We study the large-scale magnetic field structure and its interplay with the gas dynamics in the Monoceros OB1 East molecular cloud. We combine observations of dust polarised emission from the Planck telescope and CO molecular line emission observations from the Taeduk Radio Astronomy Observatory 14-metre telescope. We calculate the strength of the plane-of-the-sky magnetic field using a modified Chandrasekhar-Fermi method and estimate mass over flux ratios in different regions of the cloud. We use the comparison of the velocity and intensity gradients of the molecular line observations with the polarimetric observations to trace dynamically active regions. The molecular complex shows an ordered large-scale plane-of-the-sky magnetic field structure. In the Northern part, it is mostly orientated along the filamentary structures while the Southern part shows at least two regions with distinct magnetic field orientations. We find that in the Northern filaments the magnetic field is unlikely to provide support against fragmentation at large scales. Our analysis reveals a shock region in the Northern part of the complex right in-between two filamentary clouds which were previously suggested to be in collision. Moreover, the shock seems to extend farther towards the Western part of the complex. In the Southern part, we find that either the magnetic field guides the accretion of interstellar matter towards the cloud or it was dragged by the matter towards the densest regions. The large-scale magnetic field in Monoceros OB-1 East molecular clouds is tightly connected to the global structure of the complex and, in the Northern part, it seems to be dominated by gravity and turbulence, while in the Southern part it influences the structuring of matter.
We study the kinematic properties of the Eastern Banded Structure (EBS) and Hydra I overdensity using exquisite proper motions derived from the Sloan Digital Sky Survey (SDSS) and Gaia source catalog. Main sequence turn-off stars in the vicinity of the EBS are identified from SDSS photometry; we use the proper motions and, where applicable, spectroscopic measurements of these stars to probe the kinematics of this apparent stream. We find that the EBS and Hydra I share common kinematic and chemical properties with the nearby Monoceros Ring. In particular, the proper motions of the EBS, like Mon…
We started a multi-scale analysis of G202.3+2.5, an intertwined filamentary region of Monoceros OB1. In Paper I, we examined the distributions of dense cores and protostars and found enhanced star formation (SF) activity in the junction region of the filaments. In this second paper, we aim to unveil the connections between the core and filament evolutions, and between the filament dynamics and the global evolution of the cloud. We characterise the gas dynamics and energy balance using Herschel and WISE observations and molecular tracers observed with the IRAM 30m and TRAO 14m telescopes. The v…
Context. V838 Mon is an eruptive variable, which exploded in 2002. It displayed the most spectacular light echo ever observed. However, neither the origin of the reflecting matter nor the nature of the 2002 outburst have been firmly constrained. Aims. We investigate the nature of the CO radio emission detected in the field of the light echo. In particular, we explore its connection to the echoing dust around V838 Mon. Methods. We observed the echo region in multiple CO rotational transitions. We present and analyse maps of the region obtained in the 12CO(1-0) and (3-2) lines. In addition, deep…
Current theories and models attempt to explain star formation globally, from core scales to giant molecular cloud scales. A multi-scale observational characterisation of an entire molecular complex is necessary to constrain them. We investigate star formation in G202.3+2.5, a ~10x3 pc sub-region of the Monoceros OB1 cloud with a complex morphology harbouring interconnected filamentary structures. We aim to connect the evolution of cores and filaments in G202.3+2.5 with the global evolution of the cloud and to identify the engines of the cloud dynamics. In this first paper, the star formation a…
We present a generalization of the Giant Molecular Cloud (GMC) identification problem based on cluster analysis. The method we designed, SCIMES (Spectral Clustering for Interstellar Molecular Emission Segmentation) considers the dendrogram of emission in the broader framework of graph theory and utilizes spectral clustering to find discrete regions with similar emission properties. For Galactic molecular cloud structures, we show that the characteristic volume and/or integrated CO luminosity are useful criteria to define the clustering, yielding emission structures that closely reproduce "by-e…
We use Gaia DR2 data to survey the classic Monoceros OB1 region and look for the existence of a dispersed young population, co-moving with the cloud complex. An analysis of the distribution of proper motions reveals a 20-30 Myr association of young stars, about 300-400 pc away from the far side of the Mon OB1 complex, along the same general line-of-sight. We characterize the new association, Monoceros OB4, and estimate it contains between 1400 and 2500 stars, assuming a standard IMF, putting it on par in size with NGC\,2264. We find from the internal proper motions that Mon OB4 is unbound and …
Microquasar SS 433 located at the geometric center of radio nebula W50 is a suitable source for investigating the physical process of how galactic jets affect the surrounding interstellar medium (ISM). Previous studies have searched for evidence of the interaction between the SS 433 jet and ISM, such as neutral hydrogen gas and molecular clouds; however, it is still unclear which ISM interacts with the jet. We looked for new molecular clouds that possibly interact at the terminal of the SS 433 eastern jet using the Nobeyama 45-m telescope and the Atacama Submillimeter Telescope Experiment (AST…
The origin of the Galactic Anticenter Stellar Structure (GASS) or "Monoceros ring" --- a low latitude overdensity at the edge of the Galactic disk spanning at least the second and third Galactic quadrants --- remains controversial. Models for the origin of GASS fall generally into scenarios where it is either a part (e.g., warp) of the Galactic disk or it represents tidal debris from the disruption of a Milky Way (MW) satellite galaxy. To further constrain models for the origin of GASS, we derive chemical abundance patterns from high resolution spectra for 21 M giants spatially and kinematical…
We present a 1.1~mm census of dense cores in the Mon~R2 Giant Molecular Cloud with the AzTEC instrument on the Large Millimeter Telescope (LMT). We detect 295 cores (209 starless, and 86 with protostars) in a two square degree shallow survey. We also carry out a deep follow-up survey of 9 regions with low to intermediate ($3<A_V<7$) gas column densities and detect 60 new cores in the deeper survey which allows us to derive a completeness limit. After performing corrections for low signal-to-noise cores, we find a median core mass of $\sim 2.1 \text{M}_{\odot}$ and a median size of $ 0.08$~pc. …
We present the first detailed analysis of the East Cloud, a highly disrupted diffuse stellar substructure in the outer halo of M31. The core of the substructure lies at a projected distance of $\sim100$ kpc from the centre of M31 in the outer halo, with possible extensions reaching right into the inner halo. Using Pan-Andromeda Archaeological Survey photometry of red giant branch stars, we measure the distance, metallicity and brightness of the cloud. Using Hubble Space Telescope data, we independently measure the distance and metallicity to the two globular clusters coincident with the East C…
UVIT Study of the MAgellanic Clouds (U-SMAC) I. Recent star formation history and kinematics of the Shell region in the North-Eastern Small Magellanic Cloud
Kinematics of young star clusters in the outer north-eastern region of the Small Magellanic Cloud
Instituto Interdisciplinario de Ciencias Básicas (ICB), CONICET-UNCuyo（基础科学跨研究所）；Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)（国家科学研究委员会）
The astrometric sample of Gaia allows us to study the outermost Galactic disc, the halo and their interface. It is precisely at the very edge of the disc where the effects of external perturbations are expected to be the most noticeable. Our goal is to detect the kinematic substructure present in the halo and at the edge of the Milky Way (MW) disc, and provide observational constraints on their phase-space distribution. We download, one HEALpix at a time, the proper motion histogram of distant stars, to which we apply a Wavelet Transformation to reveal the significant overdensities. We then an…
We present the ALMA Band 3 and Band 6 results of 12CO(2-1), 13$CO(2-1), H30alpha recombination line, free-free emission around 98 GHz, and the dust thermal emission around 230 GHz toward the N159 East Giant Molecular Cloud (N159E) in the Large Magellanic Cloud (LMC). LMC is the nearest active high-mass star forming face-on galaxy at a distance of 50 kpc and is the best target for studing high-mass star formation. ALMA observations show that N159E is the complex of filamentary clouds with the width and length of ~1 pc and 5 pc - 10 pc, respectively. The total molecular mass is 0.92 x 10^5 Msun …
We present far-infrared observations of Monoceros R2 (a giant molecular cloud at approximately 830 pc distance, containing several sites of active star formation), as observed at 70 μm, 160 μm, 250 μm, 350 μm, and 500 μm by the Photodetector Array Camera and Spectrometer (PACS) and Spectral and Photometric Imaging Receiver (SPIRE) instruments on the Herschel Space Observatory as part of the Herschel imaging survey of OB young stellar objects (HOBYS) Key programme. The Herschel data are complemented by SCUBA-2 data in the submillimetre range, and WISE and Spitzer data in the mid-infrared. In ad…
The eastern region of the Small Magellanic Cloud (SMC) is found to have a foreground stellar sub-structure, which is identified as a distance bimodality (12 kpc apart) in the previous studies using Red Clump (RC) stars. Interestingly, studies of Red giant branch (RGB) stars in the eastern SMC indicate a bimodal radial velocity (RV) distribution. In this study, we investigate the connection between these two bimodal distributions to better understand the nature and origin of the foreground stellar sub-structure in the eastern SMC. We use the Gaia EDR3 astrometric data and archival RV data of RG…
We present spectral classifications from optical spectroscopy of 263 massive stars in the north-eastern region of the Large Magellanic Cloud. The observed two-degree field includes the massive 30 Doradus star-forming region, the environs of SN1987A, and a number of star-forming complexes to the south of 30 Dor. These are the first classifications for the majority (203) of the stars and include eleven double-lined spectroscopic binaries. The sample also includes the first examples of early OC-type spectra (AAOmega 30 Dor 248 and 280), distinguished by the weakness of their nitrogen spectra and …
We report on the discovery of a new diffuse stellar sub-structure protruding for 5 degrees from the North-Eastern rim of the LMC disc. The structure, that we dub North-East Structure (NES), was identified by applying a Gaussian Mixture Model to a sample of strictly selected candidate members of the Magellanic System, extracted from the Gaia EDR3 catalogue. The NES fills the gap between the outer LMC disk and other known structures in the same region of the LMC, namely the Northern tidal arm (NTA) and the Eastern sub-structures (ES). Particularly noteworthy is that the NES is placed in a region…
Giant molecular clouds contain supersonic turbulence and magnetohydrodynamic simulations predict that this turbulence should decay rapidly. Such turbulent dissipation has the potential to create a warm (T ~100 K) gas component within a molecular cloud. We present observations of the CO J = 5-4 and 6-5 transitions, taken with the Herschel Space Observatory, towards the Perseus B1-East 5 region. We combine these new observations with archival measurements of lower rotational transitions and fit photodissociation region models to the data. We show that Perseus B1-E5 has an anomalously large CO J …
Distance measurements to molecular clouds are important, but are often made separately for each cloud of interest, employing very different different data and techniques. We present a large, homogeneous catalog of distances to molecular clouds, most of which are of unprecedented accuracy. We determine distances using optical photometry of stars along lines of sight toward these clouds, obtained from PanSTARRS-1. We simultaneously infer the reddenings and distances to these stars, tracking the full probability distribution function using a technique presented in Green et al. (2014). We fit thes…
The dense cloud associated with W40, one of the nearby H II regions, has been studied in millimeter-wave molecular lines and in 1.2 mm continuum. Besides, 1280 MHz and 610 MHz interferometric observations have been done. The cloud has complex morphological and kinematical structure, including a clumpy dust ring and an extended dense core. The ring is probably formed by the "collect and collapse" process due to the expansion of neighboring H II region. Nine dust clumps in the ring have been deconvolved. Their sizes, masses and peak hydrogen column densities are: $\sim 0.02-0.11$ pc, $\sim 0.4-8…
We present the results of a pilot wide-field radial velocity and metal abundance survey of red giants in ten fields in the Small Magellanic Cloud (SMC). The targets lie at projected distances of 0.9 and 1.9 kpc from the SMC centre ($m-M=18.79$) to the North, East, South and West. Two more fields are to the East at distances of 3.9 and 5.1 kpc. In this last field we find only a few to no SMC giants, suggesting that the edge of the SMC in this direction lies approximately at 6 kpc from its centre. In all eastern fields we observe a double peak in the radial velocities of stars, with a component …
We present HI synthesis imaging of the giant elliptical galaxy IC 1459 and its surroundings with the Australia Telescope Compact Array (ATCA). Our search for extended HI emission revealed a large complex of HI clouds near IC 1459, likely the debris from tidal interactions with neighbouring galaxies. The total HI mass ($\sim 10^9$\Msun) in the detected clouds spans 250 kpc from the north-east of the gas-rich spiral NGC 7418A to the south-east of IC 1459. The extent and mass of the HI debris, which shows rather irregular morphology and kinematics, are similar to those in other nearby groups. Tog…
We present a near-infrared extinction map of a large region (approximately 2200 deg^2) covering the Orion, the Monoceros R2, the Rosette, and the Canis Major molecular clouds. We used robust and optimal methods to map the dust column density in the near-infrared (NICER and NICEST) towards ~19 million stars of the Two Micron All Sky Survey (2MASS) point source catalog. Over the relevant regions of the field, we reached a 1-sigma error of 0.03 mag in the K-band extinction with a resolution of 3 arcmin. We measured the cloud distances by comparing the observed density of foreground stars with the…
We present a multi-wavelength data analysis of the extended star-forming region S235 (hereafter E-S235), where two molecular clouds are present. In E-S235, using the 12CO (1-0) and 13CO (1-0) line data, a molecular cloud linked with the site "S235main" is traced in a velocity range [-24, -18] km s^{-1}, while the other one containing the sites S235A, S235B, and S235C (hereafter "S235ABC") is depicted in a velocity range [-18, -13] km s^{-1}. In the velocity space, these two clouds are separated by ~4 km s^{-1}, and are interconnected by a lower intensity intermediate velocity emission, tracing…
A group of four compact HII regions associated with the well-known 50 km/s molecular cloud is the closest site of on-going star formation to the dynamical center of the Galaxy, at a projected distance of ~6 pc. We present a study of ionized gas based on the [NeII] (12.8 micron) line, as well as multi-frequency radio continuum, HST Pa alpha and Spitzer IRAC observations of the most compact member of the HII group, Sgr A East HII D. The radio continuum image at 6cm shows that this source breaks up into two equally bright ionized features, D1 and D2. The SED of the D source is consistent with it …
Sh2-48 is a Galactic HII region located at 3.8 kpc with an O9.5-type star identified at its center. As a part of the FOREST Unbiased Galactic plane Imaging survey using the Nobeyama 45-m telescope (FUGIN) project, we obtained the CO J=1-0 dataset for a large area of Sh2-48 at a spatial resolution of 21"(~0.4 pc), which we used to find a molecular cloud with a total molecular mass of ~3.8x10^4 Mo associated with Sh2-48. The molecular cloud has a systematic velocity shift within a velocity range ~42-47 km/s . On the lower velocity side the CO emission spatially corresponds with the bright 8 μm f…
We study the morphology of the stellar periphery of the Magellanic Clouds in search of substructure using near-infrared imaging data from the VISTA Hemisphere Survey (VHS). Based on the selection of different stellar populations using the ($J-K_\mathrm{s}$, $K_\mathrm{s}$) colour-magnitude diagram, we confirm the presence of substructures related to the interaction history of the Clouds and find new substructures on the easter side of the LMC disc which may be owing to the influence of the Milky Way, and on the northern side of the SMC, which is probably associated to the ellipsoidal structure…
The eastern border of the SNR G18.8+0.3, close to an HII regions complex, is a very interesting region to study the molecular gas that it is probably in contact with the SNR shock front. We observed the aforementioned region using the Atacama Submillimeter Telescope Experiment (ASTE) in the 12CO J=3-2, 13CO J=3-2, HCO+ J=4-3, and CS J=7-6 lines with an angular resolution of 22". To complement these observations, we analyzed IR, submillimeter and radio continuum archival data. In this work, we clearly show that the radio continuum "protrusion" that was early thought to belong to the SNR is an H…
We present N-body simulations of a Sagittarius-like dwarf spheroidal galaxy (Sgr) that follow its orbit about the Milky Way (MW) since its first crossing of the Galaxy's virial radius to the present day. As Sgr orbits around the MW, it excites vertical oscillations, corrugating and flaring the Galactic stellar disc. These responses can be understood by a two-phase picture in which the interaction is first dominated by torques from the wake excited by Sgr in the MW dark halo before transitioning to tides from Sgr's direct impact on the disc at late times. We show for the first time that a massi…
We present results from an analysis of $\sim$ 29,000 RR Lyrae stars located in the Large Magellanic Cloud (LMC). For these objects, near-infrared time-series photometry from the VISTA survey of the Magellanic Clouds system (VMC) and optical data from the OGLE (Optical Gravitational Lensing Experiment) IV survey and the Gaia Data Release 2 catalogue of confirmed RR Lyrae stars were exploited. Using VMC and OGLE IV magnitudes we derived period-luminosity (PL), period-luminosity-metallicity (PLZ), period-Wesenheit (PW) and period-Wesenheit-metallicity (PWZ) relations in all available bands. More …
Context. The central molecular zone at the Galactic center is currently being studied intensively to understand how star formation proceeds under the extreme conditions of a galactic nucleus. Knowing the position of molecular clouds along the line of sight toward the Galactic center has had important implications in our understanding of the physics of the gas and star formation in the central molecular zone.It was recently claimed that the dense molecular cloud G0.253 + 0.016 (the Brick) has a distance of $\sim$7.20 kpc from the Sun. That would place it outside of the central molecular zone, a…
We study the structure and kinematics of the OH-streamer and the +80 km/s cloud and their interactions with the circumnuclear disk (CND) and with other molecular clouds in the vicinity of the Galactic centre (GC), and we map OH absorption at about 6" resolution at R $\le$ 10 pc from the GC, with about 9 km/s velocity resolution. The VLA was used to map OH line absorption at the 1665 and 1667 MHz lambda doublet main lines towards the Sagittarius A complex. Strong OH absorption was found in the OH-streamer, the southern streamer (SS), the +20, +50, and +80 km/s molecular clouds, the molecular be…
The early B star S1 in the Rho Ophiuchus cloud excites an HII region and illuminates a large egg-shaped photodissociation (PDR) cavity. The PDR is restricted to the west and south-west by the dense molecular Rho Oph A ridge, expanding more freely into the diffuse low density cloud to the north-east. We analyze new SOFIA GREAT, GMRT and APEX data together with archival data from Herschel/PACS, JCMT/HARPS to study the properties of the photo-irradiated ionized and neutral gas in this region. The tracers include [C II] at 158 micron, [O I] at 63 and 145 micron, J=6-5 transitions of CO and 13CO, H…
Recent observational studies identified a foreground stellar sub-structure traced by red clump (RC) stars (~ 12 kpc in front of the main body) in the eastern regions of the Small Magellanic Cloud (SMC) and suggested that it formed during the formation of the Magellanic Bridge (MB), due to the tidal interaction of the Magellanic Clouds. Previous studies investigated this feature only up to 4.0 deg from the centre of the SMC due to the limited spatial coverage of the data and hence could not find a physical connection with the MB. To determine the spatial extent and properties of this foreground…
Molecular clouds, which harbor the birthplaces of stars, form out of the atomic phase of the interstellar medium (ISM). We aim to characterize the atomic and molecular phases of the ISM and set their physical properties into the context of cloud formation processes. We studied the cold neutral medium (CNM) by means of $\rm HI$ self-absorption (HISA) toward the giant molecular filament GMF20.0-17.9 and compared our results with molecular gas traced by $^{13}\rm CO$ emission. We fitted baselines of HISA features to $\rm HI$ emission spectra using first and second order polynomial functions. The …
Being one of the most abundant atomic/molecular species observed in dense molecular gas, atomic carbon ($\mathrm{C}^0$) is a potential good tracer of molecular gas mass in many chemical/physical environments, though the $\mathrm{C^0}$ abundance variation outside the Galactic disk region is yet to be fully known. This paper presents a wide-field 500 GHz [CI] map of the Galactic central molecular zone (CMZ) obtained with the ASTE 10-m telescope. Principal component analysis and non-LTE multi-transition analysis have shown that the [CI] emission predominantly originates from the low-excitation ga…
We present results of the $^{12}$CO (1--0) mosaic observations of the nearby barred-spiral galaxy M83 obtained with the Atacama Large Millimeter/submillimeter Array (ALMA). The total flux is recovered by combining the ALMA data with single-dish data obtained using the Nobeyama 45-m telescope. The combined map covers a $\sim$13 kpc$^{2}$ field that includes the galactic center, eastern bar, and spiral arm with a resolution of \timeform{2''.03} $\times$ \timeform{1''.1} ($\sim$45 pc $\times$ $\sim$25 pc). With a resolution comparable to typical sizes of giant molecular clouds (GMCs), the CO dist…
We present ALMA CO(2-1) observations toward a massive infrared dark cloud G28.37+0.07. The ALMA data reveal numerous molecular (CO) outflows with a wide range of sizes throughout the cloud. Sixty-two 1.3 mm continuum cores were identified to be driving molecular outflows. We have determined the position angle in the plane-of-sky of 120 CO outflow lobes and studied their distribution. We find that the distribution of the plane-of-sky outflow position angles peaks at about 100 degree, corresponding to a concentration of outflows with an approximately east-west direction. For most outflows, we ha…
We present the statistical properties of molecular clumps in the Galactic center 50 km s$^{-1}$ molecular cloud (GCM-0.02-0.07) based on observations of the CS $J=1-0$ emission line with the Nobeyama Millimeter Array. In the cloud, 37 molecular clumps with local thermal equilibrium (LTE) masses of $2\times10^2-6\times10^3 M_\odot$ were identified by using the {\it clumpfind} algorithm. The velocity widths of the molecular clumps are about five-fold those of Galactic disk molecular clouds with the same radius. The virial-theorem masses are three-fold the LTE masses. The mass and size spectra ca…
LDN 1157, is one of the several clouds situated in the cloud complex, LDN 1147/1158, represents a coma-shaped morphology with a well-collimated bipolar outflow emanating from a Class 0 protostar, LDN 1157-mm. The main goals of this work are (a) to map the inter-cloud magnetic field (ICMF) geometry of the region surrounding LDN 1157 to investigate its relationship with the cloud morphology, with the outflow direction and with the core magnetic field (CMF) geometry inferred from the mm- and sub-mm polarization results from the literature, and (b) to investigate the kinematic structure of the clo…
The "VISTA near-infrared YJKs survey of the Magellanic System" (VMC) is collecting deep Ks-band time-series photometry of pulsating stars hosted by the two Magellanic Clouds and their connecting Bridge. Here we present YJKs light curves for a sample of 717 Small Magellanic Cloud (SMC) Classical Cepheids (CCs). These data, complemented with our previous results and V magnitude from literature, allowed us to construct a variety of period-luminosity and period-Wesenheit relationships, valid for Fundamental, First and Second Overtone pulsators. These relations provide accurate individual distances…
The dynamical processes that control star formation in molecular clouds are not well understood, and in particular, it is unclear if rotation plays a major role in cloud evolution. We investigate the importance of rotation in cloud evolution by studying the kinematic structure of a spiral-shaped Galactic molecular cloud G052.24+00.74. The cloud belongs to a large filament, and is stretching over ~ 100 pc above the Galactic disk midplane. The spiral-shaped morphology of the cloud suggests that the cloud is rotating. We have analysed the kinematic structure of the cloud, and study the fragmentat…
We investigate the dust associated with the supernova remnant (SNR) N49 in the Large Magellanic Cloud (LMC) as observed with the Herschel Space Observatory. N49 is unusually bright because of an interaction with a molecular cloud along its eastern edge. We have used PACS and SPIRE to measure the far IR flux densities of the entire SNR and of a bright region on the eastern edge of the SNR where the SNR shock is encountering the molecular cloud. Using these fluxes supplemented with archival data at shorter wavelengths, we estimate the dust mass associated with N49 to be about 10 Msun. The bulk o…
Near-infrared (IR) imaging polarimetry in the J, H, and Ks bands has been carried out for the protostellar cluster region around NGC 2264 IRS 2 in the Monoceros OB1 molecular cloud. Various infrared reflection nebulae clusters (IRNCs) associated with NGC 2264 IRS 2 and IRAS 12 S1 core were detected as well as local infrared reflection nebulae (IRNe). The illuminating sources of the IRNe were identified with known or new near- and mid-IR sources. In addition, 314 point-like sources were detected in all three bands and their aperture polarimetry was studied. Using a color-color diagram, reddened…
Molecular clouds form from the atomic phase of the interstellar medium. However, characterizing the transition between the atomic and the molecular interstellar medium (ISM) is a difficult observational task. Here we address cloud formation processes by combining HSIA with molecular line data. One scenario proposed by numerical simulations is that the column density probability density functions (N-PDF) evolves from a log-normal shape at early times to a power-law-like shape at later times. In this paper, we study the cold atomic component of the giant molecular filament GMF38a (d=3.4 kpc, len…
Identifying the young optically visible population in a star-forming region is essential for fully understanding the star formation event. In this paper, We identify 211 candidate members of the Perseus molecular cloud based on Gaia astronomy. We use LAMOST spectra to confirm that 51 of these candidates are new members, bringing the total census of known members to 856. The newly confirmed members are less extincted than previously known members. Two new stellar aggregates are identified in our updated census. With the updated member list, we obtain a statistically significant distance gradien…
The bar of the Large Magellanic Cloud (LMC) is one of the prominent, but controversial feature regarding its location with respect to the disk of the LMC. In order to study the relative location of the bar with respect to the disk, we present the high resolution map of the structure across the LMC. We used the reddening corrected mean magnitudes ($I_0$) of red clump (RC) stars from the OGLE III catalogue to map the relative variation in distance (vertical structure) or variation in RC population across the LMC. The bar does not appear as an identifiable vertical feature in the map, as there is…
Predicting the Radiation Field of Molecular Clouds using Denoising Diffusion Probabilistic Models
University of Virginia（弗吉尼亚大学）；The University of Texas at Austin（德克萨斯大学奥斯汀分校）；Carnegie Observatories（卡内基天文台）；California Institute of Technology（加州理工学院）
