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High energy gamma-ray astronomy and high energy physics
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| Galaxy structures in the Hercules region
216 redshifts have been obtained in a region of 981 sq deg south of theHercules supercluster. 172 of these redshifts are of galaxies withmpg less than or equal to 15.1, 110 of which had no previousvelocity measurement. 44 new redshifts are of galaxies fainter thanmpg = 15.1. With these new data we have been able to define asample in a vast region (approximately 1700 sq deg) around Herculeslimited to mpg less than or equal to 15.1 with a velocitycompleteness of 81.5%. 189 galaxies have been morphologically classifiedso that all galaxies in the sample with known velocity now also haveknown morphology. The magnitude limited sample, including 556 galaxies,is then used to identify and describe galaxy structures in the region.We find that the overdense volume is small, that its overall appearanceis that of a coral branch floating in a sea of nothing and that earlyand late type galaxies defined different structures.
| Star counts and carbon monoxide observations of Maddalena's cloud
The inner region of Maddalena's cloud, a massive, cold object in theouter Galaxy has been mapped, in both (C-12)O and (C-13)O (J = 1-0)using the FCRAO 14 m telescope. The visual extinction has beendetermined by star counts and is used to investigate the gas and dustproperties of the cloud. The results indicate that the (C-13)O columndensity to visual extinction ratio is similar to that found in localmolecular clouds. This suggests that if the gas to dust ratio is normal,the CO abundance is similar to that of the clouds near the sun. Themasses derived from the LTE and virial analyses differ by a factor offive; the virial analysis gives a mass five times larger than the LTEvalue. The structure and kinematics of the cloud inferred from the COmaps suggest that the inner region of the cloud may be expanding. Thus,both the kinematics of the cloud and the mass discrepancy suggest thatthis object may not be gravitationally bound. If it is assumed that theLTE mass to be correct, the ratio of molecular hydrogen column densityto CO integrated intensity is much lower than that found for most GMCsin the inner Galaxy.
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