Related papers: Subarcsecond Analysis of Infalling-Rotating Envelo…
Subarcsecond-resolution images of the rotational line emissions of CS and c-C$_3$H$_2$ obtained toward the low-mass protostar IRAS 04368$+$2557 in L1527 with the Atacama Large Millimeter/submillimeter Array are investigated to constrain the…
We have resolved for the first time the radial and vertical structure of the almost edge-on envelope/disk system of the low-mass Class 0 protostar L1527. For that, we have used ALMA observations with a spatial resolution of…
We have analyzed the OCS, H$_2$CS, CH$_3$OH, and HCOOCH$_3$ data observed toward the low-mass protostar IRAS 16293--2422 Source B at a sub-arcsecond resolution with ALMA. A clear chemical differentiation is seen in their distributions; OCS…
We have analyzed rotational spectral line emission of OCS, CH3OH, HCOOCH3, and H2CS observed toward the low-mass Class 0 protostellar source IRAS 16293-2422 Source A at a sub-arcsecond resolution (~0".6 x 0".5) with ALMA. Significant…
We made C18O (2-1) and CS (7-6) images of the protostellar envelope around B335 with a high spatial dynamic range from ~10000 to ~400 AU, by combining the Submillimeter Array and single-dish data. The C18O emission shows an extended (~10000…
We report Atacama Large Millimeter/submillimeter Array (ALMA) cycle 0 observations of C$^{18}$O ($J=2-1$), SO ($J_N= 6_5-5_4$) and 1.3mm dust continuum toward L1527 IRS, a class 0 solar-type protostar surrounded by an infalling and rotating…
Sub-arcsecond ($0.^{\prime\prime}5$) images of H$_2$CO and CCH line emission have been obtained in the $0.8$ mm band toward the low-mass protostar IRAS 15398-3359 in the Lupus 1 cloud as one of the Cycle 0 projects of the Atacama Large…
We present a detailed millimeter line study of the circumstellar environment of the low-luminosity Class 0 protostar IRAM 04191+1522 in the Taurus molecular cloud. New line observations demonstrate that the ~14000 AU radius protostellar…
We present results from our SMA observations and data analyses of the SMA archival data of the Class I protostar IRAS 04169+2702. The high-resolution (~0.5") $^{13}$CO (3-2) image cube shows a compact ($r$ ~< 100 au) structure with a…
The Class 0 protostar IRAS 16293$-$2422 Source A is known to be a binary system (A1 and A2) or even a multiple system, which processes a complex outflow structure. We have observed this source in the C$^{34}$S, SO, and OCS lines at 3.1 mm…
We have imaged the circumstellar envelope around the binary protostar L1551 IRS 5 in CS (J=7-6) and 343 GHz continuum emission at ~ 3 arcsec resolution using the Submillimeter Array. The continuum emission shows an elongated structure (~…
A fundamental question about the early evolution of low-mass protostars is when circumstellar disks may form. High angular resolution observations of molecular transitions in the (sub)millimeter wavelength windows make it possible to…
We have observed the CCH (N=3-2, J=7/2-5/2, F=4-3 and 3-2) and SO (6_7-5_6) emission at a 0"2 angular resolution toward the low-mass Class 0 protostellar source IRAS 15398-3359 with ALMA. The CCH emission traces the infalling-rotating…
We performed SMA observations in the C18O (2-1) emission line toward six Class 0 and I protostars, to study rotational motions of their surrounding envelopes and circumstellar material on 100 to 1000 AU scales. C18O (2-1) emission with…
We have observed the three low-mass protostars, IRAS 15398$-$3359, L1527 IRS and TMC-1A, with the ALMA 12-m array, the ACA 7-m array, and the IRAM-30m and APEX telescopes in the C$^{18}$O $J=2$-1 emission. Overall, the C$^{18}$O emission…
We have observed the Class I protostellar source Elias 29 with Atacama Large Millimeter/submillimeter Array (ALMA). We have detected CS, SO, $^{34}$SO, SO$_2$, and SiO line emissions in a compact component concentrated near the protostar…
We have observed the Class I protostar TMC-1A with Atacama Millimeter/submillimeter Array (ALMA) in 12CO and C18O (J=2-1), and 1.3-mm dust continuum emission. Continuum emission with a deconvolved size of 0.50"x0.37", perpendicular to the…
The collapse of the protostellar envelope results in the growth of the protostar and the development of a protoplanetary disk, playing a critical role during the early stages of star formation. Characterizing the gas infall in the envelope…
We examined the gravitational contraction of isothermal molecular cloud cores with slow rotation by means of two-dimensional numerical simulations. Applying a sink-cell method, we followed the evolution of the cloud cores up to the stages…
We have mapped the central region of the HH 111 protostellar system in 1.33 mm continuum, C18O(J=2-1), 13CO (J=2-1), and SO (N_J=5_6-4_5) emission at ~3" resolution with the Submillimeter Array. There are two sources, VLA 1 (=IRAS…