Related papers: Angular Momentum of the N2H+ Cores in the Orion A …

We present high-angular-resolution ALMA (Atacama Large Millimeter Array) images of N$_{2}$H$^{+}$ (1--0) that has been combined with those from the Nobeyama telescope toward OMC-2 and OMC-3 filamentary regions. The filaments (with typical…

The rotational properties of centrally condensed, turbulent molecular cloud cores with velocity fields that are characterized by Gaussian random fields are investigated. It is shown that the observed line width-size relationship can be…

We investigate the evolution of molecular clouds through the kinematics of their atomic hydrogen (HI) envelopes, using $^{12}\mathrm{CO}$ and 21-cm emission to trace the molecular and atomic gas, respectively. We measure the large-scale…

We have mapped six molecular cloud cores in the Orion A giant molecular cloud (GMC), whose kinetic temperatures range from 10 to 30 K, in CCS and N2H+ with Nobeyama 45 m radio telescope to study their chemical characteristics. We identified…

We present a detailed analysis comparing the velocity fields in molecular clouds and the atomic gas that surrounds them in order to address the origin of the gradients. To that end, we present first-moment intensity-weighted velocity maps…

The ``integral-shaped filament'' of the Orion A giant molecular cloud was mapped in N2H+, and its northern end, the OMC-2/3 region was observed also in HC3N and CCS. The N2H+ distribution is similar to the dust continuum distribution,…

We have analyzed the rotational properties of 12 clumps using $^{13}$CO (1--0) and C$^{18}$O (1--0) maps of the Five College Radio Astronomy Observatory 13.7 m radio telescope. The clumps, located within molecular clouds, have radii ($R$)…

N2H+ observations of molecular cloud cores in Taurus with the Nobeyama 45 m radio telescope are reported. We compare ``cores with young stars'' with ``cores without young stars''. The differences in core radius, linewidth, and core mass are…

We present the results of an interferometric study of the N2H+(1--0) emission from nine nearby, isolated, low-mass protostellar cores, using the OVRO millimeter array. The main goal of this study is the kinematic characterization of the…

Angular momentum is one of the most important physical quantities that govern star formation. The initial angular momentum of a core may be responsible for its fragmentation and can have an influence on the size of the protoplanetary disk.…

In this study, 36 cores (30 starless and 6 protostellar) identified in Orion were surveyed to search for inward motions. We used the Nobeyama 45 m radio telescope, and mapped the cores in the $J = 1\rightarrow0$ transitions of HCO$^+$,…

We have mapped the Orion-A Giant Molecular Cloud in the CO (J=4-3) line with the Tsukuba 30-cm submillimeter telescope.The map covered a 7.125 deg^2 area with a 9' resolution, including main components of the cloud such as Orion Nebula,…

The angular momentum of molecular cloud cores plays an essential role in the star formation process. However, the time evolution of the angular momentum of molecular cloud cores is still unclear. In this paper, we perform three-dimensional…

We present results of an extensive mapping survey of N2H+(1-0) in about 60 low mass cloud cores already mapped in the NH3(1,1) inversion transition line. The survey has been carried out at the FCRAO antenna with an angular resolution about…

We mapped two molecular cloud cores in the Orion A cloud with the ALMA ACA 7-m Array and with the Nobeyama 45-m radio telescope. These cores have bright N$_2$D$^+$ emission in single-pointing observations with the Nobeyama 45-m radio…

We present an analysis comparing the properties of 45 giant molecular clouds (GMCs) in M33 and the atomic hydrogen (HI) with which they are associated. High-resolution VLA observations are used to measure the properties of HI in the…

We survey the kinematics of over one hundred and fifty candidate (and potentially star-forming) dense cores in the Perseus molecular cloud with pointed N2H+(1-0) and simultaneous C18O(2-1) observations. Our detection rate of N2H+ is 62%,…

We present the results of N2H+(1-0) observations of 35 dense molecular cloud cores from the northern and southern hemispheres where massive stars and star clusters are formed. Line emission has been detected in 33 sources, for 28 sources…

Based on high-latitude molecular clouds with highly accurate distance estimates taken from the literature, we have redetermined the parameters of their spatial orientation. This system can be approximated by a 350x235x140 pc ellipsoid…

We use the $\mathit{Gaia}$ DR2 distances of about 700 mid-infrared selected young stellar objects in the benchmark giant molecular cloud Orion A to infer its 3D shape and orientation. We find that Orion A is not the fairly straight…