Measurements of kilometer cosmic radioemission in interplanetary space

Kilometer cosmic radioemission measurements in interplanetary space from Zond 2, Zond 3, and Venera 2 probe

Strong magnetic field in W75N OH maser flare

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. Four of the spots were found to form Zeeman pairs, all of them with a magnetic field strength of about 40 mG. This is the highest ever magnetic field strength found in OH masers, an order of magnitude higher than in typical OH masers. Three possible sources for the enhanced magnetic field are discussed: (i) the magnetic field of the exciting star dragged out by the stellar wind; (ii) the general interstellar field in the gas compressed by the MHD shock; and (iii) the magnetic field of planets which orbit the exciting star and produce maser emission in gaseous envelopes.Comment: 5 pages, 3 figures. to be published in MNRA

Detection of new sources of methanol emission at 107 and 108 GHz with the Mopra telescope

A southern hemisphere survey of methanol emission sources in two millimeter wave transitions has been carried out using the ATNF Mopra millimetre telescope. Sixteen emission sources have been detected in the 3(1)-4(0)A+ transition of methanol at 107 GHz, including six new sources exhibiting class II methanol maser emission features. Combining these results with the similar northern hemisphere survey, a total of eleven 107-GHz methanol masers have been detected. A survey of the methanol emission in the 0(0)-1(-1)E transition at 108 GHz resulted in the detection of 16 sources; one of them showing maser characteristics. This is the first methanol maser detected at 108 GHz, presumably of class II. The results of LVG statistical equilibrium calculations confirm the classification of these new sources as a class II methanol masers.Comment: 11 pages, 6 figures, accepted for publication in MNRAS, mn.sty include

First Interstellar HCO+^+ Maser

A previously unseen maser in the J = 1 - 0 transition of HCO$^+$ has been detected by the Combined Array for Millimeter-wave Astronomy (CARMA). A sub-arcsecond map was produced of the 2 arcmin$^2$ region around DR21(OH), which has had previous detections of OH and methanol masers. This new object has remained undetected until now due to its extremely compact size. The object has a brightness temperature of $>$ 2500 K and a FWHM linewidth of 0.497 km s$^{-1}$, both of which suggest non-thermal line emission consistent with an unsaturated maser. This object coincides in position and velocity with the methanol maser named DR21(OH)-1 by \citet{plambeck90}. No compact HCO$^+$ emission was present in the CARMA data towards the other methanol masers described in that paper. These new results support the theory introduced in \citet{plambeck90} that these masers likely arise from strong outflows interacting with low mass, high density pockets of molecular gas. This is further supported by recent observations of a CO outflow by \citet{zapata12} that traces the outflow edges and confirms that the maser position lies along the edge of the outflow where interaction with molecular tracers can occur.Comment: 4 pages, 3 figures, accepted by ApJL on September 10, 201

Preparation, purification and cis-trans isomerization of 2-butene-1, 4-diol

The preparation of cis- and trans-2-butene-1,4-diol has been reported in chemical literature by numerous workers. A well established procedure to obtain the cis isomer is to hydrogenate 2-butyne-1,4-diol at two to four atmospheres pressure in the presence of catalysts, such as Raney nickel or colloidal palladium. This reduction is selective and can be stopped easily at the ethylenic stage. The reaction has been studied by Lozac\u27h who stated that the Raman spectrum of 2-butene-1,4-diol prepared in this way indicates the presence of the cis iomer only. Lozac\u27h does not mention the degree of purity of this product and nothing could be found about purity in other articles dealing with the preparation of cis-2-butene-1,4-diol. It is reasonable to believe that in the preparation of this compound under ordinary laboratory conditions small amounts of 2-butyne- and/or butane-1,4-diol may be present. The boiling points of these two are close to the boiling point of the olefin and it would be very difficult to separate the latter from the other two by distillation