OMC-2 and OMC-3

We report the discovery of nearly a dozen collimated outflows from young stellar objects embedded in the molecular filament that extends north of the Orion Nebula towards the H II region NGC 1977. The large number of nearly coeval outflows and embedded class 0 young stellar objects indicates that the OMC-2/3 region is one of the most active sites of ongoing low- to intermediate-mass star formation known. These outflows were identified in the 2.12 μm v = 1-0 S(1) H2 line during a survey of a 6' × 16' region containing the OMC-2 and OMC-3 cloud cores and over a dozen recently discovered class 0 protostars. We also observe filamentary emission that is likely to trace possible fluorescent H2 in photodissociation regions associated with M43 and NGC 1977. Neither the suspected outflows nor the fluorescent emission are seen at the continuum wavelength of 2.14 μm, which confirms their emission-line nature. Several of the new H2 flows are associated with recently discovered bipolar molecular outflows. However, the most prominent bipolar CO outflow from the region (the MMS 8 flow) has no clear H2 counterpart. Several H2 flows consist of chains of knots and compact bow shocks that likely trace highly collimated protostellar jets. Our discovery of more than 80 individual H2-emitting shocks demonstrate that outflows from young stars are churning this molecular cloud.

Dust Filaments and Star Formation in OMC-2 and OMC-3

We have mapped the 1300 μm dust emission of a 6' × 16' field in the OMC-2 and -3 region and detected an extended filamentary structure with at least 11 embedded condensations in OMC-2 and 10 in OMC-3. Six have been observed previously at 1300 μm, and two were also detected by IRAS. We observed eight of the new sources at six wave bands from 350 to 2000 μm and derived upper limits for their far-infrared (FIR) emission from the IRAS raw data. The millimeter/submillimeter emission originates from cold dust (Td ~ 20 K), and the individual components have gas masses of 5 M☉ < Mgas < 36 M☉. The ratio Lbol/Lsmm is below 70 for six sources associated with OMC-3, indicating that they are class 0-type objects. Condensations in the OMC-2 region have Lbol/Lsmm ≤ 360, suggesting an evolutionary effect from north to south. We report the discovery of a highly collimated bipolar CO outflow, most likely driven by the source OMC-3 MMS 8. The flow is over 5' (0.7 pc) long and less than 1' (0.15 pc) wide and is oriented nearly east-west. Less prominent outflows are associated with OMC-2 FIR 2/3 and OMC-3 MMS 6. The 1300 μm continuum emission is confined to a ridge less than 1' wide while the emission in J = 2-113CO, C18O, and CS is between 5' and 10' wide. The continuum emission is displaced toward the eastern side of the molecular ridge that contains it. Most 1300 μm sources lie in or close to line emission peaks. However, not all line emission peaks contain prominent 1300 μm continuum sources. The curved filamentary structure of the large-scale dust and molecular emission is likely the result of compression by the superbubble centered ~25-70 pc further north, plus the impact of energy from the younger 1c subgroup of the Orion OB association, which lies 10-50 pc in front of our mapped region, and by the very recent expansion of the NGC 1977 and M42 H II regions.

Discovery of a molecular hydrogen jet near IC 348

view Abstract Citations (162) References (36) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Discovery of a Molecular Hydrogen Jet near IC 348 McCaughrean, Mark J. ; Rayner, John T. ; Zinnecker, Hans Abstract We present near-infrared images of a newly discovered molecular hydrogen jet (HH 211) near the young stellar cluster IC 348 in the Perseus dark cloud complex. A wide-field true-color JHK' image locates HH 211 relative to the embedded source IC 348 IR, and a high-resolution image taken in the H2 upsilon = 1 - 0 S(1) line at 2.122 micrometers delineates the shock-excited gas. The jet is very young, with a dynamical age of less than 1000 yr. We suggest that the H2 emission arises in a turbulent sheath around the true jet, leading to an unusual symmetric limb-brightened appearance. This boundary layer is probably where ambient molecular material is being entrained to form a coincident bipolar CO outflow. We discuss possible models for the knots in HH 211, including internal working surfaces in an episodic outflow and crossing shocks in a recollimating jet. The exciting source of the jet and outflow was detected at lambda greater than or = 350 micrometers, and our observations imply that the exciting source is a young star deeply embedded in a dense NH3 core, perhaps an edge-on circumstellar disk. The HH 211 system of jet, molecular outflow, and embedded exciting source is the first discovered through near-infrared imaging. Publication: The Astrophysical Journal Pub Date: December 1994 DOI: 10.1086/187664 Bibcode: 1994ApJ...436L.189M Keywords: Hydrogen; Interstellar Gas; Jet Flow; Molecular Clouds; Molecular Flow; Star Clusters; Star Formation; Stellar Envelopes; Rosat Mission; Stellar Luminosity; Astrophysics; STARS: CIRCUMSTELLAR MATTER; INFRARED: ISM: CONTINUUM; INFRARED: ISM: LINES AND BANDS; ISM: JETS AND OUTFLOWS; ISM: MOLECULES; STARS: FORMATION full text sources ADS | data products SIMBAD (39)

The outflow in the L1157 dark cloud - Evidence for shock heating of the interacting gas

view Abstract Citations (95) References (19) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Outflow in the L1157 Dark Cloud: Evidence for Shock Heating of the Interacting Gas Umemoto, T. ; Iwata, T. ; Fukui, Y. ; Mikami, H. ; Yamamoto, S. ; Kameya, O. ; Hirano, N. Abstract In the L1157 dark cloud, a well-collimated bipolar CO outflow associated with a cold IRAS source 20386 + 6751 was discovered. The gas temperature toward the blue lobe of the outflow rises to about 30 K from the temperature of the surrounding gas (not greater than 10 K); this high temperature region is very localized within the blue lobe. The HCO(+), HCN, and NH3 lines show blueshifted and broad-line profiles toward the blue CO lobe. Furthermore, their distributions are similar to that of the blue lobe. Analysis of the energy of the outflow and dense gas suggests that a strong shock caused by the outflow is responsible for the temperature enhancement. Such shock heating has rarely been observed in low-mass star-forming regions. These data show that the outflow has an influence on the thermal properties of the parent cloud at least locally through shock processes in its early evolutionary stage. Publication: The Astrophysical Journal Pub Date: June 1992 DOI: 10.1086/186431 Bibcode: 1992ApJ...392L..83U Keywords: Gas Flow; Infrared Astronomy Satellite; Interstellar Matter; Shock Wave Interaction; Star Formation; Stellar Composition; Ammonia; Carbon Monoxide; Formyl Ions; Hydrocyanic Acid; Shock Heating; Astrophysics; ISM: MOLECULES; ISM: INDIVIDUAL ALPHANUMERIC: L1157; ISM: JETS AND OUTFLOWS; STARS: FORMATION; SHOCK WAVES full text sources ADS | data products SIMBAD (2)