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We have observed both Comets Hyakutake and Hale–Bopp close to perigee with several telescopes at frequencies between 30 and 860 GHz for an extended period of time. The observed " light " curves can be described as a simple function of heliocentric and geocentric distances without any outburst or noticeable variability with time. Our most sensitive diameter(More)
The first definite discoveries of extragalactic deuterium are reported. DCO + has been detected in three and DCN has been measured in one star-forming region of the Large Magellanic Cloud (LMC). While the HCO + /DCO + abundance ratios are found to be 19 ± 3, 24 ± 4, and 67 ± 18 for N113, N44BC and N159HW, respectively , a HCN/DCN abundance ratio of 23 ± 5(More)
Although changes in magnitude of single traits responding to selective agents have been studied intensively, little is known about selection shaping networks of traits and their patterns of covariation. However, this is central for our understanding of phenotypic evolution as traits are embedded in a multivariate environment with selection affecting a(More)
The large scale structure and physics of molecular gas in the Galactic center region is discussed based on the detailed analysis of a 9 ′ resolution survey of the Galactic center region in the J = 1 → 0 line of C 18 O. Emphasis is placed on the comparison with 12 CO(1–0) data. The line shapes of C 18 O(1–0) and 12 CO(1–0) differ significantly. The ratio of(More)
The large scale structure and physics of molecular gas in the Galactic center region is discussed based on the detailed analysis of a 9 resolution survey of the Galactic center region in the J = 1 → 0 line of C 18 O. Emphasis is placed on the comparison with 12 CO(1–0) data. The line shapes of C 18 O(1–0) and 12 CO(1–0) differ significantly. The ratio of(More)
version lines of ammonia (NH 3) have been detected toward the nuclear 40 00 sized bar of the nearby spiral galaxy Maaei 2. The relative intensities of the ammonia lines are characterized by a rotational temperature of 85 K. This is higher than rotational temperatures measured toward IC 342 and most Galactic Center clouds, implying kinetic temperatures > 100(More)
  • S H Uttemeister, G Dahmen, +4 authors Raiub
  • 2007
Multiline observations of C 18 O and SiO iso-topomers toward 33 molecular peaks in the Galactic center region, taken at the SEST, JCMT and HHT telescopes, are presented. The C 18 O presumably traces the total H 2 column density, while the SiO traces gas aaected by shocks and high temperature chemistry. The J = 2 ! 1 line of SiO is seen only in few regions(More)
version lines of ammonia (NH 3) have been detected toward the nuclear 40 ′′ sized bar of the nearby spiral galaxy Maffei 2. The relative intensities of the ammonia lines are characterized by a rotational temperature of 85 K. This is higher than rotational temperatures measured toward IC 342 and most Galactic Center clouds, implying kinetic temperatures > ∼(More)
Multiline observations of C 18 O and SiO iso-topomers toward 33 molecular peaks in the Galactic center region, taken at the SEST, JCMT and HHT telescopes, are presented. The C 18 O presumably traces the total H 2 column density, while the SiO traces gas affected by shocks and high temperature chemistry. The J = 2 → 1 line of SiO is seen only in few regions(More)
Detections of extragalactic 15 N are reported from observations of the rare hydrogen cyanide isotope HC 15 N toward the Large Magellanic Cloud (LMC) and the core of the (post-) starburst galaxy NGC 4945. Accounting for optical depth effects, the LMC data from the massive star-forming region N113 infer a 14 N/ 15 N ratio of 111 ± 17, about twice the 12 C/ 13(More)