Related papers: The Deuteration Clock for Massive Starless Cores
In a previous paper we introduced a new method for simulating collisional gravitational $N$-body systems with linear time scaling on $N$, based on the Multi-Particle Collision (MPC) approach. This allows us to simulate globular clusters…
Massive stars influence their surroundings through radiation, winds, and supernova explosions far out of proportion to their small numbers. However, the physical processes that initiate and govern the birth of massive stars remain poorly…
The chemical and physical evolution of starless and pre-stellar cores are of paramount importance to understanding the process of star formation. The Taurus Molecular Cloud cores TMC 1-C and TMC 1-CP share similar initial conditions and…
We present a survey of HCO+ (3-2) observations pointed towards dense cores with previous measurements of N(N2D+)/N(N2H+). Of the 26 cores in this survey, five show the spectroscopic signature of outward motion, nine exhibit neither inward…
Observations of atomic or molecular lines can provide important information about the physical state of star forming regions. In order to investigate the line profiles from dynamical collapsing massive star forming regions (MSFRs), we model…
We identify a "supernova rate problem": the measured cosmic core-collapse supernova rate is a factor of ~ 2 smaller (with significance ~ 2 sigma) than that predicted from the measured cosmic massive-star formation rate. The comparison is…
We report ALMA Band 6 continuum observations of 2000 AU resolution toward four massive molecular clouds in the Central Molecular Zone of the Galaxy. To study gas fragmentation, we use the dendrogram method to identify cores as traced by the…
We have recently completed an observing program with the Australia Telescope Compact Array towards massive star formation regions traced by 6.7 GHz methanol maser emission. We found the molecular cores could be separated into groups based…
The present survey represents a continuation of our study of high mass star forming regions in the lines of deuterated molecules, the first results of which were published in Trofimova et al. (2020). This paper presents the results of…
We present new 3-mm continuum and molecular lines observations from the ATOMS survey towards the massive protostellar clump, MM1, located in the filamentary infrared dark cloud (IRDC), G034.43+00.24 (G34). The lines observed are the tracers…
The Infrared Dark Cloud (IRDC) G028.23-00.19 hosts a massive (1,500 Msun), cold (12 K), and 3.6-70 um IR dark clump (MM1) that has the potential to form high-mass stars. We observed this prestellar clump candidate with the SMA (~3.5"…
The ALMA-IMF Large Program provides multi-tracer observations of 15 Galactic massive protoclusters at matched sensitivity and spatial resolution. We focus on the dense gas kinematics of the G353.41 protocluster traced by N$_2$H$^+$ (1$-$0),…
Deep JHKs photometry was obtained towards eight dense molecular cores and J-H vs. H-Ks color-color plots are presented. Our photometry, sensitive to the detection of a 1 solar mass, 1 X 10^6 year old star through approx. 35 - 50 magnitudes…
We consider the conditions required for a cluster core to shrink, by adiabatic accretion of gas from the surrounding cluster, to densities such that stellar collisions are a likely outcome. We show that the maximum densities attained, and…
We have investigated the evolution and distribution of molecules in collapsing prestellar cores via numerical chemical models, adopting the Larson-Penston solution and its delayed analogues to study collapse. Molecular abundances and…
We present a spatially resolved study of stellar populations in 6 galaxies with stellar masses $M_*\sim10^{10}M_\odot$ at $z\sim3.7$ using 14-filter JWST/NIRCam imaging from the JADES and JEMS surveys. The 6 galaxies are visually selected…
Seven isolated, nearby low-mass starless molecular cloud cores have been observed as part of the Herschel key program Earliest Phases of Star formation (EPoS). By applying a ray-tracing technique to the obtained continuum emission and…
We present APEX observations of C17O(2-1), N2H+(3-2), and N2D+(3-2) towards the subfragments inside the prestellar core SMM 6 in Orion B9. We combined these spectral line data with our previous SABOCA 350-{\mu}m dust continuum map of the…
We demonstrate that $\sim10\,\textrm{s}$ after the core-collapse of a massive star, a thermonuclear explosion of the outer shells is possible for some (tuned) initial density and composition profiles, assuming that the neutrinos failed to…
In this work, we study deuterium fractionation in four starless cores in the low-mass star-forming region L1688 in the Ophiuchus molecular cloud. We study how the deuterium fraction ($R_D$) changes with environment, compare deuteration of…