Results 71 to 80 of about 4,855 (170)
The first detection of the 232 GHz vibrationally excited H2O maser in Orion KL with ALMA
, 2012 We investigated the ALMA science verification data of Orion KL and found a spectral signature of the vibrationally excited H2O maser line at 232.68670 GHz (nu2=1, 5,5,0-6,4,3).
Beuther +10 more
core +1 more source
First Detection of Circular Polarization in 4.7 GHz Excited OH Masers
The Astrophysical JournalWe report the first detection of circular polarization in 4.7 GHz excited OH masers in star-forming regions made using full Stokes measurements with the Green Bank 100 m telescope.
Derck P. Smits, Paul Fallon
doaj +1 more source
Maser Activity of Organic Molecules toward Sgr B2(N)
The Astrophysical JournalAt centimeter wavelengths, single-dish observations have suggested that the Sagittarius (Sgr) B2 molecular cloud at the Galactic Center hosts weak maser emission from several organic molecules, including CH _2 NH, HNCNH, and HCOOCH _3 . However, the lack
Ci Xue +7 more
doaj +1 more source
Detections of Compact Radio Continuum toward Methanol Maser Rings Using the VLA
The Astrophysical JournalHigh-mass protostars are deeply embedded in dust inside their natal cores and are not easily detectable. However, maser emission at centimeter wavelengths, owing to its high brightness, enables us to study gas kinematics in protostars’ circumstellar ...
Anna Bartkiewicz +7 more
doaj +1 more source
Strong magnetic field in W75N OH maser flare
, 2006 A flare of OH maser emission was discovered in W75N in 2000. Its location was determined with the VLBA to be within 110 au from one of the ultracompact H II regions, VLA2. The flare consisted of several maser spots.
Migenes, V., Slysh, V. I.
core +1 more source
On the Structure of the Sagittarius Spiral Arm in the Inner Milky Way
The Astronomical JournalWe report measurements of trigonometric parallax and proper motion for two 6.7 GHz methanol and two 22 GHz water masers located in the far portion of the Sagittarius spiral arm as part of the BeSSeL Survey.
S. B. Bian +8 more
doaj +1 more source
Distribution Properties of the 6.7 GHz Methanol Masers and Their Surrounding Gases in the Milky Way
The Astrophysical JournalAn updated catalog consisting of 1092 6.7 GHz methanol maser sources is reported in this work. Additionally, the NH _3 (1, 1), NH _3 (2, 2), and NH _3 (3, 3) transitions were observed toward 214 star-forming regions using the Shanghai Tianma radio ...
Tian Yang +6 more
doaj +1 more source
The Stellar Content of Obscured Galactic Giant HII Regions. VI: W51A
, 2008 We present K-band spectra of newly born OB stars in the obscured Galactic giant H II region W51A and ~ 0.8'' angular resolution images in the J, H and K_S-bands. Four objects have been spectroscopically classified as O-type stars.
Barbosa, C. L. +4 more
core +1 more source
INTERSTELLAR H2O MASERS FROM J SHOCKS
The Astrophysical Journal, 2013 We present a model in which the 22 GHz H$_2$O masers observed in star-forming regions occur behind shocks propagating in dense regions (preshock density $n_0 \sim 10^6 - 10^8$ cm$^{-3}$). We focus on high-velocity ($v_s > 30$ km s$^{-1}$) dissociative J shocks in which the heat of H$_2$ re-formation maintains a large column of $\sim 300-400$ K gas ...
Hollenbach, David +2 more
openaire +3 more sources
The Astronomical JournalFrom 2019 January to June, the high-mass young stellar object G358.93-0.03 underwent a remarkable accretion burst. Detecting variations in the physical and kinematic environments during episodic accretion is essential for exploring such events. Searching
Shi-jie Zhang +5 more
doaj +1 more source