English
Related papers

Related papers: Maser Source Finding Methods in HOPS

200 papers

This paper presents and discusses the results of basic source finding tests in three dimensions (using spectroscopic data cubes) with Duchamp, the standard source finder for the Australian SKA Pathfinder. For this purpose, we generated…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 Tobias Westmeier , Attila Popping , Paolo Serra

We report a multi-epoch, simultaneous 22 GHz H2O and 44 GHz class I CH3OH maser line survey towards 180 intermediate-mass young stellar objects, including 14 Class 0, 19 Class I objects, and 147 Herbig Ae/Be stars. We detected H2O and CH3OH…

Astrophysics of Galaxies · Physics 2015-05-30 Jae-Han Bae , Kee-Tae Kim , So-Young Youn , Won-Ju Kim , Do-Young Byun , Hyunwoo Kang , Chung Sik Oh

Full polarization measurements of 1665 and 1667-MHz OH masers at sites of massive star formation have been made with the Parkes 64-m radio telescope. Here we present the resulting spectra for 104 northerly sources. For more than 20 masers…

Astrophysics of Galaxies · Physics 2014-02-12 J. L. Caswell , J. A. Green , C. J. Phillips

We report on a time-domain search for pulsars in 44 steep spectrum radio sources originally identified from recent imaging surveys. The time-domain search was conducted at 327 MHz using the Ooty radio telescope, and utilized a semi-coherent…

High Energy Astrophysical Phenomena · Physics 2018-09-05 Yogesh Maan , Cees Bassa , Joeri van Leeuwen , M. A. Krishnakumar , Bhal Chandra Joshi

Point Source (PS) detection is an important issue for future Cosmic Microwave Background (CMB) experiments since they are one of the main contaminants to the recovery of CMB signal at small scales. Improving its multifrequency detection…

Instrumentation and Methods for Astrophysics · Physics 2022-02-09 J. M. Casas , J. González-Nuevo , L. Bonavera , D. Herranz , S. L. Suárez Gómez , M. M. Cueli , D. Crespo , J. D. Santos , M. L. Sánchez , F. Sánchez-Lasheras , F. J. de Cos

Water megamasers from circumnuclear disks in galaxy centers provide the most accurate measurements of supermassive black hole masses and uniquely probe the sub-parsec accretion processes. At the same time, these systems offer independent…

Aims. We study the 2D spectral line profile of HARPS (High Accuracy Radial Velocity Planet Searcher), measuring its variation with position across the detector and with changing line intensity. The characterization of the line profile and…

In this work we address the problem of simultaneous multi-frequency detection of extragalactic point sources in maps of the Cosmic Microwave Background. We apply a new linear filtering technique, the so called `matched matrix filters', that…

Astrophysics · Physics 2009-11-13 D. Herranz , M. Lopez-Caniego , J. L. Sanz , J. Gonzalez-Nuevo

Here I will outline successes and challenges for finding spectral line sources in large data cubes that are dominated by noise. This is a 3D challenge as the sources we wish to catalog are spread over several spatial pixels and spectral…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Baerbel S. Koribalski

We carried out observations of the 22 GHz H2O masers in a high-mass protostar S255 NIRS 3 by using VERA. We measured the proper motions of the 22 GHz H2O masers associated with a bipolar outflow. The expansion velocity of the blueshifted…

We present OH maser observations at 1612, 1665, 1667, and 1720 MHz for 86 post-asymptotic giant branch (post-AGB) stars selected from a survey of 1612 MHz maser sources in the Galactic Plane. The observations were taken with the Parkes…

Astrophysics · Physics 2009-11-10 R. M. Deacon , J. M. Chapman , A. J. Green

We present VLBI observations of the H$_2$O maser emission towards a selection of massive young stellar objects (YSOs). In one of these sources, IRAS20126+4104, the measured proper motions confirm that the water masers spots are tracing the…

Astrophysics · Physics 2007-05-23 M. J. Rioja , L. Moscadelli , R. Cesaroni

The Australia Telescope Compact Array (ATCA) and the Mopra facility have been used to search for new southern class I methanol masers at 9.9, 25 (J=5) and 104 GHz, which are thought to trace more energetic conditions in the interface…

The changes in the spectral line profile of the 22GHz H2O maser are calculated as a function of emerging maser flux. We address not only the narrowing and re-broadening of the maser lines, but also the deviations of Gaussian symmetry as a…

Astrophysics · Physics 2009-11-10 W. H. T. Vlemmings , H. J. van Langevelde

We present an interferometric survey of the 44 GHz class I methanol maser transition toward a sample of 69 sources consisting of High Mass Protostellar Object candidates and Ultracompact (UC) H II regions. We found a 38% detection rate (16…

Astrophysics of Galaxies · Physics 2016-02-17 A. I. Gómez-Ruiz , S. E. Kurtz , E. D. Araya , P. Hofner , L. Loinard

We present MERLIN observations of OH, water and methanol masers towards the young high mass stellar object IRAS 20126+4104. Emission from the 1665-MHz OH, 22-GHz H_2O and 6.7-GHz CH_3OH masers is detected and all originates very close to…

Astrophysics of Galaxies · Physics 2011-07-05 K. A. Edris , G. A. Fuller , R. J. Cohen , S. Etoka

The 22.2 GHz water masers are often associated with the 6.7 GHz methanol masers but owing to the different excitation conditions they likely probe independent spatial and kinematic regions around the powering young massive star. We compared…

Astrophysics of Galaxies · Physics 2015-06-04 Anna Bartkiewicz , Marian Szymczak , Huib Jan van Langevelde

The BeSSeL Survey is mapping the spiral structure of the Milky Way by measuring trigonometric parallaxes of hundreds of maser sources associated with high-mass star formation. While parallax techniques for water masers at high frequency (22…

Instrumentation and Methods for Astrophysics · Physics 2017-07-26 M. J. Reid , A. Brunthaler , K. M. Menten , A. Sanna , Y. Xu , J. J. Li , Y. Wu , B. Hu , X. W. Zheng , B. Zhang , K. Immer , K. Rygl , L. Moscadelli , N. Sakai , A. Bartkiewicz , Y. K. Choi

We report the results of a sensitive search for 12.2 GHz methanol maser emission towards a sample of eight high-mass star formation regions in the Large Magellanic Clouds which have been detected in other maser transitions. We detected one…

Astrophysics of Galaxies · Physics 2015-05-14 S. P. Ellingsen , S. L. Breen , J. L. Caswell , L. J. Quinn , G. A. Fuller

Water is the most common triatomic molecule in the universe and the basis of life on Earth. Astrophysical masers have been widely studied in recent years and have been shown to be invaluable probes of the details of the environment in which…

Astrophysics · Physics 2009-11-11 V. Minier , C. Lineweaver