We analyze the hierarchical structure in the Rosette molecular cloud using ^13 CO J = 1–0 data from the Milky Way Imaging Scroll Painting survey with a nonbinary Dendrogram algorithm that allows multiple branches to emerge from parent structures. A total of 588 substructures are identified, including 458 leaves and 130 branches. The physical parameters of the substructures—including peak brightness temperature ( T _peak ), brightness temperature difference ( T _diff ), radius ( R ), mass ( M ), velocity dispersion ( σ _v ), and surface density (Σ)—are characterized. The T _peak and T _diff distributions follow exponential functions with characteristic values above 5 σ _rms . The statistical properties and scaling relations—i.e., the σ _v – R , M – R , and σ _v – R Σ relations—are in general consistent with those from traditional segmentation methods. The mass and radius follow power-law distributions with exponents of 2.2–2.5, with slightly flatter slopes for substructures inside the H ii region. The velocity dispersion scales weakly with radius ( σ _v ∝ R ^0.45±0.03 , r = 0.58) but shows a tighter correlation with the product of surface density and size ( σ _v ∝ (Σ R ) ^0.29±0.01 , r = 0.73). Self-gravitating substructures are found across scales from ∼0.2 to 10 pc, and nearly all structures with peak brightness above 4 K are gravitationally bound ( α _vir < 2). The fraction of bound structures increases with mass, size, and surface density, supporting the scenario of global hierarchical collapse for the evolution of molecular clouds, in which molecular clouds and their substructures are undergoing multiscale collapse.

We present the first data release (DR1) of the Milky Way Imaging Scroll Painting (MWISP) survey, a mapping in the J = 1 -> 0 transition lines of 12CO, 13CO, and C18O toward the northern Galactic plane during 2011-2022. The MWISP survey was conducted using the Purple Mountain Observatory 13.7 m telescope at a spatial resolution of approximately 50 '' and a velocity resolution of 0.16 km s-1 at 115 GHz. DR1 fully covered 2310 deg2 within the Galactic longitude (l) and latitude (b) range of 9 .degrees 75 <= l <= 229 .degrees 75 and divided by b divided by <= 5 .degrees 25. The surveyed area was divided into cell units of 30 ' x30 ' for practical purposes and on-the-fly mapping was performed toward each target cell unit. The data were regridded into a regular three-dimensional data cube in l-b-VLSR with a pixel size of 30 '' in l-b axes and 0.16 km s-1 in the VLSR axis. The median rms noise is 0.47, 0.25, and 0.25 K for 12CO, 13CO, and C18O, respectively. The equivalent 3 sigma sensitivity in 12CO luminosity is approximately 0.23 K km s-1, making MWISP the most sensitive survey of its kind. In this paper, we describe the survey data, including the calibration, data cleaning, data mosaic processes, and the data products. The final mosaicked data cubes contain about 3.33 x 107 spectra (pixels) for each CO isotopologue line. Color composite images, made from the intensities of the isotopologue lines, and some concise descriptions are provided. We constructed a molecular cloud catalog based on the mosaicked 12CO data cube using the clustering algorithm DBSCAN, detecting 103,517 molecular clouds, 10,790 of which exhibit 13CO emission and 304 of which show C18O emission. Based on the histogram of voxel brightness temperature, we estimated a total 12CO flux of 7.69 +/- 0.38 x 107 K km s-1 arcmin2, 82% of which is captured by the DBSCAN algorithm. The properties of molecular clouds show a large dynamic range, facilitating more accurate statistics. The data, together with the cloud sample, provide unique information on molecular gas in the northern Milky Way.

Feedback from massive stars regulates the formation of next-generation stars and planets and thus shapes the evolution of galaxies, yet observational evidence capable of determining which mechanism dominates the feedback process has long been lacking. Here, we present a large-scale H I survey toward Orion A. With an unprecedented sensitivity and superior resolution, FAST (Five-hundred-meter Aperture Spherical radio Telescope) reveals a well-defined heart-shaped expanding H I bubble, enshrouding the well-known “Veil” bubble of ionized gas. The photoionization-driven and wind-driven gas expands at 10.9 and 13.8 kilometers per second, respectively, with a kinetic energy ratio of 1:2 assuming a spherical symmetry and a uniform H I -to-H 2 ratio. This first direct comparison within a single bubble shows that radiation does not dominate the feedback process as predicted by classical theories; instead, stellar winds contribute a comparable share of the injected kinetic energy.

We use ^12CO (J=1–0) data from the MWISP survey to investigate turbulence in a ∼kpc-scale segment of the Local Arm. By slicing the position-position-velocity cube into narrow layers that follow the Galactic-rotation trend in the L-V diagram, we find that the structure functions (SFs) and spatial power spectra (SPS) of the ^12CO (J=1–0) line velocity and intensity exhibit consistent scaling behaviors across all layers, demonstrating that the molecular gas forms a single, coherent turbulent field with energy cascading from ∼ 200 pc down to parsec scales. The SPS power-law slopes of both the intensity and velocity fields approach the values expected from turbulence models. Cloud-to-cloud velocity SFs based on the molecular clouds located in the region follow the same extended self-similarity scaling (ESS) as the pixel-based statistics, indicating that inter-cloud motions are part of the same large-scale turbulent cascade. Together, these results provide direct observational evidence that molecular clouds are not dynamically isolated entities but are embedded within a larger-scale turbulent flow that links galactic dynamics to star formation on cloud scales.

Dust grains in protoplanetary disks are the building blocks of planets. Investigating the dust composition and size, and their variation over time, is crucial for understanding the planet formation process. The PDS 70 disk is so far the only protoplanetary disk with concrete evidence for the presence of young planets. Mid-infrared spectra were obtained for PDS 70 by the Infrared Spectrograph (IRS) on the Spitzer Space Telescope (SST) and the Mid-Infrared Instrument (MIRI) on the James Webb Space Telescope (JWST) in 2007 and 2022, respectively. In this work, we investigate the dust mineralogy through a detailed decomposition of the observed mid-infrared spectra. The results show that both the dust size and crystallinity increased by a factor of about two during the two epochs of observation, indicating evident dust processing in the terrestrial planet-forming region of the PDS 70 disk. The dust size (∼ 0.8 µm) and crystallinity (∼ 6

We present a systematic analysis of the velocity structure functions (VSFs) of 167 molecular clouds with angular sizes greater than $\sim$176 arcmin$^2$ in three sectors of the Galactic mid-plane. We calculated the 1st- to 3rd-order VSFs and found that 60\% of the VSFs exhibit power-law distributions. The relative power-law exponents are consistent with predictions from intermittent turbulence models. Column density weighting reduces the proportion of power-law VSFs and steepens the VSF slopes, implying a reduction of turbulent energy in high-density regions. All clouds show small-scale intermittency, with slightly stronger intermittency in those molecular clouds showing none power-law VSFs. Negative VSF exponents that may indicate gravitational collapse are not observed in our sample. The scaling exponents of the observed VSFs do not correlate with the virial parameters of the molecular clouds. These two observations suggest that gravity-dominated scales in molecular clouds still need further investigation. Consistent VSF scaling exponents for the molecular clouds with significant power-law VSFs suggest large-scale external driving of turbulence in these molecular clouds. However, the driving mechanisms are likely not universal, as the power-law scaling coefficients in our results show relatively large scatter. The fact that nearly 40\% of the VSFs deviate to some extent from power-law distributions suggests that the influence of local environments on the internal turbulence of molecular clouds may not be negligible.

From observations, column density ratios or integrated intensity ratios between some species exhibit monotonic increase or decrease along with the evolution of high-mass star-forming regions (HMSFRs). Such ratios are defined as chemical clocks, which can be used to constrain the evolutionary stage. We performed chemical simulations to reproduce the observed column density ratio of HC3N/N2H+ and the abundances of these two species across various evolutionary stages in HMSFRs. Simultaneously, we identified the chemical processes responsible for the observed time-dependent trends in these stages. Our simulations utilized the astrochemical code Nautilus and the existing 1D models of HMSFRs that cover four evolutionary stages, accompanied by variations in density and temperature throughout the entire evolution. When averaging over large spatial scales, the best model produced successfully matches the observed column density ratio of HC3N/N2H+ and the abundances of the species involved at specific times for each evolutionary stage; that is, the late high-mass starless core stage, the early high-mass protostellar object stage, and the early ultracompact HII stage. HC3N is mainly affected by the warm carbon-chain chemistry (WCCC) and its own thermal desorption, while N2H+ is primarily influenced by the thermal desorption of N2, CO, CH4, NH3, and H2O followed by dissociative recombination and ion-molecule reactions. The results obtained from the best-fitting model timescales broadly agree with statistical estimates. Based on our best-fit model, we further examined other 350 ratios involving 27 species, and 178 ratios exhibit an increasing or decreasing evolutionary trend around the best-fit timescales of HC3N/N2H+. Among them, 157 ratios are observable and could be considered as candidate chemical clocks.

We report 850 $\mu$m continuum polarization observations toward the filamentary high-mass star-forming region NGC 2264, taken as part of the B-fields In STar forming Regions Observations (BISTRO) large program on the James Clerk Maxwell Telescope (JCMT). These data reveal a well-structured non-uniform magnetic field in the NGC 2264C and 2264D regions with a prevailing orientation around 30 deg from north to east. Field strengths estimates and a virial analysis for the major clumps indicate that NGC 2264C is globally dominated by gravity while in 2264D magnetic, gravitational, and kinetic energies are roughly balanced. We present an analysis scheme that utilizes the locally resolved magnetic field structures, together with the locally measured gravitational vector field and the extracted filamentary network. From this, we infer statistical trends showing that this network consists of two main groups of filaments oriented approximately perpendicular to one another. Additionally, gravity shows one dominating converging direction that is roughly perpendicular to one of the filament orientations, which is suggestive of mass accretion along this direction. Beyond these statistical trends, we identify two types of filaments. The type-I filament is perpendicular to the magnetic field with local gravity transitioning from parallel to perpendicular to the magnetic field from the outside to the filament ridge. The type-II filament is parallel to the magnetic field and local gravity. We interpret these two types of filaments as originating from the competition between radial collapsing, driven by filament self-gravity, and the longitudinal collapsing, driven by the region's global gravity.

In this work, we present the data from the Milky Way Imaging Scroll Painting (MWISP) project for the Maddalena giant molecular cloud (GMC). We decompose the 13CO emission datacube of the observed region into hierarchical substructures using a modified Dendrogram algorithm. We investigate the statistical properties of these substructures and examine the role that self-gravity plays on various spatial scales. The statistics of the mass (M), radius (R), velocity dispersion ({\sigma}v), virial parameter ({\alpha}vir), and sonic Mach number of the substructures are presented. The radius and mass distributions and the {\sigma}v-R scaling relationship of the substructures resemble those reported in previous studies that use non-hierarchical algorithms to identify the entities. We find that for the hierarchical substructures {\alpha}vir decreases as the radius or mass of the substructures increases. The majority of the substructures in the quiescent region of Maddalena GMC are not gravitationally bound ({\alpha}vir > 2), while most of the substructures in the star-forming regions are gravitationally bound ({\alpha}vir < 2). Furthermore, we find that self-gravity plays an important role on scales of 0.8-4 pc in the IRAS 06453 star-forming region, while it is not an important factor on scales below 5 pc in the non-star-forming region.

Velocity fields of molecular clouds (MCs) can provide crucial information on the merger and split between clouds, as well as their internal kinematics and maintenance, energy injection and redistribution, and even star formation within clouds. Using the CO spectral lines data from the Milky Way Imaging Scroll Painting survey, we measure the relative velocities along the line of sight (Delta V-LOS) between (CO)-C-13 structures within (CO)-C-12 MCs. Emphasizing MCs with double and triple (CO)-C-13 structures, we find that approximately 70% of Delta V-LOS values are less than similar to 1 km s(-1), and roughly 10% of values exceed 2 km s(-1), with a maximum of similar to 5 km s(-1). Additionally, we compare Delta V-LOS with the internal velocity dispersion of (CO)-C-13 structures (sigma(13CO,in)) and find that about 40% of samples in either double or triple regime display distinct velocity discontinuities, i.e., the relative velocities between (CO)-C-13 structures are larger than the internal line widths of (CO)-C-13 structures. Among these 40% samples in the triple regime, 33% exhibit signatures of combinations through the two-body motion, whereas the remaining 7% show features of configurations through the multiple-body motion. The Delta V-LOS distributions for MCs with double and triple (CO)-C-13 structures are similar, as well as their Delta V-LOS/sigma(13CO,in) distributions. This suggests that relative motions of (CO)-C-13 structures within MCs are random and independent of cloud complexities and scales.

As part of the B-fields In Star-forming Region Observations survey, we present James Clerk Maxwell Telescope (JCMT) 850 mu m polarimetric observations toward the Orion integral-shaped filament (ISF) that covers three portions known as OMC-1, OMC-2, and OMC-3. The magnetic field threading the ISF seen in the JCMT POL-2 map appears as a tale of three: pinched for OMC-1, twisted for OMC-2, and nearly uniform for OMC-3. A multiscale analysis shows that the magnetic field structure in OMC-3 is very consistent at all the scales, whereas the field structure in OMC-2 shows no correlation across different scales. In OMC-1, the field retains its mean orientation from large to small scales but shows some deviations at small scales. Histograms of relative orientations between the magnetic field and filaments reveal a bimodal distribution for OMC-1, a relatively random distribution for OMC-2, and a distribution with a predominant peak at 90 degrees for OMC-3. Furthermore, the magnetic fields in OMC-1 and OMC-3 both appear to be aligned perpendicular to the fibers, which are denser structures within the filament, but the field in OMC-2 is aligned along with the fibers. All these suggest that gravity, turbulence, and magnetic field are each playing a leading role in OMC-1, 2, and 3, respectively. While OMC-2 and 3 have almost the same gas mass, density, and nonthermal velocity dispersion, there are on average younger and fewer young stellar objects in OMC-3, providing evidence that a stronger magnetic field will induce slower and less efficient star formation in molecular clouds.

We perform a comprehensive CO study toward the Monoceros OB1 (Mon OB1) region based on the Milky Way Imaging Scroll Painting survey at an angular resolution of about 50 ''. The high-sensitivity data, together with the high dynamic range, show that molecular gas in the 8 degrees x 4 degrees region displays complicated hierarchical structures and various morphology (e.g., filamentary, cavity-like, shell-like, and other irregular structures). Based on Gaussian decomposition and clustering for 13CO data, a total of 263 13CO structures are identified in the whole region, and 88% of raw data flux is recovered. The dense gas with relatively high column density from the integrated CO emission is mainly concentrated in the region where multiple 13CO structures are overlapped. Combining the results of 32 large 13CO structures with distances from Gaia DR3, we estimate an average distance of 729 - 45 + 45 pc for the giant molecular cloud (GMC) complex. The total mass of the GMC complex traced by 12CO, 13CO, and C18O is 1.1 x 105 M circle dot, 4.3 x 104 M circle dot, and 8.4 x 103 M circle dot, respectively. The dense gas fraction shows a clear difference between Mon OB1 GMC East (12.4%) and Mon OB1 GMC West (3.3%). Our results show that the dense gas environment is closely linked to the nearby star-forming regions. On the other hand, star-forming activities have a great influence on the physical properties of the surrounding molecular gas (larger velocity dispersion, higher temperatures, more complex velocity structures, etc.). We also discuss the distribution/kinematics of molecular gas associated with nearby star-forming activities.

Based on 32162 molecular clouds from the Milky Way Imaging Scroll Painting project, we obtain new face-on molecular gas maps of the northern outer Galaxy. The total molecular gas surface density map reveals three segments of spirals, extending 16-43 kiloparsecs in length. The Perseus and Outer arms stand out prominently, appearing as quasi-continuous structures along most of their length. At the Galactic outskirts, about 1306 clouds connect the two segments of the new spiral arm discovered by Dame & Thaddeus (2011) in the first quadrant and Sun et al. (2015) in the second quadrant, possibly extending the arm into the outer third quadrant. Logarithmic spirals can be fitted to the CO arm segments with pitch angles ranging from 4 to 12 degree. These CO arms extend beyond previous CO studies and the optical radius, reaching a galactic radius of about 22 kiloparsecs, comparable to the HI radial range.

In this work, we present data from the Milky Way Imaging Scroll Painting project for the Maddalena giant molecular cloud (GMC). We decompose the ^13 CO emission datacube of the observed region into hierarchical substructures using a modified dendrogram algorithm. We investigate the statistical properties of these substructures and examine the role that self-gravity plays on various spatial scales. The statistics of the mass ( M ), radius ( R ), velocity dispersion ( σ _v ), virial parameter ( α _vir ), and sonic Mach number of the substructures are presented. The radius and mass distributions and the σ _v –R scaling relationship of the substructures resemble those reported in previous studies that use nonhierarchical algorithms to identify the entities. We find that for the hierarchical substructures α _vir decreases as the radius or mass of the substructures increases. The majority of the substructures in the quiescent region of the Maddalena GMC are not gravitationally bound ( α _vir > 2), while most of the substructures in the star-forming regions are gravitationally bound ( α _vir < 2). Furthermore, we find that self-gravity plays an important role on scales of 0.8–4 pc in the IRAS 06453 star-forming region, while it is not an important factor on scales below 5 pc in the non-star-forming region.

Velocity fields of molecular clouds (MCs) can provide crucial information on the merger and split between clouds, as well as their internal kinematics and maintenance, energy injection and redistribution, even star formation within clouds. Using the CO spectral lines data from the Milky Way Imaging Scroll Painting (MWISP) survey, we measure the relative velocities along the line of sight ($\Delta$V$_{\rm LOS}$) between $^{13}$CO structures within $^{12}$CO MCs. Emphasizing MCs with double and triple $^{13}$CO structures, we find that approximately 70$\%$ of $\Delta$V$_{\rm LOS}$ values are less than $\sim$ 1 km s$^{-1}$, and roughly 10$\%$ of values exceed 2 km s$^{-1}$, with a maximum of $\sim$ 5 km s$^{-1}$. Additionally, we compare $\Delta$V$_{\rm LOS}$ with the internal velocity dispersion of $^{13}$CO structures ($\sigma_{\rm ^{13}CO,in}$) and find that about 40$\%$ of samples in either double or triple regime display distinct velocity discontinuities, i.e. the relative velocities between $^{13}$CO structures are larger than the internal linewidths of $^{13}$CO structures. Among these 40$\%$ samples in the triple regime, 33$\%$ exhibit signatures of combinations through the two-body motion, whereas the remaining 7$\%$ show features of configurations through the multiple-body motion. The $\Delta$V$_{\rm LOS}$ distributions for MCs with double and triple $^{13}$CO structures are similar, as well as their $\Delta$V$_{\rm LOS}$/$\sigma_{\rm ^{13}CO,in}$ distributions. This suggests that relative motions of $^{13}$CO structures within MCs are random and independent of cloud complexities and scales.

We perform a comprehensive CO study toward the Monoceros OB1 (Mon OB1) region based on the MWISP survey at an angular resolution of about $50''$. The high-sensitivity data, together with the high dynamic range, shows that molecular gas in the $\rm 8^{\circ}\times4^{\circ}$ region displays complicated hierarchical structures and various morphology (e.g., filamentary, cavity-like, shell-like, and other irregular structures). Based on Gaussian decomposition and clustering for $\mathrm{^{13}CO}$ data, a total of 263 $\mathrm{^{13}CO}$ structures are identified in the whole region, and 88\% of raw data flux is recovered. The dense gas with relatively high column density from the integrated CO emission is mainly concentrated in the region where multiple $\rm ^{13}CO$ structures are overlapped. Combining the results of 32 large $\mathrm{^{13}CO}$ structures with distances from Gaia DR3, we estimate an average distance of $\rm 729^{+45}_{-45}~pc$ for the GMC complex. The total mass of the GMC Complex traced by $\mathrm{^{12}CO}$, $\mathrm{^{13}CO}$, and $\mathrm{C^{18}O}$ are $1.1\times10^5~M_\odot$, $4.3\times10^4~M_\odot$, and $8.4\times10^3~M_\odot$, respectively. The dense gas fraction shows a clear difference between Mon OB1 GMC East (12.4\%) and Mon OB1 GMC West (3.3\%). Our results show that the dense gas environment is closely linked to the nearby star-forming regions. On the other hand, star-forming activities have a great influence on the physical properties of the surrounding molecular gas (e.g., greater velocity dispersion, higher temperatures, and more complex velocity structures, etc.). We also discuss the distribution/kinematics of molecular gas associated with nearby star-forming activities.

Atacama Large Millimeter/submillimeter Array surveys have suggested that protoplanetary disks are not massive enough to form the known exoplanet population, based on the assumption that the millimeter continuum emission is optically thin. In this work, we investigate how the mass determination is influenced when the porosity of dust grains is considered in radiative transfer models. The results show that disks with porous dust opacities yield similar dust temperatures, but systematically lower millimeter fluxes, as compared to disks that incorporate compact dust grains. Moreover, we have recalibrated the relation between dust temperature and stellar luminosity for a wide range of stellar parameters. We also calculated the dust masses of a large sample of disks using the traditionally analytic approach. The median dust mass from our calculation is about six times higher than the literature result, and this is mostly driven by the different opacities of porous and compact grains. A comparison of the cumulative distribution function between disk dust masses and exoplanet masses shows that the median exoplanet mass is about two times lower than the median dust mass when grains are assumed to be porous and there are no exoplanetary systems with masses higher than the most massive disks. Our analysis suggests that adopting porous dust opacities may alleviate the mass budget problem for planet formation. As an example illustrating the combined effects of optical depth and porous dust opacities on the mass estimation, we conducted new IRAM/NIKA-2 observations toward the IRAS 04370+2559 disk and performed a detailed radiative transfer modeling of the spectral energy distribution (SED). The best-fit dust mass is roughly 100 times higher than the value given by a traditionally analytic calculation. Future spatially resolved observations at various wavelengths are required to better constrain the dust mass.

We present 850 mu m polarization observations of the IC 348 star-forming region in the Perseus molecular cloud as part of the B-fields In STar-forming Region Observation survey. We study the magnetic properties of two cores (HH 211 MMS and IC 348 MMS) and a filamentary structure of IC 348. We find that the overall field tends to be more perpendicular than parallel to the filamentary structure of the region. The polarization fraction decreases with intensity, and we estimate the trend by power law and the mean of the Rice distribution fittings. The power indices for the cores are much smaller than 1, indicative of possible grain growth to micron size in the cores. We also measure the magnetic field strengths of the two cores and the filamentary area separately by applying the Davis-Chandrasekhar-Fermi method and its alternative version for compressed medium. The estimated mass-to-flux ratios are 0.45-2.20 and 0.63-2.76 for HH 211 MMS and IC 348 MMS, respectively, while the ratios for the filament are 0.33-1.50. This result may suggest that the transition from subcritical to supercritical conditions occurs at the core scale (similar to 0.05 pc) in the region. In addition, we study the energy balance of the cores and find that the relative strength of turbulence to the magnetic field tends to be stronger for IC 348 MMS than for HH 211 MMS. The result could potentially explain the different configurations inside the two cores: a single protostellar system in HH 211 MMS and multiple protostars in IC 348 MMS.

Context. Investigating the dust grain size and its dependence on substructures in protoplanetary disks is a crucial step in understanding the initial process of planet formation. Spectral indices derived from millimeter observations are used as a common probe for grain size. Converting observed spectral indices into grain sizes is a complex task that involves solving the radiative transfer equation, taking into account the disk structure and dust properties. Aims. Under the assumption of vertically isothermal disks, the solution to the radiative transfer equation can be approximated with an analytic expression, with which the fitting procedure can be done very fast. Our work aims to investigate the applicability of this method to grain size retrieval. Methods. We ran reference radiative transfer models with known disk properties, and generated four synthetic images at wavelengths of 0.8, 1.3, 3, and 7.8 mm, representing high-resolution continuum observations. Rings and gaps were considered in the setup. We fit the synthetic images using the analytic solution to investigate the circumstances under which the input grain sizes can be recovered. Results. Fitting images at only two wavelengths is not sufficient to retrieve the grain size. Fitting three images improves the retrieval of grain size, but the dust surface density is still not well recovered. When taking all of the four images into account, degeneracies between different parameters are highly reduced, and consequently the best-fit grain sizes are consistent with the reference setup at almost all radii. We find that the inclination angle has a significant impact on the fitting results. For disks with low inclinations, the analytic approach works quite well. However, when the disk is tilted above similar to 60 degrees, neither the grain size nor the dust surface density can be constrained, as the inclination effect will smooth out all substructures in the radial intensity profile of the disk.

We study the H ii regions associated with the NGC 6334 molecular cloud observed in the submillimeter and taken as part of the B -fields In STar-forming Region Observations Survey. In particular, we investigate the polarization patterns and magnetic field morphologies associated with these H ii regions. Through polarization pattern and pressure calculation analyses, several of these bubbles indicate that the gas and magnetic field lines have been pushed away from the bubble, toward an almost tangential (to the bubble) magnetic field morphology. In the densest part of NGC 6334, where the magnetic field morphology is similar to an hourglass, the polarization observations do not exhibit observable impact from H ii regions. We detect two nested radial polarization patterns in a bubble to the south of NGC 6334 that correspond to the previously observed bipolar structure in this bubble. Finally, using the results of this study, we present steps (incorporating computer vision; circular Hough transform) that can be used in future studies to identify bubbles that have physically impacted magnetic field lines.