Articles de revues : « Maseru »

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S. P. Tenhoff. « Maseru Casaba 9 ». Antioch Review 71, n^o 2 (2013) : 332. http://dx.doi.org/10.7723/antiochreview.71.2.0332.

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Savenije, H. « The Maseru Conference ». Water Policy 2, n^o 1-2 (1 juin 2000) : 1–7. http://dx.doi.org/10.1016/s1366-7017(99)00020-3.

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Cobbe, James, et David Ambrose. « Maseru : An Illustrated History ». International Journal of African Historical Studies 28, n^o 2 (1995) : 466. http://dx.doi.org/10.2307/221669.

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Epprecht, Marc, David Ambrose et Elizabeth A. Eldredge. « Maseru : An Illustrated History ». Canadian Journal of African Studies / Revue Canadienne des Études Africaines 28, n^o 3 (1994) : 523. http://dx.doi.org/10.2307/485345.

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Epprecht, Marc, David Ambrose et Elizabeth A. Eldredge. « Maseru : An Illustrated History ». African Studies Review 37, n^o 3 (décembre 1994) : 166. http://dx.doi.org/10.2307/524932.

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Romaya, Sam, et Alison Brown. « City profile : Maseru, Lesotho ». Cities 16, n^o 2 (avril 1999) : 123–33. http://dx.doi.org/10.1016/s0264-2751(98)00046-8.

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WRIGHT, CAROLINE. « Maseru : An illustrated history ». African Affairs 93, n^o 373 (octobre 1994) : 620–21. http://dx.doi.org/10.1093/oxfordjournals.afraf.a098768.

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Motsâ€™oene, Keneuoe Anacletta. « Analyzing Gender Disparities in the Labour Market in an Urbanizing City- Maseru, Lesotho ». Journal of Social and Development Sciences 8, n^o 1 (24 avril 2017) : 20–27. http://dx.doi.org/10.22610/jsds.v8i1.1614.

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The study aimed at investigating the gender differences in the labour market of the urban formal sector in Maseru. The research was undertaken to illustrate the existing gender gap between men and women both in occupation and remuneration thus exposing inequality manifestations particularly in an urbanizing city, Maseru. The assessment was carried out in Maseru urban formal sector in three government entities: the National Manpower Development Secretariat, Office of the Auditor General and Ministry of Labour. The three government entities were purposively selected because of easy access of documented data and availability of resource persons to assist during data collection exercise. While at the same time a few interviews were conducted with men working in the taxi industry and the informal sector. Observations as well formed part of approach to the study to ascertain the validity of information obtained from the documented data and interviews. The main finding of the paper is that women in Lesotho the paper concludes that the formal labour market in Maseru is characterized by gender gaps where women occupy well salaried positions as opposed to their male counterparts with these low income jobs thus making men live in vicious cycle of poverty.

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Motsâ€™oene, Keneuoe Anacletta. « Is Womenâ€™s Increased Accessibility to Land a Path to Sustainable Development ? The Case of Urban Maseru, Lesotho ». Journal of Social and Development Sciences 5, n^o 4 (30 décembre 2014) : 176–81. http://dx.doi.org/10.22610/jsds.v5i4.818.

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This study argues that unlike other parts of Africa where women are marginalized and excluded from accessing resources particularly land, women in Lesotho have been empowered through the Act that gives them access to land which had not been the case in the in the past decades. This has made women potential agents in driving the process of sustainable development in the urban echelon of Maseru. The specific objective of this study therefore is to show that women in Lesotho are important catalysts in the sustainable development of Maseru, the capital city of Lesotho. This has increased their ability not only to use land for settlement but also engaged in economic activities that contribute to Lesothoâ€™s sustainable development. The study focused on three urban communities (Ha Foso, Sekamaneng, and Ha Matala) in Maseru. Purposeful sampling was engaged in selecting 80 female-headed households. It was discovered that women had both ownership and user rights of the land they occupied in their own capacity as household heads. The study has six sections: introduction, study objective, rationale, methodology, conceptual framework, study findings, conclusion.

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Senekane, Mpinane Flory, Agnes Makhene et Suzan Oelofse. « Methodology to Investigate Indigenous Solid Waste Systems and Practices in the Rural Areas Surrounding Maseru (Kingdom of Lesotho) ». International Journal of Environmental Research and Public Health 18, n^o 10 (18 mai 2021) : 5355. http://dx.doi.org/10.3390/ijerph18105355.

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Solid waste management (SWM) is the greatest challenge facing environmental protection and human wellbeing in the rural communities of Maseru (Kingsom of Lesotho). A lack of formal waste management (WM) systems in rural areas of Maseru have resulted in different indigenous systems and practices of SWM. Direct observation and descriptive designs will be employed. This is a mixed methods study of qualitative, quantitative and, non-experimental. We obtained data sets from existing official census and statistics of Maseru. We sampled 693 participants from total population of 6917. We received ethical clearance from Research Ethics committee of Health Sciences at the University of Johannesburg, we recruited six field workers. We have preventive equipment (sanitizers, masks, and sterile latex gloves) for COVID-19 infections in place; we have specific design on caps, masks and bags that will identify field workers as they collect data. We will train field workers, administer questionnaires, interview, and observe participants. STATKON will analyse data. The research will share the results with the Ministry of Environment and the community in Lesotho. The results will also be used to educate the rural communities on improved WM. Where weaknesses are identified, mitigation measures can be evaluated and implemented to rectify the negative aspects and improve the systems and practices. The rural communities face challenges such as waste collection services and sanitation facilities and this fact points out that there is a gap in SWM, which favours the existence of indigenous systems and practice of SWM.

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Setšabi, Setšabi, et Resetselemang Clement Leduka. « The Politics of Street Trading in Maseru, Lesotho ». Urban Forum 19, n^o 3 (22 mai 2008) : 221–41. http://dx.doi.org/10.1007/s12132-008-9033-x.

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Crush, Jonathan, Bruce Frayne et Cameron McCordic. « Urban Agriculture and Urban Food Insecurity in Maseru, Lesotho ». Journal of Food Security 5, n^o 2 (26 août 2017) : 33–42. http://dx.doi.org/10.12691/jfs-5-2-3.

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Engels, Dieter, et Felix Bunzel. « A database of circumstellar OH masers ». Proceedings of the International Astronomical Union 3, S242 (mars 2007) : 316–17. http://dx.doi.org/10.1017/s1743921307013208.

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AbstractWe present a new database of circumstellar OH masers at 1612, 1665, and 1667 MHz. The database contains 10774 observations and 2274 stars with OH maser emission detected. The database contains flux densities and velocities of the two strongest maser peaks, the expansion velocity of the shell and the radial velocity of the star. Access to the database is possible over the Web (www.hs.uni-hamburg.de/maserdb), allowing cone searches for individual objects and lists of objects. Object selection is possible on the base of flux densities and velocities.

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MASTER, S. « Henry Edward Richard Bright : a forgotten pioneer of the geological and palaeontological exploration of Lesotho in the 1870s ». Archives of Natural History 35, n^o 2 (octobre 2008) : 191–202. http://dx.doi.org/10.3366/e0260954108000338.

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All existing accounts of the geology of Lesotho (formerly Basutoland), in southern Africa, refer to the pioneering efforts of the Revd S. S. Dornan, published between 1905 and 1908, as the first geological works in this country. However, one Henry Edward Richard Bright had already published two papers on Basutoland geology in the Cape monthly magazine, in 1873 and 1874. The first paper dealt with an uneconomic twelve-inch coal seam south of Maseru. It was accompanied by a sketch map and the first published geological cross-section through any part of Lesotho. In the second paper, dealing with the geology of Basutoland, Bright described the sedimentary strata and first fossil plants from western Basutoland, in rocks today assigned to the upper Karoo Supergroup. Bright erroneously assumed that the whole country was made up of these strata – being unaware of the existence of thick basaltic lava flows that occupied the mountainous high ground. He also recorded the oldest known earthquake from Lesotho (near Maseru, February 1873). Among his mineralogical finds was ilmenite, which we now know as occurring in kimberlitic intrusions. For his various discoveries, Bright deserves to be recognized as a pioneer in the geological and palaeontological exploration of Lesotho.

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Lepheana, Relebohile Juliet, James Wabwire Oguttu et Daniel Nenene Qekwana. « Spatial Patterns of Anthrax Outbreaks and Cases among Livestock in Lesotho, 2005–2016 ». International Journal of Environmental Research and Public Health 17, n^o 20 (19 octobre 2020) : 7584. http://dx.doi.org/10.3390/ijerph17207584.

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Background: Although anthrax occurs globally, the burden of the disease remains particularly high in Africa. Furthermore, the disease anthrax has significant public health and economic implications. However, sufficient attention has not been given to the geographic distribution of anthrax outbreaks and cases in Lesotho. Therefore, this study investigates the spatial patterns of anthrax outbreaks and cases among livestock in Lesotho from 2005 to 2016. Methods: A cross-sectional study design was adopted to realise the objectives of this study using retrospective data of anthrax outbreaks and cases recorded by the Department of Livestock Services (DLS) between 2005 and 2016. Anthrax outbreaks were geo-coded at village level and aggregated at district level. Proportions and 95% CI of anthrax outbreaks and cases by village and district were calculated. Cartographic maps displaying the distribution of anthrax outbreaks and cases at village and district level were constructed. Results: A total of 38 outbreaks were reported over the study period, and they were clustered in the Lowlands districts of Lesotho. Most outbreaks (52.6%, 20/38) in livestock were reported in the Maseru district. The Leribe district reported the lowest proportions of outbreaks (5.3%, 2/38) and cases (0.6%, 3/526). At the village level, 18% (7/38) of outbreaks were in Maseru Urban, followed by Ratau (16%, 6/38) and Mofoka (13%, 5/38). The Maseru district reported the highest (1.3%, 369/29,070) proportion of cases followed by Mafeteng (0.9%, 73/8530). The village with the most cases was Kolo (10.5%, 21/200), followed by Thaba-Chitja (7.7%, 33/430). Conclusion: Anthrax outbreaks and cases exclusively occur in the Lowlands districts of Lesotho, with villages such as Mahobong, Pitseng, Kolo, and Thaba-Chitja having a higher risk of anthrax disease. Findings of the present study have serious public health implications in light of the fact that between 2003 and 2008 Lesotho’s main abattoir was closed; hence, most of the meat in Lesotho was imported and/or sourced from the informal slaughter facilities. Much larger studies are needed to further investigate factors contributing to spatial disparities in anthrax outbreaks and cases observed in this study. Findings of the present study can be used to guide the formulation of a policy on prevention and control of anthrax in Lesotho.

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Ntuli, Victor, Peter Chatanga, Raphael Kwiri, Henry Tendekayi Gadaga, Jephris Gere, Taole Matsepo et Rethabile Portia Potloane. « Microbiological quality of selected dried fruits and vegetables in Maseru, Lesotho ». African Journal of Microbiology Research 11, n^o 5 (7 février 2017) : 185–93. http://dx.doi.org/10.5897/ajmr2016.8130.

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Sjouwerman, Loránt O., et Ylva M. Pihlström. « Class I Methanol Masers in the Galactic Center ». Proceedings of the International Astronomical Union 8, S287 (janvier 2012) : 449–54. http://dx.doi.org/10.1017/s1743921312007508.

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AbstractWe report on 36 and 44 GHz Class I methanol (CH3OH) maser emission in the Sagittarius A (Sgr A) region with the Expanded Very Large Array (EVLA). At least three different maser transitions tracing shocked regions in the cm-wave radio regime can be found in Sgr A. 44 GHz masers correlate with the positions and velocities of 36 GHz CH3OH masers, but the methanol masers correlate less with 1720 MHz OH masers. Our results agree with theoretical predictions that the densities and temperatures conducive for 1720 MHz OH masers may also produce 36 and 44 GHz CH3OH maser emission. However, many 44 GHz masers do not overlap with 36 GHz methanol masers, suggesting that 44 GHz masers also arise in regions too hot and too dense for 36 GHz masers to form. This agrees with the non-detection of 1720 MHz OH masers in the same area, which are thought to be excited under cooler or denser conditions. We speculate that the geometry of the bright 36 GHz masers in Sgr A East outlines the location of a SNR shock front.

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Lankhaar, Boy, et Wouter Vlemmings. « Characterizing maser polarization : effects of saturation, anisotropic pumping, and hyperfine structure ». Astronomy & ; Astrophysics 628 (26 juillet 2019) : A14. http://dx.doi.org/10.1051/0004-6361/201935064.

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Context. The polarization of masers contains information on the magnetic field strength and direction of the regions they occur in. Many maser polarization observations have been performed over the last 30 years. However, versatile maser polarization models that can aide in the interpretation of these observations are not available. Aims. We developed a program suite that can compute the polarization by a magnetic field of any non-paramagnetic maser species at arbitrarily high maser saturation. Furthermore, we investigated the polarization of masers by non-Zeeman polarizing effects. We present a general interpretive structure for maser polarization observations. Methods. We expanded existing maser polarization theories of non-paramagnetic molecules and incorporated them in a numerical modeling program suite. Results. We present a modeling program called CHAracterizes Maser Polarization (CHAMP) that can examine the polarization of masers of arbitrarily high maser saturation and high angular momentum. Hyperfine multiplicity of the maser-transition can also be incorporated. The user is able to investigate non-Zeeman polarizing mechanisms such as anisotropic pumping and polarized incident seed radiation. We present an analysis of the polarization of v = 1 SiO masers and the 22 GHz water maser. We comment on the underlying polarization mechanisms, and also investigate non-Zeeman effects. Conclusions. We identify the regimes where different polarizing mechanisms will be dominant and present the polarization characteristics of the SiO and water masers. From the results of our calculations, we identify markers to recognize alternative polarization mechanisms. We show that comparing randomly generated linear versus circular polarization (pL − pV) scatter-plots at fixed magnetic field strength to the observationally obtained pL − pV scatter can be a promising method of ascertaining the average magnetic field strength of a large number of masers.

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Richter, L. L., A. J. Kemball et J. L. Jonas. « Observational tests of SiO maser polarisation models ». Proceedings of the International Astronomical Union 8, S287 (janvier 2012) : 81–82. http://dx.doi.org/10.1017/s1743921312006692.

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AbstractSiO masers are often observed in the near-circumstellar envelope of late-type evolved stars. The polarisation of the masers can be used as a probe of the magnetic field in this region, subject to maser polarisation radiative transfer model. Two main maser polarisation models have been developed for the weak Zeeman splitting case applicable to circumstellar SiO masers. Observational tests aimed at discriminating between these models were performed at maser component level, using VLBA observations of v=1 J=1-0, v=2 J=1-0 and v=1 J=2-1 SiO masers towards the high-luminosity source VY CMa.

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Richards, A. M. S., I. Bains, A. Bartkiewicz, R. J. Cohen, P. J. Diamond, S. Etoka, M. D. Gray et al. « Turbulent, steamy red supergiant winds ». Proceedings of the International Astronomical Union 3, S242 (mars 2007) : 261–65. http://dx.doi.org/10.1017/s1743921307013105.

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AbstractRapidly-evolving red supergiants (RSG) lose half or more of their mass before ending their lives as supernovae. Masers allow us to study the mass loss from 4 nearby RSG in AU-scale detail using MERLIN and EVN/global VLBI. The water maser clouds are over-dense and over-magnetised with respect to the surrounding wind. In most cases, the brighter an individual maser component is the smaller its apparent (beamed) FWHM appears, as predicted for approximately spherical clouds. Individual water maser features have a typical half-life of 5-10 yr, but comparison with single dish monitoring suggests that the water vapour clouds themselves survive many decades (the water maser shell crossing time), within which the local masers wink on and off. OH mainline masers are found in the tenuous surrounding gas, overlapping the water maser shell, surrounded by OH 1612-MHz masers at a greater distance from the star.

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Maja, Lineo, Thabiso Masia, Kabelo Binyane et Maseabata Ramathebane. « ASSESSMENT OF PATIENT COUNSELLING IN DIABETIC AND HYPERTENSIVE PATIENTS IN TERMS OF PATIENT KNOWLEDGE ABOUT THEIR MEDICATION, DISEASE STATE AND LIFESTYLE MODIFICATIONS BY PHARMACY PERSONNEL AT LDF CLINIC IN MASERU ». International Journal of Pharmacy and Pharmaceutical Sciences 10, n^o 3 (1 mars 2018) : 155. http://dx.doi.org/10.22159/ijpps.2018v10i3.24291.

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Objective: To investigate if diabetic and hypertensive patients were being adequately counselled by pharmacy personnel about their medication, disease states and lifestyle modifications at Lesotho defence force (LDF) clinic in Maseru.Methods: A cross-sectional study was conducted among diabetic and hypertensive patients treated at LDF clinic in Maseru from March to May 2017. A semi-structured questionnaire was used to collect data in a face-to-face interview with patients. Microsoft Excel 2010 was used to analyse collected data.Results: The study population consisted of 222 participants; 22 (28.2%) of diabetic. respondents had inadequate knowledge of diabetes mellitus complications and 56 (71.8%) had no knowledge of complications. 153 (78.8%) of hypertensive respondents had inadequate knowledge of hypertension complications and 33 (17.1%) had no knowledge of complications. 56 (25.2%) had adequate knowledge of lifestyle modifications of diabetes mellitus and hypertension and 164 (73.9%) had inadequate knowledge. 182 (82.0%) had adequate knowledge of their anti-hypertensive and anti-diabetic medicines names, 20 (9.0%) had inadequate knowledge and 20 (9.0%) had no knowledge. 63 (28.4%) had adequate knowledge of their medicines strengths, 17 (7.7%) had inadequate knowledge and 142 (64.0%) had no knowledge. 199 (89.6%) respondents had adequate knowledge of dosing frequency and 20 (9.0%) had inadequate knowledge.Conclusion: Hypertensive and diabetic patients’ knowledge about medication, disease states and lifestyle modifications were inadequate due to poor patient counselling on such aspects by pharmacy personnel at LDF clinic in Maseru.

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Kalenskii, S. V., V. I. Slysh, L. E. B. Johansson, P. Bergman, S. Kurtz, P. Hofner et C. M. Walmsley. « Class I methanol masers in low-mass star formation regions ». Proceedings of the International Astronomical Union 8, S287 (janvier 2012) : 161–65. http://dx.doi.org/10.1017/s1743921312006849.

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AbstractFour Class I maser sources were detected at 44, 84, and 95 GHz toward chemically rich outflows in the regions of low-mass star formation NGC 1333I4A, NGC 1333I2A, HH25, and L1157. One more maser was found at 36 GHz toward a similar outflow, NGC 2023. Flux densities of the newly detected masers are no more than 18 Jy, being much lower than those of strong masers in regions of high-mass star formation. The brightness temperatures of the strongest peaks in NGC 1333I4A, HH25, and L1157 at 44 GHz are higher than 2000 K, whereas that of the peak in NGC 1333I2A is only 176 K. However, a rotational diagram analysis showed that the latter source is also a maser. The main properties of the newly detected masers are similar to those of Class I methanol masers in regions of massive star formation. The former masers are likely to be an extension of the latter maser population toward low luminosities of both the masers and the corresponding YSOs.

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Voronkov, M. A., J. L. Caswell, S. P. Ellingsen, S. L. Breen, T. R. Britton, J. A. Green, A. M. Sobolev et A. J. Walsh. « New class I methanol masers ». Proceedings of the International Astronomical Union 8, S287 (janvier 2012) : 433–40. http://dx.doi.org/10.1017/s174392131200748x.

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AbstractWe review properties of all known collisionally pumped (class I) methanol maser series based on observations with the Australia Telescope Compact Array (ATCA) and the Mopra radio telescope. Masers at 36, 84, 44 and 95 GHz are most widespread, while 9.9, 25, 23.4 and 104 GHz masers are much rarer, tracing the most energetic shocks. A survey of many southern masers at 36 and 44 GHz suggests that these two transitions are highly complementary. The 23.4 GHz maser is a new type of rare class I methanol maser, detected only in two high-mass star-forming regions, G357.97-0.16 and G343.12-0.06, and showing a behaviour similar to 9.9, 25 and 104 GHz masers. Interferometric positions suggest that shocks responsible for class I masers could arise from a range of phenomena, not merely an outflow scenario. For example, some masers might be caused by interaction of an expanding Hii region with its surrounding molecular cloud. This has implications for evolutionary sequences incorporating class I methanol masers if they appear more than once during the evolution of the star-forming region. We also make predictions for candidate maser transitions in the ALMA frequency range.

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Engels, Dieter. « The Hamburg Database of Circumstellar OH Masers ». Proceedings of the International Astronomical Union 8, S287 (janvier 2012) : 256–57. http://dx.doi.org/10.1017/s1743921312007089.

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AbstractA new version of the Hamburg Database of Circumstellar OH Masers at 1612, 1665, and 1667 MHz was released in 2012 January. The database now lists 13170 OH maser observations of stars in the Milky Way. They belong to 6318 different objects and 2324 of them were detected in at least one of the transitions. The database contains flux densities and velocities of the two strongest maser peaks, the expansion velocity of the shell and the radial velocity of the star. Compared to the first version presented in 2007 at the IAU Symposium 242 in Alice Springs new observations published 2008–2011 are included. Interferometric observations and monitoring programs of the maser emission were also added. Access to the database is possible over the Web (www.hs.uni-hamburg.de/maserdb), allowing cone searches for individual objects and lists of objects. A general object search is possible in selected regions of the sky and by defining ranges of flux densities and/or velocities.

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Patel, Nimesh A., Salvador Curiel, Qizhou Zhang, T. K. Sridharan, Paul T. P. Ho et José M. Torrelles. « Submillimeter Array observations of 321 GHz water maser emission in Cepheus A ». Proceedings of the International Astronomical Union 3, S242 (mars 2007) : 489–93. http://dx.doi.org/10.1017/s1743921307013646.

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AbstractUsing the Submillimeter Array (SMA) we have imaged for the first time the 321.226 GHz, 1029 − 936 ortho-H2O maser emission. This is also the first detection of this line in the Cepheus A high-mass star-forming region. The 22.235 GHz, 616 – 523 water masers were also observed with the Very Large Array 43 days following the SMA observations. Three of the nine detected submillimeter maser spots are associated with the centimeter masers spatially as well as kinematically, while there are 36 22 GHz maser spots without corresponding submillimeter masers. In the HW2 source, both the 321 GHz and 22 GHz masers occur within the region of ~1″ which includes the disk-jet system, but the position angles of the roughly linear structures traced by the masers indicate that the 321 GHz masers are along the jet while the 22 GHz masers are perpendicular to it. We interpret the submillimeter masers in Cepheus A to be tracing significantly hotter regions (600~2000 K) than the centimeter masers.

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Breen, S. L., et S. P. Ellingsen. « An evolutionary sequence for high-mass star formation ». Proceedings of the International Astronomical Union 8, S292 (août 2012) : 39. http://dx.doi.org/10.1017/s1743921313000203.

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AbstractDetermining an evolutionary clock for high-mass star formation is an important step towards realizing a unified theory of star formation, as it will enable qualitative studies of the associated high-mass stars to be executed. Our recent studies have shown that masers have great potential to accurately trace the evolution of these regions. We have investigated the relative evolutionary phases associated with the presence of combinations of water, methanol and hydroxyl masers. Comparison between the characteristics of coincident sources has revealed strong evidence for an evolutionary sequence for the different maser species, a result that we now aim to corroborate through comparisons with chemical clocks.Using our new, large samples of methanol masers at 6.7 GHz (MMB survey; Green et al. (2009)) and 12.2 GHz (Breen et al. 2012), 22 GHz water masers (Breen & Ellingsen 2012), OH masers together with complementary data, we find strong evidence that it is not only the presence or absence of the different maser species that indicates the evolutionary stage of the associated high-mass star formation region (see e.g. Breen et al. (2010)), but that the properties of those masers can give even finer evolutionary details. Most notably, the intensity and velocity range of detected maser emission increases as the star forming region evolves (Breen et al. 2011).Subsequent work we have undertaken (Ellingsen et al. 2011) has shown that the presence of rare 37.7 GHz methanol masers may signal the end of the methanol maser phase. They show that 37.7 GHz methanol masers are associated only with the most luminous 6.7 and 12.2 GHz methanol masers, which combined with the rarity of these objects is consistent with them being a short lived phase towards the end of the 6.7 GHz methanol maser lifetime.An independent confirmation of our maser evolutionary timeline can be gained through comparisons with chemical clocks. MALT90 is a legacy survey of 1000s of dense star forming cores at 90GHz, simultaneously observing 16 molecular lines with the Mopra radio telescope (see e.g. Foster et al. 2011). It provides the perfect dataset to test the maser evolutionary timeline due to the targeted lines and the fact that at least one-quarter of the MALT90 sources correspond to maser sites, providing a large enough sample for meaningful analysis. From our preliminary analysis, we find that star formation regions showing similar maser properties also show similar thermal line properties; as would be expected if our evolutionary scenario were accurate.

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Sjouwerman, L. O., et Y. M. Pihlström. « Class I methanol masers in the Galactic center ». Proceedings of the International Astronomical Union 9, S303 (octobre 2013) : 147–49. http://dx.doi.org/10.1017/s1743921314000416.

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AbstractWe report on the detection of 36 and 44 GHz Class I methanol (CH3OH) maser emission in the Sagittarius A (Sgr A) complex with the Karl G. Jansky Very Large Array (VLA). These VLA observations show that the Sgr A complex harbors at least three different maser tracers of shocked regions in the radio regime. The 44 GHz masers correlate with the positions and velocities of previously detected 36 GHz CH3OH masers, but less with 1720 MHz OH masers. Our detections agree with theoretical predictions that the densities and temperatures conducive for 1720 MHz OH masers may also produce 36 and 44 GHz CH3OH maser emission. However, many 44 GHz masers do not overlap with 36 GHz methanol masers, suggesting that 44 GHz masers also arise in regions too hot and too dense for 36 GHz masers to form. This agrees with the non-detection of 1720 MHz OH masers in the same area, which are thought to be excited under even cooler and less dense conditions. We speculate that the geometry of the 36 GHz masers outlines the current location of a shock front.

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Seleteng Kose, Lerato, Annah Moteetee et Sandy Van Vuuren. « Ethnobotanical survey of medicinal plants used in the Maseru district of Lesotho ». Journal of Ethnopharmacology 170 (juillet 2015) : 184–200. http://dx.doi.org/10.1016/j.jep.2015.04.047.

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van der Zaag, P. « Towards improved management of shared river basins : lessons from the Maseru Conference ». Water Policy 2, n^o 1-2 (1 juin 2000) : 47–63. http://dx.doi.org/10.1016/s1366-7017(99)00027-6.

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Rogerson, Christian M., et Tokelo Letsie. « Informal Sector Business Tourism in the Global South : Evidence from Maseru, Lesotho ». Urban Forum 24, n^o 4 (9 avril 2013) : 485–502. http://dx.doi.org/10.1007/s12132-013-9196-y.

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Qiao, Hai-Hua, Andrew J. Walsh, Zhi-Qiang Shen et Joanne R. Dawson. « Ground-state OH maser distributions in the Galactic Centre region ». Proceedings of the International Astronomical Union 11, S322 (juillet 2016) : 141–42. http://dx.doi.org/10.1017/s1743921316011765.

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AbstractGround-state OH masers identified in the Southern Parkes Large-Area Survey in Hydroxyl were observed with the Australia Telescope Compact Array to obtain positions with high accuracy (~1 arcsec). We classified these OH masers into evolved star OH maser sites, star formation OH maser sites, supernova remnant OH maser sites, planetary nebula OH maser sites and unknown maser sites using their accurate positions. Evolved star and star formation OH maser sites in the Galactic Centre region (between Galactic longitudes of −5° to +5° and Galactic latitudes of −2° and +2°) were studied in detail to understand their distributions.

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Yusef-Zadeh, F., D. A. Roberts, Geoff Bower, M. Wardle et W. M. Goss. « Supernova OH (1720 MHz) masers in Sgr A East, W28 and G359.1-0.5 ». Symposium - International Astronomical Union 206 (2002) : 212–16. http://dx.doi.org/10.1017/s0074180900222420.

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A new class of OH (1720 MHz) masers unaccompanied by main-line transitions have recently been discovered (Frail, Goss and Slysh 1994). These masers lie at the interface between supernova remnants (SNRs) interacting with molecular clouds. We discuss three new aspects of SN masers found in the direction toward the Galactic center: (i) the detection of a new −130 kms−1 OH (1720 MHz) maser in the southern lobe of the molecular ring at the Galactic center: (ii) the detection of extended OH (1720 MHz) maser emission from W28 accompanying the compact maser sources and (iii) the detection of linear polarization of the brightest OH (1720 MHz) maser in SNR G359.1-0.5.

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Green, J. A., J. L. Caswell, G. A. Fuller, A. Avison, S. L. Breen, K. Brooks, M. G. Burton et al. « Star-formation masers in the Magellanic Clouds : A multibeam survey with new detections and maser abundance estimates ». Proceedings of the International Astronomical Union 4, S256 (juillet 2008) : 227–32. http://dx.doi.org/10.1017/s1743921308028482.

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AbstractThe results of the first complete survey for 6668-MHz CH3OH and 6035-MHz excited-state OH masers in the Small and Large Magellanic Clouds are presented. A new 6668-MHz CH3OH maser in the Large Magellanic Cloud has been detected towards the star-forming region N 160a, together with a new 6035-MHz excited-state OH maser detected towards N 157a. We also re-observed the previously known 6668-MHz CH3OH masers and the single known 6035-MHz OH maser. Neither maser transition was detected above ~0.13 Jy in the Small Magellanic Cloud. All observations were initially made using the CH3OH Multibeam (MMB) survey receiver on the 64-m Parkes radio telescope as part of the overall MMB project. Accurate positions were measured with the Australia Telescope Compact Array (ATCA). In a comparison of the star formation maser populations in the Magellanic Clouds and our Galaxy, the LMC maser populations are demonstrated to be smaller than their Milky Way counterparts. CH3OH masers are under-abundant by a factor of ~50, whilst OH and H2O masers are a factor of ~10 less abundant than our Galaxy.

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Esimbek, Jarken, Jian Jun Zhou, Gang Wu et Xin Di Tang. « Infrared characteristics of sources associated with OH, H2O, SiO and CH3OH masers ». Proceedings of the International Astronomical Union 8, S287 (janvier 2012) : 178–79. http://dx.doi.org/10.1017/s1743921312006886.

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AbstractWe collect all published OH, H2O, SiO and CH3OH masers in the literature. The associated infrared sources of these four masers were identified with MSX PSC catalogues. We look for common infrared properties among the sources associated with four masers and make a statistical study. The MSX sources associated with stellar OH, stellar H2O and SiO masers concentrated in a small regions and the MSX sources associated with interstellar OH, interstellar H2O and CH3OH masers also concentrated in a small regions in an [A]-[D].vs.[A][-[E] diagram. These results give us new criterion to search for coexisting stellar maser samples for OH, H2O and SiO masers and interstellar maser samples for OH, H2O and CH3OH masers.

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Stecklum, Bringfried, Alessio Caratti o. Garatti, Klaus Hodapp, Hendrik Linz, Luca Moscadelli et Alberto Sanna. « Infrared variability, maser activity, and accretion of massive young stellar objects ». Proceedings of the International Astronomical Union 13, S336 (septembre 2017) : 37–40. http://dx.doi.org/10.1017/s1743921317010511.

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AbstractMethanol and water masers indicate young stellar objects. They often exhibit flares, and a fraction shows periodic activity. Several mechanisms might explain this behavior but the lack of concurrent infrared (IR) data complicates the identification of its cause. Recently, 6.7 GHz methanol maser flares were observed, triggered by accretion bursts of high-mass YSOs which confirmed the IR-pumping of these masers. This suggests that regular IR changes might lead to maser periodicity. Hence, we scrutinized space-based IR imaging of YSOs associated with periodic methanol masers. We succeeded to extract the IR light curve from NEOWISE data for the intermediate mass YSO G107.298+5.639. Thus, for the first time a relationship between the maser and IR variability could be established. While the IR light curve shows the same period of ~34.6 days as the masers, its shape is distinct from that of the maser flares. Possible reasons for the IR periodicity are discussed.

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Billington, S. J., J. S. Urquhart, C. König, H. Beuther, S. L. Breen, K. M. Menten, J. Campbell-White et al. « ATLASGAL – relationship between dense star-forming clumps and interstellar masers ». Monthly Notices of the Royal Astronomical Society 499, n^o 2 (29 septembre 2020) : 2744–59. http://dx.doi.org/10.1093/mnras/staa2936.

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ABSTRACT We have used catalogues from several Galactic plane surveys and dedicated observations to investigate the relationship between various maser species and Galactic star-forming clumps, as identified by the APEX Telescope Large Area Survey of the Galaxy (ATLASGAL) survey. The maser transitions of interest are the 6.7 and 12.2-GHz methanol masers, 22.2-GHz water masers, and the masers emitting in the four ground-state hyperfine structure transitions of hydroxyl. We find clump association rates for the water, hydroxyl and methanol masers to be 56, 39, and 82 per cent, respectively, within the Galactic longitude range of 60○ > ℓ > −60○. We investigate the differences in physical parameters between maser associated clumps and the full ATLASGAL sample, and find that clumps coincident with maser emission are more compact with increased densities and luminosities. However, we find the physical conditions within the clumps are similar for the different maser species. A volume density threshold of n(H2) > 104.1 cm−3 for the 6.7-GHz methanol maser found in our previous study is shown to be consistent across for all maser species investigated. We find limits that are required for the production of maser emission to be 500 L⊙ and 6 M⊙, respectively. The evolutionary phase of maser associated clumps is investigated using the L/M ratio of clumps coincident with maser emission, and these have similar L/M ranges (∼100.2−102.7 L⊙/M⊙) regardless of the associated transitions. This implies that the conditions required for the production of maser emission only occur during a relatively narrow period during a star’s evolution. Lower limits of the statistical lifetimes for each maser species are derived, ranging from ∼0.4−2 × 104 yr and are in good agreement with the ‘straw man’ evolutionary model previously presented.

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Ogbodo, C. S., J. A. Green, J. R. Dawson, S. L. Breen, S. A. Mao, N. M. McClure-Griffiths, T. Robishaw et L. Harvey-Smith. « MAGMO : polarimetry of 1720-MHz OH masers towards southern star-forming regions ». Monthly Notices of the Royal Astronomical Society 493, n^o 1 (20 janvier 2020) : 199–233. http://dx.doi.org/10.1093/mnras/staa167.

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ABSTRACT From targeted observations of ground-state hydroxyl (OH) masers towards 702 Methanol Multibeam survey 6.7-GHz methanol masers, in the Galactic longitude range from 186° through the Galactic Centre to 20°, made as part of the ‘MAGMO’ (Mapping the Galactic Magnetic field through OH masers) project, we present the physical and polarization properties of the 1720-MHz OH maser transition, including the identification of Zeeman pairs. We present 10 new and 23 previously catalogued 1720-MHz OH maser sources detected towards star-forming regions (SFRs). In addition, we also detected 16 1720-MHz OH masers associated with supernova remnants and two sites of diffuse OH emission. Towards the 33 star formation masers, we identify 44 Zeeman pairs, implying magnetic field strengths ranging from −11.4 to +13.2 mG, and a median magnetic field strength of |BLOS| ∼ 6 mG. With limited statistics, we present the in situ magnetic field orientation of the masers and the Galactic magnetic field distribution revealed by the 1720-MHz transition. We also examine the association statistics of 1720-MHz OH SFR masers with other ground-state OH masers, excited-state OH masers, class I and class II methanol masers, and water masers, and compare maser positions with mid-infrared images of the parent SFRs. Of the 33 1720-MHz star formation masers, 10 are offset from their central exciting sources, and appear to be associated with outflow activity.

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Braatz, James. « Testing extragalactic H2O masers against the thin disk model : the present and the future ». Symposium - International Astronomical Union 206 (2002) : 396–99. http://dx.doi.org/10.1017/s0074180900222778.

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Water maser emission is detected towards the nuclei of 22 galaxies, all of them showing some sign of nuclear activity. Except for a couple of cases, maser features have been found only within 150 km s−1 of the systemic galaxy recession velocity but are often offset from systemic within that window. Spectral features in maser-detected galaxies are monitored regularly and these observations show that velocity drifts like those seen in the systemic masers of NGC 4258 are rare. Hence the conclusion that either masers in other galaxies are generally located farther from the central black hole than in NGC 4258, that the black holes in those galaxies are less massive than the one in NGC 4258, or that the masers' acceleration is in the plane of the sky (as in the case of maser gas at the projected extremities of an edge-on disk). Assuming the disk model holds, the last of these options leads to the possibility that, despite the relative faintness of high velocity maser features in the case of NGC 4258, the brightest maser emission originates from the projected edges of the disk, in general. A selection effect would have caused a bias, then, in previous surveys whereby masers in larger, more slowly rotating disks are favorably detected. New wide-bandwidth capabilities at the 100-m Effelsberg telescope and the emergence of the GBT will help to overcome any such bias and provide new examples of maser sources.

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Yang, Haneul, Se-Hyung Cho, Youngjoo Yun, Dong-Hwan Yoon, Dong-Jin Kim, Hyosun Kim, Sung-Chul Yoon, Richard Dodson, María J. Rioja et Hiroshi Imai. « Asymmetric distributions of H2O and SiO masers towards V627 Cas ». Monthly Notices of the Royal Astronomical Society 495, n^o 1 (5 mai 2020) : 1284–90. http://dx.doi.org/10.1093/mnras/staa1206.

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ABSTRACT We performed simultaneous observations of the $\rm H_2O$ 61,6 − 52,3 (22.235080 GHz) and SiO v = 1, 2, J = 1 → 0, SiO v = 1, J = 2 → 1, 3 → 2 (43.122080, 42.820587, 86.243442, and 129.363359 GHz) masers towards the suspected D-type symbiotic star, V627 Cas, using the Korean VLBI Network. Here, we present astrometrically registered maps of the $\rm H_2O$ and SiO v = 1, 2, J = 1 → 0, SiO v = 1, J = 2 → 1 masers for five epochs from January 2016 to June 2018. Distributions of the SiO maser spots do not show clear ring-like structures, and those of the $\rm H_2O$ maser are biased towards the north–north-west to west with respect to the SiO maser features according to observational epochs. These asymmetric distributions of $\rm H_2O$ and SiO masers are discussed based on two scenarios of a bipolar outflow and the presence of the hot companion, a white dwarf, in V627 Cas. We carried out ring fitting of SiO v = 1, and v = 2 masers and estimated the expected position of the cool red giant. The ring radii of the SiO v = 1 maser are slightly larger than those of the SiO v = 2 maser, as previously known. Our assumption for the physical size of the SiO maser ring of V627 Cas to be the typical size of a SiO maser ring radius (∼4 au) of red giants yields the distance of V627 Cas to be ∼1 kpc.

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Sobolev, A. M., D. M. Cragg, S. P. Ellingsen, M. J. Gaylard, S. Goedhart, C. Henkel, M. S. Kirsanova et al. « How do methanol masers manage to appear in the youngest star vicinities and isolated molecular clumps ? » Proceedings of the International Astronomical Union 3, S242 (mars 2007) : 81–88. http://dx.doi.org/10.1017/s1743921307012616.

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AbstractGeneral characteristics of methanol (CH3OH) maser emission are summarized. It is shown that methanol maser sources are concentrated in the spiral arms. Most of the methanol maser sources from the Perseus arm are associated with embedded stellar clusters and a considerable portion is situated close to compact HII regions. Almost 1/3 of the Perseus Arm sources lie at the edges of optically identified HII regions which means that massive star formation in the Perseus Arm is to a great extent triggered by local phenomena. A multiline analysis of the methanol masers allows us to determine the physical parameters in the regions of maser formation. Maser modelling shows that class II methanol masers can be pumped by the radiation of the warm dust as well as by free-free emission of a hypercompact region (hcHII) with a turnover frequency exceeding 100 GHz. Methanol masers of both classes can reside in the vicinity of hcHIIs. Modelling shows that periodic changes of maser fluxes can be reproduced by variations of the dust temperature by a few percent which may be caused by variations in the brightness of the central young stellar object reflecting the character of the accretion process. Sensitive observations have shown that the masers with low flux densities can still have considerable amplification factors. The analysis of class I maser surveys allows us to identify four distinct regimes that differ by the series of their brightest lines.

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Watson, William D. « Theory and extragalactic masers ». Symposium - International Astronomical Union 206 (2002) : 464–78. http://dx.doi.org/10.1017/s0074180900222882.

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Theoretical research on extragalactic masers (and hence this review) is almost entirely directed toward 22 GHz water masers in circumnuclear disks with the focus being the near ideal masing disk at the nucleus of the galaxy NGC4258. The discussion here is organized around (1) the excitation and conditions for the masers, (2) the spatial and spectral appearance of the maser emission, and (3) the mass accretion rate and structure of the disk. In addition, a summary is given of the basic physics (spectral linebreadths and maser polarization) that underlies certain interpretations of these and other astrophysical masers.

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Horiuchi, S., et V. Migenes. « OH and H2O Maser Distribution in Orion KL ». International Astronomical Union Colloquium 164 (1998) : 373–74. http://dx.doi.org/10.1017/s0252921100045991.

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AbstractIn order to study the powering source behind KL nebula, we made a map of OH and H2O masers from VLA observations of this region, and compared their spatial distribution and velocity structure with that of the SiO masers. The distribution of the OH masers consists of a multi-stream structure and seems to be related to the Hot Core molecular emission. The low velocity H2O masers may be classified as two groups: i) an inner clump of maser spots surrounding the SiO maser disc and continuum source “I”, and ii) component associated with the Hot Core represented by HDO emission peaks.

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Harvey-Smith, L., R. Soria-Ruiz, A. Duarte-Cabral et R. J. Cohen. « Discovery of polarized 6.7-GHz methanol masers in DR21/W75 ». Proceedings of the International Astronomical Union 3, S242 (mars 2007) : 154–55. http://dx.doi.org/10.1017/s174392130701277x.

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AbstractWe present the first images of 6.7 GHz methanol masers in the DR21 star-forming complex. We have discovered two sites of Class II methanol maser emission; in DR21(OH) and DR21(OH)N. The emission comprises clusters of linearly extended masers which have velocity gradients along their length. There are four maser spots in DR21(OH)N, some of which show a small fraction of linear polarization. The twelve masers in DR21(OH) lie in a linear arrangement stretching approximately 0.7 arcseconds and show no significant linear polarization. We were not able to detect any circular polarization in the masers.

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Sobolev, Andrej M., Andrei B. Ostrovskii, Alexey V. Malyshev, Dinah M. Cragg, Peter D. Godfrey, Edmund C. Sutton, William D. Watson, Simon P. Ellingsen et Jim L. Caswell. « Models of class II methanol masers ». Symposium - International Astronomical Union 206 (2002) : 179–82. http://dx.doi.org/10.1017/s0074180900222353.

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Current models of class II methanol masers are able to describe the brightnesses of the strongest masers and provide a basis for explaining observed line ratios. Determination of the physical parameters in the source requires observational data in many maser transitions. In order to provide observational constraints for models we searched for and detected 7 new methanol masers. This allowed us to constrain the physical parameters of the 3 sources with the greatest number of detected methanol maser lines: W3(OH), NGC6334F, and G345.01 + 1.79. The models accurately account for the fluxes of the bulk of the detected maser lines. Remaining discrepancies most probably reflect the fact that the most prominent components of the different maser lines are formed under different conditions. This is supported by comparison of the line profiles. We outline directions for future studies in the field.

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Mugomeri, Eltony, Khothatso Seliane, Peter Chatanga et Charles Maibvise. « IDENTIFYING PROMOTERS AND REASONS FOR MEDICINAL HERB USAGE DURING PREGNANCY IN MASERU, LESOTHO ». Africa Journal of Nursing and Midwifery 17, n^o 1 (17 août 2015) : 4–16. http://dx.doi.org/10.25159/2520-5293/63.

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Moscadelli, L., A. Sanna, C. Goddi, V. Krishnan, F. Massi et F. Bacciotti. « Protostellar Outflows at the EarliesT Stages (POETS) ». Astronomy & ; Astrophysics 635 (mars 2020) : A118. http://dx.doi.org/10.1051/0004-6361/202037472.

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Context. 22 GHz water masers are the most intense and widespread masers in star-forming regions. They are commonly associated with protostellar winds and jets emerging from low- and high-mass young stellar objects (YSO). Aims. We wish to perform for the first time a statistical study of the location and motion of individual water maser cloudlets, characterized by typical sizes that are within a few au, with respect to the weak radio thermal emission from YSOs. Methods. For this purpose, we have been carrying out the Protostellar Outflows at the EarliesT Stages survey of a sample (38) of high-mass YSOs. The 22 GHz water maser positions and three-dimensional (3D) velocities were determined through multi-epoch Very Long Baseline Array observations with accuracies of a few milliarcsec (mas) and a few km s−1, respectively. The position of the ionized core of the protostellar wind, marking the YSO, was determined through sensitive radio continuum, multi-frequency Jansky Very Large Array observations with a typical error of ≈20 mas. Results. The statistic of the separation of the water masers from the radio continuum shows that 84% of the masers are found within 1000 au from the YSO and 45% of them are within 200 au. Therefore, we can conclude that the 22 GHz water masers are a reliable proxy for locating the position of the YSO. The distribution of maser luminosity is strongly peaked towards low values, indicating that about half of the maser population is still undetected with the current Very Long Baseline Interferometry detection thresholds of 50–100 mJy beam−1. Next-generation, sensitive (at the nJy level) radio interferometers will have the capability to exploit these weak masers for an improved sampling of the velocity and magnetic fields around the YSOs. The average direction of the water maser proper motions provides a statistically-significant estimate for the orientation of the jet emitted by the YSO: 55% of the maser proper motions are directed on the sky within an angle of 30° from the jet axis. Finally, we show that our measurements of 3D maser velocities statistically support models in which water maser emission arises from planar shocks with propagation direction close to the plane of the sky.

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Bergman, P., et E. M. L. Humphreys. « Submillimetre water masers at 437, 439, 471, and 474 GHz towards evolved stars ». Astronomy & ; Astrophysics 638 (juin 2020) : A19. http://dx.doi.org/10.1051/0004-6361/202037774.

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Aims. Here we aim to characterise submillimetre water masers at 437, 439, 471, and 474 GHz towards a sample of evolved stars. Methods. We used the Atacama Pathfinder Experiment (APEX1) to observe submillimetre water transitions and the CO (4–3) line towards 11 evolved stars. The sample included semi-regular and Mira variables, plus a red supergiant star. We performed radiative transfer modelling for the water masers. We also used the CO observations to determine mass loss rates for the stars. Results. From the sample of 11 evolved stars, 7 display one or more of the masers at 437, 439, 471, and 474 GHz. We therefore find that these masers are common in evolved star circumstellar envelopes. The fact that the maser lines are detected near the stellar velocity indicates that they are likely to originate from the inner circumstellar envelopes of our targets. We tentatively link the presence of masers to the degree of variability of the target star, that is, masers are more likely to be present in Mira variables than in semi-regular variables. We suggest that this indicates the importance of strong shocks in creating the necessary conditions for the masers. Typically, the 437 GHz line is the strongest maser line observed among those studied here. We cannot reproduce the above finding in our radiative transfer models. In general, we find that maser emission is very sensitive to dust temperature in the lines studied here. To produce strong maser emission, the dust temperature must be significantly lower than the gas kinetic temperature. In addition to running grids of models in order to determine the optimum physical conditions for strong masers in these lines, we performed smooth wind modelling for which we cannot reproduce the observed line shapes. This also suggests that the masers must originate predominantly from the inner envelopes.

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Cho, Se-Hyung, Youngjoo Yun, Jaeheon Kim, Dong-Hwan Yoon, Dong-Jin Kim, Yoon Kyung Choi, Richard Dodson, María Rioja et Hiroshi Imai. « A study on evolved stars by simultaneous observations of H2O and SiO masers using KVN ». Proceedings of the International Astronomical Union 13, S336 (septembre 2017) : 359–64. http://dx.doi.org/10.1017/s1743921317010274.

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AbstractThe Korean VLBI Network (KVN) is a unique millimeter VLBI system which is consisted of three 21 m telescopes with relatively short baselines. We present the preliminary results of simultaneous monitoring observations of the 22.2 GHz H2O and 43.1/42.8/86.2/129.3 GHz SiO masers based on the KVN Key Science Project (KSP). We obtained the astrometrically registered maps of the H2O and SiO masers toward nine evolved stars using the source frequency phase referencing method (SFPR). The SFPR maps of the H2O and SiO masers enabled us to investigate the spatial structure and kinematics from the SiO to H2O maser regions including the development of an outward motion from the ring-like or elliptical structures of SiO masers to the asymmetric structures of the 22.2 GHz H2O maser features. In particular, the 86.2/129.3 GHz SiO (v=1, J=2–1 and J=3–2) masers were clearly imaged toward several objects for the first time. The SiO v=1, J=3–2 maser shows different distributions compared to those of the SiO v=1, 2, J=1–0 and v=1, J=2–1 masers implying a different physical condition.

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Kalenskii, S., S. Kurtz, P. Hofner, P. Bergman, C. M. Walmsley et P. Golysheva. « Class I methanol masers in low-mass star formation regions ». Proceedings of the International Astronomical Union 13, S336 (septembre 2017) : 33–36. http://dx.doi.org/10.1017/s1743921317010961.

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AbstractWe present a review of the properties of Class I methanol masers detected in low-mass star forming regions (LMSFRs). These masers, henceforth called LMMIs, are associated with postshock gas in the lobes of chemically active outflows in LMSFRs NGC1333, NGC2023, HH25, and L1157. LMMIs share the main properties with powerful masers in regions of massive star formation and are a low-luminosity edge of the total Class I maser population. However, the exploration of just these objects may push forward the exploration of Class I masers, since many LMSFRs are located only 200–300 pc from the Sun, making it possible to study associated objects in detail. EVLA observations with a 0.2″ spatial resolution show that the maser images consist of unresolved or barely resolved spots with brightness temperatures up to 5 × 105 K. The results are “marginally” consistent with the turbulent model of maser emission.

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Yi, Jiyune, Chris J. Phillips et Roy S. Booth. « Masers in G34.3+0.2 : What more can 6.7-GHz methanol masers tell us ? » Symposium - International Astronomical Union 206 (2002) : 159–62. http://dx.doi.org/10.1017/s0074180900222304.

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We present results of 6.7 GHz methanol maser observations using the European VLBI Network (EVN) toward the G34.3+0.2 complex, which contains a prototypical cometary HII region and a dust enshrouded, probably emerging massive star, G34.24+0.13. We have investigated the methanol maser distribution in both objects and compared it with the OH and water masers in the main HII region. The masers in G34.24+0.13 lie on top of the 1.3 mm continuum emission showing that methanol masers are present, even at this early evolutionary stage.

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